US 7,539,431 B2
Image forming apparatus and techniques for collecting toner
Takeshi Watanabe, Yokohama (Japan); Masashi Takahashi, Yokohama (Japan); and Mitsuaki Kouyama, Higashi-kurume (Japan)
Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan); and Toshiba Tec Kabushiki Kaisha, Tokyo (Japan)
Filed on Jun. 29, 2006, as Appl. No. 11/477,219.
Prior Publication US 2008/0002997 A1, Jan. 03, 2008
Int. Cl. G03G 15/00 (2006.01); G03G 21/12 (2006.01); G03G 21/00 (2006.01)
U.S. Cl. 399—71  [399/35; 399/354] 18 Claims
OG exemplary drawing
 
1. An image forming apparatus that performs image forming processing using plural image forming stations aligned along a specific direction and each transferring a toner image of a different color onto a transferred body moving in the specific direction, comprising:
a toner collection unit provided to at least one image forming station among the plural image forming stations at any of second and subsequent places from an upstream side in the specific direction and configured to collect toner adhering onto a photoconductor in the at least one image forming station near a toner image transfer position of the photoconductor on a downstream side, the toner collection unit being capable of switching between an inversely transferred toner collection mode to selectively collect inversely transferred toner having a charged polarity different from a polarity of toner used in the image forming station to which the toner collection unit is provided and a transfer residual toner collection mode to selectively collect transfer residual toner having a charged polarity same as the polarity of the toner used in the image forming station to which the toner collection unit is provided;
a judgment unit configured to judge which of the transfer residual toner and the inversely transfer toner needs to be collected according to specific information; and
a control unit configured to control the toner collection unit to execute the transfer residual toner collection mode when the judgment unit judges that the transfer residual toner needs to be collected, and to control the toner collection unit to execute the inversely transferred toner collection mode when the judgment unit judges that the inversely transferred toner needs to be collected.