JPH08301482A - Paper conveyance control device for copying machine - Google Patents

Abstract

PURPOSE: To perform automatic discharge processing without an obstacle of residual paper started after removing of paper generating a jam in a copying machine. CONSTITUTION: This copying machine is provided with an automatic discharge processing mode set so as to automatically discharge paper 15 left in a conveying path before starting new copying work after removing paper 15 when generated a paper jam in the conveying path. At automatic discharge mode time, a paper conveying means is operated only for a time necessary for normally conveying paper between sensors S of the longest distance. In this prescribed time, all the paper detecting sensors S1 to S10 are set to a detection operation condition, to discharge the paper 15 detected by these sensors while supervising whether generating the paper jam is provided or not. When the paper 15 is not detected by any of the paper detecting sensors with a lapse of the prescribed time, the automatic discharge mode is ended.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine for making a copy on a cut sheet, and more particularly, when the sheet is still present in a conveying path after a paper jam generated inside the copying machine is dealt with. The present invention relates to a sheet conveyance control device of a copying machine for discharging.

[0002]

2. Description of the Related Art In general, the more complicated the function of a copying machine, the more complicated the conveyance path and the longer its total length. Therefore, although various improvements have been made to the method for transporting paper, it is impossible to eliminate paper jams (jams) in the transport path.

FIG. 13 shows a jam detection principle for a sheet conveyed in a conveying path. Transport path 1
The sheet 2 conveyed on the upper side has a plurality of sheet detection sensors S1,
The detection areas of S2 ... Now, these sheet detection sensors S1, S2 ... Detect the presence or absence of the sheet at a timing individually determined in advance, and (1) when the presence of the sheet 2 is not detected at the timing when the sheet 2 should pass, or (2) When the presence of the sheet 2 is detected at a timing when the sheet 2 should not be present, it is determined that the jam has occurred.

By the way, in a relatively high-quality copying machine such as a copying machine capable of performing double-sided copying or multiple copying (copying a plurality of times on the same side), the paper conveyed in the conveying path is jammed. When the error occurs, it is possible that some sheets are present in the transport path at the same time.

Conventionally, once a jam occurs, the operator removes all the sheets existing in the conveying path. However, the complicated transport path makes it virtually impossible for the operator to remove all sheets. Therefore, recently, a copying machine has been introduced in which the operator removes only the jammed paper and the other papers are automatically discharged (Japanese Patent Laid-Open No. 59-74).
844). The location of the jam is usually displayed on the console of the copying machine or the like, and this significantly reduces the operator's burden.

[0006]

However, there is a big problem in this automatic discharge processing by the copying machine. That is a problem when the operator removes not only the paper at the location where the jam has occurred but also the other paper existing on the transport path. This will be described with reference to FIGS. 14 and 15.

FIG. 14 shows a case where the two sheets 2A and 2B stopped on the conveying path 1 for jam clearance are both present at the positions detected by the sheet detection sensors S1 and S2. . In this case, for example, even if one of the sheets 2A is mistakenly removed during the jam processing, the copying machine can detect this by the corresponding sheet detection sensor S1. That is, in this case, the discharging operation may be started only for the sheet 2B that has not been removed, and it may be monitored whether or not the sheet 2B causes a jam on the transport path.

However, it is rather rare that all the sheets remaining in the conveying path are detected by the sheet detecting sensor. FIG. 15 shows three sheets of paper 2.
Among C to 2E, one sheet 2D is not detected by any sheet detection sensor. In this state, it is assumed that the operator mistakenly removes the paper 2B that does not cause a jam. The fact of this removal cannot be discerned by the copier. Therefore, when the copying machine stores the presence of the sheet 2D by the first sheet detection sensor S1 and the like, the jam is caused by the fact that the second sheet detection sensor S2 does not detect the presence of the sheet 2D within a predetermined time after restart of the sheet conveyance. And the automatic discharge process is stopped.

As described above, in the copying machine in which only the jammed paper needs to be removed, if the operator also removes the other papers, there is a problem that the automatic discharging process after the jam removal cannot be performed smoothly. .

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet conveyance control device for a copying machine, which can efficiently perform an automatic discharging process of the remaining sheet which is started after removing the jammed sheet.

[0011]

According to the present invention, when a paper jam occurs in a conveying path, the paper remaining in the conveying path after the corresponding paper is removed is automatically removed before starting a new copying operation. In a paper ejection control device of a copying machine having an automatic ejection mode adapted to eject the paper, a paper carrying means for carrying the paper in the carrying path, and a plurality of papers for detecting the paper carried by the paper carrying means A detection sensor,
In the automatic discharge mode, regardless of the detection state of the paper detection sensor, the paper conveyance means is operated for a predetermined time necessary for the paper to be normally conveyed between the sensors having the longest distance, A sheet discharge control unit that sets all the sheet detection sensors to a detection operation state at a time, and discharges the sheet detected by the sheet detection sensor at this time while monitoring the presence or absence of a paper jam. The paper discharge control means terminates the automatic discharge mode when none of the paper detection sensors detects the paper after the predetermined time has elapsed, so that the paper jammed paper in the transport path is removed. In the automatic ejection mode that automatically ejects the remaining paper before starting a new copy operation, the remaining paper can be detected reliably and the detected paper will not cause a paper jam. Whether it be discharged while monitoring the. Moreover, it is possible to prevent the paper conveying means from being uselessly ended by activating the paper conveying means for a predetermined time and ending the automatic discharge mode when none of the paper detecting sensors detects the paper.

By the way, the paper detection sensor used in the present invention may detect two or more papers during the above-mentioned predetermined time. In this case, this number of sheets can be integrated and used as data for subsequent conveyance control.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to embodiments.

FIG. 1 shows an outline of a copying machine to which the present invention is applied. In this copying machine, three-stage supply trays 12 to 14 are arranged inside a copying machine main body 11. These supply trays 12 to 14 are designed such that their bottom plates are lifted upward as the stored paper 15 is used, and the top paper is always in a predetermined position (height). Is set to.

Feed belts 16 to 18 are arranged slightly above the three-stage supply trays 12 to 14, respectively. When, for example, the upper feed tray 12 is selected for feeding paper, the corresponding upper feed belt 16
The air inside is sucked, and only one sheet 15 is sucked by the upper feed belt 16.

Since the upper feed belt 16 starts rotating at a predetermined timing, the sucked paper 15 is detected by the second paper detection sensor (hereinafter, the paper detection sensor is simply referred to as a sensor) S2. After being
It is transported in the direction of the vertical transport 21.
Paper 15 reaching the vertical transport 21
Are transported downward by this transport and reach the cash register transport 22. In the cash register / transport 22, the transfer timing is adjusted by the registration roll 23. As a result, the paper 15 which has started to be conveyed at a predetermined timing is detected by the fifth sensor S5.
Then, the toner image is transferred between the photoconductor belt 24 and the transfer device 25, and the toner image is transferred at this time.

The photosensitive belt 24 is an endless belt, and is rotated at a constant speed in the direction of arrow 29 by the drive roll 28 to which the driving force of the main motor 27 is transmitted. A charger 31 arranged close to the photoconductor belt 24 uniformly charges the surface of the belt.
The exposure station 32 exposes a document (not shown) set on the platen 33 with a built-in flash lamp,
The light image is irradiated onto the photoreceptor belt 24 after the charging. In this way, the electrostatic latent image is formed. After that, the electrostatic latent image is developed by the developing device 34 to form a toner image. This toner image is transferred to the above-mentioned paper 15.

The sheet 15 after the transfer of the toner image is conveyed upward by the prefuser transport 36 this time. The prefuser transport 36 is provided with a sixth sensor S6 for detecting the passage of the paper. The sheet 15 that has passed through the prefuser transport 36 passes through a fixing roll 37 and is thermally fixed there. The sheet 15 after fixing is conveyed further upward by the post fuser transport 38.

The post fuser transport 38 includes seventh to tenth sensors S7 to S10 for detecting a sheet.
In addition, three gates 41 to 43 for switching the transport path and an inverter unit 45 for inverting the front and back of the paper 15 are arranged. Of these, the seventh sensor S7 is near the fixing roller 37, and the eighth sensor S8 is the first sensor S8.
Are arranged in front of the gate 41.

The first gate 41 is a sheet inverter 45.
Switch to send or not. Paper fed to the inverter 45 and turned upside down, and the inverter 45
The sheet that has not been fed in the direction is conveyed to the location where the second gate 42 is arranged. Second gate 42
Is a gate for selecting whether to discharge the paper toward a discharge tray 46 provided on the upper surface of the copying machine main body 11 or to deliver the paper to a conveyance path in a subsequent stage. A ninth sensor S9 is provided near the discharge tray 46 to detect whether or not the paper is discharged.

A discharge tray 46 is provided by the second gate 42.
The sheet that has not been discharged in the direction reaches the third gate 43. The third gate 43 allows the sheet to pass through the horizontal transport 48 and to be purged (not shown).
It is selected whether the sheet is discharged toward the tray or the duplex tray 49. Tenth sensor S1
0 is arranged in the vicinity of the third gate.

By the way, the duplex tray 49 is
This tray is used for double-sided copying and duplicate copying on the same side. Ie Duplex Tray 4
The sheet accommodated in the sheet 9 is sent out toward the vertical transport 21 by the feed belt 51 at a predetermined timing, and the photosensitive belt 2 is moved in the same manner as described above.
4, the toner image is transferred again. A take-away roll (see FIG. 7) for transporting a sheet is arranged on the discharge side of the feed belt 51, as will be described later, and the first sensor S1 is arranged on the discharge side of the take-away roll. Has been done.

In this copying machine, the main motor 27 serves as a drive source for transporting the paper 15, so it is necessary to control various timings in synchronization with the rotation of the motor. For this reason, the encoder 53 is attached to the rotary shaft of the main motor 27, and the pulse signal output from the encoder 53 is used as a reference clock for controlling each part of the copying machine.

Further, takeaway rolls (not shown) are arranged near the discharge side of the middle feed belt 17 and the lower feed belt 18, respectively, as in the case of the first sensor S1. Third and fourth sensors S3 and S4 are arranged on the sheet carry-in side of the roll. The same applies to the second sensor S2. In this way, the second to fourth sensors S
Nos. 2 to S4 are opposite to the takeaway rolls in the positional relationship as compared with the first sensor S1.

FIG. 2 shows an outline of the control operation when the start button (not shown) is pressed in the copying machine having the above-mentioned structure. A start button for instructing the start of printing and the like is arranged on a console (not shown) of this copying machine. When this start button is pressed, the main motor 27 starts driving (step 1
(However, in the drawings, “step 1” is simply indicated by a circled number “”. Hereinafter, other steps and steps in other drawings are also expressed similarly.) CP not shown
In this state, the U (central processing unit) reads out a predetermined area of the RAM (random access memory), which is also not shown, and determines whether or not the copying machine is in a state in which purge control must be performed by this. (Step 2).

Here, the purge control is a control in the automatic discharge processing mode for discharging the paper still remaining in the transport path after removing the jam generated in the copying machine.
When a jam occurs and the corresponding sheet is removed from the transport path, data for performing the purge control is written in the predetermined area of the RAM described above.
Determines whether or not purge control is necessary based on this.

When it is necessary to discharge the sheet by the purge control (Y), the control is performed (step 3), and then the copying operation is performed (step 4). On the contrary,
When it is not necessary to discharge the paper by the purge control (step 2; N), the copying work is started immediately (step 4). When the copying operation is completed, the driving of the main motor 27 is stopped (step 5), and the control of the copying machine is completed (END).

FIG. 3 to FIG. 6 show the work of the stage where the paper discharge operation is not yet performed, that is, the start-up routine part of the automatic paper discharge as the details of the purge control. When the purge control is performed, the contents of the ON sensor counter (0S counter) are first cleared in FIGS. 3 to 6 (step 1). Here, the on-sensor counter is a counter that counts how many sheets are present on the conveyance path after the jam is removed. The count result of the on-sensor counter is R
It is written in a predetermined area of AM and is updated sequentially.

When the on-sensor counter is cleared, the CPU next resets the contents of the on-multiple counters (OM counters) provided corresponding to the sensors S1 to S10 to zero (step 2). The ON multiple counter is a counter that records the number of sheets counted by each of the sensors S1 to S10 within a predetermined time of the purge period. The count value of the ON multiple counter is also written in another predetermined area of the RAM described above, and its content is updated appropriately.

When the above work is completed, the CPU is in the RAM
The first sensor S1 is set in the sensor buffer (S buffer) assigned to the other area (step 3).
As a result, the CPU first starts the work of determining whether or not there is a sheet for the first sensor S1.

In this discrimination work, it is first discriminated whether or not the sensor indicated by the sensor buffer, that is, the first sensor S1 detects the sheet (step 4). When the first sensor S1 does not detect the sheet at present (N), it is next determined whether or not the count value of the ON multiple counter prepared for the first sensor is zero ( Step 5). If it is zero (Y), a detection request is set to detect when the detection output of the sensor (first sensor S1 in this case) indicated by the sensor buffer changes from off to on. (Step 6).

FIG. 7 is for explaining the significance of such a detecting operation. As described above, the takeaway rolls 61 and 62 for transporting the sheet are arranged on the discharge side of the feed roll 51, and the first sensor is provided at the subsequent stage. The fact that the first sensor S1 does not detect the sheet in step 4 of FIG. 3 means that the sheet does not exist in the vicinity of the sensor S1 at all, or if the sheet exists but is not detected at this time. There are two possible cases. In the latter case, the paper may be held between the takeaway rolls 61 and 62. In this case, the takeaway rolls 61 and 62 send out the paper when the main motor 27 starts driving, and the leading end of the takeaway rolls 61 and 62 is the first
Will be detected by the sensor S1. Therefore, in step 6, the on-change detection request is set in consideration of this state. If the content of the sensor buffer is not zero in step 5, the take away rolls 61 and 6 are taken.
Since the feeding of paper by 2 has already finished,
The on-change detection request is not set (step 5;
N).

When the ON change request of the first sensor S1 is set in step 6, the ON multiple counter is incremented by +1.
(Step 7). This represents a state in which this ON change request is set. Next, the CPU determines that the current sensor buffer contents are the first to ninth sensors S1 to S1.
It is checked whether it is S9 (step 8). This is to make the processing procedure different between the tenth sensor S10 and the other sensors S1 to S9. Since the first sensor S1 is set in the sensor buffer (see step 3), the sensor number indicated by the sensor buffer is incremented by 1 and updated (step 9).

Since the current contents of the sensor buffer are the first sensor S1, the second sensor S2 is newly written in the sensor buffer instead. The same operation as that of the first sensor S1 is performed for the second sensor S2. This second
If the paper is not detected even with the sensor S2 of
A request for ON change detection is set also for this, and the sensor buffer is updated (steps 4 to 9). In this way, the presence or absence of paper detection up to the tenth sensor S10 at the present time is checked, and the ON change detection request is set to the sensor in which no paper exists.

On the other hand, it is assumed that the sheet is detected by the second sensor S2 (step 4; Y). In this case, since the sensor indicated by the sensor buffer is the second sensor S2 (steps 10, 11; N), the on multiple counter for the next sensor designated by the sensor buffer is set to 1
Only is added (step 12). Here, the next sensor designated by the sensor buffer is as shown in Table 1 below.

[0037]

[Table 1]

That is, since the current sensor indicated by the sensor buffer is the second sensor S2, the ON multiple counter for the fifth sensor S5 is incremented by one. This is because, as understood from FIG. 1, if the sheet detected by the second sensor S2 is transported without causing a jam, the vertical transport 21
This is because it should reach the cash register transport 22 via the, and the front end thereof should be detected by the fifth sensor S5 arranged here.

The fifth sensor S thus added
If the count value of 5 is +1 (step 13; Y),
An ON change detection request for the fifth sensor S5 is set (step 14). This is the fifth sensor S5
This is for detecting the leading edge of the paper. After that, the on-jam timer for the sheet directed from the sensor indicated by the sensor buffer, that is, the fifth sensor S5 designated by the second sensor S2 is set (step 15). This is to set the maximum time until the leading edge of the paper is detected by the fifth sensor S5, and to determine that a jam has occurred when the leading edge of the paper is not detected within this time.

If the content of the ON multiple counter is not +1 in step 13 (N), the on-jam timer from the second sensor S2 to the fifth sensor S5 is directly set (step 15). If, for example, the sheet is detected by the first sensor S1, the on-change detection request is set for the fifth sensor S5 at this stage (step 14), so it is necessary to newly perform it. Because there is no.

When the on-jam timer is set, the sensor indicated by the sensor buffer, ie, the second sensor S
The off change detection request for 2 is set (step 16). This is the second sensor S currently being detected.
This is to check whether or not 2 can detect the trailing edge of the paper. Therefore, the maximum time until the second sensor S2 detects the trailing edge of the sheet is set by the off jam timer (step 17). After this, the on-sensor counter is incremented by 1 (step 18). This is to count that one sheet is detected by the second sensor S2.

When the work for the second sensor S2 is completed as described above, the content of the sensor buffer is updated (step 9), and the same work is performed for the third sensor S3. In this way, up to the seventh sensor S7,
Jam detection work is set when paper is detected.

When the eighth sensor S8 detects a sheet (steps 4, 10; Y), the CPU determines whether the copying machine main body 11 has a purge tray (step 19). Here, the purge tray is a tray provided on a sorter (not shown) connected to the copying machine main body 11.

When the purge tray is attached (Y), the ON multiple counter of the tenth sensor S10 is incremented by 1 (step 20). This is because, in this case, the paper is discharged to the outside of the machine through the horizontal transport 48 by the control of the second gate 42.
The leading edge of the sheet is detected by the tenth sensor S10. When the count value of the ON multiple counter of the tenth sensor S10 becomes +1 (step 21; Y), an ON change detection request for this sensor S10 is set (step 22). Then, from the eighth sensor S8 to the first
An on-jam timer is set in consideration of the carry distance to the sensor S10 of 0 (step 23). After that, for the eighth sensor S8, the off change detection request for detecting the trailing edge is set (step 16), and the off jam timer is set (step 17).
After this, the on-sensor counter is incremented by 1 as a result of the sheet detection by the eighth sensor (step 18).

On the other hand, when the copying machine main body 11 is not provided with the purge tray (step 19; N), the sheet is conveyed in the direction of the discharge tray 46, so the ninth sensor S is used.
The ON multiple counter of 9 is incremented by 1 (step 24).

Also in this case, if the count value of the ON multiple counter of the ninth sensor S9 is +1 (step 2).
5; Y), an on-change detection request is set for this sensor S9 (step 26), an on-jam timer is set (step 27), and it is determined whether the leading edge of the sheet is conveyed to the ninth sensor. Work settings are made. Thereafter, the off change detection request for detecting the rear end of the eighth sensor S8 is set (step 1
6), the off jam timer is set (step 1
7). Thereafter, the on-sensor counter is incremented by 1 as a result of the sheet detection by the eighth sensor (step 1
8).

Next, the ninth or tenth sensor S9, S1
A case where 0 detects a sheet will be described. In these cases (step 11; Y), since the sensor is arranged at the end of the conveyance path, only the off change detection request of these sensors S9 or S10 is set (step 16). Then, the off jam timer for the corresponding sensor is set (step 17), and the on sensor counter as a result of the paper detection is incremented by 1 (step 18).

When all the sensors up to the tenth sensor S10 have been checked in this way (step 8;
N), the CPU determines whether the on-sensor counter is zero (step 28). If the on-sensor counter is zero (Y), the paper is not being detected by the respective sensor. Therefore, in this case, the purge timer (P timer) is set to 2 seconds and the all-off flag (ALL OFF FLAG) is set in consideration of the presence of paper between the longest distance sensors. Step 29). This all-off flag indicates that none of the sensors S1 to S10 has initially detected the paper.

On the other hand, when the on-sensor counter is not zero (step 28; N), the purge timer is set to 5 seconds and the all-off flag is reset (step 30).

Here, the purge time of 5 seconds is sufficient for the first sensor S1 to pass through the ninth or tenth sensor S9 or S10 even if the first sensor S1 has a sheet and to leave the sheet. Say.

As described above, the automatic discharge start routine is completed. After this, the main motor 27 shown in FIG.
Is started (step 1 in FIG. 2), and purge control is performed (step 3 in FIG. 2).

FIGS. 8 and 9 show the ON processing of each sensor during the automatic discharge run (RUN) in this purge control. In the ON processing of each of the sensors S1 to S10, when the ON change (detection of the leading edge of the sheet) is performed with respect to the sensor that has issued the ON change request, this is processed.

In this processing, first, the on-jam timer indicated by the sensor buffer is reset (step 1). At this time, if multiple timers are set, only the timer that times out first is set.

Now, assuming that the sensor which has been turned on and which is indicated by the sensor buffer is the eighth sensor S8 (step 2; Y), a purge tray is provided in the copying machine main body 11 as in the routines shown in FIGS. It is judged whether or not it is attached (step 3). When the purge tray is attached (Y), the ON multiple counter of the tenth sensor S10 is incremented by 1 (step 4).

As a result, if the count value of the ON multiple counter of the tenth sensor S10 is +1 (step 5; Y), the first value is detected in order to detect that the leading edge of the paper reaches the tenth sensor S10. The ON change detection request is set for the sensor S10 of 10 (step 6). After that, the on-jam timer is set for this sensor S10 (step 7).

On the other hand, if the count value of the ON multiple counter of the tenth sensor S10 is not +1 (step 5; N), the ON jam timer for this sensor S10 is directly set.

Thereafter, an off change detection request is set to detect the trailing edge of the sheet for the eighth sensor S8, which has detected the on change (step 8). Then, the off jam timer is set for the eighth sensor S8 (step 9).

Next, the CPU determines whether or not the all-off flag described in the previous routine has been reset (step 10). When the all-off flag is not reset, that is, when the sensors S1 to S10 have not detected the sheet before the main motor 27 is started (N), the sheet is newly detected. It will be. Therefore, in this case, the all-off flag is reset (step 11), the setting of the purge timer for 2 seconds is canceled, and the purge timer is reset for 4 seconds (step 12). That is, the purge period of up to 6 seconds is set, and the paper discharge process is performed.

When the purge timer is reset, the ON multiple counter for the sensor indicated by the sensor buffer, that is, the eighth sensor S8 is decremented by 1 (step 13). This corresponds to the fact that the ON multiple counter is incremented by 1. As a result, if the count value of the ON multiple counter for the eighth sensor S8 does not become zero (step 1
4; N), the ON change detection request of the sensor S8 is set again (step 15).

On the other hand, when the ON multiple counter of the sensor S8 becomes zero, it is not necessary to detect the leading edge of the sheet, and therefore this routine is terminated without setting the ON change detection request.

Returning to step 3, if the copying machine main body 11 is not equipped with a purge tray (N), the ON multiple counter of the ninth sensor S9 is incremented by 1 (step 16). As a result, when the count value of the ON multiple counter becomes +1 (step 17; Y), an ON change detection request for detecting the leading edge of the sheet is set for the ninth sensor S9 (step 18). Then, the on-jam timer is set for the ninth sensor S9 (step 19). After that, the off change detection request for the sensor indicated by the sensor buffer, that is, the eighth sensor S8 is set (step 8), and the jam timer for this sensor S8 is set (step 10). The same applies hereinafter (steps 11 to 15).

Next, it is assumed that the ON-changed sensors indicated by the sensor buffer are the first to seventh sensors (steps 2, 20; N). In this case, the ON multiple counter for the sensor next to the sensor designated by the sensor buffer is set to 1
Is added (step 21). Here, the sensor next to the sensor designated by the sensor buffer has the same content as shown in Table 1 above. For example, if the sensor that has been turned on and is indicated by the sensor buffer is the second sensor S2, the ON multiple counter for the fifth sensor S5 is incremented by one. This is because the sheet should be conveyed to the fifth sensor S5 after the second sensor S2 detects the leading edge of the sheet, as described in the automatic discharge start routine of FIGS. .

If the count value of the +1 ON multiple counter becomes +1 as a result (step 22; Y),
An on-change detection request for detecting the leading edge of the sheet is set by this sensor (step 23). After this, the on-jam timer from the sensor indicated by the sensor buffer to the next instructed sensor is set (step 2).
4). In the above example, the on-jam timer for the sheet going from the second sensor S2 to the fifth sensor S5 is set. If the content of the ON multiple counter is not +1 in step 22 (N), the ON jam timer is set without setting the ON change request. This is because the ON change detection request has already been set.

After the on-jam timer from the on-changed sensor indicated by the sensor buffer to the next instructed sensor is set (step 24), the off-change detection for this on-changed sensor is performed. The request is set (step 8). Thereafter, the same operation as described above is performed (steps 9 to 15).

Finally, the sensor changed in the ON state, which is indicated by the sensor buffer, is the ninth or tenth sensor S9, S10.
If it is (step 20; Y), since these are the sensors arranged at the end of the conveyance path, only the off change detection request is set (step 8). Thereafter, the same operation as described above is performed (steps 9 to 15).

As described above, the sensors S1 to S1 in the automatic discharge run are
The description of the on-processing routine of S10 ends.

Next, the OFF processing of each sensor during the automatic discharge run will be described with reference to FIG. When the trailing edge of the sheet is detected within a predetermined time by the sensor that has requested the OFF change detection as a result of operating the main motor 27 to start the sheet conveyance, this content is written in the sensor buffer. The CPU resets the off-jam timers of these sensors written in this sensor buffer (step 1 in FIG. 10). Then, this routine is ended.
This is because it is determined that a jam has occurred unless the off-jam timer is reset within the predetermined time.

FIG. 11 shows a processing routine for a case in which the sensor for which the off jam timer or the on jam timer is set is timed out without being reset within the predetermined time as described above. is there. If at least one off jam timer or on jam timer has timed out, CP
U requests an emergency stop as if a jam has occurred (step 1). This means an emergency stop of the main motor 27 or the like, and such a stop process is performed by another routine not shown.

At the same time, the CPU has all the sensors S1 to S1.
For 0, the on change detection request and the off change detection request are reset (step 2). It also resets all off jam timers and on jam timers (step 3). This is because the conveyance of the sheet itself is stopped by the emergency stop, so that the timing work until the detection of the trailing edge or the leading edge of the sheet becomes meaningless. After this, a display request for displaying where the jammed sensor is is set (step 4). This allows
Jam processing during the automatic discharge run ends.

FIG. 12 shows a processing routine when the purge timer times out. In the automatic discharge start routine shown in FIG. 3 to FIG.
If the counter is zero, paper detection has not been performed at the initial stage, so set the purge timer to 2 seconds, and
The off flag was set (step 29 in FIG. 5). When the count value of the on-sensor counter is not zero, the sheet is detected by the sensor, so the purge timer is set to 5 seconds and the all-off flag is reset (step 30).

Therefore, when the all-off flag is set and the purge timer for 2 seconds has timed out (step 1 in FIG. 12; Y), the purge discharge operation for discharging the remaining paper from the transport path is performed. Is completed, and a flag indicating this completion is set (step 2).

On the other hand, when the all-off flag is reset (step 1; N), it means that the paper exists and the time of 5 seconds or 4 seconds has been set by the purge timer. . CP in this case
U needs to confirm that all the sheets on the transport path have been ejected after the time-out.

Therefore, the CPU clears the contents of the sensor counter set in the new area of the RAM to zero (step 3). Then, the first sensor S1 is set in the sensor buffer (step 4). Then, it is checked whether the ON multiple counter of the first sensor S1 is zero (step 5). The fact that this is not zero (N) means that there is a sheet on the conveyance path. Therefore, in this case, the sensor counter is incremented by 1 (step 6). Next, the CPU checks whether the sensor indicated by the sensor buffer is the tenth sensor S10 (step 7). If not, (N) the sensor buffer is updated (step 8).

As a result, the sensor indicated by the sensor buffer becomes the second sensor S2. The same operation is performed for the second sensor S2 if the ON multiple counter is not zero (steps 5 to 8). Hereinafter, the same applies to the tenth sensor S10.

On the other hand, if the corresponding ON multiple counters corresponding to the first to eighth sensors S1 to S8 indicated by the sensor buffer are zero (step 5; Y, 6; N),
Since there is no paper, the sensor buffer is updated immediately (step 8). For the ninth sensor S9,
Unless this sensor detects the paper (step 9;
Y), since it is unlikely that the paper is present on the conveyance path thereafter, the sensor buffer is updated (step 8). On the other hand, if the ninth sensor S9 is on (step 9; N), the sensor counter is incremented by 1 (step 6). This is because it is determined that there is a sheet on the transport path.

Also for the tenth sensor S10, if it detects a sheet, the sensor counter is incremented by 1 (steps 10 and 6). When the sheet is not detected (step 10; Y), the sensor counter is not incremented.

In this way, all the sensors S1 to S1 are
When the inspection work of the ON multiple counter corresponding to 0 is completed (step 7; Y), the CPU determines whether the count value of the sensor counter is zero (step 1).
1). If the sensor counter is zero (Y), since there is no sheet on the conveyance path, a flag indicating the end of purge discharge is set (step 2). On the other hand, if it is not zero (step 11; N), the purge timer is set to 1
Only seconds are set (step 12), and the sheet is ejected in the state where the jam is not detected. After that, the routine restarts from step 1 at the time-out. At this time, if the paper is completely discharged from the conveyance path (step 11; Y), the flag indicating the end of the purge discharge is set (step 2).

[0078]

As described above, according to the present invention, after the jammed paper in the conveying path is removed, the remaining paper is automatically ejected before the start of a new copying operation. In the mode, the remaining paper can be detected without fail, and the detected paper can be ejected while monitoring the occurrence of paper jam. Moreover, it is possible to prevent the paper conveying means from being uselessly ended by activating the paper conveying means for a predetermined time and ending the automatic discharge mode when none of the paper detecting sensors detects the paper.
It is possible to complete the discharging process in a shorter time as compared with the case where the discharging operation is performed for the time for completely discharging the sheet assuming that the sheet exists, and the copying operation can be made efficient.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a copying machine according to an embodiment of a sheet conveyance control device for a copying machine of the present invention.

FIG. 2 is a flowchart showing an outline of machine run control in the present embodiment.

FIG. 3 is a flowchart showing a part of an automatic discharge instruction routine in the present embodiment.

FIG. 4 is a flowchart showing another part of the automatic discharge instruction routine in the present embodiment.

FIG. 5 is a flow chart showing another part of the automatic discharge instruction routine in the present embodiment.

FIG. 6 is a flowchart showing another part of the automatic discharge instruction routine in the present embodiment.

FIG. 7 is a side view showing the first sensor S1 and its surroundings in the present embodiment.

FIG. 8 is a flowchart showing a part of an ON processing routine for each sensor during an automatic discharge run in the present embodiment.

FIG. 9 is a flowchart showing another part of the ON processing routine of each sensor during the automatic discharge run in the present embodiment.

FIG. 10 is a flow chart showing an OFF processing routine of each sensor during an automatic discharge run in the present embodiment.

FIG. 11 is a flowchart showing each on / off jam processing routine during an automatic discharge run in the present embodiment.

FIG. 12 is a flowchart showing a purge timer time-out processing routine in the present embodiment.

FIG. 13 is a principle diagram showing the principle of paper jam detection.

FIG. 14 is an explanatory diagram showing a state in which all the sheets are detected by a sensor when the copying machine is stopped.

FIG. 15 is an explanatory diagram showing a state in which a part of paper is not detected by a sensor when the copying machine is stopped.

[Explanation of symbols]

2, 15 ... Paper, 11 ... Copying machine main body, 21 ... Vertical transport, 22 ... Cash register transport, 36
... Prefuser transport, 38 ... Postfuser transport, 45 ... Inverter, 48 ... Horizontal transport, S1-S10 ... 1st-10th
Sensor.

Claims (1)

[Claims] 1. An automatic ejecting method in which, when a paper jam occurs in a conveyance path, the corresponding paper is removed and the paper remaining in the conveyance path is automatically ejected before a new copying operation is started. In a paper ejection control device of a copying machine having a processing mode, a paper conveyance means for conveying the paper in the conveyance path, a plurality of paper detection sensors for detecting the paper conveyed by the paper conveyance means, and the automatic ejection In the mode, regardless of the detection state of the paper detection sensor, the paper conveyance means is operated for a time necessary for the paper to be normally conveyed between the sensors of the longest distance, and the paper is conveyed at this predetermined time. Paper discharge control means for setting all the detection sensors to a detection operation state and discharging the paper detected by the paper detection sensor at this time while monitoring whether or not a paper jam has occurred. The paper discharge control means, when the predetermined time has elapsed and none of the paper detection sensors detects the paper,
A paper conveyance control device for a copying machine, characterized in that the automatic discharge mode is terminated.