Electrophotographic single-component developing device

An electrophotographic single-component developing device comprising:

• a development roller;
• a first circulation passage juxtaposed to said development roller so as to extend in parallel to an axis of said development roller;
• a second circulation passage juxtaposed and extending parallel to said first circulation passage, said first circulation passage and said second circulation passage storing a single-component toner and communicating with each other at both opposite ends of said first circulation passage and said second circulation passage to define a recirculating path;
• a first spiral agitator formed from a wire, said first spiral agitator disposed in said first circulation passage;
• an accelerator rod mounted on said first spiral agitator;
• a second spiral agitator formed from a wire, said second spiral agitator disposed in said second circulation passage wherein said toner is circulated by said first spiral agitator and said second spiral agitator along said recirculating path and said toner is supplied to said development roller by said accelerator rod.

An electrophotographic single-component developing device comprising:

• a development roller;
• a first circulation passage juxtaposed to said development roller so as to extend in parallel to an axis of said development roller;
• a second circulation passage juxtaposed and extending parallel to said first circulation passage, said first circulation passage and said second circulation passage storing a single-component toner and communicating with each other at both opposite ends of the first circulation passage and the second circulation passage to define a recirculating path;
• a first spiral agitator formed from a wire, said first spiral agitator disposed in said first circulation passage;
• a second spiral agitator formed from a wire, said second spiral agitator disposed in said second circulation passage wherein said toner is circulated by said first spiral agitator and said second spiral agitator along said recirculating path and supplied to said development roller, wherein said first spiral agitator is directly connected at opposite ends thereof to a first pair of coaxial rotating shafts and said second spiral agitator is directly connected at opposite ends thereof to a second pair of coaxial rotating shafts, said first and second pairs of rotating shafts extending parallel to said axis of said development roller.