JP4330358B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus including a page memory for inputting a read original image, a hard disk for holding the read original image, and a control unit for controlling both.
[0002]
[Prior art]
In an image forming system in which a plurality of image forming apparatuses are connected and operated, a technique for efficiently using memory resources is known (see, for example, Patent Document 1).
[Patent Document 1]
[Patent Document 1] Japanese Patent Laid-Open No. 2001-013827
[Problems to be solved by the invention]
In recent years, control using an RTOS (Real Time Operation System) is known for control of an image forming apparatus. By the way, in a tandem-type full-color image forming apparatus that has a page memory in units of A4 images and controls image input and image output in parallel using RTOS, secure page memory for image input at RTOS control timing. However, there is a possibility that the image output timing will be greatly delayed, resulting in a decrease in productivity. Conversely, only page memory for image output can be secured, and it is expected that the timing of image input will be delayed.
According to the present invention, image data stored in a hard disk (HDD) by a document reading unit is expanded to a page memory having a predetermined attribute, and the attribute can be changed depending on the state of each page memory. An object of the present invention is to provide an image forming apparatus capable of performing a reading operation and an image output operation in parallel to prevent a decrease in productivity.
[0004]
[Means for Solving the Problems]
To achieve the above object, an invention according to claim 1, and a hard disk for holding a plurality of page memory to input the document image read, the original image read, and control means for controlling both, more In the image forming apparatus including the plurality of developing devices, the control unit reads the number of page memories corresponding to the number of the plurality of developing devices out of the plurality of page memories from the hard disk when outputting an image. Assigned to each of the plurality of developing devices as output-dedicated page memories having output-dedicated attributes, and the read original image is input to a page memory other than the output-dedicated page memory, and the page memory When the output of the input original image is started after the original image is input, the allocation of the page memory dedicated for output is changed. And allocating a page memory for outputting the document image as the output-only page memory Te.
According to a second aspect of the present invention, in the first aspect, when the image data to be output does not exist in the page memory, the control means reads the image data to be output from the hard disk to the output dedicated page memory. When the read original image is input to a page memory other than the output-dedicated page memory while the image data to be output is read from the hard disk to the output-dedicated page memory, the image data is read from the hard disk. When the output of the input document image is completed after the output of the image data is completed, a page memory that changes the allocation of the output dedicated page memory and outputs the document image is used as the output dedicated page memory. It is characterized by assigning.
According to a third aspect of the present invention, in the first or second aspect, the number of page memories allocated as the output dedicated page memory is the same as the number of the developing devices.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a functional block diagram of a digital image forming apparatus according to an embodiment of the present invention.
The operation unit 100 includes a print start key, a numeric keypad for determining the number of copies, an apparatus function setting key for setting various functions of the digital image forming apparatus, a system function setting key for setting functions related to the image forming system, It has a liquid crystal touch panel that displays functions and data.
The ADF unit 200 feeds the set document to the contact glass at a predetermined timing, reads the document, and discharges the document at a predetermined timing. The scanner IPU unit 300 irradiates a document set on the contact glass with a lamp, forms an image of the reflected light on a CCD through a mirror group, a filter, and a lens, amplifies the photoelectrically converted signal, and performs A / D conversion. Get digital image data. The scanner IPU unit 300 includes image data patterned therein, and can output the internal pattern according to an instruction from the main controller 400.
The digital image data is subjected to processing such as predetermined shading correction and gamma correction. In addition, if there is a scaling process or a processing process designated by the operation unit 100 or the main controller 400, these processes are also performed, and the digital image data in the effective image area is sent to the main controller 400 at a predetermined timing. . The main controller 400 outputs the image data sent from the scanner IPU unit 300 to the page memory 500 and the HDD 600 and holds it. If there is a request for image output from the printer control unit 700, the image data requested from the page memory 500 is sent to the printer control unit 700.
The printer control unit 700 performs gamma conversion and the like on the digital image data sent from the main controller 400 to match the characteristics specific to the printer, and generates an electrostatic latent image based on this by driving the LD. It is formed on a photosensitive member charged by light irradiation. The electrostatic latent image is visualized with toner, transferred to a transfer material such as paper, melted and fixed by a fixing device, and the transfer material is discharged out of the digital image forming apparatus.
The sorter unit 800 sorts and discharges the discharged transfer material according to the mode set by the operation unit. The bank 900 accommodates various transfer materials.
[0006]
FIG. 2 is a diagram showing in detail the image forming system and printer control unit of the digital copying machine shown in FIG. The printer control unit 700 includes a system control unit 1, a development processing unit 2, four interface units 3-3k, 3-3m, 3-3c, and 3-3y connected to the two, and four image data writing devices. 3-4k, 3-4m, 3-4c, and 3-4y.
Each of the image data writing devices 3-4k, 3-4m, 3-4c, and 3-4y has a polygon mirror that scans laser light under the control of the system control unit 1 and a laser optical system, and is not shown in the lower part thereof. A laser light irradiation window is provided.
The image forming units M, C, Y, and K for the respective colors of the color image forming apparatus are arranged in this order in the paper transport direction. Since the image forming units M, C, Y, and K of the respective colors are identical in configuration, only the magenta image forming unit M will be described here.
The image forming unit M includes a drum-shaped photosensitive member 3-5, a charger 3-6, a developing device 3-7, a static elimination lamp 3-8, a transfer device 3-9, a static elimination device 3-10, and a cleaning device 3- 11. The photoconductor 3-5 can use a photoconductive photoconductor and a dielectric, and can also use an organic photoconductor and a dielectric according to the material of the carrier.
[0007]
The sheet conveying unit includes contact rollers 3-12 and 3-13, a charger 3-14, a transfer belt 3-15, a static eliminator 3-16, a roller unit 3-17, a belt cleaning 3-18, and a fixing device 3-19. It is composed of
The image data expanded by the expansion processing unit 2 is input to the image data writing device 3-4m via the interface unit 3-3m. The image data writing device 3-4m is driven by a signal from the system control unit 1, and the image forming unit M transfers the image data.
As shown in the figure, the photosensitive member 3-5 disposed below the image data writing device 3-4m is negatively charged by the disposed charger 3-6, and then the latent image is read by the image data writing device 3-4m. An image is formed. A developing unit 3-7 installed at a specific position around the photoreceptor 3-5 supplies toner to the photoreceptor 3-5 on which the latent image is formed, and the latent image formed on the photoreceptor 3-5 is Visualized as a toner image.
By irradiating the toner image visualized on the photosensitive member 3-5 with light from the neutralizing lamp 3-8, the adhesion force of the toner is weakened, and the transfer belt 3-15 is discharged by the transfer device 3-9. The toner image is transferred to the sheet 3-20 being conveyed. The toner remaining on the surface of the photoreceptor 3-5 after the toner image is transferred to the sheet 3-20 is removed by the charge eliminator 3-16 and removed by the cleaning device arranged in the half after the rotation of the photoreceptor 3-5. Is done. Then, uniform charging is newly performed by the charger 3-6 on the surface of the photoreceptor 3-5.
When the process of the image forming unit M is completed, the image forming unit C, the image forming unit Y, and the image forming unit K transfer the remaining colors in the same process as the image forming unit M, respectively.
In this way, the toner images of the respective colors are transferred to the paper 3-20 conveyed by the transfer belt 3-15, and a desired toner image is formed on the paper 3-20. Thereafter, the sheet 3-20 on which the toner image is formed is conveyed to a fixing device 3-19 having two rollers. The fixing device 3-19 fixes the toner image transferred to the paper 3-20 by melting the toner of the color image formed on the paper 3-20 with a desired heat and pressure, whereby the color image is applied to the paper. Printed.
[0008]
FIG. 3 is a diagram illustrating an example of a control command sequence among the scanner IPU unit, the printer control unit, and the main controller at the time of image input and image output, and FIG. 4 is a flowchart illustrating an example of a page memory acquisition process at the time of image input / output. .
Although the color mode, the paper, the scaling factor, the number of copies, and the like are set by the operation unit 100 and are not illustrated, when the start button is pressed, the operation unit 100 notifies the main controller 400 of the set various modes.
The main controller 400 issues a document (image) reading request command and an image printing request command to the scanner IPU unit 300 and the printer control unit 700 based on the set various modes and the number of copies.
When the scanner IPU unit 300 and the printer control unit 700 each complete processing for image printing such as predetermined shading correction and gamma correction, and image print preparation processing such as LD drive processing for creating an electrostatic latent image, the main unit The controller 400 is notified of an image input preparation request and an image output preparation request, and upon receiving this command, the main controller 400 searches the usable page memory 500 and if there is a page memory 500 corresponding to the above condition. The image input preparation OK is notified to the scanner IPU unit 300 (FIG. 4, S1, S2, S3).
[0009]
In response to the image output preparation request, if the requested image exists in the page memory 500 (if the image input has already started), the printer controller 700 is notified of the image output preparation OK (FIG. 4, FIG. 4). S4, S5). If the image requested to be output does not exist on the page memory 500 and exists in the storage area of the HDD 600, the image is read from the HDD 600 to the page memory 500.
When an image is read out to the page memory 500, a usable output-only page memory is searched first. If there is an output-only page memory that can be used, the image is read out to the page memory 500 (FIG. 4, S7, S8, S9).
If there is no usable output-only page, a usable non-output dedicated page memory is searched. If there is a usable non-output dedicated page memory, an image is read out to the page memory 500. When the image reading is completed, the printer controller 700 is notified of the image output OK (FIG. 4, S10, S11, S12).
If there is no usable output-only page memory or non-output-only page memory, the page memory acquisition process is interrupted until the page memory 500 becomes usable, for example, the page memory acquisition process is performed again upon reception of an image transfer end notification. I do.
If the requested image does not exist in the page memory 500 or the storage area of the HDD 600 (image input will be performed from now on), the image output preparation request processing is suspended until the image is input, and the image input The image output preparation OK is notified when is started.
[0010]
When the scanner IPU unit 300 is notified of the image input preparation OK, it irradiates a lamp on the document set on the contact glass, forms an image of the reflected light on the CCD through a mirror group, a filter, and a lens, and performs photoelectric conversion. The signal is amplified and A / D converted, the digital image data is transferred to the main controller 400, and an image transfer notification command is issued.
When the image output preparation OK is notified, the printer control unit 700 performs gamma conversion or the like for matching the digital image data sent from the main controller 400 with the characteristics specific to the printer, and the electrostatic latent image based on the gamma conversion. Are formed on the photosensitive member charged by driving the LD.
Then, this is visualized with toner, transferred to a sheet, melted and fixed by a fixing device, and the sheet is discharged out of the digital image forming apparatus. When the formation of the electrostatic latent image on the photoconductor is completed, an image output end command is issued.
[0011]
5 and 6 are diagrams showing how the output-only page memory attribute is changed every time an image is printed. The tandem full-color image forming apparatus to which the present invention is applied has 12 pages of the page memory 500 for each A4 image, and the page memory dedicated to output is 4 pages equal to the number of developing devices. P12 is assigned as an output-only page memory.
In this page memory 500, it is impossible to input a document image. Also, the image transfer speed from the page memory 500 to the HDD 600 and the image transfer speed from the HDD 600 to the page memory 500 are faster than the document reading speed, and the image transfer from the page memory 500 to the HDD 600 is the corresponding document reading operation. Is going to end.
The manner in which the output-only page memory attribute is changed will be described with reference to FIG. When reading of the original 1 is started by optical scanning of the scanner, input of the original read image (Y1, M1, C1, K1) to each of the page memories P1 to P4 is started. When the input of the document image to the page memory 500 is started, the image can be output to the printer control unit 700.
When an image output request for the document 1 is notified from the printer controller 700 after the image input is started, each color (Y1, M1, C1, K1) of the document 1 image exists on the page memories P1 to P4. 400 can output each color of P1 to P4.
When output is started by the printer control unit 700, the attributes of the page memories P1 to P12 are changed. At this time, P9 to P12 are dedicated for output, and this page memory 500 is not in use. Therefore, P1 to P4 are set as output dedicated page memories, and P9 to P12 are changed to non-output dedicated page memory attributes.
At this time, image input to P9 to P12 becomes possible. If an image input request for document 2 is notified during image reading (image input) of document 1, images P1 to P4 are being input (or being input / output), and pages P5 to P8 can be used. Therefore, the image input is permitted using P5 to P8.
Next, when an output request for each color of the document 2 image is notified, if output of each color of P1 to P4 is completed, an image output OK command for each color of P5 to P8 is notified to the printer control unit 700, and the document Output of two images is started.
Since P1 to P4 are completed and P5 to p8 are used as outputs, P1 to P4 are used as non-output dedicated page memories, and P5 to P8 are used as output dedicated pages. Is a page memory that can be input.
[0012]
Next, an example of image input and output of an input image by the scanner IPU unit 300 during image reading / output from the HDD 600 will be described with reference to FIG. Similarly to the above, it is assumed that 12 pages of the page memory 500 for each A4 image are provided, and the page memory dedicated to output is 4 pages equal to the number of developing devices, and P9 to P12 are assigned as output dedicated page memories in the initial state. .
When an image output (accumulated 1 image) request is notified from the printer control unit 700, if the output requested image does not exist in the page memory 500, the main controller 400 searches for the accumulated 1 image stored in the HDD 600. If there is one stored image in the HDD 600, the image data is read from the HDD 600 to pages P9 to P12 which are output-only pages, and the output preparation OK of the stored one image is notified.
When the image of the document 1 is input from the scanner IPU unit 300 in parallel, P1 to P4 that are unused are used and image input is started. When the output of the original 1 image is output and the output request of the original 1 image is notified, and when the printer control unit 700 is notified of the start of image output after output preparation is OK, the output dedicated pages P9 to P12 that read out the stored 1 image from the HDD 600 The memory attribute is changed to P1 to P4, and an image can be input to P9 to P12.
When the accumulated image is output (printed) continuously, the stored image is not read out only to the output dedicated page memory, and if there is a non-output dedicated page memory that is not in use (not in image input), The non-output-dedicated page memory is used to read the image stored in the HDD 600, and the output-dedicated page memory attribute is changed when image output is started.
FIG. 7 is a flowchart of the output-only page memory attribute process. If the page memory (nn) attribute in which the output image exists is already an output-only page memory, the process ends (S11).
When the page memory (nn) attribute in which the output image exists is a non-output dedicated page memory, the output dedicated page memory in the unused state is searched from all the page memories, and the corresponding output dedicated page memory (n) If it exists, the attributes of the page memory (nn) and page memory (n) are changed. If there is no output-only page memory in the unused state, the process is terminated without changing the attribute (S12, S13, S14).
In the above example, an example of the operation of inputting / outputting A4 images in the A4 unit page memory 500 is shown. However, when handling A3 images, at least output page memory: 8 pages, non-output dedicated page memory: 8 It needs to be a face.
[0013]
【The invention's effect】
As described above, according to the first aspect, by using the page memory as the output-dedicated page memory, it is possible to prevent a decrease in productivity of document reading and image output.
According to the second aspect, in addition to the effect of the first aspect, since the output dedicated page memories are provided for at least the number of the developing devices, parallel operation of document reading and image output is guaranteed.
According to the third aspect, in addition to the effect of the first aspect, since the read-only page memory from the hard disk can be dynamically allocated, the page memory can be used efficiently.
[Brief description of the drawings]
FIG. 1 is a functional block diagram of a digital image forming apparatus according to an embodiment of the present invention.
2 is a diagram showing in detail an image forming system and a printer control unit of the digital copying machine shown in FIG. 1;
FIG. 3 is a diagram illustrating an example of a control command sequence between a scanner IPU unit, a printer control unit, and a main controller during image input and image output.
FIG. 4 is a flowchart illustrating an example of a page memory acquisition process during image input / output.
FIG. 5 is a diagram illustrating a state in which an output-only page memory attribute is changed every time an image is printed.
FIG. 6 is a diagram illustrating a state in which an output-only page memory attribute is changed every time an image is printed.
FIG. 7 is a flowchart illustrating an example of output-only page memory attribute processing.
[Explanation of symbols]
100 Operation unit 300 Scanner IPU unit 400 Main controller (control means)
500 page memory 600 HDD (hard disk)
700 Printer control unit

Claims (3)

In an image forming apparatus comprising a plurality of page memories for inputting a read original image, a hard disk for holding the read original image, a control means for controlling both, and a plurality of developing devices .
The control means includes
Of the plurality of page memories, the plurality of page memories corresponding to the number of the plurality of developing devices are used as output dedicated page memories having an output dedicated attribute for reading an image from a hard disk when outputting an image. Corresponding to each developing device,
The read document image is input to a page memory other than the output-dedicated page memory,
A page memory that changes the assignment of the output-dedicated page memory and outputs the document image when the output of the input document image is started after the document image is input to the page memory. An image forming apparatus characterized by being assigned as The control means according to claim 1,
When the image data to be output does not exist in the page memory, the image data to be output is read from the hard disk to the output dedicated page memory,
When the read original image is input to a page memory other than the output-dedicated page memory while the image data to be output is read from the hard disk to the output-dedicated page memory, the image data is read from the hard disk When the output of the input document image is started after the output of the image data is completed, a page memory for changing the allocation of the output dedicated page memory and outputting the document image is allocated as the output dedicated page memory. An image forming apparatus. 3. The image forming apparatus according to claim 1, wherein the number of page memories allocated as the output-only page memory is the same as the number of the developing devices.

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