JPS6285261A - Control method for discharging of form - Google Patents

Abstract

PURPOSE:To improve the operativity of a copying machine by setting a form detection sensor so that the sensor is put in detecting operation only for a specific time after the start of an automatic discharging process mode and discharging a detected form while monitoring whether a jam occurs or not by the form detection sensor. CONSTITUTION:When a start button is pressed, a main motor 27 begins to be driven. Then, a CPU which is not shown in a figure reads a specific area in a RAM which is not shown either and sensors S1-S10 judge whether or not purging control which is control in automatic discharging process mode for discharging a form remaining in a removed. Then when the form needs to be discharged under the purging control, the control is carried out and then copying operation is performed. When the form needs not be discharged under the purging control, a copy is taken immediately. Then, the driving of the motor 27 is stopped after the copying operation, and the control over the copying operation is finished.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a copying machine that performs copying on cut paper, and in particular, the present invention relates to copying machines that make copies on cut paper, and in particular, when there is still paper in the conveyance path after a paper jam that has occurred inside the copying machine has been cleared. The present invention relates to an ejection control method for ejecting the paper when the paper is ejected.

"Prior Art" In general, the more complex the functions of a copying machine, the more complex its conveying path and the longer its overall length. Therefore, although various improvements have been made to paper conveyance methods, paper jams in the conveyance path cannot be completely eliminated.

FIG. 9 shows the jam detection principle for sheets conveyed through a conveyance path. The paper 2 transported on the transport path 1 is detected by a plurality of paper detection sensors S1, S2...
Pass through the detection areas of ... in order. These paper detection sensors S1, S2... detect the presence or absence of paper at individually predetermined timings, and (1) detect the presence of paper 2 at the timing when paper 2 should pass; If the paper 2 is not present or (2) the presence of the paper 2 is detected at a timing when the paper 2 should not be present, it is determined that a jam has occurred.

Now, in relatively high-end copying machines such as those that can perform double-sided copying and multiple copying (multiple copies on the same side), jams may occur in the paper being conveyed along the conveyance path. At this time, there is a possibility that several sheets of paper are being conveyed simultaneously on this conveyance path.

Conventionally, once a jam occurs, an operator removes all the paper present in the conveyance path. However, as the conveyance path becomes more complex, it has become virtually impossible for an operator to remove all the sheets. Therefore, recently, a copying machine has been introduced which automatically discharges the other sheets after only the paper that caused the jam is removed (Japanese Patent Laid-Open Publication No. 74844/1983).

Since the location where the jam has occurred is usually displayed on the console of the copying machine, this greatly reduces the burden on the operator.

[Problems to be Solved by the Invention] However, there is a big problem with this automatic ejecting process by the copying machine. This is a problem when the operator removes not only the paper where the jam occurred, but also other papers on the conveyance path. This will be explained using FIGS. 10 and 11.

In FIG. 10, two sheets of paper 2A and 2B that are stopped on the conveyance path 1 for jam removal are both detected by the paper detection sensor S1.
, S2. In this case, for example, even if one of the sheets 2A is mistakenly removed during jam processing, the copying machine can detect this with the corresponding sheet detection sensor S1. That is, in this case, it is sufficient to start the discharge operation only for the paper 2B that has not been removed, and monitor whether or not this paper 2B jams on the conveyance path.

However, the situation in which all the sheets remaining on the conveyance path are detected by the sheet detection sensor is extremely rare. FIG. 11 shows a state in which one sheet 2D among the three sheets 20 to 2E is not detected by any sheet detection sensor. Suppose that in this state, the operator also mistakenly removes the sheet 2B that has not caused a jam. The fact of this removal cannot be determined by the copying machine. Therefore, the copying machine uses the first paper detection sensor S1.
If the existence of this paper 2D has been memorized by, for example, the second paper detection sensor S2 does not detect this within a predetermined time after paper transport is resumed, it is determined that a jam has occurred, and the automatic ejection process is stopped. I'll let you.

As described above, in a copying machine where only the jammed paper has to be removed, if the operator also removes other sheets, there is a problem in that the automatic ejection process after removing the jam cannot be carried out smoothly.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a paper ejection control method that allows automatic ejection of remaining paper, which is started after removal of jammed paper, to be performed without any problem.

"Means for Solving the Problem" In the present invention, all paper detection sensors in the conveyance path are kept in a detection state for a predetermined period of time during the automatic ejection process that is performed after the jammed paper is removed. The detected paper is assumed to be a paper existing on the transport path and is transported while monitoring whether or not a jam occurs. In this case, if none of the paper detection sensors in the transport path detects a single sheet even after a predetermined period of time has elapsed from the start of the automatic ejection processing mode, it is assumed that no paper remains in the transport path and the paper is automatically ejected. It is possible to terminate the processing mode. When this automatic ejection process is completed, the mode can be changed to a copy operation mode if necessary.

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 accumulated and used as data for subsequent conveyance control.

"Example" The present invention will be described in detail with reference to Examples below.

FIG. 1 shows an outline of a copying machine to which the present invention is applied.

This copying machine has three supply trays 12 to 14 arranged inside a copying machine main body 11. These supply trays 12~
14, the bottom plate thereof is lifted upward as the stored paper 15 is used, and the paper in the first wheel is always set at a predetermined position (height). It has become.

Feed belts 16 to 18 are arranged slightly above each of the three stages of supply trays 12 to 14, respectively. For example, when the upper supply tray 12 is selected for paper supply, the air in the corresponding upper feed belt 16 is sucked, and only one sheet of paper 15 is sucked into the upper feed belt 16.

Since the upper stage feed belt 16 starts rotating at a predetermined timing, the sucked paper 15 is detected by the second paper detection sensor (hereinafter, in this specification, the paper detection sensor will be simply referred to as a sensor) 32. , vertical
It is conveyed in the direction of the transport 21. Vertical
The paper 15 that has reached the transport 21 is conveyed downward by this transport and reaches the register transport 22. In the register transport 22, the transport timing is adjusted by a registration roll 23. As a result, the paper 15 whose conveyance is started at a predetermined timing passes through the fifth sensor S5 and then passes between the photoreceptor belt 24 and the transfer device 250, and at this time, the toner image is transferred.

By the way, the photoreceptor belt 24 is an endless belt, and a drive roll 28 to which the driving force of the main motor 27 is transmitted
It is configured to rotate at a constant speed in the direction of arrow 29. A charger 31 placed close to the photoreceptor belt 24 charges the belt surface uniformly. The exposure station 32 exposes a document (not shown) set on a platen 33 with a built-in flash lamp, and irradiates the charged photoreceptor belt 24 with a light image. In this way, an electrostatic latent image is formed. After processing, the electrostatic latent image is transferred to developer 3.
4 to form a toner image. This toner image will be transferred to the paper 15 described above.

After the toner image has been transferred, the sheet 15 is now conveyed upward by the brief user transport 36. A sixth sensor S6 is arranged in the brief user transport 36 to detect the passage of paper. The paper 15 that has passed through the prefuser transport 36 passes through a fixing roll 37 and is thermally fixed there. After fixing, the paper 15 is further conveyed upward by the Bostoff user transport 38.

The Bostoff user transport 38 includes seventh to first O sensors S7 to SIO for paper detection, three gates 41 to 43 for switching the conveyance path, and an inverter unit 45 for reversing the paper 150. has been done. Among these, the seventh sensor S7 is connected to the fixing roller 37
An eighth sensor S8 is disposed near the first gate 41, and an eighth sensor S8 is disposed in front of the first gate 41.

The first gate 41 switches whether or not to feed the paper to the inverter 45. The paper that has been fed into the inverter 45 and has been turned upside down, and the paper that has not been fed in the direction of the inverter 45 are transported to a location where the second gate 42 is arranged. The second gate 42 is a gate for selecting whether to discharge the paper toward a discharge tray 46 provided on the top surface of the copying machine main body 11 or to pass it to a conveyance path at a later stage. A ninth sensor S9 is provided near the ejection tray 46, and is configured to detect whether or not paper is ejected.

Paper that is not ejected toward the ejection tray 46 by the second gate 42 reaches the third gate 43 . This third gate 43 selects whether the paper is to be discharged via the horizontal transport 48 to a purge tray (not shown) or to a duplex tray 49. The tenth sensor 310
It is located near the gate.

By the way, the duplex tray 49 is a tray used when making double-sided copies or duplicate copies on the same side. In other words, the paper stored in the duplex tray 49 is fed in the direction of the vertical transport 21 by the feed belt 51 at a predetermined timing, and is again transferred with a toner image by the photoreceptor belt 24 in the same manner as described above. become. On the discharge side of the feed belt 51, a takeaway roll (see FIG. 4) for conveying paper is arranged as will be explained later, and on the discharge side of this takeaway roll, a first sensor S1 is installed. It is located.

In addition, in this copying machine, the main motor 27 is used to drive the withdrawal of the paper 15? Therefore, it is necessary to control various timings in synchronization with the rotation of this motor.

Therefore, an encoder 5 is attached to the rotating shaft of the main motor 27.
3 is attached, and the pulse signal outputted from this is used as a reference tarokku for controlling each part of the copying machine.

Further, a first sensor S is located near the discharge side of each of the middle feed belt 17 and the lower feed belt 18.
Takeaway rolls (not shown) are arranged in the same way as in the case explained in connection with No. 1, and third and fourth sensors S3 are installed on the paper input side of these takeaway rolls.
, S4 are arranged. The same applies to the second sensor S2.

In this way, the second to fourth sensors S2 to S4 are arranged in an opposite manner to the takeaway roll compared to the first sensor S1.

FIG. 2 schematically shows the control operation when a start button (not shown) is pressed in the copying machine configured as described above. A start button for instructing the start of printing, etc. is arranged on a console (not shown) of this copying machine. When this start button is pressed, the main motor 27 starts to be driven (step ■). In this state, the CPU (Central Processing Unit), not shown, reads a predetermined area of the RAM (Random Access Memory), also not shown, and thereby determines whether or not the copying machine is in a state where purge control is required. to decide(
Step ■).

Here, the purge control is control in an automatic ejection processing mode for ejecting paper remaining in the conveyance path after removing a jam generated in the copying machine. When a jam occurs and the relevant paper is removed from the transport path, data for performing purge control is written in the predetermined area of the RAM, and the CPU performs purge control based on this data. It will be necessary to determine whether or not it is necessary.

If it is necessary to eject paper using purge control (Y),
This control is performed (step ■), and the copying operation is then performed (step ■). On the other hand, if it is not necessary to eject paper using purge control, step
, the copying operation will start immediately (step ■). When the copying operation is completed, the driving of the main motor 27 is stopped (step ■), and control of the copying machine is ended (end).

FIG. 3 shows the details of the purge control at a stage where the paper is not yet ejected automatically, that is, the start-up routine. When purge control is performed, the contents of the on-sensor counter (OS counter) are first cleared in FIG. 3 (step 2). Here, the on-sensor counter is a counter that counts how many sheets of paper are present on the feeding path after the jam has been removed. The counting result of the on-sensor counter is written into a predetermined area of the RAM and updated sequentially.

When the on-sensor counter is cleared, the CPU then zeros out all the contents of the on-multiple counter (0M counter) provided corresponding to each sensor S1 to SIO (
Step ■). 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 period of the purge period. The count value of this ON multiple counter is also written to another predetermined area of the RAM, and its contents are updated as appropriate.

When the above operations are completed, the CPU sets the first sensor S1 in a sensor buffer (S buffer) allocated to another area of the RAM (step 2). As a result, C
The PLI first starts determining whether or not paper is present with respect to the first sensor S1.

In this determination work, it is first determined whether or not the sensor indicated by the sensor buffer, that is, the first sensor S1, is detecting paper (step 2). If the first sensor S1 is not currently detecting paper (N), it is next determined whether the count value of the ON multiple counter prepared for the first sensor is zero ( Step ■).

If it is zero (Y), a detection request is set to detect when the detection output of the sensor indicated by the sensor buffer (in this case, the first sensor 31) changes from off to on. (Step ■).

FIG. 4 is for explaining the significance of such a detection operation. As described above, on the discharge side of the feed roll 51, there is a takeaway roll 61. for paper conveyance.
62 is arranged, and the first sensor is provided at the rear stage. The fact that the first sensor S1 has not detected paper in step ① in Figure 3 means that there are two cases: there is no paper near this sensor S1 at all, or there is paper but it is not detected at this point. There are two possible cases. The latter has paper on takeaway roll 61.6
It may be held between 2. In this case, when the main motor 27 starts driving, the takeaway roll 6
1.62 feeds out the paper, and its tip is the first sensor S
1 will be detected. Therefore, in step (2), a request for detecting an ON change is set taking this state into consideration. If the contents of the sensor buffer are not zero in step (2), the on-change detection request is not set because the paper feeding by the takeaway rolls 61 and 62 has already been completed (step (2); N).

When the ON change request for the first sensor S1 is set in step (2), the ON multiple counter is incremented by 1 (step (2)). This represents the state in which this ON change request is set. Next, the CPU checks whether the current contents of the sensor buffer are the first to ninth sensors S1 to S9 (step 2). This is the 10th sensor SIO
This is to make the processing procedures different between the sensor S1 and the other sensors S1 to S9. Since the first sensor S1 is set in the sensor buffer (see step 2), the number of the sensor indicated by the sensor buffer is incremented by 1 and updated (step 2).

Since the current content of the sensor buffer is the first sensor S1, the second sensor S2 is newly written to the sensor buffer instead. The same operation as for the first sensor S1 is performed for the second sensor S2. This second sensor S2
If the paper is not detected even after this, a request for on-change detection is set for this as well, and the sensor buffer is updated (steps ① to ①). In this way,
The presence or absence of paper detection up to the tenth sensor S10 at the present time is checked, and an on-change detection request is set for the sensor for which no paper is present.

On the other hand, it is assumed that the paper is detected by the second sensor S2 (step 2; Y). In this case, since the sensor indicated by the sensor buffer is the second sensor S2 (
Step O1■;N), increment the ON multiple counter for the next sensor indicated by the sensor buffer by 1 (step 0).

The next sensor designated by the sensor buffer is as shown in Table 1 below.

(Left below) Table 1: Since the current sensor indicated in the sensor buffer is the second sensor S2, the ON multiple counter for the fifth sensor S5 is incremented by one. As can be understood from FIG. 1, if the paper detected by the second sensor S2 is conveyed without causing a jam, it will be transferred to the register transport 22 via the vertical transport 21. This is because the tip should be detected by the fifth sensor S5 located here.

If the count value of the fifth sensor S5 added in this way is +1 (step @; Y), an on-change detection request for this fifth sensor S5 is set (step 2). This is because the fifth sensor S5 detects the leading edge of the paper.

After this, the sensor indicated by the sensor buffer i.e.
An on-jam timer is set for the sheet directed from the fifth sensor S2 to the fifth sensor S5 (step 2). This is to set a maximum time until the leading edge of the paper is detected by the fifth sensor S5, and if the leading edge of the paper is not detected within this time, it is determined that a jam has occurred.

Note that if the content of the ON multiplex counter is not +1 in step 0 (N), the fifth sensor S
The on-jam timer up to 5 is directly set (step ■). For example, if the paper has been detected by the first sensor S1, an on-change detection request is set for the fifth sensor s5 at this stage (step ■), so there is no need to perform a new detection. That's because there isn't.

Once the on-jam timer is set, an off-change detection request is set for the sensor indicated by the sensor buffer, that is, the second sensor S2 (step @). This is to check whether the second sensor S2, which is currently performing detection, can detect the trailing edge of the sheet. For this reason,
The off-jam timer is set for the maximum time until the second sensor S2 detects the trailing edge of the paper (step O).

After this, the on-sensor counter is incremented by 1 (
Step @). This is to count when one sheet of paper is detected by the second sensor S2.

When the work on the second sensor S2 is completed as described above, the contents of the sensor buffer are updated (step
), a similar operation is performed for the third sensor S3.

In this way, settings are made for the jam detection work when the seventh sensor S7 is detecting paper.

Now, if the eighth sensor S8 detects paper (steps ■, ■; Y), the CPU determines whether a purge tray is attached to the copying machine main body 11 (step O).
. Here, the purge tray refers to a tray provided on a non-transferable sorter connected to the main body 11 of the copying machine.

If the purge tray is attached (Y), the ON multiple counter of the 10th sensor 310 is incremented by 1 (
Step (2io). This is because in this case, the paper is discharged outside the machine via the polysyntal transport 48 under the control of the second gate 42, so the tenth sensor 3
At step 10, the leading edge of the paper is detected. When the count value of the ON multiple counter of the tenth sensor s1o becomes +1 (Step @; Y), an ON change detection request for this sensor 310 is set (Step 2). Then, an on-jam timer is set that takes into account the transport distance from the eighth sensor S8 to the tenth sensor S10 (
Step c3). After this, regarding the eighth sensor S8,
After that, an OFF change detection request for @ detection is set (
(Step 0), the off-jam timer is set (Step 0). Thereafter, the on-sensor counter is incremented by 1 as a result of paper detection by the eighth sensor (step 0).

On the other hand, if the copying machine main body 11 does not have a purge tray (step ■; N), the paper is conveyed in the direction of the ejection tray 46, so the ON multiple counter of the ninth sensor S9 is incremented by 1. (Step ■).

Also in this case, when the count value of the ON multiple counter of the ninth sensor S9 is +1 (Step @; Y), an ON change detection request is set for this sensor S9 (Step 1S), and the ON jam timer is set. The sheet is set (step O), and a work setting is performed as to whether or not the leading edge of the sheet is conveyed to the ninth sensor. After this, the 8th
Regarding the sensor S8, an off change detection request for rear end detection is set (step @), and an off jam timer is set (step ■). Thereafter, the on-sensor counter is incremented by 1 as a result of paper detection by the eighth sensor (step @).

Next, a case where the ninth or tenth sensor 39 or 310 detects paper will be described. In these cases (step 0
;Y) is the sensor placed at the end of the transport path, so
Only the off-change detection request for these sensors S9 or S10 is set (step 2). The off-jam timer for the corresponding sensor is then set (step 0), and the on-sensor counter as a result of paper detection is incremented by 1 (step O).

When all the sensors up to the tenth sensor 310 have been checked in this way (step ■; N), the CPU
determines whether the on-sensor counter is zero (step @'). If the on-sensor counter is zero (Y), then the paper is not being detected by the respective sensor. Therefore, in this case, taking into account that there is paper between the sensors at the longest distance, set the purge timer (P timer) to 2 seconds, and set the all off flag (^shiL OFF FLAG). (step [phase]). This all-off flag is
This indicates that all sensors S1 to S10 do not initially detect paper.

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

Here, the purge time of 5 seconds is sufficient time for even if there is paper at the first sensor S1, it passes through the ninth or tenth sensor S9 or 310 and exits the machine.

In this way, the automatic discharge start routine ends.

Thereafter, the driving of the main motor 27 shown in FIG. 2 is started (step 2 in FIG. 2), and purge control is performed (step 2 in FIG. 2).

Figure 5 shows the automatic discharge run (RU) in this purge control.
It shows the ON processing of each sensor in N). In the on-processing of each of the sensors S1 to S10, processing is performed when the sensor that has made the on-change request is turned on (detection of the leading edge of the paper).

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

Now, suppose that the sensor that has turned on and is indicated by the sensor buffer is the eighth sensor S8 (step
;Y), copying machine main body 1 in the same way as the routine shown in FIG.
It is determined whether 1 has a purge tray (
Step ■). If a purge tray is attached (Y
), the on-multiple counter of the tenth sensor S10 is incremented by 1 (step ■).

As a result, if the count value of the ON multiple counter of the tenth sensor S10 is +1 (step ■; Y), the first
An on-change detection request is set for the tenth sensor S10 in order to detect that the leading edge of the paper reaches the sensor 310 (step 2). Thereafter, an on-jam timer is set for this sensor 310 (step 2).

On the other hand, if the count value of the ON multiple counter of the tenth sensor 310 is not +1 (step ■; N),
The on-jam timer for this sensor S10 will be directly set.

Thereafter, an off-change detection request is set for the eighth sensor S8 whose on-change has been detected to detect the trailing edge of the sheet (step (2)). And this eighth sensor S
8, an off-jam timer is set (step ■).

The CPU then performs the all-off operation described in the previous routine.
Determine whether the flag has been reset (step ■). If the all-off flag has not been reset, that is, if all sensors S1 to S310 have not detected paper before starting the main motor 27, then (N) paper has been newly detected. become. Therefore, in this case, the all off flag is reset (step o), the 2 second setting of the purge timer is canceled, and the purge timer is reset to 4 seconds (step ■).
. That is, a purge period of up to 6 seconds is now set, and paper ejection processing 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 counted down by 1 (step 0). This corresponds to the fact that the ON multiplex counter was previously incremented by 1. As a result, if the count value of the ON multiple counter for this eighth sensor S8 does not become zero (Step 2; N), the ON change detection request for this sensor S8 is set again (Step 2).

On the other hand, if the ON multiple counter of this sensor S8 becomes zero, there is no need to detect the leading edge of the paper, so this routine ends without setting an ON change detection request.

Returning to step (2), if the copying machine main body 11 does not have a purge tray (N), the ON multiple counter of the ninth sensor S9 is incremented by 1 (step (Ii
! l). As a result, if the count value of the ON multiple counter becomes +1 (Step @; Y), an ON change detection request for detecting the leading edge of the paper is set for the ninth sensor S9 (Step @). Then, an on-jam timer is set for this ninth sensor S9 (
step 0). Thereafter, an OFF change detection request is set for the sensor indicated by the sensor buffer, that is, the eighth sensor S8 (step ■), and a jam timer for this sensor S8 is set (step ol). The same applies hereafter (steps 0 to ■).

Next, assume that the sensors that have turned on and are indicated by the sensor buffer are the first to seventh sensors (steps ■, ■:
N). In this case, the ON multiple counter for the sensor next to the sensor specified by the sensor buffer is incremented by 1 (step 0). Here, the sensor next to the sensor specified by the sensor buffer is the same as shown in Table 1 above.

For example, if the sensor indicated by the sensor buffer that has turned on is the second sensor S2, the on multiple counter for the fifth sensor S5 will be incremented by one. This is because, as described in the automatic discharge start routine of FIG. 3, after the second sensor S2 detects the leading edge of the paper, the paper should be conveyed to the fifth sensor S5.

If the count value of the ON multiple counter becomes +1 as a result (Step 2; Y), an ON change detection request for detecting the leading edge of the paper with this sensor is set (Step 2). Thereafter, an on-jam timer is set from the sensor indicated by the sensor buffer to the next sensor specified (step [Yes]). In the previous example, the on-jam timer will be set for the paper going from the second sensor S2 to the fifth sensor S5. In addition, the content of the ON multiplex counter increases by 1 at step Φ.
Otherwise (N), the on-jam timer will be set without setting the on-change request. This is because the ON change detection request has already been set.

After the on-jam timer is set from the on-changed sensor indicated by the sensor buffer to the indicated next sensor (step @), a request for off-change detection for this on-changed sensor is set. (Step ■). Thereafter, operations similar to those described above are performed (steps ① to ①).

Finally, if the sensor that has changed to ON and is indicated by the sensor buffer is the 9th or 10th sensor S9 or S10, step ■;Y), since these are the sensors placed at the end of the conveyance path, the OFF change is detected. Only the request is set (step ■).

Hereafter, the same operations as described above are performed (steps ~
■).

This concludes the explanation of the turn-on processing routine for each sensor S1 to S10 during the automatic discharge run.

Next, with reference to FIG. 6, the process of turning off each sensor during the automatic discharge run will be explained. As a result of operating the main motor 27 and starting conveyance of the paper, if the trailing edge of the paper is detected within a predetermined time for the sensor for which the OFF change detection request was made, this content is written into the sensor buffer. C.P.
U resets the off-jam timers of these sensors written in this sensor buffer (step 2 in FIG. 6). Then this routine ends. This is because if the off-jam timer is not reset within a predetermined time, it will be determined that a jam has occurred.

FIG. 7 shows a processing routine when a sensor with an off-jam timer or an on-jam timer set is not reset within the predetermined time as described above and times out.

If at least one off-jam timer or on-jam timer times out, CP[J assumes that a jam has occurred and requests an emergency stop (step
). This means an emergency stop of the main motor 27, etc., and such a stop process is performed in another routine (not shown).

Along with this, the CPU performs the following for all sensors S1 to S10:
Reset the on-change detection request and the off-change detection request (step ■). Also reset all off-jam timers and on-jam timers (step ■)
. This is because the conveyance of the paper itself is stopped by the emergency stop, so the time-keeping operation up to the detection of the trailing edge or leading edge of the paper becomes meaningless. After this, a display request is set to display the location of the sensor where the jam occurred (step 2). This completes the jam processing during the automatic discharge run.

FIG. 8 shows a processing routine when the purge timer times out. In the automatic discharge start routine shown in Figure 3, if the on-sensor counter is 0, paper has not been detected at the initial stage, so the purge timer is set to 2 seconds and the all-off flag is set. (Step O in Figure 3). Also, on-sensor
If the count value of the counter was not zero, the paper was detected by the sensor, so the purge timer was set to 5 seconds and the all-off flag was reset (same step).

Therefore, if the all-off flag is set and the 2-second purge timer times out (Step ■; Y in Figure 8), the purge ejection operation for ejecting the remaining paper from the conveyance path ends. Assuming that the process has been completed, a flag indicating the end is set (step ■).

On the other hand, if the all-off flag has been reset (step 2; N), it is assumed that paper is present, and a time of 5 or 4 seconds has been set by the purge timer.

In this case, the CPU needs to confirm that all the sheets on the conveyance path have been ejected after the timeout.

Therefore, CPtJ clears the contents of the sensor counter set in the new area of the RAM to zero (step 2). Thereafter, the first sensor S1 is set in the sensor buffer (step 2). And this first sensor S1
Check whether the ON multiplex counter is zero (step ■). The fact that this is not zero (N) means that there is paper on the conveyance path. Therefore, in this case, the sensor counter is incremented by 1 (step ■).

Next, CPLI indicates that the sensor indicated by the sensor buffer is the
Check whether the sensor SIO is 0 (step ■
). Since this is not the case (N>updating of the sensor buffer is performed (step ■).

As a result, the sensor indicated by the sensor buffer becomes the second sensor S2. Similar operations are performed for the second sensor S2 if its ON multiple counter is not zero (steps ① to ①). The same applies hereafter up to the tenth sensor S10.

On the other hand, if the corresponding ON multiple counters for the first to eighth sensors S1 to S8 indicated by the sensor buffer are zero (step ■; Y1; N), there is no paper and the sensor buffer is updated immediately. is carried out (step ■). As for the ninth sensor S9, unless this sensor detects the paper (step ■; Y), it is unlikely that the paper will be present on the conveyance path after this.
The sensor buffer is updated (step ■).

On the other hand, if the ninth sensor S9 is on (step ■; N), the sensor counter is incremented by 1 (step ■). This is because it is determined that there is paper on the conveyance path.

Regarding the tenth sensor S10, if it detects paper, the sensor counter is incremented by 1 (
Step 0, ■). If paper is not detected (step @l; Y), the sensor counter is not incremented.

When the inspection work of the ON multiple counters, etc. corresponding to all the sensors S1 to S510 is completed in this way (step ■; Y), the CPU determines whether the count value of one sensor counter is zero (step 0). If the sensor counter is zero (Y), there is no paper on the conveyance path, so a flag indicating the end of purge discharge is set (step 2). On the other hand, if it is not zero (
Step @;N), a purge timer is set for one second (step 2), and the paper is ejected without any jam being detected.

After this timeout, the routine restarts from step ■. At this time, if the paper has been completely discharged from the conveyance path (step 0; Y), a flag indicating the end of purge discharge is set (step ■).

``Effects of the Invention'' As explained above, according to the present invention, since the conveyance control is performed while accurately grasping the paper remaining on the conveyance path after jam removal, the operator is given strict instructions on which paper to remove when removing the jam. This improves the operability of the copying machine. Of course, jam detection is also performed on paper remaining in the conveyance path after the paper that caused the jam has been removed, so jams that occur on the conveyance path can be perfectly managed.

[Brief explanation of drawings]

1 to 8 are for explaining one embodiment of the present invention, of which FIG. 1 is a schematic configuration diagram showing an example of a copying machine to which the paper ejection control method of the present invention is applied, and FIG. Figure 2 is a flowchart showing the outline of machine run control, Figure 3 is a flowchart showing the automatic discharge start routine, Figure 4 is a side view showing the first sensor S1 and its surroundings, and Figure 5 is a flowchart showing the automatic discharge start routine. FIG. 6 is a flowchart showing the sensor ON processing routine; FIG. 6 is a flowchart showing the sensor OFF processing routine during the automatic discharge run; FIG. 7 is a flowchart showing each sensor ON/OFF jam processing routine during the automatic discharge run; FIG. 9 is a flowchart showing the purge timer timeout processing routine, FIG. 9 is a principle diagram showing the paper jam detection principle, and FIG. 10 is an explanatory diagram showing a state in which all sheets of paper are detected by the sensor when the copying machine is stopped.
FIG. 11 is an explanatory diagram showing a state in which a part of the paper is not detected by the sensor when the copying machine is stopped. 2.15... Paper, 11... Copy machine body, 21... Vertical transport, 22...
...Register transport, 36...Prifuser transport, 38...Bostoff user transport, 45...Inverter, 48... Horizontal Transport, S1
~S10...First to tenth sensors. Applicant: Fuji Xerox Co., Ltd. Agent

Claims (1)

[Claims] 1. When a paper jam occurs in the conveyance path, the paper remaining in the conveyance path is automatically ejected after removing the relevant paper before starting a new copying operation. In a copying machine equipped with an automatic ejection processing mode, all paper detection sensors placed on the conveyance path are set to a detection operation state for a predetermined period of time from the start of the automatic ejection processing mode, and the paper detected at this time is A paper ejection control method characterized by ejecting paper while monitoring whether or not a paper jam occurs using a paper detection sensor. 2. A patent claim characterized in that when none of the paper detection sensors in the conveyance path detects a single sheet of paper even after a predetermined period of time has elapsed from the start of the automatic discharge processing mode, the automatic discharge processing mode is ended. The paper ejection control method according to item 1. 3. The paper ejection control method according to claim 1, wherein the paper detection sensor in the conveyance path adds up the number of sheets detected within a predetermined time from the start of the automatic ejection processing mode. 4. Paper ejection according to claim 2, characterized in that when the copying machine is instructed to start a new copying operation, the automatic ejection mode is shifted to this copying operation mode upon completion of the automatic ejection processing mode. Control method.