Abstract: A print head device has a seal packing and pressure fluctuation-accommodating structure. The seal packing is arranged such that when an ink cartridge storing ink therein and having an ink delivery port for delivering the ink therefrom is mounted in the print head, the seal packing is brought into airtight contact with the ink cartridge such that the seal packing encloses the ink delivery port, thereby defining an inner space within the seal packing, for airtight communication between the ink delivery port and the inner space. The pressure fluctuation-accommodating structure accommodates pressure fluctuations within the ink delivery port and the inner space in communication with each other. Alternatively, the ink cartridge includes the pressure fluctuation-accommodating structure. An ink jet printer includes the print head device.

Abstract: There are provided a print head device, an ink jet printer incorporating the print head device, and an ink cartridge for use in the ink jet printer. The ink cartridge has an ink delivery spout, a delivery spout-sealing film for sealing the ink delivery spout, an air inlet passage, and an air inlet passage-sealing film for sealing the air inlet passage. The print head device has a cartridge holder for removably receiving the ink cartridge therein, a print head, and a hollow head needle in communication with the print head. A pusher member pushes inward the ink cartridge in a state provisionally received in the cartridge holder until the head needle pierces the delivery spout-sealing film such that the head needle is inserted into the ink delivery spout, thereby causing the ink cartridge to be completely received in the cartridge holder.

Abstract: There is provided an ink cartridge which prevents ink from spilling out when the ink cartridge is mounted in a printer. An ink supply block of the ink cartridge is formed with a delivery port opening in a bottom of the ink supply block and a supply passage extending inward from the delivery port. A filter is provided at an upstream end of the supply passage. A lid member, which has a complementary shape to the supply passage, is removably mounted in the supply passage from the delivery port.

Abstract: A printhead unit is detachably coupled to an ink cartridge. The printhead unit includes an ink passage and a damper member for absorbing a pulsation of ink in the ink passage. The damper member permits the forces created when the ink cartridge receives an impact to be absorbed rather than translated through to the printhead, thereby destroying the meniscuses in the nozzles.