Abstract: An electrophotographic image forming apparatus in which overheating or burning of a heater caused by fabricating units whose specified supply voltages are different from each other is prevented. Power from a main unit is supplied to the heater, which is in a photosensitive drum in a drum unit, for heating the photosensitive drum so as to be maintained at a specified temperature, through a connecter disposed between the main unit and the drum unit. The connecter is comprised of parts which are respectively disposed in different positions, depending on the specified supply voltages. The respective positions of the parts vary, in relation to a reference position, in a direction around the rotation axis of the photosensitive drum which is rotated when the drum unit is installed in the main unit. When the specified supply voltage of the main unit is equal to that of the heater, the parts are fitted to each other, thereby making electrical connection.

Abstract: The object is to carry out developer feeding and toner supplement in a short time without scattering dust particles around, in view of the effectual use of natural resources and space saving. A developer cartridge is removably mounted on a developing unit body and also functions as a lid for closing a developer supply opening after developer has been released into the developing unit body. A toner cartridge includes a lid which can be inserted into and taken out of a toner cartridge body; a sealing member for sealing the toner release opening of the toner cartridge body, the leading edge of which is fixedly attached to the end of the lid on a side from which the lid is inserted; and a tab sheet one end of which is fixed to the middle position of the sealing member and the other end of which is temporarily affixed to the lid.