Multi-stage compressor and method of controlling the same

A multi-stage compressor comprising:

• a compression module configured to compress a refrigerant therein through reciprocation of a plurality of pistons provided in a front housing;
• a rear housing coupled to the front housing to define an internal space between the front housing and the rear housing;
• a separation plate located between the front housing and the rear housing to separate the internal space between the front housing and the rear housing into a front space and a rear space;
• and
• a partition wall coupled to the rear housing to partition the rear space into an injection space before the refrigerant injected thereinto is primarily compressed, a primary discharge space from which the refrigerant is discharged in a primary compressed state by some of the pistons, and a secondary discharge space from which the primary compressed refrigerant is discharged in a secondary compressed state by some of the pistons, wherein the partition wall further comprises an integral partition wall coupled integrally with the rear housing, and a fluidized partition wall rotatably coupled to the rear housing to vary the number of cylinders of each piston used for the primary compression and the secondary compression.

A multi-stage compressor comprising:

• a compression module configured to compress a refrigerant therein through reciprocation of a plurality of pistons provided in a front housing;
• a rear housing coupled to the front housing to define an internal space between the front housing and the rear housing;
• a separation plate located between the front housing and the rear housing to separate the internal space between the front housing and the rear housing into a front space and a rear space, wherein the separation plate is formed with a plurality of inlets and outlets for introducing the refrigerant in the rear space into the front space or for discharging the refrigerant in the front space to the rear space;
• and
• a partition wall coupled to the rear housing to partition the rear space into an injection space before the refrigerant injected thereinto is primarily compressed, a primary discharge space from which the refrigerant is discharged in a primary compressed state by some of the pistons, and a secondary discharge space from which the primary compressed refrigerant is discharged in a secondary compressed state by some of the pistons, wherein the partition wall further comprises an integral partition wall coupled integrally with the rear housing, and a fluidized partition wall rotatably coupled to the rear housing to vary the number of cylinders of each piston used for the primary compression and the secondary compression.