JP2007033829A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of reducing a productivity decrease resulting from setting up of marking, by restraining a period of image formation interruption even when carrying out post-processing. <P>SOLUTION: It is determined whether a finisher is performing a set ejection operation or not (S104). If it is performing the set ejection operation, it is determined whether the mode of the finisher has been switched or not (S106). If the mode has been switched, a determination is made whether the number of sheets subjected to image formation is within a predetermined number or not (108). If the number is within the predetermined number, marking is set up (S112). Next, it is determined whether the operation of the finisher and the setting up of making have been finished or not (S114). If they have been finished, an images is formed on paper sheet (S116), and the paper sheet is conveyed to the finisher. Subsequently, a determination is made whether an image forming job has been finished or not (S118). If it has been finished, the process ends. If the determination is negative, the process proceeds to S104. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus, and in particular, an image forming unit including an image forming unit that forms an image on a recording sheet and a post-processing unit that performs post-processing on the recording sheet on which the image is formed. Relates to the device.

  In the image forming apparatus, density adjustment, color registration adjustment and the like (hereinafter referred to as “marking setup”) are executed every time a predetermined number of images are formed when the power is turned on.

  However, since the image formation is interrupted during the marking setup, there is a downtime during the marking setup.

On the other hand, a technique for reducing downtime by executing a marking setup during warm-up of a fixing device of an image forming apparatus has been proposed (see Patent Document 1).
JP-A-8-95460

  However, for example, in a fixing mechanism that fixes an image on a recording sheet, the temperature in the fixing mechanism differs after a large number of continuous processes and after a small number of processes are intermittently performed. It can happen. When the temperature in the fixing mechanism is different, the density of the formed image is often different. In such a case, it is necessary to adjust the image quality for each reference number. On the other hand, when post-processing such as stapling, punch punching, and offset operation is performed, the post-processing is performed every time the job is completed.

  In the case of the above-described situation, with the technique described in Patent Document 1, it is possible that the marking setup and post-processing of the image forming apparatus are executed separately. Then, the time during which image formation is interrupted is accumulated, and the productivity is significantly reduced.

  In consideration of the above facts, the present invention is to obtain an image forming apparatus capable of suppressing the time during which image formation is interrupted by execution of marking setup even when post-processing is performed, and reducing a decrease in productivity. Objective.

  The present invention provides an image forming apparatus that includes an image forming unit that forms an image on a recording sheet, and a post-processing unit that performs post-processing on the image-formed recording sheet. The image quality adjusting unit that executes the image quality adjustment to stabilize the image quality of the image, which is executed for each reference processing number set in advance, is synchronized with the time when the post-processing unit operates and the time when the image quality adjustment is performed. And an instruction means for instructing the image quality adjusting means to execute the image quality adjustment regardless of the arrival of the reference processing number.

  According to the present invention, when the image forming unit forms an image on the recording paper, the post-processing unit performs post-processing on the recording paper on which the image is formed.

  In the image forming unit, the image quality of the image changes due to the image formation. On the other hand, the image quality adjustment means performs image quality adjustment for stabilizing the image quality of the image for each preset reference processing number. Here, the number of sheets is, for example, the number of sheets converted to A4 size. In general, image formation is interrupted during image quality adjustment.

  On the other hand, on the basis of the processing status of the post-processing unit, the instruction unit controls the image quality adjustment unit regardless of the arrival of the reference processing number so that the time when the post-processing unit operates and the time when image quality adjustment is performed are synchronized. Instructs execution of the image quality adjustment.

  Generally, image quality adjustment in the image forming unit is executed for each predetermined reference processing number of sheets. In contrast, post-processing performed by the post-processing unit is performed for each image forming job. In other words, conventionally, there has been no correlation between the execution timing of image quality adjustment and post-processing. For this reason, for example, image formation is interrupted when the image forming job is completed and post-processing is performed, and immediately after that, the number of processed sheets reaches the reference number of processed sheets, and image formation is interrupted when image quality adjustment is executed. A situation like this could happen. Such a situation is very inefficient.

  In contrast, the present invention suppresses the time during which image formation is interrupted by performing image quality adjustment when the post-processing apparatus operates regardless of the arrival of the standard processing number of sheets, and production by executing image quality adjustment. Deterioration can be reduced.

  Further, in the present invention, the instruction from the instruction means is valid when the number of processed sheets is a predetermined number less than the preset reference number of processed sheets.

  The predetermined number is 10% to 20%, preferably 10% of the reference processing number. If it exceeds 20%, the number of image quality adjustments will increase too much and the processing efficiency will decrease. Further, if it is less than 10%, there is no point in processing at an early stage.

  Further, the present invention is characterized in that the difference between the number of processed images when image quality adjustment is executed by the instruction means and the preset reference number of processed images is carried forward to the reference number of processed image adjustments to be performed next. To do.

  In the present invention, the operation of the post-processing unit includes actual post-processing performed by the post-processing unit and setting change operation of the post-processing performed by the post-processing unit.

  The interruption of image formation due to the operation of the post-processing unit occurs not only when the post-processing unit performs the actual post-processing, but also when the post-processing setting change operation is performed. Therefore, the present invention instructs the image quality adjustment means to perform image quality adjustment so that the image quality adjustment is synchronized not only when performing actual post-processing but also when performing post-setting setting change operation. By doing this, it is possible to further suppress the time during which image formation is interrupted, and to reduce productivity.

  As described above, the present invention obtains an image forming apparatus capable of suppressing the time during which image formation is interrupted by executing the marking setup even when post-processing is performed, and reducing the reduction in productivity. Has an excellent effect.

  An example of an embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a schematic configuration of an image forming apparatus 10 applied to the present embodiment. The image forming apparatus 10 applied to the present embodiment forms and outputs an image according to image data while conveying an image recording sheet (hereinafter simply referred to as “sheet”) P.

  The image forming apparatus 10 is formed by an IOT 12 and a finisher 14. The IOT 12 forms a single image forming mechanism that forms an image according to image data on the sheet P alone. In the image forming apparatus 10 applied to the present embodiment, the IOT 12 applies to the sheet P on which image formation has been completed in the IOT 12. A finisher 14 capable of various post-processing (hereinafter, post-processing changing operation is referred to as “mode setting change”) is provided. Post-processing of the finisher 14 includes stapling, offset, ejecting operation, and the like.

  In the image forming apparatus 10, the IOT 12 is connected to an image creating apparatus such as a personal computer or a workstation via various networks, and forms an image on the paper P based on image data input from the image creating apparatus. In addition, a scanner (image reading device) having an automatic document feeding function or the like is connected to the IOT 12, and image data generated by reading a document image by the scanner is input. Also good.

  The IOT 12 of the image forming apparatus 10 is provided with a paper feed unit 16 on which paper P to be supplied to the IOT 12 is loaded.

  The paper feed unit 16 is provided with a plurality of paper feed trays 18 each of which can accommodate and stack paper P. The uppermost paper P is taken out from the paper feed tray 18 and the taken paper P is conveyed. And send it to the IOT 12.

  The image forming apparatus 10 can form images on various sizes of paper P by accommodating different sizes of paper P in the paper feed tray 18.

  Further, the IOT 12 is provided with an endless transfer belt 20 serving as an intermediate transfer member, and facing the transfer belt 20, Y (yellow), M (magenta), C (cyan), and K (black). Development units 22 (development units 22Y, 22M, 22C, and 22K) are arranged. Each of the developing units 22 is loaded with a drum cartridge 26 (26Y, 26M, 26C, 26K) including a photosensitive drum 24 (24Y, 24M, 24C, 24K) that contacts the transfer belt 20.

  The IOT 12 generates image data (raster data) of each color component of Y, M, C, and K as image data, and the photosensitive drums 24Y, 24M, and 24C based on the image data of each color of Y, M, C, and K. , 24K are exposed to form toner images of the respective colors, and the toner images formed on the photosensitive drums 24Y, 24M, 24C, and 24K are superimposed on the transfer belt 20 and transferred. When forming a color image, four colors of CMYK are used. However, when forming a monochrome image such as a black and white image, only a toner image of a necessary color is formed on the photosensitive drum 24 and is applied to the transfer belt 20. Transcript.

  The IOT 12 is provided with a pair of a transfer roller 28 and a roller (bias transfer roller) 30 on the conveyance path side of the paper P. The transfer belt 20 is wound around the transfer roller 28 and sandwiched between the transfer roller 28 and the roller 30. Has been.

  The IOT 12 is provided with a fixing unit 32, and a fixing cartridge 36 including a pair of fixing rollers 34 is loaded in the fixing unit 32.

  The paper P fed from the paper feed unit 16 is superimposed on the transfer belt 20 onto which the toner image has been transferred, and is sandwiched between the transfer roller 28 and the roller 30, whereby the toner image on the transfer belt 20 is transferred. By being sent to the fixing unit 32, it is sandwiched between the fixing rollers 34 and heated while being pressurized. As a result, an image corresponding to the image data is formed on the paper P.

  A reversing unit 38 is provided below the fixing unit 32, and a circulation conveyance path for returning the paper P from the reversing unit 38 to the paper feeding side (the paper feeding unit 16 side) to the IOT 12 is formed. .

  In the IOT 12, when double-sided printing is set, the paper P on which the first image is formed on one side is sent to the reversing unit 38, and the reversing unit 38 reverses the transport direction of the paper P and passes through the circulation transport path. By returning to the paper feeding side of the IOT 12, the second side image is formed on the other side of the paper P.

  In other words, the image forming apparatus 10 can form an image in a color mode or a single color mode or an image in a single-sided / double-sided mode on a paper P having an arbitrary size. Such an IOT 12 can apply a general configuration for forming an image on the paper P by an electrophotographic process.

  The paper P on which an image is formed is sent from the IOT 12 to the finisher 14.

  The finisher 14 is provided with paper discharge trays 40A and 40B, and a conveyance path for the paper P toward the paper discharge trays 40A and 40B is formed. The paper P is conveyed toward the paper discharge tray 40A, and is discharged and collected on the paper discharge tray 40A with the image forming surface (second image forming surface in double-sided printing) facing upward. . Further, the paper P is conveyed toward the paper discharge tray 40B, and is discharged and collected on the paper discharge tray 40B with the image forming surface directed downward.

  Further, the finisher 14 is provided with a booklet creation unit 42, a staple unit 44, and a folding unit 46. In the booklet creation unit 42, when the paper P is fed, the set number of the paper P is overlapped and saddle-stitched, and then folded into two, for example, to be stacked in the stocker 42A. The booklet creation unit 42 is also used for Z-folding the paper P.

  When the paper P is fed, the stapling unit 44 stacks the paper P by a set number, staples a predetermined position of the peripheral edge, and discharges the paper P to the tray 44A. In the staple unit 44, if punching processing for punch holes is set, punch holes are punched at predetermined positions on the paper P and discharged to the tray 44A.

  When the paper P is fed, the folding unit 46 folds the paper P in half and discharges it to the tray 46A. As a result, the paper P is folded and stacked on the tray 46A.

  That is, the finisher 14 has a booklet creation function, a stapling function, and a folding function as examples of the post-processing function. The finisher 14 is an example of post-processing that can be applied in the image forming apparatus 10, and does not limit the configuration of the post-processing. The finisher 14 can be provided with any post-processing function. .

  For example, as shown in FIG. 1, the IOT 12 is provided with an operation panel 48 provided with a monitor for displaying various types of information including messages and a keyboard for inputting various types of information on the top surface.

  Next, with reference to FIG. 2, the main configuration of the electrical system of the image forming apparatus 10 according to the present embodiment will be described.

  The image forming apparatus 10 is provided with a main controller 50 that controls the operation. The main controller 50 includes a CPU, and the main controller 50 controls the operation of the finisher 14 together with the operation of the IOT 12.

  The main controller 50 is connected to a network line with an external host computer (not shown) so that image data is input.

  When the image data is input, the main controller 50, for example, analyzes the print instruction information included in the image data and the image data, and converts them into a format suitable for the image forming apparatus (for example, bitmap data). Image data is sent to the IOT control unit 52.

  The IOT control unit 52 synchronously controls each of the drive system control unit 54, the charging control unit 56, the exposure control unit 58, the development control unit 60, the transfer control unit 62, and the fixing control unit 64 based on the input image data. Then, image formation is executed.

  The main controller 50 is connected to a color registration detection sensor 66 that detects a color registration pattern. The color registration pattern is a color shift that occurs when the print head assembly position accuracy of each color, ejection timing accuracy, insufficient conveyance belt (not shown) conveyance accuracy, environment, installation status, machine temperature, etc. In order to prevent color misalignment, it is formed on the conveyor belt or paper P to detect color misregistration. The color registration pattern is mainly composed of a pattern in which lines of each color are formed at regular intervals, and the shape thereof is not limited as long as color misregistration can be detected. The color registration detection sensor 66 may measure the pattern interval with a CCD sensor, or may measure the reflection timing of each color line of the color registration pattern with an optical sensor. The amount is to be detected. A signal from the color registration detection sensor 66 is transmitted to the main controller 50.

  Further, the main controller 50 is connected to a density detection sensor 68 that detects the density of the density detection pattern. The concentration detection sensor 68 is configured to transmit a signal to the main controller 50.

  The density detection pattern is formed on the transport belt or the paper P so that a change in density on the transport belt or the paper P can be detected.

  By the way, when the marking setup is executed, the positional deviation adjustment by the detection of the color registration detection sensor 66 and the density adjustment by the detection of the density detection sensor 68 are performed. In the present embodiment, only the positional deviation adjustment and the density adjustment are described as the marking setup. However, the present invention is not limited to these, and various adjustments such as adjustment of the intensity of exposure and adjustment of the current applied to the transfer roller 28 are provided. Includes adjustment processing.

  The main controller 50 is also connected to a print counter 70 that measures the number of sheets on which image formation has been performed. When the print counter 70 measures a predetermined reference processing number (for example, 1,000 sheets for A4 size), the print counter 70 outputs to the main controller 50 that the number has reached the reference processing number. ing. When the main controller 50 receives the output of the print counter 70, the main controller 50 instructs the IOT control unit 52 to execute the marking setup. The main controller 50 resets the number of sheets measured by the print counter 70 after instructing execution of marking setup.

  Further, the main controller 50 is also connected to a finisher processing control unit 72 that controls the operation of the finisher 14 and a monitoring unit 73 that monitors the operation of the finisher 14. The monitoring unit 73 outputs monitoring information of the finisher 14 controlled by the finisher processing control unit 72 to the main controller 50.

  The finisher processing control unit 72 sets the mode of the finisher 14 and the set discharge controller 74 that controls post-processing (hereinafter referred to as “set discharge operation”) based on the setting of the print job of the paper P on which the image is formed. It is connected to a finisher mode setting change unit 76 that controls the change. The change in the setting of the mode of the finisher 14 indicates a staple position movement operation or the like.

  By the way, the main controller 50 is also connected to the operation panel 48 described above, whereby the image forming apparatus 10 inputs various information such as print processing settings, displays the input information, various messages, and the like. Is possible.

  Next, the operation of this embodiment will be described with reference to the flowchart of FIG.

  First, in step 100, an image forming job in the image forming apparatus 10 is started.

  In the next step 102, it is determined whether or not the finisher 14 is performing an initialization operation. If the initialization operation has been performed, the determination is affirmative and the process proceeds to step 112. If the determination is negative in step 102, the process proceeds to step 104.

  In step 104, it is determined whether or not the finisher 14 is performing a set discharging operation. If the set discharge operation has been performed, the determination is affirmed and the process proceeds to step 108, and if the determination is negative in step 104, the process proceeds to step 106.

  In step 106, it is determined whether or not the finisher 14 is changing the mode setting. When the mode setting is changed, the determination is affirmed and the process proceeds to step 110, and when the determination is negative in step 106, the process proceeds to step 108.

  In step 108, it is determined whether or not the number of sheets measured by the print counter 70 is within a predetermined range equal to or less than the reference processing number of sheets for executing the marking setup. Here, the predetermined range equal to or less than the reference processing number is, for example, a range within 100 sheets up to the reference processing number (1,000 sheets), that is, a range from 900 to 1,000 sheets. If it is within the predetermined range, the determination is affirmed and the routine proceeds to step 112.

  Here, the lower limit number of sheets within a predetermined range that is equal to or less than the reference processing number with respect to the reference processing number is shown in Table 1 below.

  On the other hand, at step 110, it is determined whether or not the number of sheets measured by the print counter 70 is the reference number of sheets for executing the marking setup. If it is the reference number of processed sheets, the determination is affirmed and the routine proceeds to step 112. If the result is NO in step 110, the process proceeds to step 114.

  In step 112, a marking setup is performed. When the marking setup is executed, the number of sheets counted by the print counter 70 is reset. For example, when marking setup is executed after 995 images are formed, a mechanism may be used in which counting up starts from −5 sheets (that is, the reference processing number is 1005 in the next measurement).

  Next, in step 114, it is determined whether the operation of the finisher 14 and the marking setup have been completed. If completed, the determination is affirmative and the routine proceeds to step 116. If the result in step 114 is negative, the process proceeds to step 118.

  In step 116, an image is formed on the paper P and sent to the finisher 14. Next, in step 118, it is determined whether or not the image forming job is completed. If completed, the process of the flowchart ends. If the result in step 118 is negative, the process proceeds to step 104.

  Next, the relationship between the execution of the marking setup of the IOT 12 according to the present embodiment and the operation of the finisher 14 will be described with reference to FIG.

  For example, it is assumed that the image forming apparatus 10 is set so that marking setup is performed every 1,000 sheets. On the other hand, the operation of the finisher 14 is based on the setting for each print job. While the finisher 14 is operating, the IOT 12 cannot perform image formation.

  FIG. 4A shows a timing chart in the case where there is no mechanism for synchronizing the execution of the marking setup and the operation of the finisher 14 as in this embodiment.

  The first job indicated by time 4A1 is a job for forming 1,000 images and is the same as the reference processing number. Therefore, after the job is completed, execution of the marking setup indicated by time 4A2 and the finisher 14 are performed. The set discharging operation is performed.

  Next, the second job indicated by time 4A3 is performed. The second job is a job for forming 500 images. After the job is finished, the set discharge operation of the finisher 14 indicated by time 4A4 is performed, and the IOT 12 waits for the end of the set discharge operation.

  Next, the third job indicated by time 4A5 is performed. The third job is a job for forming 450 images. After the job is finished, the set discharge operation of the finisher 14 indicated by time 4A6 is performed, and the IOT 12 waits for the end of the set discharge operation.

  Further, a fourth job indicated by time 4A7 is performed. The fourth job is a job for forming 100 images. However, since 950 images have already been formed from the previous execution of the marking setup before the start of the job, as shown in time 4A7, the marking shown in time 4A8 is performed after 50 images have been formed. Setup is executed. Then, image formation for the remaining 50 sheets is performed after the execution of the marking setup is completed, as indicated by time 4A9.

  On the other hand, the timing in this embodiment of the mechanism which synchronizes execution of marking setup and operation | movement of the finisher 14 is shown in FIG.4 (B). Here, it is assumed that the predetermined range with respect to the reference processing number (1,000 sheets) is 100 sheets.

  After the job for time 4A5 in FIG. 4A ends, the print counter 70 measures 950 sheets, which is a predetermined number of sheets at the end of the job for time 4A5. Therefore, in the present embodiment, the marking setup indicated by the time 4B1 is executed at the timing of the end of the job with respect to the time 4A5. Then, the fourth job indicated by time 4B2 is performed. In the present embodiment, 100 images are formed without being divided. And in this embodiment, downtime can be suppressed only for the time shown by arrow 4B3.

  In FIG. 4, for the sake of convenience, the time spent for executing the marking setup and the time spent for the set discharging operation of the finisher 14 are the same, but even if they are different, the same effect as the present embodiment is obtained. be able to.

  Further, when the finisher 14 changes the mode setting, the same effect as shown in FIG. 4 can be obtained. That is, when the setting of the finisher 14 is changed, even if the number of sheets measured by the print counter 70 is less than the reference processing number, the marking setup is performed if the number is within a predetermined range. . And the effect that downtime is suppressed can be acquired.

  As described above, when the finisher 14 is operated, the control based on the number of the print counter 70 is performed, so that the operation of the finisher 14 and the execution of the marking setup in the IOT 12 can be efficiently synchronized. The decrease in productivity due to execution can be suppressed.

1 is a schematic diagram illustrating a printer according to an embodiment. FIG. 3 is a block diagram illustrating a main configuration of an electric system of the printer according to the embodiment. 6 is a flowchart illustrating a processing flow in the printer according to the embodiment. The relationship between the marking setup of IOT which concerns on this embodiment, and the operation | movement of a finisher is shown.

Explanation of symbols

10 image forming apparatus 12 IOT (image forming unit)
14 Finisher (post-processing section)
20 Transfer belt 22 Developing unit 24 Photosensitive drum 26 Drum cartridge 28 Transfer roller 30 Bias transfer roller 32 Fixing unit 34 Fixing roller 36 Fixing cartridge 42 Booklet creation unit 44 Staple unit 46 Folding unit 48 Operation panel 50 Main controller (instruction means)
52 IOT control unit (image quality adjusting means)
54 drive system control unit 56 charging control unit 58 exposure control unit 60 development control unit 62 transfer control unit 64 fixing control unit 66 color registration detection sensor (image quality adjusting means)
68 Density detection sensor (image quality adjustment means)
70 Print counter (measuring means)
72 Finisher processing control unit 73 Monitoring unit 74 Set discharge controller unit 76 Finisher mode setting change unit

Claims (4)

In an image forming apparatus including an image forming unit that forms an image on a recording sheet and a post-processing unit that performs post-processing on the recording sheet on which the image has been formed.
An image quality adjusting unit that performs image quality adjustment in order to stabilize the image quality of the image, which is executed for each reference processing number set in advance in the image forming unit;
An instruction means for instructing the image quality adjustment means to execute the image quality adjustment regardless of the arrival of the reference processing number so that the time when the post-processing unit operates and the time when the image quality adjustment is performed;
An image forming apparatus comprising:   2. The image forming apparatus according to claim 1, wherein the instruction by the instruction means is valid when the number of processed sheets is a predetermined number smaller than the preset reference number of processed sheets.   The difference between the number of processed images when the image quality adjustment is executed by the instruction unit and the preset reference number of processed images is carried forward to the reference number of processed images for the next image quality adjustment. 2. The image forming apparatus according to 2.   The operation of the post-processing unit includes actual post-processing performed by the post-processing unit and setting change operation of the post-processing performed by the post-processing unit. The image forming apparatus according to claim 1.

Images