JP2000122365A5 - - Google Patents

Description

[0008]
SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the first to thirteenth inventions according to the present invention is to provide a print job on a plurality of image carriers each of which is different for each color component by a print job. The density of the image formed in each is detected, and to any one of the one image carrier or the plurality of the image carriers according to each addition value of the detected image densities, to a developing device for each color. By controlling the residual developer collecting operation of the image forming apparatus, it is possible to limit the residual developer collecting operation for an unnecessary image carrier, minimize the decrease in productivity, and suppress the deterioration of the image carrier. An object of the present invention is to provide a control method for a forming apparatus and an image forming apparatus.

[0009]
[Means for Solving the Problems]
According to a first aspect of the present invention, a latent image formed on a plurality of image carriers (photosensitive drums 342, 343, 344, and 345 shown in FIG. 1) which differ from one another for each color component by a print job is classified by color. Image forming means for each color (yellow shown in FIG. 1) which develops with a developing device (developing units 322, 325, 328, and 331 shown in FIG. 1) and transfers each to a fed recording medium to form a multicolor image (Y) an image forming unit 317, a magenta (M) image forming unit 318, a cyan (C) image forming unit 319, and a black (K) image forming unit 320). Collecting means (charging units 321, 324, 327, 330, developing units 322, 325, 328, 331 shown in FIG. 1) for each color collected in the developing unit, and the density of an image formed on each of the image carriers. Detect each A plurality of detecting means (video signal counting units 220 to 223 shown in FIG. 4) and any one of the image carriers by each of the collecting means according to each added value of each image density detected by each of the detecting means (Photosensitive drum 342 shown in FIG. 1) or a control means (image processing unit shown in FIG. 1) for controlling the residual developer collecting operation for any one of the plurality of image carriers (photosensitive drums 342, 343 and 344 shown in FIG. 1). 312 is controlled based on a program stored in the ROM).

[0016]
In an eighth aspect according to the present invention, the control means (a CPU (not shown) in the image processing unit 312 shown in FIG. 1) performs a residual developer collecting operation when a print job is interrupted, and the charging device takes in the developing agent once. After the agent is discharged onto the image carrier, the sleeve is removed in a state where the magnetic field generating means is not driven (only the AC bias for the chargers 321, 324, 327, and 330 shown in FIG. 1 is "OFF"). The charging device is controlled so as to perform a process of discharging the developer by rotating the charging device.

[0021]
According to a thirteenth aspect of the present invention, a latent image formed on a plurality of image carriers each of which is different for each color component by a print job is developed by a developing device for each color and transferred to a fed recording medium. A multi-color image forming means for forming a multi-color image, and a collecting means for each color for collecting the residual developer on each image carrier into each of the developing devices. A plurality of detection steps (step (1) in FIG. 6 and step (1) in FIG. 7) for respectively detecting the density of an image formed on each of the image carriers, and adding each of the detected image densities. A recovery step (steps (2) and (3) in FIG. 6) for executing a residual developer recovery operation on the one or more image carriers by the respective recovery means according to the values. Step 7 (2) (3) 8 Step (1) to (3)) and those having a.

[0114]
【The invention's effect】
As described above, according to the first and ninth to twelfth aspects of the present invention, the density of an image formed on a plurality of image carriers different from each other for each color component by a print job is adjusted to a plurality of levels. The detecting means respectively detects, and according to each addition value of each image density detected by each of the detecting means, the control means controls the one or more of the plurality of image carriers for each of the image carriers by color. Since the operation of recovering the residual developer to the developing device is controlled, the operation of recovering the residual developer to unnecessary image carriers is limited, and any one of the image carriers or the image carrier at a timing corresponding to the image density of each image carrier is controlled. By performing the residual developer collecting operation on any one of the plurality of image carriers, the reduction in productivity can be minimized, and the deterioration of the image carriers can be suppressed.

[0116]
According to the eighth aspect, the control means performs a residual developer collecting operation when a print job is interrupted, discharges the developer once taken in by the charger onto the image carrier, and further controls the magnetic field generating means. The charging device is controlled so as to perform a process of discharging the developer by rotating the sleeve in a state in which the developer is not driven, so that even in the residual developer collecting operation when the print job is interrupted, a high image density is obtained when the developer collecting operation is performed. The developer formed with the image and taken into the charger is sufficiently discharged to prevent the developer from mixing with the low-resistance carrier forming the dielectric brush in the charger, thereby maintaining the charging performance.

[0117]
Latent images formed on a plurality of image carriers, each of which is different for each color component by a print job, are developed by a developing unit for each color and transferred to a recording medium to be fed, thereby forming a multicolor image. In the method for controlling an image forming apparatus, the image forming unit includes: a plurality of image forming units; and a collecting unit for each color that collects the residual developer on each of the image carriers into each of the developing units. The operation of collecting the residual developer on any one of the image carriers or the plurality of the image carriers by each of the collecting units according to each of the detected image densities and the sum of the detected image densities. Is performed, the residual developer collecting operation for the unnecessary image carriers is restricted, and the residual of any one image carrier or any of the plurality of image carriers at a timing corresponding to the image density of each image carrier. Present Agent performs recovery operation, together with minimizing lowering of productivity, it is possible to suppress degradation of the image carrier.

Claims (3)

Latent images formed on a plurality of image carriers, each of which is different for each color component by a print job, are developed by a developing unit for each color and transferred to a recording medium to be fed, thereby forming a multicolor image. Image forming means;
Collecting means for each color for collecting the residual developer on each of the image carriers into each of the developing devices; a plurality of detecting means for respectively detecting the density of an image formed on each of the image carriers; control means for controlling the residual developer recovery operation for said any one image bearing member or said one plurality of image bearing members according to prior Symbol respective collecting means in response to the added value of the image density detected by the detection means An image forming apparatus comprising: Wherein said control means performs residual developer recovery operation when a print job interrupted, the charging device after discharging on the image bearing member is once taken developer, wherein in a state that does not further drive the magnetic field generating means 5. The image forming apparatus according to claim 4, wherein the charger is controlled to perform a process of discharging a developer by rotating a sleeve. Latent images formed on a plurality of image carriers, each of which is different for each color component by a print job, are developed by a developing unit for each color and transferred to a recording medium to be fed, thereby forming a multicolor image. A method for controlling an image forming apparatus, comprising: an image forming unit; and a collecting unit for each color for collecting the residual developer on each of the image carriers into each of the developing units.
A plurality of detection step and said any one of the image carrier by the pre-Symbol respective collecting means in response to the added value of the image density are detected to detect the density of an image to be formed on the respective image carriers, respectively Or a recovery step of performing a residual developer recovery operation on any one of the plurality of image carriers,
A method for controlling an image forming apparatus, comprising: