Patent Application
20210146719
The present invention relates to wheel/tire assemblies, and more particularly, to non-pneumatic wheel/tire assemblies.
Radial pneumatic tires rely on the ply reinforcement to carry and transfer the load between the rim and the belt layer. These ply cords need to be tensioned to carry the load. Tensioning of these ply cords is achieved with the pressurized air in the inner chamber of the tire. If air pressure is lost, load carrying capacity of a pneumatic tire decreases significantly. Preventing the slow or sudden air pressure loss has been a challenge for the tire makers. One proposed solution is to use non-pneumatic tires. A top loader non-pneumatic tire can perform similar to a pneumatic tire if its durability, speed rating/limit and load capacity can be increased to the levels of a pneumatic tire.
Many top loader non-pneumatic tires rely on the polymeric spokes to carry the load of the vehicle. Spokes transfer the load from the rim to the shear band. Due to the characteristics of the polymeric materials used in the spokes of these tires, performance of these tires are limited. It is an object of the present invention to overcome this limitation and increase the load carrying capacity and durability of these spokes and hence the performance of the top loader non-pneumatic tire.
A wheel assembly in accordance with the present invention includes a mounting plate for attachment to a rotatable axle; a plurality of friction plates each engaging one of a plurality of parts of a tire assembly; and a plurality of cable members each connecting the mounting plate to the tire assembly such that each cable member extends radially outward through a first hole in one of the friction plates and radially inward through a second hole in the one friction plate to form a loop about the one friction plate and the one part of the plurality of parts of the tire assembly.
According to another aspect of the wheel assembly, each cable member extends from each second hole of a corresponding friction plate circumferentially adjacent a radially inner side of the corresponding friction plate.
According to still another aspect of the wheel assembly, each cable member extends from each second hole of a corresponding friction plate radially inward toward a second mounting plate secured to the first mounting plate.
According to yet another aspect of the wheel assembly, each cable member of the plurality of cable members and each friction plate of the plurality of friction plates cooperate with each other to engage the one part of the tire assembly in a mechanically interlocking arrangement.
According to still another aspect of the wheel assembly, each cable member of the plurality of cable members extends radially away from the mounting plate.
According to yet another aspect of the wheel assembly, each cable member extends of the plurality of cable members from each second hole of a corresponding friction plate to converge on that same cable member.
According to still another aspect of the wheel assembly, each cable member of the plurality of cable members extends from each second hole of a corresponding friction plate to that same cable member such that each cable member is fixed to itself.
According to yet another aspect of the wheel assembly, one part of each cable member is fixed to another part of each same cable member by welding.
According to still another aspect of the wheel assembly, one part of each cable member is fixed to another part of each same cable member by an adhesive.
According to yet another aspect of the wheel assembly, one part of each cable member is fixed to another part of each same cable member by fusing the parts together.
A first method in accordance with the present invention rotationally secures a wheel assembly to a tire assembly. The method includes the steps of: extending each cable member of a plurality of cable members radially away from a central plate; extending each cable member of the plurality of cable members radially through a first through-hole in a first end portion of each friction plate of a plurality of friction plates; radially and circumferentially curving each cable member of the plurality of cable members back toward the central plate; extending each cable member of the plurality of cable members radially through a second through-hole in a second end portion of each friction plate of the plurality of friction plates; extending each cable member of the plurality of cable members circumferentially along a radially bottom portion of each friction plate of the plurality of friction plates; extending each cable member of the plurality of cable members to converge on another part of each cable member of the plurality of cable members at an intersection; and securing each cable member of the plurality of cable members to itself at the intersection.
According to another aspect of the first method, the securing step includes fusing each cable member of the plurality of cable members to itself.
According to still another aspect of the first method, the securing step includes molding.
According to yet another aspect of the first method, the securing step includes bolting.
According to still another aspect of the first method, the securing step includes clamping.
A second method in accordance with the present invention rotationally secures a wheel assembly to a tire assembly. The method includes the steps of: extending each cable member of a plurality of cable members radially away a first central plate; extending each cable member of the plurality of cable members radially through a first end portion of each friction plate of a plurality of friction plates; curving each cable member of the plurality of cable members radially and circumferentially back toward a second central plate; and extending each cable member of the plurality of cable members radially through a second end portion of each friction plate of the plurality of friction plates.
According to another aspect of the second method, a further step secures each cable member of the plurality of cable members to a second central plate.
According to still another aspect of the second method, a further secures each cable member of the plurality of cable members to itself.
According to yet another aspect of the second method, a further step molds one part of each cable member of the plurality of cable members to another part of each same cable member of the plurality of cable members.
According to still another aspect of the second method, further steps include securing each cable member of the plurality of cable members to a second central plate; and securing the first central plate to the second central plate.
The present invention will be more clearly understood by the following description of some examples thereof, with reference to the accompanying drawings, in which:
A conventional wheel/tire assembly, such as that described in US 2004/0069385, incorporated herein by reference in its entirety, may have an outer ring, such as a shear band, flexibly connected to a central hub by means of lightweight composite springs. The springs may be plates fixed to the ring and to the hub. The hub may contain a speed reduction gear unit and/or an electric motor and may have a suspension mechanism for connecting a vehicle chassis to each wheel. The ring may be constructed from a flexible composite material, such as carbon fiber reinforced nylon material and have twin rubber tires and a plurality of circumferentially spaced-apart radial cleats which engage the ground and provide improved traction. The hub may also be formed from a carbon fiber reinforced composite material. Another conventional wheel may have a rubber strip with a molded tread bonded to a composite ring for improved grip. Further, the springs interconnecting the ring and hub may be S-shaped lightweight composite springs.
Another conventional wheel/tire assembly may be formed from a lightweight composite material, such as carbon fiber reinforced polyamide. The assembly may have a cylindrical central hub and a circular outer flexible rim mounted on the central hub by an endless looped spring band extending between the central hub and the circular rim. Six radial loops may be defined by the spring band. The spring band may be attached to the central hub and to the circular rim by any suitable means, such as adhesion, cohesion, soldering and/or mechanical fixing by means of bolts, rivets, and/or clamps.
As shown in
The spoke structure 110 may define a plurality of cavities disposed concentrically about the rim allowing the spoke structure to deflect under load thereby defining a suitable balance between flexibility for ride comfort and traction within a footprint of the assembly 140 and stiffness for vehicle handling, low rolling resistance, and low heat build-up within the spoke structure 110. The spoke structure 110 may engage portions of the rim in a mechanical interlocking arrangement. The rim may further include plates that, along with portions of the rim may sandwich portions of the spoke structure 110 and create a further frictional and/or adhesive securement between the rim and the spoke structure. The spoke structure 110 may comprise a homogenous or heterogeneous polymer and/or a filled polymer.
The friction plates 220 may each have a first axial end portion 221 and an opposite second axial end portion 222. Each end portion 221, 222 may have radial through-holes through which one of the cable members 210 may be inserted to form a single loop about a single friction plate 220 and a part of the spoke structure 110 (
The friction plates 420 may each have a first axial end portion 421 and an opposite second axial end portion 422. Each end portion 421, 422 may have radial through-holes through which one of the cable members 410 may be inserted to form a single loop about a single friction plate 220 and a part of the spoke structure 110 (
Variations in the present invention are possible in light of the description of it provided herein. While certain representative examples and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. It is, therefore, to be understood that changes can be made in the particular examples described which will be within the full scope of the present invention as defined by the following appended claims. Further, the present invention is not limited to the examples hereinbefore described which may be varied in both construction and detail within the full scope of the appended claims.
