Image forming apparatus

#The present invention relates to image forming apparatuses and, more particularly, to an image forming apparatus provided with a conveyance belt for conveying a recording medium.

#There is known, for example, an inkjet recording apparatus as an image forming apparatus such as a printer, a facsimile or a copy machine apparatus. An inkjet recording apparatus performs recording by discharging ink droplets from a recording head onto a recording medium such as a recording paper (hereinafter, simply referred to as a “paper” but material is not limited to a paper). The inkjet recording apparatus is capable of recording a fine image at a high speed with advantages such as a low running cost, a low noise and an easy color image recording using multi-color ink.

#In such an inkjet recording apparatus, it is required to increase a positional accuracy of landing positions of ink droplets on a paper so as to improve an image quality. There is known, such as disclosed in Japanese Laid-Open Patent Applications No. 4-201469, No. 9-254460 and No. 2000-25249, an inkjet recording apparatus that uniformly charges a conveyance belt to attract a paper by an electrostatic force to maintain a distance between a recording head and the paper constant, and to prevent an offset in a position of the paper by accurately controlling a paper feed, and to prevent a lift of the paper so as to prevent jamming and contamination of the paper due to a contact between the paper and the recording head.

#FIG. 1 is an illustrative side view of an image forming apparatus according to a first embodiment of the present invention;

#FIG. 2 is a plan view of a part of the image forming apparatus shown in FIG. 1;

#FIG. 3 is an illustration showing a layered structure of an example of a conveyance belt shown in FIG. 1;

#A description will now be given, with reference to the accompanying drawings, of embodiments according to the present invention. First, a description will be given, with reference to FIGS. 1 and 2, of an image forming apparatus according to a first embodiment of the present invention. FIG. 1 is an illustrative side view of the image forming apparatus. FIG. 2 is a plan view of a part of the image forming apparatus shown in FIG. 1.

#In the image forming apparatus shown in FIG. 1, a carriage 3 is slidably supported by a guide rod 1 and a guide rail 2 that bridge between left and right side plates (not shown in the figure) in a main scanning direction so that the carriage 3 is moved to scan in directions of arrows (the main scanning direction) in FIG. 2 by a main scanning motor via a timing belt being engaged with a drive pulley 6a and an idle pulley 6b. It should be noted that guide bushings (bearings) 3a are interposed between the carriage 3 and the guide rod 1, respectively.

#Four recording heads 7 which consist of liquid droplet discharge heads, which discharge ink droplets of yellow (Y), cyan (C), magenta (M) and black (Bk), are arranged so that a plurality of ink discharge ports are arranged in a direction perpendicular to the main scanning direction and ink droplet discharge direction is directed downward.