Image formation control method and image forming apparatus

1 . An image formation control method for controlling an image forming apparatus including: a roll paper supply device configured to roll out roll paper and cut a rolled-out portion of the roll paper to produce a first sheet of a specific size, and convey the first sheet to a specific conveying path; a cut sheet supply device configured to convey a second sheet cut to the specific size in advance and accommodated in an accommodating portion to the specific conveying path; a printing device configured to execute a print process of forming an image on the first sheet or the second sheet conveyed through the specific conveying path to a print position; and a sensor configured to detect the first sheet at a specific position between a position at which the roll paper is cut in the roll paper supply device and the specific conveying path, the image formation control method comprising:

when continuous print processing in which the print process is repeated a plurality of times is executed,

determining, by a control device based on a detection state of the sensor, whether or not the roll paper supply device is in a specific state in which the roll paper supply device has conveyed the first sheet to the specific position, for each of the print processes;

causing, by the control device, the roll paper supply device to execute a process of conveying the first sheet toward the print position when it is determined that the roll paper supply device is in the specific state, for each of the print processes; and

causing, by the control device, the cut sheet supply device to execute a process of conveying the second sheet toward the print position when it is determined that the roll sheet supply device is not in the specific state, for each of the print processes.

2 . The image formation control method according to claim 1 , further comprising:

determining, by the control device, whether or not the roll paper supply device is in a sheet produced state in which the roll paper supply device has already produced the first sheet when a last print process of the print processes in the continuous print processing is executed; and

causing, by the control device, the roll paper supply device to execute a process of conveying the first sheet toward the print position regardless of a conveyance position of the first sheet when it is determined that the roll paper supply device is in the sheet produced state when a last print process of the print processes in the continuous print processing is executed.

3 . The image formation control method according to claim 1 , further comprising:

repeatedly determining, by the control device, whether or not the roll paper supply device is in a normal state in which the roll paper supply device is able to supply the first sheet in a sheet feed operation period from when the control device receives a request for the continuous print processing to when a last print process of the print processes in the continuous print processing is executed; and

repeatedly causing, by the control device, the roll paper supply device to execute a process of producing the first sheet and conveying the first sheet to the specific position when it is determined that the roll paper supply device is in the normal state during the sheet feed operation period.

4 . An image forming apparatus comprising:

a roll paper supply device configured to roll out roll paper and cut a rolled-out portion of the roll paper to produce a first sheet of a specific size, and convey the first sheet to a specific conveying path;

a cut sheet supply device configured to convey a second sheet cut to the specific size in advance and accommodated in an accommodating portion to the specific conveying path;

a printing device configured to execute a print process of forming an image on the first sheet or the second sheet conveyed through the specific conveying path to a print position;

a sensor configured to detect the first sheet at a specific position between a position at which the roll paper is cut in the roll paper supply device and the specific conveying path; and

a control device configured to implement the image formation control method according to claim 1 .