Multi-cylinder rotary compressor

A multi-cylinder rotary compressor for accommodating an electric element and a rotary compression element in a closed container,

• said rotary compression element comprising:
• an intermediate partition plate;
• a second cylinder provided on said electric element side of said intermediate partition plate;
• a first cylinder provided on the opposite side of said intermediate partition plate;
• a rotating shaft which has eccentric element portions whose rotating angles are shifted from each other 180 degrees and is connected to said electric element;
• rollers which are fitted to said respective eccentric portions of said rotating shaft and rotate in said respective cylinders;
• and bearing for closing openings of said respective cylinders;
• said electric element comprising:
• a stator, and a rotator which is supported by said rotating shaft and rotatable on the inner side of said stator, and a balancer connected to said rotator;
• wherein the mass eccentricity in said first cylinder is m1×r1 and the mass eccentricity in said second cylinder is m2×r2;
• and
• wherein assuming:
• (a) the mass eccentricity of a first balancer portion attached to one end of said rotator positioned on the side of said rotary compression element is m3×r3;
• (b) the mass eccentricity of a second balancer portion attached to the other end of said rotator is m4×r4;
• (c) respective distances from said first cylinder to said second cylinder, said first balancer and said second balancer are L2, L3 and L4;
• and (d) balancing is attained with the following expressions:
• m1×r1+m4×r4=m2×r2+m3×r3
• m4×r4×L4=m2×r2×L2+m3×r3×L3
• m1×r1=m2×r2,
• then said balancer has said first balancer portion eliminated and the mass eccentricity of said second balancer portion is set to be not less than about 20% and not more than about 80% of m4×r4.