Cartridge, ink jet print head and ink jet printer

A cartridge, comprising:

• a cartridge body with an opening and an ink flow aperture, wherein an ink reservoir for containing ink is formed within the cartridge body;
• and
• a cartridge lid for covering the opening, wherein the cartridge lid is provided with an ink filling hole and a venting hole;
• and
• wherein
• the cartridge lid is further provided with ribs on the inner surface thereof;
• and
• the cartridge further comprises a soft member provided between the cartridge lid and the opening and overlapping the venting hole but not overlapping the ink filling hole, when the cartridge lid is mounted to the cartridge body and covers the opening, the ribs abut against the soft member so that a sealing contact is formed between the ribs and the soft member and an expansion space is formed between the cartridge lid and the soft member, wherein the expansion space has an inlet through which ink is able to flow into the expansion space from the ink reservoir, and the expansion space is in communication with external environment through the venting hole, wherein the expansion space is an expansion circuit which is circuitous.