A developing device 31 includes three shielding members 20 that
divide
an inner space of the developing device 31 into a developing chamber 23
and toner hopper chambers 21. The shielding members 20 in predetermined
conditions prevent toner inside the developing chamber 23 from entering
the toner hopper chambers 21. When toner empty condition of the developing
chamber 23 is detected, the shielding member 20a is driven
to rotate so as to supply toner 22a into the developing chamber 23.
When the toner empty condition is detected for the second time, then the shielding
members 20a, 20b are driven to rotate for supplying toner
22b to the developing chamber 23. In this manner toner can
be supplied to the developing chamber 23 without allowing the toner returning
to the toner hopper chambers 21.
