Flatbed printing machine
View Patent ↗A flatbed printing machine is provided with a printing table and a pressing device for a medium to be printed. The pressing device features parallel guide rails on both sides of the printing table, through which a pressing rail that is moveable above the printing table is guided. The pressing device is particularly applicable to a digital ink-jet flatbed printing machines.
1. A flatbed printing machine with a printing table, the flatbed printing machine comprising:
a pressing device arranged to press a medium against the printing table, the pressing device including:
first and second guide rails arranged parallel or substantially parallel to and on both sides of the printing table;
first and second guide carriages arranged to run on the first and second guide rails, respectively;
a traversing device arranged to traverse the first and second guide carriages along the first and second guide rails;
a pressing rail pivotally connected to the first and second guide carriages, the pressing rail including one of a brush and a roller; and
a lifting device arranged to lower and lift the pressing rail; wherein
the one of a brush and a roller is arranged to press the medium against the printing table as the first and second guide carriages traverse the pressing rail across the printing table while the pressing rail is in a lowered position thereby sweeping the one of a brush and a roller across the medium to smooth out any creases in the medium and remove air bubbles from between the medium and the printing table;
the printing table includes a plurality of vacuum holes in a surface of the printing table;
a suction device is arranged to apply suction to the plurality of vacuum holes; and
a control device is arranged to control the suction device such that suction is applied to a vacuum hole of the plurality of vacuum holes or to a section including more than one of the plurality of vacuum holes only after the pressing rail passes over the vacuum hole or the section including more than one of the plurality of vacuum holes.
2. The flatbed printing machine according to claim 1 , wherein the traversing device includes a motor operatively connected to the first and second guide carriages.
3. The flatbed printing machine according to claim 1 , wherein the traversing device includes first and second drive belts connected to the first and second guide carriages, respectively, a plurality of pulleys arranged to guide the first and second drive belts, and a motor arranged to drive the first and second drive belts.
4. The flatbed printing machine according to claim 1 , wherein the lifting device includes at least one pneumatic cylinder operatively connected to the pressing rail.
5. The flatbed printing machine according to claim 1 , wherein the plurality of vacuum holes are arranged in rows parallel or substantially parallel to the pressing rail on the printing table, and a respective row including more than one of the plurality of vacuum holes or a section including a plurality of combined rows is subjected to suction at one time.