Image forming apparatus and image forming method

An image forming apparatus comprising:

• an electrostatic latent image carrier for carrying an electrostatic latent image on a peripheral surface thereof;
• a plurality of development units each accommodating a toner and adapted to develop the electrostatic latent image by the toner;
• a development unit holder capable of holding said plurality of development units;
• and
• a control unit for said development unit holder for controlling an operation of said development unit holder and for selectively changing over said plurality of development units to be used in a development,
• wherein when an amount of toner consumed in a first development unit of said development units that is in use in the development has reached a predetermined amount, said development unit holder is rotated 360 degrees for agitating the toner in said first development unit to continue the development using said first development unit.

A method of forming an image by an image forming apparatus in which color information on a toner accommodated in a plurality of development units held in a development unit holder is identified by an identifying device, and said development unit used in development is selectively changed over among said plurality of development units by a control unit for controlling said development unit holder, so as to effect a development, comprising the steps of:

• selecting one of said development units that is used in the development;
• rotating said development unit holder 360 degrees for agitating the toner in said selected development unit, when an amount of toner consumed in said selected development unit has reached a predetermined amount;
• and
• continuing the development using said selected development unit.

An image forming apparatus comprising:

• an electrostatic latent image carrier for carrying an electrostatic latent image on a peripheral surface thereof;
• a plurality of development units each accommodating a toner and adapted to develop the electrostatic latent image by the toner;
• a development unit holder capable of holding said plurality of development units;
• and
• a control unit (14) including a controller portion (38) for processing image information and an engine control portion (35) that identifies at least color information on toner accommodated in each development unit and controls said development unit holder,
• wherein, in a case that said engine control potion (35) identifies that a monochromatic toner is accommodated in each development unit, an image information sent from an external device is converted into monochromatic image data by the controller portion, and the monochromatic image data is stored in the controller portion, and
• a monochromatic development is performed based on the monochrome image data provided by the controller portion.

A method of forming an image by an image forming apparatus in which color information on a toner accommodated in a plurality of development units held in a development unit holder is identified by an engine control portion, and an image information sent from an external device is processed and stored by a controller portion, said development unit used in development is selected among said plurality of development units by said engine control portion by controlling said development unit holder, comprising the steps of:

• identifying the color information on the toner accommodated in each development unit by said engine control portion;
• and
• providing an image data for development by the controller portion;
• and
• performing a development using one of said development units;
• wherein, in a case that said engine control potion identifies that a monochromatic toner is accommodated in each development unit, an image information sent from an external device is converted into monochromatic image data by the controller portion, and the monochromatic image data is stored in the controller portion, and
• a monochromatic development is performed based on the monochrome image data provided by the controller portion.