Printing apparatus and method for preventing printing errors in same
US4398837A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1982 |
| Grant date | Aug 16, 1983 |
| Priority date | — |
| Expiry date | Mar 23, 2002 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J1/24
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A printing apparatus comprising a print wheel having a multiplicity type elements, and a detecting unit for detecting angular positions of the print wheel including its fixed home position. The apparatus further comprises a control unit which includes a first counter which stores data representative of an angular distance of a type element currently located at the printing position as measured from the home position, and a second counter which stores data representative of an angular position of a type element designated by a print signal. Both counters are operated as they receive position signals from the detecting unit. The control unit is so arranged that in the event of an unexpected rotation of a wheel driving rotary shaft which is not a result of the actuation of a wheel driving motor in response to the print signal, the print wheel is first reset to the home position before it is rotated to bring a designated type element to the printing position, whereby chances for printing errors due to such unexpected rotation are eliminated. A method for controlling to prevent the printing errors is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.