JPH02155372A - Image forming apparatus control method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method of controlling an image forming apparatus which is a so-called digital copying machine with a facsimile function added thereto, and particularly relates to a control method during facsimile transmission.

[Prior art]

2. Description of the Related Art In recent years, digital copying machines have been proposed that are configured by combining a document reading device that digitally reads document images and a page printer (eg, a laser printer) that records images page by page at a predetermined resolution.

When such a digital copying machine is used, in addition to simple copying operations, it is also possible to copy an edited image, or to copy an image that has been processed by adding some processing.

Further, this digital copying machine can be used as a hard copy device for an information processing device such as a personal computer, or can be used as a facsimile device by adding a communication function.

By the way, digital copying machines can generally read documents up to A3 size, but the standard receivable size for conventional facsimile machines is 84 size or A4 size. For this reason, if the size of the original to be sent is larger than the receivable size with an image forming device that is a digital copier with a facsimile function added, it is necessary to reduce the size of the original to be sent and send it to the receiving side. Such scaling during facsimile transmission is realized by electrical scaling, which is the same as when making a reduction copy with a digital copying machine.

Additionally, digital copiers generally have a high resolution, and the line density of the read image is set at 15.7 lines/mm (400 dpi), but on the other hand, the line density of the transmitted image of a G3 standard facsimile machine is usually , 8 lines/m in main scanning direction
m, 7.7 lines/m in the sub-scanning direction m, 3.85 lines/m
It is set to mm. Therefore, in an image forming apparatus in which a facsimile function is added to a digital copying machine, it is necessary to convert the line density of 15.7 lines/mm into a line density for facsimile at the time of facsimile transmission.

Therefore, conventionally, this type of image forming apparatus incorporates a dedicated circuit for realizing such density conversion, but if it is attempted to control linear density conversion and magnification change through separate routes, the circuit configuration inevitably becomes The problem was that it became complicated.

〔the purpose〕

The present invention has been made to solve the problems of the prior art, and it is an image forming method that uses the variable magnification function of the document reading section to enable facsimile transmission without creating an external circuit for image density conversion. The purpose is to propose a control method for the device.

〔composition〕

The present invention performs vA density conversion by controlling the magnification m function for reducing/enlarging the original image, for example, 15.7 lines/m
51% when converting the linear density of m to 8 lines/mm
Since the image is read after being reduced at a magnification ratio of , there is no need to provide a dedicated circuit for density conversion processing.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an image forming apparatus according to an embodiment of the present invention.

This image forming apparatus includes a document conveying device 100 that conveys a document to a contact glass, a scanner 200 that decomposes an image of the document positioned on the contact glass at a predetermined resolution and converts it photoelectrically, and an image read by the scanner 200. It mainly consists of a copying apparatus 300 that records on recording paper of any size stored in three paper feed cassettes, and has basically the same configuration as a well-known so-called digital copying machine.

In the document 1 forwarding device 100, documents placed on a document table 101 are fed out one by one by a feed roller 102, and are positioned on a predetermined surface of a contact glass 201 by a conveyor belt 103. When the image of the original is read, the original is transferred to the first general transport belt 103.
is removed from the contact glass 201 and discharged onto the discharge tray 104.

In the scanner 200, an image of a document positioned on a contact glass 201 is scanned in the direction of the arrow by an optical system 202, and the image obtained by scanning (hereinafter referred to as scan light) is transmitted to a line image sensor. It is imaged at 203. The line image sensor 203 decomposes the scanning light of the scan line of the optical system 202 into a predetermined number of pixels and photoelectrically converts the data of each pixel, thereby forming electrical image information. The resolution of this scanner 200 is 15.7 lines/
rnm (400dpi).

In the copying apparatus 300, a drum-shaped photoreceptor 302 is irradiated with laser light output from a laser writing section 301 that scans laser light modulated according to image information. Note that the recording resolution of the copying apparatus 300 is set to the same resolution as that of the scanner 200.

This photoreceptor 302 is rotated in the direction of the arrow, and
Its surface is uniformly charged by the charger 303, and the charged surface is exposed to laser light to form an electrostatic latent image corresponding to the recorded image (image information). Due to the toner phenomenon.

On the other hand, the recording paper stacked in the selected one of the three paper feed cassettes 305, 306, 307 is moved to the top by the paper feed rollers 308, 309, 310 corresponding to the respective paper feed cassettes 305, 306, and 307. The sheets are sent out one by one starting from the one at the position. The recording paper sent out by the paper feed rollers 308, 309, and 310 in this manner is sent to the photoreceptor 302 by the registration roller 311 at the timing when its leading edge coincides with the leading edge of the toner image.

The recording paper sent to the photoconductor 302 is brought into close contact with the photoconductor 302 by a transfer charger 312 and a toner image is transferred thereto, and then separated from the photoconductor 302 by a separation charger 313, and then the toner image is transferred by a printer 314. fixed on its surface. Then, the recording paper that has been fixed is conveyed to a discharge roller 317 via a distribution section 315 and a reversing section 316, and is discharged outside the machine.

The recording paper discharged outside the machine is sorted 318 into either a stacker 319 that stacks recording paper on which a copy image is recorded during a copying operation, or a stacker 320 that stacks recording paper on which a received image is recorded during facsimile reception. Crabs are sorted.

Further, the distribution section 315 sorts the recording paper on which the image has been recorded to either the reversing section 316, the ejection roller 317, or the conveying section 321. This is for conveying the recorded paper to the registration rollers 311 again.

Note that the residual toner on the surface of the photoreceptor 302 is removed by the cleaning section 322, and the residual charge is removed by the static elimination lamp 3.
removed by 23.

FIG. 3 is a block diagram schematically showing the control system of this image forming apparatus.

In the same figure, the output image signal of the line image sensor in the scanner 200 section is amplified to a predetermined amplitude by an AGC (variable gain side? II) amplifier, and converted into a digital signal of a predetermined number of bits by an analog/digital converter to form an image. It is added to the processing/control unit 11.

The image processing unit/control unit 11 includes an optical system 2 of the scanner 200.
Shading correction processing that corrects variations in the level of image signals caused by variations in the characteristics of 02 and the light receiving characteristics of each bit of the line image sensor 203, and the difference between the image reading characteristics of the scanner 200 and the human visual characteristics. γ correction processing that corrects and converts the image read by the scanner 200 into a visually optimal image; MTF correction processing that eliminates blurred images; It performs halftone processing to appropriately render an image, character/halftone separation processing to separate a character portion to be binarized and an image to be halftone processed, and various other image processing. Further, the image information processed in this manner is sent to the laser printer 12 section, whereby the laser diode 1B generates laser light modulated according to the image signal (image information). Note that this laser diode 18 is connected to the copying machine 30.
It is provided in the laser writing section 301 of No. 0. The image processing/control unit 11 also executes scaling processing for reducing and enlarging the image.

The image processing/control unit 11 is provided with an operation display unit (not shown), which includes operation keys necessary when the image forming apparatus is used as a copying machine or a facsimile machine, and displays operating conditions, operating procedures, and the like. That is, the operation section includes, for example, a start key for starting a facsimile transmission operation, a copy key for starting a copying operation, a stop key for stopping a copying operation, and a key for inputting numerical data such as the number of copies and a telephone number. The numeric keypad includes abbreviated keys for entering telephone numbers, mode keys for setting various operating modes of the facsimile machine, and guidance keys for selecting selection items displayed on the display.

Further, as a display device, a liquid crystal display device or the like having a high degree of freedom in display is used to display message information of operating procedures, numerical values input using a numeric keypad, the actual number of sheets, etc.

The facsimile control unit 13 executes transmission control procedures for facsimile transmission, compresses and expands images, transmits signals via a modem, and receives signals via a modem.

Note that human data from the operation display section is notified to the facsimile control section 13 via the image processing/control section 11, and display data from the facsimile control section 13 to the operation display section is notified to the operation via the image processing/control section 11. Output to the display section.

Next, the operation when this image forming apparatus is used as a facsimile machine will be explained.

In the facsimile transmission procedure, as shown in Figure 4, the sending side calls the receiving side (calling signal CNG), and once the line is established, the receiving side indicates that it is a non-voice terminal. After responding with the called station identification signal CED, the digital identification signal DIS indicates the receiving function of the own station.
respond.

The sending side selects the function to be used for the facsimile transmission from the content of the received digital identification signal DTS, displays it in the digital command signal DC3 to notify the receiving side, and sets the modem to the transmission speed selected at that time. Set the speed 1
．． Execute 5 seconds of training (Training Check TCP).

If the result of this modem training is good, the receiving side responds with a reception preparation confirmation signal CFR to the transmitting side and prepares to receive images at the modem speed at that time.

Upon receiving the reception preparation confirmation signal CFR, the transmitting side transmits the training signal TNG corresponding to the modem standard training sequence corresponding to the set modem speed, transmits the image information MSG of the first page, and then transmits the subsequent image information MSG. If there is an image, a multi-page signal MPS is transmitted.

If the receiving side can properly receive the received image at that time, it responds with a message confirmation signal MCF and prepares to receive the next page of images.

The transmitting side, which has received the message confirmation No. 16 MCF, transmits the training signal TNG again, then transmits the image information of the second page, and then transmits the procedure end signal EOP when the transmission ends.

The receiving side responds with a message confirmation signal MCF in the same way as for the first page, and when the transmitting side receives this message confirmation signal MCF, it transmits a disconnection command signal DCN to disconnect the line and end the facsimile transmission.

Also, on the receiving side that received this disconnection command signal DCN,
Cut the line.

Now, when the operator places the original to be transmitted on the document table 101 of the document feeder 100, selects the facsimile mode on the operation display section, inputs the destination, and turns on the start key to start the transmission operation, the image processing/ The control unit 11 transfers data input by the operator to the facsimile control unit 13.
It also instructs the document conveying device 100 to forward the document to be sent and start the facsimile transmission operation. As a result, the scanner 200 starts scanning.

Now, the operator selects the immediate transmission mode and selects one destination.
If one is selected, the facsimile control unit 12 transfers the destination's telephone number to the network control device to make a call to the destination, and once the line is established, executes the transmission control procedure described above to determine the receiving function of the destination. Then select the one you want to use and notify the recipient.

At this time, the receivable size of the destination is compared with the size of the original to be sent, and if the former is smaller than the latter, the image of the original to be sent is reduced at a scaling factor according to the receivable size of the destination, and then sent. . The relationship between the receivable size, the size of the transmitted document, and the variable magnification ratio is shown in the table.

Please note that the table above lists the five types of sizes that can be received (B4 size, ~B size).
6 size), but the standard receivable size for facsimile machines is 84 size or A4 size.

When sending a facsimile, the document to be sent is also scanned by the scanner 20.
0 at a high resolution of 15.7 lines/mm, it is necessary to convert this to a density for facsimile transmission. In other words, the cotton density is 15.7 lines/mm, 8 lines/mm in the main scanning direction, and 7.7 lines/mm in the sub-scanning direction.
Density conversion processing is performed to books/mm. This density conversion process can be performed using a scaling function, for example, 15.7
When converting a linear density of 8 lines/mm to 8 lines/mm, read the image in the same way as when reducing the magnification ratio of 51%, and when converting to a magnification of 7.7 lines/mm, read the image at 49%. Just read the image in the same way as when reducing it.

In order to perform such scaling and linear density conversion, the facsimile control unit 24 executes processing as shown in FIG.

In this process, first, iz is placed on the contact glass 201.
The size of the transmitted original is determined. That is, in step S1, the original is scanned once, and the original size is read from the original on the contact glass.Next, in step S
2, the original size is A3°B4. Determine either A4. If it is determined as 83 in this step S2, step S
, and if it is other than A3, the process advances to step S3. In this step S3, it is determined whether the document size is B4 or not. When the document size is B4, the process proceeds to step S7, and when the document size is other than B4, the process proceeds to step S4.

In this step S4, since the document was selected to be A4 size or smaller in step S3, it is only necessary to change the reading density and send it to the destination.

Therefore, a variable magnification of 51% in the main scanning direction and 4996 in the sub-scanning direction is set, the data is read at that magnification in step S, and the read data is transmitted in step 36.

When it is determined in step S3 that the document size is 84, the size of the received document is determined in step S.

If it is determined in step S that the received size is not A4, it is assumed that the received size is B4, and in step S4, the magnification ratio is set to 51% in the main scanning direction and 49% in the sub-scanning direction. S5, step S is performed. Furthermore, when the received size is determined to be A4, it is necessary to reduce the size from B4 to A4, so a variable magnification ratio of 42% in the main scanning direction and 40% in the sub-scanning direction is set. Then, in step S, the image is read at that magnification and transmitted in step S6.

Furthermore, if the document is determined to be A3 in step S2 and the process proceeds to step S, the received size is determined in this step. Then, when the determined received size is 84, a magnification ratio of 44% in the main scanning direction and 42% in the sub-scanning direction is set in step S1°, and in step S5. It is transmitted through step S6. Furthermore, when the received size is determined to be A4 in step S, a variable magnification of 36% in the main scanning direction and 35% in the sub-scanning direction is set in step S11, and the data is similarly transmitted via step S and step S6. .

Thus, in step S, step S4. Step Sa+Step S. By reading the document at the magnification ratio set in step S and step S, it is possible to perform both density magnification change and reduction.

As described above, according to the above embodiment, the cotton density can be easily changed by using the function of the scanner 200 section for independently varying magnification in the vertical and horizontal directions. This allows facsimile transmission from a digital copying machine without providing a density conversion processing circuit.

〔effect〕

As is clear from the above description, according to the present invention, density conversion is performed by controlling the scaling function for reducing/enlarging the original image, so a density conversion processing circuit is provided separately from the scaling processing circuit. There is no need to attach it, and there is an effect that the circuit configuration can be simplified.

[Brief explanation of the drawing]

The figures are all for explaining the present invention in detail. Figure 1 is a flowchart showing the reading procedure at the time of transmission, Figure 2 is an explanatory diagram showing an example of a copying machine with a conversion function, and Figure 3 is a copy thereof. FIG. 4 is a block diagram showing a general control system of the machine, and a timing chart showing an example of a facsimile transmission procedure. 11... Image processing/control unit, 12...
. . . printer section, 13 . . . facsimile control section, 200 . . . scanner section.

Claims (1)

[Claims] A document reading means having a variable magnification function for converting and reading a document image into an electrical signal and performing reduction/enlargement, a copying means for recording an image signal output from the document reading means, and a copying means from the document reading means. A method for controlling an image forming apparatus comprising a transmission means for transmitting an output image signal via a public line, wherein the line density conversion of the read image set when the transmission means is used is performed by the document reading means. A method for controlling an image forming apparatus, characterized in that the method is performed using a variable magnification function.