Double-headed piston type compressor

A double-headed piston type compressor comprising:

• a drive shaft;
• a housing that rotatably supports the drive shaft and has m first cylinder bores, where m is an integer satisfying m≧2, at one side of the drive shaft and m second cylinder bores facing the respective first cylinder bores at the other side of the drive shaft;
• m double-headed pistons that reciprocate in the respective first and second cylinder bores by rotation of the drive shaft;
• a first discharge chamber that is formed into an annular shape in the housing and into which refrigerant compressed in the first cylinder bores is discharged;
• a second discharge chamber that is formed into an annular shape in the housing and into which refrigerant compressed in the second cylinder bores is discharged;
• a merging portion in which the refrigerant discharged into the first discharge chamber and the refrigerant discharged into the second discharge chamber merge together, the merging portion being capable of discharging the merged refrigerant to the outside;
• at least one first discharge passage that provides communication between the first discharge chamber and the merging portion;
• and
• at least one second discharge passage that provides communication between the second discharge chamber and the merging portion,
• wherein the first discharge chamber is divided into m first discharge sections that correspond to the respective first cylinder bores,
• the second discharge chamber is divided into m second discharge sections that correspond to the respective second cylinder bores,
• n out of the first discharge sections, where n is an arbitrary integer satisfying 1≦n<m, are defined as specified first discharge sections,
• n out of the second discharge sections are defined as specified second discharge sections,
• when viewed from an axial direction of the drive shaft, at least one of the specified first discharge sections and at least one of the specified second discharge sections are disposed at positions shifted from each other,
• the at least one first discharge passage is n in number and each communicates with each of the specified first discharge sections and the merging portion, and
• the at least one second discharge passage is n in number and each communicates with each of the specified second discharge sections and the merging portion.