Water wheel

A water wheel is a machine for converting the energy of free-flowing or falling water into useful forms of power, often in a watermill. A water wheel consists of a large wooden or metal wheel, with a number of blades or buckets arranged on the outside rim forming the driving surface. Most commonly, the wheel is mounted vertically on a horizontal axle, but the tub or Norse wheel is mounted horizontally on a vertical shaft. Vertical wheels can transmit power either through the axle or via a ring gear and typically drive belts or gears; horizontal wheels usually directly drive their load.

Water wheels were still in commercial use well into the 20th century, but they are no longer in common use. Prior uses of water wheels include milling flour in gristmills and grinding wood into pulp for papermaking, but other uses include hammering wrought iron, machining, ore crushing and pounding fiber for use in the manufacture of cloth.

Some water wheels are fed by water from a mill pond, which is formed when a flowing stream is dammed. A channel for the water flowing to or from a water wheel is called a mill race (also spelled millrace) or simply a "race", and is customarily divided into sections. The race bringing water from the mill pond to the water wheel is a headrace; the one carrying water after it has left the wheel is commonly referred to as a tailrace.

Millwheel

Millwheel or water wheel are sometimes used as a charge in heraldic arms. The water wheel is often used to symbolize the food processing industry or industry in general.

The heraldric millwheel is usually stylized and may look different in the heraldic traditions of different countries.

Examples

Mühldorf am Inn (canting, since the name means "Mill village on the Inn")

Mühldorf am Inn (canting, since the name means "Mill village on the Inn")

The arms of Bonsmoulins, France, with a millwheel in the base

The arms of Bonsmoulins, France, with a millwheel in the base

The arms of La Courneuve, France, with a millwheel in the door opening

The arms of La Courneuve, France, with a millwheel in the door opening

Nacka, Sweden (Swedish variant)

Nacka, Sweden (Swedish variant)

Forssa, Finland

Forssa, Finland

Bolivar family in Biscaya

Bolivar family in Biscaya

See also