A ceiling fan is a device suspended from the ceiling of a room, which employs hub-mounted rotating paddles to circulate air in order to produce a cooling effect.
History
The first ceiling fans appeared in the 1860s and 1870s, in America. At that time, they were not powered by any form of electric motor. Instead, a stream of running water was used, in conjunction with a turbine, to drive a system of belts which would turn the blades of two-blade fan units. These systems could accommodate several fan units, and so became popular in stores, restaurants, and offices. Some of these systems still survive today, and can be seen in parts of the southern United States where they originally proved useful.
Contrary to popular belief, the electrically-powered ceiling fan was not invented in 1886 by father-and-son team John and James Hunter[1]. In reality, it was invented four years earlier, by Philip Diehl (pronounced the same as "deal"). Diehl had engineered the electric motor used in the first Singer sewing machines, and in 1882 adapted that motor for use in a ceiling-mounted fan. "The Diehl Electric Fan", as it was known, operated like a common modern-day ceiling fan; each fan had its own self-contained motor unit, eliminating the need for costly and bulky belt systems.
Diehl was, almost immediately, up against fierce competition due to the commercial success of the ceiling fan. However, he continued to make improvements to his invention. One such improvement, the "Diehl Electrolier", was of a light kit adapted onto the ceiling fan to compensate for any light fixture(s) displaced by the installation of the ceiling fan.
By World War I, most ceiling fans were being manufactured with four blades instead of the original two. This change allowed the fan to circulate more air, thereby making more efficient use of its motor.
By the 1920s, ceiling fans had become commonplace in the United States, and had started to take hold internationally. However, during the Great Depression, ceiling fans faded out of vogue in the U.S. By the end of World War II, and into the 1950s, ceiling fans had become almost non-existent. Those which remained were considered items of nostalgia. However, the ceiling fan was still very popular in other countries, notably those with warm climates which could not afford high-energy-consuming devices such as air conditioning.
In the 1960s, some Asian manufacturers started exporting their ceiling fans to the United States. They caught on slowly at first, but found great success during the energy crisis of the late 1970s because ceiling fans consume far less energy than air conditioning units.
Due to this renewed commercial success, many American manufacturers started to produce (or significantly increase production of) ceiling fans. The well-known Casablanca Fan Company was founded in 1974. Other popular American manufacturers at the time included the Hunter Fan Co. (which was then a division of Robbins & Myers, Inc), FASCO (F. A. Smith Co.), Emerson Electric, and Lasko; those latter two were often re-labeled and sold by Sears-Roebuck.
During the rest of the 1970s, and through to the late 1980s, ceiling fans remained popular in the American market. Many small American manufacturers, most of them rather short-lived, started making and selling ceiling fans. Throughout the 1980s, the balance of sales between American-made ceiling fans and those imported from overseas manufacturers changed dramatically. The high cost of American parts and labor became prohibitive for many consumers (for example, a basic American-made ceiling fan could cost anywhere from $150 to $250, whereas the cost of an imported fan would be closer to $25 to $80).
Due to the ever-reducing cost of amenities such as air conditioning, ceiling fan sales once again started to decline, beginning in the early-to-mid 1990s. With the reduction in sales came a reduction in research and development, as well as features. Once-standard features (such as solid wood blades, built-in variable-speed dials, high-quality stator/rotor ("stack") motors, and die-cast steel construction) have been largely replaced by cheap, standardized parts.
While a few companies still offer high-quality ceiling fans, the majority of fans sold today consist of: (a) a poorly-ventilated import motor, (b) particle-board blades with a computer-printed plastic design finish, and (c) a stylized decorative motor encasement ("housing") and adornments. All of these fans cost the same approximate amount to produce, since the motors and blade materials are all standardized and widely available.
Uses
Most ceiling fans can be used in two different ways; that is, most fans have a mechanism, commonly an electrical switch, for reversing the direction in which the blades rotate.
In summer, when the fan's direction of rotation is set so that air is blown downward (typically counter-clockwise, when standing under the fan and looking upwards), the breeze created by a ceiling fan speeds the evaporation of sweat on human skin, which is experienced as a cooling effect.
In winter, buildings in colder climates are usually heated. Air naturally stratifies--that is, warmer air rises to the ceiling while cooler air sinks to the floor. A ceiling fan, with its direction of rotation set so that air is drawn upward (typically clockwise, when standing under the fan and looking upwards), takes cool air from lower levels in the room and pushes it upward towards the ceiling. The warm air, which naturally rises to the ceiling, is forced out of the way of the incoming cool air: it travels along the ceiling and down the walls, to lower levels where people in the room can feel it. This heat-reclaiming action allows for cost reduction, by making it so that less fuel needs to be expended in order to heat the room to a comfortable temperature and keep it there.
Hunter Ceiling Fan
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