HOME





Constant Speed Drive
A constant speed drive (CSD) also known as a constant speed generator, is a type of transmission that takes an input shaft rotating at a wide range of speeds, delivering this power to an output shaft that rotates at a constant speed, despite the varying input. They are used to drive mechanisms, typically electrical generators, that require a constant input speed. The term is most commonly applied to hydraulic transmissions found in the accessory drives of gas turbine engines, such as aircraft jet engines. On modern aircraft, the CSD is often combined with a generator into a single unit known as an integrated drive generator (IDG). Mechanism CSDs are mainly used on airliner and military aircraft jet engines to drive the alternating current (AC) electrical generator. In order to produce the proper voltage at a constant AC frequency, usually three-phase 115 VAC at 400 Hz, an alternator needs to spin at a constant specific speed (typically 6,000 RPM for air-cooled generators ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Constant Speed Drive For Boeing 727, Sundstrand Corporation - Museum Of Science And Industry (Chicago) - DSC06323
Constant or The Constant may refer to: Mathematics * Constant (mathematics), a non-varying value * Mathematical constant, a special number that arises naturally in mathematics, such as pi, or Other concepts * Control variable or scientific constant, in experimentation the unchanging or constant variable * Physical constant, a physical quantity generally believed to be universal and unchanging * Constant (computer programming), a value that, unlike a variable, cannot be reassociated with a different value * Logical constant, a symbol in symbolic logic that has the same meaning in all models, such as the symbol "=" for "equals" People * Constant (given name) * Constant (surname) * John, Elector of Saxony (1468–1532), known as John the Constant * Constant Nieuwenhuys (1920-2005), better known as Constant Places * Constant, Barbados, a populated place Arts and entertainment

* "The Constant", a 2008 episode of the television show ''Lost'' * The Constant (Story of the Year a ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Airbus A340
The Airbus A340 is a long-haul, long-range, wide-body passenger airliner that was developed and produced by Airbus. In the mid-1970s, Airbus conceived several derivatives of the Airbus A300, A300, its first airliner, and developed the A340 quadjet in parallel with the Airbus A330, A330 twinjet. In June 1987, Airbus launched both designs with their first orders and the A340-300 took its maiden flight on 25 October 1991. It was certified along with the A340-200 on 22 December 1992 and both versions entered service in March 1993 with launch customers Lufthansa and Air France. The larger A340-500/600 were launched on 8 December 1997; the A340-600 flew for the first time on 23 April 2001 and entered service on 1 August 2002. Keeping the eight-abreast economy cross-section of the A300, the early A340-200/300 has a similar airframe to the A330-200/300. Differences include four CFM56s instead of two high-thrust turbofans to bypass ETOPS restrictions on trans-oceanic routes, and a th ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Centrifugal Governor
A centrifugal governor is a specific type of governor with a feedback system that controls the speed of an engine by regulating the flow of fuel or working fluid, so as to maintain a near-constant speed. It uses the principle of proportional control. Centrifugal governors, also known as "centrifugal regulators" and "fly-ball governors", were invented by Christiaan Huygens and used to regulate the distance and pressure between millstones in windmills in the 17th century. In 1788, James Watt adapted one to control his steam engine where it regulates the admission of steam into the cylinder(s), a development that proved so important he is sometimes called the inventor. Centrifugal governors' widest use was on steam engines during the Steam Age in the 19th century. They are also found on stationary internal combustion engines and variously fueled turbines, and in some modern striking clocks. A simple governor does not maintain an exact speed but a speed range, since under increa ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Permanent Magnet Synchronous Generator
A permanent magnet synchronous generator is a generator where the excitation field is provided by a permanent magnet instead of a coil. The term ''synchronous'' refers here to the fact that the rotor and magnetic field rotate with the same speed, because the magnetic field is generated through a shaft-mounted permanent magnet mechanism, and current is induced into the stationary armature. Description Synchronous generators are the majority source of commercial electrical energy. They are commonly used to convert the mechanical power output of steam turbines, gas turbines, reciprocating engines, and hydro turbines into electrical power for the grid. Some designs of wind turbines also use this generator type. In the majority of designs, the rotating assembly in the center of the generator—the ''rotor''—contains the magnet, and the ''stator'' is the stationary armature that is electrically connected to a load. As shown in the diagram, the perpendicular component of the stato ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Power Inverter
A power inverter, inverter, or invertor is a power electronic device or circuitry that changes direct current (DC) to alternating current (AC). The resulting AC frequency obtained depends on the particular device employed. Inverters do the opposite of rectifiers which were originally large electromechanical devices converting AC to DC. The input voltage, output voltage and frequency, and overall power handling depend on the design of the specific device or circuitry. The inverter does not produce any power; the power is provided by the DC source. A power inverter can be entirely electronic or maybe a combination of mechanical effects (such as a rotary apparatus) and electronic circuitry. Static inverters do not use moving parts in the conversion process. Power inverters are primarily used in electrical power applications where high currents and voltages are present; circuits that perform the same function for electronic signals, which usually have very low currents and vol ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Tap Converter
The tap converter is a variation on the cycloconverter, invented in 1981 by New York City electrical engineer Melvin Sandler and significantly functionally enhanced in 1982 through 1984 by graduate students Mariusz Wrzesniewski, Bruce David Wilner, and Eddie Fung. Whereas the cycloconverter switches among a variety of staggered input phases to piece together an extremely jagged output signal, the tap converter synthesizes a much smoother signal by switching among a variety of (obviously synchronized) transformer output taps. Tap positions Both linear spacing and power-of-two-style Vernier spacing can be employed in establishing the tap positions, ''e.g.'', a four-tap transformer can provide taps at 0.25, 0.5, 0.75, 1.0 (linear) or 0.0625, 0.125, 0.25, and 0.5 (Vernier). (The limitations of the Vernier—in this case, that the maximum obtainable amplitude is 0.9375—are less discernible as more taps are added.) Scott transformer By employing a Scott transformer input conn ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Hamilton Sundstrand
Hamilton Sundstrand was an American globally active corporation that manufactured and supported aerospace and industrial products for worldwide markets. A subsidiary of United Technologies Corporation, it was headquartered in Windsor Locks, Connecticut. The company was formed from the merger of Hamilton Standard and Sundstrand Corporation in 1999. In 2012, Hamilton Sundstrand was merged with Goodrich Corporation to form UTC Aerospace Systems. In 2018, UTC Aerospace Systems and Rockwell Collins combined to form Collins Aerospace. History On June 10, 1999, Hamilton Standard and the Sundstrand Corp. were merged, forming Hamilton Sundstrand. Hamilton Sundstrand traces its roots to the founding of the Sundstrand Corp. in 1905 and Hamilton Standard in 1910. In early 2001, Claverham Ltd was sold to Hamilton Sundstrand. On 2 January 2008, Hamilton Sundstrand said it would commercialize the concentrated solar power tower technology and corresponding molten salt storage system develop ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Collins Aerospace
Collins Aerospace is an American technology company that is one of the world's largest suppliers of aerospace and defense products. It was formed in 2018 from the merger of Rockwell Collins and UTC Aerospace Systems. Headquartered in Charlotte, North Carolina, it is a subsidiary of RTX Corporation. History On November 26, 2018, United Technologies announced the completion of its Rockwell Collins acquisition, after which it merged its newly acquired business with UTC Aerospace Systems to form Collins Aerospace. This acquisition controversially led to multiple class action lawsuits being filed against the company alleging that the executives deliberately misled its shareholders on the nature of the acquisition. The new company reported $26 billion of combined sales in 2019 and is composed of 68,000 employees. In 2020 United Technologies merged with Raytheon Company to form Raytheon Technologies, which has since renamed itself to RTX Corporation. In July 2023, Collins agreed ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Line-replaceable Unit
A line-replaceable unit (LRU), lower line-replaceable unit (LLRU), line-replaceable component (LRC), or line-replaceable item (LRI) is a modular component of an airplane, ship or spacecraft (or any other manufactured device) that is designed to be replaced quickly at an operating location (1st line). The different lines (distances) are essential for logistics planning and operation. An LRU is usually a sealed unit such as a radio or other auxiliary equipment. LRUs are typically assigned logistics control numbers (LCNs) or work unit codes (WUCs) to manage logistics operations. LRUs can improve maintenance operations, because they can be stocked and replaced quickly from distributed nearby on-site inventories (sometimes mobile storage), restoring the mobile systems to service, while the failed (unserviceable) LRU is undergoing complicated repair and overhaul actions in other support locations (lines). Because of their modularity, LRUs also can contribute reducing system costs and i ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

United Technologies Corporation
United Technologies Corporation (UTC) was an American multinational corporation, multinational list of conglomerates, conglomerate headquartered in Farmington, Connecticut. It researched, developed, and manufactured products in numerous areas, including aircraft engines, aerospace systems, HVAC, elevators and escalators, fire and security, building automation, and industrial products, among others. UTC was also a large military contractor, getting about 10% of its revenue from the U.S. government. In April 2020, UTC merged with the Raytheon Company to form Raytheon Technologies, later renamed RTX Corporation. History Pre-1970s 1970s and 1980s In 1974, Harry Jack Gray left Litton Industries to become the CEO of United Aircraft.. He pursued a strategy of growth and diversification, changing the parent corporation's name to United Technologies Corporation (UTC) in 1975 to reflect the intent to diversify into numerous high tech fields beyond aerospace.. (The change became off ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Boeing 777
The Boeing 777, commonly referred to as the Triple Seven, is an American long-range wide-body airliner developed and manufactured by Boeing Commercial Airplanes. The 777 is the world's largest twinjet and the most-built wide-body airliner. The jetliner was designed to bridge the gap between Boeing's other wide body airplanes, the twin-engined 767 and quad-engined 747, and to replace aging DC-10 and L-1011 trijets. Developed in consultation with eight major airlines, the 777 program was launched in October 1990, with an order from United Airlines. The prototype aircraft rolled out in April 1994, and first flew that June. The 777 entered service with the launch operator United Airlines in June 1995. Longer-range variants were launched in 2000, and first delivered in 2004. The Triple Seven can accommodate a ten–abreast seating layout and has a typical 3-class capacity of 301 to 368 passengers, with a range of . The jetliner is recognizable for its large-diameter tur ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Boeing 767
The Boeing 767 is an American wide-body airliner developed and manufactured by Boeing Commercial Airplanes. The aircraft was launched as the 7X7 program on July 14, 1978, the prototype first flew on September 26, 1981, and it was certified on July 30, 1982. The initial 767-200 variant entered service on September 8, 1982, with United Airlines, and the extended-range 767-200ER in 1984. It was stretched into the in October 1986, followed by the extended-range 767-300ER in 1988, the most popular variant. The 767-300F, a production freighter version, debuted in October 1995. It was stretched again into the 767-400ER from September 2000. Designed to complement the larger 747, it has a seven-abreast cross-section accommodating smaller LD2 ULD cargo containers. The 767 is Boeing's first wide-body twinjet, powered by General Electric CF6, Rolls-Royce RB211, or Pratt & Whitney JT9D turbofans. JT9D engines were eventually replaced by PW4000 engines. The aircraft has a conven ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]