What is a Scroll Compressor?
A scroll compressor is a form of air compressor first invented in 1905. Despite its age, the scroll compressor is still commonly used in air conditioning systems, central heating pumps, and automotive air conditioners. The same design is incorporated into vehicle superchargers where it's more commonly known as a scroll-type supercharger. Unlike traditional piston-powered air compressors, scroll compressors run more smoothly and are far more energy-efficient thanks to the process by which they compress air.
The basis of the scroll compressor is an air-tight chamber shaped like a drum or cylinder. Within this chamber are two spirals made of metal, interlocking with one another. One of the spirals is static; it's welded into place and does not move. The other is situated on top of a reciprocating armature connecting the to the pump's motor. The air intake valve is situated on the base of the drum's exterior, where the outermost edges of the spirals converge. The output valve is located at the top of the drum where the centers of the spirals meet.
How Does a Scroll Compressor Work?
The motor starts the armature moving, causing the spiral to move in a set circular motion. Note that the spiral does not rotate, but the entire thing moves in a constant circle. As the spiral moves, it generates suction as it presses against the sides of the static spiral. These pockets progress from the air intake inward, around and around the bodies of the two spirals, compressing all the while as they move toward the center of the drum. Once they reach the center of the two spirals, the air is compressed and forced through the output valve by the continuous motion. Some scroll compressors have a storage chamber connected to the output valve into which the air is placed, where others connect directly to air-tight hoses through which the compressed air is pumped.