A wheel is a circular component that is intended to rotate on an axle bearing. The wheel is one of the key components of the wheel and axle which is one of the six simple machines. Wheels, in conjunction with axles, allow heavy objects to be moved easily facilitating movement or transportation while supporting a load, or performing labor in machines. Wheels are also used for other purposes, such as a ship's wheel, steering wheel, potter's wheel, and flywheel.
A tire or tyre is a ring-shaped component that surrounds a wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide traction on the surface over which the wheel travels. Most tires, such as those for automobiles and bicycles, are pneumatically inflated structures, which also provide a flexible cushion that absorbs shock as the tire rolls over rough features on the surface. Tires provide a footprint, called a contact patch, that is designed to match the weight of the vehicle with the bearing strength of the surface that it rolls over by providing a bearing pressure that will not deform the surface excessively.
Michelin, in full Compagnie Générale des Établissements Michelin SCA, is a French multinational tyre manufacturing company based in Clermont-Ferrand in the Auvergne-Rhône-Alpes région of France. It is the second largest tyre manufacturer in the world behind Bridgestone and larger than both Goodyear and Continental. In addition to the Michelin brand, it also owns the Kléber tyres company, Uniroyal-Goodrich Tire Company, SASCAR, Bookatable and Camso brands. Michelin is also notable for its Red and Green travel guides, its roadmaps, the Michelin stars that the Red Guide awards to restaurants for their cooking, and for its company mascot Bibendum, colloquially known as the Michelin Man, who is a humanoid consisting of tyres.
Contact patch is the portion of a vehicle's tire that is in actual contact with the road surface. It is commonly used in the discussion of pneumatic tires, where the term is used strictly to describe the portion of the tire’s tread that touches the road surface. The term “footprint” is used almost synonymously. Solid wheels also exhibit a contact patch which is generally smaller than the pneumatic “footprint”.
A radial tire is a particular design of vehicular tire. In this design, the cord plies are arranged at 90 degrees to the direction of travel, or radially. Radial tire construction climbed to 100% market share in North America following Consumer Reports finding the superiority of the radial design in 1968, and were standard by 1976.
André Jules Michelin was a French industrialist who, with his brother Édouard (1859–1940), founded the Michelin Tyre Company in 1888 in the French city of Clermont-Ferrand.
Cooper Tire & Rubber Company is an American company that specializes in the design, manufacture, marketing, and sales of replacement automobile and truck tires, and has subsidiaries that specialize in medium truck, motorcycle, and racing tires. With headquarters in Findlay, Ohio, Cooper Tire has 60 manufacturing, sales, distribution, technical, and design facilities within its worldwide family of subsidiary companies, including the UK-based Avon Tyres brand, which produces tires for motorcycles, road cars, and race cars.
Cornering force or side force is the lateral force produced by a vehicle tire during cornering.
Snow chains, or tire chains, are devices fitted to the tires of vehicles to provide increased traction when driving through snow and ice.
BFGoodrich is an American tire company. Originally part of the industrial conglomerate Goodrich Corporation, it was acquired in 1990 by the French tire maker Michelin. BFGoodrich was the first American tire manufacturer to make radial tires. It made tires for the then new Winton car from Winton Motor Carriage Company.
The rim is the "outer edge of a wheel, holding the tire". It makes up the outer circular design of the wheel on which the inside edge of the tire is mounted on vehicles such as automobiles. For example, on a bicycle wheel the rim is a large hoop attached to the outer ends of the spokes of the wheel that holds the tire and tube. In cross-section, the rim is deep in the center and shallow at the outer edges, thus forming a "U" shape that supports the bead of the tire casing.
A run-flat tire is a pneumatic vehicle tire designed to resist the effects of deflation when punctured, allowing the vehicle to continue to be driven at reduced speeds for limited distances. First developed by tire manufacturer Michelin in the 1930s, run-flat tires were introduced to the public market in the 1980s. They have increased in popularity over time.
A flat tire is a deflated pneumatic tire, which can cause the rim of the wheel to ride on the tire tread or the ground potentially resulting in loss of control of the vehicle or irreparable damage to the tire. The most common cause of a flat tire is puncturing of the tire by a sharp object, such as a nail or pin, letting the air escape. Depending on the size of the puncture, the tire may deflate slowly or rapidly.
Airless tires, non-pneumatic tires (NPT), or flat-free tires are tires that are not supported by air pressure. They can be used on small vehicles such as ride-on lawn mowers and motorized golf carts. They also are used on heavy equipment required to operate on sites where risk of tire punctures is high. Tires composed of closed-cell polyurethane foam are also made for bicycles and wheelchairs.
A bicycle tire is a tire that fits on the wheel of a bicycle or similar vehicle. These tires may also be used on tricycles, wheelchairs, and handcycles, frequently for racing. Bicycle tires provide an important source of suspension, generate the lateral forces necessary for balancing and turning, and generate the longitudinal forces necessary for propulsion and braking. Although the use of a pneumatic tire greatly reduces rolling resistance compared to the use of a rigid wheel or solid tire, the tires are still typically the second largest source, after wind resistance, of power consumption on a level road. The modern detachable pneumatic bicycle tire contributed to the popularity and eventual dominance of the safety bicycle.
The Michelin PAX is an automobile run-flat tire system that utilizes a special type of rim and tire to allow temporary use of a wheel if its tire is punctured. The core of Michelin's PAX system is the semi-rigid ring installed onto the rim using special equipment. It provides support to the tire and its sidewall to allow emergency operation at limited speed until such time as the tire can be replaced. Cars that use the system include supercars like the Bugatti Veyron EB 16.4, luxury cars like the Rolls-Royce Phantom, and more common vehicles like the Honda Odyssey and Nissan Quest.
The following outline is provided as an overview of and topical guide to tires:
The Charles Goodyear Medal is the highest honor conferred by the American Chemical Society, Rubber Division. Established in 1941, the award is named after Charles Goodyear, the discoverer of vulcanization, and consists of a gold medal, a framed certificate and prize money. The medal honors individuals for "outstanding invention, innovation, or development which has resulted in a significant change or contribution to the nature of the rubber industry". Awardees give a lecture at an ACS Rubber Division meeting, and publish a review of their work in the society's scientific journal Rubber Chemistry and Technology.
Timothy B. Rhyne is a retired Michelin Research Fellow and co-inventor of the Tweel.
Steven M. Cron is a retired Michelin product research engineer and co-inventor of the Tweel.
