JP2005266287A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus with which so-called throughput can be increased by allowing a margin of the timing of an adjustment operation such as stir/supply of toner stored in each developing cartridge, thereby avoiding forcibly initiating the adjustment operation. <P>SOLUTION: The image forming apparatus includes a rotary unit which stores the plurality of developing cartridges for developing electrostatic latent images on the surface of a photoreceptor drum and rotates to switch to the developing cartridge to be used. The image forming apparatus makes adjustment for consecutive image formation by inverting stored toner in each developing cartridge upside down accompanying the rotation of the rotary unit during image formation. In the case where the consumption of the stored toner used is within the limit of consumption even after exceeding a preset margin of consumption, an image forming job is completed without switching the developing cartridge. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus, and more particularly to an apparatus for forming an image while rotating a plurality of developing cartridges.

  2. Description of the Related Art Conventionally, an electrophotographic recording type image forming apparatus that exposes and forms an electrostatic latent image on the surface of a carrier made of a photoreceptor is known. In this image forming apparatus, the electrostatic latent image is developed with toner. The toner image on the surface of the carrier carried in this manner is transferred to a recording medium such as recording paper to form an image. The electrostatic latent image is developed by rotating the developing roller facing the surface of the carrier and transferring the toner on the surface to adhere the toner. The supply roller that rotates in the space rotates by pressure to supply toner.

  An image forming apparatus that employs this electrophotographic recording system includes an apparatus that can store a plurality of developing cartridges including a developing roller and a supply roller facing a carrier together with a container for storing toner in a rotary unit. . In this image forming apparatus, the developing cartridge at the developing position facing the carrier can be switched by rotating the rotary unit about the rotation axis.

  For this reason, such an image forming apparatus is a developing cartridge that contains toner of yellow (Y), magenta (M), cyan (C), and black (K) as a developing cartridge that attaches toner to the surface of the carrier. By configuring the cartridge so that it can be stored (mounted) in the rotary unit, it is possible to sequentially switch the developing cartridges and form a color image in which the respective colors are superimposed. In this configuration, it is needless to say that a monochrome image using a single color toner, for example, a black and white monochrome image (hereinafter also simply referred to as a monochrome image) using black (K) toner can be formed.

In addition, it has been proposed that an image forming apparatus including a rotary unit as described above be configured so that a plurality of developing cartridges that store toner of the same color (mainly black) can be mounted. In this configuration, by rotating the rotary unit at each timing such as toner exhaustion and sequentially switching the developing cartridge to be used, the number of toner replenishment operations for replacing the developing cartridge is reduced, and monochromatic image formation is continued over a long period of time. Can be realized (see, for example, Patent Documents 1 and 2).
JP 2002-351190 A JP 2003-316106 A

  In such an electrophotographic recording type image forming apparatus, it is necessary to maintain the image quality by refreshing the toner contained in the container by stirring or the like. On the other hand, in an image forming apparatus including a rotary unit, when a color image is formed, the developing cartridges that are sequentially opposed to the carrier are sequentially switched. Therefore, the rotation of the rotary unit that performs the switching operation of the developing cartridges is performed. By reversing the top and bottom of the developing cartridge, the toner in the container is once brought together, the contained toner can be refreshed as appropriate, and the image quality can be maintained (see, for example, Patent Document 1).

  However, when a single color image is formed, the same developing cartridge is continuously used. Therefore, when continuously performing an image forming operation (developing operation), the contained toner is stirred (adjusted) during the operation. It is necessary to provide a means for refreshing.

  In addition, in an image forming apparatus including a rotary unit, a partition plate for partitioning a space in which a supply roller rotates is provided in a developing cartridge (container), and toner contained therein is appropriately replenished in the space in which the supply roller operates ( In some cases, the toner supplied to the developing roller does not stay around the supply roller for a long period of time by adjusting, and the image quality is more reliably maintained. Even in this configuration, when forming a color image, the toner stored in the space where the supply roller operates is appropriately replenished by reversing the top and bottom of the developing cartridge as the rotary unit rotates during the switching operation of the developing cartridge. (For example, refer to Patent Document 1).

  However, similarly, when a single color image is formed, the same developing cartridge is continuously used. Therefore, when the image forming operation (developing operation) is continuously performed, the accommodation toner is supplied during the operation. It is necessary to provide means for replenishing the side.

  As described above, as an adjusting means for stirring and replenishing the toner contained in the developing cartridge that forms a single color image, for example, a predetermined amount of image formation is performed at a timing when the toner needs to be adjusted. In the same manner as in the case of forming a color image, it is conceivable to adjust the contained toner appropriately by rotating the rotary unit to reverse the top of the developing cartridge.

  However, when the same developing cartridge is continuously used to form a single color image, the rotary unit is rotated to adjust the toner stored in the developing cartridge. Formation will be interrupted. This accommodated toner adjustment operation needs to be repeated every time a predetermined image formation amount is set as a reference for determining whether or not the accommodation toner adjustment timing has been reached, and this image formation amount is reached. .

  The criterion for determining whether or not to perform the adjustment operation of the stored toner is usually set with a margin, so this adjustment operation has a margin until the actual timing when the stored toner needs to be adjusted. It may be executed regardless. For example, even when the image data recording and forming process is completed by forming an image on another recording medium, the image formation is interrupted and the stored toner adjustment operation is forcibly executed. For this reason, there has been a problem that the image forming speed at which the recording and forming of the image data is completed, that is, the so-called throughput is lowered.

  Therefore, the present invention avoids forcibly entering the adjustment operation by giving flexibility to the execution timing of the adjustment operation for stirring and replenishing the toner contained in the developing cartridge, thereby reducing the so-called throughput. An object is to provide an image forming apparatus that can be improved.

  An image forming apparatus according to a first aspect of the present invention for solving the above-described problems includes a carrier for carrying a toner image in which an electrostatic latent image is formed on the surface and developing the electrostatic latent image, and an electrostatic latent image on the surface of the carrier. A plurality of developing cartridges for forming a toner image to be transferred onto the surface of a recording medium by attaching toner to the image and developing, and storing the plurality of developing cartridges around a rotating shaft and rotating about the rotating shaft And a control unit for controlling the rotation of the rotary unit and the driving of the developing cartridge to form a toner image. The toner is an image forming apparatus that adjusts so that continuous image formation is possible by reversing the top and bottom with the rotation of the rotary unit at the time of image formation. It is characterized in that to adjust the operation of accommodating the toner in the developing cartridge to rotate the rotary unit on the basis of the image forming job information row.

  In the present invention, the timing for starting the adjustment operation of the stored toner is determined not from the processed image forming job but from the image forming job to be processed. Therefore, the adjustment operation of the toner stored in the developing cartridge is not forcibly started regardless of the image forming job to be executed in the future, and it is possible to avoid the image forming operation being interrupted without any darkness.

  According to a second aspect of the image forming apparatus for solving the above-described problem, in addition to the specific matters of the first aspect, the image forming job information is stored in a developing cartridge while being located at a developing position facing the carrier. If the image forming job information to be executed can be completed by the limit consumption amount even if the image forming job information to be executed exceeds a preset margin consumption amount, the developing cartridge is information corresponding to the toner consumption amount. The image forming job is completed without adjusting the contained toner.

  In this invention, when the image forming job is executed, the adjustment operation of the toner contained in the developing cartridge is started every time the consumption information of the toner contained in the developing cartridge used at the developing position reaches the marginal consumption amount. However, if the stored toner necessary for completing the image forming job is equal to or less than the limit consumption, the adjustment operation of the stored toner is omitted. Therefore, the image forming operation can be prevented from being interrupted at a timing that is completed in a short time. When the consumption toner consumption information necessary for the image forming job can be divided below the limit consumption amount, the number of interruptions of the image forming operation can be reduced.

  According to a third aspect of the image forming apparatus for solving the above-mentioned problems, in addition to the specific matters of the first or second aspect, a developing cartridge that contains toner of different colors is housed in the rotary unit. An image, a multicolor image, or a single color image can be formed, and the control unit performs the adjustment operation of the toner contained in the developing cartridge used for forming the single color image by rotating the rotary unit once. It is characterized by this.

  In the present invention, when a single color image is continuously formed without rotating the rotary unit while having a function of forming a color image, the adjustment operation of the toner contained in the developing cartridge to be used is adjusted in accordance with the image forming job information. Be started. Therefore, one rotation of the rotary unit necessary for the adjustment operation of the stored toner is performed without darkness, and the image forming operation is not unnecessarily interrupted.

  According to a fourth aspect of the image forming apparatus for solving the above problem, in addition to the specific matters of the first or second aspect, a plurality of developing cartridges that store toner of the same color are accommodated in the rotary unit. An image can be formed, and the control unit adjusts the toner contained in the developing cartridge used for continuously forming a single color image without rotating the rotary unit. This is performed by rotating the rotary unit at an angle greater than the angle at which the developing cartridge at the position is switched to the adjacent developing cartridge.

  In the present invention, when a monochromatic image is continuously formed without rotating the rotary unit when used as a dedicated machine for forming a monochrome image, the developer cartridge used is matched with the image forming job information. The accommodation toner adjustment operation is started. Therefore, the developing cartridge switching operation necessary for the accommodation toner adjustment operation is performed without any interruption, and the image forming operation is not unnecessarily interrupted.

  According to the present invention, the timing for starting the adjustment operation of the stored toner of the developing cartridge to be used is determined in accordance with, for example, the consumption amount of the stored toner necessary for the image forming job to be processed from here. When the stored toner adjustment operation is started at a certain timing and the image forming job can be completed before the limit, the stored toner adjustment operation is omitted. Therefore, it is possible to avoid the interruption of the image forming operation forcibly regardless of the image forming job by providing flexibility in adjusting the toner contained in the developing cartridge. As a result, it is possible to improve the image forming speed until the image forming job is completed, so-called throughput.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, the best embodiment of the invention will be described with reference to the drawings. 1 to 4 are views showing a first embodiment of an image forming apparatus according to the present invention.

  1 and 2, the image forming apparatus creates and outputs an image such as a character. For example, the image forming apparatus is used by being connected to a personal computer PC, and the control unit 10 connected to the personal computer PC has a paper sheet. By comprehensively controlling the conveyance device 20 and the image recording device 30, an image is formed on a recording sheet (recording medium) and printed out.

  The control unit 10 includes a controller unit 11 and an engine control unit 12 which are constructed on a circuit board mounted in the apparatus main body. These units perform various data processing controls and various parts of the apparatus according to a program prepared in advance. The drive control is executed.

  Briefly, the controller unit 11 executes various processing procedures according to a processing program stored in a memory by a CPU (not shown), thereby various information such as a print command with a printer driver of the personal computer PC. Are received, and image data such as text to be formed by printing on a recording sheet is received and temporarily stored in a memory (not shown). The controller unit 11 is so-called RGB data of red (R), green (G), and blue (B) because the image data (image information signal) received from the personal computer PC is yellow (which can be printed). Y), magenta (M), cyan (C), and black (K) are converted into image data of so-called YMCK data, read out from the memory, and transferred to the engine control unit 12.

  In the engine control unit 12, the CPU 13 receives image data, for example, in units of pages from the controller unit 11 according to a control program stored in the ROM 14, temporarily stores it in the main body memory 15, and uses the RAM 16 as a work area. While exchanging various types of information between the paper transport device 20 and the image recording device 30, an image based on the image data is formed on the recording paper. At this time, when executing this image formation control, the CPU 13 causes each unit of the apparatus to operate optimally by measuring various processing times with a built-in timer function (timer) 13a.

  In FIG. 2, the I / O interface 17 connects the controller unit 11, the sheet transport device 20, the image recording device 30, and the engine control unit 12 so that various types of information can be exchanged. The D / A converter 18 and the A / D converter 19 are configured so that the engine control unit 12 can process various information exchanged between the controller unit 11, the sheet conveying device 20, and the image recording device 30, respectively. A digital signal is converted into an analog signal, or an analog signal is converted into a digital signal.

  In addition to the paper cassette 21, the paper discharge table 22, the pickup roller 23, the transport roller pair 24, the registration roller pair 25, the switching roller pair 26, the paper discharge roller pair 27, and the reverse roller pairs 28 and 29. The intermediate transfer belt 34, which is also a component of the image recording apparatus 30, the transfer roller 35, and the fixing roller pair 36 are constructed. The sheet conveying apparatus 20 separates and conveys a plurality of recording sheets stacked in the sheet cassette 21 one by one and feeds them to the image recording position P of the image recording apparatus 30, thereby After image data such as characters received on one side or both sides is recorded and formed, this image-formed recording paper is carried out of the apparatus and stacked on the paper discharge table 22.

  Briefly, the pickup roller 23 pulls out the recording sheet by rotating against the recording sheet loaded on the lifting plate 21a in the sheet cassette 21 and cooperates with a separating means (not shown). The sheets are separated one by one and fed to the conveyance path f. The conveyance roller pair 24 nips and conveys the recording paper and corrects the skew by abutting the front end against the nip portion of the registration roller pair 25 on the downstream side. The registration roller pair 25 feeds the recording sheet to the image recording position P so as to be synchronized with the operation of the image recording apparatus 30.

  At the image recording position P, the intermediate transfer belt 34 and the transfer roller 35 are conveyed by rotating while sandwiching the fed recording paper, and the image is recorded and formed on one side of the recording paper. . Further, the fixing roller pair 36 rotates while sandwiching the recording paper, thereby conveying the recording paper further downstream and fixing the image on the recording paper.

  Thereafter, the switching roller pair 26 and the discharge roller pair 27 carry the recording paper from the fixing roller pair 36 onto the discharge table 22 and stack it. As a result, the recording sheet is fed to the image recording formation position P by the image recording apparatus 30 with one side being the image recording formation surface, formed on one side, and then discharged onto the discharge table 22. The

  At this time, when the engine control unit 12 has instructed the duplex control mode for forming an image on both sides of the recording paper, the paper transport device 20 records the paper discharge roller pair 27 carried onto the paper discharge table 22. After temporarily stopping at a position where the trailing edge of the sheet is sandwiched, the recording sheet on which an image is recorded on one side is sent out to the reverse path r by being reversely driven together with the switching roller pair 26.

  Thereafter, the reversing roller pair 28, 29 sandwiches the recording paper and passes and conveys the recording paper in the reversing path r, so that the rear end side at the time of image formation on one side is reversed to the front side. The recording paper having the reversed image is fed again to the conveyance path f and delivered to the registration roller pair 25. Thus, the recording sheet is fed again to the image recording position P by the image recording device 30 with the other side (one side where no image is recorded) as the image recording surface, and image formation is performed on both sides. Then, the paper is discharged onto the paper discharge table 22.

  On the other hand, the image recording apparatus 30 includes an exposure unit 31, a photosensitive cartridge 32, a developing rotary unit 33, an intermediate transfer belt 34, a transfer roller 35, and a fixing roller pair 36. The image recording apparatus 30 records received image data such as characters on one side or both sides of a recording sheet conveyed by the sheet conveying apparatus 20 and fed to the image recording position P by an electrophotographic method. Form.

  Briefly, the exposure unit 31 selectively irradiates the surface of the photosensitive drum 32a in the photosensitive cartridge 32 with laser light based on the image data received by the laser beam scanning device (polygon mirror) 31a provided therein. By performing exposure scanning, an electrostatic latent image based on the image data is formed (image formation) on the surface of the photosensitive drum 32a. The developing rotary unit 33 develops the electrostatic latent image on the photosensitive drum 32a with yellow (Y), cyan (C), magenta (M), and black (K) toners for each color. 37y, 37m, 37c, and 37k) are housed therein, and toner that accommodates the developing cartridge 37 corresponding to the image data for forming the electrostatic latent image is attached to the photosensitive drum 32a. As a result, the electrostatic latent image is developed with toner.

  For example, in the case of a monochrome image, the intermediate transfer belt 34 receives a toner image with toner of black (K) formed on the photosensitive drum 32a, and transfers the toner image (toner image) onto the recording paper on the belt surface. ). In addition, in the case of a color image, the intermediate transfer belt 34 sequentially forms toner images with yellow (Y), cyan (C), and magenta (M) toner formed on the photosensitive drum 32a (the order is the same). (Not limited) A color toner image that is received in a superimposed manner and transferred onto a recording sheet is formed and held on the belt surface. The transfer roller 35 presses (nips) the recording paper fed between the intermediate transfer belt 34 (image recording position P) and sandwiches and conveys the toner image, thereby recording the toner image. Transfer to paper. Needless to say, the toner is transferred from the developing cartridge 37 to the recording sheet via the photosensitive drum 32a and the intermediate transfer belt 34 in accordance with the bias voltage between the members.

  The fixing roller pair 36 heats and presses the recording paper that has been transferred from the image recording position P to which the toner image has been transferred, and fixes the toner image, and further nipping and conveying the recording paper further downstream. . As a result, a monochrome image or a color image based on the received image data is recorded and fixed (fixed) on one side or both sides of the recording paper. By repeating such operations, images are continuously recorded on a plurality of sheets. Can be formed.

  Note that the toner remaining on the photosensitive drum 32a after being transferred to the intermediate transfer belt 34 is discharged and collected by a cleaning device (not shown), and thereafter the toner is received from the developing cartridge 37 of the developing rotary unit 33 by a charger. Charged to the potential to be attached. Similarly, the intermediate transfer belt 34 is discharged and charged, and toner transfer (attachment) and recovery are repeated. Further, the toner scattered at the time of collection is collected by a filter 39 a attached to the exhaust duct 39 when the suction fan 38 sucks the apparatus main body side through the exhaust duct 39.

  In the developing rotary unit 33, as shown in FIG. 3, a developing cartridge 37 that develops toner on the electrostatic latent image on the surface of the photosensitive drum 32a is partitioned by a partition frame 33b that rotates about a rotating shaft 33a. It is configured by being housed (mounted) in a storage position. The developing rotary unit 33 is rotated around the rotation shaft 33 a based on a print command including image data from the personal computer PC received by the CPU (control means) 13 of the engine control unit 12 via the controller unit 11. As a result, the developing cartridge 37 facing the photosensitive drum 32a is switched to develop the toner image to be transferred to one side or both sides of the recording paper to form an image.

  For example, the image forming apparatus stores developing cartridges 37y, 37m, 37c, and 37k that store yellow (Y), cyan (C), magenta (M), and black (K) toners in the developing rotary unit 33. At the same time, the developing rotary unit 33 is rotated to switch the developing cartridge 37 that develops the electrostatic latent image on the photosensitive drum 32a so as to superimpose or select the respective color-accommodating toners. It can be used as an apparatus capable of forming up to a monochrome image.

  Specifically, the developing cartridge 37 includes a container 37a, a developing roller 37b, a supply roller 37d, and a partition plate 37e. The container 37a is formed in a similar shape so as to be housed in each housing space (position) partitioned by the partition frame 33b of the developing rotary unit 33, and stores the toner. The developing roller 37b is rotatably supported on the outer peripheral side of the container 37a that is separated from the rotation shaft 33a of the developing rotary unit 33, and causes the toner delivered from the supply roller 37d to adhere to the opposing photosensitive drum 32a. The supply roller 37d is rotatably supported by the container 37a so as to be adjacent to the developing roller 37b on the rotating shaft 33a side of the developing rotary unit 33, and wears and charges surrounding toner by rotating in pressure contact with the developing roller 37b. To supply. The partition plate 37e is installed so as to surround the supply roller 37d, and partitions the toner storage space in the container 37a in a state where the space on the rotating shaft 33a side communicates with the upper portion in the rotation direction of the installation space of the supply roller 37d. Yes.

  With this configuration, the developing cartridge 37 supplies the toner in the space on the outer peripheral side of the container 37a partitioned by the partition plate 37e to the developing roller 37b in which the supply roller 37d rotates by pressure. Further, when the developing rotary unit 33 rotates by 90 degrees counterclockwise in FIG. 3 and rotates 180 degrees, the developing cartridge 37 partitions the accommodation toner on the rotating shaft 33a side and the supply roller 37d side of the container 37a. After being put together at the upper part of the plate 37e (lower part in FIG. 3), the toner contained in the container 37a is stirred and refreshed by rotating 90 degrees at a time, and the contained toner can be supplied to the developing roller 37b. Collect on the supply roller 37d side. That is, in the developing cartridge 37 mounted on the developing rotary unit 33 rotating in this manner, the stored toner is replenished while being agitated toward the supply roller 37d by the rotation, and therefore an adjustment operation for agitating and replenishing the accommodated toner is performed. An adjustment device (so-called agitator device or auger device) for performing the operation can be omitted as appropriate. However, in the case where the developing device 37 is omitted, the developing cartridge 37, for example, at least before the toner supplied to the developing roller 37b runs out of the periphery of the supply roller 37d, as described later, Development rotary unit when the amount of toner detected exceeds the preset value, such as the number of dots, the development operation (image formation) time to be accumulated, the number of developments to be accumulated, or the actually measured remaining amount of toner It is necessary to rotate toner 33 to perform toner replenishment / stirring operation.

  The developing cartridge 37 includes a nonvolatile memory 42 and a developing side connector 43, and a control side connector 44 is disposed on the developing rotary unit 33 side. The nonvolatile memory 42 rewritably stores various information such as the color of toner to be stored, the date of manufacture, and the amount of consumption, along with identification information such as a manufacturing number. The development-side connector 43 is connected to the nonvolatile memory 42 and reads and rewrites information stored therein. The control-side connector 44 is arranged so as not to move to the outer periphery of the developing rotary unit 33, and exchanges various types of information by contactless communication when facing the developing-side connector 43 of any of the developing cartridges 37. As a result, the engine control unit 12 of the control unit 10 appropriately grasps various information such as toner color information of the developing cartridge 37 together with the presence or absence and position of the developing cartridge 37 stored in the storage position of the developing rotary unit 33. Thus, image forming control including optimal switching control of the developing cartridge 37 is executed.

  Specifically, the CPU 13 of the engine control unit 12 executes various control operations according to the control program in the ROM 14 after the power is turned on. When the power is turned on or when the developing cartridge 37 is replaced, the connectors 43 and 44 are used. By performing non-contact communication via the, the presence / absence of the developing cartridge 37 at the storage position of the developing rotary unit 33 is held (stored) in the main body memory 15. Further, the CPU 13 sequentially reads out various information written in the nonvolatile memory 42 of each developing cartridge 37 via the connectors 43 and 44, and position information, toner color information and consumption for each developing cartridge 37. The amount (remaining amount) is stored in the main body memory 15. Further, the CPU 13 writes various information such as the amount of toner consumed by the image formation into the nonvolatile memory 42 of each developing cartridge 37 via the connectors 43 and 44 during the image forming operation or after the image formation is completed. rewrite.

  At this time, the CPU 13 has set the developing cartridges 37y, 37m, 37c, and 37k containing toners of yellow (Y), cyan (C), magenta (M), and black (K) in the developing rotary unit 33. When the image data for forming a color image is sent from the controller unit 11 when the controller unit 11 is grasped, the developing rotary unit 33 is rotated in accordance with the image data, so that the development facing the photosensitive drum 32a is performed. By sequentially switching the developing cartridges 37y, 37m, 37c, and 37k at the positions, a color image is recorded and formed on one side or both sides of the recording paper. In other words, each color toner developing cartridge 37 mounted on the developing rotary unit 33 is switched and operated whenever it receives a print command of image data of a color image. Thus, in the developing cartridges 37y, 37m, 37c, and 37k, the accommodated toner is appropriately replenished to the supply roller 37d that supplies the accommodated toner to the developing roller 37b as the developing rotary unit 33 rotates.

  On the other hand, when image data for forming a monochrome image is sent from the controller unit 11, the CPU 13 switches the development position facing the photosensitive drum 32a to the development cartridge 37k and fixes the monochrome image continuously. Recording is continuously performed on one or both sides of the recording paper. At this time, the CPU 13 adjusts the toner contained in the developing cartridge 37k by rotating the rotary unit once based on the contents of the image forming job information for recording and forming the received image data on the recording paper. For example, the CPU 13 compares the consumption amount of black (K) toner when executing the recording formation (image formation) of the image data with the margin consumption amount and the limit consumption amount set in the main body memory 15 in advance. Thus, the timing for adjusting the toner contained in the developing cartridge 37k is determined by rotating the developing rotary unit 33 once.

  Here, the surplus consumption amount is determined from the actual limit toner consumption amount until the toner supplied to the developing roller 37b disappears from the periphery of the supply roller 37d after the replenishment operation of the stored toner is performed by one rotation of the rotary unit. The amount of toner consumption has secured a margin (sufficient safety) by subtracting a fixed amount. For example, image formation on 40 recording sheets is set in the main body memory 15. Further, the limit consumption is a marginal toner consumption obtained by subtracting a predetermined amount from the actual limit toner consumption so as to reduce some margin from the margin consumption. Image formation on 45 recording sheets including 5 sheets is set in the main body memory 15.

  For example, as shown in the flowchart of FIG. 4, when the CPU 13 receives a print command for monochrome image data from the controller unit 11 (step S11), the developing rotary unit 33 is rotated to place the developing cartridge 37k on the photosensitive drum 32a. The toner consumption amount (the number of images formed on the recording paper) stored in the main body memory 15 is reset (step S12). At this time, when the developing cartridge 37k is already at the developing position, the developing rotary unit 33 is rotated once to perform an adjustment operation such as replenishing the toner contained in the developing cartridge 37k, and the toner in the main body memory 15 Reset consumption. If the warm-up is short and the printing process can be started quickly, the toner consumption in the main body memory 15 is added without rotating the developing rotary unit 33 and resetting. Thus, it is more advantageous to improve the so-called throughput if the adjustment operation of the stored toner is omitted. However, in this case, it is necessary to consider the amount of toner consumed by the previous printing process stored in the main body memory 15.

Next, the number of recording sheets on which the received image data is printed is the remainder after repeated image formation on 40 recording sheets (hereinafter sometimes simply referred to as the number of sheets) with a marginal consumption (divided by 40 sheets) (The remainder of the time) is within the limit consumption of 45 sheets, in other words, whether the number of printed sheets S satisfies the following equation (step S13).
40 × n (sheets) <S (sheets) <40 × n + 5 (sheets) n: When the above equation is satisfied, up to [40 × (n−1)] sheets for every 40 sheets of surplus consumption After performing the adjusting operation of stirring and replenishing the toner stored in the developing cartridge 37k by rotating the developing rotary unit 33 once, the adjusting operation of the (40 × n) th stored toner is not performed, and the limit consumption amount is reduced. Image formation control is selected and set so as to continue the printing process that ends up to 45 sheets (step S14). That is, in this case, the developing rotary unit 33 rotates (n−1) and does not rotate n times.

  If the above equation is not satisfied, the toner contained in the developing cartridge 37k is agitated and replenished by rotating the rotary unit once for every 40 sheets of surplus consumption without setting the limit consumption as usual. The image forming control for performing the adjusting operation is selected and set (step S15). That is, in this case, the developing rotary unit 33 rotates n times.

  After setting the consumption amount at the timing of adjusting the stored toner, drive control of the paper conveying device 20 and the image recording device 30 for printing the received image data is started, and an image is printed on one or both sides of the recording paper. Form (step S16).

  Next, every time the printing process for each recording sheet is completed, it is confirmed whether or not the printing process for the received image data is completed (step S17). Exit.

  If it has not been completed, it is checked whether the amount of toner consumption has been set and whether or not the surplus consumption of 40 sheets has been exceeded (step S18). If not, the process returns to step S16 as it is, and the printing process using the developing cartridge 37k is continued without performing the adjustment operation of the stored toner by the rotation of the developing rotary unit 33. Further, when the amount of stored toner exceeds 40 sheets of recording paper, the limit consumption amount is set, and at the same time, when the number of rotations of the developing rotary unit 33 is nth, the process proceeds to step S16. Returning, the printing process using the developing cartridge 37k is continued without performing the adjustment operation of the stored toner by one rotation of the developing rotary unit 33.

  On the other hand, if the amount of toner consumed exceeds 40 sheets and at the same time the number of rotations of the developing rotary unit 33 is less than n, the developing rotary unit 33 is turned on regardless of whether or not the limit consumption amount is set. After adjusting the toner consumption amount stored in the main body memory 15 (step S19) after performing the adjusting operation of stirring and replenishing the toner stored in the developing cartridge 37k by one rotation, the process returns to step S16 to return to the developing cartridge 37k. Restart the printing process using.

  Therefore, before executing the image forming job for printing the received image data on the recording paper, the consumption amount of the stored toner necessary for the printing process is confirmed, and the image forming job is performed without adjusting the stored toner. Can be forcibly prevented from interrupting the rotation of the developing rotary unit 33 in the image forming job until the image forming job can be completed, and the image forming job can be completed promptly without being interrupted unnecessarily. .

  As described above, in the present embodiment, when the developing cartridges 37y, 37m, 37c, and 37k are attached and used so that a color image or a monochrome image can be formed, the monochrome and the developing cartridge 37k remain in the developing position. When images are continuously formed, an adjustment operation of the toner contained in the developing cartridge 37k is started by one rotation of the developing rotary unit 33 according to the consumption amount of the toner necessary for processing the image forming job. Determine the timing (necessity of adjustment operation). As a result, if the image forming job can be completed by continuing the printing process while repeating the stored toner adjustment operation with sufficient timing, the stored toner adjustment operation can be passed. Therefore, the timing for adjusting the toner contained in the developing cartridge 37k can be accommodated to avoid interruption of the image forming job, and the image forming job can be completed quickly to achieve the image forming speed (so-called throughput). Can be up.

  Next, FIG. 5 is a diagram showing a second embodiment of the image forming apparatus according to the present invention. In addition, since this embodiment is configured in substantially the same manner as the above-described embodiment, the features will be described using the drawings (the same applies to other embodiments described below).

  1 to 3, the main body memory 15 of the engine control unit 12 is set with the number of grams, which is the consumption amount of stored toner used at the time of image formation, as the marginal consumption amount and the limit consumption amount of the image forming job information. For example, 10 g is added as a margin consumption of the toner before the toner supplied to the developing roller 37 b runs out of the surroundings of the supply roller 37 d, and 11 g is obtained by adding 1 g to the margin consumption. Set. Here, it is needless to say that the margin consumption etc. are not limited to these parameters as the number of recording sheets corresponding to the toner consumption is set in the main body memory 15 in the first embodiment. However, for example, a count value by a toner counter, the number of dots of an image, a developing operation (image formation) time to be integrated, or an actually measured remaining amount of toner may be employed.

  Then, as shown in the flowchart of FIG. 6, the CPU 13 of the engine control unit 12 receives a print command for image data of a monochrome image, as in the first embodiment, and the developing cartridge 37k by the rotation of the developing rotary unit 33. At the same time, the toner consumption (grams) stored in the main body memory 15 is reset (steps S11 and S12).

After this, whether or not the accommodation toner necessary for printing the received image data is less than the limit consumption 11g after the remainder of the image formation of the allowance consumption 10g is repeated (the remainder when dividing by 10g). In other words, confirm whether the expected consumption s satisfies the following equation (step S23),
10 × n (g) <s (g) <10 × n + 1 (g) n: When the above equation is satisfied, the marginal consumption amount until the consumption amount of the toner accommodated is [10 × (n−1)] g. After the adjusting operation of stirring and replenishing the toner stored in the developing cartridge 37k by rotating the developing rotary unit 33 once every 10 g of the toner, the adjusting operation of the (10 × n) g stored toner is not performed. It is selected and set so as to continue the printing process that ends up to 11 g of the limit consumption (step S24). That is, in this case, the developing rotary unit 33 rotates (n−1) and does not rotate n times.

  If the above equation is not satisfied, the toner stored in the developing cartridge 37k is stirred and replenished by rotating the rotary unit once for every 10 g of the surplus consumption without setting the limit consumption as usual. The image forming control for performing the adjustment operation is selected and set (step S25). That is, in this case, the developing rotary unit 33 rotates n times.

  After the setting of the consumption amount for performing the adjustment operation of the accommodated toner, as in the first embodiment, the drive control of the sheet conveying device 20 and the image recording device 30 for printing the received image data is started and the recording is performed. Until the printing process on one or both sides of each sheet is completed, the toner adjustment operation by one rotation of the developing rotary unit 33 is repeated, and the printing process using the developing cartridge 37k is continued (steps S16 and S17). ).

  At this time, when the amount of toner contained in the developing cartridge 37k does not exceed 10 g, or the amount of toner contained exceeds 10 g, the limit consumption is set, and at the same time, the developing rotary unit Even when the number of rotations 33 is the nth, the process returns to step S16 as it is, and the printing process using the developing cartridge 37k is continued without performing the toner adjustment operation by one rotation of the developing rotary unit 33. To do.

  On the other hand, if the consumption amount of the stored toner exceeds 10 g and at the same time the number of rotations of the developing rotary unit 33 is less than n, the developing rotary unit 33 is rotated once to store the stored toner in the developing cartridge 37k. After performing the adjusting operation of stirring and replenishing and resetting the toner consumption amount stored in the main body memory 15 (step S19), the process returns to step S16 to restart the printing process using the developing cartridge 37k.

  As described above, also in this embodiment, the same operational effects as those of the first embodiment can be obtained, and the developing cartridge 37k can be rotated once by the developing rotary unit 33 based on the actual consumption amount of the stored toner. Since the accommodation toner adjustment operation is performed, the marginal consumption amount and the limit consumption amount can be set more accurately, and the drive control can be performed precisely.

  Next, FIG. 6 is a diagram showing a third embodiment of the image forming apparatus according to the present invention.

  1 to 3, in the main body memory 15 of the engine control unit 12, as in the first and second embodiments described above, together with image formation on 40 recording papers as a margin consumption of image formation job information. In addition, 10 g of the consumption amount of the accommodated toner used at the time of image formation is set, and 11 g of the consumption amount of the accommodated toner is set as the limit consumption amount together with the image formation on 45 recording sheets.

  In this embodiment, the CPU 13 of the engine control unit 12 determines and sets the timing for adjusting the toner contained in the developing cartridge 37k by the rotation of the developing rotary unit 33. In parallel with this process, it is determined whether or not the adjustment operation of the toner contained in the developing cartridge 37k is necessary.

  Specifically, as shown in the flowchart of FIG. 6, as in the first and second embodiments, the CPU 13 receives a print command for monochrome image data and develops the developing cartridge by the rotation of the developing rotary unit 33. Simultaneously with the switching of 37k, the toner consumption (the number of recording sheets and the number of grams) stored in the main body memory 15 is reset (steps S11 and S12).

  After that, before setting the timing (toner consumption) for adjusting the accommodation toner, drive control of the paper transport device 20 and the image recording device 30 for printing the received image data is started, and the recording paper is loaded. An image is formed on one side or both sides (step S33).

  In this embodiment, each time the printing process for each recording sheet is completed, whether or not the toner consumption amount does not require the supply toner 37d in the developing cartridge 37k to be replenished, for example, continuously. It is confirmed whether the cumulative number of images to be formed (printed) on the recording paper is 40 or less (AND condition), and the cumulative amount of actual toner consumption based on the number of dots of the image is 10 g or less (step) S34). In the present embodiment, the determination is made with an AND condition that satisfies both conditions, but it is needless to say that the determination is based on an OR condition that satisfies one of the conditions. You may do it.

  If the image formation of the image data so far does not satisfy one of the conditions, one sheet is added to the cumulative number of continuous prints and the actual consumption amount is added to the cumulative toner consumption amount (step). S35), it is confirmed whether or not the printing process of the received image data has been completed (step S36). If the image data printing process has been completed, the image forming control is terminated as it is. If not, the process returns to step S33 to adjust the accommodation toner by the rotation of the developing rotary unit 33. The printing process using the developing cartridge 37k is continued without performing the operation.

  On the other hand, if the image formation of the image data so far satisfies both conditions, the number of unprocessed print sheets in the received image data and the need for image formation on the recording sheet are expected. The amount of consumed toner is calculated and acquired (step S37).

  Next, when the estimated toner consumption is 1 g or less of the difference between the marginal consumption and the limit consumption, and the number of unprocessed prints is 5 or less, the process returns to step S33 and the developing rotary unit 33 is continued. The printing process using the developing cartridge 37k is continued without performing the adjustment operation of the accommodated toner by the rotation (steps S38 and S39).

  On the other hand, the expected toner consumption required for printing the unprocessed image data is not less than 1 g of the difference between the margin consumption and the limit consumption, or the number of unprocessed prints is not less than 5. In this case, the developing rotary unit 33 is rotated once to perform an adjusting operation for stirring and replenishing the toner contained in the developing cartridge 37k, and the cumulative value of the number of continuous print sheets and the toner consumption stored in the main body memory 15 After resetting (toner consumption) (steps S40 and S41), the process returns to step S33 to restart the printing process using the developing cartridge 37k.

  Therefore, each time the received image data is printed on the recording paper, the amount of toner consumed for the image forming job to be executed can be confirmed, and the image forming job can be completed without adjusting the contained toner. Until this time, it is possible to avoid the forced rotation of the developing rotary unit 33 from interrupting the image forming job, and the image forming job can be completed quickly without being interrupted unnecessarily.

  As described above, in this embodiment, the same operational effects as those of the above-described embodiment can be obtained, and development by one rotation of the developing rotary unit 33 can be performed based on the number of recording sheets to be printed and the actual consumption amount of stored toner. Since the adjustment operation of the toner contained in the cartridge 37k is performed, the drive control can be precisely performed using the margin consumption and the limit consumption with higher reliability.

  Here, in the above-described embodiment, the developing cartridges 37y, 37m, 37c, and 37k that contain yellow (Y), cyan (C), magenta (M), and black (K) toner are stored in the developing rotary unit 33. Although the case where it is stored and used so that a single color image can be formed from a color image on a recording sheet will be described, the present invention is not limited to this. The present invention can also be applied to a case where, for example, four developing cartridges 37k containing black (K) toner are accommodated in the developing rotary unit 33 and used as a dedicated machine for forming a monochrome image. Specifically, the development rotary 37 is positioned at the timing when one of the development cartridges 37k is positioned at the development position facing the photosensitive drum 32a and the adjustment operation for stirring and replenishing the toner contained in the development cartridge 37k becomes necessary. The present invention can be applied when image formation control is performed so that the unit 33 is rotated 90 degrees or more.

  In the above-described embodiment, it is determined whether the adjustment operation of the toner contained in the developing cartridge 37k by the rotation of the developing rotary unit 33 is necessary at the final timing, and the adjustment operation of the toner is executed. However, it is not limited to this. For example, in the image formation control of received image data, the number of adjustment operations is less when the accommodation toner adjustment operation is performed for each limit consumption amount than when the accommodation toner adjustment operation is performed for each margin consumption amount. Alternatively, the limit consumption amount can be used as the adjustment operation timing of the stored toner. In this case, it goes without saying that the set consumption amount of the adjustment operation timing of the stored toner may be averaged so as to have a margin as much as possible.

  Furthermore, in the above-described embodiment, a case where image forming job information (toner consumption) of image data from a personal computer PC is processed individually will be described as an example, but the present invention is not limited to this. For example, when receiving image data for each page or image forming job information of separate image data from the personal computer PC, adjusting the toner to be accommodated as in the third embodiment while connecting the image forming job information. You may enable it to reset the timing which performs operation | movement.

  Although one embodiment of the present invention has been described so far, it is needless to say that the present invention is not limited to the above-described embodiment, and may be implemented in various forms within the scope of the technical idea.

1 is a perspective front view illustrating a schematic overall configuration of a first embodiment of an image forming apparatus according to the present invention. It is a related block diagram explaining the drive control. FIG. 6 is a transparent front view showing a developing rotary unit that houses the developing cartridge. 4 is a flowchart illustrating the image formation control. It is a figure which shows 2nd Embodiment of the image forming apparatus which concerns on this invention, and is a flowchart explaining the image formation control. It is a figure which shows 3rd Embodiment of the image forming apparatus which concerns on this invention, and is a flowchart explaining the image formation control.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Control unit 11 Controller part 12 Engine control part 13 CPU
14 RAM
15 Main body memory 16 RAM
20 Paper transport device 30 Image recording device 31 Exposure unit 32a Photosensitive drum 33 Development rotary unit 33a Rotating shaft 34 Intermediate transfer belt 35 Transfer roller 36 Fixing roller pair 37y, 37m, 37c, 37k Development cartridge 37a Container 37b Development roller 37d Supply roller 37e Partition plate 42 Non-volatile memory 43 Development side connector 44 Control side connector P Recording position

Claims (4)

A surface of the recording medium formed by forming a latent electrostatic image on the surface and carrying a toner image obtained by developing the latent electrostatic image, and developing the electrostatic latent image on the surface of the carrier with toner attached thereto A plurality of developing cartridges for forming a toner image to be transferred to the toner cartridge, and the plurality of developing cartridges are housed around a rotation shaft and rotated around the rotation shaft so that any one of the developing cartridges faces the surface of the carrier. A rotary unit, and a control means for controlling the rotation of the rotary unit and the driving of the developing cartridge to form a toner image,
The toner contained in the developing cartridge is an image forming apparatus that adjusts so that continuous image formation is possible by reversing the top and bottom with the rotation of the rotary unit during image formation,
The control unit rotates the rotary unit based on information on the image forming job to be executed, and adjusts the toner contained in the developing cartridge. The image forming job information is information corresponding to the consumption amount of toner contained in the developing cartridge while being located at the developing position facing the carrier.
If the image forming job information to be executed can be completed by the limit consumption amount even if the image forming job information to be executed exceeds the preset margin consumption amount, the control unit does not perform the adjustment operation of the toner contained in the developing cartridge. The image forming apparatus according to claim 1, wherein the image forming job is completed. In the rotary unit, a developing cartridge that stores toner of different colors is stored, and a color image, a multicolor image, or a single color image can be formed.
3. The image forming apparatus according to claim 1, wherein the control unit performs an adjustment operation of toner contained in a developing cartridge used when forming a monochrome image by rotating the rotary unit once. 4. . In the rotary unit, a plurality of developing cartridges that store toner of the same color are stored so that a single color image can be formed.
The control means adjusts the toner contained in the developing cartridge used when continuously forming a single color image without rotating the rotary unit, and develops the developing cartridge at the developing position adjacent to the carrying member adjacent to the developing cartridge. The image forming apparatus according to claim 1, wherein the image forming apparatus performs the rotation by rotating the rotary unit at an angle larger than an angle for switching to the cartridge.

Images