Inkjet printing device and ink remaining quantity detection method in inkjet printing device

A method for detecting a remaining ink amount in an inkjet printing apparatus including a first tank which stores ink, a second tank which stores ink, a printer section including an inkjet head which ejects ink droplets toward a printing medium, a first supply system which supplies ink from the first tank to the second tank, and a second supply system which includes an ink supply pump and supplies ink from the second tank to the printer section, the method comprising:

• a transferred ink amount calculation step of calculating an amount of ink transferred from the first tank to the second tank in a measurement period during which ink is supplied from the first tank to the second tank, based on an increase in an amount of the ink stored in the second tank in the measurement period and an operation state of the pump in the measurement period;
• and
• a remaining amount detection step of detecting an amount of ink remaining in the first tank at end of the measurement period by subtracting the transferred ink amount from an amount of ink remaining in the first tank at start of the measurement period.