Screen printing apparatus having paste chamber with discharge opening and structure for introducing paste residue from previous printing into discharge opening

A screen printing apparatus having a housing-like main body that is long sideways, characterized in that inside the main body, there are provided a paste accommodation chamber and a roller pivotally mounted along the axis of the main body so as to be capable of being rotated in normal and reverse directions,

• that a discharge opening that is long sideways and serves to discharge a paste accommodated in the paste accommodation chamber onto the upper surface of a screen placed on a printed circuit board is formed at the bottom of the main body between a scraper that projects forward and diagonally downward and whose tip slides on the screen upper surface during printing while being in contact therewith and a guide plate that is opposed to the scraper and projects backward and diagonally downward and whose tip ends at a height where a predetermined gap is maintained from the tip to the screen upper surface during printing, so that as the main body is moved forward, that is, in a printing direction and the roller is rotated in the normal direction, the paste can be filled in pattern holes of the screen by fluid pressure of the paste discharged from the discharge opening,
• that a front wall of the main body is formed with a space for introducing a residue of the paste adhered to the screen upper surface in the preceding printing to the discharge opening through said gap in each printing, so that the paste residue is mixed into the paste discharged from the discharge opening can be used for printing, and that as the roller is rotated in the reverse direction at the end of a printing operation, the paste remaining in the vicinity of the discharge opening is introduced and collected into the paste accommodation chamber.