JPH0485237A - Jam detecting device - Google Patents

Abstract

PURPOSE:To eliminate the need of providing timer means individually for every sheet member so as to simplify the constitution by setting the timer time according to the number of sheet members existing on the first transport path and monitoring the presence of a jam according to the timer time. CONSTITUTION:There are provided the first transport means M2 for transporting a sheet member on the first transport path to the second transport path and the second transport means M3 for transporting the sheet member transported to the second transport path by the first transport means to the next process. Subsequently, the presence of the sheet member on the second transport path is detected by a detection means 23, and the number of sheet members existing on the first transport path is counted by a counting means CM. When the counting means does not detect the leading end of a sheet member even in the lapse of the preset timer time, a jam detection signal showing that a jam occurs on the first transport path is generated by a timer means TM. According to the number of sheet members counted by the counting means CM and the presence of a succeeding document, the timer time is set by a control means 30.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a jam detection device that detects whether a sheet member such as a document is being conveyed without accumulation on a conveyance path. The present invention relates to a jam detection device suitable for application to an automatic document feeder.

[Prior art 1] As a method for detecting a paper jam, which is a phenomenon of abnormal conveyance in a conveyance path of a sheet member, a sensor is provided at the exit of the conveyance path, and a sensor is provided at the exit of the conveyance path, and A timer is set to a time slightly longer than the transport time to the exit, and when the sheet member starts to be transported from the transport start position, the timer is started at the time when this transport starts, and this timer starts counting the time. When the sensor detects the tip of the sheet member during operation,
A known method is to determine that a jam has occurred when the leading edge of the sheet member is not detected by the sensor even if the timer stops the time counting operation.

By the way, in recent automatic document feeders that are used in addition to copying machines, in order to improve processing capacity, the next document is transported to a predetermined position while the document (sheet member) is being ejected after processing. There is something I did.

FIG. 7 is an explanatory diagram for explaining the document conveying operation of such an automatic document feeder. In the figure, 50 is the first
a conveyance path 51 is a second conveyance path communicating with the discharge port 52;
53 is a conveyance belt that conveys the original on the first conveyance path 50 toward the second conveyance path 51; 54 is a conveyance motor that drives the conveyance belt 53; and 55 and 56 are the second conveyance path 51.
A paper ejection roller and a driven roller 57 eject the original document toward the ejection port 52, and a ## paper motor drives the paper ejection roller 55 and the driven a-roller 56.

In such an automatic document feeder, the processed document 58b is transferred to the second conveyance path 51 by the conveyor belt 53.
be transported to. At the same time, the subsequent document 58c is transported by the transport belt 53 and set at a predetermined position A on the platen P, while the original fi 58a, which was transported earlier to the second transport path 51, is transported by the paper ejection roller 55 and the driven roller. 56
It is discharged to the discharge port 52 by.

Therefore, in this automatic document feeder, when documents are being continuously fed onto the platen P, a plurality of documents may exist on the first conveyance path 50.

Note that the conveyance motor 54 and the paper ejection motor 57 rotate in synchronization with each other during such continuous feeding, and guide the documents being fed one after another to the ejection port 52. However, in the case of a long document, the preceding document is partially ejected from the ejection port 52 while the subsequent document is being transported to the predetermined position A, so that the processing of the subsequent document is not completed. If you wait for the original document to start being conveyed in the ejection direction, the preceding document will wait in the "discharged state" until the middle of the process, and there is a risk that it will be misunderstood as if a conveyance abnormality has occurred. Therefore, the paper ejection motor 5
7, if there is an undischarged document in the second conveyance path 51,
It can rotate independently and asynchronously with the transport motor 54.

In the automatic document feeder that continuously conveys documents one after another in this way, the first conveyance path 50! The problem is how to quickly detect a jam of a document that reaches the conveyance path 51 of @2.

Therefore, a configuration may be considered in which the conventional method described above is used to detect a jam of a document being conveyed in the ejection direction.

[Problems to be Solved by the Invention] However, as described above, there are often one or more originals in the first conveyance path 50, so if the above conventional method is applied as is, it will be difficult to provide multiple sheets of paper. There is a problem that the configuration becomes complicated.

Furthermore, if the first conveyance path 50 is long, it will be determined whether or not a jam has occurred for the first time after the conveyance time (timer time) required to pass through it has elapsed. When a jam occurs, the sheet member attempts to be conveyed until the conveyance operation is stopped in response to a jam detection signal, resulting in a problem that the sheet member may be bent or damaged.

The present invention has been made in view of these problems, and is capable of quickly detecting the presence or absence of a jam in a device that conveys sheet members in a form where a plurality of sheet members may exist on the same conveyance path.
It is an object of the present invention to provide a jam detection method that can determine a jam with a simple configuration.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a first conveyance means for conveying a sheet member on a first conveyance path to a second conveyance path, and a first conveyance means for conveying a sheet member on a first conveyance path to a second conveyance path. a second conveyance means for conveying the sheet member conveyed to the second conveyance path by the second conveyance path to the next process; an inspection means for detecting the presence or absence of the sheet member on the second conveyance path; a counting means for counting the number of sheet members present on the first conveying path, and when the counting means does not detect the leading edge of the sheet member even after a preset timer period has elapsed, it indicates that a jam has occurred on the first conveyance path. The apparatus includes a timer means for generating a jam detection signal, and a control means for setting the timer time according to the number of sheet members counted by the counting means and the presence or absence of a subsequent document.

[Function] According to the above configuration, the timer time is set according to the number of sheet members present on the conveyance path of vJl, so there is no need to provide a timer means for each sheet member, and the configuration is simplified.

Further, when there is one or more sheet members on the first conveyance path, jams are monitored according to the positional relationship with subsequent documents, so the presence or absence of jams can be quickly detected.

As a result, it is possible to prevent a jammed sheet member from being used for a long time, and to eliminate problems such as damage to the sheet member and change of order with subsequent sheet members due to being used for a long time.

[Example] Hereinafter, the present invention will be described in detail based on the illustrated example.

FIG. 1 is a sectional view showing one embodiment of the overall configuration of the conveyance mechanism of an automatic document feeder to which the jam detection device of the present invention is applied. There is a feeding section 3 that feeds the upper originals one by one, a transporting section 4 that transports the originals fed one by one to a predetermined position on the platen P, and a feeding section 4 that transports the originals fed one by one to a predetermined position on the platen P. anti-1
1i- and a reversing discharge unit 5 that guides the platen P toward a predetermined position again, and a paper discharge tray 6 on which the discharged original is stacked.
It consists of.

The paper feed section 3 has a big 7 tube roller 7 and an empty sensor 8.
, a separation roller 9, a registration sensor 10, a vibrating roller 7, and a motor M1 as a power source for the separation roller 9. The document placed on the paper feed tray 2 is moved downward by the pickup roller 7. A few documents are taken out from the original, and only the lowest document is separated by the separation roller 9 into a space 1 with a large loop margin.
1 is sent out. Here, the document whose direction has been changed along the outer side plate 12 passes through the straight guide section 13 and reaches the nip between the registration roller 14 and the pinch roller 15 of the conveyance section 4.

The conveyance section 4 includes the reno roller 14 and the pinch roller 15, a wide conveyance belt 16, and the conveyance belt 16.
a driving roller 17 and a driven roller 18 that rotationally drive the
It consists of a plurality of pinch rollers 19 that stretch the conveyor belt 16 over the top surface of the platen P, and a registration roller 14.
The original fed to the entrance of the register is sent out in the direction of the platen P by the rotation of the registration roller 14 in a state in which it is in pressure contact with the contact between the registration roller 14 and the pinch roller 15, and is sent out in the direction of the platen P at the same time as the registration roller 14. The paper is transported onto the platen P by the transport belt 16 which has started to move. Note that the registration roller 14 is connected to a conveyor belt drive motor M2.
An electromagnetic clutch G is interposed between them, so that the registration rollers 14 stop rotating while the conveyor belt 16 is rotating.

At this time, the registration sensor 10 remains on until the trailing edge of the document is sent out from the registration sensor 10, so the control section (not shown) starts rotating the registration roller 14 and the drive roller 17, and from the timing the registration sensor 10 detects the trailing edge of the document. The number of pulses applied to the motor M2, which is the power source for the drive row 217 and the registration roller 14, is counted until the timing when the document is turned off due to the passage, and the document size L1 is classified into standard document sizes based on the count value. Then, the motor M2 is stopped when pulses corresponding to the distance 10 from the position of the registration sensor 10 to the predetermined position A on the platen P are applied to the motor M2.

As a result, the original is set at a predetermined position A on the platen P.

Next, the reversing and discharging unit 5 includes a reverse roller 20, driven rollers 21g and 21b pressed against it, a switching claw 22 that transports the document reversely in the direction of the conveyor belt 16 with the front and back sides reversed, a paper discharge sensor 23, It consists of a sensor 24 for determining the stop timing during reverse feeding, a paper ejection roller 25, and a motor M3 as a power source for the reversing roller 20. The original that has been ejected is transported in the ejection direction by the reversing roller 20.At this time, if the switching claw 22 is as shown in the figure, the original is ejected to the paper ejection tray 6 by the 4# paper roller 25. However, when the switching claw 22 is switched to the reverse feed side, it is guided toward the driven roller 18@ of the conveyor belt 16, and is set at the predetermined position A on the platen P again by the reverse rotation of the conveyor belt 16. .

FIG. 2 is a block diagram showing the configuration of a control section for controlling the conveyance of a document in the present invention, and specifically, it is constituted by a microcomputer 30. As shown in FIG.

In the $2 diagram, the microcomputer 30 includes an empty sensor 8, a registration sensor 10, and a paper discharge sensor 23.
In addition to inputting each sensor output signal of the sensor 24 for detecting stop timing, there is also a clock pulse Φ1 that serves as a reference for the pulses PMI to PM3 applied to the motors M1 to M3.
tΦ2 is input. Further, as an output signal, a motor M1 for rotating the separation roller 9, etc. of the paper feed section 3;
Pulse PM applied to motor M2 for rotating the conveyor belt 16 and motor M3 for rotating the reversing roller 20
I to PM3, an on signal RCL to the registration roller clutch G for transmitting the rotation of the motor M2 to the registration roller 14, a drive signal SD to a solenoid (not shown) for switching the switching pawl 25, etc. are output. has been done.

Further, inside the microcomputer 30, a timer TM for jam detection and a document counter CN for counting the number of documents existing on the platen P are provided.

Below are the operation explanatory diagrams in Figure 3 and Figures 4 (a) to (f).
The jam detection operation of the above configuration will be explained with reference to the 7a-chart shown in FIG.

First, when the CPU 30 receives a document exchange signal indicating that the document to be fed onto the platen should be replaced with the next page from the main body of the copying machine, the CPU 30 performs a discharge start process and a feed start process as shown in FIG. A transmission start process is executed (steps 81 to S3).

The details of the discharge start process are shown in FIG. If so, start the discharge process (steps 81 to S
3).

That is, as shown in the explanatory diagram of FIG. 3, the document counter CN counts "+14" when the registration sensor 10 detects a fed document, and counts "-" when the discharge sensor 23 detects a discharged document. 1", so if the count value of the document force counter CN is not rOJ, it is determined that "there is a set document J" and the discharge motor M3 and the conveyance motor M2 are activated (step S20!521). Next, since there may be one or more originals on the platen P, the original counter CN
Check the count value of , and if the count value is "1", the leading edge of the document 58C is located at the paper ejection sensor 2 as shown in FIG.
T for a slightly longer time than the time required to reach position 3, TX. The value of is set in the timer TM. At the same time, start the process of monitoring whether the paper ejection sensor 23 is turned on (
Steps 822-524). However, when the number of originals existing on the platen P is [1] or more, the leading edge of the subsequent original will be at the position of the ejection sensor 23 at the time when the trailing edge of the preceding original is detected by the ejection sensor 23 through the process described later. Set the timer T to the value of the time required to reach Ty, which is slightly longer
Set to M.

On the other hand, the details of the feeding start process are shown in FIG. 4(c). It is checked whether there is a first-out document preceding the document to be fed (step 530), and if there is a first-out document, the transport motor M2 is activated (step 53).
1). Then, the document that has newly begun to be fed passes the position of the Rennost sensor 10, and a registration sensor off monitoring process is started to monitor that the registration sensor 10 is turned off (Step 32), and then the document counter CN is set to "+1". ”
(Step 33). In this case, if there is no first-fed document, when the registration sensor 10 detects the leading edge of the document, the transport motor M is moved to the predetermined position A for a time corresponding to the transport distance.
2 is activated, the document whose feeding has started is set at a predetermined position.

On the other hand, as the ejection operation progresses, the leading edge of the document being conveyed in the ejection direction reaches the position of the paper ejection sensor 23, and the paper ejection sensor 23 is turned on (step 540 in FIG. 4(d)).
After resetting the timer TM, a process for monitoring the time until the discharge sensor 23 turns off is started (step S41.542).

Then, when the trailing edge of the document passes the position of the paper discharge sensor 23 and the paper discharge sensor 23 is turned off (step 550 in FIG. 4(e)), the count value of the document counter CN is checked, and the count value is "1", it means that there is a subsequent document, so after setting the timer TM to a value of time T, which is slightly longer than the time Ty for the subsequent document to reach the position of the paper ejection sensor 23, the document is counter CN r-I
Decrement J (steps 351 to 553)
.

Time-open T set in the timer TM in step S23 of FIG. 4(b) or step S52 of FIG. 4(e). The value of T is decremented in synchronization with the rotation of the transport motor M2 in the timer count process shown in FIG. That is, the timer T set in the timer TM. or T
A value of 1 means that the clock pulse Φ1 (or Φ
2) is decremented at predetermined time intervals (steps 360 to 62). Then, when the decremented value becomes "0", a jam detection signal indicating that a jam has occurred on the conveyance path leading to the paper discharge sensor 23 is output (step 64).

Therefore, for example, if we consider a state in which three originals are being conveyed continuously as shown in FIG. 3, both the conveyance motor M2 and the paper ejection motor M3 are If it is in the activated state, a value of time open T1 is set in the timer TM when the trailing edge of the preceding original 58a passes, and whether the leading edge of the succeeding original 58b is detected by the paper ejection sensor 23 within the time T. The presence or absence of Noyam is determined by the presence of Noyam.

However, as shown in the time chart of FIG. 6, although the trailing edge of the preceding original 58a was detected by the paper ejection sensor 23, the ejection motor M2 was not activated and the subsequent original 58b started to be transported in the ejection direction. If not, the process of step 62 in FIG. 4(e) is not executed. That is, the timer TM is set to a value of time T when the trailing edge of the preceding document 58a is detected by the paper discharge sensor 23.
Since the transport motor M2 is stopped, the decrement is not performed. Then, the decrement operation is started by starting the transport motor M2. Therefore, the timer TM is at rest during the time period Tp until the transport motor M2 is started. As a result, the time T1 of timer TM has been extended by 11 hours,
The presence or absence of a jam in the subsequent document 58b is determined by this [extended time period "
It is determined by T, +TpJ.

Therefore, even if the transport motor M2 and the paper ejection motor M3 operate asynchronously, there is no possibility of erroneously identifying the presence or absence of a jam.

Furthermore, since the timer TM monitors the time from the rear end of the preceding document 58m to the leading edge of the succeeding document 58b, the presence or absence of a jam can be quickly detected even if the conveyance distance of the conveyor belt 16 is long.

On the other hand, the counter CN counts the number of originals present on the platen P, and when there is one original, the time T is equivalent to the time required for the leading edge of the original to reach the position of the paper ejection sensor 23. is set in the timer, and when there is one or more originals, the time required from when the trailing edge of the preceding original passes the position of the paper ejection sensor 23 until the leading edge of the succeeding original reaches one position of the paper ejection sensor 23. Since the time T1 corresponding to the current time is set in the timer, the presence or absence of a jam can be monitored with one timer without providing a timer for each document.

By the way, in the above embodiment, when there are multiple originals on the platen P, the time from the trailing edge of the preceding original to the leading edge of the succeeding original is monitored. It may also be something to monitor. That is, the fact that a plurality of originals can be accommodated means that the conveyance distance on the platen P is considerably long. Therefore, when detecting a document jam on such a long transport path,
If the conventional method is applied, jams must be continuously monitored over a long distance from the transport start position to the wandering point position. However, if the time from the trailing edge of the preceding document to the trailing edge of the succeeding document is monitored, the jam monitoring time can be shortened by at least the time required to transport one document, compared to the conventional method.
This is effective in quickly detecting jams.

Of course, the method of the above embodiment is the most effective.

In the embodiment, the document is ejected to the ejection tray 6 by the ejection motor M3, but the same method can be applied to a case where a conveying means is further provided in the next step.

[Advantageous Effects of the Invention 1] As explained above, in the present invention, a timer time is set according to the number of sheet members existing on the first conveyance path, and the presence or absence of a jam is monitored using this timer time. There is no need to provide a separate timer means, which simplifies the configuration.

Further, when there is one or more sheet members on the first conveyance path, jams are monitored according to the positional relationship with subsequent documents, so the presence or absence of jams can be quickly detected.

As a result, a jammed sheet member is prevented from being installed for a long time, and problems such as damage to the sheet member and changing order with subsequent sheets and -F members due to being installed for a long time are eliminated. I can do it.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the conveyance mechanism of an automatic document feeder to which the jam detection device of the present invention is applied, FIG. 2 is a block diagram showing the configuration of the control section, and FIG. 3 is a diagram showing the jam detection operation. An explanatory diagram for explaining, FIG. 4 is a 70-chart showing the jam detection operation means, and FIGS. 5 and 6 are timer times when the conveying means is synchronously driven and retched and asynchronously driven. Time chart for explaining the relationship between
The figure is an explanatory diagram for explaining the problems and outline of the conventional jam detection operation. 4... Conveying section, 5... Reversing and discharging section, 16... Conveying belt, 25... Conveying roller, M2... Conveying motor, M3... Paper discharge motor, 23... Paper discharge sensor, 30
...Microcomputer, CN...Counter, T
M...Timer patent applicant Nissuriki Co., Ltd. Figure 3 (eL) Figure 4 (b) (C) (a) Motor M3 (d) (e) (f) (a) Motor M3 Procedural amendment method Case Indication Patent Application No. 2-89 No. 2. Name of the invention Jam detection device 3, Person making the amendmentRelation to the case Patent applicant Address 430-1 Kobayashi, Masuho-cho, Minamikoma-gun, Yamanashi Prefecture Name Niska Co., Ltd. October 1990 5, Target of amendment Drawing 6° Amendment The contents are as per the attached sheet. Figure 5 Figure 6 Figure 2 Figure 3 (a) +, cb Figure 4 (b) (e) (Cn (f)

Claims (6)

[Claims] (1) A first conveyance means that conveys a sheet member on a first conveyance path to a second conveyance path, and a sheet member conveyed to the second conveyance path by this first conveyance means to the next process. a second conveyance means for conveying, a detection means for detecting the presence or absence of a sheet member on the second conveyance path, a detection means for counting the number of sheet members present on the first conveyance path, and a preset a timer means for generating a jam detection signal indicating that a jam has occurred on the first conveyance path when the detection means does not detect a leading edge or a trailing edge of the sheet member even after the elapse of the timer time, and the counting means; A jam detection device comprising: control means for setting the timer time according to the counted number of sheet members. (2) When the number of sheet members counted by the counting means is one or more, the control means detects that the rear end of the preceding sheet member conveyed to the second conveyance path is detected by the detection means. 2. The jam detecting device according to claim 1, wherein the timer means is set to a timer time that is slightly longer than the time required from 1 to 2 to detect the leading edge of a subsequent sheet member. (3) When the number of sheet members counted by the counting means is one or more, the control means detects the rear end of the preceding sheet member conveyed to the second conveyance path by the detection means. 2. The jam detecting device according to claim 1, wherein the timer means is set to a timer time that is slightly longer than the time required from when the trailing end of the subsequent sheet member is detected. (4) When the number of sheet members counted by the counting means is one, the control means sets a timer that is slightly longer than the time required until the leading edge of the sheet member is detected by the detection means. The jam detection device according to claim 1, wherein the jam detection device is set to . (5) The jam detection device according to claim 2 or 3, wherein the timer means is activated when the rear end of the preceding sheet member is detected by the detection means. (6) The jam detection device according to claim 4, wherein the timer means is activated when the detection means starts conveying the sheet member to the second conveyance path.