JP3275532B2 - Jam type determining method and jam clearing method for image forming apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining the type of jam used in an image forming apparatus and a method for clearing a jam.

[0002]

2. Description of the Related Art Various types of arrangements have been devised for detecting and eliminating the occurrence of a jam in the vicinity of a paper feed cassette in an image forming apparatus. One example is disclosed in
No. 22834 and JP-A-63-106236, which will be briefly described below.

The configuration disclosed in Japanese Patent Application Laid-Open No. Sho 59-22834 makes it possible to simplify a jam clear operation occurring near a paper cassette (performing only by removing and loading a paper cassette). is there.

More specifically, FIG. 6 shows a state in which a paper cassette 102 is loaded in a copying machine main body 100, and FIG. 7 shows an enlarged state of a broken line portion in FIG. I have. As shown in the latter figure, a magnet 104 is provided at the leading end of the paper cassette 102, and a reed switch 108 is provided at a predetermined position of the vapor chute 106 in correspondence with the magnet 104. Thus, the loading / unloading of the paper cassette 102 can be detected.

FIG. 8 is a block diagram of a jam clearing system. As shown in this figure,
Sampling monitor circuit 112 of control unit 110
Is connected to the above-described reed switch 108, a clock pulse generator 114, and the jam detecting device 11
6. It is connected to the display device 118. The jam detecting device 116 is for detecting occurrence of a jam near the paper cassette 102.

According to the above configuration, the combination of the reed switch signal “a” indicating the open / closed state of the reed switch 108 and the jam signal “b” indicating the detection result by the jam detector 116 is determined by the sampling monitor circuit 112.
The determination is made at predetermined time intervals based on the clock signal c from the clock pulse generator 114, and the result is output to the display device 118. With this, the display according to the status at each point in time (for example, "Can be copied" if it is normal, "Jam has occurred" if a jam has occurred, "Jam has occurred" / "Paper is being replenished" if the paper cassette has been removed, Jam clear When the rear paper cassette is loaded, "copying is possible" becomes possible, and when a jam occurs near the paper cassette 102, only the loading and unloading operations of the paper cassette 102 without opening and closing the copier body 100. To clear the jam.

However, according to the above configuration, a jam near the paper cassette 102 can be detected, but the type of the jam cannot be detected. Therefore, for example, when a paper jam occurs in the middle of the transport path after a certain amount of paper is fed from the paper cassette 102, the paper cassette 102 may be pulled out.
In this case, the sheet is torn off, and a part of the sheet remains in the transport path.

An arrangement capable of solving this problem is disclosed in
It is disclosed in Japanese Patent Application Laid-Open No. 3-106236, and will be briefly described below.

In the configuration disclosed in Japanese Patent Application Laid-Open No. 63-106236, if a paper jam occurs near the paper cassette, the paper cassette is locked to prevent the paper cassette from being removed, thereby solving the above-mentioned problem. Things.

[0010] More specifically, as shown in FIG.
22 are provided. The paper transport unit 122 transfers the paper fed by the paper feed roller 124 to the registration roller 12.
6, a first paper feed path 128 for guiding to
And a second paper feed path 132 that conveys the paper sent from the printer 26 to the copy processing unit 130. Of these, the first
A detection switch 134 is provided in the paper feeding path 128 of the printer, and detects the passage of the paper.

FIG. 10 shows a schematic configuration of a jam clearing system. As shown in FIG.
6 is a jam detecting means 138, a front cover opening / closing detecting means 1
40 and the solenoid 144 of the locking means 142. The front cover opening / closing detecting means 140 detects whether the front cover of the apparatus main body is opened or closed. Further, the locking means 142 is
4, a lock lever 146, and a compression coil spring 148. When excited, the claw of the lock lever 146 is engaged with the engagement hole 150 of the paper cassette 120.

According to the above-described configuration, the detection switch 134 detects whether or not the sheet has passed before the predetermined time elapses after the start of the sheet cassette 120. If the sheet is not detected, the jam signal is output. Jam detection means 13
8 to the CPU 136. This allows the CPU
136 activates the locking means 142 and causes the paper cassette 1
Lock 20. Therefore, the user performs the jam clearing operation by opening the front cover of the apparatus main body.
It is possible to solve the problem that the paper is torn. When the front cover is opened, an opening signal is output to the CPU 136 by the front cover opening / closing detecting means 140, whereby the solenoid 144 is demagnetized.

However, in the case of the structure disclosed in this publication, the paper is not fed at all from the paper cassette 120 due to abrasion of the paper feeding roller 124 or the like, and the paper is left as it is. Registration roller 12
Even if the paper does not reach the sheet 6 (in such a case, the paper cassette 120 may be removed), the jam can be cleared unless the front cover of the apparatus body is opened and closed each time. It is inconvenient because it cannot be done. Further, in this case, even if the front cover of the apparatus main body is opened, a jammed sheet cannot be found, so that a trouble such as being confused by a jam clearing operation occurs.

In general, the configurations disclosed in the above publications can be said to have advantages and disadvantages, respectively, because jams generated near the paper storage means such as a paper cassette are collectively captured. .

In the present invention, in consideration of the above fact, when a jam occurs in the vicinity of a paper storage means such as a paper cassette, the type of the jam is determined, and a jam clear operation corresponding to the type of the jam is performed. An object of the present invention is to provide a method for determining the type of jam for image formation and a method for clearing the jam.

[0016]

According to the first aspect of the present invention, there is provided a paper storage means for storing paper, a paper supply means for feeding paper from the paper storage means, and a paper supply means for feeding paper from the paper supply means. Image forming apparatus, comprising: a conveying unit that conveys a sheet along a predetermined path; and a sheet detecting unit that is provided in the middle of the conveying path of the conveying unit and near the sheet storing unit and that detects arrival of the sheet. When a first predetermined time has elapsed from the start of paper feeding by the paper feeding unit, if the arrival of the paper is not detected by the paper detecting unit, it is determined that a jam has occurred, and after the determination of the occurrence of the jam, the second determination is further performed. Operating the conveying means for a predetermined time, and determining whether a misfeed jam or a paper delay jam based on whether or not the arrival of the paper is detected by the paper detection means when the second predetermined time has elapsed. To have.

According to a second aspect of the present invention, there is provided a sheet storing means for storing sheets, a sheet feeding means for feeding sheets from the sheet storing means, and a sheet fed from the sheet feeding means to a predetermined path. The image forming apparatus is applied to an image forming apparatus including: a conveying unit that conveys the paper along the paper path; If the arrival of the sheet is not detected by the sheet detection means when a first predetermined time has elapsed from the start of sheet feeding by the means, it is determined that a jam has occurred,
After the occurrence of the jam is determined, the transport unit is further operated for a second predetermined time, and when the second predetermined time has elapsed, whether the misfeed jam or the paper delay jam is determined based on whether or not the arrival of the sheet is detected by the sheet detection unit. However, in the case of a misfeed jam, it is possible to clear the paper storage means from the apparatus main body by allowing the paper storage means to be detached from the apparatus main body, and in the case of a paper delay jam, to remove the paper storage means from the apparatus main body. The jam clear operation is made possible by preventing the opening of the main body of the apparatus.

[0018]

The operation of the present invention described in claim 1 is as follows.

After the paper is fed from the paper storage means by the paper feeding means, the paper is conveyed along a predetermined path by the conveying means.

Here, in the present invention, the sheet detecting means for detecting the arrival of the sheet is provided at a position near the sheet storing means in the middle of the conveying path by the conveying means. When the first predetermined time has elapsed,
If the arrival of the sheet is not detected by the sheet detecting means, it is determined that a jam has occurred.

After determining that a jam has occurred, according to the present invention, the conveying means is further operated for a second predetermined time. And
Whether the misfeed jam or the paper delay jam is determined based on whether or not the arrival of the sheet is detected by the sheet detection means when the second predetermined time has elapsed. Therefore, it is possible to determine the type of jam that has occurred in the vicinity of the sheet storage unit, which has not been realized conventionally.

The operation of the present invention described in claim 2 is as follows. The description of the same parts as those of the first aspect will not be repeated.

According to the present invention, if a misfeed jam has occurred as a result of the discrimination, the sheet storage means is allowed to be separated from the apparatus main body. Thus, the user can perform the jam clearing operation by detaching the sheet storage unit without opening the apparatus main body. Therefore,
Since the user does not need to perform an unnecessary opening operation of the apparatus main body, the trouble of the jam clearing operation can be saved.

On the other hand, if it is determined that a paper delay jam has occurred, the paper storage means is prevented from being separated from the apparatus main body, and the apparatus main body is allowed to be opened. As a result, the user performs the jam clearing operation by opening the apparatus main body. Therefore, it is possible to solve the problem that the paper is torn off due to the paper storage means being detached despite the paper delay jam.
For this reason, there is no problem that a part of the paper remains in the apparatus main body and it takes time to remove the paper.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 3 is a perspective view showing the appearance of a copying machine (electrophotographic copying machine) 10 as an image forming apparatus. The copying machine 10 includes a document cover 12 and a copying machine body 14 as an apparatus body. An image forming section 16 is provided above the inside of the copying machine main body 14, and a sheet feeding section 18 is provided below the image forming section 16. Further, on the outer peripheral portion of the copying machine main body 14, covers such as a front cover 20, a right central cover 22, and a right lower cover 24 are provided so as to be openable and closable. Further, a power switch 26 is provided on the upper right side of the copying machine body 14,
A display unit 28 such as an LCD screen, a start button 30, and the like are provided at the upper end on the front side.

FIG. 2 shows one of the paper cassettes 32 as a paper storage means to be loaded in the above-described paper supply section 18 in a plurality of stages. Paper 34 can be stored in the paper cassette 32. In addition, a paper feeding unit 36 is disposed immediately above the paper cassette 32. Paper feeding means 36
A rod 38, a plurality of paper feed rollers 40 fixed to the rod 38 at predetermined intervals, and a solenoid (not shown) that is connected to the axial end of the rod 38 and rotates the rod 38 by a predetermined amount when excited. , Comprising
It is provided on the copying machine body 14 side. When the paper 34 runs out, the paper cassette 3 is moved in the direction of arrow A in FIG.
2 is extracted and replenished.

The paper cassette 32 and the copying machine main body 1
A paper cassette attachment / detachment sensor 42 is provided in 4. The paper cassette attachment / detachment sensor 42 includes a magnet 44 and a reed switch 46. Magnet 44
Is attached to the end of the side wall portion 32A of the paper cassette 32 on the side of the loading direction (the direction opposite to the direction of arrow A). The reed switch 46 is provided at a position facing the magnet 44 in the copying machine main body 14. When the paper cassette 32 is loaded, the reed switch 46 conducts due to the magnetic force of the magnet 44 and the paper cassette 32 is pulled out. Is turned off. Note that the paper cassette attaching / detaching sensor 42 does not necessarily need to be configured by the magnet 44 and the reed switch 46, but may be configured by a photo sensor, a limit switch, and the like.

Further, a lock means 48 is provided in the paper cassette 32 and the copying machine main body 14. More specifically, the solenoid 5 is provided in the copying machine main body 14.
0, lock lever 52, and extension coil spring 54
And so on. The lock lever 52 is pivotally supported by a pin 56 at an intermediate portion in the longitudinal direction. The proximal end of the lock lever 52 is connected to the distal end of the plunger 58 of the solenoid 50 so as to be relatively rotatable. Further, a claw 52A is formed at the tip of the lock lever 52, and the top wall 32 of the paper cassette 32 is correspondingly formed.
At a predetermined position of B, an engaging hole 60 with which the claw 52A can be engaged is formed. The other end of the tension coil spring 54 whose one end is locked in the copying machine main body 14 is locked to the claw 52A of the lock lever 52 described above. Accordingly, the claw 52A of the lock lever 52 is normally urged upward (in a direction in which the claw 52A is disengaged from the engagement hole 60) by the tension coil spring 54. However, when the solenoid 50 is excited, the plunger 58 of the solenoid 50 is retracted against the urging force of the extension coil spring 54, and the claw 52A is engaged with the engagement hole 60.

On the other hand, FIG. 1 schematically shows only a necessary portion of a transport path from the paper cassette 32 to the photosensitive member 62. As shown in this figure, a transport roller pair 64 as transport means is disposed at a predetermined position on the downstream side in the transport direction of the paper 34 with respect to the paper feed roller 40 of the paper cassette 32. The sheet 34 is transported while being nipped by the transport roller pair 64. A registration roller pair 66 (registration means in a broad sense) is provided at a predetermined position on the downstream side in the transport direction of the sheet 34 with respect to the transport roller pair 64. The skew of the sheet 34 is corrected by the registration roller pair 66. In addition, a registration sensor 68 as a sheet detection unit including a photo sensor, a proximity sensor, a micro switch, and the like is provided at a position where the registration roller pair 66 is provided. Has been detected. Further, a photoconductor 62 and a transfer roller 70 are disposed at a predetermined position on the downstream side of the registration roller pair 66 in the transport direction of the sheet 34.

As shown in FIG. 4, the above-mentioned paper cassette attachment / detachment sensor 42 and registration sensor 68 are connected to a controller 72. A cover opening / closing sensor 74 such as a limit switch for detecting opening / closing of the right lower cover 24 and the like is also connected to the controller 72. Further, the controller 72 includes a paper feeding unit 36 (more precisely, a solenoid that rotates the paper feeding roller 40), a transport roller pair 64 (more precisely, a main motor that rotates the transport roller pair 64),
The image forming unit 16, the lock unit 48 (more precisely, the solenoid 50 of the lock unit 48), and the display unit 28 are also connected.

The controller 72 includes an internal timer A and an internal timer B. The internal timer A is shown in FIG.
After the sheet feeding operation by the sheet feeding roller 40 located at the position (C) is started, the leading end of the sheet 34 is moved to the position (A) in FIG.
This is for measuring a normal required time (Y time; this Y time corresponds to the “first predetermined time” in the present invention) until the pair reaches the registration roller pair 66 located at the position. Further, after the internal timer B starts the transport operation by the transport roller pair 64 located at the position (B) in FIG. 1, the leading end of the paper 34 reaches the registration roller pair 66 located at the position (A) in FIG. The usual time required until (X
Time; this X time is the “second predetermined time” in the present invention.
).

The operation of this embodiment will be described below with reference to the flowchart shown in FIG.

When the start button 30 is pressed after the power switch 26 is turned on, first, at step 80, a signal from the registration sensor 68 is captured. Then, step 8
In step 1, the solenoid is excited to rotate the paper feed roller 40 by a predetermined amount. As a result, the paper 3
4 is fed. At this time, in step 82, the internal timer A is started simultaneously. Next, at step 83, Y
It is determined whether the time has elapsed. If the determination in step 83 is negative, this determination is repeated until Y time has elapsed,
If the determination in step 83 is affirmative, it is further determined in step 84 whether the output from the registration sensor 68 has changed.

If the result in step 84 is negative, that is, if no jam has occurred, the process returns to step 80. On the other hand, if the determination in step 84 is affirmative, that is, if the sheet 34 has not reached the registration roller pair 66 when the Y time has elapsed, it is determined that a jam has occurred. In this case, a stop signal is output to the image forming unit 16 in step 85. Thereby, the image forming operation is stopped. Next, at step 86, the internal timer B is started. At this point, the transport operation by the transport roller pair 64 is continued. Next, at step 87, it is determined whether or not the X time has elapsed. If the determination in step 87 is negative, this determination is repeated until X time has elapsed, and if the determination is affirmative in step 87, a stop signal is output to the main motor driving the transport roller pair 64 in step 88. Thus, the transport operation by the transport roller pair 64 is stopped.

Next, at step 89, the registration sensor 6
It is determined whether or not the output from 8 has changed. If the determination in step 89 is affirmative, that is, if there is a change in the output from the registration sensor 68, the sheet 34 has been engaged with the pair of conveying rollers 64 (the sheet feeding operation is performed and the sheet 34 Has been reached), so
It is determined that a paper delay jam has occurred. Therefore, in step 90, a message such as "Paper is jammed" is displayed on the display unit 28. Next, at step 91, the solenoid 50 of the lock means 48 is excited. As a result, the plunger 58 of the solenoid 50 is retracted, and the lock lever 52 rotates around the pin 56 against the urging force of the extension coil spring 54. Therefore, the lock lever 52
Of the paper cassette 32 is engaged with the engagement hole 60 of the paper cassette 32. As a result, the paper cassette 32 is prevented from being pulled out of the copying machine main body 14. Therefore, the user opens the lower right cover 24 of the copying machine body 14 to remove the jammed paper 34. For this reason, the problem that the paper 34 is torn off and remains in the copying machine main body 14 does not occur.

After locking the paper cassette 32 in step 91, it is determined in step 92 whether the jam clearing operation by opening the main body is completed. If a negative determination is made in step 92, the jam clearing operation has not been completed, so the process returns to step 90. If a positive determination is made in step 92, step 9 is executed.
Then, the process proceeds to step 3, and a message such as "You can continue copying" is displayed on the display unit 28, and the processing ends.

The determination as to whether or not the jam clearing operation by opening the main body is completed is performed, for example, as follows. In step 91, when the user removes the sheet cassette 32 and prevents the user from opening the lower right cover 24, the cover open / close sensor 74 detects this state. Next, when the user removes the jammed sheet 34 and then closes the lower right cover 24, this state is detected by the cover open / close sensor 74, and it is determined that the jam clearing operation has been completed.

The solenoid 50 of the lock means 48
Is demagnetized after being affirmed in step 92 as an example.

On the other hand, if the determination in step 89 is negative, that is, if there is no change in the output from the registration sensor 68, the sheet 34 has not been bitten by the conveying roller pair 64 (the sheet 34 has not been fed. (This indicates that the sheet 34 remains as it is in the sheet cassette 32 or that the sheet feeding operation has been performed slightly, but the sheet 34 has not reached the transport roller pair 64.) Therefore, it is determined that a misfeed jam has occurred. Therefore, a message such as "misfeed jam" is displayed on the display unit 28 in step 94. In this case, the user removes the paper cassette 32 from the copier body 14 without opening the lower right cover 24 in accordance with a message such as "misfeed jam".
The paper 34 is prepared. Therefore, unnecessary operations are not required, so that labor can be saved.

After the misfeed jam is displayed in step 94, it is determined in step 95 whether the jam clearing operation by removing the paper cassette is completed. If negative in step 95, the jam clearing operation has not been completed, so the process returns to step 94. If affirmative in step 95, the process proceeds to step 93, and a message such as "can continue copying" is displayed on the display unit 28. It ends.

The determination as to whether or not the jam clearing operation due to the detachment of the paper cassette is completed is performed, for example, as follows. The user inserts the paper cassette 32 into the copier body 1
When the paper cassette 32 is removed from the sheet cassette 32, the reed switch 46 becomes non-conductive, so that the removal state of the paper cassette 32 is detected.
Next, after the user prepares the paper 34 causing the misfeed jam, the user reloads the paper cassette 32 into the copying machine body 14, and this state is detected by the reed switch 46, and it is determined that the jam clearing operation is completed. I do.

As described above, in this embodiment, the paper feed roller 40
If the arrival of the sheet 34 is not detected by the registration sensor 68 when the Y time has elapsed from the start of the sheet feeding by the printer, it is determined that a jam has occurred, and then the conveying roller pair 64 is
The paper feeder is further operated for the time, and when the arrival of the paper 34 is detected by the registration sensor 68 when the X time has elapsed, it is determined whether a misfeed jam or a paper delay jam occurs. When it occurs, the type of the jam can be determined.

Further, when the result of the discrimination is a misfeed jam, the fact is displayed and the paper cassette 32 is attached and detached to perform the jam clearing operation. (Right lower cover 22
Open / close operation). Therefore, the trouble of the jam clear operation can be saved.

On the other hand, if the discrimination result is a paper delay jam, the locking means 48 prevents the paper cassette 32 from being pulled out of the copying machine main body 14, so that the user opens the right lower cover 22. A jam clear operation can be performed. Therefore, it is possible to prevent the sheet 34 from being torn when the jam clear operation is performed.

In this embodiment, the object of the present invention is the copying machine 10. However, the present invention is not limited to this.
The present invention may be applied to an image forming apparatus such as a facsimile machine.

In this embodiment, the lock means 48 including the solenoid 50, the lock lever 52, the tension coil spring 54, and the like is used. However, the structure of the lock means is not limited to this, and it is possible to prevent the paper cassette 32 from being pulled out. Any configuration that can be tolerated is applicable. For example, a stepping motor is used in place of the solenoid 50, and a rack that is moved by the rotation of the stepping motor is used in place of the lock lever 52. When a paper delay jam occurs, the rack is moved by a predetermined amount to thereby form the engagement hole 6
A configuration in which the rack is inserted and engaged with the rack 0 may be adopted.

Further, in this embodiment, the registration sensor 68 is used as the sheet detecting means, but the present invention is not limited to this, and a dedicated sensor may be separately provided.

Further, when the jam type determining method for an image forming apparatus according to the present invention is regarded as a jam type determining apparatus for an image forming apparatus, the following is obtained. (1) paper storage means for storing paper, paper supply means for feeding paper from the paper storage means, and conveyance means for conveying the paper fed from the paper supply means along a predetermined path;
A sheet detecting means provided at a position near the sheet storing means in the middle of the conveying path of the conveying means, and detecting the arrival of the sheet, and a control means for controlling the operation of the conveying means based on a signal from the sheet detecting means ( The controller 72 corresponds to this), and the control means determines whether the paper has not been detected by the paper detection means when a first predetermined time has elapsed from the start of paper supply by the paper supply means. Jam occurrence determination function for determining occurrence (steps 80 to
(Step 85 corresponds to this), and after the jam occurrence determination, the conveyance unit is further operated for a second predetermined time, and when the second predetermined time has elapsed, an error occurs depending on whether or not the arrival of the sheet is detected by the sheet detection unit. Jam type discriminating function for discriminating between feed jam and paper delay jam (steps 86 to 86)
Steps 90 and 94 correspond to this), and the jam type discriminating apparatus for an image forming apparatus.

When the jam clearing method for an image forming apparatus according to the present invention is regarded as a jam clearing apparatus for an image forming apparatus, the following (2) is obtained. (2) paper storage means for storing paper, paper supply means for feeding paper from the paper storage means, and conveyance means for conveying the paper fed from the paper supply means along a predetermined path;
A sheet detecting means for detecting arrival of a sheet and a sheet detecting means for detecting the arrival of a sheet are provided at a position on the way of the conveying path of the conveying means and near the sheet storing means. Locking means (lock means 48 corresponds to this) for preventing the means from being detached from the apparatus main body and allowing the paper storage means to be detached from the apparatus main body in the separated state, and conveying means based on a signal from the sheet detecting means. And control means for controlling the operation of the lock means. The control means determines whether or not the arrival of the paper is detected by the paper detection means when a first predetermined time has elapsed from the start of paper feeding by the paper feeding means. A jam occurrence determination function for determining the occurrence of a jam according to the above, and further operating the conveying means for a second predetermined time after the occurrence of the jam is determined, and the paper detection means when the second predetermined time has elapsed. A jam type discriminating function that determines whether a misfeed jam or a paper delay jam occurs depending on whether or not the arrival of paper has been detected. A jam clear operation specifying function (steps 91 to 93 and step 95) that enables the jam clear operation by enabling the lock means in the engaged state and permitting the opening of the apparatus main body when a paper delay jam occurs.
(Equivalent to the above). And a jam clearing device for an image forming apparatus.

[0051]

As described above, the jam type determining method for an image forming apparatus according to the first aspect of the present invention detects a sheet when a first predetermined time has elapsed from the start of sheet feeding by sheet feeding means. When the arrival of the sheet is not detected by the means, it is determined that a jam has occurred, and after the occurrence of the jam is determined, a second
The conveyance means is operated for a predetermined time, and when the second predetermined time has elapsed, whether the misfeed jam or the paper delay jam is determined based on whether or not the arrival of the paper is detected by the paper detection means. When a jam occurs in the vicinity of the sheet storage means, the present invention has an excellent effect that the type of the jam can be determined.

According to a second aspect of the present invention, there is provided a jam clearing method for an image forming apparatus according to the present invention, wherein the arrival of a sheet is detected by the sheet detecting means when a first predetermined time has elapsed from the start of sheet feeding by the sheet feeding means. Otherwise, it is determined that a paper jam has occurred, and after the paper jam has been determined, the conveying means is further operated for a second predetermined time, and when the paper detection means has detected the arrival of the paper when the second predetermined time has elapsed. A misfeed jam or a paper delay jam is determined based on the result. In the case of a misfeed jam, the paper storage unit is allowed to be separated from the apparatus main body to enable the jam clearing operation. The jam clear operation is enabled by preventing the paper storage means from being detached from the main body and allowing the main body to be opened to enable the jam clear operation. It has an excellent effect that it is possible to perform restore operations.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram schematically illustrating a jam type determination method according to an embodiment.

FIG. 2 is a perspective view showing the paper cassette shown in FIG.

FIG. 3 is a perspective view showing an appearance of the copying machine according to the embodiment.

FIG. 4 is a block diagram.

FIG. 5 is a flowchart showing control contents in the embodiment.

FIG. 6 is a schematic diagram showing a schematic configuration of a copying machine according to a conventional example.

FIG. 7 is an enlarged view showing a portion indicated by a broken line in FIG. 6 in an enlarged manner.

8 is a block diagram of a jam clear system used in the copying machine shown in FIG.

FIG. 9 is a schematic diagram showing a configuration of a main part of a copying machine according to another conventional example.

10 is a schematic configuration diagram of a jam clearing system used in the copying machine shown in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 copier (image forming apparatus) 14 copier main body (apparatus main body) 24 right lower cover 32 paper cassette (paper storing means) 34 paper 36 paper feeding means 48 locking means 64 transport roller pair (transporting means) 68 registration sensor (paper detection) Means) 72 Controller

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B65H 7/00

Claims (2)

(57) [Claims] 1. A paper storage means for storing paper, a paper supply means for feeding paper from the paper storage means, and a conveyance means for conveying paper fed from the paper supply means along a predetermined path. A sheet detecting means provided at a position near the sheet storage means in the middle of the conveying path of the conveying means, and detecting the arrival of the sheet. When the arrival of the sheet is not detected by the sheet detecting means when the first predetermined time has elapsed, it is determined that a jam has occurred. After the jam occurrence determination, the conveying means is operated for a second predetermined time, and the second predetermined time is determined. Determining whether a misfeed jam or a paper delay jam has occurred based on whether or not the arrival of the sheet has been detected by the sheet detection means when the time has elapsed. . 2. A paper storing means for storing paper, a paper feeding means for feeding paper from the paper storing means, and a conveying means for conveying the paper fed from the paper feeding means along a predetermined path. A sheet detecting means provided at a position near the sheet storage means in the middle of the conveying path of the conveying means, and detecting the arrival of the sheet. When the arrival of the sheet is not detected by the sheet detecting means when the first predetermined time has elapsed, it is determined that a jam has occurred. After the jam occurrence determination, the conveying means is operated for a second predetermined time, and the second predetermined time is determined. It is determined whether a misfeed jam or a paper delay jam has occurred based on whether the arrival of the sheet has been detected by the sheet detection means when the time has elapsed. Jam clearance operation is enabled by allowing removal from the main body, and in case of paper jam, jam clearance is prevented by preventing the paper storage means from leaving the main body and allowing the main body to be opened. A jam clearing method for an image forming apparatus, which enables an operation.