Inventors:
Gary E. Hanson - Boise ID
Gar P. Kelly - Boise ID
C. S. Chan - Boise ID
Bruce Cowger - Corvallis OR
James G. Bearss - Boise ID
Assignee:
Hewlett-Packard Company - Palo Alto CA
International Classification:
G01D 1516
G01D 900
Abstract:
This application is directed to an ink jet pen having an ink supply housing which includes a primary ink reservoir (30) and a secondary ink reservoir (26). A balancing capillary member is positioned within the ink supply housing and includes ink flow path (20, 24) which extends between the primary ink reservoir (30) and the secondary ink reservoir (26). This capillary member is operative to draw ink from the primary ink reservoir (30) and into or toward the secondary ink reservoir (26) by capillary action as temperature and pressure within the primary ink reservoir increases. Conversely, when temperature and pressure in the housing decreases, ink will be drawn back into or toward the primary ink reservoir (30). In addition, the primary ink reservoir (30) is connected by way of a suitable ink feed path to an ink jet printhead (32) for supplying ink to the printhead during an ink jet printing operation.