| CPC B41J 2/17566 (2013.01) [B41J 2/17513 (2013.01); B41J 2/17596 (2013.01); B41J 2002/17516 (2013.01)] | 15 Claims |

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1. A device for determining an empty ink state of an ink container for an ink printing system, wherein the ink container has a rigid outer container and an inner, flexible fluid pouch, the device comprising:
a fluid conduit connected to the inner fluid pouch;
a pump connected to the inner fluid pouch via the fluid conduit, the pump configured to convey fluid out of the inner fluid pouch; and
an evaluation unit operatively connected to the pump,
wherein the pump is configured to output an electrical signal whose periodicity is proportional to a rotational speed of the pump, and
wherein the evaluation unit is configured to monitor a frequency of the electrical signal and, upon the frequency falling below a predetermined threshold, to output that the ink container is empty.
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