Patent Application
20100123350
The present invention relates to automotive road wheels and more particularly pertains to a wheel and method for achieving a rotationally balanced tire/wheel assembly.
Proper rotational balance of an automobile's tires is essential in order to provide a smooth ride, optimize handling characteristics, minimize wear and tear to the vehicle and extend the service life of the tires. A tire is normally balanced after its mounting to a wheel by the attachment of weight to the wheel. The balancing procedure typically includes the steps of spinning the tire/wheel assembly up to speed, measuring forces generated by any imbalance, determining the amount of weight and the precise placement of such weight necessary to counteract the measured forces and crimping the required weight to the wheel's outer edges or adhesively securing the weights to the wheel. The assembly is then again spun up to speed to confirm that proper balance has been achieved. Occasionally, the entire balancing procedure must be repeated if a further readjustment is found to be necessary.
Repeating the above-described procedure for every tire of every vehicle manufactured in a modern high-speed automobile assembly line amounts to a significant effort. Any reduction in such an expense would of course be advantageous. Reducing the amount of weight necessary or obviating the need to actually add balancing weight to a significant portion of a manufacturing line's throughput would in fact constitute such an improvement.
Eliminating the balancing weights from a wheel provides the secondary benefit of enhancing the aesthetic appearance of the wheel as the lead weights normally crimped onto or adhered to the outboard side of the wheel are generally considered unsightly.
Although wheels can be produced to very exacting standards with respect to rotational balance, it is much more difficult if not impossible to manufacture a balanced tire. The complex internal structure of modern tires defies efforts to achieve an even weight distribution from the outset while the elastic nature of the tire makes it difficult to predict, let alone compensate for, the distortion and its commensurate effect on balance caused by the extremely high g-forces a tire is subjected to at highway speeds. Producing a finely balanced tire to be mounted to a finely balanced wheel in order to yield a balanced tire/wheel assembly is therefore not a viable approach towards minimizing the labor normally expended in balancing an automobile's tires. Tire manufacturers do however have the ability to statically test each tire for imbalance and mark the tire carcass to indicate the location of the highest or lowest concentration of weight.
An alternative approach is therefore called for that provides a rotationally balanced tire/wheel assembly which requires only a minimal amount of weight addition and in a significant number of incidents, obviates the need to add any extraneous balancing weights whatsoever.
U.S. Pat. No. 3,913,980 discloses a user installable system of improved automobile wheel and tire dynamic balancing apparatus selectively positioned in the central longitudinal groove-way cavity of the wheel rim for a pneumatic tire.
U.S. Pat. No. 5,271,663 discloses an automotive roadwheel of preselected rotational imbalance, the amount of imbalance being selected to coincide with the average amount of imbalance inherent in the tires to be mounted to the wheel and the orientation of the imbalance being readily discernable such as by coinciding with the location of the valve stem. The method calls for the heaviest orientation of the wheel to be aligned with the lightest orientation of the tire (or vice versa) during the mounting process to yield a balanced tire/wheel assembly without the need to add balancing weight in the majority of such assemblies.
U.S. Pat. No. 6,318,446 discloses a one piece cast wheel having a lightener recess formed in the wheel disc which extends axially beneath the wheel outboard tire bead seat. A method of casting such a one piece wheel which utilizes a multi-piece wheel mold having side members includes a plurality of components. A core for forming the lightener cavity is formed integrally with the side member components. The side member components are sequentially moved relative to each other to release the core from the lightener cavity.
A wheel for a tire may include a rim element for placement of the tire, a central element to cooperate with the rim element and the rim element having a first drop center section and a second drop center section.
The second drop center section and the central element may cooperate to form a junction section having an enclosed circular balancing tube for a spatially balancing weight.
The second drop center section may include a circular balance tube for a spatially balancing weight.
The first drop center section may include a second circular balancing tube for a second spatially balancing weight.
The first circular balancing tube may be a depression in the junction section.
The rim element may include an inner flange element, and the rim element may include an outer flange element.
The center element may include a hub section, and the center element may include a lug hole.
The invention may be understood by reference to the following description taken in conjunction with the accompanying drawings, in which, like reference numerals identify like elements, and in which:
The components of the balancer of the present invention which may include rings, weights fluid and adhesives may be inert after manufacture. This allows little or no environmental impact to the accident site if an accident should occur which could compromise and/or damage the balancing system of the present invention.
The balancing system may be employed in consumer, performance, commercial and industrial wheel types which may include automobile, light-truck and semi truck wheels or other types of wheels.
The grooves may be manufactured into the wheel itself.
These grooves/cavities can be placed in any suitable location about or in the wheel to ensure proper balance, giving consideration to the width, diameter, offset, drop center, anticipated tire size and other imbalance correction design parameters.
The positioning of the balance system groups may also be placed to take into consideration the necessary clearances between the wheel and brake caliper.
The balance system may be used on cast or billet wheel designs or other types of wheel designs.
The balancer rings or ring may be an integral part of the wheel and may be hidden to the user or viewer when being observed from the outside or streetside of the wheel.
The balancer tubes may be protected by the cavity from damage from road debris and maintenance handling.
For use on wider large wheels, depending on the offset, it may be possible to use multiple balancers and may have two or more grooves. The multiple balancers and grooves may be positioned at different positions in order to near maximize the effect of the balancing system.
The balance system may correct imbalances not only of the wheel/tire assembly but all the components that may rotate on the bearings and may include the hub, break disc/drum and wheel/tire assemblies combined.
The balance system may allow the tire to run at lower temperatures which may result from the decreased vibration due to the improved tolerance of the over all balancing and improved tolerance of overall balance which may promote a longer tire life and increase safety.
The balance system of the present invention may continuously adjust the balance as a result of changes in balance due to tire wear, brake rotor or brake drum wear and the accumulation of road grime or mud or other factors in accordance with the design limits of the balancing system.
The balance system may reduce the handling damage to the wheel assembly from maintenance employees because the present invention eliminates the need to place the wheel/tire assembly on a shaft type balancer and should eliminate the need to use lead or other weights which have to be manually applied to the rim.
The balance system may reduce the external balance weights from being prematurely removed from the wheel and consequently may ensure that the wheel would or will remain in balance under most conditions and may prevent damage to other vehicles or to the vehicle itself when these weights are prematurely removed.
The center element 109 of wheel 100 may include a centrally disposed hub section 117 that may facilitate the mounting of wheel 100 to a vehicle's hub. The hub section 117 has a substantially flat inboard mating surface 119 and may be perforated by a central hub hole 133 and a plurality of lug holes 131. In the embodiment illustrated, a plurality of spokes 135 interconnect the hub section 117 with the rim element 107. Aesthetic considerations typically dictate the particular configuration of this part of the wheel and various spoke designs as well as flat solid disks, disks with various patterns of perforations therein and basket-weave type designs are common.
The center element 109 of wheel 200 may include a centrally disposed hub section 117 that may facilitate the mounting of wheel 100 to a vehicle's hub. The hub section 117 has a substantially flat inboard mating surface 119 and may be perforated by a central hub hole 133 and a plurality of lug holes 131. In the illustration, a plurality of spokes 135 interconnect the hub section 117 with the rim element 107. Aesthetic considerations typically dictate the particular configuration of this part of the wheel and various spoke designs as well as flat solid disks, disks with various patterns of perforations therein and basket-weave type designs are common.
The center element 109 of wheel 300 may include a centrally disposed hub section 117 that may facilitate the mounting of wheel 300 to a vehicle's hub. The hub section 117 has a substantially flat inboard mating surface 119 and may be perforated by a central hub hole 133 and a plurality of lug holes 131. In the illustration, a plurality of spokes 135 interconnects the hub section 117 with the rim element 107. Aesthetic considerations typically dictate the particular configuration of this part of the wheel and various spoke designs as well as flat solid disks, disks with various patterns of perforations therein and basket-weave type designs are common.
The center element 109 of wheel 400 may include a centrally disposed hub section 117 that may facilitate the mounting of wheel 400 to a vehicle's hub. The hub section 117 has a substantially flat inboard mating surface 119 and may be perforated by a central hub hole 133 and a plurality of lug holes 131. In the illustration, a plurality of spokes 135 interconnects the hub section 117 with the rim element 107. Aesthetic considerations typically dictate the particular configuration of this part of the wheel and various spoke designs as well as flat solid disks, disks with various patterns of perforations therein and basket-weave type designs are common.
The above described tubes and depressions of the present invention can be formed by a variety of methods. In the case of a cast wheel, for example, appropriate protrusions can be formed in the molds into which the aluminum alloy is cast in order to form the cavities in the resulting wheel. Alternatively, the above depressions can be machined into a wheel after completion of its initial manufacturing process.
While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed.
