Patent Publication Number: US-2023150307-A1

Title: Tire structure

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to a pneumatic or non-pneumatic tire, and more particularly, the present invention defines a structure for support an appropriate load for a vehicle. 
     BACKGROUND OF THE INVENTION 
     A conventional non-pneumatic tire for a vehicle may include an inner hub, sometimes referred to as a wheel, surrounded circumferentially by an radially outer disposed tread that includes an annular shear band. The inner hub may be made of metal and have a high degree of conductivity. The non-pneumatic tire may include a series of spokes that are disposed radially between the inner hub and the tread. The spokes can be made of polyurethane and cycle between tension and compression upon every revolution of the tire. A shear band may also be included within the non-pneumatic tire and be located radially between the spokes and the tread. 
     As this type of non-pneumatic tire rotates under load, the spokes experience bending, extension, and compression deformation when they are located downward near the contact patch of the tread. The spokes straighten outside the contact patch relieving the bending and compression deformation. The spokes thus experience cyclic deformation as the tire rotates. These repeated deformation cycles may cause fatigue in the spokes and limit the life of the spokes and the non-pneumatic tire. 
     SUMMARY OF THE INVENTION 
     A tire in accordance with the present invention includes a radially inner annular rim with a central axis, an annular shearband disposed radially outward from the inner rim, an annular supporting structure disposed radially outward from the inner rim, the supporting structure radially interconnecting the inner rim and the shearband, and an annular tread disposed radially outward from the shearband. The supporting structure includes a plurality of spokes each having a radially outer teardrop loop and a radially inner triangular structure with a radially inner vertex of the teardrop loop and a radially outer vertex of the triangular structure converging at a single location. A ratio of a maximum radial height of the teardrop loop to a maximum circumferential width of the teardrop loop is in a range between 0.99 and 0.50. 
     According to another aspect of the tire, the supporting structure includes between 4 and 80 spokes. 
     According to still another aspect of the tire, the supporting structure includes between 20 and 60 spokes. 
     According to yet another aspect of the tire, the supporting structure includes between 30 and 50 spokes. 
     According to still another aspect of the tire, the supporting structure includes 40 spokes. 
     According to yet another aspect of the tire, the supporting structure includes 36 spokes. 
     According to still another aspect of the tire, each spoke is symmetric about a radially extending midplane of each spoke. 
     According to yet another aspect of the tire, each spoke has a radially outward-facing fish-like structure. 
     According to still another aspect of the tire, each triangular structure has two angled legs. 
     According to yet another aspect of the tire, each spoke has a uniform construction. 
     According to still another aspect of the tire, a first spoke has a first construction and a second spoke has a second, different construction. 
     According to yet another aspect of the tire, each spoke has a uniform axial width. 
     According to still another aspect of the tire, the ratio is in a range between 0.99 and 0.50. 
     According to yet another aspect of the tire, the ratio is in a range between 0.90 and 0.60. 
     According to still another aspect of the tire, the ratio is in a range between 0.80 and 0.70. 
     According to yet another aspect of the tire, a maximum circumferential width of each triangular structure is greater than the maximum circumferential width of the teardrop loop. 
     A method in accordance with the present invention supports part of a vehicle load. The method incudes the steps of: extending a radially inner annular rim circumferentially about a central axis; extending an annular shearband circumferentially about the central axis; radially interconnecting the inner rim and the shearband with an annular supporting structure; extending an annular tread circumferentially radially outward from the shearband; and converging a radially inner vertex of a teardrop loop of the supporting structure and a radially outer vertex of a triangular structure of the support structure at a single location. 
     According to another aspect of the method, a further step incudes defining a ratio of a maximum radial height of a teardrop loop of the supporting structure to a maximum circumferential width of the teardrop loop in a range between 0.99 and 0.50. 
     According to still another aspect of the method, further steps include defining a first construction of a first spoke of the supporting structure and defining a second different construction of a second spoke of the support. 
     According to yet another aspect of the method, a further step includes defining the supporting structure spokes having radially outward-facing fish-like structures symmetric about a radial midplane. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, which references the appended Figures, in which: 
         FIG.  1    is a schematic side view of an example tire in accordance with the present invention. 
         FIG.  2    is a schematic side view of an example tire functionally similar the tire of  FIG.  1   . 
         FIG.  3    is a schematic perspective view of another example tire functionally similar to the tire of  FIG.  1   . 
         FIG.  4    is a schematic side view of the tire of  FIG.  3   . 
         FIG.  5    is a schematic cross-sectional view of another portion of the tire of  FIG.  3   . 
         FIG.  6    is a schematic enlarged side view of part of the tire of  FIG.  1   . 
     
    
    
     Repeated use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention. 
     DETAILED DESCRIPTION OF EXAMPLES OF THE PRESENT INVENTION 
     Reference will now be made in detail to examples of the present invention, one or more examples of which are illustrated in the above-described drawings. 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 and/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. 
     U.S. Pat. No. 9,027,615, hereby incorporated herein in its entirety, describes a representative example pneumatic tire for use with the present invention. U.S. Pat. No. 10,926,581, hereby incorporated herein in its entirety, describes a representative example non-pneumatic tire for use with the present invention. U.S. Patent Publication No. 2017/0368879, hereby incorporated herein in its entirety, describes another representative example non-pneumatic tire for use with the present invention. 
     As shown in  FIG.  2   , an example non-pneumatic tire  200  functionally similar to the tire of  FIG.  1    may have one or more spoke disks  210  axially, radially, and rotationally aligned with each other. The spoke disks  210  may bend or deform axially outward, while the spoke disks may also bend in an angular plane. The spoke disks  210  may be laterally stiff so that they can be combined to tune the tire axial stiffness. 
     As shown in  FIG.  3   , another example non-pneumatic tire  10  functionally similar to the tire of  FIG.  1    may have a static discharge element  30  for use in conducting electricity through the tire  10  to prevent or reduce the chances of shocking a person touching the vehicle and to remove unwanted static electricity from the vehicle. The static discharge element  30  may be located at the supporting structure  22  of the non-pneumatic tire  10  in order to transfer the electricity across the supporting structure  22 . The supporting structure  22  may be constructed of materials that have poor electrically conductive properties. The static discharge element  30  may be electrically conductive and may be made in a variety of manners. In some examples, the static discharge element  30  may be elastic so that it may deflect with supporting structures  22  that are likewise elastic. 
     The non-pneumatic tire  10  may have an axis of rotation about the central axis  14 . The central axis  14  may extend in an axial direction  16  of the tire  10 . The central axis  14  may extend through an opening of a hub  12  of the tire  10 . The radial direction of the tire  10  may be oriented at a perpendicular angle to the central axis  14 , such that the hub  12  is spaced radially inwards from other portions of the tire  10 , such as the supporting structure  22  and the tread  16 . The non-pneumatic tire  10  may also have a circumferential direction  20  about which various portions of the tire  10  extend. For example, the tread  26 , shear band  24 , supporting structure  22 , and hub  12  may all extend 360 degrees in the circumferential direction  20  about the central axis  14 . 
     The supporting structure  22  may engage the hub  12  and be located outward from the hub  12  in the radial direction  18 . The supporting structure  22  may include a series of spokes  28  extending from the hub  12  to the shear band  24  in the radial direction  18 . It is to be understood that the supporting structure  22  need not include spokes  28 . For example, the supporting structure  22  may be made of a series of elements arranged into a honeycomb like structure that extends 360 degrees about the central axis  14 . In another example, the supporting structure  22  may be a solid member that extends 360 degrees about the central axis  14  in the circumferential direction  20 . 
     The supporting structure  22  may have a first radial end  32  at the hub  12  that coincides with a first radial terminal end  36  of the spoke  28 . The spoke  28  may extend in the radial direction  18  to the shear band  24 , in which a second radial end  34  of the supporting structure  22  may be located. As the spoke  28  terminates at/in the shear band  24 , the second radial terminal end  38  of the spoke  28  may similarly be located at the second radial end  34 . The shear band  24  may be located outward from the various spokes  28  in the radial direction  18  and may extend 360 degrees about the central axis  14  in the circumferential direction  20 . The tread  26  of the example non-pneumatic tire  10  may be outward from the shear band  24  in the radial direction  18  and may extend completely around the central axis  14  in the circumferential direction  20 . 
     The spoke  28  may flex during rotation of the tire  10  and the spoke  28  may have an elongation of 10 percent, 0-4 percent, 4-5 percent, 5-15 percent, 8-12 percent, 9-11 percent, 10-13 percent, 10-15 percent, 15-25 percent, up to 30 percent, or up to 50 percent. The spoke  28  may be made of polyurethane and thus may not have adequate electrical conductivity. 
     As shown in  FIG.  5   , an alternative arrangement of an example non-pneumatic tire  10  may include a static discharge element  30  including a filament fiber filler  68  injected into the other material of the supporting structure  22 . The supporting structure  22  may have an inner interface ring  40 , an outer interface ring  44 , and a plurality of spokes  28 . These components  28 ,  40 ,  44  may be constructed of polyurethane with a filler made up of the filament fibers  68 . The filament fibers  68  may be mixed into the polyurethane and distributed about the components  28 ,  40 ,  44 . In other examples, the components  28 ,  40  and  44  and any other portions of the supporting structure  22  may be made of reinforced and/or non-reinforced material, such as a polymeric material. The polymeric material may be polyurethane, co-polyester, polyether block amide, and/or polyolefins. Still further, other examples of the non-pneumatic tire  10  as described herein may include components, such as the spoke  28 , the inner interface ring  40 , the outer interface ring  44 , and the supporting structure  22 , with different types of polymeric materials. 
     As shown in  FIGS.  1  and  6   , in accordance with the present invention, a tire  600  may have a radially inner first rim  601 , a radially outer second rim  602 , and a top loaded connecting structure  610  interconnecting the first rim  601  and the second rim  602 . Such a connecting structure  610  may be more flexible/compliant than the above described conventional tires. The connecting structure  610  may include a plurality of load bearing elements, or spokes  620 . The connecting structure  610  may include between 4 and 80, between 20 and 60, between 30 and 50, about 40, and/or about 36 ( FIG.  1   ) elements  620 , depending on load requirements, dimensions, materials, spoke configurations, etc. 
     Each element  620  may be symmetric about a radially extending midplane  622  and have a radially outward-facing fish-like structure. Each element  620  may include a radially outer teardrop loop  624  and a radially inner triangular structure  628  having two angled legs. A radially inner vertex of the teardrop loop  624  and a radially outer vertex of the triangular structure  628  may converge/meet at a single location  630 . This connecting structure  610  may show improved fatigue life compared to the conventional designs. The elements  620  may be scalable to any tire/rim and provide lower hysteresis/heat build-up and little, if any, snapping effect on failure. More importantly, this connecting structure  610  may provide ride/handling performance and load-bearing capability comparable to current high performance passenger tires. 
     The elements  620  may be uniform ( FIG.  1   ) or varied (not shown) with axial widths that may be the full width of the tire  600 . The maximum radial height  625  of the tear drop loop  624  may be greater than or equal to the maximum circumferential width  626  of the teardrop loop  624 . The ratio of the maximum radial height  625  to the maximum circumferential width  626  may be in the range between 1.00 and 0.50, 0.99 and 0.50, 0.90 and 0.60, 0.80 and 0.70, and/or about 0.75. The circumferential width  629  of the triangular structure  628  may be greater than ( FIG.  6   ), less than, or equal to the circumferential width  626  of the teardrop loop  624 . 
     While the present invention has been described in connection with certain preferred examples, it is to be understood that the subject matter encompassed by way of the present invention is not to be limited to those specific examples. On the contrary, it is intended for the subject matter of the present invention to include all alternatives, modifications, and/or equivalents as may be included within the spirit and scope of the following claims.