Abstract: An image formation device has an image carrier in which is formed a latent image and a development device in which are detachably mounted a plurality of development units housing a developing agent. When development units of a plurality of colors, used to form color images are mounted in respectively predetermined mounting positions of the development device, operation is in color printing mode; and, a development unit of a single color among the development units of the plurality of colors is mountable in any mounting position of the plurality of mounting positions, and when the development unit of a single color is mounted in any of the positions of the plurality of mounting positions, operation is in monochrome printing mode.

Abstract: When a plurality of development units holding toner of the same color are mounted in an image formation device, an error or warning or the like is displayed on the image formation device or the error or warning is outputted to a host on the basis of the total amount of toner remaining in the plurality of development units. In addition, printing is executed continuously even when a certain toner has run out or is about to run out. An image formation device in which a plurality of development units holding toner of the same color can be mounted is characterized in that the remaining amount of all the toner of the development units holding toner of the same color is managed.

Abstract: An image formation device has an image carrier in which are formed latent images, and a development device into which development units housing toner are detachably installed. When development units with a plurality of colors are installed in respective installation positions of the development device, the image formation device operates in color printing mode, and when at least one black development unit is installed in any among the plurality of installation positions, and at least one among the development units with the colors other than black is not installed, even if at least one development unit in the plurality of colors other than black is installed, the image formation device operates in monochrome printing mode. When any of the C, M, and Y development units is removed from color mode state, the image formation device operates in monochrome printing mode.

Abstract: An image forming device has an image carrier (20) and a development device (50) in which development units (51-54) are detachably attached, and the development units has a memory for storing color information and remaining amount information of development agent. The image forming device operates as a monochrome printing mode when single color development units are attached at attachment positions of the development device, further has a display unit (95) for displaying a remaining amount of developing agent in the development units, and a control unit for obtaining an initial total amount of developing agent in an initial state and a current total remaining amount of developing agent of attached development units, and for displaying on the display unit the initial total amount and the total remaining amount. By displaying the initial and current total amount of development units, the convenience of replacement administration of development units can be improved.

Abstract: When a plurality of development units holding toner of the same color are mounted in an image formation device, an error or warning or the like is displayed on the image formation device or the error or warning is outputted to a host on the basis of the total amount of toner remaining in the plurality of development units. In addition, printing is executed continuously even when a certain toner has run out or is about to run out. An image formation device in which a plurality of development units holding toner of the same color can be mounted is characterized in that the remaining amount of all the toner of the development units holding toner of the same color is managed.

Abstract: An image formation device has an image carrier in which are formed latent images, and a development device into which development units housing toner are detachably installed. When development units with a plurality of colors are installed in respective installation positions of the development device, the image formation device operates in color printing mode, and when at least one black development unit is installed in any among the plurality of installation positions, and at least one among the development units with the colors other than black is not installed, even if at least one development unit in the plurality of colors other than black is installed, the image formation device operates in monochrome printing mode. When any of the C, M, and Y development units is removed from color mode state, the image formation device operates in monochrome printing mode.

Abstract: An image formation device has an image carrier in which is formed a latent image and a development device in which are detachably mounted a plurality of development units housing a developing agent. When development units of a plurality of colors, used to form color images are mounted in respectively predetermined mounting positions of the development device, operation is in color printing mode; and, a development unit of a single color among the development units of the plurality of colors is mountable in any mounting position of the plurality of mounting positions, and when the development unit of a single color is mounted in any of the positions of the plurality of mounting positions, operation is in monochrome printing mode.