Inkjet printing apparatus and method for performing maintenance on inkjet printing apparatus

An inkjet printing apparatus using print heads for ejecting liquid droplets from ejection ports to a printing medium for printing, comprising:

• a sub-droplet collecting portion that collects sub-droplets each having a smaller liquid volume than that of a main droplet in each of the liquid droplets produced by the ejection;
• a sub-droplet amount calculating mean that calculates the amount of sub-droplets generated on the basis of printing conditions including a shape of the ejection ports of the print heads;
• and
• a replacement necessity determining mean that determines whether or not the sub-droplet collecting portion is replaced, on the basis of the amount of sub-droplets generated which has been calculated by the sub-droplet amount calculating mean.

An inkjet printing apparatus using print heads for ejecting liquid droplets to a printing medium from a plurality of ejection port rows for printing, comprising:

• a sub-droplet collecting portion that collects sub-droplets each having a smaller liquid volume than that of a main droplet in each of the liquid droplets produced by the ejection;
• a sub-droplet amount calculating mean that calculates the amount of sub-droplets generated on the basis of printing conditions including order of ejecting the liquid droplet from the ejection ports in the ejection port rows;
• and
• a replacement necessity determining mean that determines whether or not the sub-droplet collecting portion is replaced, on the basis of the amount of sub-droplets generated which has been calculated by the sub-droplet amount calculating mean.

A method of performing maintenance on an inkjet printing apparatus using print heads for ejecting liquid droplets to a printing medium for printing, comprising:

• a process of collecting sub-droplets each having a smaller liquid volume than that of a main droplet in each of the liquid droplets produced by the ejection;
• a temperature obtaining process for obtaining temperature information of the print heads;
• a sub-droplet amount calculating process for calculating the amount of sub-droplets generated on the basis of printing conditions including the temperature information of the print heads;
• and
• a replacement necessity determining process for determining whether or not a replacement of a sub-droplet collecting portion for collecting the sub-droplets is necessary in accordance with the amount of sub-droplets collected of the calculated sub-droplets.

A method of performing maintenance on an inkjet printing apparatus using print heads for ejecting liquid droplets to a printing medium from ejection ports for printing, comprising:

• a process of collecting sub-droplets each having a smaller liquid volume than that of a main droplet in each of the liquid droplets produced by the ejection;
• a sub-droplet amount calculating mean for calculating the amount of sub-droplets generated on the basis of printing conditions including a shape of the ejection ports of the print heads;
• and
• a replacement necessity determining process for determining whether or not a replacement of a sub-droplet collecting portion for collecting the sub-droplets is necessary in accordance with the amount of sub-droplets collected of the calculated sub-droplets.

A method of performing maintenance on an inkjet printing apparatus using print heads for ejecting liquid droplets to a printing medium from ejection port rows of ejection ports for printing, comprising:

• a process for collecting sub-droplets each having a smaller liquid volume than that of a main droplet in each of the liquid droplets produced by the ejection;
• a sub-droplet amount calculating process for calculating the amount of sub-droplets generated on the basis of printing conditions including order of ejecting the liquid droplet from the ejection ports in the ejection port rows;
• and
• a replacement necessity determining process for determining whether or not a replacement of a sub-droplet collecting portion for collecting the sub-droplets is necessary in accordance with the amount of sub-droplets collected of the calculated sub-droplets.

An inkjet printing apparatus comprising:

• a print head in which a plurality of ejection ports are arranged and generating sub-droplets in accordance with main droplets, each sub-droplets having a smaller liquid volume than that of a main droplet;
• a control unit for controlling the performing of printing to the print medium by controlling the ink ejection by the print head;
• a drive controlling unit for dividing the ejection ports of the print head into a plurality of blocks and for ejecting ink from ejection ports of each block by driving, said drive controlling unit being capable of changing the order of the blocks for the ink ejection;
• a distance detecting unit for detecting the distance between the print head and the printing medium;
• a sub-droplet collecting portion mounted to the inkjet printing apparatus replaceable, for collecting the sub-droplets generated in accordance with ejecting the main droplets;
• a temperature obtaining mean that obtains temperature of the print heads;
• and
• a replacement necessity determining mean that determines whether or not the sub-droplet collecting portion is replaced on the basis of the amount of sub-droplets generated which has been calculated by the sub-droplet amount calculating mean by using the temperature obtained by the temperature obtaining mean, the distance detected by the distance detecting unit and the order of the blocks for the ink ejection set by the drive controlling unit.