Image forming apparatus and method for operating image forming apparatus

1 . An image forming apparatus, comprising:

one or more controllers; and

an image former having one or more detachable fixing units,

wherein:

the one or more controllers acquire fixing unit information on a fixing unit attached to the image former, and execute a predetermined process, based on the acquired fixing unit information,

the fixing unit information comprises identification information for uniquely identifying the fixing unit, and

the predetermined process comprises determining a size of sheets, on which image formation using the fixing unit is permitted, based on the identification information, and determining whether to execute image formation on the sheets, using the image former, based on a result of the predetermined process, wherein

the one or more controllers:

in a case that the size of sheets is a first size, permit the execution of image formation on sheets of the first size, and restrict the execution of image formation on sheets other than the first size; and

in a case that a number of times the image formation has been executed on the sheets of the first size becomes greater than a predetermined number, restrict the execution of image formation on the sheets of the first size, and permit the execution of image formation on sheets of a second size, smaller than the first size.

2 . The image forming apparatus according to claim 1 , further comprising:

a display,

wherein the predetermined process further comprises displaying at least one of the fixing unit information, and information determined based on the fixing unit information, on the display.

3 . The image forming apparatus according to claim 1 , wherein:

the sheets have a rectangular shape, and

the one or more controllers determine whether to execute image formation on the sheets by using a length of a side of the sheets, which is substantially orthogonal to a transport direction of the sheets, as a reference length.

4 . The image forming apparatus according to claim 1 , further comprising:

a display,

wherein the one or more controllers display, on the display, a sheet size on which the image information is permitted and a sheet size on which the image formation is restricted in different display modes.

5 . The image forming apparatus according to claim 1 , wherein the one or more controllers restrict image formation performed by the image former on sheets of the sheet size on which the image formation is restricted.

6 . A method for operating an image forming apparatus comprising an image former having one or more detachable fixing units, the method comprising:

acquiring fixing unit information on a fixing unit attached to the image former, and

executing a predetermined process, based on the acquired fixing unit information,

wherein:

the fixing unit information comprises identification information for uniquely identifying the fixing unit, and

the predetermined process comprises determining a size of sheets, on which image formation using the fixing unit is permitted, based on the identification information, and determining whether to execute image formation on the sheets, using the image former, based on a result of the predetermined process,

in a case that the size of sheets is a first size, the execution of image formation is permitted on sheets of the first size, and the execution of image formation is restricted on sheets other than the first size, and

in a case that a number of times the image formation has been executed on the sheets of the first size becomes greater than a predetermined number, the execution of image formation is restricted on the sheets of the first size, and the execution of image formation is permitted on sheets of a second size, smaller than the first size.