Patent Application
20180326785
The present invention relates generally to wheels.
The general concept of the wheel has been known since antiquity, and has evolved from wood, to metal and composites. Coverings for wheels were also developed over time. For example, where the oldest wheels were formed of wood or metal that made direct contact with the ground, leather and eventually rubber were added to the circumference of the wheel to dampen transmission of impact forces as the wheel traverses irregular terrain or surface debris. Heavier load products (e.g., bikes, heavier duty wheelbarrows, and cars) typically have wheels utilizing air-filled inflated tires. Lighter load products (e.g., suitcases, carts, and mobile toolboxes) typically utilize casters or wheels of simpler construction, such as being formed from metal, plastic, rubber, or a simple combination thereof.
Among other things, the present application relates to an improved molded wheel.
According to one aspect of this disclosure, a wheel includes a main hub portion having an outer portion and an inner portion, the inner portion being spaced from the outer portion by a main hub sidewall. The wheel also includes a ring portion configured to engage the main hub portion so as to enclose the outer portion and the inner portion and create an enclosed void between the main hub portion and the ring portion. The wheel further includes an exterior covering surrounding at least part of the main hub portion and the ring portion at the enclosed void.
According to another aspect of this disclosure, a method of forming a wheel includes forming a main hub portion having an outer portion and an inner portion, the inner portion being spaced from the outer portion by a main hub sidewall. The method also includes forming a ring portion configured to engage the main hub portion so as to enclose the outer portion and the inner portion and create an enclosed void between the main hub portion and the ring portion. The method additionally includes assembling the main hub portion and the ring portion into an assembled hub. The method further includes overmolding an exterior covering surrounding at least part of the main hub portion and the ring portion of the assembled hub.
These and other objects, features, and characteristics of the present invention, as well as the methods of operation and functions of the related elements of structure and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following description and the appended claims with reference to the accompanying drawings, all of which form a part of this specification, wherein like reference numerals designate corresponding parts in the various figures. In one embodiment of the invention, the structural components illustrated herein are drawn to scale. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only, and are not intended as a definition of the limits of the invention. In addition, it should be appreciated that structural features shown or described in any one embodiment herein can be used in other embodiments as well. As used in the specification and in the claims, the singular form of “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise.
Features of utility knives in accordance with one or more embodiments are shown in the drawings, in which like reference numerals designate like elements. The drawings form part of this original disclosure in which:
As may be appreciated from
It may be appreciated from the sectional view of
As further shown in
It may be appreciated that in some embodiments, the assembly of the ring portion 30 and the main hub portion 20 may facilitate injection molding or overmolding of the exterior covering 50 (e.g., as a thermoplastic elastomer) over both opposing sidewalls 145a and 145b of the assembled hub 40 without requiring a core (e.g., a metal core) to support the injection mold. It may be appreciated in some embodiments that the assembled hub 40 may itself serve as the core that supports the injection molding of the exterior covering 50 around the exterior perimeter of the assembled hub 40. It may also be appreciated that the injection molding or other application of the exterior covering 50 may further secure the ring portion 30 to the main hub portion 20. In some embodiments where the components of the assembled hub 40 are themselves molded (e.g., molded polypropylene), it may be appreciated that the wheel 10 may be formed by molding the main hub portion 20 and the ring portion 30 separately, assembling the ring portion 30 into the main hub portion 20 to form the assembled hub 40, and the n molding the exterior covering 50 (e.g., injection molded thermoplastic elastomer) onto the assembled hub 40.
As noted above, in some embodiments, the assembled hub 40 may have one or more enclosed voids therein formed by the enclosure of the space 60. Such enclosed voids may therefore be understood as being bounded between a) the combination of the outer portion 70 of the main hub portion 20 and the flange 110 of the ring portion 30 towards the exterior of the assembled hub 40, b) the inner portion 80 of the main hub portion 20 towards the interior of the assembled hub 40, c/d) the opposing sidewalls of the main hub portion 20 and the ring portion 30, and in some embodiments e/f) pairs of the pillars 100 where the space 60 is subdivided into space segments 90 to form separate enclosed voids. In some embodiments one or more of the enclosed voids may be sealed closed as part of the assembly process (e.g., sealed through application of the exterior covering 50 or through application of a separate sealant). In some embodiments, the combination of the exterior covering 50 over the enclosed voids may provide additional resilience of the wheel 10, which may allow the wheel 10 to mimic an air filled tire. In some embodiments, the engagement of the flange 110 supported by the projection 130 extending over the enclosed void may further facilitate compression into the enclosed void. Regardless, it may be appreciated through the various views of the wheel 10 as assembled, as depicted in
It may be appreciated that the main hub portion 20, the ring portion 30, and the exterior covering 50 may each be formed themselves as assemblies in some embodiments. For example, in an embodiment a plurality of subcomponents may form the ring portion 30 that may then be assembled into the main hub portion 20 (which itself may be an integral body or may be an assembly of subcomponents) to form the assembled hub 40. In another embodiment, a plurality of subcomponents form the main hub portion 20 into which either an integral or an assembled ring portion 30 may be assembled therein to form the assembled hub 40. Subassembly components of the wheel 10 may be coupled together by any appropriate mechanism (e.g., via snap fit, friction fit, adhesives, sealants, welds, screws, bolts, rivets, etc.). In an embodiment the components of the wheel 10 may be formed of a uniform construction (e.g., components may be cast, molded, etc.).
It may be appreciated that the components described herein may be of different constructions or configurations, including but not limited to one or more being comprised of different material choices. For example, the components described herein may each be constructed from a variety of materials, including but not limited to one or more plastics, metals, rubbers, elastomers, or any other appropriate material choice. For example, in an embodiment one or more of the components may be formed of plastic, aluminum (e.g., machined aluminum), iron (e.g., steel), or any other appropriate material. In some embodiments, the material choices may differ from component to component. For example, as described above, in an embodiment, one or more of the main hub portion 20 and the ring portion 30 may be formed of polypropylene, while the exterior covering may be formed by a thermoplastic elastomer. In other embodiments, other materials may be used in any of the components of the assembled hub 40, and/or other materials may be used for the exterior covering 50.
Although aspects of the invention have been described in detail for the purpose of illustration based on what is currently considered to be the most practical and preferred embodiments, it is to be understood that such detail is solely for that purpose and that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover modifications and equivalent arrangements that are within the spirit and scope of the appended claims. For example, it is to be understood that the present invention contemplates that, to the extent possible, one or more features of any embodiment can be combined with one or more features of any other embodiment.
