JP2002229392A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device capable of preventing a printing error by performing warning display when printing is impossible. SOLUTION: This image forming device performing the copying operation of an original or the printing operation of an image is provided with an image area detection means for detecting an image area by reading the original or detecting the image area from inputted printing data, a printing area setting means for setting a printing area for outputted paper, a detection means (area decision part) 48 for detecting the presence/absence of the image area on the outside of the printing area, and a warning display means for performing the warning display that the printing is impossible when the image area is detected on the outside of the printing area. At the time of copying or printing, whether or not the image data exists on the outside of the printing area is judged according to the image area and the printing area of the outputted paper. In the case of detecting it, the warning display that printing is impossible is performed, whereby the printing error is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image forming apparatus for reproducing image information by copying or printing.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus for reproducing image information by copying or printing, it is determined whether or not printing has ended by comparing the size of a document with the size of an output sheet. If image scaling is set, the size of the document is scaled by performing scaling processing, and then the size of the printout is compared with the output paper size.

[0003]

However, in the above-described conventional print out determination method, only the size of the original and the size of the output paper are simply compared, and the extent to which the image area is included in the original is determined. Furthermore, no determination has been made including how far the printable area of the output paper is. For this reason, there is no problem in the determination of the print out, and the print out may be confirmed only after looking at the print result. When such print breaks occur, it is necessary to change the magnification of the image or change the output paper and print again. In particular, in color printing, the printing cost is high, and such printing errors should be prevented as much as possible.

On the other hand, Japanese Patent Application Laid-Open No. H11-263519 discloses a method of displaying a warning when an image area and a binding area of an output sheet overlap. However, this method is intended to prevent overlapping of images at the binding margin, and is not intended to prevent print out on output paper.

SUMMARY OF THE INVENTION The present invention has been made to solve such problems of the prior art, and it is an object of the present invention to provide an image forming apparatus capable of displaying a warning when a print out occurs and preventing a printing error. I do.

[0006]

According to an image forming apparatus of the present invention, in an image forming apparatus for performing a copying operation of an original or an image printing operation, an original is read to detect an image area, or an image area is detected from input print data. Image area detecting means for detecting an image area, printing area setting means for setting a printing area on output paper, detecting means for detecting the presence or absence of an image area outside the printing area, and detecting an image area outside the printing area A warning display unit for displaying a warning of occurrence of print out at times, thereby achieving the above object.

[0007] According to the above configuration, at the time of copying or printing, it is detected whether or not there is image data outside the printing area based on the image area and the printing area of the output paper. , It is possible to prevent printing errors.

The means for detecting the presence / absence of an image area outside the print area includes the presence / absence of an image area outside the print area based on image data flowing at the time of document scanning by the scanner unit or image data flowing at the time of print data input. May be detected.

According to the above configuration, the presence or absence of image data outside the print area can be detected in real time.

The means for detecting the presence / absence of an image area outside the print area includes the presence / absence of an image area outside the print area based on the image data once stored in the memory when the original is scanned, or the image data once stored in the memory when the print data is input. May be detected.

According to the above configuration, once image data is temporarily stored in the memory, the presence / absence of image data only outside the print area is detected, so that the presence / absence of image data outside the print area can be detected in a short time. Become.

The means for detecting the presence or absence of an image area outside the printing area determines that the image data occupies an image when the area occupied by the image data is larger than a predetermined reference. It may be determined as garbage.

According to the above configuration, when detecting the presence or absence of image data outside the print area, it is possible to prevent erroneous detection by determining dirt or dust other than data.

The image area detecting means may detect the image area based on the image data after the magnification processing when the magnification of the image is set.

According to the above arrangement, when image scaling is set, image data outside the printing area is determined by the final data (printing area and image area) subjected to scaling processing. False detection can be prevented.

The image area detecting means may detect the image area based on the image data after the rotation processing when the rotation of the image is set.

According to the above configuration, when image rotation is set, erroneous detection can be prevented by judging image data outside the print area with the final data subjected to the rotation processing. .

The image area detecting means may detect the image area based on the image data after the shift processing for the binding margin when the binding margin of the sheet is set.

According to the above configuration, when a binding margin for a sheet is set, erroneous detection can be prevented by determining the image data outside the printing area with the final data subjected to the binding margin processing. Becomes

In the case where the one-set two-copy mode is set in the image area detecting means. The image area is detected based on the image data after one set and two copy processes, and the printing area setting means detects the image area. When the 1 set 2 copy mode is set. A print area for one set and two copies may be set.

According to the above arrangement, when the one-set two-copy mode is set, erroneous detection is prevented by determining the image data outside the print area by the final data subjected to the one-set two-copy processing. It becomes possible.

[0022]

FIG. 1 is a schematic front sectional view showing the structure of a digital color copying machine 1 which is an embodiment of the image forming apparatus of the present invention. A document table 111 and an operation panel are provided on the upper surface of the copying machine main body 1, and an image reading unit 110 and an image forming unit 210 are provided inside the copying machine main body 1.

On the upper surface of the document table 111, a double-sided automatic document feeder (RADF: Recirculating Au) is provided.
tomatic Document Feeder) 1
Reference numeral 12 is supported on the document table 111 so as to be openable and closable, and is mounted with a predetermined positional relationship. The automatic two-sided automatic document feeder 112 first sets the image reading unit 11 so that one side of the original is at a predetermined position on the original platen 111.
The document is conveyed so as to face the original document 0, and after image reading on one side is completed, the document is turned over so that the other side of the document faces the image reading unit 110 at a predetermined position on the document table 111. And is conveyed toward the document table 111. After the two-sided automatic document feeder 112 finishes reading both sides of an original, the original is ejected and a double-sided conveyance operation is performed for the next original. The operations of conveying the document and inverting the original as described above are controlled in relation to the operation of the entire copying machine.

The image reading section 110 is arranged below the document table 111 for reading an image of the document conveyed onto the document table 111 by the automatic duplex document feeder 112. The image reading unit 110 has document scanning bodies 113 and 114 that can reciprocate in parallel along the lower surface of the document table 111, an optical lens 115, and a CCD line sensor 116 that is a photoelectric conversion element.

The document scanning bodies 113 and 114 are composed of a first scanning unit 113 and a second scanning unit 114. The first scanning unit 113 has an exposure lamp for exposing the surface of the original image, and a first mirror for deflecting the reflected light image from the original in a predetermined direction. Are reciprocated in parallel at a predetermined scanning speed while maintaining the above distance. The second scanning unit 114 has a second mirror and a third mirror that further deflect the reflected light image from the document deflected by the first mirror of the first scanning unit 113 in a predetermined direction, It reciprocates in parallel with the first scanning unit 113 while maintaining a constant speed relationship.

The optical lens 115 reduces the reflected light image from the document deflected by the third mirror of the second scanning unit, and forms the reduced light image at a writing position on the CCD line sensor 116. Things.

The CCD line sensor 116 sequentially converts the formed light images into photoelectric signals and outputs them as electric signals. The CCD line sensor 116 is a three-line color CCD capable of reading a black-and-white image or a color image and outputting line data separated into R (red), G (green), and B (blue) color components. . The document image information converted into an electric signal by the CCD line sensor 116 is further transferred to an image processing unit (not shown) and subjected to predetermined image data processing.

Next, the configuration of the image forming section 210 and the configuration of each section related to the image forming section 210 will be described. Below the image forming unit 210, there is provided a paper feed mechanism 211 that separates sheets (recording media) P stacked and accommodated in a sheet tray one by one and supplies the separated sheets to the image forming unit 210. Then, the sheets P separated and supplied one by one are conveyed to the image forming unit 210 at a controlled timing by a pair of registration rollers 212 disposed in front of the image forming unit 210. Further, the sheet P on which an image is formed on one side is again conveyed and supplied to the image forming unit 210 in synchronization with the image formation of the image forming unit 210.

Further, below the image forming section 210, a transfer and transport belt mechanism 213 is disposed. The transfer conveyance belt mechanism 213 includes a driving roller 214 and a driven roller 215.
The paper P is electrostatically attracted to a transfer / transport belt 216 stretched so as to extend substantially in parallel with the sheet P, and is transported.

Further, a fixing device 217 for fixing the toner image transferred and formed on the sheet P on the sheet P is provided downstream of the transfer and conveyance belt mechanism 213 in the sheet conveyance path.
Is arranged. The paper P that has passed through the nip between the pair of fixing rollers provided in the fixing device 217 is
After the transfer direction switching gate 218, the discharge roller 21
9, the paper is discharged onto a paper discharge tray 220 attached to the outer wall of the copying machine body 1.

The switching gate 218 provides a path for conveying the sheet P after the toner image is fixed between a path for discharging the sheet P to the copying machine main body 1 and a path for re-supplying the sheet P to the image forming section 210. Is used to selectively switch over. The image forming unit 210 is again operated by the switching gate 218.
The paper P whose transport direction has been switched toward is turned over via the switchback transport path 221 and then supplied again to the image forming unit 210.

Above the transfer belt 216 in the image forming section 210, a first image forming station Pa, a second image forming station Pb, and a third image forming station are disposed adjacent to the transfer belt 216. Pc
And a fourth image forming station Pd are arranged in order from the upstream side of the sheet transport path.

The transfer conveyance belt 216 is driven by the driving roller 21.
4, the paper P is frictionally driven in the direction indicated by the arrow Z in FIG. 1, grips the paper P supplied and transported through the paper feeding mechanism 211 as described above, and transports the paper P sequentially to the image forming stations Pa to Pd.

Each of the image stations Pa to Pd has substantially the same configuration. Each image station Pa,
Pb, Pc and Pd are photosensitive drums 222a, 222b and 222c which are driven to rotate in the direction of arrow F shown in FIG.
And 222d. Each photosensitive drum 22
2a to 222d, the photosensitive drums 222a to 222d
Chargers 223a and 223 for uniformly charging 22d respectively
b, 223c and 223d, and the photosensitive drums 222a to 222a-2
Developing devices 224a, 224b, 224c and 224d for developing the electrostatic latent images formed on 22d, and transfer devices 25a and 225b for transferring the developed toner images on the photosensitive drums 222a to 222d to the paper P , 225c, 2
25d and cleaning devices 226a and 226 for removing toner remaining on the photosensitive drums 222a to 222d.
b, 226c, and 226d correspond to the photosensitive drums 222a to 222d.
They are sequentially arranged along the rotation direction of 222d.

Each of the photosensitive drums 222a to 222d
Above the laser beam scanner unit 227a,
227b, 227c and 227d are provided respectively.
The laser beam scanner units 227a to 227d are
Polygon mirror (deflection device) 240 for deflecting dot light modulated in accordance with image data in the main scanning direction
f, 241a, 241b, 241c, and 241d for forming laser beams deflected by the polygon mirrors 240a to 240d on the surfaces of the photosensitive drums 222a to 222d.
And mirrors 242a, 242b, 242c, 242d, 2
43a, 243b, 243c, 243d and the like.

A pixel signal corresponding to a black component image of a color original image is supplied to the laser beam scanner unit 227a.
The laser beam scanner unit 227b receives a pixel signal corresponding to the cyan color component image of the color document image, the laser beam scanner unit 227c receives a pixel signal corresponding to the magenta color component image of the color document image, and the laser beam scanner unit 227d. , A pixel signal corresponding to a yellow component image of a color original image is input.

As a result, the electrostatic images corresponding to the color-converted original image information are stored in the photosensitive drums 222a to 222d.
Formed on top. Then, black toner is applied to the developing device 227a, cyan toner is applied to the developing device 227b,
The developing device 227c contains magenta toner and the developing device 227d contains yellow toner. The electrostatic latent images on the photosensitive drums 222a to 222d are
The image is developed with the toner of each color. As a result, the document image information color-converted by the image forming unit 210 is reproduced as a toner image of each color.

Further, between the first image forming station Pa and the paper feed mechanism 211, a paper suction (brush) charger 228 is provided. This adsorption charger 228 includes
The surface of the transfer conveyance belt 216 is charged, and the paper feeding mechanism 21 is charged.
In the state where the sheet P supplied from the first image forming station P
The sheet is conveyed from a to the fourth image forming station Pd without shifting. On the other hand, between the fourth image forming station Pd and the fixing device 217,
4, a static eliminator 229 is provided almost directly above. An alternating current is applied to the neutralizer 229 to separate the paper P electrostatically attracted to the transport belt 216 from the transfer transport belt 216.

In the digital color copying machine having the above configuration, cut sheet-shaped paper is used as the paper P. The sheet P is sent out from the sheet cassette and fed to the sheet feeding mechanism 2.
When the paper P is fed into the guide of the paper feed conveyance path 11, the leading end of the paper P is detected by a sensor (not shown),
It is temporarily stopped by the pair of registration rollers 212 based on a detection signal output from this sensor. And
The sheet P is sent onto the transfer / conveying belt 216 rotating in the direction of arrow Z in FIG. 1 at the timing of each of the image stations Pa to Pd. At this time, the transfer conveyance belt 216
As described above, since the predetermined charging is performed on the attraction charger 228, the paper P is stably conveyed and supplied while passing through the image stations Pa to Pd.

In each of the image stations Pa to Pd, a toner image of each color is formed,
The paper P is superposed on the support surface of the paper P which is electrostatically attracted and conveyed by 16. When the transfer of the image by the fourth image forming station Pd is completed, the sheet P is sequentially separated from the transfer / conveying belt 216 by the neutralizer 229 from the leading end thereof, and is guided to the fixing device 217. Finally, the paper P on which the toner image has been fixed is discharged into a paper discharge port (not shown).
Is discharged onto the discharge tray 220 from the paper tray.

In the above description, the laser beam is scanned and exposed by the laser beam scanner units 227a to 227d to write light on the photosensitive member. However, a writing optical system (LED head) including a light emitting diode array and an imaging lens array may be used instead of the laser beam scanner unit. The LED head is smaller in size than the laser beam scanner unit, and has no moving parts, so it is silent. Therefore, it can be suitably used in an image forming apparatus such as a tandem type digital color copying machine which requires a plurality of optical writing units.

Next, the configuration and functions of the image processing section for color image information installed in the color digital copying machine will be described. FIG. 2 is a block diagram illustrating a configuration of an image processing unit included in the color digital copying machine. Although not shown in FIG. 1, the image processing unit processes data of the CCD line sensor 116 and outputs the processed data to the laser beam scanner units 227a to 227d.

The image processing section includes a document reading section (image data input section) 40, an image processing section 41, an image memory 43 including a hard disk device or a RAM (random access memory), an image data output section 42, It comprises a processing unit (CPU) 44, an image editing unit 45, and external interface units 46 and 47.

The document reading section 40 reads a black and white document or a color document image and outputs color data separated into RGB color components. The color CCD 40a has three lines, and the line data read by the color CCD 40a. A shading correction circuit 40b for correcting the line image level, a line matching unit 40c such as a line buffer for correcting a shift of image line data read by the three-line color CCD 40a, and lines of each color output from the three-line color CCD 40a. A sensor color correction unit 40d that corrects the color data of the data, an MTF correction unit 40e that corrects the change in the signal of each pixel so as to have a sharp edge, and a γ that corrects the brightness of the image to correct the visibility.
It comprises a correction unit 40f and the like.

The image processing section 41 includes a monochrome data generating section 41a for generating monochrome data (black and white original) from RGB signals, which are color image signals input from the original reading section 40, and outputs the RGB signals to each recording device of the printing apparatus. An input processing unit 41b for converting the input image data into a YMC signal and a clock conversion; and an area separating unit for separating whether the input image data is a character portion, a halftone photograph, or a photographic paper photograph. 41c, YMC output from the input processing unit 41a
A black generating unit 41d that performs under color removal processing based on a signal to generate black, a color correction circuit 41e that adjusts each color of a color image signal based on each color conversion table, and an image that is input based on a set magnification It comprises a zoom processing circuit 41f for converting the magnification of information, a spatial filter 41g, and a halftone processing section 41h for expressing gradation such as multi-level error diffusion and multi-level dither.

The halftone processed color image data is temporarily stored in the image memory 43. The image memory 43 stores 8 bits and 4 colors (32 bits) serially output from the image processing unit 41.
4) hard disks (rotary storage media) that sequentially receive image data of each bit, temporarily store the data in a buffer, convert 32-bit data into 8-bit 4-color image data, and store and manage the image data for each color. ) 43a,
43b, 43c and 43d. Further, since the positions of the respective image stations are different, the respective color image disks are temporarily stored in the delay buffer memory 43e (semiconductor memory) of the image memory 43, and the respective images are shifted in time to transmit image data to the respective laser scanner units. To prevent color misregistration.

The image data output unit 42 is provided with the halftone processing unit 4
1h, a laser control unit 42a that performs pulse width modulation based on each color image data, and a laser scanner unit of each color that performs laser recording based on a pulse width modulation signal corresponding to an image signal of each color output from the laser control unit 42a 42b, 42c, 42d, 4
2e.

The central processing unit (CPU) 44 arranges the original reading section 40, the image processing section 41, the image memory 43, the image data output section 42, the image editing section 45, which will be described later, and the external interfaces 46 and 47 in a predetermined sequence. Control based on

The image editing unit 45 includes a document reading unit 40,
An image processing unit 41 or an interface 46 described later;
This is for performing a predetermined image editing on the image data once stored in the image memory 43 via 47. In the image editing unit 45, editing work of image data is performed using the image memory 43e.

The interface 46 is a communication interface (here, wireless) for receiving image data from an external image input processing device (communication portable terminal, digital camera, digital video camera, etc.) provided separately from the digital copying machine 1. IR (infrared) communication which is a type of communication). The image data input from the interface 46 is also temporarily stored in the image processing unit 4.
1 to perform color space correction and the like, thereby converting the data level to a data level that can be handled by the image forming unit 210 of the digital copying machine 1 and storing and managing the data level in the hard disks 43b, 43c, 43d, and 43e of the image memory 43. Will be.

The interface 47 is a printer interface for inputting image data created by a personal computer.
X is a monochrome or color FAX interface for accepting received image data. The image data input from the interface 47 is a CMYK signal, which is once processed by the halftone processing unit 41h to be processed in the hard disks 43b, 43c, 43d, and 4d of the image memory 43.
3e is stored and managed.

Next, control of the entire digital copying machine will be described. FIG. 3 is a diagram for explaining a state in which the operation of each unit of the entire digital copying machine 1 is managed by a central processing unit (CPU) 44. An image data input unit (described as a document reading unit in FIG. 2) 40, an image processing unit 41, an image memory 43, and an image data output unit 42
The details of the central processing unit 44 are the same as those described with reference to FIG. 2, and will not be described here.

The central processing unit 44 also includes a RAD
Each drive mechanism constituting the digital copier 1 such as a scanner F, a scanner, and a laser printer is managed by sequence control, and outputs a control signal to each section. Further, an operation board unit 50 including an operation panel is connected to the central processing unit 44 so as to be able to communicate with each other, and a control signal indicating the copy mode content set and input by the operator in accordance with the operation of the operation panel. The digital color copier 1 is transferred to the central processing unit 44 and controlled so that the entire digital color copying machine 1 operates according to the set mode. Further, the central processing unit 44 transfers control signals indicating various operation states of the digital color copying machine 1 to the operation board unit 50, and the operation board unit 50 uses the control signals to determine what state the apparatus is currently in. Is displayed on the display unit or the like so as to indicate to the operator.

Next, a method of determining image data outside the print area in the digital copying machine of the present embodiment will be described with reference to FIG.
A description will be given of the flow of image data at the time of a prescan operation with reference to FIG. First, at the time of pre-scanning, an image is read by the image reading unit 110, image processing is performed by the image data input unit (document reading unit) 40, and then image data is sent to the area determination unit 48 through the image data bus.

In the area determination section 48, first, in the main scanning direction, whether the input image data is generated outside the image data allowable area width set for each printing paper size, or not.
Check every line. Next, in the sub-scanning direction, similarly, it is checked line by line whether or not the input image data is generated outside the image data allowable area length set for each printing paper size. If image data is detected outside the printing area (image data allowable area) in the main scanning direction or the sub-scanning direction, a flag indicating that there is data outside the area is set, and the scanning substrate unit 5 is set.
By 0, a warning of occurrence of print out is displayed.

In the print mode, image data is sent from the printer IF interface 47 to the area determination section 48 through the image data bus, and the operations after the area determination are performed in the same manner as the above-described copying operation. If image data is detected outside the print area, a warning display command is transferred to the host computer via the printer interface 47, and a warning display is performed on the host computer.

Next, in the digital copying machine according to the present embodiment, a method of temporarily storing image data in a memory during a pre-scan operation and then determining image data outside a print area will be described with reference to FIG. I do. First, at the time of pre-scanning, an image is read by the image reading unit 110, image processing is performed by the image data input unit (document reading unit) 40, and then the image memory 43 (43) is passed through the image data bus.
The image data is passed to e). Subsequently, the area determination unit 48 sequentially checks on the image memory whether image data has been written outside the print area in the main scanning direction / sub-scanning direction set on the image memory. When image data is detected outside the printing area (image data allowable area) in the main scanning direction or the sub-scanning direction, a flag indicating that there is out-of-area data is set, and the operation board unit 50 causes print out. Is displayed.

In the print mode, image data flows from the printer IF interface 47 to the image memory 43 via the image data bus, and the operations after area determination are performed in the same manner as the above-described copying operation. If image data is detected outside the print area, a warning display command is transferred to the host computer via the printer interface 47, and a warning display is performed on the host computer.

Although the case where the processing is performed at the time of pre-scan has been described with reference to FIG. 4, the processing can be performed at the time of scanning.

Next, FIG. 5 (a-1) and FIG.
The configuration of the area determination unit 48 that determines out-of-area data based on the flow of image data at the time of prescan using 2) will be described. When the prescan starts and the image data starts to flow (P1 position), the entire area on the main scan is outside the area, and the output of the selector 2 becomes H. Then, the image data is input to the image data buffer and the buffer is shifted and output. If there is data, the output indicating the presence of image data outside the print area becomes H. Next, when the position P2 is reached, the area at both ends in the main scanning is outside the area, and the output of the selector becomes H. Then, the image data is input to the image data buffer, the buffer is shifted and output, and the preset image data allowable area buffer is also shifted and output. When both data become H output at the same time, the output indicating that there is image data outside the print area is output. H. Thereafter, when it reaches the position of P3, all the areas on the main scanning are outside the area again, the output of the selector 2 becomes H, and the same processing as the position of P1 is performed.

Next, FIGS. 5 (b-1) and 5 (b-
The configuration of the area determination unit 48 that determines the image data outside the print area after temporarily storing the image data in the memory during the pre-scan operation by using 2) will be described. After the prescan is started and the image data enters the memory, following the completion of the prescan, the outside of the print area is sequentially addressed by the address circuit outside the print area to read the memory, and the output of the selector is set to H. Then, when the output from the memory becomes H, the output with the image data outside the print area becomes H. In this way, by addressing only the outside of the print area by the address circuit, it is possible to make a determination in a short time.

Although the case where the out-of-area data is determined at the time of the copy operation has been described with reference to FIG. 5, the same applies to the case of the printer operation.

Next, with reference to FIG. 6, a description will be given of a method for judging dirt or dust with respect to image data or a document in an area outside the printing area. In the method of FIGS. 4A and 4B, when checking for image data outside the print area, as shown in FIG. 6A and FIG. Although the image data is stored in the image data allowable area, when the image data input unit (original reading unit) 40 reads dirt or dust on the original, the size of the image data is smaller than a certain standard. In this case, it is determined that the area is dirty or dusty, and the flag indicating that there is data outside the area is not set. The method of determining dirt or dust is determined to be image data when n dots or more continue in the main scanning direction and m dots or more in the sub-scanning direction.
If it is less than that, it is judged as dirt or dust. Here, n and m are arbitrarily settable parameters.

Next, with reference to FIG. 7, a description will be given of a method of determining the case where the magnification of the image is set and the case where the rotation is set. When the image data outside the print area is detected by the method shown in FIGS. 4A and 4B, if the magnification is set, the zoom processing is performed as shown in FIG. 7A. After performing the image scaling processing by the circuit 41f,
The area determination section 48 detects whether image data exists outside the print area according to the final print mode. When the rotation is set, as shown in FIG. 7B, after the image rotation processing is performed by the image rotation section 49, the area determination section 48 performs the printing outside the printing area according to the final printing mode. It is detected whether or not there is image data.

Next, with reference to FIG. 8, a description will be given of a determination method in the case where the sheet binding margin is set and the case where the one set / two copy mode is set. FIG. 4 (a)
When image data outside the print area is detected by the method of FIG. 4B, if image shift is set, the image data is sent to the area determination unit 48 or written to the image memory 43e. At this time, after performing the image shift processing as shown in FIG. 8A, the area determination unit 48 detects whether image data is present outside the print area by the final print mode. When the one-set two-copy mode is set, the setting of the image data allowable area width in the main scanning direction and the image data allowable area width in the sub-scanning direction of the area determination unit 48 is shown in FIG. Perform as shown. Alternatively, setting outside the print area in the main scanning direction / sub-scanning direction in the image memory 43e is performed as shown in FIG. 8B. Then, it is detected whether there is image data outside the print area.

Next, the control for determining the image data outside the print area in the digital copying machine of the present embodiment will be described with reference to the flowcharts of FIGS. In the flow of prescan 1 shown in FIG. 9, a method of determining out-of-area data will be described in the flow of image data during the prescan operation. First, the outside of the area in the main scanning direction and the sub-scanning direction is set (step F1), and if there is the setting of one set and two copy modes (step F2), the outside of the area in the sub-scanning direction is reset (step F3). If there is a magnification setting (step F4), the magnification processing is performed (step F5). If the image rotation is set (step F6), the rotation processing is performed (step F7), and the image shift setting is made. In step F8, a shift process is performed (step F9), and a prescan is started (step F10).
Then, it is determined whether the read one-line image data in the main scanning direction is outside the area (step F11), and if there is data outside the area, a flag indicating that there is data outside the area is set (step F12). Similarly, in the sub-scanning direction, it is determined whether the read image data is outside the area (step F13), and if there is data outside the area, a flag indicating that there is data outside the area is set (step F14).
The above steps are repeated one line at a time in the main scanning direction until the end of the prescan (step F15).

In the flow of the prescan 2 shown in FIG. 10, a method of judging out-of-area data after image data is once stored in the memory during the prescan operation will be described. First, the outside of the area in the main scanning direction and the sub-scanning direction is set (step F21), and if there is a setting of one set and two copy modes (step F22), the outside of the area in the sub-scanning direction is reset (step F23). If there is a magnification setting (step F24), a magnification process is performed (step F25). If an image rotation is set (step F26), a rotation process is performed (step F27), and an image shift setting is made. (Step F28) Shift processing is performed (Step F2).
9), pre-scan is started (step F30). Then, writing to the memory (step F31) is repeated until the end of the prescan (step F32). When the image data has been written to the memory, it is determined whether there is image data outside the print area (step F33). If there is data outside the area, a flag indicating that there is data outside the area is set (step F34).

In the above description, the control of the prescan 1 and the prescan 2 has been described by the copy operation, but the same applies to the print operation.

Next, a method of displaying a warning will be described with reference to the display flow of FIG. In the middle of the display flow,
It is checked whether a flag indicating that there is out-of-area data is set (step F40). Then, if the flag is set, it is determined whether the mode is the print mode (step F4).
1) If the print mode is set, a print out warning display command is transferred to the personal computer (step F).
42). If the mode is not the print mode (copy mode), a warning of print out is displayed (step F43).

[0070]

As described in detail above, according to the first aspect of the present invention, when copying or printing, it is determined whether or not there is image data outside the print area by the image area and the print area of the output paper. Detecting the error and, if it is detected, displaying a warning of the occurrence of print out, a printing error can be prevented.

According to the second aspect of the present invention,
The presence / absence of image data outside the printing area can be detected in real time.

According to the third aspect of the present invention,
By temporarily storing the image data in the memory and then detecting the presence or absence of the image data only outside the print area, the presence or absence of the image data outside the print area can be detected in a short time.

According to the fourth aspect of the present invention,
When detecting the presence / absence of image data outside the print area, erroneous detection can be prevented by determining dirt or dust other than the output.

According to the fifth aspect of the present invention,
When image scaling is set, erroneous detection can be prevented by judging image data outside the printing area with the final data (printing area and image area) subjected to scaling processing.

According to the present invention described in claim 6,
When image rotation is set, erroneous detection can be prevented by determining the image data outside the print area with the final data subjected to the rotation processing.

According to the present invention described in claim 7,
In the case where the binding margin of the paper is set, erroneous detection can be prevented by determining the image data outside the print area with the final data subjected to the binding margin processing.

Further, according to the present invention, when the one-set two-copy mode is set,
By determining the image data outside the print area with the final data after performing the one-set two-copy process, erroneous detection can be prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of an image forming apparatus according to an embodiment of the invention.

FIG. 2 is a block diagram illustrating a configuration of an image processing unit included in the digital copying machine according to the embodiment.

FIG. 3 is a diagram for explaining a state in which the operation of each unit of the entire apparatus is managed by a central processing unit (CPU) in the digital copying machine of the embodiment.

FIG. 4A is a diagram for explaining a method of determining image data outside a print area in the digital copying machine according to the embodiment with reference to a flow of image data during a prescan operation, and FIG. FIG. 7 is a diagram for describing a method of determining image data outside a print area after temporarily storing image data in a memory during a prescan operation in the digital copying machine according to the embodiment.

FIGS. 5A and 5B are diagrams for explaining the configuration of an area determination unit that determines out-of-area data based on the flow of image data at the time of prescan; FIG.
1) and (b-2) are diagrams for explaining a configuration of an area determination unit that temporarily stores image data in a memory during a pre-scan operation and determines image data outside a print area.

FIG. 6A is a diagram for explaining a method for determining dirt or dust on image data or a document outside a print area, and FIG. 6B is an enlarged view of a part of FIG. It is.

FIG. 7A is a diagram for explaining a method of determining image data in an area outside a print area when image scaling is set, and FIG. 7B is a diagram when image rotation is set; FIG. 9 is a diagram for describing a method of determining image data in an area outside a print area of FIG.

FIG. 8A is a diagram for explaining a method of determining image data in an area outside a print area when an image shift is set, and FIG. 8B is a diagram illustrating a one-set two-copy mode set; FIG. 7 is a diagram for describing a method of determining image data in an area outside a print area in the case.

FIG. 9 is a flowchart illustrating a method of determining out-of-area data in the flow of image data during a prescan operation.

FIG. 10 is a flowchart illustrating a method of determining out-of-area data after image data is once stored in a memory during a prescan operation.

FIG. 11 is a flowchart illustrating a method of displaying a warning.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Copier main body 111 Original table 110 Image reading part 112 Automatic two-sided automatic document feeder 113 First scanning unit 114 Second scanning unit 115 Optical lens 116 CCD line sensor 210 Image forming part 211 Paper feed mechanism 212 Registration roller 213 Transfer conveyance Belt mechanism 214 Drive roller 215 Follower roller 216 Transfer transport belt 217 Fixing device 218 Transport direction switching gate 219 Discharge roller 220 Discharge tray 221 Switchback transport path 222a, 222b, 222c, 222d Photoconductor drum 223a, 223b, 223c, 223d Charging 224a, 224b, 224c, 224d Developing device 225a, 225b, 225c, 225d Transfer discharger 226a, 226b, 226c, 226d Cleaning device 2 7a, 227b, 227c, 227d Laser beam scanner unit 228 Paper suction (brush) charger 229 Static eliminator 240a, 240b, 240c, 240d Polygon mirror (deflection device) 241a, 241b, 241c, 241d fθ lens 242a, 242b, 242c , 242d, 243a,
243b, 243c, 243d Mirror P Paper Pa First image forming station Pb Second image forming station Pc Third image forming station Pd Fourth image forming station 40 Image data input section (document reading section) 40a Color CCD 40b Shading correction circuit 40c Line alignment unit 40d Sensor color correction unit 40e MTF correction unit 40f γ correction unit 41 Image processing unit 41a Monochrome data generation unit 41b Input processing unit 41c Area separation unit 41d Black generation unit 41e Color correction circuit 41f Zoom processing circuit 41g Spatial filter 41h Halftone processing unit 42 Image data output unit 42a Laser control unit 42b, 42c, 42d, 42e Laser scanner unit 43 Image memory 43a, 43b, 43c, 43d Hard disk Disk (rotation storage medium) 43e delay buffer memory (semiconductor memory) 44 central processing unit (CPU) 45 image editing unit 46, 47 external interface unit 48 area determination unit 49 image rotation unit 50 operation board unit

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G06T 3/60 H04N 1/00 B 5C076 H04N 1/00 1/393 1/393 G03G 21/00 382 F-term (Ref.) AB08 AB17 AB22 AB41 AB42 AC02 AC04 AC06 AC22 AC24 AC58 AE03 AE15 AF10 AF11 5C076 AA21 AA22 AA24 AA37 BA02

Claims (8)

[Claims] 1. An image forming apparatus for performing a copying operation of a document or a printing operation of an image. A print area setting means for setting a print area on paper, a detection means for detecting the presence or absence of an image area outside the print area, and a warning display for giving a warning display of occurrence of print out when an image area is detected outside the print area. An image forming apparatus provided with an image processing section having means. And means for detecting the presence or absence of an image area outside the print area, wherein the image area outside the print area is provided by image data flowing when a document is scanned by the scanner unit or image data flowing when print data is input. The image forming apparatus according to claim 1, wherein the presence or absence of the image is detected. And means for detecting the presence or absence of an image area outside the print area. The means for detecting the presence or absence of an image area outside the print area is based on the image data once stored in the memory when the original is scanned or the image data once stored in the memory when print data is input. The image forming apparatus according to claim 1, wherein the presence or absence of the image is detected. 4. A means for detecting the presence or absence of an image area outside the print area determines that the area occupied by the image data is an image when the size is equal to or larger than a certain reference, and when the area is smaller than the certain reference. 4. The image forming apparatus according to claim 1, wherein the image forming apparatus determines that the image forming apparatus is dirty or dust. 5. The image area detecting means according to claim 1, wherein, when scaling of the image is set, the image area is detected based on the image data after the scaling processing. Image forming apparatus. 6. The image according to claim 1, wherein the image area detecting means detects an image area based on the image data after the rotation processing when the rotation of the image is set. Forming equipment. 7. The image area detecting means according to claim 1, wherein, when a binding margin of the sheet is set, the image area is detected based on the image data after the shift processing for the binding margin. An image forming apparatus according to any one of the above. 8. The image area detecting means includes one set of two
If the copy mode is set. The image area is detected based on the image data after one set and two copy processes, and the print area setting means is provided. When the 1 set 2 copy mode is set. The image forming apparatus according to any one of claims 1 to 7, wherein a print area for one set and two copies is set.