INK CARTRIDGE AND INK JET RECORDER

摘要

PROBLEM TO BE SOLVED: To detect open state of the atmosphere opening valve of an ink cartridge. SOLUTION: The ink jet printer comprising an ink cartridge 1 for preventing the degree of deaeration from lowering by closing a valve element 26 with the energizing force of a leaf spring 25 when an arm 29 for opening an ink supply opening 10 and the valve element 26 for opening ink to the atmosphere and an ink cartridge 1 are not set in a cartridge holder, and a cartridge holder being set removably with the ink cartridge 1 and having an ink supply needle 33 continuous to the print head 2 and a protrusion 30 for pushing in the arm 29 of the ink cartridge 1 is further provided with means for detecting the open/ close state of the valve element 26 for opening ink to the atmosphere as the ink cartridge 1 is set in the cartridge holder.