JP2017067866A - Image forming apparatus and image forming method with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in which: in calculating the consumption of a recording agent on the basis of a dot count value based on image data, the consumption of the recording agent cannot be accurately measured when the length of an image exceeds the length of a recording sheet and image formation is interrupted due to the occurrence of paper jam.SOLUTION: An image forming apparatus comprising image forming means that forms an image on a recording medium with a recording agent on the basis of image data input thereto, performs the following processing. That is, the image forming apparatus calculates the amount of the recording agent to be used for the recording medium on the basis of the image data input to the image forming apparatus, subsequently determines the consumption of the recording agent on the basis of a calculated value, and then corrects a result of the determination from a difference between the calculated value and the amount of the recording agent actually used for the recording medium from the size of the recording medium on which the image is formed by the image forming means.SELECTED DRAWING: Figure 6

Description

  The present invention relates to an image forming apparatus and an image forming method thereof, and more particularly, to an image forming apparatus and an image forming method for forming an image on a recording medium using an electrophotographic system.

  2. Description of the Related Art Conventionally, there is an image forming apparatus that receives image data from a host computer (host apparatus) or an image reading apparatus (scanner) and forms an image on a recording medium. In this case, at least one of the host device and the scanner and the image forming apparatus constitute an image forming system. In addition, the image forming apparatus includes: a controller that develops a bitmap of input image data in a memory and outputs the bitmap-expanded image data; and a printer engine that records an image on a recording medium based on the bitmap image data Including.

  Some printer engines use an electrophotographic method to form an image on a recording medium using toner, and others use an ink jet method to form an image by ejecting ink onto a recording medium.

  In such an image forming system, there is a problem that it is desired to efficiently calculate the consumption amount of consumables such as toner and ink. In order to solve this problem, for example, Patent Document 1 proposes the following technique. That is, the host device transmits image data for each page of the recording medium to the image forming apparatus, and the dot count data corresponding to the page until the image forming apparatus finishes forming the image corresponding to the image data. Is transferred from the host device to the image forming apparatus. As a result, the page on which the image is formed and the corresponding dot count data are associated with each other on a one-to-one basis, so that the consumption amount of the consumable material actually consumed for image formation can be accurately obtained.

JP 2006-185091 A

  However, in the above conventional example, when the paper size used for image formation is smaller than the size of the image data used for dot count, the image processing portion masks the image data that protrudes from the paper, and Only the amount of image data to be recorded is used. For this reason, there is a discrepancy between the image data used for dot counting and the image data actually used for the image formed on the paper, and the consumption of the consumable material is not correctly measured.

  In addition, even when image formation stops during recording due to paper jams, etc., there is a discrepancy between the image data used for dot count and the image data actually used for the image formed on the paper. And the consumption of consumables is not measured correctly.

  The present invention has been made in view of the above-described conventional example, and it is possible to accurately determine the consumption amount of a recording agent as a consumable material even if a mismatch between generated image data and image data actually used for image formation occurs. An object is to provide a possible image forming apparatus and an image forming method thereof.

  In order to achieve the above object, the image forming apparatus of the present invention has the following configuration.

  That is, an image forming apparatus that forms an image on a recording medium with a recording agent, and an arithmetic unit that calculates an amount of the recording agent to be used for the recording medium based on image data input to the image forming apparatus; Determination means for determining the consumption amount of the recording agent based on a value calculated by the calculation means, image forming means for forming an image on the recording medium with the recording agent based on the image data, and the image formation Correction means for correcting the consumption of the recording material determined by the determination means from the difference between the amount of the recording material actually used for the recording medium by the means and the calculated value of the calculation means. And

  According to the present invention, there is an effect that the consumption amount of the recording agent used for image formation on the recording medium can be obtained with high accuracy.

1 is a side sectional view showing a schematic configuration of an image forming apparatus that forms an image according to an electrophotographic system that is a representative embodiment of the present invention. FIG. 2 is a block diagram illustrating a control configuration of the image forming apparatus illustrated in FIG. 1. It is the top view and side view which show the structure of the multipurpose tray (MPT) shown in FIG. It is a flowchart which shows the paper insertion monitoring process of MPT performed by MPU. It is a figure which shows the example of the display screen of an operation part. It is explanatory drawing which shows roughly the relationship between image data and a recording paper. 4 is a flowchart illustrating a dot count control process of the image forming apparatus. FIG. 3 is a diagram illustrating an outline of print data management in a printer controller. It is a flowchart which shows sheet feeding conveyance control of an engine controller. , 4 is a flowchart illustrating print control of a printer controller.

  Hereinafter, preferred embodiments of the present invention will be described more specifically and in detail with reference to the accompanying drawings.

  In this specification, “recording” (sometimes referred to as “printing”) is not limited to the case of forming significant information such as characters and graphics, but may be significant. Furthermore, it also represents a case where an image, a pattern, a pattern, or the like is widely formed on a recording medium or a medium is processed regardless of whether or not it is manifested so that a human can perceive it visually.

  The “recording medium” includes not only paper used in general recording apparatuses but also widely includes cloth, plastic film, metal plate, glass, ceramics, wood, leather, and the like.

  FIG. 1 is a side sectional view showing a configuration of an image forming apparatus 1 for forming an image according to an electrophotographic system which is a typical embodiment of the present invention.

As shown in FIG. 1, the image forming apparatus 1 has cassettes 61 and 62 for storing a recording medium such as recording paper S in the supply unit 2, and the cassettes 61 and 62 each have pickup rollers for picking up recording paper from each. 71 and 72 are arranged. Further, the supply unit 2 is provided with feeding rollers 91 and 92 for feeding the picked-up recording paper. In addition,
The cassettes 61 and 62 can store recording media of the same size or different sizes.

  On the other hand, the image forming apparatus 1 has a multi-purpose tray (hereinafter referred to as MPT) 10 that can manually supply non-standard paper, and is provided with a feed roller 12 for feeding recording paper from the MPT 10. Then, the conveyance path 13 from the cassettes 61 and 62 and the conveyance path 11 from the MPT 10 merge at a merging point 16, and the recording sheet conveyed further downstream reaches the registration roller 15.

  The registration roller 15 is positioned between the cassettes 61 and 62 and the image forming unit 3, and between the MPT 10 and the image forming unit 3, and synchronizes the recording paper S conveyed from the supply unit 2 or the MPT 10 with image formation. The roller is sent to the image forming unit 3. The recording paper S is positioned at the time of image formation by abutting the leading edge of the recording paper S with the non-driven registration roller 15. The recording sheet S is sent to the image forming unit 3 by the registration roller 15 being driven to rotate in synchronization with a vertical synchronization signal (VSYNC) of image data output from an engine controller 100 (described later).

  A pre-registration sensor 30 is disposed on the upstream side of the registration roller 15 in the conveyance direction of the recording paper and on the conveyance path between the cassettes 61 and 62. The pre-registration sensor 30 is an interactive type sensor that detects the presence of a recording sheet at that position by blocking the light emitted from the light-emitting portion when the recording sheet contacts. Similarly, a pre-registration sensor 31 is also disposed on the conveyance path 11 between the MPT 10 and the junction 16 to detect the presence or absence of recording paper conveyed from the MPT 10 toward the registration roller 15.

  An image forming unit 3 that forms an image with a laser beam from the semiconductor laser 21 is disposed downstream of the registration roller 15 in the recording paper conveyance direction. The image forming unit 3 includes a photosensitive drum 20 and a transfer roller 22. The photosensitive drum 20 is scanned by laser light from the semiconductor laser 21 to form an electrostatic latent image on the surface thereof, and the electrostatic latent image is developed with toner. The toner image formed on the photosensitive drum 20 is transferred to the recording paper S conveyed by the registration roller 15 when a bias voltage is applied to the transfer roller 22.

  Further, a fixing unit 5 is disposed downstream of the image forming unit 3 in the recording paper conveyance direction. The fixing unit 5 fixes the toner image on the recording sheet S by heating and pressing the recording sheet S on which the toner image has been transferred by the image forming unit 3. The recording paper S discharged from the fixing unit 5 is sorted by the flapper 27 and discharged to the paper discharge trays 23 and 25. In the case of double-sided printing, a part of the recording paper S is discharged to the paper discharge tray 23 and then the discharge roller. 32 is pulled back to the transport path 26. The recording sheet pulled back to the transport path 26 is returned to the junction 16 of the transport path by the transport rollers 33 and 34. By doing so, double-sided recording becomes possible.

  FIG. 2 is a block diagram showing a control configuration of the image forming apparatus shown in FIG. As shown in FIG. 2, the operation of the image forming apparatus is controlled by an engine controller 100 and a printer controller 200.

  The printer controller 200 is connected to the host computer 40 and the document reading device 50 which are image data generation sources via an external interface (IF) 204, and is connected to the operation unit 300 via the operation unit IF 206. Further, it is connected to the engine controller 100 via the engine IF 205. The external interface (IF) 204 may be a general-purpose interface such as a USB interface or a dedicated interface.

  The printer controller 200 includes an MPU 201 that controls the entire apparatus, an image processing IC 202 that performs image processing on image data input via the external interface 204, and an image memory 203 necessary for the image processing. The MPU 201 includes a ROM (not shown), a RAM (not shown), and a timer (not shown). The MPU 201 controls the operation of the image forming apparatus by reading and executing a control program stored in the ROM while using the RAM as a work area.

  The image processing IC 202 performs image processing such as density correction and binarization on the input image data, and then compresses and encodes the image-processed data, and pages into the compressed image data area 203a of the image memory 203. Save in units. When executing image formation based on the image data, the image processing IC 202 reads and decodes the compressed image data from the compressed image data area 203 a and develops it in the bitmap data area 203 b of the image memory 203. At this time, the image processing IC 202 counts pixels (dots) constituting the image while developing the compressed image data as a bitmap.

  The MPU 201 monitors the progress of the bitmap development, and estimates the timing when the engine controller 100 accesses the bitmap data area 203b and reads the image data so that the address does not overtake the bitmap development address. Then, it notifies the engine controller 100 connected via the engine IF 205 of the image formation start timing.

  On the other hand, the engine controller 100 connects the above-described supply unit 2, image forming unit 3, and fixing unit 5 through an input / output interface (IF) 103, and connects the printer controller 200 through a controller interface (IF) 102. The engine controller 100 includes an MPU 101 that includes a ROM (not shown) and a RAM (not shown). The MPU 101 reads out and executes a control program stored in the ROM while using the RAM as a work area, and forms an image. The operations of the unit 3 and the fixing unit 5 are controlled.

  FIG. 3 is a top view and a side view showing the structure of the MPT 10 shown in FIG. In FIG. 3, the upper half is a top view of the MPT 10 and the lower half is a side view of the MPT 10.

  The user slides the side regulating plate 17 on the MPT 10, widens the position width of the side regulating plate 17 than the width of the recording paper S, and then inserts the sheet S into the MPT 10. After setting the recording paper S on the MPT 10, the user slides the side regulating plate 17 until it hits both ends of the sheet S. The MPT10 has the same width as A5 (width 210 mm × length 148.5 mm) and A4R (width 210 mm × 297 mm), A4 (width 297 mm × length 210 mm) and A3R (width 297 mm × length 420 mm). The widths of the recording sheets S of different sizes can be set in a bundle.

  The side regulating plate 17 aligns the end portions of the recording paper S bundle, and suppresses skew when being conveyed into the image forming apparatus. Further, the slide mechanism of the side restricting plate 17 is connected to a slide resistance (not shown), and the voltage changes proportionally in the range of 0 to 3.3 V according to the slide position of the side restricting plate 17. An output voltage (0 to 3.3 V) from the slide resistor is input to the engine controller 100, and is converted into a digital value of 0 to 255 by an A / D converter included in the MPU 101.

  The MPU 101 can know the width of the side regulating plate 17, that is, the width of the recording paper S, from this digital value (X = 0 to 255). When the width (W) of the recording paper that can be set in the MPT 10 is in the range of 139 to 297 mm, X = 5 when W = 139 mm and X = 252 when W = 297 mm can be calculated as follows. Since the slide position of the side regulating plate 17 and the output voltage of the slide resistance are in a proportional relationship, the slope K = (297-139) / (252-5) = 0.64, and the digital value indicating the slope K and the current width. From X, the current width of the recording paper is calculated as W = (X−5) × K + 139. The MPU 101 uses this equation to calculate and determine the width of the recording paper, for example, W = 200 mm when X = 100 and W = 168 mm when X = 50.

  FIG. 4 is a flowchart showing the paper insertion monitoring process of the MPT 10 executed by the MPU 101.

  First, in step S130, the change in the output of the pre-registration sensor 31 of the MPT 10 is examined. If the output indicates that there is recording paper, the process proceeds to step S132 to check whether the output voltage from the slide resistance (digital value converted by the A / D converter) is stable. . Here, at the timing when the variation in the output voltage is eliminated (that is, the timing when the sliding operation of the side regulating plate 17 is stopped), the process proceeds to step S132, and the output state of the pre-registration sensor 31 of the MPT 10 is confirmed again.

  If the output of the pre-registration sensor 31 indicates that there is no recording paper (OFF state), the process returns to step S130 and monitoring of the output of the pre-registration sensor 31 is continued. On the other hand, when the output of the pre-registration sensor 31 indicates that the recording paper is present (ON state), the process proceeds to step S133, and the output voltage from the slide resistance is acquired. In step S134, the width of the recording paper is calculated using the above-described calculation formula. In step S135, the printer controller 200 is notified of the calculated width of the recording paper.

  Thereafter, the process returns to step S132, and the confirmation of whether or not the output voltage of the slide resistance is stable is continued.

  FIG. 5 is a diagram illustrating an example of a display screen of the operation unit. FIG. 5 shows an example in which a paper size selection screen used when inserting a recording paper using the MPT 10 is displayed.

  The operation unit 300 is controlled by the printer controller 200 as described above. The operation unit 300 uses a touch panel display device and can be operated by a user touching a menu or button displayed on the screen.

  The operation unit 300 of the image forming apparatus of this embodiment displays a standby screen 301 shown on the left side of FIG. 5 during standby after the power is turned on. When the recording paper S is inserted into the MPT 10 in this state, the width of the recording paper detected from the engine controller 100 is notified to the printer controller 200 in mm units as described with reference to FIG. The The printer controller 200 displays a paper size selection screen 302 shown on the right side of FIG. 5 based on the notified recording paper width. When the notified width of the recording paper matches the standard paper such as A4 or A3R width of 297 mm, all the candidates for the matching standard paper size are displayed.

  In the example of the paper size selection screen 302 in FIG. 5, “A4” and “A3R” are displayed. When the size of the recording paper S is not handled as a standard paper, when the user selects the “free” button displayed on the screen, the recording paper S is handled as a free-size paper of unknown length. Since the recording paper S set in the MPT 10 is defaulted to a free size paper, the initial screen after switching to the paper size selection screen 302 is displayed with the “free” button selected.

  When the “Close” or “OK” button is selected on the paper size selection screen, the size selected immediately before is determined, and the display is switched to the standby screen 301. The width and length information of the recording sheet S whose size has been determined is also notified from the printer controller 200 to the engine controller 100, and the image forming operation of the image forming apparatus 1 is controlled based on the determined width and length information. The In the case of free-size paper, the width direction is notified by the width of the recording paper detected by the output voltage of the slide resistance, and the length direction is notified by dummy data = −1 (2-byte hexadecimal number FFFFh) indicating unknown.

  FIG. 6 is an explanatory diagram schematically showing the relationship between image data and recording paper.

  In FIG. 6, during the “print job in progress” period, the printer controller 200 sequentially develops the compressed image data 1 to n in the image memory 203 into the image memory 203 as image data 1 to n as a bitmap. Further, FIG. 6 shows a state in which image data 1 to n are sequentially transmitted to the engine controller 100 at a predetermined timing, and images are sequentially formed on the sheets 1 to n.

  The printer controller 200 ends the bitmap development of the compressed image data for each page of the recording paper, and when the dot count of the image data after the bitmap development is finished, the printer controller 200 sets the dot count value to the engine controller 100 as indicated by arrows D1 to Dn. Notice. The engine controller 100 calculates the toner consumption amount used in image formation based on the notified dot count value. In addition, the engine controller 100 notifies the printer controller 200 of the sheet length for each page of recording paper measured using the pre-registration sensor 30 on the conveyance path at the timings indicated by arrows L1 to Ln.

  Here, when the recording paper used for image formation is the free size paper described with reference to FIG. 5, there may be a discrepancy between the size of the image data and the size of the recording paper.

  Here, regarding the image formed based on the image data, if the length in the conveyance direction of the recording paper is the image data length (IL) and the length in the conveyance direction of the recording paper is the recording paper length (PL), IL When ≦ PL, the image fits on the recording paper. On the other hand, when IL> PL, the image protrudes from the sheet. This protrusion is shown as a hatched portion on the right side of the sheet in FIG. The engine controller 100 transmits an image transmitted from the printer controller 200 starting from the detection timing of the trailing edge of the recording sheet by the pre-registration sensor 30 so that the image forming apparatus 1 is not contaminated with toner by forming an image that protrudes from the recording sheet. Mask the data. As a result, the formation of an image that protrudes from the recording paper is suppressed.

  The printer controller 200 suspends execution of the print job when IL> PL regarding the recording paper length (PL) notified from the engine controller 100. After that, based on the recording paper length notified from the engine controller 100, the bitmap development and dot count of the image data of all the corresponding pages are performed to calculate the dot count correction value. Then, as indicated by arrows C1 to Cn-1, the engine controller 100 is notified of the dot count correction value.

  FIG. 7 is a flowchart showing dot count control processing of the image forming apparatus. Here, a process is shown in which the engine controller 100 calculates the toner consumption based on the dot count value received from the printer controller 200.

  First, in step S140, the engine controller 100 checks whether or not a dot count value (DCNT) is notified from the printer controller 200.

  If the dot count value has been notified, the process proceeds to step S141, and the notified dot count value (DCNT) is acquired. In step S142, the received dot count value (DCNT) is added to the dot count cumulative value (ACNT) to update the dot count cumulative value. Thereafter, in step S143, the process converts the updated dot count cumulative value (ACNT) into a toner consumption amount and stores it. Thereafter, the process returns to step S140, and the notification of the dot count value is monitored.

  On the other hand, if there is no notification of the dot count value, the process proceeds to step S144 to check whether there is a notification of the dot count correction value.

  Here, if there is no notification of the dot count correction value (CORR), the process returns to step S140, and the notification of the dot count value is monitored. On the other hand, when the dot count correction value (CORR) is notified, the process proceeds to step S145, and the notified dot count correction value (CORR) is acquired. Further, in step S146, the dot count accumulated value is updated by subtracting the received dot count correction value (CORR) from the dot count accumulated value (ACNT). Thereafter, the process proceeds to step S143, and the above-described process is executed.

  FIG. 8 is a diagram for explaining the outline of print data management in the printer controller. This figure shows a state in which the MPU 201 of the printer controller 200 manages print data.

  At the start of a print job, the MPU 201 generates print job management data 401 and dot count correction management data 501.

  According to FIG. 8, after initialization of the apparatus, page data 402 for the necessary pages is sequentially generated from the first page, and the print job management data 401 sequentially points to the data addresses of the page data 402, so that the print job data queue 400 is configured.

The print job management data 401 is composed of the following data. That is,
First page data (top_p) indicating the data address of the first page data 402,
Job identification ID (job_ID) for identifying and managing print jobs with unique ID numbers,
A printing page (print_p) indicating the data address of the page data 402 being printed;
Number of copies that hold the number of copies of the print job (cycle_NUM),
A copy counter (cycle_CNT) indicating the number of copies printed,
Other management data.

The page data 402 is composed of the following data. That is,
Next page data (next_p) indicating the data address of the next page data 402,
A page identification ID (page_ID) for identifying the print page with a unique ID number;
A compressed data address (img_adr) that points to the compressed image data address of the print page,
Print page image width (img_X),
Print page image length (img_Y),
Dot count value (dot_CNT) of image data on the print page,
Other management data.

  Here, the image width of the print page is a size in a direction orthogonal to the recording paper conveyance direction, and the image length is a size in the recording paper conveyance direction. Note that the width of the recording sheet can be specified from the cassette setting if it is a standard sheet such as A4 or B5, but if it is manually inserted from the MPT 10, the slide of the side regulating plate 17 It can be identified from the position.

  The MPU 201 sequentially follows the page data as indicated by the first page data (top_p), the next page data (next_p), and the next page data (next_p) as indicated by the arrow in FIG. Perform the printing process.

  The next page data (next_p) of the page data 402 of the last page is 0 (null) data indicating the last page. When the MPU 201 reaches the last page, the copy counter (cycle_CNT) of the print job management data 401 is counted up. . The MPU 201 repeats printing from the top page data 402 until the number of copies counter (cycle_CNT) reaches the same value as the number of copies (cycle_NUM). When a print job is stopped due to a jam, printing is resumed from the page data 402 indicated by the printing page (print_p) when the jam processing by the user is completed.

  When the dot count value (dot_CNT) is “0” at the end of the dot count of the image data of each page data 402, the MPU 201 writes the dot count value to the dot count value (dot_CNT).

The MPU 201 generates dot count correction data 502 for each page in which the recording paper length (PL) notified from the engine controller 100 is smaller than the image length (IL) and IL> PL. The dot count correction data 502 is composed of the following data. That is,
Next page data (next_p) indicating the data address of the next dot count correction data,
Refers to the data address of the correction page data (page_p),
Corrected image length (img_Y2) using the received recording paper length as the image length for dot count correction
It is.

  The data address of the dot count correction data 502 generated first is written in the correction data (comp_top_p) of the dot count correction management data 501. The data address of the next generated dot count correction data 502 is written to the next page data (next_p) of the dot count correction data 502 generated last time. Thereafter, each time the dot count correction data 502 is generated, the generated data address is written in the next page data (next_p) of the previous dot count correction data 502, whereby the dot count correction data queue 500 is formed. In the next page data (next_p) of the last dot count correction data 502, 0 (null) data indicating the last data is written.

  The MPU 201 executes the following process after the print job is stopped (including the job stoppage due to the occurrence of a jam). That is, when the data address of the dot count correction data 502 is written in the correction data (comp_top_p) of the dot count correction management data 501, the dot count correction processing is sequentially performed from the head to the last dot count correction data.

  The MPU 201 executes bitmap expansion of the compressed image data and dot count based on the data of the page data 402 indicated by the correction page data (page_p) of the dot count correction data 502. The bitmap development and dot count at that time are up to the corrected image length (img_Y2) of the dot count correction data 502. The MPU 201 notifies the engine controller 100 of the difference between the dot count value (dot_CNT) of the page data 402 and the dot count value obtained up to the corrected image length (img_Y2) as a dot count correction value (CORR).

  FIG. 9 is a flowchart showing the paper feed and conveyance control of the engine controller.

  First, in step S101, when image formation is requested, a sheet of recording paper is picked up from a designated cassette or MPT recording paper bundle, and paper feeding is started. In step S102, a jam timer is activated to confirm that the pre-registration sensor 30 on the transport path detects the leading edge of the recording paper within a predetermined time.

  Next, in step S103, it is confirmed whether an emergency stop request due to a jam, an error, or the like has occurred under control other than feeding and transport processing. If there is no emergency stop request, the process proceeds to step S104, and a jam timer timeout (elapse of a predetermined time) is confirmed. If the jam timer has not timed out, the process advances to step S105 to check whether the leading edge of the recording paper has been detected from the output (ON / OFF) of the pre-registration sensor 30 on the conveyance path. On the other hand, if there is an emergency stop request in step S103 or if the jam timer times out in step S104, the process proceeds to step S119. In step S119, the recording paper feeding operation and the jam timer are stopped, and then the process proceeds to step S123 to notify the printer controller 200 of a jam.

  In step S105, if the output of the pre-registration sensor 30 is OFF, the process returns to step S103 and continues the emergency stop request monitoring process. On the other hand, when the output of the pre-registration sensor 30 is ON, the process proceeds to step S106, the jam timer is stopped, and further, in step S107, the skew correction is executed to convey the recording paper straight to the image forming unit 3. . After the skew correction is completed, in step S108, a registration clutch (not shown) is turned on to convey the recording paper to the image forming unit 3. At the same time, in step S109, the jam timer is started again to confirm that the trailing edge of the recording paper passes the pre-registration sensor 30 at a predetermined timing. This jam timer is also used as a recording paper length measurement timer for measuring the length (PL) of the recording paper in the transport direction.

  In step S110, the image forming unit 3 is instructed to start image formation, and further discharge control is instructed, and image formation on the recording paper and discharge control of the recording paper to the outside of the apparatus are performed. Next, in step S111, it is confirmed whether there is an emergency stop request, and in step S112, a timeout of the jam timer is confirmed. If the emergency stop request is not confirmed and the jam timer has not timed out, the process proceeds to step S113 to check whether the output of the pre-registration sensor 30 is OFF. If the output from the pre-registration sensor 30 is ON (recording paper is present), the process returns to step S111. If the output from the pre-registration sensor 30 is OFF (no recording paper), the process proceeds to step S114. move on.

  On the other hand, if it is confirmed in step S111 that an emergency stop request has been made, or if it is confirmed in step S112 that the jam timer has timed out, the process proceeds to step S120. In step S120, the jam timer is stopped, and in step S121, the recording paper length (PL) is calculated based on the count value (TIME) of the jam timer up to that point. This is calculated from TIME × recording conveyance speed (v). In step S122, the printer controller 200 is notified of the calculated recording paper length. If the recording paper length is known, the photosensitive drum 20 rotates according to the same length, and an electrostatic latent image is formed on the surface, and the electrostatic latent image is developed with toner. Based on the above, the actual toner consumption amount to the recording paper in which the jam has occurred is also calculated. Thereafter, in step S123, a jam notification is performed as described above.

  In step S114, the jam timer is stopped, and in step S115, the recording paper length is calculated. This is calculated from TIME × recording conveyance speed (v) + L (distance from the pre-registration sensor to the registration roller). In step S116, the printer controller 200 is notified of the calculated recording paper length. If the recording paper length is known, the photosensitive drum 20 rotates according to the same length to form an electrostatic latent image on the surface thereof, and the electrostatic latent image is developed with toner. Based on the length, the actual toner consumption is also calculated.

  In step S117, image data masking is started so that the image does not protrude from the recording paper, the image forming unit 3 is instructed to end image formation, and image formation processing for each page is stopped. Finally, in step S118, the registration clutch is turned off, and the feeding / conveying control is terminated.

  10 to 11 are flowcharts showing print control of the printer controller.

  At the start of printing, it is checked in step S201 whether print job management data 401 already exists. If there is no print job management data 401, the process proceeds to step S202, where the dot count correction management data 501 is cleared. In step S203, the print job management data 401 and page data 402 are generated and the print job data queue 400 is stored. Generate. In step S204, the first page data in the print job data queue 400 is set as a printing page.

  On the other hand, if the print job management data 401 already exists, the process proceeds to step S205, and printing is resumed from the printing page of the print job management data. After checking the pages being printed, check whether all the pages are finished. Here, if the printing of all the numbers has not been completed, the process proceeds to step S206, and bitmap expansion of the compressed image data of the printing page is started. In step S207, it is confirmed whether the dot count value (dot_CNT) of the print page data is “0”. If the dot count value (dot_CNT) of the print page data is not “0”, the process proceeds to step S209. On the other hand, when the dot count value (dot_CNT) is 0 (unmeasured), the process proceeds to step S208 to start the dot count. In step S209, the process waits until the timing of the bitmap development advances and the image can be output.

  In step S209, the process proceeds to step S210 at the timing when the image output is enabled, and the engine controller 100 is instructed to start feeding. In step S211, the jam notification from the engine controller 100 is monitored. Further, in step S212, a vertical synchronization signal (VSYNC) for synchronizing the leading edge of the recording paper being conveyed by the image forming apparatus and the leading edge of the image data developed in the bitmap is monitored. If a jam notification is received, the process proceeds to step S241 where output of image data is stopped, dot count is stopped in step S242, and bitmap development is stopped in step S243. Thereafter, the process proceeds to step S230, and it is confirmed whether or not dot count correction data 502 exists.

  On the other hand, when the vertical synchronization signal (VSYNC) which is “ON” is received, the process proceeds to step S213 to start outputting image data. In step S214, the notification of the recording paper length from the engine controller 100 is monitored. If there is no notification of the recording paper length, the process proceeds to step S219 to monitor the end of bitmap development. On the other hand, if there is a notification of the recording paper length, the process proceeds to step S215 to acquire the recording paper length (PL), and in step S216, the recording paper length (PL) is compared with the image length (IL). If the image length is larger than the recording paper length and PL <IL, the process proceeds to step S217 to generate dot count correction data 502 and store the received recording paper length (PL) as the corrected image length. . In step S218, the dot count correction data 502 is connected to the dot count correction data queue 500. Thereafter, the process proceeds to step S219. On the other hand, if PL ≧ IM, the process proceeds directly to step S219.

  If it is determined in step S219 that the bitmap development has not been completed, the process returns to step S214. If it is determined that the bitmap development has been completed, the process proceeds to step S220. Then, it is confirmed whether or not the dot count value (dot_CNT) of the print page is “0 (not measured)”. If the dot count value (dot_CNT) is “0”, the process advances to step S221 to stop the dot count and save the measured dot count value in the page data. In step S222, the engine controller 100 is notified of the dot count value (dot_CNT). Thereafter, the process proceeds to step S223. On the other hand, if the dot count value (dot_CNT) is not “0”, the process proceeds directly to step S223.

  In step S223, reception of a jam notification from the engine controller 100 is monitored, and in step S224, completion of image data output is monitored. If a jam notification is received, the process proceeds to step S241 to stop outputting image data, stop the dot count in step S242 as described above, and stop bitmap development in step S243. Thereafter, the process proceeds to step S230, and it is confirmed whether or not dot count correction data exists. If the output of the image data comes to the end timing, the process proceeds to step S225. In step S226, the output of the image data is stopped and it is confirmed whether there is next page data. On the other hand, if the output of the image data has not reached the end timing, the process returns to step S223 to continue the above monitoring.

  If it is confirmed in step S226 that there is next page data, the process proceeds to step S227, the page data of the next page is set as a printing page, and the process returns to step S206. On the other hand, if there is no next page data, the process proceeds to step S228, the number counter is counted up, and the process returns to step S204.

  If it is determined in step S205 that all the printing has been completed, the process proceeds to step S229 to clear the printing page. In step S230, it is checked whether dot count correction data 502 exists in the dot count correction data queue 500. If the dot count correction data 502 is present, the process proceeds to step S231, where the compressed image data of the page is started to be developed with a corrected image length, and the dot count is also started in step S232. In step S233, the end of bitmap development is monitored. When the bitmap development ends, the process proceeds to step S234, and the dot count is stopped.

  In step S235, a dot count correction value is calculated. In step S236, the calculated dot count correction value is notified to the engine controller 100. In step S237, the head of the dot count correction data queue 500 is switched to the next page data of the dot count correction data. In step S238, the dot count correction data is deleted. Thereafter, the process returns to step S230, where it is confirmed whether or not the dot count correction data 502 exists in the dot count correction data queue 500, and the process is repeated until the dot count correction data queue 500 becomes empty.

  If it is determined in step S230 that the dot count correction data queue is empty, the process proceeds to step S239 to check whether the print job management data 401 includes a printing page. If there is no page being printed, the process advances to step S240 to delete the data managed in the print job data queue and finish printing. On the other hand, if there is a page being printed, the process leaves the print job data queue as it is and ends the process.

  Therefore, according to the embodiment described above, when the length of the recording paper used for image formation is less than the length of the image to be formed, the dot count value of the image corresponding to the amount protruding from the recording paper is used. It is possible to correct the dot count value based on the generated image data. As a result, it is possible to accurately obtain the toner consumption amount actually used for image formation. Further, by correcting the dot count value after stopping the print job, there is also an advantage that the toner consumption amount can be obtained without degrading the image forming performance.

  In the above-described embodiments, a single-function image forming apparatus has been described as an example, but the present invention is not limited thereto. For example, an image forming apparatus that includes an ADF unit that automatically feeds recording paper to the image forming apparatus described above, an image forming apparatus that includes a memory print function, and a multi-functional image forming apparatus that includes a scanner function may be used.

  In the above-described embodiments, the image forming apparatus that forms an image according to the electrophotographic method is used as an example. Therefore, the recording agent for forming an image on a recording medium is toner, but the image is formed according to the ink jet method. In this case, the recording agent becomes ink.

  Furthermore, the present invention supplies a program that realizes one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in the computer of the system or apparatus read and execute the program This process can be realized. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

1 image forming apparatus, 2 supply unit, 3 image forming unit, 5 fixing unit,
10 Multipurpose tray (MPT), 15 Registration roller, 20 Photosensitive drum,
21 semiconductor laser, 22 transfer drum, 30-31 sensor before registration,
33-34 conveying roller, 61-62 cassette, 71-72 pickup roller,
91-92 feeding rollers,

Claims (8)

An image forming apparatus for forming an image on a recording medium with a recording agent,
A computing means for computing the amount of the recording material to be used for the recording medium based on the image data input to the image forming apparatus;
A determination unit that determines a consumption amount of the recording agent based on a calculation value obtained by the calculation unit;
Image forming means for forming an image with the recording agent on a recording medium based on the image data;
And a correction unit that corrects the consumption of the recording agent determined by the determination unit from the difference between the amount of the recording agent actually used on the recording medium by the image forming unit and the calculation value of the calculation unit. An image forming apparatus.   The correction means detects the amount of the recording material actually used in the recording medium, and corrects the consumption amount of the recording material determined by the determination means based on a difference from the calculation value of the calculation means. The image forming apparatus according to claim 1. A comparison means for comparing the size of the image formed based on the image data and the size of the recording medium;
When it is determined by the comparison by the comparison means that the size of the image is larger than the size of the recording medium, the image data further includes mask means for masking image data corresponding to the large amount,
The image forming apparatus according to claim 1, wherein the image forming unit forms an image based on the image data masked by the mask unit. Conveying means for conveying the recording medium;
A detection unit that is provided upstream of the image forming unit with respect to a conveyance direction in which the recording medium is conveyed by the conveyance unit, and that detects a leading edge and a trailing edge of the recording medium;
The image forming means starts image formation based on the detection timing of the leading edge of the recording medium by the detection means, and based on the timing of detection of the trailing edge of the recording medium by the detection means, The image forming apparatus according to claim 3, wherein the formation is terminated. A notification means for notifying the correction means of the length in the conveyance direction of the recording medium based on the detection timing of the leading edge and the trailing edge of the recording medium by the detection means at the end of the image formation;
The correction unit calculates the amount of the recording agent actually used by the image forming unit on the recording medium based on the length in the conveyance direction of the recording medium notified by the notification unit and the image data. The image forming apparatus according to claim 4. A timer that is activated based on the detection timing of the leading edge of the recording medium by the detection means and measures time;
Determining means for determining whether a jam has occurred in the recording medium conveyed by the conveying means based on the time measured by the timer;
The determination means determines that a jam has not occurred when the detection means detects the trailing edge of the recording medium before the time measured by the timer has passed a predetermined time; 6. The image forming apparatus according to claim 5, wherein when the time measured by the timer exceeds the predetermined time, it is determined that a jam has occurred. When it is determined by the determining means that a jam has occurred, the masking of the image data by the masking means, the conveyance of the recording medium by the conveying means, and the stop of the image formation by the image forming means are performed. Control means for controlling
The notifying unit notifies the correction unit of the length in the conveyance direction of the recording medium based on the conveyance speed by the conveyance unit and the predetermined time when the image formation is stopped. The image forming apparatus according to claim 6. An image forming method of an image forming apparatus provided with an image forming means for forming an image with a recording agent on a recording medium based on input image data,
A calculation step of calculating an amount of a recording agent to be used for the recording medium based on image data input to the image forming apparatus;
A determination step of determining the consumption of the recording agent based on the calculated value in the calculation step;
And a correction step of correcting the consumption of the recording agent in the determination step from the difference between the amount of the recording agent actually used on the recording medium by the image forming unit and the calculated value in the calculation step. An image forming method.

Images