JPH0797802B2 - Image forming device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus, and in particular, an offline method capable of network connection with another apparatus and printing an image read by the apparatus itself. The present invention relates to an image forming apparatus having both a copying function and an online printer function for inputting and printing an image signal generated in another apparatus into the apparatus itself.

[Conventional technology] It is no exaggeration to say that the wave of OA has evolved based on LSI technology. Due to the remarkable progress of semiconductor integrated technology in recent years and the synergistic effect of computer technology, the functions of various OA equipment have been significantly improved. The basic LSI is a so-called one-chip micro computer. As is well known, it is needless to say that the rapid reduction of the chip cost has accelerated the spread of the chip. Now that factory automation has spread to factories and worksites, and labor saving has been achieved for some time, we are now focusing on automating office work in offices.
That is, office automation has been screamed and various OA devices have been developed. Among them, the growth of copiers is by far the highest, maintaining more than 20% growth every year. Generally, a widely used copying apparatus irradiates an original with an exposure lamp and directly forms an image of the reflected light on a photosensitive drum (hereinafter referred to as an analog copying apparatus). These include personal mini-copiers, general office medium-speed machines, and mass-copy high-speed machines according to the purpose of use. Further, in recent years, a so-called digital copying apparatus has been realized in which an image is electrically read instead of an analog copying apparatus and the image quality thereof is electrically improved or the image is enlarged / reduced electrically. In the analog copying apparatus, the reading section and the printing section of the original were inseparably integrated by an optical system. However, once the image is converted into an electric signal, it can be freely handled later. It becomes possible to easily store the image in the image file or transmit the read image or the stored file image to the image printer at a remote place, which is extremely convenient in constructing the image OA system. Of course,
It is also possible to perform off-line copying with a digital copying machine. In this way, the systemization of OA especially using LAN (Local Area Network) is rapidly progressing at present. In the near future, most of the analog copying machines may be replaced by digital copying machines. However, at present, the analog copying apparatus is still superior in price and image quality to the digital copying apparatus, and the analog copying apparatus is more advantageous as far as offline copying is performed. Therefore, it is desired to realize an inexpensive and easy-to-use image forming apparatus which can be used efficiently by other devices (reader, personal computer) while performing offline copying.

[Purpose] The present invention has been made in the background of the above-mentioned conventional technology, and its object is to take an offline copying function into consideration in view of the fact that OA equipment is generally connected to the same power line for use. Another object of the present invention is to provide an image forming apparatus that has an online printer function and is easily connected to other OA equipment for use.

Embodiments Embodiments according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a block diagram of an OA system including an analog / digital image forming apparatus 51 of the embodiment. In the figure,
Reference numeral 51 is an analog / digital image forming apparatus (hereinafter referred to as "image forming apparatus"), and 53 to 56 are solid-state image pickup elements (CCD) for document images.
Etc.), and a digital image reading device (reader) for transmitting the read digital image signal, 57 to 60 are sorters (or sorters / collators) for sorting and stacking output sheets that have been copied offline or printed online. Is a bank in which a plurality of sorters 57 to 60 are connected in a chain, 100 is a modem for performing data (image data) communication via an AC power line, and 41 is a modem using the RS232C communication method.
It is an RS232C interface that interfaces 100.

The image forming apparatus 51 can be used as an off-line copying apparatus of the type in which an original is illuminated by the exposure lamp 3 and the reflected light is imaged on the photoconductor drum 20 through the mirrors 4 to 9 and the zoom lens 11, and also the RS232C. By inputting the digital image signal read by the readers 53 to 56 via the interface, the digital image signal is transferred to the photoconductor drum 20 via the erase lamp / writing head 15 such as an LED array, a liquid crystal shutter or a DMD element. It can also be used as an online digital printer that writes on top. Therefore, it can be used as an online digital copying machine by connecting to the readers 53 to 56.

Sorters 57 to 60 are output sheets if assigned, for example, sorter 57 for reader 53, sorter 58 for reader 54, sorter 59 for reader 55, sorter 60 for reader 56, and so on. Mixing can be prevented and this OA system can be operated efficiently. That is, the components of the OA system do not have to be placed in the same room or the same place. Can be placed at The person who copied from each reader should just go to his sorter stacker to get a copy. In this way, a plurality of people can apparently share the image forming apparatus 51, which has conventionally been usable only at one place, at each place at the same time. Moreover,
For example, the operation of the system can be made more rational by giving the reader 53, which is placed on the side of the desk of a person who is doing important work, the highest priority as an external device. On the other hand, in the case where the main body of the image forming apparatus 51 is used for off-line copying, the stacker 64 for the main body is used as a discharge unit for the output sheet, or when a large number of copies are made, another unit is operated by the main body operation unit (not shown) The sorters 57-60 can be exclusively used by prohibiting the interrupts from the readers 53-56. Of course, the method of assigning Sota Stutsuka is not limited to this. For example, each sorter stacker may be assigned to each information distribution destination. This way
For example, an image read by the reader 53 is output to, for example, the sorter 60 by designating the destination. Therefore, the efficiency of copy distribution as an information transmission means is improved, and the system application is further expanded.

FIG. 2 is a sectional view of the optical system / mechanical portion of the image forming apparatus 51. The function of the image forming apparatus 51 is mainly a paper feeding / conveying system,
Exposure system, optical system, writing head (printer head),
It consists of a process system installed around the drum and an electric control system.

First, the details of the offline copying operation will be described with reference to FIG. An operator who wants to make an off-line copy opens the platen cover 1 and sets an original (original).
In the case of reducing or enlarging, a scaling factor is set as necessary with a scaling key from an operation unit (not shown). Further, the number of offline copies, auto / manual selection of density, offline copy mode, and single-sided or double-sided selection are made with respective keys. For now, let's proceed with the example of double-sided copying.
Select the simplex / duplex selection key in duplex mode and turn on the copy start key. Then, the halogen lamp 3 for exposing the original is turned on, the photosensitive drum 20 is rotated, and the charging corona 13 is energized. The halogen lamp 3 and the first mirror 4 operate in the same manner, and scan the original surface in the sub-scanning direction (rightward in the drawing). The reflected light is the first mirror 4, the second mirror 5, the third mirror 6, and the zoom lens.
4th mirror 7, 5th mirror 8 and 6th mirror 9 through 11
An image is formed on the surface of the photoconductor drum 20 through the optical axis of. The image formation (latent image) on the surface of the photoconductor drum 20 is further removed by the erase lamp / writing head 15 in accordance with the size of the paper (transfer paper) so that the surface potential of the portion not covered by the latent image is removed. . In the developing device 17, toner adheres to the area on which the latent image is formed, and the latent image is visualized. On the other hand, the transfer paper fed from the selected upper cassette 22 or lower cassette 24 is waiting by the registration roller 30. The registration roller 30 rotates at a predetermined timing to align with the image on the surface of the photoconductor drum 20, and the image on the surface of the photoconductor drum 20 is transferred to the transfer paper by the bias of the transfer corona 14. To be done. Next, the transfer sheet is separated from the photoconductor drum 20 by the sheet separating roller 31, and is conveyed to the fixing section (fixing heater roller) 33 by the sheet conveying belt 32. Heat and pressure are applied here, and the toner is fused. Next, since the paper guide plate 34 is in the double-sided mode, the transfer paper is guided to the double-sided paper discharge roller 37 and is once conveyed to the double-sided paper discharge tray 38. The paper carried here slides naturally downward by gravity and is gripped by the intermediate cassette guide roller 39, and is stored in the intermediate cassette 26. It should be noted that the double-sided paper ejection tray 38 will not be stocked with paper. It slides down one by one. In this manner, the sheets of paper copied on the front surface are stored in the intermediate cassette 26 by the number of sheets set. On the other hand, the image on the surface of the photosensitive drum 20 that has been transferred is cleaned by the cleaner 19.
The surface of 20 is cleaned, and the residual toner attached to the surface of the photoconductor drum 20 is removed. Further, the charge eliminating lamp 18 is irradiated to remove the residual charge on the surface of the photosensitive drum 20. Next, it is newly charged by the charging corona 13,
A predetermined surface potential is applied on the surface of the photoconductor drum 20, and then a new image (latent image) is formed. When the copy on one side is completed in this way, the operator changes the original and performs the next copy operation (back side copy). When the original is set and the copy start key is newly turned on, the back side copy operation starts. The intermediate cassette feed roller 25 rotates at a predetermined timing to feed the intermediate cassette 26. The paper is reversed by the intermediate cassette paper guide plate 29 and gripped by the registration roller 30. In order to align the leading edge of the image, it waits at a predetermined timing until a start signal is received. The registration roller 30 rotates at a predetermined timing to align the leading edge of the image, and the image formed on the surface of the photoconductor drum 20 is transferred. At this time, the transfer corona 14 is urged at a predetermined timing to transfer the image to the back surface. It is separated from the photoconductor drum 20 by the paper separating roller 31, and is conveyed to the fixing unit 33 by the paper conveying belt 32. The toner is fused here. Next, the paper guide plate guide roller 40
Be held in. The paper guide plate 34 is now guided so as to be guided to the paper output tray 36, and the transfer paper copied on both sides is output to the paper output tray.
Stocked to 36. In this way, the double-sided copying process is completed. In the case of a normal one-sided copy, the guide plate 34 guides the transfer paper to the paper output tray 36. Further, the paper fed from the upper cassette 22 or the lower cassette 24 at the time of copying only the back side is urged only by the paper conveying system and transferred to the intermediate cassette 26 in a blank state. At this time, the image forming system is not operated at all, and only the system that feeds the paper from the paper feed cassette of the upper cassette 22 or the lower cassette 24 and conveys the paper to the intermediate cassette 26 operates.

An automatic exposure function is provided to improve copy quality. This is to control the surface potential on the surface of the photosensitive drum 20 to be constant so that a good density can always be obtained regardless of the density of the original. Before starting the off-line copying, the surface potential is first monitored. This is because the light reflected by the standard (white) reflection plate 10 is applied to the surface of the photoconductor drum 20 and is monitored by the surface potential sensor 16 so that it becomes an appropriate value. Control. In the off-line copying operation, when the user selects the auto mode, the optical system performs a pre-read scan for the document monitor, monitors the document density, and sets the corona voltage and bias value.
If this pre-scanning scan operation is troublesome, the density of the original should be monitored while monitoring the document density one after another in real time.
Controls the value of development bias. In the case of continuous copying (making multiple copies from the same original), it is possible to control the corona voltage and the amount of lamp light from the second copy to obtain an appropriate density. In addition, the appropriate density and the size of the original may be detected by sampling the reflected light having the original density applied to the original surface. In this case, the light amount of the exposure lamp 3 is controlled. The offline copying operation has been described above.

Next, online printing will be described with reference to FIGS. 2 and 3A and 3B. Erase Lamp / Write Head 15
Is an LED in which LEDs are arranged in an array as shown in Fig. 3 (a).
The LEDs are arranged at a density of 16 lines / mm, including the array 74. A driver / data transfer circuit (shift register) 73 for the LED is arranged on the substrate so as to be paired with the LED, and the erase lamp / writing head 15 is connected to the short focus lens 75 shown in FIG. When combined, it can be used both as an erase lamp and as a writing head for online image data. That is, the erase lamp / write head 15 is used as an erase lamp for erasing the area other than the image forming area in the off-line copying operation, and is used as the image data write head in the online printing operation. is there.

Next, the control units 62 and 63 of the image forming apparatus 51 will be described. FIG. 4 shows a configuration for controlling the image forming apparatus 51 of the embodiment using four controllers (CPU) 81 to 84. The controllers can communicate with each other via an internal network (eg, μLAN). The controller 81 is the image forming apparatus 51.
The operation sequence control is performed and mainly the mechanical part is controlled. When the sorters 57-60 are connected, the sorter stacker is designated. The controller 82 performs servo control of the optical system and control of the operation panel and display unit. The controller 83 controls the erase lamp / write head 15. The image information input from the readers 53 to 56 is processed by the controller 83 and printed. For example, the image information read by the reader 53 is subjected to appropriate image processing for good reproduction of halftones, and image compression is performed for efficient transfer of image data. Therefore, the controller 83 expands the compressed transfer data, and then writes an image on the surface of the photosensitive drum 20 by the erase lamp / writing head 15 shown in FIG. The controller 84 performs LAN interface with the readers 53 to 56, and is interfaced by the RS232C system as an example here.
Further, the controller 84 also performs the priority processing of the embodiment described later. The controllers 81 to 84 in FIG. 4 are ROM and RAM respectively.
Including 1 chip CPU with built-in
1, NEC's 87AD, etc. are used, but each has an external I / O element and a memory if necessary.

As described above, the controller 81 controls the mechanical portion of the image forming apparatus 51 of the embodiment. Therefore, although not shown, a plurality of I / O elements (ports) are connected to the controller 81, the CPU body of the controller 81 has an A / D converter with eight channels, pattern recognition of the document density, and the temperature of the fixing heater. An input for controlling the light amount of the exposure lamp and an analog signal for detecting the surface potential of the photosensitive drum 20 are input to the A / D converter. In order to advance the timing of the control sequence, the photosensitive drum 20
Is detected and the controller 81 counts this clock pulse and advances the mechanical control sequence. Further, a zero-cross pulse that detects the zero-cross point of the AC input is input, the AC power is switched using this zero-cross pulse, and power control is performed by, for example, phase control of the exposure lamp 3.

The controller 82 controls the original reading scan motor of the image forming apparatus 51 of the embodiment, controls the photosensitive drum 20 and the main motor for driving the conveying system, the pulse motor for moving the zoom lens 11 for changing the zoom ratio, and the operation / display. Performs key input and display control for the section.

The controller 83 controls the erase lamp / write head 15. As described above, in the embodiment, the LED array 7
4 is used as the write head. Also the controller 8
Reference numeral 3 has a 2-line buffer as a buffer memory for input image data. When the resolution is 16 lines / mm, A
Image data for 2 lines of 4 sizes in the main scanning (horizontal) direction is buffered, so 6.4 Kbytes per line, 13 in total
It has K-byte buffer memory.

The controller 84 controls, in part, the interface with the external connection readers 53-56. As shown in the first diagram, a LAN of a relatively small scale is configured via the AC power line. As the RS232C interface 41, an appropriate I / O chip (for example, I / O controller 8255 or 8251) is connected to the CPU.

FIG. 5 is a schematic sectional view of the reader. For example, the reader 53 is a movable document table, and the document table 91 uses a five-phase pulse motor 92 to perform highly accurate scanning. The user sets the original on the original table 91, and sets the number of copies and the scaling factor from the console. Then press the start switch and the pulse motor
92 is rotated, the fluorescent lamp 94 for exposing the original is turned on, and scanning (scanning) is started. Original image is short focus lens 93
An image is formed on the image sensor 95 of the same size. The formed image is electrically converted, temporarily stored in the line memory 96 as pixel data, and transmitted to the image forming apparatus 51 via the RS232C interface 41. Note that the enlargement / reduction of the image based on the scaling factor is performed by a logical process. Image processing for halftone reproduction is performed and appropriate data compression is performed before transmission to the image forming apparatus 51. Image forming device 51
Then, after decompressing the compressed data, writing is started. In this case, since the memory is still expensive at present, if the reader 53 has no page memory, scanning is performed by the number of copies set by the user.

FIG. 6 is a flow chart showing the priority control of the embodiment. In this example, the offline copying operation of the image forming apparatus 51 has the highest priority, followed by the reader 53, the reader 54, the reader 55, and the reader 56. Figure 6 shows readers 53-56
An example in which an offline copy request is issued from the image forming apparatus 51 during execution of the online print of FIG. In step S61, the occurrence of an offline interrupt is checked, and if there is an interrupt request, the process proceeds to step S62. In step S62, it is checked whether or not the online printing operation is in progress. If the online printing operation is in progress, the process proceeds to step S63 to display a weight on the image forming apparatus 51. At step S64, the completion of one cycle of the online print is waited. Eventually, when one cycle of online printing is completed, the process proceeds to step S65 and the reader 5
Generates a wait signal at 3 to 56. The signal is an image forming device 5
It is a busy signal of 1. During this time, no reader can send an image signal and is waiting. At step S66, the weight of the image forming apparatus 51 is released. At step S67, one offline copy is executed. At step S68, the completion of the offline copy is waited. When the off-line copy is completed, the process advances to step S69 to release the wait signal to the reader. At this point, an online print request from the reader is accepted, and online printing is started by a processing routine (not shown). If the priority is satisfied with the other readers, printing of the next sheet of the reader interrupted in step S65 is resumed. On the other hand, when the image forming apparatus 51 is requested to continuously copy a plurality of sheets of the same original document, after exiting the flow of FIG. 6, the ENTRY is input again. However, at this point in time, the request for online printing has already been received, so the offline copy has to wait for one time.

In this way, for example, when the image forming apparatus 51 makes a request for offline copy during online printing from the reader 53, all the operation requests for either online printing or offline copying are satisfied (for example, the total number of copies is Until the end), (a) the operation of low priority online printing is interrupted at the end of one predetermined process (paper discharge process), and (b) the high priority offline copy operation is performed. A predetermined one step (copy for one sheet) is executed, (c) Next, a predetermined one step (print for one sheet) of low priority online printing is executed, and the procedure returns to (b). However, the priority control process is continued.

FIG. 7 is a diagram showing an example of the configuration of another embodiment system using a power line (power line). In this way, the local area LAN can be configured easily by using the power line modem.
The connection device is not limited to the reader, and a personal computer PC and word processor WP are also connected. If you want a hard copy, either the image forming device (workstation) or the (image) printer is available. It may be output, or the printer may be designated because each device is addressed.
In addition to taking a hard copy to the system, the image read by the reader is used (in this case, a magnetic disk,
A file server for saving to optical disk, floppy disk, etc.) is prepared. In this way, each user can manage their own area by ID number,
You can secure your own confidential area. No other person can disclose the confidential information unless they know the ID number. Also, a public area that can be used by anyone may be provided in this area to be used as an electronic bulletin board.

Details are omitted.

Next, let us describe the spread spectrum (SS) communication method proposed as a power line modem. Conventionally, AM, FM and PM modulation methods have been considered as information transmission methods using such power lines. However, due to the special circumstances of the power line, it has been difficult to perform stable transmission with each of the above modulation methods. A spread spectrum (SS) communication system is a modulation system that is resistant to such variations in transmission characteristics. The SS communication system spreads the spectrum in a wide band by multiply-modulating the narrow band information signal with a sequence having a high clock frequency, and demodulates the received signal by performing correlation detection and spectrum despreading on the received signal. It is a method to obtain high reception S / N even under the peak power limit. The application to a system using a wired transmission medium such as an optical fiber and a coaxial cable has been examined with a focus on multiple access by code multiplexing because the line characteristics are better than those of a wireless line. However, since the power line has a bad transmission environment, applying the SS method can be expected to greatly improve the characteristics. To briefly describe the principle,
The basic configuration of the modulator / demodulator is as shown in FIG. On the transmitting side, narrowband information data is product-modulated with a PN sequence and sent out to a transmission line, and on the receiving side, correlation detection is performed using the same PN sequence as on the transmitting side to obtain received information data. Since the narrowband information data is product-modulated by the high-speed PN sequence, the modulation signal spectrum is spread over a wide band according to the clock frequency and the cycle length N of the PN sequence as shown in FIG. Get lower. However, this spectrum example shows only the main rope when it is modulated by a rectangular wave PN sequence. Information of narrow band transmission data is uniformly spread in each spectrum component of the modulated signal of FIG. 9 (b). By performing correlation detection on the receiving side, the signals of the respective spectrum components in FIG. 9B are voltage-added, and narrowband information data is obtained. Due to the uniform diffusion of information shown above, for example, even if there is a transmission zero point as shown in FIG. 9 (c) in the transmission characteristic of the power line and the signal component of that portion is lost, the demodulated information data is The signal power lost is only 1 / N. This transmission zero point has the same effect at any frequency position, and as a result, the SS communication method is a method that is resistant to fluctuations in transmission line characteristics.

In addition, since the SS communication system can modulate both analog and digital signals, for example, the voice information of the intercom can be modulated as an analog signal.

Figure 10 shows a functional block diagram of the SS power line modem.
The signal spectrum-spread by the SS modulator is band-limited to the desired band (10HZ to 450KHZ) by the bandpass filter BPF, passes through the driver, and is coupled to the power line through the isolation transformer. Also, on the receiving side,
Separation of 0V commercial power signal (50HZ or 60HZ) and high frequency modulation signal, isolation transformer, amplifier, bandpass filter BP
Input to SS demodulator via F. Here, the bandpass filter BPF on the receiving side may extract a signal in an appropriate band from the viewpoint of the noise characteristics due to the information uniform diffusion of the SS modulation signal. The above-described power line modem may be provided in the power line plug in the premises and connected to the OA device via the RS232C, or the modem may be built in the OA device in advance.

[Effects] As described above, according to the present invention, an image forming apparatus that performs offline print output of an image generated by its own device and online print output of an image generated by another device that is received via a power supply line is output. It can be provided and can easily be connected online with various other devices in various places through a power line, and an image generated by the connected other device can be easily printed out. Further, since the communication between the own device and the other device is performed by the spread spectrum modulation method, there is an effect that stable transmission is realized even through a power supply line having poor transmission characteristics.

[Brief description of drawings]

FIG. 1 is a block diagram of an OA system including an analog / digital image forming apparatus 51 of the embodiment, and FIG. 2 is an optical system of the analog / digital image forming apparatus 51.
FIG. 3A is a front view of the erase lamp / write head 15, FIG. 3B is a layout view of the erase lamp / write head 15, and FIG. Connection diagram of each controller (CPU) of the analog / digital image forming apparatus 51, FIG. 5 is a schematic sectional view of the reader, FIG. 6 is a flow chart showing priority control of the embodiment, and FIG. 7 is a power line. FIG. 8 is a diagram showing a configuration example of another embodiment system, FIG. 8 is a diagram showing a principle configuration of a direct spread SS communication system, and FIG. 9 (a) is a diagram showing an example of a spectrum of information data, FIG. 9B is a diagram showing an example of a spectrum of an SS modulated signal, FIG. 9C is a diagram showing an example of characteristics of a power line, FIG. 9D is a diagram showing an example of spectrum after passing through a transmission line, FIG. 10 is a functional block diagram of the SS power line modem. In the figure, 51 ... Analog / digital image forming apparatus, 53 to 56
...... Digital image reading device (reader), 57-60 ... sorter (sorter / colator), 41 ... RS232C interface, 100 ... SS power line modem.

Claims (6)

[Claims] 1. An image forming apparatus comprising: an online output unit for receiving and printing out first image information generated by another device; and an offline output unit for printing out second image information generated by the own device. In the apparatus, the online output means includes a separation means for separating a modulation signal obtained by spread spectrum modulating the first image information from a power supply line, and a spectrum despreading for demodulation of the modulation signal separated by the separation means. An image forming apparatus comprising: a demodulation unit for controlling the first image information and a print control unit for controlling the first image information to be printed out based on the signal demodulated by the demodulation unit. 2. A deciding means for deciding an execution priority order of an offline output request and one or more online output requests, and the offline output means and the online output means based on the order decided by the deciding means. The image forming apparatus according to claim 1, further comprising a priority control unit that controls 3. The determining means gives the offline output request the highest priority.
The image forming apparatus according to item. 4. The priority control means outputs the low-rank output when a high-rank output request is made while low-rank output is being executed based on the rank decided by the deciding means. The high order output is interrupted at the end of the predetermined one step and the high order output is executed by the predetermined one step, and thereafter, the low order output and the high order output are executed by the predetermined step until either one of them ends. The image forming apparatus according to claim 2 or 3, wherein the off-line output means and the on-line output means are controlled so as to be alternately executed step by step. 5. The image forming apparatus according to claim 1, further comprising a plurality of sorters used corresponding to the first image information generated in each of the plurality of other apparatuses. . 6. The apparatus according to claim 1, further comprising a single sorter having a plurality of stackers used corresponding to the first image information generated by each of the plurality of other devices. The image forming apparatus according to item.