A linear compressor is a
gas compressor
A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor.
Compressors are similar to pumps: both increase the pressure on a fluid and both can tra ...
where the piston moves along a linear track to minimize friction and reduce energy loss during conversion of motion. This technology has been successfully used in cryogenic applications which must be oilless. Suspension spring can be flexure type or coil type. Oil-free valved linear compressor allows the use of compact heat exchangers.
Linear compressors work similarly to a
solenoid
upright=1.20, An illustration of a solenoid
upright=1.20, Magnetic field created by a seven-loop solenoid (cross-sectional view) described using field lines
A solenoid () is a type of electromagnet formed by a helix, helical coil of wire whose ...
: by using a spring-loaded piston with an electromagnet connected to AC through a diode. The spring-loaded piston is the only moving part, and it is placed in the center of the electromagnet. During the positive cycle of the AC, the diode allows energy to pass through the electromagnet, generating a magnetic field that moves the piston backwards, compressing the spring, and generating suction. During the negative cycle of the AC, the diode blocks current flow to the electromagnet, letting the spring uncompress, moving the piston forward, and compressing the refrigerant. The compressed refrigerant is then released by a valve.
History
A number of patents for linear compressors powered by
free-piston engines were issued in the 20th century, including:
* To
Brown, Boveri & Cie
Brown, Boveri & Cie. (Brown, Boveri & Company; BBC) was a Swiss group of electrical engineering companies.
It was founded in Zürich, in 1891 by Charles Eugene Lancelot Brown and Walter Boveri who worked at the Maschinenfabrik Oerlikon. In ...
, GB191215963, published 1913-10-08
* To
Hugo Junkers, CA245708, published 1924-12-30
* To
Raúl Pateras Pescara, US1615133, published 1927-01-18
The first market introduction of a linear compressor to compress
refrigerant
A refrigerant is a working fluid used in the refrigeration cycle of air conditioning systems and heat pumps where in most cases they undergo a repeated phase transition from a liquid to a gas and back again. Refrigerants are heavily regulate ...
in a
refrigerator was in 2001.
Valved linear compressor
The single piston linear compressor uses dynamic counterbalancing, where an auxiliary movable mass is flexibly attached to a movable piston assembly and to the stationary compressor casing using auxiliary mechanical springs with zero vibration export at minimum electrical power and current consumed by the motor.
It is used in
cryogenic
In physics, cryogenics is the production and behaviour of materials at very low temperatures.
The 13th IIR International Congress of Refrigeration (held in Washington DC in 1971) endorsed a universal definition of “cryogenics” and “cr ...
s.
Linear compressors are used in LG and Kenmore refrigerators. Compressors of this type have less noise, and are more energy efficient than conventional refrigerator compressors.
See also
*
*
*
*
*
*
Scroll compressor
References
External links
*
{{HVAC
Gas compressors
Vacuum pumps
Cooling technology
Hydrogen technologies