Patent ID: 7988430

Claim:
A linear compressor, comprising: a main body frame provided in a hermetic space formed within a shell; a cylinder that is sintering molded, the cylinder including: a cylinder main body; a flange that protrudes outward from an outer circumferential surface of the cylinder main body so as to be supported by the main body frame; and a rotation restriction member provided on the outer circumferential surface of the cylinder main body, wherein the rotation restriction member comprises at least one linear flat surface extending along an outer circumferential surface of the flange, wherein the at least one linear flat surface contacts the main body frame so as to prevent the cylinder from rotating relative to the main body frame; a piston that reciprocates within the cylinder so as to compress refrigerant flowing into the cylinder; and a linear motor, positioned at an outer circumference of the cylinder so as to drive the piston, wherein the linear motor includes: a ring shaped inner stator positioned at the outer circumferential surface of the cylinder, wherein the rotation restriction member prevents rotation of the cylinder against the inner stator or prevents rotation of the flange against the main body frame; a ring shaped outer stator positioned outside the inner stator; and a permanent magnet positioned between the inner and outer stator and connected to the piston.