JP2005035133A - Color image formation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color image formation device which can improve the durability of machine parts inside the device, can reduce power consumption within the device and can improve the printing productivity by reducing the number of change-over times of a printing mode even when a plurality of printing jobs are carried out at the same time. <P>SOLUTION: The color image formation device is configured to carry out a printing operation with a transfer belt mechanism kept in an isolate state (black and white mode) at the time of a printing request of a first white and black original. In the device, at the time of a printing request of a next color original, the printing operation is carried out with the transfer belt mechanism kept in a contact state (color mode), and a mode change-over prohibition timer is started to bring a printing mode change-over prohibition state. At the time of a printing request of a next black and white original, the printing operation is carried out in a state while the transfer belt mechanism is held in the contact state although the printing object original is black and white. A contact separation/separation contact change-over control for the transfer belt mechanism is limited until the mode change-over prohibition timer is counted UP, and therefore the transfer belt mechanism is prevented from moving up and down frequently. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a color image forming apparatus that performs monochrome printing or color printing on a document to be printed using a color print engine, such as a color laser printer or a color copying machine.
[0002]
[Prior art]
Color image forming apparatuses such as general color laser printers and color copiers are color modes that perform color printing using four types of toners of C (cyan), M (magenta), Y (yellow), and K (black). And a black and white mode for performing black and white printing using only one type of K toner. By the way, in the printing method at the time of color mode printing, after simultaneously forming toner images of each color on four independent photoconductors, the toner images of each color are sequentially transferred onto one transfer sheet. There is a method. When monochrome printing is performed using the four-drum method, only a K toner image is formed on the K photoconductor, and is transferred to the transfer paper by the K transfer device. In this case, other colors (C, M, Y In many cases, the photosensitive member and the transfer unit are not operated. The transfer operation may be accompanied by a vertical drive mechanical operation of the transfer unit. However, such a vertical drive operation is not preferable in terms of durability of mechanical parts in addition to the time required for switching the mode. .
Techniques for this measure are disclosed in the following patent documents.
[Patent Document 1]
JP 2001-121788 A [Patent Document 2]
Japanese Patent Laid-Open No. 2001-301240
Japanese Patent Application Laid-Open No. 2004-133867 describes that in a color printing apparatus, when a print request that causes a mode switch between a monochrome print mode and a color print mode is generated from the outside, the number of machine operations is limited during execution of one print job. A method of restricting switching from the color printing mode to the monochrome printing mode is adopted. For example, when a mode change occurs from a black and white document to a color document during one print job, the mode can be switched from black and white printing to color printing. The color printing mode state is maintained until it is detected that the printing operation in the mode has been performed. In this case, an image is formed in the color print mode even for a black and white document.
Patent Document 2 seeks to optimize the total time required for completion of a print job by obtaining the sum of monochrome printing / color printing time and mode switching time of a print job to be printed.
[0004]
[Problems to be solved by the invention]
When the technique of Patent Document 1 is used, it is possible to limit the number of machine operations that occur during one print job. However, when print jobs are executed simultaneously from a plurality of host computers, It is possible that job printing operations are executed alternately. When the print mode of the print job is requested to be executed by the color printing apparatus so that color printing and monochrome printing are mixed, the total number of machine operations that occur during the completion of the print job cannot be reduced.
Further, when the technique of Patent Document 2 is used, in order to optimize the total time required to complete the print job, “what time is the next print request generated”, “what is the next print request generated? It is necessary to know in advance that it is the “mode”, and if an unexpected print operation interrupt occurs (such as a multi-function color image forming device), the expected optimization will not be performed. There is.
[0005]
In view of the above problems, the present invention improves the durability of mechanical components inside a color image forming apparatus by reducing the number of print mode switching even when a plurality of print jobs are simultaneously executed. An object of the present invention is to provide a color image forming apparatus capable of reducing power consumption in the apparatus and improving printing productivity.
[0006]
[Means for Solving the Problems]
According to a first aspect of the present invention, in a color image forming apparatus having a monochrome printing mode and a color printing mode, an image data generating unit that generates image data from a document to be printed, and a printing mode of the monochrome printing mode or the color printing mode are provided. A print mode holding unit for holding, a print mode switching unit for switching the print mode held by the print mode holding unit, and the image data generated by the image data generating unit are held by the print mode holding unit. An image forming unit that forms an image on a predetermined medium to be imaged in a printing mode that is set, and a time measuring unit that measures an elapsed time from the start of an image forming operation by the image forming unit for each printing mode; Based on the elapsed time measured by the time measuring means, a mark for restricting the printing mode switching by the printing mode switching means. A mode limiting means, by providing, to achieve the above object.
[0007]
According to a second aspect of the present invention, in the color image forming apparatus according to the first aspect, the printing mode restriction unit performs the printing until the elapsed time of the color printing mode measured by the time measuring unit reaches a predetermined time. The mode switching means prohibits switching of the print mode from the color print mode to the monochrome print mode.
[0008]
According to a third aspect of the present invention, in the color image forming apparatus according to the second aspect, the printing mode restriction unit is configured such that when the elapsed time of the color printing mode measured by the time measuring unit reaches a predetermined time, The printing mode switching means permits switching of the printing mode from the color printing mode to the monochrome printing mode.
[0009]
According to a fourth aspect of the present invention, in the color image forming apparatus according to the first, second, or third aspect, a non-printing time for measuring an elapsed time after the image forming operation is completed by the image forming unit. The printing mode switching means further switches the printing mode to the monochrome printing mode which is the initial state when the non-printing elapsed time measured by the non-printing time measuring means reaches a predetermined time. It is characterized by.
[0010]
According to a fifth aspect of the present invention, in the color image forming apparatus according to the first, second, or third aspect, a non-printing time for measuring an elapsed time after the image forming operation is completed by the image forming unit. The printing mode restriction unit further includes a measuring unit, and the printing mode restriction unit changes from the color printing mode to the monochrome printing mode by the printing mode switching unit when the non-printing elapsed time measured by the non-printing time measuring unit reaches a predetermined time. It is characterized in that switching of the print mode to is permitted.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 5.
FIG. 1 is a block diagram illustrating a configuration example of a color image forming system having a color image forming apparatus according to the present embodiment. The color image forming apparatus according to the present embodiment is applied to a color printer.
This color image forming system is connected to the host computer 100A and the host computer 100B via a host computer 100A, a host computer 100B, a general-purpose I / F cable such as Centronics, USB, a network 300 such as TCP / IP, and the network 300. The color image forming apparatus 200 is configured.
[0012]
A printer driver 101 corresponding to the color image forming apparatus 200 is installed in each of the host computer 100A and the host computer 100B. Documents created by the host computer 100A and the host computer 100B are sent to the color image forming apparatus 200. Printed. The color image forming apparatus 200 includes a controller 201, a printer engine controller 202, and a printer engine 203. The controller 201 receives the command converted into the print language by the printer driver 101, converts it into a bitmap image in units of files or pages, and passes it to the printer engine controller 202. The printer engine controller 202 controls the data at a predetermined timing in consideration of the electrophotographic process, paper conveyance, and the like, and the printer engine 203 creates a latent image to be printed on the photosensitive member and attaches toner. , Transfer and fix on paper, and print work.
[0013]
FIG. 2 is a diagram illustrating an example of the print property screen of the printer driver 101. The print property screen can be started from the host computer 100A and the host computer 100B in FIG. 1, and each item on the print property screen can be set from each host computer. The print property screen has color / black and white selection items, and you can select either “color” or “black and white” as the print mode for the document to be printed. The image data for the document to be printed is selected. Is converted into a predetermined print language according to the print mode.
[0014]
Here, the “contact / separation / separation switching” control of the transport belt mechanism, which is performed when the printer engine 203 of FIG. 1 performs color printing / monochrome printing, will be described. When the “color” mode is selected in the printer driver 101, it is necessary to transfer four types of toners of C (cyan), M (magenta), Y (yellow), and K (black) to the paper. When the transport belt mechanism is raised (contacted) to the image forming unit corresponding to the C, M, Y, and K types, and the “monochrome” mode is selected by the printer driver 101, one type of K (black) is selected. Since it is necessary to transfer only the toner to the paper, the conveying belt mechanism is lowered (separated) from the image forming units corresponding to the three types of C, M, and Y.
That is, switching from the “color” mode to the “black and white” mode involves an operation of partially separating the transport belt mechanism from the image forming unit. This is called “switching”, and both are collectively referred to as “switching / separating / separating”.
[0015]
By the way, the host computer 100A and the host computer 100B in FIG. 1 can issue an independent print job execution request to the color image forming apparatus 200 via the network 300. For example, when the host computer 100A requests the color image forming apparatus 200 to execute a print job in the “black and white” mode and the host computer 100B simultaneously execute the print job in the “color” mode, the color image formation is performed depending on the timing. There may be a case where the apparatus 200 performs color printing and black-and-white printing alternately.
[0016]
Here, FIG. 3 shows a state of print mode switching when the color image forming apparatus according to the first embodiment alternately executes color printing and monochrome printing.
Referring to FIG. 3, when the color image forming apparatus according to the first embodiment is in the standby state ((1) Wait), the transport belt mechanism is in the initial state of “separation”. In this state, when the host computer 100A requests printing of a monochrome document, the color image forming apparatus executes a printing operation in the monochrome mode while keeping the conveyance belt mechanism in the “separated” state ((2) B / W ).
Thereafter, when a print request for a color original is made from the other host computer 100B before the next black and white print request is received from the host computer 100A, the color image forming apparatus changes the conveyance belt mechanism to the “contact” state, That is, the printing operation is executed in the color mode ((3) F / C). At the same time, the mode switching prohibition timer starts to enter a print mode switching prohibition state. Thereafter, when the host computer 100A makes a print request for the black and white original again, the print request is an execution request during the mode switching prohibition period. Is in the “contact” state, that is, the printing operation is executed in the color mode ((4) B / W).
[0017]
Thereafter, when the host computer 100B continuously issues a print request for a color document, the color image forming apparatus continuously executes the printing operation in the color mode while keeping the conveyance belt mechanism in the “contact” state (ie, in the color mode). (5) F / C, (6) F / C). Here, each color mode printing start is used as a trigger to restart the mode switching prohibition timer each time.
After the print request from the host computer 100A and the host computer 100B is temporarily interrupted ((7) Wait), when the print request for the black and white original is made from the host computer 100A, the print request is counted by the mode switching prohibition timer. Since this is an execution request during the mode switching prohibition period before UP, the color image forming apparatus executes the printing operation in the color mode while the document to be printed is black and white but the conveyance belt mechanism is in the “contact” state. ((8) B / W). While the monochrome document is being printed, the mode switching prohibition state is canceled by counting up the mode switching prohibition timer. For this reason, when a monochrome document print request is made next, the color image forming apparatus shifts the conveyance belt mechanism to the “separated” state, that is, executes a printing operation in the monochrome mode ((9) B / W).
Here, the count-up timing of the mode switching prohibition timer will be described. Count-up of the mode switching prohibition timer is performed at a timing when a predetermined time has elapsed after the mode switching prohibition timer is started.
[0018]
As described above, when a plurality of print jobs with different modes are requested from the host computer, the color image forming apparatus alternately executes color printing and monochrome printing, or the printing operation is interrupted between printings. There is a case. In both cases, since the color image forming apparatus restricts the “contact / separation / separation switching” control of the conveyor belt mechanism until the mode switching prohibition timer is counted up, the conveyor belt mechanism is frequently used. There is no such thing as going up and down.
[0019]
Next, FIG. 4 shows a state of print mode switching when the color image forming apparatus according to the second embodiment does not execute printing (non-printing period).
Referring to FIG. 4, the color image forming apparatus according to the second embodiment starts a non-printing period timer when the printer engine 203 of FIG. 1 enters a non-printing state, and the non-printing period timer is set to a predetermined value. The conveyance belt mechanism is initialized (transition to the “separation” state) triggered by the detection of the passage of time (timer count UP). This initialization process is executed even if the mode switching prohibition timer described in the first embodiment is before counting up.
As described above, when the state in which the printing operation is not performed for a certain period of time continues, the conveyance belt mechanism inside the color image forming apparatus automatically shifts to the lower position (initial position) to control this mechanism. In addition to reducing the load on electromagnetic components such as motors and clutches, the power consumed by the image forming apparatus can be reduced.
[0020]
Next, FIG. 5 shows how printing modes are switched when the color image forming apparatus according to the third embodiment does not execute printing (non-printing period).
Referring to FIG. 5, the color image forming apparatus according to the third embodiment starts a non-printing period timer when the printer engine 203 of FIG. 1 enters a non-printing state, as in the second embodiment. The mode switching prohibition timer described in the first embodiment is initialized (timer stop), triggered by the non-printing period timer detecting that the predetermined time has elapsed (timer count UP), and the “contact” of the conveyor belt mechanism is initiated. Allow state transition from to “separated”. Thereafter, when a black and white original is requested to be printed, the color image forming apparatus immediately shifts the conveying belt mechanism to the lower position (“separated” state) at that time, and executes the printing operation in the black and white mode.
As described above, when the state where the printing operation is not performed for a certain period of time is continued, the conveyance belt mechanism inside the color image forming apparatus is moved from the upper position (the “contact” state) to the lower position (the “separation” state). ) Is permitted, and a monochrome document can be immediately printed in the monochrome mode.
[0021]
【The invention's effect】
According to the color image forming apparatus of claim 1, the period for prohibiting switching from the print mode when the image forming operation is started first to the different print mode is defined, and image formation is performed in the different print mode during the period. In the case of performing image formation, image formation is performed in the print mode when the image formation operation is executed first. Therefore, when a plurality of print jobs are requested to be executed, the print mode is not frequently switched, and as a result, the machine life of the color image forming apparatus can be improved and the print productivity can be improved. .
[0022]
According to the color image forming apparatus of the second aspect, the period for prohibiting switching from the color printing mode to the black and white printing mode is defined, and when a black and white document print request is made during the period, the color printing mode is set. Image formation is performed. Therefore, when a plurality of print jobs are requested to be executed, the print mode is not frequently switched, and as a result, the machine life of the color image forming apparatus can be improved and the print productivity can be improved. .
[0023]
According to the color image forming apparatus of the third aspect, the period for prohibiting switching from the color printing mode to the black and white printing mode is defined, and when a black and white document print request is made during the period, the color printing mode is set. Image formation is performed, and when a black and white document print request is made after the end of the period, the image formation is performed in the monochrome print mode. Therefore, when a plurality of print jobs are requested to be executed, the print mode is not frequently switched, and as a result, the machine life of the color image forming apparatus can be improved and the print productivity can be improved. .
[0024]
According to the color image forming apparatus of the fourth aspect, when the state in which the printing operation is not performed for a predetermined time after the completion of the printing operation is continued, the conveyance belt mechanism in the color image forming apparatus is in the initial state (“separated” state). Therefore, it is possible to immediately form an image in an appropriate print mode (execute a monochrome print job in the monochrome print mode), and to reduce power consumption in the color image forming apparatus.
[0025]
According to the color image forming apparatus of claim 5, when the state in which the printing operation is not performed for a predetermined time after the printing operation is completed continues, it is prohibited to switch from the specified color printing mode to the monochrome printing mode. Even so, by allowing the transfer belt mechanism inside the color image forming apparatus to transition from the upper position (“contact” state) to the lower position (“separation” state), it is possible to immediately perform an appropriate print mode. Image formation can be performed (a monochrome print job is executed in the monochrome print mode), and power consumption in the color image forming apparatus can be reduced.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration example of a color image forming system having a color image forming apparatus according to an embodiment.
FIG. 2 is a diagram illustrating an example of a print property screen of a printer driver.
FIG. 3 is a diagram illustrating how printing modes are switched when the color image forming apparatus according to the first embodiment alternately executes color printing and monochrome printing.
FIG. 4 is a diagram illustrating a state of print mode switching when the color image forming apparatus according to the second embodiment does not execute printing (non-printing period).
FIG. 5 is a diagram illustrating a state of print mode switching when the color image forming apparatus according to the third embodiment does not execute printing (non-printing period).
[Explanation of symbols]
100A host computer 100B host computer 101 printer driver 200 color image forming apparatus 201 controller 202 printer engine controller 203 printer engine 300 network

Claims (5)

In a color image forming apparatus having a monochrome printing mode and a color printing mode,
Image data generating means for generating image data from a document to be printed;
A print mode holding means for holding a black and white print mode or a color print mode;
Print mode switching means for switching the print mode held by the print mode holding means;
Image forming means for forming an image on the predetermined medium to be image formed in the print mode held by the print mode holding means, the image data generated by the image data generating means;
A time measuring unit that measures an elapsed time from the start of the image forming operation by the image forming unit for each printing mode;
A color image forming apparatus comprising: a print mode restriction unit that restricts switching of a print mode by the print mode switching unit based on an elapsed time measured by the time measurement unit. The printing mode restriction unit prohibits switching of the printing mode from the color printing mode to the monochrome printing mode by the printing mode switching unit until the elapsed time of the color printing mode measured by the time measuring unit reaches a predetermined time. The color image forming apparatus according to claim 1, wherein: The printing mode restriction unit switches the printing mode from the color printing mode to the monochrome printing mode by the printing mode switching unit when the elapsed time of the color printing mode measured by the time measuring unit reaches a predetermined time. The color image forming apparatus according to claim 2, wherein: A non-printing time measuring unit that measures an elapsed time after the image forming operation is completed in the image forming unit;
The printing mode switching unit switches the printing mode to a monochrome printing mode which is an initial state when the non-printing elapsed time measured by the non-printing time measuring unit reaches a predetermined time. The color image forming apparatus according to claim 1, 2 or 3. A non-printing time measuring unit that measures an elapsed time after the image forming operation is completed in the image forming unit;
The printing mode restriction unit switches the printing mode from the color printing mode to the monochrome printing mode by the printing mode switching unit when the non-printing elapsed time measured by the non-printing time measuring unit reaches a predetermined time. The color image forming apparatus according to claim 1, wherein the color image forming apparatus is permitted.

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