Developer Electric Field Conveyer, Developer Feeder, and Image Forming Apparatus

An image forming apparatus comprising:

• an electrostatic latent-image carrying body which has a latent-image forming surface formed in parallel with a predetermined main scanning direction and configured such that an electrostatic latent image in the form of an electric potential distribution is formed thereon, and which is configured such that the latent-image forming surface can move along a sub-scanning direction orthogonal to the main scanning direction;
• and
• a developer supply apparatus disposed to face the electrostatic latent-image carrying body, and configured to supply a developer in the form of fine particles onto the latent-image forming surface in a state in which the developer is charged, wherein the developer supply apparatus includes:
• a developer containing casing configured to be able to contain the developer therein and which includes an opening portion at a position facing the electrostatic latent-image carrying body;
• a plurality of transport electrodes arranged along the sub-scanning direction such that their longitudinal direction intersects with the sub-scanning direction, the transport electrodes being capable of transporting the developer in a predetermined developer transport direction when a traveling-wave voltage is applied to the transport electrodes;
• a flexible insulating substrate on which the transport electrodes are provided along the sub-scanning direction between margin areas, which are end portions thereof with respect to the sub-scanning direction, and which is accommodated within the developer containing casing such that a predetermined gap is formed between the insulating substrate and an inner wall surface of the developer containing casing;
• a substrate support member located in the developer containing casing, the substrate support member including an external surface extending in the main scanning direction and supports the insulating substrate thereon in such a manner that the transport electrodes face the latent-image forming surface via the opening portion with a predetermined developing gap formed therebetween;
• and
• tensilely fixing means for fixing the insulating substrate to the substrate support member in such a manner as to impart a predetermined tension along the sub-scanning direction to the insulating substrate.

A developer electric field transport apparatus configured to transport a charged developer in the form of fine particles along a predetermined developer transport direction by means of an electric field, the developer electric field transport apparatus comprising:

• a plurality of transport electrodes arranged along a moving direction of a developer carrying body having a developer carrying surface which carries a thin layer of the developer, the transport electrodes being configured such that their longitudinal direction intersects with the moving direction, and the transport electrodes can transport the developer in the predetermined developer transport direction when a traveling-wave voltage is applied to the transport electrodes;
• a flexible insulating substrate on which the transport electrodes are provided along the moving direction between margin areas which are end portions thereof with respect to the moving direction;
• a substrate support member including an external surface extending in the main scanning direction and supports the insulating substrate thereon;
• and
• tensilely fixing means for fixing the insulating substrate to the substrate support member in such a manner as to impart a predetermined tension along a direction perpendicular to the main scanning direction to the insulating substrate.