Pressure controller for an ink cartridge

Abstract

The ink cartridge is provided with a pressure controller to regulate the inner pressure therein by atmospheric pressure while the ink stored in the ink cartridge is gradually drained off. The ink is stored in a container with negative pressure therein, and at least one through hole formed on the container is used to connect to the atmosphere, and at least one recess is formed on the inner wall of the through hole. The pressure controller has a plug movably disposed on the through hole and the recesses. The recesses are used as a channel to allow the entrance of the atmospheric air, and the plug can be automatically moved so as to enlarge the clearance between the plug and the through hole while the ink stored in the ink cartridge is gradually drained off. The inputted air can effectively reduce the negative pressure in the container, and therefore the printing process of the ink cartridge can be proceeding steadily.

Dependencies are inferred from the claim text.