Ink detecting device for a liquid-ink printing element.

摘要

The ink detecting device gives advance warning of the end of the ink in a reservoir or cartridge feeding an ink-jet thermal print head. The device comprises a pair of electrodes (54) that are immersed in a spongy, ink-soaked body (50) contained in the reservoir (10), and are arranged in a region (A) adjacent to the aperture (30) for the feed duct (34) at which the spongy body has a 30% to 100% higher capillarity than in remote regions. The electrodes are connected to a bridge circuit (Figure 5) which measures the electrical resistance of the ink between the two electrodes. <IMAGE>