SHEAR BAND CONSTRUCTION

Abstract

A shear band for a tire includes an annular first, radially outer fabric layer extending circumferentially around the tire; and an annular second, radially inner fabric layer extending circumferentially around the tire. The shear band is formed from a single shear band strip helically wound circumferentially and axially with a first edge of the shear band strip. The first edge of the shear band strip has a first extension flap for engaging an opposite second edge of the shear band strip. The first extension flap is continuously secured to the opposite second edge linearly along the opposite second edge of the shear band strip.

Claims

1. A shear band for a tire comprising: an annular first, radially outer fabric layer extending circumferentially around the tire; and an annular second, radially inner fabric layer extending circumferentially around the tire, the shear band being formed from a single shear band strip helically wound circumferentially and axially with a first edge of the shear band strip, the first edge of the shear band strip having a first extension flap for engaging an opposite second edge of the shear band strip, the first extension flap being continuously secured to the opposite second edge linearly along the second opposite edge of the shear band strip.

2. The shear band as set forth in claim 1 wherein a first planar side of the single shear band strip comprises the first, radially outer fabric layer and a second planar side of the single shear band strip comprises the second, radially inner fabric layer.

3. The shear band as set forth in claim 2 wherein a blade cuts the helically wound shear band strip such that the single helically wound shear band strip has annular parallel opposite edges define the first planar side and the second planar side.

4. The shear band as set forth in claim 1 wherein the first extension flap is secured to the opposite second edge by stitch-knitting.

5. The shear band as set forth in claim 1 wherein part of the first radially outer fabric layer of the shear band includes the first extension flap.

6. The shear band as set forth in claim 1 wherein the second edge of the shear band strip has a second extension flap for engaging the opposite first edge of the shear band strip.

7. The shear band as set forth in claim 6 wherein the second edge of the shear band strip has a second extension flap for engaging the opposite first edge of the shear band strip, the second extension flap being continuously secured to the opposite first edge linearly along the second opposite edge of the shear band strip.

8. The shear band as set forth in claim 6 wherein the second extension flap is continuously secured to the opposite first edge linearly along the first opposite edge of the shear band strip.

9. The shear band as set forth in claim 6 wherein the second extension flap is secured to the opposite first edge by stitch-knitting.

10. The shear band as set forth in claim 6 wherein part of the second radially outer fabric layer of the shear band includes the second extension flap.

11. A method for constructing a plurality of shear bands for tires, the method includes the steps of: helically winding a single shear band strip about itself to produce a cylindrical structure; securing a first edge of the single shear band strip to a second opposite edge of the single shear band strip by a first flap extending from the first edge of the single shear band strip; and axially and circumferentially cutting the cylindrical structure in multiple locations.

12. The method as set forth in claim 11 wherein the cutting step produces the plurality of annular shear bands with axially opposite parallel sides.

13. The method as set forth in claim 11 wherein the cutting step produces a first, radially outer fabric layer of each of the plurality of shear bands from a first planar side of the single shear band strip.

14. The method as set forth in claim 13 wherein the cutting step produces a second, radially inner fabric layer of each of the plurality of shear bands from a second planar side of the single shear band strip.

15. The method as set forth in claim 14 further including the step of securing the first flap of the first edge of the single shear band strip to an opposite second edge of the single shear band strip by stitch-knitting.

16. The method as set forth in claim 15 wherein the first radially outer fabric layers of each shear band includes part of the first flap extending from the first edge of the single shear band strip.

17. The method as set forth in claim 16 wherein the second radially inner fabric layers of each shear band includes part of a second flap extending from the second edge of the single shear band strip.

18. The method as set forth in claim 17 further including the step of securing the second flap of the second edge of the single shear band strip to an opposite first edge of the single shear band strip by stitch-knitting.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0110] A full and enabling disclosure of examples of the present invention, directed to one of ordinary skill in the art, is set forth in the specification with reference to the appended figures, in which:

[0111] FIG. 1 is a schematic perspective view of part of an example shear band for use with the present invention.

[0112] FIG. 2 is schematic top view of the part of FIG. 1.

[0113] FIG. 3 is a schematic perspective view of the shear band of FIG. 1.

[0114] FIG. 4 is another schematic perspective view the shear band of FIG. 1.

[0115] FIG. 5 is still another schematic perspective view the shear band of FIG. 1.

[0116] FIG. 6 is a schematic perspective view of the shear band of FIG. 1 spirally wound into a cylinder in accordance with the present invention.

[0117] Similar numerals refer to similar parts throughout the drawings.

DETAILED DESCRIPTION OF EXAMPLES OF THE PRESENT INVENTION

[0118] Reference will now be made in detail to examples of the present invention, one or more examples of which are illustrated in the figures. These examples may be used in tires, such as described in the example tire of U.S. Pat. No. 10,071,603, incorporated herein by reference in its entirety. Each example is provided by way of explanation of the present invention, and not meant as a limitation of the present invention. For example, features illustrated or described as part of one example may be used with another example to yield still a third example. It is intended that the present invention include these and other modifications and variations. It should be noted that for the purposes of discussion, only part of example tires may be depicted in one or more of the figures. One of ordinary skill in the art, using the teachings disclosed herein, will understand that the same or substantially similar features may be repeated in other parts the example tires.

[0119] The present invention provides an improved shear band that may be used in a variety of products including, for example, non-pneumatic tires, pneumatic tires, and/or other technologies. One example shear band may be constructed as a composite comprised of individual knitted layers, which may be, in turn, constructed from certain materials having specific physical properties that, when combined in a particular manner as described herein, may provide overall physical properties and performance characteristics desirably exceeding that which would be obtained from a shear band constructed from only one of the individual materials. By way of example only, improvements in rolling resistance and tire design flexibility may be obtained.

[0120] Conventional shear band materials may be replaced by ultra-light, three-dimensional, knitted fabric layers, as described herein. In other applications, computerized weft and warp machines may develop three-dimensional textiles with improved physical, thermal, and/or mechanical properties. These textiles may be used in aerospace, automobile, geotechnical, marine, medical, and/or other applicable industries. Within this family of textiles, knitted three-dimensional fabrics may define a structure of two independent top and bottom layers (also called skins) interconnected, but kept apart, by a spacer layer. This type of structure may be manufactured by weft or warp knitting, with warp knitting being most common. During a knitting cycle, the top and bottom layers may be knitted simultaneously using a double-needle machine.

[0121] The example knitted multifilament yarns may define the top and bottom layers, while monofilament yarns (or piles) may define the spacer layer. The example shear band may further comprise a first rubber layer secured to the top layer and a second rubber layer secured to the bottom layer. The shear band may be split at intervals by a material, such as polyurethane or similar fibers. The thickness of the shear band may be between 7.0 mm and 10.0 mm. The multifilament yarns of the top and bottom layers and the monofilament yards of the spacer layer may be formed of polyester or other suitable material.

[0122] As shown in FIGS. 1-2, an example shear band strip 10 in accordance with the present invention may include a first top rubber layer, a first top fabric layer 21 secured to the first top rubber layer, a second bottom rubber layer, a second bottom fabric layer 22 secured to the second bottom rubber layer, and a spacer layer 30 radially interconnecting the first top fabric layer and the second bottom fabric layer. The layers 21, 22, 30 may be split into regular parts by longitudinal spacer sections 40 of elastic polyurethane and/or other suitable material.

[0123] The first top fabric layer 21 and the second bottom fabric layer 22 may be constructed of multifilament yarns of suitable material. Multifilament yarns may be composed of continuous filaments aligned in parallel rows which run straight except when they are coiled by the insertion of a twist, giving the yarns an appearance of evenness or smoothness and an absence of hairiness. Most of the filaments may not require sizing. However, sizing may improve their efficiency by a further 15-20%. Sizing may improve frictional resistance of the yarn and may bond the filaments preventing peeling back and intermingling of any broken filaments which are present on the yarn before weaving or may break during weaving. In order to achieve this, the selected size of the filaments may have sufficient adhesion to the fibers to make the filaments cohere. The multifilament yarns may form a pattern with vacant spaces 23 (FIGS. 1-2) for reducing weight. The vacant spaces 23 may be any suitable shape, such as hexagonal (FIGS. 1-2), square, orthogonal, nonogonal, triangular, etc.

[0124] The example spacer layer 30 may be constructed of monofilament yarns of suitable material. Monofilament yarns may consist of a single solid filament. Monofilament yarns may be circular and solid in cross section. The shape of the filament may be altered to produce noncircular filaments, hollow filaments, and/or other shaped monofilaments. The diameter range of monofilament yarns may be between 100.0 μm and 2000.0 μm. Examples of monofilament yarns may include fishing line, dental floss, sport racquet strings, bristles of tooth brushes, and/or other suitable uses. Hollow monofilaments may be used in softer sewing thread applications while elastomeric monofilaments may find applications in pressure layers, such as the spacer layer 30. The monofilaments of the spacer layer 30 may be attached to the fabric layers 21, 22 in any suitable manner, such as knitting or weaving the monofilaments directly into the fabric layers.

[0125] In accordance with the present invention, a ring-structure 300 may be formed by the shear band strip 10 by stich-knitting an over-lap first extension flap 310 of the first top fabric layer 21 to another, radially outer first portion 211 of the same first top fabric layer 21 so as to construct the helically wound annular ring-structure 300 (FIGS. 3-6). The resulting ring-structure 300 may thereby be axially and circumferentially cut, such as by a blade 601, to form parallel annular rings 611 for use as a shear band for an exemplary tire, such as a non-pneumatic tire shear band or a pneumatic tire belt/overlay structure. The second bottom fabric layer 22 may additionally have a second extension flap 320 for stitch-knitting to another second radially inner portion 212 of the second bottom fabric layer 22 (FIG. 6).

[0126] Stitch-knitting may be conducted with a stich-knitting arm (not shown) entering an interior of the helical structure 300 from one axial end and approaching the second, radially inner extension flap 320 obliquely so that the second, radially inner extension flap 320 be stitched to the same second, radially inner portion 212 of second bottom fabric layer 22 (FIG. 6). The stitch-knitting arm may also proceed axially across an exterior of the helical structure 300 and approaching the first, radially outer extension flap 310 obliquely from one axial end so that the first, radially outer extension flap 310 be stitched to the same first, radially outer portion 211 of first top fabric layer 21 (FIG. 6). These stitch-knitting steps may be conducted in any sequential order. Once the blade 601 separates the rings 611, the rings may thereby form helically secured internally and externally discrete annular rings 611 for use as shear bands and/or belt/overlay structures, as described above.

[0127] The shear band strip 10 may be a composite between a tread and a supporting structure connected to an axle-hub. The shear band strip 10 may be constructed as a ring of rubber or reinforced rubber. The shear band strip 10 may also be constructed of a composite of rubber (an/or reinforced rubber) and other materials. One such material may be a 3D-woven material (FIG. 1). As described above, the shear band strip 10 may be a ring-shaped 3D-fabric material. The 3D-woven material may be constructed on a specialized machine which may introduce filaments via knitting-needles from top and bottom onto a bed of horizontally pre-layered filaments. Thus, there may be no independently generated top or bottom fabrics, but one entire 3D-construction made in step. The extension flaps 310, 320 may be generated by extending the non-3D edges. The shear band strip 10 may thereby comprise a ring-shaped 3D-fabric sandwiched between two rubber layers. The ring-shaped 3D-fabric may be directly connected to a tread-layer and a support-structure.

[0128] One of ordinary skill in the art will understand that numerous examples of the present invention may be created that fall within the present disclosure and claims that follow. It should be understood that the present invention includes various modifications that may be made to the examples described herein that come within the scope of the appended claims and their equivalents, as determined by one of ordinary skill in the art.