Coupler may refer to:

Engineering

Mechanical

Railway coupler A coupling (or a coupler) is a mechanism typically placed at each end of a railway vehicle that connects them together to form a train. A variety of coupler types have been developed over the course of railway history. Key issues in their desig ...

, a mechanism for connecting rolling stock in a train device **

Janney coupler Janney couplers are a semi-automatic form of railway coupling that allow rail cars and locomotives to be securely linked together without rail workers having to get between the vehicles. They are also known as American, AAR, APT, ARA, MCB, knuck ...

SA3 coupler SA3 couplers (also known as СА3 or СА-3 couplers per the typical foundry stamp on top of these couplers, meaning "Советская Автосцепка, 3" in Russian or "Soviet Auto-latch 3" in English) or Willison coupler and Russia ...

Scharfenberg coupler The Scharfenberg coupler (german: Scharfenbergkupplung, abbreviated ''Schaku'') is a commonly used type of fully automatic railway coupling. Designed in 1903 by Karl Scharfenberg in Königsberg, Germany (today Kaliningrad, Russia), the coupler ...

for multiple unit passenger cars *

Quick coupler Quick couplers (also called quick hitches) are used with construction machines to allow the rapid change of buckets and attachments on the machine. They remove the need to use hammers to manually drive out and insert the mounting pins for attach ...

, used in construction machines to allow the rapid change of buckets *

Coupling A coupling is a device used to connect two shafts together at their ends for the purpose of transmitting power. The primary purpose of couplings is to join two pieces of rotating equipment while permitting some degree of misalignment or end mov ...

, a device used to connect two shafts together at their ends for the purpose of transmitting power **

Universal coupling A universal joint (also called a universal coupling or U-joint) is a joint or coupling connecting rigid shafts whose axes are inclined to each other. It is commonly used in shafts that transmit rotary motion. It consists of a pair of hinges lo ...

, a joint or coupling in a rigid rod that allows the rod to 'bend' in any direction

Electronics

Acoustic coupler In telecommunications, an acoustic coupler is an interface device for coupling electrical signals by acoustical means—usually into and out of a telephone. The link is achieved through converting electric signals from the phone line to sound a ...

, for coupling electrical signals by acoustical means *

Directional coupler Power dividers (also power splitters and, when used in reverse, power combiners) and directional couplers are passive devices used mostly in the field of radio technology. They couple a defined amount of the electromagnetic power in a transmiss ...

, a passive device used in radio technology *

Antenna coupler An antenna tuner (and any of the names in the list below) is a device that is inserted between a radio transmitter and its antenna; when placed close by the antenna and properly adjusted (tuned) it optimizes power transfer by matching the im ...

, a device connected between a radio transmitter or receiver and its antenna *

Output coupler An output coupler (OC) is the component of an optical resonator that allows the extraction of a portion of the light from the laser's intracavity beam. An output coupler most often consists of a partially reflective mirror, allowing a certain por ...

, a partially reflective mirror used in lasers

Other uses

Coupler (piping) In piping and plumbing, a coupling (or coupler) is a very short length of pipe or tube, with a socket at one or both ends that allows two pipes or tubes to be joined, welded ( steel), brazed or soldered (copper, brass etc.) together. Alternati ...

, also called a (joist) short length of pipe with two female threads * Coupler, a device used on a

pipe organ The pipe organ is a musical instrument that produces sound by driving pressurized air (called ''wind'') through the organ pipes selected from a keyboard. Because each pipe produces a single pitch, the pipes are provided in sets called ''ranks ...

or harpsichord to allow a player to play multiple divisions at once, by means of "coupling" a division to another at either sub, super, or octave pitches * Coupler, a tap valve, for controlling the release of beer out of a keg * Coupler, the floating link in a

four-bar linkage In the study of mechanisms, a four-bar linkage, also called a four-bar, is the simplest closed- chain movable linkage. It consists of four bodies, called ''bars'' or ''links'', connected in a loop by four joints. Generally, the joints are configu ...

Hydrant coupler A hydrant coupler is a type of aircraft fueling equipment which opens and allows fuel to flow through the hydrant cart into the aircraft. A hydrant coupler needs 60lbs of air pressure to open up the Valve, pit valve to allow the flow of fuel. Hydra ...

, for aircraft fueling equipment

Engineering

Mechanical

Electronics

Other uses

See also