Print head carriage homing system
US5074690A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 1990 |
| Grant date | Dec 24, 1991 |
| Priority date | — |
| Expiry date | Jun 26, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J19/207
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A printer has a bi-directional stepper motor that drives an endless toothed belt which is secured to a print head carriage for driving the carriage back and forth across the printer along a line of printing. A timing strip is molded integral with the frame of the printer and positioned under the print head carriage. An optical sensor of the light emitting diode and phototransistor type is secured to the underside of the carriage and positioned to straddle the timing strip as the carriage is driven back and forth across the printer. The printer controller uses timing strip/sensor signals to place the print head in a home position when the printer is turned on and also when the print head has been moved from an operating position, e.g. in the case of changing a ribbon. The timing strip/sensor signals are also used to detect a carriage jam condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.