Patent · US Expired

Plotter stylus with cap covered vent

US4712937A · kind A · utility

42Cited by

11References

1Claims

0Family size

Assignee

Schmidt Feintechnik GmbH · DE

Inventors

Rolf Schmidt · Waldbronn, DE
Roland Schneider · Schotten, DE

Key dates

Filing date	Apr 9, 1985
Grant date	Dec 15, 1987
Priority date	—
Expiry date	Apr 9, 2005

Classification

Technology area (CPC B)Performing Operations; Transporting
CPC primaryB43K7/105
WIPO fieldOther consumer goods
WIPO sectorOther fields

Abstract

The plotter stylus has a writing point (10) which is connected to the ink cartridge (50) via the ink duct (40). The ink duct (40) is surrounded by a pressure compensator (20) and connected thereto. In the pressure compensator a compensator element (21) is provided with annular chambers (23) which absorb surplus ink emerging from the ink duct (40) in the case of temperature or pressure increases. The annular chambers have no capillarity for the ink. Air is introduced via the air inlet orifice (28) located above the chambers (23). The ink cartridge (50) is exchangeable.

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