Inkjet printer gas pressure controller provided with negative pressure test line, inkjet printer including gas pressure controller, and method of testing negative pressure in inkjet printer

An inkjet printer comprising a gas pressure controller provided with a negative pressure test line, the inkjet printer comprising:

• an inkjet head provided with a nozzle for discharging ink;
• an ink storage unit configured to store the ink to supply the ink to the inkjet head;
• and
• the gas pressure controller connected to the ink storage unit and configured to control internal pressure so that the ink stored in the ink storage unit maintains a meniscus state in the inkjet head,
• wherein the gas pressure controller comprises:
• a negative pressure generation unit capable of suctioning air and applying negative pressure through an output tube;
• a positive pressure generation unit capable of exhausting the air and applying positive pressure through the output tube;
• the negative pressure test line capable of testing the negative pressure generated by the negative pressure generation unit when connected to the negative pressure generation unit;
• and
• a pressure control module for controlling the negative pressure or positive pressure to be applied through the output tube by controlling a connection relationship between the negative pressure generation unit, the positive pressure generation unit, and the output tube, and
• the pressure control module operates to connect the negative pressure generation unit and the negative pressure test line to each other when connecting the positive pressure generation unit and the output tube to each other in order to apply the positive pressure through the output tube.

A method of testing negative pressure in an inkjet printer, the method comprising:

• testing the negative pressure of a gas pressure controller in the inkjet printer comprising an inkjet head provided with a nozzle for discharging ink, an ink storage unit configured to store the ink to supply the ink to the inkjet head, and the gas pressure controller connected to the ink storage unit and configured to control internal pressure so that the ink stored in the ink storage unit maintains a meniscus state in the inkjet head,
• wherein the gas pressure controller comprises:
• a negative pressure generation unit capable of suctioning air and applying the negative pressure through an output tube;
• a positive pressure generation unit capable of exhausting the air and applying positive pressure through the output tube;
• a negative pressure test line capable of testing the negative pressure generated by the negative pressure generation unit when connected to the negative pressure generation unit;
• and
• a pressure control module for controlling the negative pressure or positive pressure to be applied through the output tube by controlling a connection relationship between the negative pressure generation unit, the positive pressure generation unit, and the output tube, and
• the pressure control module operates to connect the negative pressure generation unit and the negative pressure test line to each other when connecting the positive pressure generation unit and the output tube to each other in order to apply the positive pressure through the output tube, and performs a negative pressure test through the negative pressure test line connected to the negative pressure generation unit in a state where the gas pressure controller applies the positive pressure to the ink storage unit in a process of using the inkjet printer.