JP2008112061A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which has a short printing waiting time due to confirmation of process cartridge attachment. <P>SOLUTION: In the image forming apparatus for printing an image comprising a plurality of colors by mounting a plurality of process cartridges having different developing colors thereon, developing colors required for outputting image data for which printing request is received are confirmed, and it is confirmed whether the process cartridges having the developing colors required for output are attached. When all the process cartridges having the developing colors required for output are attached, the image forming operation is immediately started. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a multicolor image forming apparatus.

  In a conventional color image forming apparatus, a process cartridge for each color is generally configured to be individually detachable to a developing unit for forming a multicolor image with a plurality of developers. The developing unit checks whether or not the process cartridges for each color are mounted, and prohibits development when all the process cartridges are not mounted.

  The confirmation of the mounting state of the process cartridge by the developing unit is made by determining that the process cartridge is mounted when the CPU of the developing unit communicates with the memory of the process cartridge and there is a response from the memory. In many cases, the memory of each process cartridge is connected to one bus extending from the CPU of the developing unit in order to reduce the cost of the image forming apparatus. In such an image forming apparatus, the CPU of the developing unit exchanges data by designating the ID of the process cartridge. In the process cartridge mounting confirmation process, it is necessary to sequentially check whether there is a response to the transmitted ID, and there is a problem that it takes time to complete the process.

In Patent Documents 1 to 3, when the print data is black and white data, the mounting confirmation of only the black process cartridge is performed. When the printing data is color data, the mounting confirmation of all the process cartridges is performed. A technique for determining whether printing is possible is described. That is, even if these techniques are used, when color data is printed, the image forming operation cannot be started until all process cartridges are confirmed to be mounted.
JP 2005-249971 A JP 2005-352375 A JP 2005-352376 A

  In view of the above problems, an object of the present invention is to provide an image forming apparatus with a short print waiting time by confirmation of process cartridge mounting.

  In order to solve the above-described problems, an image forming apparatus according to the present invention is an image forming apparatus that is capable of printing an image having a plurality of colors by mounting a plurality of process cartridges having different development colors. Confirm the development color necessary for data output, confirm whether the process cartridge of the development color necessary for the output is installed, and if all the process cartridges of the development color necessary for the output are installed, Assume that the image forming operation starts immediately.

  According to this configuration, priority is given to confirming the installation of process cartridges necessary for printing, and if the process cartridges necessary for printing are ready, the image forming operation is started. There is no need to wait until the print start time is shortened.

  In the image forming apparatus of the present invention, the plurality of process cartridges are all connected on the same communication line, and when a color code indicating a developing color of the process cartridge is received from the communication line, a response signal is sent to the communication line. May be returned.

  According to this configuration, the configuration for connection to the process cartridge is simple, and the image forming apparatus is inexpensive. Further, in such a configuration in which the communication time is long, the effect of reducing the waiting time until printing is great.

  Further, in the image forming apparatus of the present invention, when predetermined conditions are satisfied, the presence / absence of all the process cartridges is confirmed in a predetermined order. When a print request is received, the presence / absence of the mounting is already confirmed. The process cartridge that has been used may not be checked again for installation.

  According to this configuration, even if there is no print request, the process cartridge is confirmed to be mounted as appropriate, and when the print request is received, the reconfirmation of the process cartridge whose mounting has been confirmed is omitted until printing is possible. The waiting time can be shortened.

  In the image forming apparatus of the present invention, toner replenishment control may be performed from the process cartridge that is confirmed to be mounted among a plurality of process cartridges.

  In the image forming apparatus of the present invention, the development output potential adjustment control may be performed from the process cartridge that has been confirmed to be mounted among a plurality of process cartridges.

  According to the present invention, it is possible to determine a color necessary for data output from print data, preferentially check a process cartridge of a necessary color, and start an image forming operation early.

Embodiments of the present invention will now be described with reference to the drawings.
FIG. 1 shows an image forming apparatus 1 according to a first embodiment of the present invention. The image forming apparatus 1 can be equipped with four process cartridges 2 for forming toner images of respective colors of yellow (Y), magenta (M), cyan (C), and black (K). 2 is formed to form a toner image of each color, and a toner image of each color is formed on the intermediate transfer belt 3 by superimposing and transferring the toner image of each color, and a toner image transferred to the intermediate transfer belt 3 Are transferred to the recording sheet S by electrostatic force, a fixing device 6 for fixing the toner image by heating the recording sheet S, and yellow, magenta, cyan, and black toners on the process cartridges 2 respectively. And four toner cartridges 7 to be supplied.

  Each process cartridge 2 includes a rotating drum-shaped photoconductor 8, a charger 9 for charging the photoconductor 8, an exposure device 10 for exposing the charged photoconductor 8 to form an electrostatic latent image, and A developing unit 11 that forms a toner image by attaching toner to the electrostatic latent image, a primary transfer roller 12 that transfers the toner image formed on the photosensitive member 9 to the intermediate transfer belt 3 by electrostatic force, and the photosensitive member 9 And a cleaner 13 for scraping off the toner on the surface.

  The transfer belt 3 is stretched around a driving roller 14 that is rotationally driven, a driven roller 15, and a tension roller 16 that applies tension, and is rotated by the driving roller 14 in the direction of the arrow. Further, the image forming apparatus 1 includes a cleaner unit 17 that removes toner remaining on the surface of the transfer belt 3.

  The recording paper S is supplied to the paper supply tray 18, fed one by one by the supply roller 19, transported to the secondary transfer roller 5 by the transport roller 20, passes through the fixing device 6, and is discharged by the paper discharge roller 21. 22 is discharged. A plurality of paper feed trays 18 and paper feed rollers 19 may be provided.

  In addition, the image forming apparatus 1 includes a controller 23 that performs the operation of each component and processing of an image signal to be formed.

  FIG. 2 shows in detail the configuration related to the control of the developing unit 4 of the image forming apparatus 1. The developing unit 4 includes a CPU 24 that communicates with the controller 23, a drive system 25 that operates according to instructions from the CPU 24, drives each process cartridge 2, and a nonvolatile memory 26 that the CPU 24 can read and write.

  Each process cartridge 2 has a non-volatile memory 27, and each non-volatile memory 27 is connected to the same communication line extending from the CPU 24 when the process cartridge 2 is attached to the developing unit 4. Thus, communication with the CPU 24 becomes possible.

  The non-volatile memory 26 of the developing unit 4 includes an unmounted bit indicating that each process cartridge 2 is not mounted, a priority bit indicating that each process cartridge 2 is necessary for image formation, and each process cartridge. An area for storing a detection execution bit indicating that the mounting confirmation has been completed for each of 2 is secured.

  When the CPU 24 communicates with each non-volatile memory 27, in order to specify which non-volatile memory 27 to communicate with, only one of the non-volatile memories 27 of each color as shown in FIG. A reset signal that also serves as a color code to respond to is transmitted.

  As shown in the figure, the reset signal for each color is a pulse signal having a different width depending on the development color. Each non-volatile memory 27 returns a response signal to the CPU 24 via a communication line only when it receives a reset signal that matches its development color. In the present embodiment, the potential of the communication line is normally maintained at the HIGH level, and the LOW level is transmitted as a signal.

  Next, the flow of control by the CPU 24 in the developing unit 4 when the image forming apparatus 1 performs image formation will be described.

  FIG. 4 shows the process cartridge 2 implemented by the developing unit 4 when the image forming apparatus 1 is turned on and when a predetermined condition such as the energy saving mode or the return from the cover open condition is satisfied. The flow of a mounting confirmation process is shown.

  In this normal mounting confirmation process, the CPU 24 of the developing unit 4 first resets all detection execution bits in the nonvolatile memory 26. Thereafter, for example, as shown in the figure, the CPU 24 sequentially confirms the mounting of the Y process cartridge 2, the M process cartridge 2, the C process cartridge 2, and finally the K process cartridge 2. To do. This mounting confirmation is determined by whether the CPU 24 transmits a reset signal of the development color to be confirmed of any of the four process cartridges 2 and whether there is a response from the nonvolatile memory 27 of the process cartridge 2. In this mounting confirmation, the ID or the like may be returned from each process cartridge 2 to acquire not only the presence / absence of mounting but also the information of each process cartridge 2.

  When any of the process cartridges 2 is not attached, the CPU 24 sets an unattached bit corresponding to the unattached process cartridge 2 in the nonvolatile memory 26 of the developing unit 4. In addition, the CPU 24 sets a detection execution bit corresponding to the process cartridge 2 that has been confirmed to be installed or not.

  When the CPU 24 finishes mounting all the process cartridges 2 and any of the unmounted bits are set, the CPU 24 notifies the controller 23 to that effect. Receiving the notification that the unmounted bit is set, the controller 23 displays a warning on the display device (not shown) of the image forming apparatus 1 and prompts the user to confirm the mounting of the process cartridge 2.

  Further, FIG. 5 shows a flow of a mounting confirmation process at the time of printing, which is a feature of the present invention. When printing is required in the image forming apparatus 1, the controller 23 determines the size of the recording paper S, the paper feed tray 18 to be used, whether the output image is color or monochrome, and any color toner for output. Is sent to the CPU 24 of the developing unit 4, and a print request including information such as the number of prints is transmitted.

  When the CPU 24 receives a print request, it first performs priority color determination processing for confirming the development color necessary for outputting the data requested for printing, and then mounting the process cartridge 2 of the development color necessary for output. Priority detection processing for confirming the presence or absence of toner is performed, and finally subordinate detection processing for confirming whether or not the process cartridge 2 having a development color other than the development color necessary for output is mounted is performed.

  FIG. 6 shows details of the priority color determination process. In this process, the CPU 24 confirms the information sent from the controller, confirms whether or not the image data includes Y color, and if Y data is included, the Y of the nonvolatile memory 26 is confirmed. Set the priority bit of the color cartridge. Similarly, data of M color, C color, and K color are confirmed in order, and if there is data of that color, the priority bit of the development color is set.

  FIG. 7 shows details of the priority detection process. In this process, first, a print permission setting for accepting a printing (image forming) operation is performed, and then priority bits are checked in the order of Y, M, C, and K, and the process cartridge 2 in which the priority bits are set. Perform priority check to confirm wearing. The CPU 24 prohibits printing if there is a development color in which the priority bit is set and the process cartridge 2 is not mounted, and all the process cartridges 2 in which the priority bit is set are mounted. If so, printing is started.

  As shown in FIG. 8, the priority of each development color is set as shown in FIG. 8. If the priority bit of the development color is set and the detection execution bit is not set, the detection execution bit is set and the process cartridge 2 is checked. Check for wearing. If the process cartridge 2 is not attached, the CPU 24 sets the development color non-attachment bit in the nonvolatile memory 26 and notifies the controller 23 that the development color process cartridge 2 is not attached.

  In this priority confirmation process, it is not confirmed whether or not the development color in which the priority bit is set or the development color process cartridge 2 in which the detection execution bit is already set in the normal attachment confirmation process. That is, this priority confirmation process is a process that is performed only when a print request is received after the detection execution bit is reset until the normal attachment confirmation process is completed.

  In the priority confirmation processing, only the mounting of the development color process cartridge 2 necessary for outputting the image data requested to be printed is preferentially confirmed, and if the development color process cartridge 2 necessary for output is available, Printing is started even if the installation of the process cartridge 2 is not confirmed.

  FIG. 9 shows details of the subordinate detection process. In this process, a subordinate confirmation process for confirming whether or not the development color process cartridge 2 is mounted in the normal mounting confirmation process and priority confirmation process is performed in the order of Y, M, C, and K. It is like that. That is, the process cartridge 2 that has already been checked for mounting is not checked for overlapping mounting.

  For example, when the cover of the image forming apparatus 1 is opened for jamming (paper jamming) and the cover is closed after the jammed recording paper S is removed, the above-described mounting confirmation processing is started. In the case of a conventional image forming apparatus, even if a print request is issued immediately after the cover is closed, the printing operation cannot be started until it is confirmed that all the development color process cartridges 2 are installed. However, when the image forming apparatus 1 of the present embodiment receives a print request, the image forming apparatus 1 determines the development color necessary for printing by the priority color determination process, and the process cartridge 2 of the development color necessary for printing by the priority detection process. If it can be confirmed that is attached, the printing operation is started without waiting for the subordinate detection process. If the development colors required for printing are only Y and M, if the mounting of the process cartridges 2 for Y and M can be confirmed in the priority detection process, the C and K colors in the subordinate detection process can be confirmed. The printing operation is started without waiting for confirmation of the mounting of the process cartridge 2.

  In the subordinate confirmation process, as shown in FIG. 10, for the process cartridge 2 in which the detection execution bit is not set, the detection execution bit is set and then the presence / absence of the mounting is checked. Then, the controller 23 is notified accordingly.

  Unlike the priority detection process, the result of the subordinate detection process is to check whether or not the process cartridge 2 having a development color unnecessary for printing is attached, and thus does not affect the availability of the printing operation.

  However, in preparation for the next print request, in each of the priority detection processing and the subordinate detection processing, for each process cartridge 2 that has been confirmed to be mounted, control of toner replenishment and control of development output potential adjustment is started each time. It is desirable to do.

  In the image forming apparatus 1, in the priority detection process, if the development color process cartridges 2 necessary for output are prepared, the printing operation is started without waiting for the inferiority detection process, so the waiting time until printing is short. The subordinate process is executed in parallel with the printing operation.

  FIG. 11 shows the configuration of the second embodiment of the present invention. The configuration of this embodiment is different from that of the first embodiment only in the connection method between the CPU 24 and the non-volatile memory 27 of the process cartridge 2 for each color, and thus a duplicate description is omitted.

  In the present embodiment, each nonvolatile memory 27 is connected to the CPU 24 via an independent communication line. As a result, the CPU 24 can communicate with the process cartridge 2 of any developing color by the address of the communication line without the confirmation procedure like the reset signal of the first embodiment.

  As shown in the present embodiment, the communication procedure between the CPU 24 and the process cartridge 2 and the means for the CPU 24 to confirm whether the process cartridge 2 is mounted are not limited in the present invention.

  12 and 13 show alternatives of the priority confirmation process and the subordinate confirmation process of the first embodiment. According to this alternative, every time the CPU 24 receives a print request, the CPU 24 checks whether or not all the process cartridges 2 are mounted in the priority confirmation process or the subordinate confirmation process.

1 is a schematic diagram of an image forming apparatus according to a first embodiment of the present invention. FIG. 2 is a main part configuration diagram relating to control of the image forming apparatus of FIG. 1. FIG. 3 is a waveform diagram of a reset signal transmitted by the CPU of FIG. 2. FIG. 3 is a flowchart of normal process cartridge mounting confirmation processing by the CPU of FIG. 2. FIG. 3 is a flowchart of process cartridge mounting confirmation processing during printing by the CPU of FIG. 2. FIG. 6 is a detailed flowchart of priority color determination processing in FIG. 5. 6 is a detailed flowchart of the priority detection process of FIG. FIG. 8 is a detailed flowchart of priority confirmation processing in FIG. 7. FIG. 6 is a detailed flowchart of the subordinate detection process of FIG. 5. The detailed flowchart of the subordinate confirmation process of FIG. FIG. 3 is a main part configuration diagram relating to control of the image forming apparatus according to the first embodiment of the present invention. FIG. 9 is a flowchart of alternative priority confirmation processing in FIG. 8. The flowchart of the subordinate confirmation process of the alternative of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Process cartridge 4 Developing unit 23 Controller 24 CPU
26 Nonvolatile memory 27 Nonvolatile memory

Claims (5)

In an image forming apparatus in which a plurality of process cartridges having different development colors are mounted and an image having a plurality of colors can be printed.
Check the development color required for the output of the image data that received the print request,
Check whether the process cartridge of the development color necessary for the output is installed,
An image forming apparatus characterized in that an image forming operation is started immediately when all the process cartridges of a developing color necessary for the output are mounted.   2. The plurality of process cartridges are all connected on the same communication line, and return a response signal to the communication line when receiving a color code indicating a development color of the process cartridge from the communication line. The image forming apparatus described in 1. When a predetermined condition is satisfied, check whether or not all the process cartridges are mounted in a predetermined order,
3. The image forming apparatus according to claim 1, wherein when the print request is received, the process cartridge that has already been checked for mounting is not checked for mounting again. 4.   4. The image forming apparatus according to claim 1, wherein toner supply control is started from the process cartridge that has been confirmed to be mounted.   5. The image forming apparatus according to claim 1, wherein development output potential adjustment control is started from the process cartridge that has been confirmed to be mounted.

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