IMAGE FORMING APPARATUS

PROBLEM TO BE SOLVED: To inexpensively detect the presence/absence of magnetic developer in a developer conveying path. SOLUTION: The image forming apparatus (U) is provided with: the developer conveying path (31) to which the magnetic developer is conveyed from developer supply parts (16 and 16'); radio antenna (34) arranged on one side and radio communication members (36 and 37) arranged on the other side while putting the developer conveying path (31) in between, which cannot perform radio communication in such a state that the magnetic developer is present in the developer conveying path (31) between the radio antenna (34) and the radio communication members (36 and 37), which however can perform the radio communication in such a state that the magnetic developer is not present therein; and developer presence/absence discrimination means (C6 and C6') for discriminating the presence/absence of the magnetic developer in the developer conveying path (31) according to the communication state between the radio antenna (34) and the radio communication members (36 and 37). COPYRIGHT: (C)2007,JPO&INPIT