Coupler may refer to:

Engineering

Mechanical

* Railway coupler, a mechanism for connecting rolling stock on a train **

Janney coupler Knuckle 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. Originally known as Janney couplers (the original patent n ...

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 (, 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 has gradually spread from tr ...

for multiple unit passenger cars * Quick coupler, 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 mo ...

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

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

Output coupler In laser science, 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, al ...

, a partially reflective mirror used in lasers *

Optocoupler An opto-isolator (also called an optocoupler, photocoupler, or optical isolator) is an electronic component that transfers electrical Signal, signals between two isolated circuits by using light. Opto-isolators prevent high voltages from affecti ...

, an electronic component that transfers electrical signals between two isolated circuits by using light

Other uses

* Coupler (piping), 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 pressurised air (called ''wind'') through the organ pipes selected from a Musical keyboard, keyboard. Because each pipe produces a single tone and pitch, the pipes are provide ...

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 Mechanism (engineering), mechanisms, a four-bar linkage, also called a four-bar, is the simplest closed-Kinematic chain, chain movable linkage (mechanical), linkage. It consists of four Rigid body, bodies, called ''bars'' or ''link ...

* Hydrant coupler, for aircraft fueling equipment

Engineering

Mechanical

Electronics

Other uses

See also