Patent · US Expired

Ink level detection system for ink jet printing apparatus

US4639738A · kind A · utility

190Cited by
1References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 12, 1985
Grant dateJan 27, 1987
Priority date
Expiry dateApr 12, 2005

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB41J2/17566
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

The detection system includes a cartridge having a first detection port for detecting the pressure condition in the top portion of the cartridge and a second detection port and tube for detecting the pressure condition in a bottom portion of the cartridge. The cooperative printer structure couples these ports to a pressure differential sensor that signals a printer refill condition.

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