Thermally reversible printing system with ambient temperature compensation
US5453765A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 17, 1994 |
| Grant date | Sep 26, 1995 |
| Priority date | — |
| Expiry date | Feb 17, 2014 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2/365
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A printing system for recording and erasing a visible image onto and from a recording medium presenting two states, recording and erasing, by different heating processes, comprises a temperature sensor for sensing ambient temperature, a thermal head, a circuit for computing the temperature difference between a reference ambient temperature and the ambient temperature obtained from the sensor, a circuit for controlling the electrically energizing time of the thermal head in accordance with the temperature difference obtained at the computing circuit, and means for controlling the supply voltage to the thermal head according to the temperature difference. When ambient temperature around the system is lower than the reference ambient temperature, the electrically energizing time of the thermal head is increased. When the ambient temperature is higher than the reference ambient temperature, the supply voltage to the thermal head is decreased. By recording or erasing a visible image in this way, the effect of ambient temperature is corrected, thereby making it possible to always record or erase a visible image onto or from a recording medium stably.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.