Roller chain

Roller chain or bush roller chain is the type of chain drive most commonly used for transmission of mechanical power on many kinds of domestic, industrial and agricultural machinery, including conveyors, wire- and tube-drawing machines, printing presses, cars, motorcycles, and bicycles. It consists of a series of short cylindrical rollers held together by side links. It is driven by a toothed wheel called a sprocket. It is a simple, reliable, and efficient means of power transmission.

Though Hans Renold is credited with inventing the roller chain in 1880, sketches by Leonardo da Vinci in the 16th century show a chain with a roller bearing.

Construction of the chain

There are actually two types of links alternating in the bush roller chain. The first type is inner links, having two inner plates held together by two sleeves or bushings upon which rotate two rollers. Inner links alternate with the second type, the outer links, consisting of two outer plates held together by pins passing through the bushings of the inner links. The "bushingless" roller chain is similar in operation though not in construction; instead of separate bushings or sleeves holding the inner plates together, the plate has a tube stamped into it protruding from the hole which serves the same purpose. This has the advantage of removing one step in assembly of the chain.

Roller

The rollers are an Old World family, Coraciidae, of near passerine birds. The group gets its name from the aerial acrobatics some of these birds perform during courtship or territorial flights. Rollers resemble crows in size and build, and share the colourful appearance of kingfishers and bee-eaters, blues and pinkish or cinnamon browns predominating. The two inner front toes are connected, but not the outer one.

They are mainly insect eaters, with Eurystomus species taking their prey on the wing, and those of the genus Coracias diving from a perch to catch food items from on the ground, like giant shrikes.

Although living rollers are birds of warm climates in the Old World, fossil records show that rollers were present in North America during the Eocene. They are monogamous and nest in an unlined hole in a tree or in masonry, and lay 2–4 eggs in the tropics, 3–6 at higher latitudes. The eggs, which are white, hatch after 17–20 days, and the young remain in the nest for approximately another 30 days.

Arthur Ganson

Arthur Ganson (born 1955) is a renowned kinetic sculptor. He makes mechanical art demonstrations and Rube Goldberg machines with existential themes. His moving sculptures have been exhibited at a number of science museums and art galleries. Ganson's work appeals to viewers of all ages, and has been featured in an animated children's television show. He has invented mass-produced children's toys, and hosts an annual competition to make Rube Goldberg chain reaction machines.

Ganson was an artist-in-residence at the Mechanical Engineering department of the Massachusetts Institute of Technology from 1995–1999. In addition, he has given invited presentations about his work at the TED conference, and at the Long Now Foundation.

Biography

Ganson was born in Hartford, Connecticut in 1955. He has an older sister, Ellen Ford and a younger brother, Richard Ganson. He received a Bachelor of Fine Arts degree from the University of New Hampshire in 1978.

Work

Ganson describes his work as a cross between mechanical engineering and choreography. His sculptures have been called "gestural, humorous, evocative, and introspective", or "Ingenious. Philosophical. Witty".