JPH01110452A - Picture image forming device - Google Patents

Abstract

PURPOSE:To promote the improvement of usage convenience by cutting fed roll paper, when a document conveying trouble is detected, after detection by a paper detecting means separated by a paper conveying necessary length from a roll paper cut position. CONSTITUTION:When a document conveying trouble is detected by a signal of document detecting sensors PS8-PS11 in an automatic document circulating conveyer 50, paper, fed from roll paper 31 or 32 in a paper feed part 30, is cut by a cutter 41 after a paper detecting sensor PS20, provided separating by a necessary paper conveying length from a position of the cutter 41, detects a point end of the paper. Conveying the cut paper by a timing roller 40 transcribing a toner picture image on a sensitive unit drum 2 by a transcribing charger 7, the paper is discharged onto a paper discharge tray 48 via a fixing device 43 while the copying action thereafter is suspended. In this way, the operator need only process the trouble of a document, and the waste in roll paper is eliminated while usage convenience improves.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image forming apparatus equipped with a document conveyance device, and particularly to a control mechanism for a roll paper for image formation when a document conveyance trouble occurs.

Conventional technology and its problems Conventionally, when a copying machine equipped with a double-width document transport device encounters a problem such as a document jam, it is
As shown in Japanese Patent No. 4-156643, control is performed to stop the document conveyance operation and also stop the copying operation.

However, in such a copying machine, when a trouble occurs in document conveyance, the paper also remains in the copying machine main body at the conveyance position at the time of the trouble. Therefore, the operator has to take out both the yX document and the paper from the apparatus, which is cumbersome.

Means for Solving Problem 1. Accordingly, the image forming apparatus according to the present invention includes: (i) means for detecting document conveyance trouble within the document conveyance device; (i) cutting means for cutting roll paper; i) a paper detecting means provided on a paper transport path a distance necessary for subsequent paper transport from the position where the roll paper is cut by the cutting means; and (iv) a document transport trouble is detected by the detecting means. The present invention is characterized by comprising a control means for cutting and discharging the roll paper fed from the paper feed unit after the paper detection means detects the leading edge of the roll paper.

In the above-described configuration, if a problem such as a document jam occurs in the document conveyance device, the roll paper that has already been fed from the paper feed section will be cut after the paper detection means detects the leading edge of the roll paper. , it will be completely discharged. Specifically, the paper detecting means is installed at a position away from the roll paper cutting position by the cutting means by a length necessary for subsequent paper transport (a length equal to or longer than the interval between transport rollers, etc.). Therefore, for example, if the leading edge of the roll paper has not yet reached the paper detection means when a problem occurs, the roll paper is cut when the leading edge of the roll paper reaches the paper detection means.

Furthermore, if the leading edge of the roll paper has already reached the paper detection means when the trouble occurs, it is cut at the time when the trouble occurs. In this way, the cut paper can be discharged outside the apparatus without any problem.

Embodiment Hereinafter, an embodiment of an image forming apparatus according to the present invention will be described with reference to the accompanying drawings. This embodiment includes a toner image transfer type copying machine main body (1) and an automatic document circulation conveyance device (hereinafter referred to as RADF) that automatically circulates documents by the number of copies.
It is composed of (50).

[Copying machine main body] In Fig. 1, the copying machine main body (1) has a photosensitive drum (2) installed approximately in the center so as to be rotatably driven in the direction of arrow (a), and a main eraser lamp ( 3), electrification charger (4), inter-image eraser lamp (5), magnetic brush type developing device (6), transfer charger (7), paper separation mechanism 8), separation claw (9), blade type developing device A cleaning device (10) is arranged.

The optical system (20) includes an exposure lamp (21) and a mirror (22).
).

(23), (24), lens (25), mirror (26)
), the image of the document being conveyed on the document slit glass (27) is formed on the photoreceptor drum (2) by the RADF (50) described below.Lens (25)
, the mirror (26) is operated by a motor (M2) according to the copying magnification.
can be moved in the optical axis direction.

For each copy, the photosensitive drum (2) has its residual charge erased by a main eraser lamp (3), is given a predetermined charge by a charging charger (4), and is used to erase the original image by an optical system (20). is imaged to form an electrostatic latent image. This electrostatic latent image is turned into a toner image by a developing device (6>).

On the other hand, the paper feed section consists of a main paper feed section (30) that can selectively load roll paper <31) (33), a sketch paper section (32), and a manual paper feed section (34) for cut paper. The configuration is complete.

The roll paper (31), (33) is the roller (35), (
A pair of paper feed rollers (37), <38) via
The paper is pulled out from the paper, guided by various guide plates, fed to a pair of timing rollers (40), and then temporarily put on standby. Also, the cut paper inserted from the manual paper feed section (34) is passed through a pair of paper feed rollers (39) to a timing roller (40).
The paper is fed until then and waits for -10 minutes. Timing roller (40
) is rotated by a predetermined timing signal, and the toner image is transferred to the paper by the discharge of the transfer charger (7>), and the photoreceptor drum (2) is transferred by the AC discharge by the separation charger (8) and the separation claw (9). ) is separated from

The timing signal is issued at the timing when the leading edge of the image formed on the photosensitive drum (2) and the leading edge of the paper are synchronized in the transfer section. Also, roll paper <31).

(33> is cut into a horizontal size or a vertical size by a cutter (41>) based on a cut signal described in detail below. After transfer, the paper is transferred to a conveyor belt (42) equipped with an air suction means (not shown). through the fixing device <43)
The toner is fed therein, where the toner is fixed, and then discharged to the outside of the main body (1) by the first discharge roller (44).

Further, the paper is conveyed vertically upward by belts (45) and (46), and is discharged onto a paper discharge tray (48) by a second discharge roller (47).

The photosensitive drum (2), paper feeding system, and Wi feed system can be driven by the main motor (Ml).

The top picture paper part (30) and the bottom picture paper part (32> each have three sets of microswitches (SWI) to (SW3),
(SW4) to (SW6) are installed. These switches are turned on and off by protrusions provided for each width size when the roll paper is set, and depending on the on/off combination, the roll paper ( 31) and (33), and also detects the presence or absence of roll paper.

The following [Table 1] shows the switch (S comfort) of the upper picture paper part <30)
This [Table 1] shows an example of the code by ~(SW3)
In this case, the on state of the switch is represented as "0", and the off state is represented as "1", and when all the switches are off, it means that the roll paper is not set in the overprint paper section (30).

In addition, the switches (SW4) to (SW
6) also performs similar detection.

[Margin below] [Table 1] Various sensors are installed inside the copying machine body (1). The sensors (Psi) and (PS2) are for detecting cut paper inserted into the manual paper feed section (34).

Sensors (PS3) and (PS4) are connected to the upper and lower paper feed sections (30
), (32) loaded roll paper (31), (3
3). The sensor (PS5) is located just before the timing roller (40), and the sensor (PS6)
, (PS7) are discharge rollers (44), (4
Immediately after 7>, the first passing of the paper is detected. These sensors are also used to detect paper jams and to control other operations of the copying machine main body (1).

Furthermore, the sensor (PS20) is for detecting the fed roll paper, and can be installed at a long distance away from the position where the roll paper is cut by the cutter (41), which is necessary for the subsequent paper transport, and is explained below. It is used to control the cutting and ejection of fed roll paper when a problem such as a paper jam occurs during document transport.

[Automatic document circulation feeder (RADF)] In FIG. 1, the RADF (50) includes a document table (51), document conveyance rollers (52) to (57), document ejection tray (60), and document conveyance motor (M3). ).

Each of the transport rollers (52) to (57) includes driven rollers (52a), (53a), and (53b) to (57a), and guide members for transporting the original are appropriately installed around them. . In addition, conveyance rollers (54), (5
5) is a switching claw (61) for switching the circulation conveyance path.
, (63) and guide plates (62), (64), and the conveyance roller (53>) is provided with a switching claw (65) and a guide plate (66) for switching between circulating and discharging the document.

That is, when the switching claw (61) is also entered with the switching claw (65) entered into the conveyance path, the document is circulated and conveyed between the transport rollers (53) and <54),
63), the conveyance rollers (53) and (55)
When the switching claws (61) and (63) are retracted, the transfer rollers (53) and (56) circulate.

On the other hand, when the switching claw (65) is retracted from the conveyance path, the original is transferred from the conveyance roller (57) to the ejection tray (60).
is discharged to the top.

Each of the above conveyance rollers (52) to (57) is rotationally driven by a document conveyance motor (M3), and the conveyance speed is set at the same time as (V
), the copying magnification (n) is controlled to (V/n). The conveyance speed (V) at the time of notification is the same as that of the photoreceptor drum (
2) is equal to the peripheral speed and paper conveyance speed.

In addition, each sensor (PS8) to (PSI) is installed in the document transport path.
I) is installed. The sensor (PS8) detects the inserted document, and the sensor (PS9) detects the optical system (20).
The sensor (PSIO) detects the document immediately before the light irradiation position by the exposure lamp (21), the sensor (PSIO) detects the document at the circulation/ejection switching section, and the sensor (PSII) detects the document that can be completely ejected. Sensor (PS8) ~ (PSl
In combination with a timer, l) can detect even paper jams in originals.

Next, to briefly explain its operation, the document table (51
) When the sensor (PS8') detects the leading edge of the document inserted from the
2) to (57) are rotationally driven at a peripheral speed corresponding to a preselected copying magnification. Here, the manuscript is RAD F (
50) and passes over the glass (27) to receive light irradiation from the exposure lamp (21), and the reflected light is imaged on the photoreceptor drum (2). At the same time, the length of the document is detected by a combination of various sensors and timers, and switching claws (61) and (63) are selected depending on the document length.
) operates, and the document passes through the shortest circulation path. When the leading edge of the document is detected by the sensor (PSIO), it is determined whether or not copying has been completed. If the circulation for the number of copies has not been completed yet, the switching claw (65) is operated to move the document to the conveyance roller ( 53) to circulate. When the circulation for the number of copies is completed, the original is directly ejected onto the ejection tray (60) through the transport roller (57), and the trailing edge is detected by the sensor (PS).
When detected in II), the motor (M3) stops.

[Operation Panel] In Fig. 2, the operation panel has the following keys,
Display means etc. are installed. Each key has an internal switch that is turned on by pressing it.

(100) is a stop key for stopping the original transport operation of RADF (50), (101) to (110) are numeric keys for setting the number of copies, etc., (111)
is a clear key that functions as a stop key to cancel multi-copying midway, and a clear key to clear the set numbers.
stop key. (112) is an interrupt key for executing interrupt copying, <113) and (114> are magnification up and down keys that increase and decrease the copy magnification in steps, (115) and (116) are exposure amounts. Exposure Up key and Exposure Down key to increase or decrease in steps, (117) is the select key for the main paper feed section (30) or sketch paper section (32), and (118) is the enlargement key.

The copy magnification select key is preset to 2 steps of normal magnification and reduction. (119) is the zoom magnification select key for selecting two types of zoom magnification that are arbitrarily preset by the user. (120) is the zoom magnification (121) is a synchronized cut designation key for cutting the roll paper in synchronization with the length of the document.

The operation panel further includes a display section (140) including a display LED and a fluorescent display tube, which will be described below.

(122) and (123) are LEDs that indicate that the roll paper loaded in the main paper feed section (30) and the sketch paper section (32) has been selected;
7) Rotate each time the on operation is performed.

(132) and (133) are roll paper width size display sections, which are displayed based on signals from the switches (SWI) to (SW6) provided in each paper feed section (30) and (32). (124) to (127) are copy magnification selection display LEDs, which are rotated each time the copy magnification selection key (11g> is turned on). <128
) and (129) are zoom magnification selection display LEDs, which are rotated each time the zoom magnification selection key (119) is turned on. (130), (131)
is a synchro cut selection display LED for the upper and lower roll paper, and 1 of the synchro cut designation key (121)
Rotates every time the switch is turned on.

In the display section (140) using a fluorescent display tube, (141
) is a two-digit display segment that displays the number of copies, etc.

(142) is a 4-digit display segment that displays the selected copy magnification. (143) is a pictorial display instructing a serviceman call. (144) is a step display of exposure amount.

(145) indicates toner empty. (146) indicates roll paper empty. (147) is a paper jam warning display.

(148> is displayed during interrupt copying. (149) is temperature control,
Weight display when moving the lens (25), etc.

[Control Circuit] Figure 3 shows a microprocessor (hereinafter referred to as CPU) (201) that controls the main body of the copying machine (1), and the RA
C controls the DF (50) and optical system (20)
The input/output configuration of PU (215) is shown.

The CPU (201) is an input/output expansion integrated circuit (hereinafter referred to as I
(denoted as C) (202) to (204), (206)
~(208>).IC(202)~(204
) is used as an input IC, and CPU (2
01) via a data line via a decoder (205). Various keys, switches, sensors, etc. are connected to the input terminal. IC(206)~(208)
is no longer used as an output IC, and the control board is connected to the CPU (201) via the decoder (210).

In addition to various parts, the output terminal includes a fluorescent display tube display section (140) and LEDs (122) to (131).
is connected to the LED matrix (209) consisting of C
Each is controlled by a PU (201) via a decoder (211). Random access memory (hereinafter referred to as RAM) (212) is the CPU (201)
The memory is backed up by a battery.

Further, the CPU (201) transmits a value selected from among the nine-step exposure values to the light control circuit (213) as data.

°On the other hand, the input/output port of CPU (215) is RAD
A motor (M2) that moves the feed roll circuit (216), lens (25), and mirror (26) of the document transport motor (M3) of F (50) according to the selected copy magnification.
) is connected to the control circuit (217). In addition, each sensor (PS8) ~ (
The on/off signal from PSII) can be input completely, and the switching claw (61).

(63), turns on the solenoid that drives (65),
An off signal is output. Furthermore, CPU (215)
is connected to the CPU (201) for communication via a bus (214).

[Control Procedure] The control procedure of this embodiment will be described in detail below with reference to FIGS. 4 to 17b.

Figure 4 shows the CPU (20
1) shows the main routine.

When the CPU (201) is reset and the program starts, first, in step (Sl), the RAM (
212), initialize various registers, and make initial settings to put each device into the initial mode. Next, in step (S2), an internal timer of the CPU (201) is started. This internal timer determines the time required for one routine of this main routine, and its value is set in advance in step (Sl). Ru.

Next, the subroutines shown in steps (S3) to (S6) are sequentially called, and when the processing of all subroutines is completed, the process waits for the internal timer to end in step (S7), and then returns to step (S2). The time length of this one routine is used to count the various timers that appear in each subroutine, that is, the end of counting is determined for the various timer values based on how many times this one routine has been repeated.

Furthermore, when an interrupt request is received from the CPU (215) while various processes are being executed, the CPU (215)
).

Figures 5a and 5b show the main routine steps (S3
) shows the copy operation subroutine executed in ().

First, in step (510), it is determined whether the document insertion signal is rl. [The document insertion signal indicates that the document is inserted from the document table (51) into the RADF (50), and the leading edge of the document is inserted into the RADF (50).
When it is successfully detected in S8), it is set to "rl" [see step (5221)]. When the CPU (215) transmits that the original insertion signal is set to 1, the copy start flag is set to 1 in step (511).
1”.

Next, in step (512), the copy start flag is set to "1.
If it is set to '1', the main motor (Ml), developing motor, etc. are turned on in step (513), and the charging charger (4) and transfer charger (
7) etc., reset the copy start flag to "0", and set the timers (TA) and (TB). Then, in step (514) it is determined whether the main paper feed section (30) is selected, and if YES, the clutch of the overprint paper roller <37) is turned on in step <515); Then, turn on the clutch of the sketch paper roller (38). With this, the selected roll paper (31) or (3
3) is fed toward the timing roller (40>).

Next, when the judgment end timing of the timer (TA) is confirmed in step (517), the clutches of paper feed rollers (37) and (38) are turned off in step (518).

Further, when the judgment end timing of the timer (TB) is confirmed in step (519), the scan signal is set to rl in step (520). The scan signal is
As explained in step (5224) of FIG. 16a, this is a signal for transporting the original from the position of the sensor (ps9) to the position of light irradiation by the exposure lamp (21).

Next, in step (521), it is determined whether the timing signal is "1°".
This is to synchronize the leading edge of the original image formed above and the leading edge of the paper at the transfer position, and the following step (5232)
is set to "1". This timing signal is ``rl''
When the CPU (215) sends information that the timing roller (
40) Turn on the clutch. At this point, the roll paper begins to be conveyed from the timing roller (40) to the transfer position.

Next, in step (523) it is determined whether the sensor (PS5) is off-edge. The roll paper is cut as explained in FIGS. 6a and 6b, and when the cut trailing edge passes, the sensor (PSE) is turned off.

If the sensor (PS5) is off-edge, step (5)
24>, turn off the charger (4), reset the scan signal to "0", and turn off the timing roller (40).
) disengage the clutch.

Next, in step (525), it is determined whether the return signal is "1." The return signal indicates that the leading edge of the original is at the sensor (
PSIO) is set to “1” when detected by [
See step (5239). Therefore, when the CPU (215) transmits that the return signal has been set to "1.", it is determined in step (526) whether or not multi-copying has been completed.If it has not been completed, step ( Step 529) sets the copy start flag to 11'' and prepares to start the copy operation again. When the multi-copy is completed, that is, when the copy operation for the number of copies is completed, step (527) is executed. ) and the sensor (P
It is determined whether S6) is an off-edge. If the trailing edge of the paper passes the sensor (PS6) and the sensor (PS6) is off-edge, the developing motor,
Turn off the transfer charge (7), etc., and set the timer (TC). Further, in step (530), a timer (TC
), the main motor (Hl) is turned off in step (531), the results of the processing up to now are outputted in step (532), and this subroutine ends.

Figures 6a and 6b show the steps (S4) of the main routine.
) shows the paper cut subroutine that can be executed.

First, in step (540), it is determined whether the original image signal is I''1''. The original image signal has been inserted into RADF (50)! When the leading edge of the paper reaches the light irradiation position on the glass (27), it is set to "11" [step (52)].
29) For reference, when the CPU (215) transmits that this original image signal is set to "1.
The paper feed section (30) or (
Roll paper (31) or (33) set in
) is set.

This timer (T1) is set, for example, to the time it takes for the roll paper to be conveyed by an arbitrary intermediate dimension between the horizontal standard size and the vertical standard size of the roll paper.

Next, in step (542), it is determined whether the timing signal is "1°", that is, whether it is the timing to turn on the timing roller (40) and convey the roll paper to the transfer position. ”, step (547
>, and if it is set to '1', step (543
) to set the timing flag to "1". continue,
In step (544), it is determined whether the size discrimination end plug is "1.".When the determination of the size to cut the roll paper is completed, the size discrimination end plug is set to "1." [Step (558) Therefore, if it is set to '1', the process moves to step (547) and rO,
If so, the paper source (30
) or (32), a timer (T2) corresponding to the width size of the roll paper (31) or (33) is set. This timer (T2) is set to the time required to cut the roll paper into a horizontal standard size. Then, in step <546), the timer T2 set flag is set to 11. Set to .

Next, in step (547), the timer (T1) is subtracted,
In step (548), it is determined whether or not the timer (T1) has finished counting. If the timer (T1) has not finished counting, the process moves to step (559), and if it has finished, in step (549), the original image signal is The document image signal is reset to "I"O" when the trailing edge of the document passes the light irradiation position on the glass (27) [see step (5237)]. In other words, the original image signal is transmitted as the original is transported at a speed corresponding to the copying magnification.
It has a meaning as a signal indicating the image length determined by the image scanning direction length of the original and the selected magnification.
When the CPU (215) sends information that the timer 2 set flag has been reset to 0, it is determined in step (550) whether or not the timer 2 set flag is set to 0. If so, step (55
In step 8), set the size determination end flag to "1." If the timer 2 set flag is "0", the paper feed unit (30> or (32) selected in step (551)
A timer (T3) corresponding to the width size of the roll paper (31) or (33) set in is set. This timer (T3) is set to the time required to cut the roll paper into a horizontal standard size.

On the other hand, if the document is still passing through the light irradiation position and it is determined in step (549> that the document image signal is still set to "1"), the timer 2 set flag is set to "1" in step (553). ”. If the timer 2 set flag is set to 11, the paper feed unit (30) or (32) selected in step (554>)
A timer (T4) is set by correcting the timer (step 2) according to the width size of the roll paper (31) or (33) set in the paper roll. This timer (T4) is a timer (
T2) can be corrected to the time required to cut the roll paper into a vertical size and the paper can be set completely. And step (555
), reset the timer 2 set flag to r'0'' and set the timer T4 set flag to 11''.
In step (558), the size determination end flag is set to “I”1”.
Set to . On the other hand, the timer 2 set flag is “0”
If so, the paper source (3) selected in step (556)
Set the timer (T5) corresponding to the width size of the roll paper (31 inches or (33)) set in 0) or (32).This timer (T5) is used to cut the roll paper into a vertical size. Then, in step (557), the timer T5 set flag is set to I"1".
, and the size determination end flag is set to "1" in step (558).

That is, in the above cut size determination routine, the state of the original image signal is determined when the timer (step 1) finishes counting [see steps (548) and (549), and the original image signal is reset to 0. If so, it is determined that the cut is to be made into a horizontal standard size, and if it remains set to 11'', it is determined that the cut is to be made into a vertical standard size. Specifically, if the original image signal has been reset to "OJ" and the timing signal has already risen to "1" at this time, The timer (T2) is maintained in the set state, and if the timing signal has not risen to 11'', the timer (T3) for cutting to the horizontal standard size is set in step (551). On the other hand, if the timing signal rises to "1" while the original image signal remains set to rB, that is, the timer (T2
) is set, in step (554) this timer (T2) is corrected and a timer (T4) for cutting to a vertical size is set. Also, if the timing signal has not risen to 1"1", step (55
6) Timer (T5) for cutting to vertical size
Set.

After determining the size to be cut as described above, it is determined in step (559) whether or not the timing flag is 11''. Once started, steps (560), (564), (568), (
572), it is determined whether each timer set flag is 11'', and the following routine set in ``rl'' is executed. That is, each step (561), (565
), (569).

At (573), timer (T2), (T3), (1'4)
, (T5), each step (562), (5
66), (570), timer (T2) at <574)
, (73), (T4), and (T5) have finished counting, each step (563), (
567), (571).

(575) turns on the cutter (41), resets each timer set flag to "01," and resets the timing flag and size determination end flag to r. It will be cut to a standard size or vertical size.

FIG. 7 shows a key processing subroutine executed in step (S5) of the main routine.

In this subroutine, step <5100) processes the magnification up key (113), step (5101)
) to process the magnification down key (114), step (51
02) to process the interrupt key (112), step (51)
03) to process the paper size select key (117), and step (5104) to process the step exposure key (115)
, (116), and the document stop key (100) are sequentially executed in step (5105).

FIG. 8 shows a subroutine for processing the magnification up key (113) executed in step (5100).

First, in step (5110), the magnification up key (113
), the step (Sill) is confirmed.
The magnification key displays LED (124) to (129) are turned off, and 1/1000 is added to the magnification in step (5112). This is repeated every time the magnification up key (113) is pressed.As a result, if it is determined in step (5113) that the magnification exceeds the maximum setting value of 1.420, the magnification is increased to 1.420 in step (5114). Correct to.

FIG. 9 shows a subroutine for processing the magnification down key (114) executed in step (Slot).

First, in step (5120), use the magnification down key (114).
) is confirmed to be on-edge, step (5121)
Turn off the magnification key display LED (124) to (129), and change the magnification to 171000 in step (5122).
Subtract. This is repeated every time the magnification down key (114) is pressed, and as a result, step (5123)
If it is determined that the magnification has fallen below 0.500, the magnification is corrected to 0.500 in step (5124).

FIG. 10 shows the subroutine for processing the interrupt key (112) executed in step (5102).

First, when it is confirmed in step (5130) that the interrupt key (112) is on, the 0 display (148), which determines whether the interrupt copying display (148) is turned off, is turned off in step (5131). If so, the display (148> is lit in step (5132), the copy mode at that time is memorized in RAM (212), and if the 0 display (148) that allows interrupts is lit, the process is executed in step (5133). ) to turn off the display (148) and return to copy mode.

FIG. 11 shows a subroutine for processing the paper size select key (117) executed in step (5103).

First, when it is confirmed in step (5140) that the paper size selection key (117> is on-edge), it is determined in step (5141) whether or not the overprint paper section (30) has been selected.Overprint paper section ( 30) is selected, the sketch paper section (32) is selected in step (5142).Also, if the sketch paper section (32) is selected, the overlay paper section (30) is selected in step (5143). ). Then, in step (5144), the vapor size that can be set in the paper feed section (30) or (32) selected is displayed on the display section (132) or (133).

FIG. 12 shows a subroutine for processing step exposure keys (115) and (116) executed in step (5104).

First, in step (5150), the exposure up key (115
) is confirmed to be on-edge, step (S151)
It is determined whether the exposure step is the maximum value or not. If it is the fi value, the process moves to step (5156), and if it is not the maximum value, the exposure step is increased by one step in step (5152).Next, in step (5156), the exposure step data is sent to the dimming circuit (213). Send.

On the other hand, in step (5153), the exposure down key (116) is
) is confirmed to be on-edge, step (5154)
It is determined whether the exposure step is the minimum value or not. If it is the minimum value, the process moves to step (5156), and if it is not the minimum value, the exposure step is decreased by one step in step (5155).Next, in the same step (5156) as described above, the exposure step data is transferred to the dimming circuit (213). ).

The 13th [lA] shows a subroutine for processing the original stop key (100) that can be executed in step (5105).

First, in step (5160), the original stop key (10
0) is confirmed to be on-edge, step (5161
) to set the original stop signal to "1". continue,
In step (5162), the operation of each element of the copying machine main body (1) is stopped. At the same time, step (5163)
The copy start flag and scan signal are reset to 10'' and the timers (τA>, (rB), (rc) are reset.

FIG. 14 shows a subroutine for handling a document paper jam, which is executed in step (S6) of the main routine.

First, in step (5170), it is determined whether a trouble has occurred in the document conveyance system of the RADF (50). Trouble mainly refers to document jams, which are detected by a combination of each sensor (PS8) to (PSII) and a timer, and this detection is well known in the art.

If a trouble has occurred, it is determined in step (5171) whether the trouble flag is "11" or not, and if it has already been set to "1", the process moves to step (5180).

If the trouble flag has been reset to 10, that is, if this is the first judgment after the trouble has occurred, step (5) is executed.
172), the trouble plug is set to 11'', and step (5173) resets the copy operation, that is, turns off the charger (4), etc., and sets various flags for copy operation.
The timer is reset, and then step (517)
In step 4), it is determined whether or not the sensor (PS20) is turned on. If it is turned on, that is, if the leading edge of the roll paper has already reached the sensor (PS20) when the trouble occurs, the cutter is turned off at this point. Even if the paper is cut at step (41), it is determined that the paper has a sufficient length to be transported thereafter. Therefore, here in step (5175) Karataf 4
Turn on 1) and cut the roll paper.

Next, in step (5178), a timer (T8) is set. This timer (T8) can be set to the time until the cut paper is completely fed onto the discharge tray (48). Then, in step (517B), the paper conveyance system, that is, the timing roller (40), the conveyance belt (42)
, fixing device (43), discharge roller (44>, (47)
, transport belts (45) and (46) are started, and the process moves to step (5180).

On the other hand, in the step (5174), the sensor (PS20)
is off, that is, if the leading edge of the roll paper has not yet reached the sensor (PS20) when a problem occurs, the transport flag is set to "1" in step (5177), and the transport flag is set to "1" in step (5178). ), the operation of the paper conveyance system is started in the same manner as described above, and the process moves to step (5180).

In step (5180), it is determined whether the transport flag is rl, and if it is still reset to "OJ", the process moves to step (5185), and if it is set to "1", then [
see step (5177)], step (5181
), wait until the sensor (PS20) is turned on, and then turn on the cutter (41) in step (5182). continue,
In step (5183), the transport flag is reset to r□, and in step (5184), a timer (T8) is set.

In step (5185), the timer (τ8) is subtracted, and when it is confirmed in step (5186) that the timer (T8) has finished counting, the operation of the paper conveyance system is ended in step (5187).

On the other hand, the document conveyance system of the RADF (50) stops its operation based on the detection of the occurrence of a trouble.

With the above control, the roll paper is cut to at least the shortest length necessary for conveyance and then discharged, and the operator only has to deal with problems with the document.

When the trouble is resolved, select N at step (5170).

It is determined that the trouble flag is reset to "rO" in step (5179).

Figure 15 shows the optical system (20),! : RA D F (
50) shows the main routine of the CPU (215) that controls the CPU (215).

When the CPU (215) is reset and the program starts, first, in step (5200), various registers are initialized and initial settings are made to put each device into the initial mode.Next, step (5201)
starts the internal timer of the CPU (215).

This internal timer determines the time required for one routine of this main routine, and its value is set in advance at the step (520
0).

Next, the subroutines shown in steps (5202) and (5203) are sequentially called, and when the processing of all subroutines is completed, the process waits for the internal timer to end in step (5204), and then returns to step (5201). This one
The time length of the routine is used to count the various timers that appear in each subroutine, that is, the end of counting is determined based on how many times this one routine has been repeated for each timer value.

Also, if an interrupt request is received from the CPU (201) while various processes are being executed, the CPU (201) requests an interrupt in step (5205).
1) Perform data communication with.

FIG. 16 shows the lens control subroutine executed in step (5202) of the main routine, in which the motor (M2) is controlled in accordance with the copy magnification sent from the CPU (201) in step (5210), and the lens ( 25) Move the mirror (26).

Figures 17a and 17b show the main routine steps (
5203) shows the subroutine of the document transport foot roll executed in step 5203).

First, in step (5220) it is determined whether the sensor (PS8) is on-edge, and if it is on-edge, step (5220) is performed.
5221') sets the original insertion signal to "1" and turns on the original transport motor (M3). Now the manuscript is RAD
It is transported into F(50). Next, step (522
2) Determine whether the sensor (PS9) is on-edge or not.
If it is on-edge, that is, the leading edge of the document is connected to the sensor (PS
9), the document transport motor (M3) is turned off in step (5223), and the return signal and document insertion signal are reset to 10''.

Next, in step (5234) it is determined whether the scan signal is "1" or not, and if it is "1", [see step (520)], in step (5225)
Turn on. In this case, the motor (M3) is controlled at a speed according to the copy magnification, and the document is transported from the sensor (PS9) position. At the same time, the timers ("fD" and "TE") are set in step (5226). .Timer (
TD) is set to the time required for the leading edge of the document to reach the light irradiation position on the glass (27) from the sensor (PS9), taking into consideration the document transport speed according to the copy magnification. Also,
Similarly, the timer (TE) is set to a time at which the timing to turn on the timing roller (40) is issued, taking into consideration the document conveyance speed according to the copy magnification.

Next, in step (5227), the timer (TD) is subtracted, and in step (5228), it is determined whether or not the timer (TD) has finished counting. When the timer (TD) ends, that is, when the leading edge of the document reaches the light irradiation position, the document image signal is set to "1" in step (5229).

Next, in step (5230), the timer (TE) is subtracted, and when it is confirmed in step (5231) that the timer (rE) has finished counting, the timing signal is set to 1"1" in step (5232).

Next, in step (5233) it is determined whether the sensor (PS9) is off-edge, and if it is off-edge, step (5233) is performed.
5234) sets the timer (TF) and resets the timing signal to "O". The timer (TF) is set to the time required for the trailing edge of the document to pass from the sensor (PS9) to the light irradiation position, taking into consideration the document transport speed according to the copy magnification. Next, in step (5235), the timer (TF) is subtracted, and when it is confirmed that the timer (IF) has finished counting in step (5236), step (5235) is performed.
237), the original image signal is reset to "O".

Next, in step (5238) it is determined whether the sensor (PSIO) is on-edge, and if it is, the return signal is set to 11'' in step (5239), and in step (5240) it is determined whether the copy is completed or not. Determine. If copying is completed, step (5241) selects the switching claw (6
The document is ejected with 5> turned off. On the other hand, if the copying is not completed, the switching claw (65) is turned on in step (5242) to switch to document circulation.

Next, in step (5243) it is determined whether the sensor (PSII) is off-edge or not, and if it is off-edge, a timer (IC) is set in step (5244). Timer (
TG) is set to the time from when the trailing edge of the document passes the sensor (PSII) until it is completely discharged onto the discharge tray (60). Therefore, in step (S245), the timer (TG
) is subtracted, and when it is confirmed in step (5246) that the count of the timer (TG) has ended, in step (5247) the original conveyance motor (M3) is turned off and the return signal is reset to "0".

On the other hand, in step (524g), the document stop signal is set to "1".
”, and if rl, then [step-<51
61) Refer to step (5249) to turn off the document transport motor (H3). At the same time, in step (5250), the timing store number, return partner number, and original image signal are set to "0".
and reset the timer (TD), (TE), (TF
), (TG) and stop controlling the RADF (50).

[Other Examples] Note that the present invention is not limited to the above examples,
Various modifications can be made within the scope of the gist.

In particular, regarding the document scanning method, in addition to RADF, which circulates the document, it is also possible to use a method that transports the document one sheet at a time. There may be cases where the skew is greater than the capacity.

In the above embodiment, a paper detection sensor (PS) is used to operate the cutter (41) when a document transport problem occurs.
As for 20), a dedicated sensor is installed, but if a sensor for detecting roll paper jams, etc. has already been installed at that position, that sensor may also be used.

As is clear from the above explanation, according to the present invention, when the trouble of document withdrawal within the document conveyance device is detected, the roll paper that has been completely fed from the paper feed section is cut by the cutting means. Since the paper detecting means installed on the paper transport path at a distance required for subsequent paper transport from the position detects the leading edge of the roll paper, the roll paper is cut at least as long as necessary for subsequent paper transport. The paper is cut to the shortest length and then ejected, making it easier to use as the operator only has to deal with troubles with the document.Moreover, the roll paper is not cut to a length longer than necessary, making it economical. .

[Brief explanation of the drawing]

The drawings show an embodiment of the image forming apparatus according to the present invention, in which Fig. 1 is a schematic diagram of the entire apparatus, Fig. 2 is a plan view of the operation panel, Fig. 3 is a block diagram of the control circuit, and Fig. 4. 17a to 17b are flowcharts showing the control procedure. <1>... Copying machine main body, (2)... Photosensitive drum,
(20)...Optical system, (31), (33)...Roll paper, (40)...Timing roller, (41)...
... Cutter, (50) ... Automatic document circulation conveyance device (R
ADF), (PS8) to (PSII)...document detection sensor, (PS20)...roll paper detection sensor.

Claims (1)

[Scope of Claims] 1. In an image forming apparatus that is equipped with a document transport device and is capable of forming an image on a roll paper loaded in a paper feed unit, there is provided a means for detecting document transport trouble within the document transport device, and a roll. a cutting means for cutting paper; a paper detecting means provided on a paper transport path a length necessary for subsequent paper transport from a roll paper cut position by the cutting means; When detected,
An image forming apparatus comprising: a control means for cutting and discharging a roll paper fed from a paper feed section after the paper detection means detects the leading edge of the roll paper.