Method for mounting parts

1. A method for mounting parts comprising the steps of:

recognizing a particular part feeder where a part to be mounted is contained among a plurality of part feeders;

moving a head unit to a position for picking up a part on the part feeder;

moving an image sensor installed to be capable of moving to a position close to the particular part feeder;

picking up a part from the particular part feeder with a suction nozzle installed at the head unit;

moving the head unit to a position above the image sensor;

detecting an image of the part held by the suction nozzle;

moving the suction nozzle to a printed circuit board from the image sensor; and

aligning the part with the printed circuit board while determining and compensating for an error generated when the part is picked up, and mounting the aligned part on the printed circuit board,

wherein the determining and compensating is performed by the steps of:

determining the coordinates of the center of the suction nozzle by detecting a position of a reference portion which is not covered by the part when the image is obtained;

determining the coordinates of the center of the part from an image obtained by the image sensor;

calculating a value of correction of the part position by determining an offset of the part from the displacement of the center of the part held by the suction nozzle from the center of the suction nozzle; and

controlling a position for mounting the part with the suction nozzle according to the value of the correction.