Position transducer for use with a printer or plotter
US4844317A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 1987 |
| Grant date | Jul 4, 1989 |
| Priority date | — |
| Expiry date | Jul 24, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D15/28
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A rigid link is provided between a plot medium (14) and a position transducer (50) so that accurate plot medium advance measurement can be attained. The device (30) comprises a movable carriage (42) and an arm-like extension (38) that juts out from the carriage to the plot medium. A friction hold is made between the extension arm and the plot medium by applying a force to the extension arm normal to the plot medium by means of an electromagnet (33) which includes a coil (34), the extension arm serving as the armature. The electromagnet is located beneath the platen (12) which supports the medium on a base (32) which also supports the carriage. With the electromagnet activated, the extension arm is held against the plot medium. As the plot medium is advanced by a plot medium drive system (20), the extension arm and carriage are pulled along. Plot medium advance is stopped when the proper advance distance has been sensed by the position transducer. The electromagnet is then deactivated and the extension arm and carriage are retracted by a return spring (48) to their original position. The process can then be repeated for the next plot medium advance. The length of a single move is sh…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.