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. 10, 2001
Filed:
Feb. 12, 1999
I. C. Hou, Hsinchu, TW;
Chi-Chien Lin, Hsinchu Hsien, TW;
Industrial Technology Research Institute, Hsinchu, TW;
Abstract
A pressure control device installed at the bottom of the reservoir of an ink-jet pen. The device has a tubular boss whose upper end has an arc surface and that a sphere sits on the arc surface. Ideally, the sphere makes a line contact with the arc surface of the boss. The device also has a spring with one end mounted to the bottom of the reservoir. The spring has two portions together. The first portion of the spring presses tightly against the sphere while the second portion touches a pressure plate inside the reservoir. The reservoir further contains an expandable bag. When the bag inside the reservoir expands, the pressure plate attached to the bag will push the second portion of the spring such that its first portion will move away from the sphere. Due to the presence of a back pressure within the reservoir, the sphere will be afloat briefly permitting ambient air to enter the reservoir. Consequently, back pressure within the reservoir is regulated.