EC-PACK EC-JET 2000, Manual

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User Manual The1.1 version of 2018 Guangzhou EC-PACK CO.LTD
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travel between two deflector plates. When the drops reach the product, they form one line of drops
called a raster. As the product passes under the print head, rasters are laid down side by side to
form the printed message.
2.2.6. Ideal Pitch
Unprinted drops in a raster carry no charge and are therefore not deflected. These drops are
captured by a gutter in the print head, and returned to ink tank. Gaps between raster (perhaps to
separate readable characters) are created by the printer simply not printing a raster as the product
continues to move past the printhead.
2.2.7. Detecting Products
A photocell or product detecting sensor is used to inform the printer when the product has been
detected. After a predefined delay, the first raster of the pattern will be printed, followed by the
remaining rasters of the pattern, as described above.
2.2.8. Conveyor Speed
For production setups using a conveyor, variation in conveyor speed can produce variation in the
appearance of the printed message. If the product is moving very slowly, the rasters could be
printed too close together and the characters formed would be too thin. Conversely, if the product
is moving very fast, the rasters could be printed too far apart, resulting in unprinted gaps between
the rasters. This problem is overcome by either varying the print width (through a user menu
option) to match the production of rasters with the conveyor speed, or by using a shaft encoder to
control the rate at which each raster is printed in relation to the conveyor movement.
2.2.9. Ink Blockage Prevention
It is essential to use the correct solvent for the ink being used, i.e. the solvent used in
the ink base: MEK solvent for MEK based ink, ETHANOL solvent for ETHANOL
based ink,etc.
The principle of continuous ink jet printing has proved to be the most effective means
of printing with an ink which is required to dry instantly, within a second, on almost
any surface.
2.2.10. Blockages
If ink is required to dry on the product it will also have a tendency to dry in the printer, with a
possibility of causing a blockage.
The continuous ink jet printer overcomes this problem by continuously producing the print drops
in operation. Although the ink is evaporating quickly during this process, it does not cause a
nozzle blockage, as there is a constant replacement of ink in the nozzle.
2.2.11. Automatic Cleaning at Start and Shutdown
A potential problem arises on shutdown when ink is left in the nozzle; as it is fast drying it will
soon dry and clog up the nozzle. To overcome this, special procedures to clean at start and
shutdown are necessary.
EC2000 printer is equipped with a cleaning pump. A special cleaning nozzle,a micro valve and a
washing line are arranged in the printhead. It executes an automatic cleaning procedure during