| 摘要 |
A method for printing viscous material, such as solder paste, onto a surface of a board, such as a printed circuit board, through a screen having openings therein. The method includes feeding the material into a chamber of a dispenser, dispensing the material contained in the chamber onto an upper surface of the screen and onto the surface of the board from the dispenser through a slit-like bottom aperture therein and through a space between a pair of blades including a leading blade and a trailing balde and depending from the dispenser on opposite sides of the bottom aperture to contact the upper surface of the screen, the dispenser having a rear wall comprising a fixed upper wall section and a height adjustable lower wall section connected thereto, the trailing blade serving as a squeegee blade and fixed to the height-adjustable lower wall section, moving the dispenser in a direction of travel thereof so that the squeegee blade urges the material dispensed from the dispenser through openings if the screen and onto the surface of the board, and adjusting the contacting pressure of the lower end of the squeegee blade to be applied against the upper surface of the screen by causing the the squeegee blade to be raised or lowered by means of manually operable height-adjustable means mounted on the dispenser and operatively connected to the height-adjustable lower wall section for raising and lowering the lower wall section with the squeegee blade within a predetermined range of height.
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