Multicylindrical rotary compressor, compression system, and freezing device using the compression system

A compression system comprising:

• a multicylindrical rotary compressor provided with a sealed container in which a driving element and first and second rotary compression elements driven by a rotation shaft of the driving element are contained, the first and second rotary compression elements including:
• first and second cylinders;
• first and second rollers engaged with eccentric portions formed on the rotation shaft to rotate eccentrically in the respective chambers, respectively;
• and first and second vanes which abut on the first and second rollers to divide each cylinder into a low-pressure chamber side and a high-pressure chamber side, the compressor being constituted to be usable by urging the only first vane with respect to the first roller by means of a spring member to switch a first operation mode in which both of the rotary compression elements perform compression works and a second operation mode in which substantially the only first compression element performs the compression work,
• wherein an oil of an oil reservoir in the sealed container is supplied to a back-pressure chamber of the second vane in the first operation mode, and
• a suction-side pressure of the first rotary compression element is applied to the back-pressure chamber of the second vane in the second operation mode.