Abstract: A compressor includes a cylinder, and a rotary rod arranged in the cylinder. A spiral groove is formed on the outer periphery of the rotary rod. The spiral groove is formed such that its depth direction extending from the bottom of the groove to the opening thereof is inclined at a predetermined angle toward a discharge side of the cylinder with respect to the axis of the rotary rod. Pitches of the spiral groove are gradually narrowed with distance from the suction-side end of the cylinder. A spiral blade is fitted in the spiral groove to be slidable in the depth direction. The blade divides a space between the outer periphery of the rotary rod and the inner surface of the cylinder into a plurality of working chambers. When the cylinder and rotary rod are relatively rotated, a fluid, introduced into the suction-side end of the cylinder, is transported toward the discharge-side end of the cylinder through the working chambers.