Electrophotographic image forming apparatus equipped with toner conveyance device

An electrophotographic image forming apparatus comprising:

• (a) an image forming section for forming a toner image on an image carrier and transferring the formed toner image onto a recording material;
• (b) a recording material storing section for storing recording materials;
• (c) a sheet feeding and conveying section provided sideward of the recording material storing section for supplying a recording material from the recording material storing section to the image forming section;
• (d) a toner reservoir section provided on a side opposite to the sheet feeding and conveying section with respect to the recording material storing section, for storing toner to be supplied to a developing device of the image forming section;
• (e) a toner separation section provided upward of the developing device to separate the toner;
• (f) a supply pipe for interconnecting the toner reservoir section and the toner separation section to supply the toner;
• (g) a collection pipe for interconnecting the toner reservoir section and the toner separation section to collect the toner;
• (h) a first fluid conveyance device provided on the supply pipe between the toner reservoir section and the toner separation section for conveying a supply fluid;
• and
• (i) a second fluid conveyance device provided on the collection pipe between the toner reservoir section and the toner separation section for conveying a collection fluid,
• wherein the supply pipe and the collection pipe are provided on a rear side of the apparatus, and between the toner reservoir section and the toner separation section in a straight line.

An electrophotographic image forming apparatus comprising:

• (a) an image forming section for forming a toner image on an image carrier and transferring the formed toner image onto a recording material;
• (b) a recording material storing section for storing recording materials;
• (c) a sheet feeding and conveying section provided sideward of the recording material storing section for supplying a recording material from the recording material storing section to the image forming section;
• (d) a toner reservoir section provided on a side opposite to the sheet feeding and conveying section with respect to the recording material storing section, for storing toner to be supplied to a developing device of the image forming section;
• (e) a toner separation section provided upward of the developing device to separate the toner;
• (f) a supply pipe for interconnecting the toner reservoir section and the toner separation section to supply the toner;
• (g) a collection pipe for interconnecting the toner reservoir section and the toner separation section to collect the toner;
• (h) a first fluid conveyance device provided on the supply pipe between the toner reservoir section and the toner separation section for conveying a supply fluid;
• and
• (i) a second fluid conveyance device provided on the collection pipe between the toner reservoir section and the toner separation section for conveying a collection fluid,
• wherein the collection pipe comprises a first vertical pipe section extending upward from the toner reservoir section and a first horizontal pipe section extending horizontally to reach the toner separation section, and the second fluid conveyance device is provided at a coupling point of the first vertical pipe section and the first horizontal pipe section.