摘要:
PROBLEM TO BE SOLVED: To provide an image forming apparatus that accurately detects phase information on unevenness in image density and corrects the image density, while preventing the occurrence of abnormal images, so as to appropriately reduce the unevenness in density.SOLUTION: A copier 100 includes: a photoreceptor drum 2; a photoreceptor home position sensor; a developing unit 5; a primary transfer roller 6 that transfers a toner image to an intermediate transfer belt 1; a toner image detection sensor 30 that detects the density of the image on the intermediate transfer belt 1; and a control unit that forms a predetermined image pattern, acquires a toner adhesion amount detection signal detected by the toner image detection sensor 30 and a rotation position detection signal, and determines image formation conditions on the basis of data on the acquired detection signals. The photoreceptor drum 2 and the intermediate transfer belt 1 have a different linear velocity from each other during image formation. When the control unit that is image formation condition determination means performs control to correct unevenness in image density, performs control to cause the photoreceptor drum 2 and the intermediate transfer belt 1 to have the same linear velocity.
摘要:
PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of reducing periodic unevenness in image density corresponding to a rotation period of a rotating body over time used in toner image formation even at the occurrence of deterioration over time of the surface of the rotating body, while achieving a reduction in waiting time for correction of a control target value of image forming conditions based on a detection result of a toner image of an image pattern for control.SOLUTION: An image forming apparatus forms, during image forming operation of an output target image, a toner image of an image pattern for control in a non-image formation area on an intermediate transfer belt 1 where a toner image of the output target image is not formed, and corrects a control target value of image forming conditions such as developing bias and exposure power on the basis of a detection result of the density of the toner image.
摘要:
PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of accurately detecting failures in an image forming step performed on the downstream side of a toner image detecting means in the toner image conveying direction, and also, suppressing consumption of a recording medium and obtaining good images over a long period of time. SOLUTION: In the image forming apparatus, a toner image detecting sensor 30 for detecting the toner image before being transferred onto a recording paper 20 and a fixed image detecting sensor 31 for detecting the toner image after being secondarily transferred and fixed on the recording paper 20 are positioned to align with each other in the main scanning corresponding direction. The image forming apparatus includes a first image adjusting mode to adjust the image on the basis of only a result of detection by the toner image detecting sensor 30 without transferring a test pattern onto the recording paper 20, and a second image adjusting mode to adjust the image by transferring the test pattern onto the recording paper 20 and on the basis of both a result of detection by the toner image detecting sensor 30 and a result of detection by the fixed image detecting sensor 31. COPYRIGHT: (C)2011,JPO&INPIT
摘要:
PROBLEM TO BE SOLVED: To efficiently execute the suppression control for toner concentration variation. SOLUTION: The image forming apparatus includes: a developing unit for developing a latent image, formed on an image carrier, with developer containing toner; a toner supply section 202 for supplying toner to developer; a sensor 201 for measuring the value of a parameter that may affect developer agitation; a determining section 211 for determining a division unit in accordance with variation in the measured value, the division unit being used to divide image information at least in a main scanning direction or sub-scanning direction; a pixel capturing section 212 for capturing image information per determined division unit; a supply quantity calculating section 213 for calculating a quantity of toner supplied so as to prevent the toner density of the developer from changing with time, which results from developing a latent image in accordance with image information; and a supply control section 214 for controlling the toner supply section 202 so as to supply the calculated quantity of toner. COPYRIGHT: (C)2011,JPO&INPIT
摘要:
PROBLEM TO BE SOLVED: To provide a recording-body transport failure predicting method, capable of predicting the transport failure of a recording body in an image forming apparatus, such as paper jam prior to occurrence, and carrying out a necessary measure, such as maintenance before the occurrence of transport failure; a fixing device which is capable of predicting the occurrence of jam at fixing and carrying out a measure, such as maintenance, in advance, and to provide an image forming apparatus that uses them. SOLUTION: By providing a separating claw contact sensor 210, which detects the contact of recording paper P with a separating claw 203 as a locus abnormality-detecting means to a fixing device 25, locus abnormality in which the recording paper P, after passing through a nip part N shows a locus which is different from normal locus is detected, so that the occurrence of separation abnormality at a separation part α can be detected. In addition, by detecting the occurrence of separation abnormality of the recording paper P at the separation part α, the occurrence of a jamming can be predicted; a maintenance, such as, component replacement or repair can be carried out before the occurrence of jam; and loss of time of a user can be reduced. COPYRIGHT: (C)2011,JPO&INPIT
摘要:
PROBLEM TO BE SOLVED: To provide a developing device capable of reducing difference of agent density (bulk density) on the detection surface of a toner concentration sensor in a stirring operation while preventing erroneous detection by staying of developer on the detection surface. SOLUTION: The developing device 40Y using two-component developer includes: a conveyance screw 47Y arranged in a developer storage part 43Y2 constituted of a casing 43Y; a concentration detection surface 430 provided facing the rotation locus of the conveyance screw 47Y; and the concentration sensor 48Y. A detection surface stirring member 200 capable of stirring the developer by sliding the detection surface 430 is provided at a position facing the detection surface 430 in the axial direction of the conveyance screw 47Y, wherein the member 200 is formed into a rectangular wave shape, and includes an elastic sheet 200B which deflects and deforms while being brought into contact with the detection surface at a projected part. COPYRIGHT: (C)2010,JPO&INPIT
摘要:
PROBLEM TO BE SOLVED: To maintain the quality of a final output image by: comprehending the adverse effects of a paper transfer (secondary transfer) step and a fixing step on the final output image on recording paper; and performing a feedback control to these steps if necessary. SOLUTION: The image forming apparatus includes: a toner image detection sensor 30 for detecting a toner image not transferred to the surface of recording paper 20 in a position P1 or P2; and a fixed image detection sensor 31 for detecting a toner image secondarily transferred to the surface of the recording paper 20. The toner image detection sensor 30 and the fixed image detection sensor 31 are aligned in a direction corresponding to main scan which intersects the direction of conveyance of the recording paper 20 at right angle. To compare the output values of both the sensors, measurement data of sensor heads in the same position in the direction corresponding to the main scan are compared. Thus, if nonuniform image density is caused as a result of the second transfer step to the fixing step, the adverse effects of them are correctly comprehended. COPYRIGHT: (C)2010,JPO&INPIT