The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 13, 2004
Filed:
Jul. 25, 2002
Ching-Yu Chou, Taipei, TW;
Wen-Chung Chen, Hsinchu, TW;
Chien-Ming Lin, Taipei, TW;
Chuang-Hsien Chiu, Hsinchu, TW;
Nanodynamics Inc., Hsinchu Hsien, TW;
Abstract
An inkjet pen including an ink reservoir for storing ink and providing ink for jetting. A port, located on top of the ink reservoir, fluid-communicated with the ambient air, is used for adjusting the air pressure inside the reservoir. A valve, operated by a spring or a resilient element, normally seals the port, while occasionally opening the port to introduce air into the reservoir when the ink level is low and the underpressure rises. In other embodiments, an elastic bag is included in the reservoir that has an opening communicated with the ambient air through a second port formed on top of the reservoir. The elastic bag expands in response to the increasing underpressure generated in the reservoir when ink is being used. The bag expansion actuates the opening of the valve so as to regulate the underpressure.