JP2575111B2 - Double-sided recording device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided recording apparatus that copies an image of a document on both sides of a sheet and sorts and stores the copied sheet in a plurality of storage units.

[Prior Art] In a conventional duplex copying machine for copying an original image on both sides of a paper, if a double feed of paper occurs during double-sided copying, an operator interrupts the operation in order to recover the double feed. I was

In such a conventional two-sided copying machine, the operator can copy again the portion that is insufficient due to double feeding.However, in the case of a two-sided copying machine equipped with a document feeder or a sorter, the operator is required to copy the document. The original to be re-copied must be located in the feeder, and the paper that has been copied only on one side due to double feeding is located in the bin of the sorter, and the re-copied paper is placed in that bin. Had to be manually accessed and was very annoying.

[Purpose] The present invention has been made in view of the above-described problems, and has as its object to provide a multi-fed sheet without giving a burden to an operator even if a multi-fed sheet is double-fed during double-sided copying. It is an object of the present invention to provide a double-sided recording device which enables the recovery of an image.

In order to achieve this object, the present invention provides a document feeder for feeding a document to an exposure position and discharging the document after the exposure, and exposing a document sequentially fed to the exposure position by the document feeder. Exposure means, an image of the document exposed by the exposure means is copied onto the surface of the sheet fed from the sheet feeding unit, the sheet is sent to the temporary storage means, and the next document exposed by the exposure means Image recording means for copying the image of the sheet on the back side of the sheet fed from the temporary storage means, and after making the image recording means perform a set number of copies on the front side of the sheet, the temporary storage means Copy control means for causing the image recording means to perform a copy operation on the back surface of the sheet until there are no more stored sheets, and a storage means for sorting and storing the sheets copied by the image recording means into a plurality of storage portions. Counting means for counting the number of sheets on which a copy operation has been performed on the back side of the sheet by the image recording means; and multi-feeding of sheets generated during front side copying or back side copying based on the count result of the counting means. And a double feed detecting means for detecting the double feed of the sheet during the recovery after the double feed detecting means detects the double feed of the sheet until the original corresponding to the surface of the sheet where the double feed has occurred is fed to the exposure position. The document feeding means is made to feed the document idly, and the image recording means is caused to perform the copying operation on the front side of the sheet fed from the sheet feeding section for the set number of copies, and then temporarily stores the original. Recovery control means for causing the image recording means to perform a copying operation on the back surface of the sheet fed from the means.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1-1 is a schematic cross-sectional view of a copying machine to which the present invention can be applied, and the outline of the structure and operation of the embodiment will be described based on this drawing.

The surface of the drum 1 is made of a seamless photoreceptor using a photoconductive layer, is rotatably supported on a shaft, and is driven by a main motor operated by a push button of a copy key (106) shown in FIG. Start rotating.

When the drum 1 is rotated at a predetermined speed and a potential control device (pre-processing) described later is completed, the original placed on the original platen glass 26 is turned on by an illumination lamp integrally formed with the first scanning mirror 22.
Illuminated at 21, the reflected light is scanned by a first scanning mirror 22 and a second scanning mirror 23. First scanning mirror 22 and second scanning mirror
Since the scanning mirror 23 moves at a speed ratio of 1: 0.5, the original is scanned while the optical path length in front of the zoom lens 20 is always kept constant.

The reflected light passes through the zoom lens 20, the third mirror 25, and the fourth mirror 24, and then forms an image at the exposure unit A on the drum 1. The drum 1 is neutralized by a pre-neutralizing means 9 composed of a pre-neutralizing lamp, and then charged by a charger 2 with corona (for example, positive (+) charge). Thereafter, the image irradiated at the exposure section A is subjected to slit exposure. By this slit exposure, an electrostatic latent image having a charge remaining on a black portion of the document is formed. The electrostatic latent image formed on the drum 1 is developed by a developing roller of a developing device 4 and visualized (visualized) as a toner image. The toner image is transferred onto a transfer sheet fed by a transfer charger 5. Transcribed.

 Next, an outline of paper feed control of transfer paper will be described.

The transfer paper in the upper cassette 13 or the lower cassette 14 is fed into the copying machine main body by the paper feed stepping motor 11 or 12, and sent to the photosensitive drum 1 at the correct timing by the register roller 10. The leading edge of the latent image and the leading edge of the paper are made to coincide with each other at the transfer section. Next, the transfer charger 5
While the transfer paper passes between the drum 1 and the
The upper toner image is transferred.

After the end of the transfer, the transfer paper is separated from the drum 1 by the separation neutralizer 6.
Fixing rollers 17, 18
And is fixed by pressurizing and heating, and then discharged out of the copying machine by a discharge roller.

After completion of the fixing, the fixing roller is cleaned by the web 19.

After the transfer, the drum 1 continues to rotate, and a cleaning device 8 composed of a cleaning roller and an elastic blade is provided.
The toner collected after cleaning its surface is collected in a discharge toner container by a pipe (not shown), and proceeds to the next cycle.

Reference numeral 200 denotes a pedestal style having a 2,000-sheet deck which can be separated from the copying machine body 100 and an intermediate toner for double-sided copying.

Reference numeral 46 in the peddy style 200 denotes a lifter of 2,000 sheets, which lifts up according to the amount of paper so that the paper 45 always hits the paper feed roller 44.

At the time of double-sided front copy, the flapper 31 of the main body is raised, the copied paper is guided to the peddy style 200 side, and stored in the intermediate tray 47 through the peddy style conveyance path 40. 49 is a paper size control plate of the intermediate tray, which moves according to the paper size to be stored. The middle tray 47 can store up to 99 sheets. Next, at the time of double-sided back copy, the copy paper is guided to the registration roller 10 of the main body 100 through the path 48 by the feed rollers 41 and 43 and the separation roller 42 from the intermediate toner 47. Reference numeral 300 denotes an automatic document feeder (ADF), 50 is a paper feed tray for setting documents, and 55 is a paper discharge tray. When a copy is started from the book 100, the original is fed by a feed roller 51, guided to a transport belt 54 by a transport roller 53 and a separation roller 52 for preventing double feed, and the original is placed on a predetermined surface of the glass surface 26 of the main body 100. And the copying operation is started. When a series of copying operations on the document is completed, the document is discharged to a discharge tray 55 via a transport belt 54 and a discharge belt 56. While the original is in the paper feed tray 50, the next original is fed simultaneously with the paper discharging operation. This automatic document feeder has a document processor (RD) having a recirculation path and a document reversing device.
F) is fine. 400 is a collating device (sorter) that collates the copies discharged from the main body. Reference numeral 62 denotes a non-sort bin, and since there are only 20 bins in the sort bin 66, the sheets are discharged to the bin 66 when sorting is unnecessary, when there are 21 or more copies from one original, or when the copy is generated by the main body 100. The flapper 64 is a flapper for flowing paper to the next sorter when a plurality of sorters are used.

FIG. 1-2 is a diagram showing the paper path of the copying machine 100 and the duplex unit 200. The transfer paper after the first-side copying has been conveyed along a long paper path from the cassette portion, so that dirt and the like are also attached thereto, and furthermore, the transfer paper has passed through the fixing rollers 17 and 18 and is curled. For this reason, the transfer paper on the intermediate tray 47 is not so good when fed. Therefore, even if the sheet feeding operation is performed by the sheet feeding roller 41, it may not be possible to feed a predetermined amount. Therefore, in this embodiment, a sensor S is provided at the sheet feeding port of the intermediate tray 47 to check whether or not the sheet is reliably fed from the intermediate tray 47. At the time of the first paper feeding, the paper feeding roller 41 is rotated for a predetermined time, and when the transfer paper is not detected by the sensor S, the paper feeding roller 41 is again rotated for a predetermined time. This operation is repeated three times, and a jam occurs only when the transfer paper is not yet detected by the sensor S.

 Next, each part will be described in detail.

FIG. 2 is a block diagram of a control unit of the copying machine shown in FIG. 1-1. In FIG. 2, Q101 is a ROM memory for storing a display, a process, and a program by a command code routine, and a RAM memory for storing various processing data. The main CPU, Q102, is a one-chip microcomputer with built-in I / O ports for input, output and output.
01) One chip micro computer equivalent to
The M memory is a slave CPU that stores programs for controlling the sequence of the copying machine.
Both (Q101) and Slave CPU (Q102) have built-in A / D converters, which are also used for temperature control and adjustment volume input. Q103 to Q106 are expansion I / O ports for expanding input / output of the main CPU (Q101), and are controlled by a data bus and control signals from the main CPU (Q101). Q108
Is a one-chip microcomputer equivalent to the main CPU (Q101), and has an ADF CPU for controlling the automatic document feeder (ADF) 300 and a sorter CPU for controlling the collating device (sorter) 400 shown in FIG. The main CPU (Q101) is connected to each other via a serial communication path (TXD, RXD, SCK), and instructs and controls the feed control of a document and the control of a collating device (sorter) by serial communication.

FIG. 3 is a plan view of the operation unit. In the figure, 102 to 115 are keys, 102 is a numerical key for setting the number of copies, 103 is a clear key for canceling the numerical value, and 104 is a key before the copy of the number set by the numerical keys 102 is completed. An interrupt key for executing another number of copies, 106 is a copy key for instructing a copy start, 105
Is a stop key for stopping the copying operation during the continuous copying of the set number, and 110 is a key for selecting a paper feeding cassette, and the effective paper feeding cassette is sequentially selected from upper, middle, and lower for each push button. Reference numeral 111 denotes a double-sided key for selecting double-sided copying. When this key is pressed, the display 121 of the display unit 101 displays "1" to indicate the first side of double-sided copying. When the copying of the first side is completed, the display 121 automatically displays "2" and instructs the copying of the second side. This display pattern is shown in FIG. At the end of the first-side copy, the number display unit 116 described later
Is displayed as "HO1" as shown in FIG. 4-3, indicating that the current state is the intermediate state. When the ADF is not used, in this state, the operator exchanges the original for the second side and presses the copy key to start the second side copying. In this case, the cassette selection key 110, the numeric key 102, and the double-sided key 111 are not accepted. However, the copy magnification, the copy density, and the like can be changed. When the stop key 105 is pressed in this state, the copy sheet on the intermediate tray 47 is discharged out of the apparatus without executing the second-side copy.

Numeral 115 is a key for changing the magnification mode, which specifies four magnification modes of enlargement, reduction, equal magnification, and continuous magnification. Each time the key is pressed, the magnification mode is changed to equal magnification → reduction → enlargement → continuous → equal magnification. Rotate. FIG. 4-2 shows display examples of the displays 132 and 133 when this key is pressed. During continuous zooming, display 132,
133 is displayed in 134 at a percentage magnification without displaying anything. The magnification is 61-141%, and is indicated by the keys 113 and 112 in 1% units. 114 is the magnification mode selected in 115,
This is a magnification selection key for setting a fixed magnification. I mean
When the reduction mode is set at 115, a fixed reduction ratio is automatically set according to the cassette size selected at that time. For example, if the A4 size vertical feed cassette: A4R is selected, every time the key 114 is pressed, A3 → A4: 71%, B4 → A4: 82
%, A3 → B4: 87%, B4 → B5: 71%, A3 → B5: 61%, A4 → B5: 87%
And so on. As for%, the magnification is always displayed at 134 at the same time as 132,133 is changed. The up / down keys 112 and 113 for continuous zooming are up / down by 1% for each push button of each key, and if the push button is kept pressed for 1 second, the up / down keys are continuously up or down while the push button is pressed. When it becomes 141% or more, it automatically returns to 61% and repeats the operation. When it becomes 61% or less, it becomes 141% and goes down.

The 3-digit numerical display 134 displays 135% in the standard% display for magnification, but it can be switched to various displays by using the display switching switch in the main body for adjustment at the time of maintenance. It is possible. In addition, if the magnification is specified with the down key 112 or 113, and the magnification matches the magnification of the fixed magnification, the fixed magnification display related to the paper size of the selected cassette or the original Can also be displayed. Thus, 134 of the display unit is 3
Although it is a numerical display of digits, normally, the magnification is displayed as a percentage as described above, and "%" of 135 is displayed. However, when the power is turned on, the temperature of the fixing unit is indicated, and "136" of 136 is displayed. In the present embodiment, when the temperature of the fixing unit reaches 170 ° C., the rotation starts at a low speed, and at 180 ° C., the rotation starts at a high speed. However, when the temperature is low, it takes several minutes from when the power is turned on to when the temperature of the fixing device reaches a predetermined temperature, and the operator feels that the waiting time is long. Therefore, the temperature is displayed using the display unit 134 from the power-on to the standby. The temperature of the fixing unit is inputted from the fixing thermistor 210 shown in FIG. 2 to the A / D input terminal of the main CPU (Q101), converted into the temperature, and the display of the display unit 134 is updated every 700 msec. In the standby state, the display 134 automatically returns to the magnification display. The display 134 can be displayed differently by a service person or the like operating the switching switch in the copying machine at the time of factory adjustment or maintenance work.

The set values of the fixing unit temperature adjustment setting volume 206 shown in FIG. 2 can be read directly from the input data from the volume 206 as a temperature setting volume display in the above table. The main CPU (Q101) reads the set value of the volume 206 to change the temperature setting of the fixing device, and at the same time, relatively changes the low-speed and high-speed rotation temperatures at power-on.

124 to 128 are warning displays, all of which are displayed in pictograms. 124
Is displayed on the key counter confirmation display when the key counter for counting the number of copies is not inserted into the socket of the main body. 125 is displayed when there is no cassette in the cassette table selected in the paper / cassette replenishment display, or when there is no paper in the cassette. Reference numeral 126 denotes a developer replenishment display, which is displayed when the amount of the developer in the developing device becomes equal to or less than a predetermined amount. 127 is a paper feed inspection display, which is displayed when paper is jammed in the machine. Reference numeral 128 denotes a discharge toner full display, which is displayed when the used toner is full. Reference numeral 122 denotes a weight display, which is lit when the power switch is turned on and the temperature of the fixing heater is lower than a specified value, and is turned off when the temperature exceeds the specified value and the wait UP process is completed. Reference numeral 123 denotes an interrupt display, which is displayed when the interrupt key 104 is pressed, and is turned off when the interrupt processing is completed. 129 indicates the upper, middle and lower rows of the cassette carried by the cassette selection key 110, and 119 indicates the size of the selected cassette. If the specified magnification and the cassette size do not match at the time of fixed magnification, 119 recommended size blinks. 107 is a selection key for automatic exposure control (AE), and keys 108 and 109 are manual density adjustment keys. When AE is selected, 117 is displayed, the manual density adjustment is ignored, and a clear image without fog on the original is always obtained. In the AE mode, the density adjustment display 11
The result measured at the time of AE scan is displayed in 8 steps in 8 steps.
The keys 108 and 109 are effective when not in the AE mode. When the key 108 is pressed, the bar graph display 118 extends upward, and when the key 109 is pressed, the bar graph display 118 lowers. The standard is shown as a bar graph in the middle. Further, if both the keys 108 and 109 are kept pressed for one second, they are continuously up or down. Reference numeral 116 denotes a three-digit numerical display for displaying the number of copies input from the numerical keys 102. The number of copies that can be set by the numerical keys 102 is 1 to 999. If three or more digits are entered, an overflow occurs and only the last three digits are valid no matter how many digits are entered. That is, if 4 is input after "123", "234" becomes valid and the display becomes "234". When a paper jam (JAM) occurs, a display 131 indicates the paper jam occurrence position to alert the operator. It is displayed in ten bands (J0 to J9), and the paper path from the paper jam occurrence location is displayed. Also, paper feed inspection display
The number 127 is also displayed at the same time, and the number display "P03" indicating the paper jam in the copying machine is displayed on the number display 116 to instruct the operator that three sheets are jammed.

FIG. 5 is a flow chart for repeatedly performing the sheet feeding operation from the intermediate tray according to the present invention. This flowchart is included in the slave CPU Q108, and waits for a tray feed request of F-1 via serial communication from the master CPU Q101 according to the feed timing. When a paper feed request comes from the master, the paper feed roller 41 is turned on for 50 clocks. Here, the clock reference is designed such that one serial communication from the master CPU Q101 corresponds to one clock.
If the sensor S was detected by F-4 and it was not turned on,
If the retry counter is not incremented by 3 in F-5, the flow returns to F-2 again and paper is fed again. F- 3 times
In step 7, the JAM flag is set to notify the JAM to the master CPU, and the entire apparatus stops. If the sensor S is ON in F-4, the sheet feeding has been completed normally, so the sheet feeding completion flag is notified to the master CPU Q101 and the process ends. Thereafter, the master CPU notifies the slave CPU Q102 and the second-side copying on both sides is completed.

In the present embodiment, the refeed operation is performed a fixed number of times, but may be performed for a fixed time.

Further, in this embodiment, a function of detecting a double feed of the transfer paper is provided. When the double feed is detected, the recording operation is temporarily stopped, a predetermined display is displayed to prompt the operator's attention, and the copy key is turned on. As a result, the original is again returned to the original for the first side of the transfer sheet in which the double feed has occurred, and is re-created for the set number.

The double feed detection method according to the present embodiment compares the number of sheets copied on the first side during the second side copy on the both sides with the counter of the number of sheets. If there is paper in the intermediate tray 41 even after the count is completed, it is determined that double feed has occurred during the first-side copy. In both cases, the process ends when the intermediate tray 41 runs out of paper during the second-side copy operation.

When the double feed is detected in this manner, the drive system is normally stopped when the last sheet comes out of the main body, and a check display is output to the number display section 116 of the operation display section of FIG. 3 as shown in FIG. 4-4. Then, the simultaneous buzzer sounds for 2 seconds.

Thereafter, the operator presses the copy key 106 to perform the double feed recovery, and presses the stop key 105 to stop the copy job. When the copy key 106 is pressed, the ADF is used to copy the set number of sheets from the first side of the two-sided document, the operation to return to the previous document is performed, and the first page copy is started when the required document comes to the glass surface. . After the first side copy is completed, the original is automatically replaced and the second side copy is performed.

FIG. 5 is a flowchart for the above control. F
In the case of -1, the process of feeding one sheet from the intermediate tray 41 at the time of the second side of both sides is performed. In F-2, the paper feed counter is incremented by one for each paper feed. In F-3, it is checked by the intermediate tray paper presence sensor S 'whether or not paper remains in the intermediate tray 41. Return to operation. When there is no more paper in the intermediate tray 41, the paper feed counter is compared with the predetermined number of sheets in F-4, and if they match, it is determined that the processing has ended normally (F-5). If they do not match, the multifeed flag is set in F-6, and the number display section 1 is displayed in F-7.
16 is displayed as described above informing that a double feed has occurred.
Thereafter, the main body is stopped, and waits until the copy key 106 (F-8) or the stop key 105 (F-9) is pressed. When the stop key 105 is pressed, the display of the number display section 116 is cleared without performing the double feed recovery in F-10, and the processing ends. Copy key 106
Is pressed, the master CPU is instructed to perform the double feed recovery (F-11), and this routine ends.

In this way, by temporarily stopping the copying operation at the time of detecting the multifeed and displaying a predetermined display to the operator, it is more economical than the apparatus automatically starting the multifeed recovery, and By performing recovery using a copy key, missing information is eliminated.

[Effects] As described above, according to the present invention, the original is copied onto the surface of the sheet fed from the sheet feeding unit, the sheet is sent to the temporary storage unit, and the sheet is fed from the temporary storage unit. Copy the next document to the back of the sheet
In a double-sided recording apparatus that sorts and stores sheets in respective storage sections of storage means, counts the number of sheets that have been copied to the back side of the sheet, and based on the count result, generates sheets generated during front side copying or back side copying. The double feed of the sheet is detected, and at the time of recovery after the detection of the double feed of the sheet, the document corresponding to the surface of the sheet in which the double feed occurs is fed until the document is fed to the exposure position. After the set number of copy operations are performed, the copy operation is performed on the back side of the sheet, so even if it is not possible to detect in which storage unit a single-sided blank sheet generated by double feeding is stored. In addition, double-sided copy sheets for the set number of copies that have been redone are sorted and stored in each storage section, so that all necessary double-sided copy sheets can be reliably stored in each storage section.
Further, according to the present invention, there is no need for the operator to find the original to be re-copied from the original feeding means or to find in which storage unit the single-sided blank sheet has been stored due to double feeding. .

[Brief description of the drawings]

FIG. 1 is a sectional view of a copying apparatus to which the present invention can be applied, FIG. 2 is a block diagram showing a control unit of the copying apparatus shown in FIG. 1, and FIG. 3 is an operation unit of the copying apparatus shown in FIG. FIG. 4-1 is a diagram showing a mode display pattern at the time of duplex copying, FIG. 4-2 is a diagram showing a display pattern at the time of changing magnification, and FIG. 4-3 is a diagram showing an intermediate state display pattern. FIG. 4-4 is a diagram showing a display pattern at the time of double feed detection, and FIG. 5 is a flowchart for explaining an operation for recovery when double feed occurs. 100: Copy machine, 200: Pedestal, 300: ADF, 400: Sorter, Q101 to Q108: Microcomputer.

Continuing on the front page (72) Inventor Shinichi Nakamura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Toshihiko Mori 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Masayuki Hirose 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-60-41054 (JP, A) JP-A-58-187953 (JP, A)

Claims (1)

(57) [Claims] A document feeder for feeding a document to an exposure position and discharging the document after the exposure, an exposure device for exposing a document sequentially fed to the exposure position by the document feeder; The image of the document exposed by the above is copied on the surface of the sheet fed from the sheet feeding unit, the sheet is sent to the temporary storage unit, and the image of the next document exposed by the exposure unit is stored in the temporary storage unit. Image recording means for copying on the back side of the sheet fed from the printer, and after the image recording means performs the set number of copy operations on the sheet surface until the sheets stored in the temporary storage means are exhausted. Copy control means for causing the image recording means to perform a copying operation on the back side of a sheet; storage means for sorting and storing the sheets copied by the image recording means in a plurality of storage portions; Counting means for counting the number of sheets on which copying operation has been performed on the back side of the sheet, and double feed detection for detecting double feeding of sheets generated during front side copying or back side copying based on the count result of the counting means. Means for recovering after the double feed of the sheet is detected by the double feed detecting means, the document corresponding to the surface of the sheet in which the double feed has occurred is fed to the document feeding means until the document is fed to the exposure position. The sheet fed from the temporary storage unit after the document is fed in an idle manner, and after the set number of copies, the image recording unit performs the copying operation on the surface of the sheet fed from the sheet feeding unit. A recovery control means for causing the image recording means to perform a copying operation on the back surface of the recording medium.