Decurler and image forming apparatus

#This application claims priority to Japanese Patent Application No. 2013-273387 filed on Dec. 27, 2013, the entire contents of which are incorporated by reference herein.

#The present disclosure relates to decurlers and image forming apparatuses and particularly relates to a technique for adjusting a decurling force.

#Some of image forming apparatuses and like apparatuses are provided with a decurler operable to remove curl from a recording medium. The decurler includes an elastically deformable soft roller and a hard roller made harder than the soft roller and is configured to decurl a recording paper sheet at a nip region between both the rollers. There are also proposed, to ensure suitable decurling in response to changes over time and changes in a surrounding environment, a decurling mechanism in which the positions of the soft and hard rollers relative to a recording paper sheet passing through the nip region between them can be changed and a decurling mechanism in which the pressing force of a pair of rollers at the nip region between them can be changed.

#FIG. 1 is a front cross-sectional view showing the structure of an image forming apparatus according to one embodiment of the present disclosure.

#FIG. 2 is a perspective view showing a decurler.

#FIG. 3 is a perspective view showing a state where an upper housing is removed from the decurler.

#Hereinafter, a description will be given of a decurler and an image forming apparatus according to one embodiment of the present disclosure with reference to the drawings. FIG. 1 is a front cross-sectional view showing the structure of the image forming apparatus according to the one embodiment of the present disclosure.

#The image forming apparatus 1 according to the one embodiment of the present disclosure is a multifunction peripheral having multiple functions including, for example, a copy function, a print function, a scan function, and a facsimile function. The image forming apparatus 1 is made up so that an apparatus body 11 thereof includes an operating section 47, an image forming section 12, a fixing device 13, a paper feed section 14, a document feed section 6, a document reading section 5, and so on.

#In an image forming operation of the image forming apparatus 1, the image forming section 12 forms a toner image on a recording paper sheet P serving as a recording medium fed from the paper feed section 14, based on image data generated by the document reading operation, image data stored on the internal HDD or other image data. The image forming section 12 includes four image forming units 12M, 12C, 12Y, and 12Bk for different colors. Each image forming unit 12M, 12C, 12Y, 12Bk includes a photosensitive drum 121, a charging device 123, an exposure device 124, a developing device 122, and a primary transfer roller 126. The image forming section 12 further includes: an intermediate transfer belt 125 whose outer peripheral surface has an image carrying surface to which respective toner images formed by the four image forming units are to be transferred; and a secondary transfer roller 210 configured to transfer a multicolor toner image formed on the surface of the intermediate transfer belt 125 to a recording paper sheet P. The fixing device 13 is configured to fix the toner image on the recording paper sheet P by the application of heat and pressure using a heat roller and a pressure roller. The recording paper sheet P on which the multicolor image has been fixed by the completion of the fixing treatment is discharged to a paper output tray 151.