Abstract: A sheet delivery mechanism designed to discharge successive sheets to different delivery positions includes offset rollers, an offset unit, an offsetting force generator and an offset unit swinging mechanism. The offset rollers is rotatably supported by the offset unit to discharge each sheet in a sheet transport direction. The offsetting force generator produces a driving force for shifting the offset unit back and forth along a direction perpendicular to the sheet transport direction between a reference position and offset positions. The offset unit swinging mechanism swings the offset unit about an axis parallel to rotary shafts of the offset rollers in such a manner that a sheet output direction in which the offset rollers eject each sheet varies to a direction pointing away from a sheet delivery tray when the offset unit is shifted along the direction perpendicular to the sheet transport direction by the offsetting force generator.

Abstract: When a print request has been made, a control portion confirms whether or not there is a request for post-processing by a paper post-processing portion (step S2) and the type of recording paper that is to be used (step S8). If there is a request for post-processing, then it is determined whether or not a discharge tray is extended (step S3). If the result shows that the discharge tray is retracted, then a message urging the discharge tray to be extended is displayed on a liquid crystal display panel (step S6), and if the discharge tray is extended, then print processing is started (step S4). Furthermore, if the size of recording paper that is to be used is longer than the discharge tray in a retracted state, then a message urging the discharge tray to be extended is displayed on the liquid crystal display panel (step S6), and if the discharge tray is extended, then print processing is started (step S4).

Abstract: The present invention provides a fixing device for fixing a toner image formed on paper by sandwiching the paper in a nip region between a heating roller and a pressing roller and pressing the paper while heating the paper to a fixing temperature. This fixing device includes a cleaning roller that is in contact with the pressing roller, and temperature control means that sets a temperature of the heating roller to a cleaning temperature that is higher than the fixing temperature.

Abstract: A heating device for heating a recording sheet. The heating device has a first heater located within a heating roller. The first heater has a heat distribution effective to form a low temperature region in an axially central portion of the heating roller and a high temperature region in each of axially opposite end portions of the heating roller. There is a second heater located within the heating roller that has a heat distribution effective to form a high temperature region in the axially central portion of the heating roller, a low temperature region in each of the opposite end portions of the heating roller, and a second-level high temperature region in each of axially opposite end portions of the high temperature region, the second-level high temperature region being lower in temperature than the high temperature region.

Abstract: A fixing device includes a fixing member in contact with an unfixed image constituted of developer T on one side of a recording material P; and a pressure member pressed against the fixing member. The fixing device fixes the unfixed image onto the recording material P by causing the recording material P, charged so as to have a same polarity as a polarity of the developer T, to pass through a gap between the fixing member and the pressure member. In the fixing device, an inflow current into the fixing member Ih is 0 when the recording material P passes through the gap between the fixing member and the pressure member. This securely restrains the developer on the recording material from electrostatically offset to the side of the fixing device, thereby maintaining the formation of high quality images.

Abstract: A heating device for heating a recording sheet includes: a first heater disposed within a heating roller and having a heat distribution characteristic to form a low temperature region in an axially central portion of the heating roller and a high temperature region in each of axially opposite end portions of the heating roller; and a second heater disposed within the heating roller and having a heat distribution characteristic to form a high temperature region in the axially central portion of the heating roller, a low temperature region in each of the opposite end portions of the heating roller, and a second-level high temperature region in each of axially opposite end portions of the high temperature region, the second-level high temperature region being lower in temperature than the high temperature region.

Abstract: A sheet delivery mechanism designed to discharge successive sheets to different delivery positions includes offset rollers, an offset unit, an offsetting force generator and an offset unit swinging mechanism. The offset rollers is rotatably supported by the offset unit to discharge each sheet in a sheet transport direction. The offsetting force generator produces a driving force for shifting the offset unit back and forth along a direction perpendicular to the sheet transport direction between a reference position and offset positions. The offset unit swinging mechanism swings the offset unit about an axis parallel to rotary shafts of the offset rollers in such a manner that a sheet output direction in which the offset rollers eject each sheet varies to a direction pointing away from a sheet delivery tray when the offset unit is shifted along the direction perpendicular to the sheet transport direction by the offsetting force generator.