AUTOMATIC FLAT BED SCREEN PRINTING MACHINE
This method of printing the manual flat-bed screen printing process is improved by mechanisation.
MECHANISM AND PROCEDURE:
The machine consists of a printing table (flat bed), conveyor belt to bring fabric on to table under the screens, a mechanism for lowering the screen on the required areas of the fabric, squeegees driven by motor, a conveyor under the table to collect extra paste, and arrangement for gumming the fabric to the conveyor belt and a drier. Number of screens is equal to the number of colours in the design. Screens are arranged one beside the other in the order of colour tobe printed from first to last.
When printing, the fabric is brought on to printing table through a feeding arrangement and gummed to the conveyor belt on the table. The gumming is done by a padder, which has the bottom rotation in a gum box and transmits the gum to the top shaft, thus transferring gum to conveyor belt. The conveyor brings fabric periodically under the screens and stops while the screens are lowered on the fabric at required areas the squeegees make one or more strokes over the screen after which the screens are lifted again and fabric is moved on.
Printing paste prepared in tanks is brought through flexible hoses and poured on the screen. It is then distributed throughout the length of the screen. The squeegee is pressed on the screen by dynamo-meter placed at both ends of the squeegee holders. One or more strokes of the squeegee ensure simultaneous printing of the pattern by common action on all screens, each of which applies the printing paste as required by the colours in the designs. Excess paste is collected by a special conveyor running under the table. After printing the fabric is dried by passing through a hot air chamber. The conveyor returns to its original position where it is washed, dried and a new fabric length is gummed on.