Patent ID: 6131511
Filing Date: 2000-10-17
Classification: B41F,H05K,Y10S

Abstract:
A screen printing method comprising:positioning a circuit board in a loading position on a stage of a screen printing apparatus such that the circuit board does not overlap with a screen of the screen printing apparatus;recognizing a set position of the screen relative to a recognition reference point by arbitrarily detecting two different points on the screen and by calculating positions of the two points on the screen relative to the recognition reference point when the screen is set;recognizing a placement position of the circuit board relative to the recognition reference point by detecting two different lands on the circuit board corresponding to the two points on the screen and by calculating positions of the two lands on the circuit board relative to the recognition reference point when the circuit board is placed on the stage;calculating a correction amount for repositioning at least one of the screen and the circuit board based on the set position recognized for the screen and the placement position recognized for the circuit board;moving at least one of the stage and the screen such that the screen and the circuit board are overlaid, said moving of at least one of the stage and the screen being based on the correction amount each time a circuit board of a same type is positioned on the stage;providing solder paste on the screen; andprinting the solder paste from the screen onto the circuit board overlaid with the screen.