Daisy wheel printer having low mass carriage
US4440512A · kind A · utility
Inventor
Key dates
| Filing date | Jun 7, 1982 |
| Grant date | Apr 3, 1984 |
| Priority date | — |
| Expiry date | Jun 7, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S400/903
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A daisy wheel printer with a low mass carriage is driven by a pair of bidirectional stepping motors mounted on the printer frame. The carriage and print wheel are each driven by their respective motor through a belt and pulley drive extending side to side of the printer frame. The motors and pulleys are proportioned so that a step of either stepping motor rotates the print wheel from one character position to the next, thereby synchronizing print wheel rotation with carriage movement. The motors are driven independently, under control of a microcomputer in the printer, to vary the phase of rotation of the print wheel relative to movement of the carriage. Stops at one end of the printer frame are used to physically position the carriage and wheel to known initial locations. The microcomputer is programmed to electrically synchronize the motor controls to such locations and to track the positions of the print wheel and carriage when moving them from their initial locations, without using extrinsic position-sensing and control circuitry. The printer has a platen mounted on a rack which is pivotable by rotatable cams away from the print wheel to ease removal of the wheel and to optimal…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.