Replaceable assembly for multicolor printing
US4368993A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 1981 |
| Grant date | Jan 18, 1983 |
| Priority date | — |
| Expiry date | Apr 30, 2001 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J35/14
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A computer controlled impact printer has a replaceable ribbon guide assembly mounted on a printhead. The assembly is movable vertically between at least two stable positions. Each position places a differently colored portion of the ribbon between the printhead and a sheet of paper. Rotation of a pair of opposed cams changes the vertical position of the assembly. One cam is fixed and the other is rotatable by a pawl operating on a ratchet wheel secured to the cam. The pawl is mounted on the assembly for a longitudinal sliding movement. Movement of the printhead to a preselected position at or near one end of its travel path drives the pawl into an abutment surface which displaces the pawl a predetermined distance. The displacement rotates the movable cam from one stable vertical position to another. The mating cam surfaces preferably have matching sawtooth configurations with recesses formed in the tips of the teeth of one cam. The cams are biased towards one another and the pawl is biased towards the abutment surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.