Image forming apparatus

An image forming apparatus comprising:

• an image bearer movable in a moving direction at multiple linear speeds;
• an image forming unit contacting the image bearer to form one or more patterns on the image bearer with toner;
• a transferor contacting the image bearer to form a transfer nip;
• a cleaner contacting the image bearer to clean the one or more patterns on the image bearer;
• and
• circuitry configured to
• set a linear speed from among one of the multiple linear speeds as a set linear speed,
• determine a number of the one or more patterns based on the set linear speed, and
• control the image forming unit to
• form one pattern of the one or more patterns on the image bearer, or
• form multiple patterns of the one or more patterns on the image bearer at a predetermined interval in the moving direction,
• wherein each of the one or more patterns has a length in the moving direction shorter than a circumferential length of the transferor, and the predetermined interval in the moving direction is longer than the circumferential length of the transferor.

An image forming apparatus comprising:

• an image bearer movable in a moving direction at multiple linear speeds;
• an image forming unit contacting the image bearer to form one or more patterns on the image bearer with toner;
• a transferor contacting the image bearer to form a transfer nip;
• a cleaner contacting the image bearer to clean the one or more patterns on the image bearer;
• circuitry configured to
• set a linear speed from among the multiple linear speeds as a set linear speed,
• determine a number of the one or more patterns based on the set linear speed, and
• control the image forming unit to
• form one pattern of the one or more patterns on the image bearer, or
• form multiple patterns of the one or more patterns on the image bearer at a predetermined interval in the moving direction;
• and
• a power source configured to output a transfer bias to transfer the toner from the image bearer to a recording medium and a reverse polarity bias having a polarity opposite to a polarity of the transfer bias,
• wherein the circuitry is further configured to
• control the power source to perform a cleaning operation that moves a substance adhered to the transferor to the image bearer to clean the image bearer, and
• control the image forming unit and the power source such that the one or more patterns pass through the transfer nip while the power source outputs the reverse polarity bias.