Abstract: A sheet discharge device of the present invention includes discharge rollers configured to transport a sheet in a predetermined transport direction and to discharge the sheet to a discharge tray, and an upper discharge tray disposed above the discharge tray with a space being interposed therebetween. A bottom face of the upper discharge tray that faces the discharge tray includes a guide rib extending in an oblique direction inclined relative to the transport direction.

Abstract: A sheet discharge device of the present invention includes discharge rollers configured to transport a sheet in a predetermined transport direction and to discharge the sheet to a discharge tray, and an upper discharge tray disposed above the discharge tray with a space being interposed therebetween. A bottom face of the upper discharge tray that faces the discharge tray includes a guide rib extending in an oblique direction inclined relative to the transport direction.

Abstract: A sheet discharge device of the present invention includes discharge rollers configured to transport a sheet in a predetermined transport direction and to discharge the sheet to a discharge tray, and an upper discharge tray disposed above the discharge tray with a space being interposed therebetween. A bottom face of the upper discharge tray that faces the discharge tray includes a guide rib extending in an oblique direction inclined relative to the transport direction.

Abstract: A curl correcting apparatus includes rollers, a motor, and a clutch portion. The rollers are curl correction-use rollers which are arranged in parallel to each other in a pressure-contact state and which are different in hardness. The motor is a motor capable of rotating in forward and reverse directions relative to a correction-amount adjusting portion that changes and adjusts a distance to the rollers as a result of an eccentric cam that integrally rotates in accordance with a rotation amount of a rotation shaft, pressing against the rollers. The clutch portion transmits a rotary driving force of the motor to the rollers during the forward rotation and to a rotation shaft during the reverse rotation.

Abstract: A sheet discharge device of the present invention includes discharge rollers configured to transport a sheet in a predetermined transport direction and to discharge the sheet to a discharge tray, and an upper discharge tray disposed above the discharge tray with a space being interposed therebetween. A bottom face of the upper discharge tray that faces the discharge tray includes a guide rib extending in an oblique direction inclined relative to the transport direction.

Abstract: A curl correcting apparatus includes rollers, a motor, and a clutch portion. The rollers are curl correction-use rollers which are arranged in parallel to each other in a pressure-contact state and which are different in hardness. The motor is a motor capable of rotating in forward and reverse directions relative to a correction-amount adjusting portion that changes and adjusts a distance to the rollers as a result of an eccentric cam that integrally rotates in accordance with a rotation amount of a rotation shaft, pressing against the rollers. The clutch portion transmits a rotary driving force of the motor to the rollers during the forward rotation and to a rotation shaft during the reverse rotation.

Abstract: A fixing device includes a fixing roller, a single heating member that heats the fixing roller, a pressure roller, a first temperature detecting element that detects the temperature of the contact region, of the fixing roller, that comes into contact with the recording paper transported, and a second temperature detecting element that detects the temperature of the noncontact region of the fixing roller. The fixing device carries out energization control of the heating member based on the temperature detected by the first temperature detecting element and stops energization control of the heating member when the temperature detected by the second temperature detecting element reaches a prescribed temperature.

Abstract: A fixing device includes a fixing roller, a heating member, a pressure roller, a first temperature detecting element that detects a temperature of a contact region of the fixing roller that comes into contact with a paper, and a second temperature detecting element that detects a temperature of a noncontact region, and in which energization control of the heating member is carried out by the first one, and energization control is stopped when a temperature detected by the second reaches a prescribed temperature, the device including a conduction shutoff portion that, shuts off the energization where the temperature of the contact region has reached an upper limit, wherein, in which a center of the paper in an axial direction of the fixing roller has been aligned with a reference position of the fixing roller, the paper is transported, and the first one and the shutoff portion are placed symmetrically.

Abstract: One embodiment of an image forming apparatus according to the present invention is an image forming apparatus in which registration rollers are arranged immediately before an electrostatic latent bearing member and, after a carried paper is caused to temporarily stop by the registration rollers, carrying of the paper recommences with a timing enabling a leading edge of image information visualized on the electrostatic latent bearing member and a leading edge of the paper that has been stopped by the registration rollers to correspond, wherein, at a time of successive printing of multiple sheets, a carrying recommencement timing of an immediately subsequent paper is determined using information of a carrying recommencement timing of an immediately preceding carried paper.

Abstract: A pair of registration rollers are provided upstream in a paper transport path from an image forming position, and a paper transport position detection portion is provided upstream in the paper transport path from the pair of registration rollers. When consecutive print processing on a plurality of sheets of paper is performed, a paper transport position in the paper transport path is detected by the paper transport position detection portion for a sheet of paper that has been set in advance among the plurality of sheets of paper. A correction amount of a position for image writing to a photosensitive drum is determined based on the paper transport position, and correction of the image writing position is performed based on the correction amount.

Abstract: An apparatus for image formation comprises a fixing member, a pressing member, a heating member, a sensor, and a controller. The heating member heats at least one of the fixing and pressing members during a heating operation. The sensor senses the surface temperature of at least one of the fixing and pressing members. If the surface temperature sensed by the sensor exceeds a threshold temperature, the controller stops the heating operation of the heating member. If the sensed temperature drops below the threshold temperature, the controller starts the heating operation of the heating member. The controller includes a period measuring unit for measuring the switching period at which the controller switches the starting and stopping of the heating operation of the heating member. The controller restrains the heating of the fixing and pressing members if the switching period exceeds a reference time.

Abstract: According to an embodiment, an idler roller has an insertion through-hole through which a rotation shaft is inserted. Collar-shaped stopper portions are formed on the rotation shaft and are located on both left and right sides of the idler roller when the rotation shaft is inserted and provided at a normal position. Coil springs are attached between the stopper portions and base surfaces of concave groove portions of the idler roller. The idler roller is held at the normal position by biasing force of both the coil springs when paper is not seized. When paper is seized, the idler roller is moved in a lateral direction by elastic restoring force caused by a torsion phenomenon occurring in the paper. The idler roller returns to the normal position due to biasing force of both the coil springs after the paper has passed through the idler roller.

Abstract: An apparatus for image formation comprises a fixing member, a pressing member, a heating member, a sensor, and a controller. The heating member heats at least one of the fixing and pressing members during a heating operation. The sensor senses the surface temperature of at least one of the fixing and pressing members. If the surface temperature sensed by the sensor exceeds a threshold temperature, the controller stops the heating operation of the heating member. If the sensed temperature drops below the threshold temperature, the controller starts the heating operation of the heating member. The controller includes a period measuring unit for measuring the switching period at which the controller switches the starting and stopping of the heating operation of the heating member. The controller restrains the heating of the fixing and pressing members if the switching period exceeds a reference time.

Abstract: A guide member, which is constituted by an upper paper guide and a lower paper guide that form a paper transport path, is arranged between registration rollers and pre-registration rollers. At least one of the upper paper guide and the lower paper guide is supported swingably during printing operation.

Abstract: An image forming device includes a first carriage path for carrying paper stored in a paper feeding tray to a printer, there is a second carriage path for carrying paper stored in a second paper feeding tray to the printer. The first carriage path and the second carriage path individually carry a paper to the printer.

Abstract: An image forming apparatus includes a history storage portion for storing the usage history involving the number of prints of the image forming apparatus, and a processing time controller for changing the time of the pre-processing operation before or the time of the post-processing operation after a printing process of the printing portion, based on the stored usage history so as to exclude the influence of the unfixed developer on the printing process.

Abstract: An image forming apparatus includes a photoreceptor drum, a developing roller, a registration roller for positioning and conveying the paper and a drive controller for controlling the drive of the registration roller. The registration roller conveys the paper so that its leading end collides with the photoreceptor drum. The drive controller corrects the timing of driving the registration roller based on the detected eccentric variation of the peripheral surface of the photoreceptor drum and the rotational phase. The drive controller may acquire the eccentric variation as external data instead of detecting it.

Abstract: A pair of registration rollers are provided upstream in a paper transport path from an image forming position, and a paper transport position detection portion is provided upstream in the paper transport path from the pair of registration rollers. When consecutive print processing on a plurality of sheets of paper is performed, a paper transport position in the paper transport path is detected by the paper transport position detection portion for a sheet of paper that has been set in advance among the plurality of sheets of paper. A correction amount of a position for image writing to a photosensitive drum is determined based on the paper transport position, and correction of the image writing position is performed based on the correction amount.

Abstract: A guide member, which is constituted by an upper paper guide and a lower paper guide that form a paper transport path, is arranged between registration rollers and pre-registration rollers. At least one of the upper paper guide and the lower paper guide is supported swingably during printing operation.

Abstract: According to an embodiment, an idler roller has an insertion through-hole through which a rotation shaft is inserted. Collar-shaped stopper portions are formed on the rotation shaft and are located on both left and right sides of the idler roller when the rotation shaft is inserted and provided at a normal position. Coil springs are attached between the stopper portions and base surfaces of concave groove portions of the idler roller. The idler roller is held at the normal position by biasing force of both the coil springs when paper is not seized. When paper is seized, the idler roller is moved in a lateral direction by elastic restoring force caused by a torsion phenomenon occurring in the paper. The idler roller returns to the normal position due to biasing force of both the coil springs after the paper has passed through the idler roller.