Image forming apparatus including an image carrier, a charging member, a voltage applying part, a current measuring part and a controlling part

An image forming apparatus comprising:

• an image forming part including an image carrier carrying a toner image and a charging member electrically charging the image carrier;
• an apparatus main body housing the image forming part;
• an introducing part introducing air from outside the apparatus main body;
• a temperature sensor located inside the apparatus main body and arranged so as to detect a temperature of air introduced by the introducing part;
• a voltage applying part applying voltage to the charging member;
• a current measuring part measuring current flowing into the charging member;
• and
• a controlling part carrying out a dew condensation avoiding operation in order to avoid a dew condensation of the image forming part under conditions that an increase quantity of the detected temperature of the temperature sensor, when air from outside the apparatus main body is introduced by the introducing part, is equal to or more than a first predetermined threshold value and that an increase quantity of the current measured by the current measuring part, when a predetermined voltage is applied to the charging member by the voltage applying part, is equal to or more than a second predetermined threshold value,
• wherein inside the apparatus main body, a first duct extending upward from an introducing part's side of the apparatus main body where the introducing part is located to an image forming part's side of the apparatus main body where the image forming part is located and a second duct extending downward from the introducing part's side to a side of the apparatus main body, which is different from the image forming part's side are arranged, and the temperature sensor is arranged in the second duct, and
• an external member is arranged in a horizontal end part of the apparatus main body, and the introducing part and the temperature sensor are located at an internal face side of the external member.