Patent · US Expired

Uniform print density and registration in an impact printer

US4806031A · kind A · utility

2Cited by

10References

8Claims

0Family size

Assignee

Data Products Corporation · US

Inventors

Paul Amdahl · Sioux City, US
John Ham · Craydon Court, US
Doina Mazilu · Calabasas, US

Key dates

Filing date	Aug 15, 1986
Grant date	Feb 21, 1989
Priority date	—
Expiry date	Aug 15, 2006

Classification

Technology area (CPC B)Performing Operations; Transporting
CPC primaryB41J9/48
WIPO fieldTextile and paper machines
WIPO sectorMechanical engineering

Abstract

Commencing with the first print hammer(s) "out", or actuated, on each print line the hammer drive current is boosted 10% for a period, ranging from 25%=650 microseconds for single part forms to 50% for multi-part forms, of the total print hammer flight time. Earlier striking hammers on each print line strike harder, alleviating displaced first-printed characters on single part forms and light characters on multipart forms due to hammer energy loss in forms compression.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.