Thick film print head structure and control circuit
US9186905B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 2012 |
| Grant date | Nov 17, 2015 |
| Priority date | — |
| Expiry date | Sep 6, 2032 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2/355
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A new structure (FIG. 11) for a thick-film thermal printhead and a variety of implementation approaches for controlling such a printhead. In the structure of the invention, the conductive lead at each end of the heater element is switched to either the power supply (Vhd) or ground, depending on the corresponding nib data bit. The improvement over a traditional center-tap structure (FIG. 1) is the reduction of density of conductive leads to achieve the resolution of printed dots. Compared to the printhead structure of alternated conductive system, either with diodes (FIG. 2) or without diodes (FIG. 4), which both suffer from the introduction of undesirable leaking currents, the printhead structure of the invention provides the advantage of eliminating leakage current completely. Control of the thermal printhead according to the invention is based on the sequential exclusive-OR (XOR) logic operation applied to the shifted-in nib data bit stream. The XOR functionality may be incorporated in the driver IC, embedded in the raster data processing FPGA (Field Programming Gate Array), or implemented in the form of a lookup table in the memory block of a main processor system. All prior art…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.