JPS6231866A - Copying device - Google Patents

Abstract

PURPOSE:To eliminate a copying loss and to shorten the copying time of a both side original by discriminating whether or not the original is a blank paper original and controlling to convey and discharge the copying process and the copying paper. CONSTITUTION:The density of an original 19 of an automatic original conveying device 300 is detected by the photodetecting element as the density detecting means, compared with the density of the blank original stored at the memory device in the control device, the original is discriminated to be the blank paper original, and then, the copying process including the exposure through the control device is not executed. Simultaneously, the control device controls to supply the copying paper, when the first surface of the original is the blank, the copying paper is conveyed to a paper resuplying tray 26, and when the second surface of the original is the blank, the copying paper is discharged. By such constitution, the copying loss is eliminated and the copying time of the both side original can be shortened.

Description

[Detailed description of the invention] 1 Sorrow! BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying apparatus, and more particularly, to a copying apparatus that includes at least a document conveying device for conveying a document to an exposure position, and has double-sided copying means for copying onto the screen of a copy sheet.

In order to eliminate the trouble of setting originals randomly on a tree, a copying machine is equipped with a document feeder (hereinafter referred to as DF) that conveys the original to the exposure position, or an automatic document feeder mechanism (hereinafter referred to as A) is installed on this DF. Copying apparatuses equipped with an automatic document feeder (hereinafter referred to as ADF) in series are used.

On the other hand, regardless of the presence or absence of these DFs and ADFs, copying machines that can automatically make double-sided copies are also used for the purpose of saving copy paper, improving the appearance of copies, and eliminating the hassle of copy paper processing. There is.

By the way, a copying machine equipped with a DF or ADF and a double-sided copying function is known, but with this copying machine,
When trying to copy a plurality of double-sided originals at once, a problem has been pointed out that causes copy loss. In other words, there is a high possibility that multiple double-sided originals include a blank original with nothing written on one side, and in the past, the normal copying process was performed even on this blank original. ing.

The present invention attempts to solve the above-mentioned problem, that is, the problem of copy loss in this type of copying apparatus.

As a means for solving the above-mentioned problems, the present invention provides at least a document feed device for conveying the document to an exposure position, and a double-sided copying sheet capable of copying on the screen of copy paper. In a copying apparatus having a copying means, a density detection means detects the density of the original from the start of transport of the original to the start of exposure for copying the original, and the density detected by the density detection means Blank page discrimination means for determining whether the document is a blank document without any information based on the data; and if the blank page discrimination means determines that the document is a blank document, if it is the first page of the document; The fed copy paper is stored in the paper re-feed tray, which is a component of the above-mentioned double-sided copying means, without performing a copying process, while when it is the second side of the original, the first side of the original is copied. The basic feature is that the apparatus includes a control means for controlling the copy sheets stored in the paper re-feed tray to be ejected from the apparatus through the paper passage without performing a copying process.

- In the above configuration, when the blank paper determining means determines that the original is a blank original, the control means prohibits the copying process from operating and, if the original is the first side, sends the copy paper to the re-feeding tray. If it is the second side, the copy paper is ejected out of the copying apparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to embodiments shown in the accompanying drawings.

First, with reference to FIG. 1, the configuration and operation of a copying machine that can operate in an operation mode linked to an automatic document feeder will be schematically explained.

A photosensitive drum (1) is supported at approximately the center of the upper part of the copying machine main body (100) so as to be rotatable in the counterclockwise direction in the figure.
Around it, an eraser lamp (2), a charger (3), a developing device (4), a transfer charger (5), a separation charger (6), and a cleaning device (7) are arranged in order. The photoreceptor drum (1) has a photoreceptor layer provided on its surface, and this photoreceptor is connected to the eraser lamp (2).
It is sensitized and charged by passing through the charger (3) and receives imaging exposure from the scanning optical system (10) to form an electrostatic latent image on its surface.

The scanning optical system (10) is installed so that the document image can be scanned below the lath (11), and includes an exposure lamp (12), movable mirrors (13), (14), (15), and a projection system. It is composed of a lens (16) and a mirror (17). The exposure lamp (12) and movable mirror (13) are set at (v/n) (where n: copy The movable mirrors (14) and (15) move to the left at a speed of (magnification).
It is driven by a motor (not shown) to move to the left in the figure at a speed of (v/2n).

Copy paper is automatically fed 8! from the first paper feed tray (24) or the second paper feed tray (25) loaded at the bottom of the copying machine main body (100). The paper is fed to the copying section by the mechanisms (20) and (22). Upper paper feed roller (21) or lower paper feed roller (2
The copy paper pulled out by intermediate roller (3)
0), and when its leading edge is detected by the paper detection sensor, it is temporarily stopped at the timing roller (31). Then, when the scanning optical system (10) turns on a Lenost switch (not shown), the copy paper is transferred to the photoreceptor drum (10).
) is sent to the transfer section in synchronization with the image formed on the toner drum, receives the transfer of the toner image by the transfer charger (5), is separated from the surface of the photoreceptor drum (1) by the separation charger (6), and is transferred to the conveyor belt. ) (32) to the fixing device (3
3), the image is fixed by a heat roller, and the paper is discharged onto a paper discharge tray (35) via a discharge roller (34). After the transfer, the photosensitive drum (1) is cleaned of residual toner and electric charge by a cleaning device (7) or the like, and is ready for the next copying process.

In this basic copying process, when performing double-sided copying on copy paper, the copy paper that has advanced from the fixing device ff1 (33) to the idle roller (36) is moved to the ejection switching lever (501) operated by the solenoid (501). 502), the leading end of the paper is deflected downward, passes through an inverted S-shaped paper path (530), and is stored in the paper refeed tray (26). Paper path (5
30) and enters this paper refeed tray, the passage of the copy paper is detected by a paper sensor (581).

As shown in FIG. 2, the paper re-feed tray (26) has a rectangular shape that is long in the direction (X) of copy paper entry, and the copy paper that enters is separated by a partition plate (593) according to its size.

(594) and (595). The pair of dividing plates (593) and (594) regulate the longitudinal direction of the copy paper, and the dividing plate (595) regulates the width direction. As described below, when copy paper is selected and duplex copy mode is selected, these restraint plates automatically move according to the selected paper size (paper size) to fit the paper size. stopped in position. That is, when the double-sided copy mode is selected, the partition plate (
593) and (594) move to the right in the figure along guide rods (583) and (584) fixed to the bottom of the tray, respectively, and the diaphragm plate (593) turns on the 17-mit switch (572). Then, it is reversed, moved to a predetermined paper position, and stopped. Similarly, the diaphragm plate (595) moves upward in FIG. 2(b) along the guide rod (585) fixed to the bottom of the tray, and when the limit switch (573) is turned on, it is reversed and moved to a predetermined position. It moves to the paper width position and stops there. Note that the actuation plate (59) provided in the gA section of the paper refeed tray (26)
6), when the copy paper enters the tray (26), the solenoid (505) is operated one shot and functions to align the width direction of the copy paper.

Moreover, the paper size, which is the basis for controlling the movement of the above-mentioned partition plates (593) to (595), is coded in advance,
For example, as shown in FIG. 3, a 3-bit binary code is assigned. Regarding this paper size, as shown in FIG.
- (553), (554) - (556) are provided, and the paper size code is automatically set in this copying machine when a predetermined paper feed tray is loaded.

When performing copy processing on the back side of the copy paper stored in the paper refeed tray (26) with the image forming side facing upward, a tilt/idle (503) is used to move the paper refeed roller (504) up and down.
) urges the paper refeed roller (504) downward, and activates the roller clutch to rotate the roller (504) and feed the copy paper toward the roller pair (2)). The fed copy paper is transferred from the roller pair (27) to the intermediate roller (30).
), and is sent to the copying section via the timing roller (31), where the above-described copying process is executed. The copy paper with images formed on both sides passes through a conveyor belt (32), a fixing device (33), an f-id roller (36), and passes above an ejection switching lever (502) from an ejection roller (34) to a paper ejection tray. (35).

The copying fi (100) also includes means for controlling the original on the original table glass (11) so that the density of the copied image is optimized by automatic exposure. That is, in the projection image formation optical path onto the photoreceptor drum (1) (in the example, at the entrance of the projection lens (16)), a density inspection means for detecting the intensity of the reflected light from the original, such as a 7-inch transistor, etc. is installed. A light-receiving element (60) is provided, and the density of the original is detected by the light-receiving element (60) during scanning performed prior to scanning for a copying operation (hereinafter referred to as preliminary scanning), and is compared with a preset density. The illuminance of the exposure lamp (12) is controlled by the exposure lamp (12). Note that the preset density is determined by scanning a white original (19) placed on the part of the original platen glass (1) other than the original at the time of preliminary scanning, and detecting the density with the light receiving element (60). , the data may be stored in advance in a memory or the like.

On the other hand, on the top surface of the main body of the copying fi (100) is a document conveying device, ie, DF, which conveys the document to the exposure position.

There is an automatic document feeding mechanism A that automatically feeds documents to this DF, and a document reversing mechanism tUt (hereinafter referred to as R An automatic document feeder (300) (including the R section) is installed. When it is detected that this ADF (300) is electrically connected to the main body of the copying machine (100) and installed at a predetermined position, the controls of the ADF (300) and the copying machine (100) are associated with each other. and the operation mode of copy tfi (100) is switched to ADF mode. ADF mode is the print key (71,) (
4) is operated, the copying machine (100) operates the ADF (300) while maintaining a standby state, and the roller motor (301) and conveyor belt motor (300) are operated. 302) to drive the document feed roller (302).
03) and the original transport bell) (304), and the original placed on the original tray (305) is copied 8.
! 1 (100) along the top surface of the document table glass (11), and its tip is a paper feed sensor (
A D F (300) to copy fi (10
The above-mentioned copying operation is started when a start signal is output to ADF (300) from the copying machine (100) when the final scanning movement for the original is completed.
When an operation signal is output, the ADF (300) discharges the original onto the paper discharge tray (306). At this time, if the next document is on the document tray (305), the next document is also conveyed to a predetermined position at the same time as the sheet is ejected. The original is in the original tray (
305) is detected by a document sensor (311).

The basic ADF mode is as described above, but when a double-sided original is set on the original tray (305) and a double-sided original copy mode, which will be described later, is selected, the original reversing mechanism, that is, the R unit is also operated at the same time. That is, the document table glass (1
1) When the upper document is conveyed toward the R unit by the conveyor belt (304), a switching lever (307) that switches between ejecting the document and sending it to the R unit is operated by a solenoid (308). .

The original is sent to the R unit, and a bell) (321) is driven by a motor (320,) for driving the original reversing unit.
), it is turned over and sent to the DF again. A paper sensor (312) detects that a document has been fed into the R unit. Also, the sensor (313)
detects that the original is ejected to the original ejection tray (306).

Figure 2 shows the operation panel of copy fi (100), and (7
1) is the print key, (72) is the copy number display, (8
0) to (89) are numeric keys for setting the number of copies, (90)
is the interrupt key, (91) is the clear/stop key, (9
3) (94) is the up/down key for setting image density,
(92) is Beno (- size selection key, (92a)
- (92d) are display areas of the selected paper size.

Also, between the up/down keys (93) (94) and the copy number display section (72) is a key (95) for copying on both sides of the copy paper, that is, selecting a duplex copy mode.
and a key (97) for selecting a double-sided original mode in which the R unit is operated when the original is a double-sided original.

When the double-sided copy mode selection key (95) is pressed, the display section (95a) lights up to indicate that this mode has been selected. Similarly, the double-sided original mode selection key (97) lights up the display section (97a) indicating that this mode is activated.

The key (99) is the up/down key (93) (94)
This key is used to select an automatic exposure mode in which the image density is automatically adjusted without manual setting of the image density, and (99a) is a display section indicating the selection. When the automatic exposure key (99) is pressed, the light receiving element (60) for document density detection is basically activated. Further, the light receiving element (60) may be activated in connection with a specific operation mode even if the automatic exposure mode is not selected.

As shown in FIG. 5, the copying fi (100) having the above configuration has a first
It is associated with a control device (200) including a microcomputer so that its operation is controlled by U (202). Furthermore, this control device (200)
(300) is also associated with a control device including a microcomputer, as shown in FIG.
The third CP forms the center of control of A D F (300)
By exchanging signals and data with U (203), copy fi (100), A D F
(300) are integrally associated with each other and control is performed.

The 1st ICPU (201) is connected to the numeric keys (80) to (89), the print key (71), or various sensors (581L (5
51) - (556), (572).

(573), a display section (72) that displays the number of copies according to the operation of the numeric keys (80) to (89), light emitting diodes for various displays, etc., and a decoder (207). ) are connected through.

In addition, the first CPU (201) has an output port that is connected to a main motor in order to control the operation of the copying machine.

It is connected to drive circuits (not shown) such as a developing motor, a clutch, a charger, etc., a paper refeed roller clutch (504), a paper refeed roller upper and lower solenoid (503), and a discharge switching solenoid (501). The light receiving element (60) for automatic exposure is the A/D of the first CPU (201).
Connected to the conversion input boat. The analog signal from the light receiving element (60) is converted into a digital signal by an A/D converter built in this CPU, and the digital signal is similarly stored in the built-in storage section.

In addition, the predetermined output power of the first CPU (201)
An IC (208) for output boat expansion is connected to the EX), and as shown in FIG. 5(b), this IC (208)
8) includes stepping motors (542) and (543).
is connected. The stepping motor (542) is
Shikiri board (593) (594) shown in fj112 diagram
The motor (543) moves the restraint plate (595)
move.

The first CPU (201) further has an interrupt signal input/output terminal (INT) and a data input/output terminal (S in).
, (Sout), the second CPU (202)
and the third CPU (20
3) is connected.

The second CPU (202) executes operation control of the scanning optical system (10) of the copying machine (100), and includes a scan motor control circuit (204), a variable magnification lens control circuit (205), and various optical components. Connected to system detection switch, etc.

The third CPU (203) generally receives various input signals and outputs a predetermined control signal to the ADF (300) in accordance with the input signals, but in FIG. ), sensor for detecting document presence/absence (3
11) A sensor for passing the i-document to R (312) and a sensor for detecting the document ejection (31)
3) is input. Through these sensor inputs and communication with the first CPU, the transport belt motor (302), document feeding motor (301), document reversing motor (320), and switching lever (307) are controlled.
One embodiment is shown in which a control signal is output to each solenoid (308). Note that a normal transmission signal (302A) and a reverse rotation signal (302B) which is output when receiving a reversed document in the R unit are output to the conveyance belt motor (302).

The above control device r! ! (200)+, :yotte, copy fi(
100) and AD F (300) are associated with each other and controlled, the procedure will be explained using charts 70- from FIG. 7 onwards.

FIG. 7 shows the first CPU (2) of the copying machine main body (100).
01) is a flowchart comprehensively showing the operation control performed by 01). In the figure, when the power is turned on and a hardware reset is applied to this CPU, the program starts. First, in step (SO), initial settings are performed to put the device system into an initial mode, such as clearing the built-in RAM, clearing various registers, and initializing. Next, in step (Sl), an internal timer built into this CPU and whose setting value was previously set in the initial setting step is started.

The next step (S2) is a copying operation routine for activating each operating element in the copying machine body (100) to execute a copying process, the details of which will be explained with reference to FIG.

Step (S3) is a preliminary scan routine performed to detect the document density in advance for the purpose of automatic exposure control, and its details will be explained with reference to FIG. Note that this routine is basically activated by turning on the automatic exposure selection key (99).

Step (S4) determines whether to set the copy image density using the up/down keys (93) and (94) or in the automatic exposure mode using step (S3), and then sets the exposure data. This is a dimming routine applied to a dimming circuit (not shown), and its details will be explained with reference to diagram PA10.

Step (S5) prepares the copy paper for double-sided copying, that is, passes the copy paper copied on the first side through the inverted S-shaped paper path (530) to the re-feed tray ( 26
) is a double-sided copy preparation routine for making preparations to be accommodated in a double-sided copy, and the details thereof will be explained in FIG.

Step (B6) is a double-sided selection routine in which double-sided copying is to be performed on copy paper, and the original is a double-sided original, and whether or not to perform double-sided copying for this double-sided original is selected and set;
The details are shown in FIG. 12.

Step (S7) is a paper selection routine that selects one of the two types of copy paper loaded in the copying machine main body (100) and inputs its food data.The details are explained in FIG. do.

In the next step (B8), when all the processes of the above subroutine are completed, another CPU, that is, @2C
The P U (202) and the third CPU (203) mutually communicate signals and data. This data communication is performed by the first CPU (201) transmitting an interrupt signal to the other CPUs.

In step (B9), it is determined whether the internal timer started in step (Sl) ends. The internal timer is
The length of time for one routine formed by the loop is accurately measured, and when it ends, a predetermined value is reset and the step (Sl) is performed.
and restart. The time of various timers used in each subroutine is controlled using the VC value of the time of one routine measured by this internal timer. That is, depending on the settings of various software timers, the end of the timer is determined by how many times this one routine is counted.

Details of the copy operation routine 7 are shown in FIGS. 8(a) to 8(e).
0 - Show chart.

Prior to a specific explanation, the meanings of the main flags defined in this flowchart and subsequent 70-charts will be outlined.

First, the preliminary scan start flag is set to "1" when a preliminary scan for detecting the document density can be started.

On the other hand, when the preliminary scan ends and the density data processing is completed, the preliminary scan end flag becomes "1".
”. The double-sided preparation flag is set to "1" when preparing to receive a predetermined double-sided copy sheet or copy paper into the paper refeed tray (26). The pattern flag becomes "1" when the density of the original detected by the density detection means is significant, that is, when there is some description (pattern) on the original.
If there is nothing written in the manuscript, that is, it is a blank manuscript, please enter "0".
”. The copy start flag indicates a state in which a copy operation can be started, and is set to "1" at this time. When the first copy flag becomes "1", the first paper feed tray (24)
Or, it indicates that the copying process is ready to be performed on a double-sided copy sheet fed from the second paper feed tray (25). On the other hand, the second hubby flag is "1"
This indicates that the copying process can be performed on the copying paper fed from the paper refeeding tray (26).

When the paper passing 7 lug is set to "1", the operation is merely to convey copy paper or copy paper through a predetermined paper passing path without performing an actual copying operation. When it is "0", it indicates that copy paper or copy paper conveyance control according to normal copying operation is possible.

, = 1-1: □ Dizu QF'AI-I + - 4 wisdom, s-1"
+14-1...ko)...-Tsu-vg,,-/□◆()1
In block (B1), which is a step group consisting of one match, when the ON edge of the print switch (SW), that is, the print key (71) is determined, the preliminary scan start flag is set to "1" if the ADF is not used. If using ADF, ADF) tray or document tray (305)
The sensor (311) determines whether there is a document in the
If so, for the third CPU (203) of the ADF,
Send ADF start signal "1". On the other hand, if it is not the ON edge timing of the print SW, the preliminary scan start flag is set to "1" by the original position signal "1" from the ADF side.

Next, in block (B2), it is determined that the preliminary scan end flag has become "11", and then the double-sided type [7 lag has also become "0", that is, the limit plate (593) of the re-feed tray (26) When (594) and (595) complete their movement, the preliminary scan end flag is set to "0" and step (
In S201), it is determined whether the pattern flag is "1". The pattern flag is "1", which means that the original has a pattern such as a character, figure, etc. In this case, this original should be copied, so in step (S202), it is simply copied. Set the start flag to "1". In contrast, the pattern flag is “0”.
”, in step (S203), the copy start flag is set to “1” and the paper passing 7 lag is set to rlJ. In other words, when the pattern flag is rOJ, it indicates that the document whose density has been detected is a blank document without any writing, and based on this, the copy paper is simply placed in the re-feeding tray (26) without executing the copying process. When the paper is to be transported or fed from the paper refeed tray (26), the paper passing 7 lag is set to "1" so that the paper is ejected outside the apparatus, that is, to the ejection tray (35).

In the block (B3), the double-sided selection display section (9
5a) is determined to be ON, and if it is determined that the second copy flag is "0" in step (S204), step (S
In step 205), the first copy flag is set to "1". That is, once the back side copying of the copy paper is completed, the front side copying of the paper is next performed, so the mode is switched to the front side copy mode. Here, the front and back sides of the copy paper are based on the state of the paper accommodated in the paper feed tray (24) or (25). That is, the surface located above the paper feed tray is called the front surface. Therefore, copies are made on the back side of the copy paper fed from the paper feed tray (24) or (25). In step (S206) following step (S205), it is determined whether the paper passing 7 lag is "0". When it is "0", the connection terminal N is shown in FIG. 8(b).

The normal copy operation routine shown in (c) is performed.

On the other hand, when it is "1", f
: A8 Controls only paper conveyance without performing the actual copying operations shown in FIGS. (d) and (e).

In block (B4) of FIG. 8(b), when the copy start flag becomes "1", the main motor, developing motor, charging/transfer charger are turned on, and the exposure lamp is turned on. At the same time, the copy start flag is reset to rOJ on the premise of monocopying,
Set timer A and timer lB.

Next, in step (S211), if it is determined that the second copy flag is "0", if the first paper feed tray (24) is selected, the clutch (
CL), and also turn on the ttS2 paper feed tray (25).
is selected, the clutch of the paper feed roller (23) is turned on. On the other hand, the second
If it is determined that the copy flag is "1", step (
Proceeding to S212), since the mode is front side copy mode, the clutch (
CL) is turned on.

In block (B5), the end of timer A is determined,
When the timing to end is reached, the first or second paper feed roller clutch is turned off.

In block (B6), timer B is set for the time from the start of paper feeding until it reaches the timing roller (31).
At the timing of completion, the scan signal is set to "1" as a scan start command to the scanner.
Make it.

In block (B7), when the scanner turns the registration switch ON and the timing signal becomes "1", the clutch of the timing roller (31) is turned on, and
A timer C, which is set with the time required for copying, is started.

In block (B8), it is determined whether or not this timer C is terminated, and at the timing when the timer C is terminated, the clutch of the timing roller, the electrification charger, and the exposure lamp are deenergized, and the scan signal is set to rOJ.

The process proceeds from the coupling terminal Q to block (B9) in FIG. 8(c). First, the return signal that is output when the scanner reverses is determined. If it is "1", it is then determined whether the multi-copy is completed, and if the multi-copy is not completed, the copy is sent for the next copy operation. Set the start flag to "1".

On the other hand, if it is determined that the multi-floppy copying is completed, it is determined in step (S221) whether the first copy flag is "1". When it is "1", this flag is reset in step (S222), and conversely, in step (S222), this flag is reset.
3) sets the second copy flag to "1". That is, since the front side copy has been completed, the mode is switched to the back side copy mode. When the first copy flag is "0" in the previous step (S221), the developing motor, Turn off the transfer chart. Then, in step (S224), the second
Set the copy flag to "0" and set timer D. Timer D has a discharge roller (3) from the copying section.
4) A sufficient time is set for the trailing edge of the copy paper to be conveyed.

In block (BIO) of FIG. 8(b), it is determined whether or not this timer D has ended, and the main motor is turned off at the timing of the end. Then, in the output step, the results of the processing up to now are output.

FIGS. 8(ci) and 8(e) show the processing when the paper passing 7 lag is "1". That is, in block (Bll), if the copy start flag is determined to be "1", the copy start flag is set to "0", the main motor and timing roller (31) are turned on, and timer A is set.

Then, as in block (B4) above,
Turn on the clutches of the respective selected paper feed rollers.

If the second copy flag is determined to be "1" in step (S231), the clutch of the paper refeed roller is turned on in step (S232).

In block (812), the end of timer A is determined;
When it is finished, in step (S233), the crank of the activated paper feed roller is turned off (and a timer E is set.The timer E records the last paper fed for each paper length. The time is set long enough for the trailing edge to be removed from the paper feed tray.

In FIG. 8(e), at the beginning of block (B13),
The end of this timer E is determined. When the process is completed, it is determined whether or not the number of multi-copy cent sheets has been fed. If the set number of sheets has not been fed, the copy start flag will be set to "
1" to feed the next sheet. When the set number of sheets has been fed, the timing roller is set to ○FFL and the paper passing flag is set to 10'' in step (S241). Next, r
If 51 copy 7 lag is "0", step (S242
), timer D is set. but,"
In the case of "1", the first copy flag is set to "0" in step (S243), and the second copy flag is set to "1" in step (S244) in order to switch to the front side copy mode.

In block (B14), the end of timer D is determined,
At the end timing, the main motor is set to 0FFL, and the above result is output at the output step.

In this manner, in the paper passing mode, basic copying processes such as the developing process and the exposure scanning process are not performed, and only the passing of copy paper or single-sided copy paper is controlled.

FIG. 9 shows a detailed flowchart of the preliminary scan routine.

In the figure, first in step (S301) it is determined whether the preliminary scan start flag is "1".

If it is "1", the step (S302) resets this flag and proceeds to step (S303). In step (S303), a pattern flag indicating whether the document is blank or not is set to "0" indicating that the document is blank. Thereafter, in order to perform a preliminary scan, the exposure lamp (12) is turned on in step (S304), and "1" is given to it so that a scan signal can be transmitted to the second CPU (202). Then, in step (S305), timer AE is started, and in step (S306), initial settings for document density detection are performed. That is, a sampling counter that gives the number of times the density of the original is sampled is cleared, and an original density counter that adds up the density data of the original as digital data is also cleared. The timer AE is a timer for giving a sampling interval. For example, when sampling a document every 1011111, this distance 110ll1 is i! at the moving speed of the scanner.
A value of 1llW- is set.

If it is determined in step (S307) that this timer AE has ended, the sampling counter is incremented by 1 in step (S308). Then, in step (S309), the analog signal from the document density sensor (60) is A/D converted and sent to the first CPU (201).
), and in step (S310), this digital data is integrated into the document density counter. Step (
In S311), it is determined whether a valid image (corresponding to the document length) has been scanned, and if not, the timer A is set again.
Start E.

If it is determined in step S311 that a valid image has been scanned, the process advances to step S313, and the exposure lamp (
12) and turn off the scan signal rOJl:
do. Then, in step (S314), the data stored in the original density counter is divided by the count value of the sampling counter, and this value, that is, the average density of the original, is used as data for exposure. The amount of illumination light from the exposure lamp (12) during copying is determined based on this exposure data.

In step (S315), it is determined whether the value of the sampling counter is "1". That is, before scanning the document area, for example, while illuminating standard white, the currently applied exposure data (data for exposure) is moved to a predefined storage area, which is a save area. (step (S316)), step (
If it is determined that it is not “1” in step S315), step (S315)
317), the exposure data just calculated and the data in the evacuation area are compared, and if they are different, step (S3
In step 18), the contents of the save area are rewritten with this exposure data, and the pattern flag is set to "1". That is, here, if a j density different from other inputs is input even once, it is determined that there is some description in the manuscript, and the pattern 7 lag is set to [1]. If nothing is written on the original, the pattern flag remains at "0" as set in step (S303).

When the above processing is completed, the preliminary scan flag indicating the end of the preliminary scan is set to "1" in step (S319).

Next, details of the light control routine shown in FIG. 10 will be explained.

In block (840), processing is performed when automatic exposure is selected. When the ON edge of the selection key (99) is determined, if the display part (99a) is not lit, it is lit, and if it is lit, tl'? Let it light. When this display section (99a) lights up, the automatic exposure mode is set.

Blocks (841) and (B42) are for manual exposure, and the exposure data is incremented at the ON edge of the key (93), and when it exceeds "9", it is limited to "9". Further, in block (B42), the exposure data is decremented at the ON edge of the key (94), and when it falls below "O", it is returned to "0". In either case of automatic exposure or manual exposure, the exposure data determined therein is given to a dimming circuit (not shown) in step (S401).

FIG. 11 shows details of the double-sided copy preparation routine.

In block (851), first, it is determined whether the double-sided copy selection display section (95a) of the copy paper is lit. , turns on the paper refeed Laurent Lenoid (503). That is, the ejection switching lever (502) is turned downward, the paper refeed roller (504) is retracted upward, and the paper passage path is set so that the copy paper can be carried into the paper refeed tray (26). Then, the paper re-feed tray (26
), the stepping motors (542) and (543) are respectively reversed so as to return each partition plate to its reference position.

In block (1352), limit switch (572)
) is determined, and when the ON edge is determined, the motor (542) is rotated in the normal direction. Then, set the paper length of the selected paper to MW from the maximum vertical length of 420 mm.
The obtained value is set in the A register, and the motor (542) is driven using the value of the A register as a target value.

The motor (542) is turned off when the opposing partition plates (593) and (595) move through the area of the A register.

In block (B53), nine plates (595) are moved in the width direction in the same manner. That is, the limit switch (57
3) Turn the motor (543) forward at the ON edge and set the value obtained by subtracting the vapor width from the maximum width of 297 mm B.
Drive the motor (543) up to the value in the register. Then, in the block (B54), both motors (542),
(543) are both turned OFF, it is assumed that preparation for the duplex copy mode is completed, and the duplex type 4a7 lag is set to "0".

FIG. 12 shows details of a double-sided selection routine for copying both sides of a copy sheet and/or copying each side of a double-sided document.

In block (B81), first, reception of both modes is processed only when copying is not in progress. When the ON edge of the double-sided copy selection key (95) is determined, the display section (
If 95a) is ON, turn it 0FFL, and if it is OFF, turn it ON and light it up. By lighting up this display section (95a), the double-sided copy mode becomes executable. Similarly, in block ([162), double-sided source W4 selection key (97
) controls the lighting of the display section (97a). When the display section (97a) lights up, the machine enters a double-sided original copy mode.

FIGS. 13(a) and 13(b) show details of the paper selection routine.

In the figure, first, it is determined whether copying is in progress, and only when copying is not in progress, the paper selection key (92) is turned on.
I accept Ninno. fifJ1 paper feed or tray (
24) is selected, the first paper feed code is loaded into the CPU, otherwise the second paper feed code, that is, tray (24) is selected, is loaded into the CPU.
5) Read the second paper feed code. Then, based on this code input, the next paper size code conversion routine is executed, and in the next step, one of the display sections (92a) to (92b) corresponding to the selected paper size is turned on.

FIG. 13(b) shows an example of the paper size code conversion routine. For example, the detected size) −
M[2J (binary text "0o10") text is A4 vertical, and this code is converted to the actual paper size. That is, in this case, 297 (
1otIl), set the vapor width to 210 (τ0 resistance) in Nostar.

FIG. 14 shows the third CPU of ADF (300)
(203) is a flowchart comprehensively showing the operation control performed by (203).

First, in step (AO), initial settings are performed.

Next, in step (A1), an internal timer built into this CPU and whose timer time is previously set in initial settings is started. Step (A2) is basically a document controller that automatically positions the document at a predetermined position on the document table glass (11), that is, the exposure position, and automatically ejects the document that has been positioned. - is a routine and will be explained in detail in FIG.

In step (A3), a determination is made as to whether or not the internal timer that was initially set has ended, and each time the internal timer has ended, the process returns to step (A1), and this one routine forming a loop is repeatedly executed. Using the length of time of this one routine, subroutine (A2
) to count the various timers used in the. The timer value determines the end of the timer based on how many times this one routine has been counted. In addition, the copying machine body (10
Data communication with the first CPU (201) of 0) is performed by an interrupt request (INT) from the first CPU (201).
This is performed by an interrupt routine regardless of the progress of this main routine.

No. 15 showing details of the manuscript control routine (A2)
In Figure 1, Step (8201) to (A207)
The document tray (305) is detected by the document sensor (311).
When it is detected that there is a document at the document feed roller (303) and document conveyance bell (304), the document feed roller (303) and document conveyance bell (304) are driven. That is, if it is determined in step (A201) that there is a document in the document tray, it is determined in step (A202) whether the ADF start signal is 11''. When the print key is turned on, this ADF start signal becomes "1" (B 1 in FIG. 8(a)). Step (A
The process proceeds to step 205), where it is determined whether the surface flag is rOJ or not. This front side flag is a mode in which the front side (first side) of the original is copied when it is “0”, and “1
” indicates that the mode is for copying the back side (second side) of the original. If it is determined in step (A205) that the surface flag is "0", step (8206)
Now, we plan to copy the back side of the negative side and set the front side flag to "1". Then, in step (A207), we rotate the conveyor belt motor (302) in the forward direction, and at the same time rotate the document feed motor (3).
01) is turned on. On the other hand, if it is determined that the ADF start signal is rOJ in the above step (A202), it is determined in step (A203) whether the document feed flag is "1", and if it is "1", the document feed flag is once determined in step (A204). This flag is set to "0" and the process proceeds to step (A205).

Next, in step (A208), the first CPU
It is determined whether the double-sided original signal transmitted from (201) is "0". When it is "0", the document feeding processing routine (A20), which is the basic operation of the ADF, is executed. On the other hand, when the value is "1", the document feed reversal processing routine (A30) is executed in order to first copy from the back side of the document using the reversing unit (R). Details of these routines will be explained with reference to FIG. 16 and ttS17, respectively.

In step (A209), it is determined whether scanning for a preset number of copies has been completed. Upon completion, the scan end flag is set to "1" in step (A210). In step (A211), it is determined whether this scan end flag is "1", and if it is "1", the next step (A211) is performed.
In step 212), it is determined whether the double-sided original signal is "0".

If it is "O", that is, it is a single-sided original, step (A21
In 3), the surface flag is set to "0" and the scan end flag is also set to rOJ. Then, in the next step (A40), a document discharge processing routine is executed.

On the other hand, in the above step (A212), the double-sided original signal is "
If it is determined that the flag is not "0", that is, it is "1", the process proceeds to step (^Z14), where it is determined whether the front side flag is "1" or not. Since the state is the same as that of a one-sided original, the process advances to step (A213). On the other hand, when it is "1",
A document reversal processing routine (
A50) is executed. Details of these routines are shown in FIGS. 18 and 19, respectively.

FIG. 16 shows details of the document feeding processing routine.

In this routine, it is determined whether the original is set at a predetermined position on the original table glass (11) by monitoring the time of the timer. That is, when a document is fed and the paper feed sensor (310) is turned on, the ONN edge is detected,
7 Set lag K to "1" and start timer A1. Timer A1 is used to turn off the document feed motor (301) as in steps (A26) to (A27), and is set in advance to a value until the document comes to the position where it receives the drive of the conveyor belt (304). Set. what if,
The document feed motor (301) is turned off by timer A1 monitoring.
If the FF is not activated, even if the document is completely fed, there is a possibility that the document will be fed to the next document, and timer A1 prevents this. Next, step (A23
), when the 7 lag K is "1", the OFF edge of the paper feed sensor (310) comes, that is, when the trailing edge of the document is detected, the 7 lag K is "1".
Set lag K to rOJ and start timer A2.

The timer A2 is set to a value until the trailing edge of the document reaches the document edge localization value of the document platen glass (11). In step (A28), it is determined whether the timer A2 has ended, and when the timer A2 has ended, the conveyor belt motor (302) is turned off. OFF
At the same time, in step (829゛), the first CPU (
200).

The document feed reversal processing routine (A3
0), first, in block (B^31), when the ON edge of the document feed sensor (310) is determined, the reversal switching solenoid (308) is turned on, and at the same time, the reversing motor (320) of the R unit is turned on. . That is,
Switch the switching lever (307) to the R unit side and operate the bell (321). Then, timer D1 is started.

In block (B^32), it is determined whether or not this timer D1 has ended, and when the timer D1 has ended, the document feed motor is turned off. Note that the timer D1 is set to the time until the fed document reaches the position where it is driven by the conveyor belt.

Next, in block (B^33), while the conveyor belt motor is rotating forward, when the document passing sensor (312) turns on, that is, when the leading edge of the document enters the R unit side, the 7 lag K is
1”.

In the block (B^34), first, this 7 lag K is “1
”, and when the OFF edge of the sensor (312) is determined, the 7-lag K is returned to rOJ, and the conveyor belt motor (302) is reversed.

Next, while the conveyor belt motor is reversing, the sensor (31
2) ON edge, that is, when the document is reversed by the R unit and its leading edge comes out, timer D2 is started. The timer D2 is connected to the sensor (312) to the document platen glass (
11) The time required for the document to reach the leading edge position of the document is set.

In block (B^36), the end of this timer D2 is determined. If it has not ended, the process returns to the main routine, but if it is determined that it has ended, the reversal switching solenoid (308), the reversing conveyor belt motor (302), and the R unit reversing motor (320) are activated at that timing.
) to OF FL and sets the original position signal sent to the first CPU (201) to "1".

FIG. 18 shows details of the document discharge processing routine (Δ40). In this routine, a process is executed to eject the original on the original platen glass (11) to the original ejection tray (306). In advance, in step (841), the document tray (3
05), and if there is, the document feed flag is set to "1". If not, step 7 (^
43), the conveyor belt motor (302) is rotated forward and timer B is started. Timer B is preset with a value corresponding to the time required to eject the maximum size original on the original platen glass.

In step (^45), the end of timer B is determined, and the conveyor belt motor (302) is turned off after waiting for timer B to end.
do.

FIG. 19 shows details of the document reversal processing routine (Δ50). In this routine, when the back side of the original has been copied, the R unit is used to turn the original on the original platen glass (11) to the front side, and the original is placed at a predetermined position on the original platen glass again. I do.

That is, in block (BΔ51), scan end 7
If it is determined that the lag is "1", the reversal switching solenoid (308) is turned on and the conveyor belt motor (308) is turned on.
02), turn on the forward rotation and 1 reverse rotation motor (320). In block (13A52), when it is determined that the conveyor belt motor is rotating normally, it is determined that the document sensor (312) is on the ○N edge. When the ON edge of this sensor is determined, that is, when the leading edge of the document enters the R unit, 7lag J is set to "1".

In the block (B^53), after confirming that the 7 lag J is "1", in the next step the sensor (312)
Determine OFF Esso. When the OFF edge, that is, all the way to the rear edge of the document has entered the R unit, 7 lag J
is returned to "0" and the conveyor belt motor is reversed at the same time.

In the next block (BA54), once it is determined that the conveyor belt motor is in reverse rotation, it is then determined whether or not the sensor (312) is turned on. When the original is reversed and comes out of the ON edge, that is, the R unit, timer C is started. Timer〇 has the original as a sensor (312)
The time required for the document to reach the leading edge of the document on the document platen glass (11) is set.

At the beginning of the following block (B^55), the end of this timer 〇 is determined. When the process is completed, the front side copy mode is entered, so the front side flag is set to "0" and the reversal switching solenoid, conveyance belt motor, and reversal motor are turned off. Then, the original position signal to be transmitted to the first CPU (201) is set to "1".

As described above, when it is determined that one side of a double-sided document is blank, if it is the first side of the document, the paper is simply transported to the re-feeding tray, and if it is the second side of the document, the paper is transported to the re-feed tray. , the copying process such as exposure scanning, development, and fixing for copying is omitted by simply discharging the paper from the paper re-feed tray to the output tray.

In the above embodiment, the control mode is shown in which the fed original is first reversed to copy the back side, and then reversed again to copy the front side. Of course, the control may be such that the front side of the sent document is first copied, then it is reversed and the back side is copied.

In addition, in this example, a sensor for self-correction is used as the document density detection means for detecting that the document is blank, but it is of course possible to provide a separate sensor for the purpose of detecting blank pages. You can also do this.

Furthermore, in this embodiment, the density of the document is detected by a preliminary scan, but there is no particular need for a preliminary scan.
For example, it is also possible to install a density sensor in the document feeding path and use this to detect the density and whether or not the paper is blank.

As described in detail above, the present invention is configured so that the copying process is not performed on the blank side of a double-sided original, which eliminates copying loss and contributes to resource and energy conservation. In addition, it is possible to reduce the copying time for double-sided original copying by one hour.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a copying apparatus according to an embodiment of the present invention, and FIG. 2 schematically shows a refeeding tray. FIG. 1A is a longitudinal sectional view, and FIG. It is. Figure 3 is a diagram showing the correspondence between paper sizes and their codes, Figure 4 is a schematic plan view of the fabricated panel, Figures m5 (a) and (b) are schematic circuit diagrams of the control device including the microprocessor, 16 The figures are schematic circuit diagrams showing the input/output relationship of the third CPU, which is the center of control of the ADF.
Figure 10, Figure f511. Figures 12 and 13 (a) and (b) each show the first
A flowchart showing the procedure of operation control performed by the CPU,
FIG. 14, FIG. 15, FIG. 16, FIG. 17, FIG. 18, and FIG. 19 are flowcharts showing the operation control procedure performed by the third CPU of the ADF. 100...Copying machine main body, 26...Refeed tray, 6
0... Light receiving element as concentration detection means, 300...
Automatic document feeder, R...-document reversal unit, 20
1.202,203...Microcomputer.

Claims (1)

[Claims] (1) In a copying machine that is equipped with at least a document transport device that transports a document to an exposure position and has a double-sided copying means that can copy onto the screen of a copy sheet, exposure for copying the document starts from the start of conveyance of the document. a density detection means for detecting the density of the document until the document is read; and a blank page determination device for determining whether or not the document is a blank document without any information based on the density data detected by the density detection means. When the blank page discrimination means determines that the document is blank, if it is the first side of the document, the copying process, which is a constituent element of the double-sided copying means, is performed on the fed copy paper without performing the copying process. While the paper is stored in the paper feed tray, if it is the second side of the original, the first side of the original is copied and the copy paper stored in the paper re-feed tray is passed through the paper path without performing the copying process. What is claimed is: 1. A copying apparatus comprising: a control means for controlling the image to be ejected to the outside of the apparatus through the copying apparatus.