Decoupler as one-way clutch

A decoupler, comprising:

• a pulley around which a belt is wound;
• a sprag limiter fixed to an interior circumference of the pulley and having protrusions formed at predetermined intervals in a circumferential direction on an interior circumference thereof;
• a sprag hub disposed in the sprag limiter and having first apertures formed at predetermined intervals in the circumferential direction from an interior circumference thereof to an exterior circumference thereof;
• a shaft hub disposed in the sprag hub and having second apertures formed at positions each corresponding to the first apertures from an interior circumference thereof to an exterior circumference thereof;
• a plurality of sprags having lower end portions each inserted into the second apertures, central portions each inserted into the first apertures, and upper end portions formed to be in contact with the interior circumference of the sprag limiter, and allowing the shaft hub to rotate in one direction based on movement of the pulley;
• and
• a plurality of fins that fix each of the sprags to the sprag hub by penetrating between the interior circumference and the exterior circumference of the sprag hub in an axial direction to correspond to positions of the first apertures.