Instruct: Given a question, retrieve relevant passages that can help answer the question.
Query: Who invented air conditioning?
The inventor Ding Huan (fl. 180 AD) of the Han dynasty invented a rotary fan for air conditioning, with seven wheels 3 m (10 ft) in diameter and manually powered. In 747, Emperor Xuanzong had a "Cool Hall" built in the imperial palace, which the "Tang Yulin" () describes as having water-powered fan wheels for air conditioning as well as rising jet streams of water from fountains. During the subsequent Song dynasty, written sources mentioned the air conditioning rotary fan as even more widely used.
A thermostat is a device for regulating the temperature of a system so that the system's temperature is maintained near a desired setpoint temperature. The thermostat does this by switching heating or cooling devices on or off, or regulating the flow of a heat transfer fluid as needed, to maintain the correct temperature. The thermostat was invented in 1883 by Warren S. Johnson.
Meanwhile, electric ceiling fans became very popular in other countries, particularly those with hot climates, such as India and the Middle East, where a lack of infrastructure and/or financial resources made energy-hungry and complex freon-based air conditioning equipment impractical. In 1973, Texas entrepreneur H. W. (Hub) Markwardt began importing highly efficient ceiling fans to the United States that were manufactured in India by Crompton Greaves, Ltd. Crompton Greaves had been manufacturing ceiling fans since 1937 through a joint venture formed by Greaves Cotton of India and Crompton Parkinson of England, and had perfected the world's most energy efficient ceiling fans thanks to its patented 20 pole induction motor with a highly efficient heat-dissipating cast aluminum rotor. These Indian manufactured ceiling fans caught on slowly at first, but Markwardt's Encon Industries branded ceiling fans (which stood for ENergy CONservation) eventually found great success during the energy crisis of the late 1970s and early 1980s, since they consumed far less energy (under 70 watts of electricity) than the antiquated shaded pole motors used in most other American made fans. The fans became very effective energy saving appliances for residential and commercial use by supplementing expensive air conditioning with a cooling wind-chill effect. Fans used for comfort create a wind chill by increasing the heat transfer coefficient, but do not lower temperatures directly.
Due to this renewed commercial success using ceiling fans effectively as an energy conservation application, many American manufacturers also started to produce, or significantly increase production of, ceiling fans. In addition to the imported Encon ceiling fans, the Casablanca Fan Company was founded in 1974. Other American manufacturers of the time included the Hunter Fan Co. (which was then a division of Robbins & Myers, Inc), FASCO (F. A. Smith Co.), and Emerson Electric; which was often branded as Sears-Roebuck.
The thermoscope, or Galileo thermometer, was constructed by Galileo Galilei in 1607. In 1643, Evangelista Torricelli invented the mercury barometer. Blaise Pascal (in 1648) rediscovered that atmospheric pressure decreases with height, and deduced that there is a vacuum above the atmosphere.
In 1947, the company produced the first commercial upright freezer. Two years later, the Amana Society sold off the Electrical Department to an investment group organized by Foerstner. Renamed Amana Refrigeration, Inc., the company grew to manufacture refrigerators and air conditioners. The Raytheon Corporation purchased Amana Refrigeration on January 1, 1965, although the Amana division was mostly autonomous. Amana produced the first practical commercial microwave oven in 1967. The division was sold to Goodman Global in 1997 and then sold to Maytag in 2001. It became part of the Whirlpool Corporation when it purchased Maytag in 2006.
A vacuum coffee maker brews coffee using two chambers where vapor pressure and vacuum produce coffee. This type of coffee maker is also known as "vac pot", "siphon" or "syphon coffee maker," and was invented by Loeff of Berlin in the 1830s. These devices have since been used for more than a century in many parts of the world. Design and composition of the vacuum coffee maker varies. The chamber material is borosilicate glass, metal, or plastic, and the filter can be either a glass rod or a screen made of metal, cloth, paper, or nylon. The Napier Vacuum Machine, presented in 1840, was an early example of this technique. While vacuum coffee makers generally were excessively complex for everyday use, they were prized for producing a clear brew, and were quite popular until the middle of the twentieth century. The Bauhaus interpretation of this device can be seen in Gerhard Marcks' Sintrax coffee maker of 1925.
Before there was the thermometer, there was the earlier and closely related thermoscope, best described as a thermometer without a temperature scale. A thermoscope only showed the differences in temperatures, for example, it could show something was getting hotter. However, the thermoscope did not measure all the data that a thermometer could, for example an exact temperature in degrees. What can be considered the first modern thermometer, the mercury thermometer with a standardized scale, was invented by German-Dutch scientist Daniel Gabriel Fahrenheit (who had settled in Amsterdam in 1701) in 1714. Fahrenheit invented the first truly accurate thermometer using mercury instead of alcohol and water mixtures. He began constructing his own thermometers in 1714, and it was in these that he used mercury for the first time.
The carbon microphone was independently developed around 1878 by David Edward Hughes in England and Emile Berliner and Thomas Edison in the US. Although Edison was awarded the first patent in mid-1877, Hughes had demonstrated his working device in front of many witnesses some years earlier, and most historians credit him with its invention.
Raytheon's research on the magnetron tube revealed the potential of microwaves to cook food. In 1945, Raytheon's Percy Spencer invented the microwave oven by discovering that the magnetron could rapidly heat food. In 1947, the company demonstrated the Radarange microwave oven for commercial use.
The development of the cavity magnetron in the UK made possible the production of electromagnetic waves of a small enough wavelength (microwaves). American engineer Percy Spencer is generally credited with inventing the modern microwave oven after World War II from radar technology developed during the war. Named the "Radarange", it was first sold in 1946. Raytheon later licensed its patents for a home-use microwave oven that was first introduced by Tappan in 1955, but these units were still too large and expensive for general home use. Sharp Corporation introduced the first microwave oven with a turntable between 1964 and 1966. The countertop microwave oven was first introduced in 1967 by the Amana Corporation. After Sharp introduced low-cost microwave ovens affordable for residential use in the late 1970s, their use spread into commercial and residential kitchens around the world. In addition to their use in cooking food, types of microwave ovens are used for heating in many industrial processes.
About 20 years later, John Ambrose Fleming (scientific adviser to the Marconi Company
and former Edison employee) realized that the Edison effect could be used as a radio detector. Fleming patented the first true thermionic diode, the Fleming valve, in Britain on November 16, 1904 (followed by in November 1905).
In 1654, Otto von Guericke invented the first vacuum pump and conducted his famous Magdeburg hemispheres experiment, showing that teams of horses could not separate two hemispheres from which the air had been partially evacuated. Robert Boyle improved Guericke's design and with the help of Robert Hooke further developed vacuum pump technology. Thereafter, research into the partial vacuum lapsed until 1850 when August Toepler invented the Toepler Pump and Heinrich Geissler invented the mercury displacement pump in 1855, achieving a partial vacuum of about 10 Pa (0.1 Torr). A number of electrical properties become observable at this vacuum level, which renewed interest in further research.
An air bag is a safety feature designed to protect automobile passengers in a head-on collision. Most cars today have driver's side airbags and many have one on the passenger side as well. Located in the steering wheel assembly on the driver's side and in the dashboard on the passenger side, the air bag device responds within milliseconds of a crash. The original safety cushion was first created by John W. Hetrick in 1952. After a car accident that his family was involved in, Hetrick drew sketches of compressed air stored in a container. When a spring-loaded weight senses the car decelerating at a rapid enough rate, it opens a valve that allows the pressure in the container to fill a bag. With this knowledge, he developed his design until he was able to obtain a patent on the device on August 5, 1952. Later in 1967, Dr. Allen S. Breed invented and developed a key component for automotive use in 1967, the ball-in-tube inertial sensor for crash detection. Breed Corporation then marketed this innovation to Chrysler.
The development of transistors in 1948 by Bell Laboratories led to major improvements to the hearing aid. The transistor was invented by John Bardeen, Walter Brattain, and William Shockley. Transistors were created to replace vacuum tubes; they were small, required less battery power and had less distortion and heat than their predecessor. These vacuum tubes were typically hot and fragile, so the transistor was the ideal replacement.The 1952 Sonotone 1010 used a transistor stage along with vacuum tubes, to extend battery life. The size of these transistors led to developments in miniature, carbon microphones. These microphones could be mounted on various items, even eyeglasses. In 1951, Raytheon manufactured the transistor and was one of the first companies to mass-produce transistors to throughout America. Raytheon realized that their hearing aid only lasted short-term and began to sell the vacuum-tube hearing aids again along with transistor hearing aids.
The conventional telephone was invented independently by Alexander Bell and Elisha Gray in 1876. Antonio Meucci invented the first device that allowed the electrical transmission of voice over a line in 1849. However Meucci's device was of little practical value because it relied upon the electrophonic effect and thus required users to place the receiver in their mouth to "hear" what was being said. The first commercial telephone services were set-up in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven and London.
The development of thermionic valves starting around 1902, provided an entirely electronic method of amplifying signals. The first practical version of such devices was the Audion triode, invented in 1906 by Lee De Forest, which led to the first amplifiers around 1912. Since the only previous device which was widely used to strengthen a signal was the relay used in telegraph systems, the amplifying vacuum tube was first called an "electron relay". The terms "amplifier" and "amplification", derived from the Latin "amplificare", ("to enlarge or expand"), were first used for this new capability around 1915 when triodes became widespread.
In 1789, Franz Aepinus developed a device with the properties of a "condenser" (now known as a capacitor.) The Aepinus condenser was the first capacitor developed after the Leyden jar, and was used to demonstrate conduction and induction. The device was constructed so that the space between two plates could be adjusted, and the glass dielectric separating the two plates could be removed or replaced with other materials.
The process was invented in Hanau, Germany in 1917. Heraeus Vacuumschmelze and Dr. Wilhelm Rohn applied for a patent on vacuum melting on 12 January 1918 and were granted a German patent DE 345161. E.F. Northrup built the first prototype of a vacuum induction furnace in the United States of America in 1920. Medium frequency furnaces were seen soon afterwards in England and Sweden in 1927. The process was initially developed to refine certain special metals such as cobalt and nickel. As these metals and alloys became more common, the process of VIM became more widely used. VIM now helps to melt a variety of metals for aircraft and nuclear applications.
Polyvinyl chloride (PVC) was discovered by French physicist Henri Victor Regnault, and German physicist Eugen Baumann. Klatte designed the production process, although never successfully commercialised it. Klatte is sometimes incorrectly attributed to be the discoverer or inventor of PVC.
The first carburetor was invented by Samuel Morey in 1826. The first person to patent a carburetor for use in a petroleum engine was Siegfried Marcus with his 6 July 1872 patent for a device which mixes fuel with air.
On 8 May 2012, he appeared on the Radio Four series "The Life Scientific", talking to Jim al-Khalili about the Gaia hypothesis. On the program, he mentioned how his ideas had been received by various people, including Jonathan Porritt. He also mentioned how he had a claim for inventing the microwave oven. He later explained this claim in an interview with "The Manchester Magazine". Lovelock said that he did create an instrument during his time studying causes of damage to living cells and tissue, which had, according to him, "almost everything you would expect in an ordinary microwave oven". He invented the instrument for the purpose of heating up frozen hamsters in a way that caused less suffering to the animals, as opposed to the traditional way which involved putting red hot spoons on the animals' chest to heat them up. He believes that at the time, nobody had gone that far and made an embodiment of an actual microwave oven. However, he does not claim to have been the first person to have the idea of using microwaves for cooking.
After the War, Northrup went to work for Storm Vulcan, a Dallas company, where he invented a machine to clean aircraft engines. He also embarked on a venture to fit cars with air conditioning equipment, putting the machinery in the trunk and piping the cooled air through tubes in the headliner. This caught the interest of engineers from General Motors, who copied the system in Cadillacs in the late 1940s. "After market" automotive AC units were manufactured in Texas until the 1980s. He also sold some of the first air conditioning units, built by the Curtis Mathes Corporation, an early leader in manufacturing window units. Northrup married Jane Keliher and started a family in Dallas, where he designed and built one of the first single-family houses in the United States with central air conditioning. He founded a company to install air conditioning in residential and commercial buildings. With a Marketing Plan from G F Sweetman (CEO of American Awards Co), he became one of largest suppliers of Curtis Mathes fans and compressors in the nation. He also developed a company to manage, install, update, and clean air filtration systems.
In 1945, Robert Sherman of Lynn, Massachusetts invented a portable, in-window air conditioner that cooled, heated, humidified, dehumidified, and filtered the air.
Designed to improve manufacturing process control in a printing plant, Carrier's invention controlled not only temperature but also humidity. Carrier used his knowledge of the heating of objects with steam and reversed the process. Instead of sending air through hot coils, he sent it through cold coils (filled with cold water). The air was cooled, and thereby the amount of moisture in the air could be controlled, which in turn made the humidity in the room controllable. The controlled temperature and humidity helped maintain consistent paper dimensions and ink alignment. Later, Carrier's technology was applied to increase productivity in the workplace, and The Carrier Air Conditioning Company of America was formed to meet rising demand. Over time, air conditioning came to be used to improve comfort in homes and automobiles as well. Residential sales expanded dramatically in the 1950s.
The 2nd-century Chinese mechanical engineer and inventor Ding Huan of the Han Dynasty invented a rotary fan for air conditioning, with seven wheels in diameter and manually powered by prisoners of the time. In 747, Emperor Xuanzong (r. 712–762) of the Tang Dynasty (618–907) had the "Cool Hall" ("Liang Dian" ) built in the imperial palace, which the "Tang Yulin" describes as having water-powered fan wheels for air conditioning as well as rising jet streams of water from fountains. During the subsequent Song Dynasty (960–1279), written sources mentioned the air conditioning rotary fan as even more widely used.