JPH09304977A - Document transport device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of a jam and breakage of a folding document by providing a document transport inhibiting means for inhibiting a folding document from being transported to a document placing table according to the discrimination result of a folding document discriminating means. SOLUTION: A folding document discriminating sensor 32 for discriminating a folding part 31a of a folding document 31 is disposed in front of a document call-in roller 4. The folding part 31a of the folding document 31 is thicker than the unfolding part by the folding amount to produce a difference A (about 2mm) in level. An actuator 32a of the folding discriminating sensor 32 disposed in front of the document call-in roller 4 is pushed by the difference A in level of folding, so that a signal of the folding discriminating sensor 32 is ON. In response to the signal, a CPU stops transporting a document set in a document transport device, and gives a warning to prevent breakage of the document.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document feeder for use in a copying machine or the like that automatically conveys a plurality of documents placed on a document feeder to a document holder for reading a document. is there.

[0002]

2. Description of the Related Art A conventional document conveying apparatus automatically conveys a plurality of documents placed on a document conveying table to a document placing table such as a copying machine which automatically reads the documents one by one. It was

In such a conventional document conveying apparatus, even when a plurality of originals containing folded originals are conveyed, automatic conveyance of originals is performed on the assumption that no folded originals are mixed. I was going.

[0004]

In the above-described document feeder, when a folded document is mixed in a plurality of documents to be transported, a jam occurs or the folded document is damaged by the transportation of the folded document. There was a risk of doing it.

It is an object of the present invention to prevent jamming and damage to a folded original by determining whether the original is a folded original and prohibiting the folded original from being conveyed to the original placing table. It was done.

[0006]

In order to achieve the above object, a document feeder according to a first aspect of the present invention is a document feeder for feeding a document placed on a document feeding table to a document placing table for reading a document. In the apparatus, a folding document discriminating means for discriminating whether or not the document is a folding document, and a document conveyance prohibiting means for prohibiting the conveyance of the folded document to the document mounting table based on the discrimination result by the folding document discriminating means. Is equipped with. With the above configuration, when a folded original is conveyed, the folded original is discriminated and the conveyance of the original to the original placing table is prohibited to prevent jamming and damage to the folded original.

In the original conveying apparatus according to the present invention, the folded original discriminating means includes a moving body that moves when the folded portion of the folded original abuts on it, and a discriminating section that detects the movement of the moving body and discriminates the folded original. In addition, a concave portion for bending the original at the time of calling the original is provided at a portion of the original feeding table which is brought into contact with the original calling roller. With the above configuration, when a folded original is conveyed, the unfolded portion of the original is curved to form a gap between the folded original and the folded portion of the original, and the folded original can be reliably identified. Is possible.

According to another aspect of the present invention, there is provided a document feeding device, which is provided with a control means for controlling the document feeding speed during a predetermined distance for feeding the document at a low speed. With the above configuration, damage to the folded portion of the folded document is prevented.

According to another aspect of the present invention, there are provided a plurality of the folded original discriminating means in a direction orthogonal to the original conveying direction. With the above configuration, the folded portion of the folded original can be surely detected, and erroneous determination due to the wrinkle of the original can be surely prevented.

According to a fifth aspect of the present invention, in the original conveying apparatus, the folded original discriminating means detects the movement of the original, and the movement of the original is not detected by the original movement detecting section when the original is conveyed. Sometimes it comprises a discriminating section for discriminating that the original is a folded document. With the above configuration, it is possible to detect the discrimination of a folded document at the same time when the document starts to be conveyed.

According to a sixth aspect of the present invention, there is provided a document feeding device, which is provided with air blowing means for blowing air onto the surface of the document being fed. With the above configuration, a gap is created between the unfolded portion and the folded portion of the folded original, and it is possible to reliably determine the folded original.

According to a seventh aspect of the present invention, there is provided a document feeding device, which is provided with a document pressing means for lightly contacting the rear end of the conveyed document and pressing the rear end of the document. With the above configuration, when transporting a folded document, it is possible to raise the tip of the folded part upwards to make a larger gap between the unfolded part and the folded part of the folded document, and distinguish the folded document. It is possible to reliably perform.

[0013]

1 is a sectional view of an image forming apparatus in this embodiment. After the original document is set on the original document conveying device 2 provided on the original document table 1 made of transparent hard glass and the original document is detected by the original document detection sensor 3,
When the operator presses the print switch arranged on the operation panel, the copying machine body starts the copying operation.

When the copying operation is started, the original placed on the original feeding device 2 is read by the original feeding roller 4, the original feeding roller 5, the original separating roller 6, the original registration roller 7,
Only one sheet is transported by the document transport belt 8 to the document operation start position on the document table 1.

When the original is conveyed, the irradiation lamp 9 arranged inside the irradiation lamp unit is turned on to illuminate the original. The reflected light is the first mirror 1 in the irradiation lamp unit.
0, the second mirror 11 and the third mirror 1 in the optical unit
2, the lens 17, the fourth mirror 14, the fifth mirror 15, and the sixth mirror 16 irradiate the photosensitive member 17 rotatably attached.

The irradiation lamp unit moves in the operating direction,
When the photoconductor 17 rotates in the clockwise direction, the original image is irradiated on the photoconductor 17. When the document scanning is completed, the document on the document table 1 is discharged by the document transport belt 8, the document reversing roller 18, and the document discharge roller 19.

During the above-mentioned operation, the copy sheet is fed by the sheet invoking roller 20, the sheet conveying roller 21, and the sheet separating plate 22.
Thus, only one sheet is fed / conveyed. After the sheet passes through the pre-registration sensor 23, the sheet conveyance is stopped when a predetermined time has passed, and the registration roller 24 corrects the oblique feeding of the sheet. After that, the registration rollers 24 are rotated in synchronization with the scanning timing of the document on the document table 1, and the sheet is conveyed.

On the other hand, in the photoconductor 17, the photoconductor 17 is uniformly charged by the corona discharge of the charging device 25, and thereafter,
By irradiating the reflected light of the document, the photoconductor 17
An electrostatic latent image is formed on it. This electrostatic latent image is visualized by the developing tank and transferred to the copy paper by the transfer device 26.

The developer remaining on the photoconductor 17 is cleaned by the cleaner 27, and the charge on the photoconductor 17 is removed by the static elimination light from the static eliminator 28. The copy paper on which the image is transferred by the transfer device 26 is the photoconductor 17
The image is peeled off by a peeling claw 29 which is arranged so as to be able to come into contact with and separated from the sheet.

FIG. 2 and FIG. 3 show a first embodiment of a document feeding device equipped with a folding discrimination sensor for discriminating a folded document.

Document 31 folded in the document feeder
When the copying operation is started, the folded original 31 is folded into the original feeding roller 4, the original feeding roller 5, the original separating roller 6, the original registration roller 7,
Although the original conveying belt 8 conveys the folded original 31 to the original scanning start position on the original placing table 1, a misfeed occurs while the folded original 31 is conveyed to the original scanning start position on the original placing table 1. Therefore, the folding original 3
The folding discrimination sensor 32 for discriminating the folded portion 31 a of No. 1 is arranged in front of the original document feeding roller 4.

In the folding determination sensor 32, the tip of the actuator 32a with which the folding portion 31a of the folded original 31 comes into contact causes the original 3 when the original 31 is automatically fed.
0.5 to 1.5 mm from the document transport table 33 that guides 1
It is arranged so that it becomes the height of.

Folding portion 31a of folding original 31
The original 31 from the unfolded portion 31b.
A step A (about 2 mm) is made thicker by the amount of folding. At the folding step A, the original document introduction roller 4
By pushing up the actuator 32a of the folding determination sensor 32 arranged in front of, the light-shielding portion of the actuator 32a that blocks the light from the light emitting diode of the photo sensor 32b in the folding determination sensor 32 moves. Phototransistor turns on by receiving light from the light emitting diode
Then, the signal of the folding determination sensor 32 is turned on.

By this signal, the CPU (central processing unit)
When the original set in the original feeder is stopped by the transportation, the warning message "The folded original is set on the original table. Please check the original." Is displayed. Prevent damage.

FIG. 4 and FIG. 5 show a second embodiment of the document feeding device provided with a folding discrimination sensor for discriminating a folded document. From both ends to the portion of the document feeding table 33 where the document feeding roller 4 contacts. A concave portion 33a is provided by curving downward to the central portion.

Document 31 folded in the document feeder
When is set, when the copy operation is started,
The folded original 31 is called by the original taking-in roller 4, but the original conveying table 33 that is in contact with the original taking-in roller 4 and the original 31 has a recess 33 a formed therein.
When the document-introducing roller 4 is brought into pressure contact with the document 31, the document 31 is curved by the recess 33a in a direction perpendicular to the conveying direction.

Due to this curving, a step B is generated in a normal folded original in an abnormal manner in the unfolded portion and the folded portion 31a. At the step B, the folding portion 31a arranged in front of the original document ingesting roller 4 is pushed up by the actuator 32a of the folding determination sensor 32 to block light from the light emitting diode of the photo sensor 32b in the folding determination sensor 32. Since the light-shielding portion of the actuator moves, the folding portion 31a can be more accurately discriminated, and the phototransistor of this photosensor 32b is turned on upon receiving the light from the light emitting diode, and the signal of the folding discrimination sensor 32 is transmitted. Turns on.

By this signal, the CPU (central processing unit)
The document set in the document feeder is stopped when it is stopped, and a warning message "A folded document is set on the document table. Please review the document." Is displayed and the document is damaged. Prevent.

FIG. 6 and FIG. 7 show a third embodiment of the document feeding device provided with a folding discrimination sensor for discriminating a folded document.

Document 31 folded by the document feeder
When the copying operation is started, the folded original 31 is conveyed by the original document intake roller 4, and the folding portion 31a has the folding determination sensor 3
The second actuator 32a is pushed up and passed.

When the folding discrimination sensor 32 discriminates the point where the folding portion 31a passes through the actuator 32a of the folding discrimination sensor 32, the signal of the folding discrimination sensor 32 is turned on.

By this signal, the CPU (central processing unit)
By stopping the rotation of the document feeding roller 4 and the document feeding roller 5 in the document feeding device, the folding portion 31a
In addition to reducing the impact damage of the document, it also prevents the document from being damaged by displaying a warning message "A folded document is set on the document table. Please review the document."

FIG. 8 to FIG. 12 show a fourth embodiment of the document feeding apparatus to which a non-contact type folding determination sensor for discriminating a folded document is attached.

The non-contact type folding determination sensor mounted in front of the original call-in roller 4 determines the folded portion of the original by the reflection type position determination sensor 34 based on the waveform reflected from the original surface.

When the folded original 31 is set, the waveform H ₀ of the output voltage of the reflection type position determination sensor 34 in the unfolded portion fluctuates within a constant width in the vicinity of the voltage value V _0. When 31 is conveyed by the document introduction roller 4 and the folding part 31a of the folded document 31 passes through the reflection type position detection sensor 34, the waveform Ha of the output voltage of the reflection type position detection sensor 34 is changed by the step A of the folding part 31a. Voltage value Va (V ₀
It fluctuates with a constant width in the vicinity of <Va).

In this way, the reflection type position detection sensor 34
Since the voltage value V of the waveform H of the output voltage is different between the unfolded portion and the folded portion 31a, the average value of the waveform H, that is, the voltage value V is set to the CPU (central processing unit).
The original is determined to be a folded and folded original by recognizing with, and the feeding of the original set in the original feeding device is stopped, and "Folded original is set on the original table. Please review. "To prevent the original from being damaged.

In FIG. 11, a distance measuring sensor (Position Sensitive) is used as the reflection type position detecting sensor 34.
An example using a diode (PSD sensor) will be described. The distance measuring sensor uses reflection of light.
The light emitted from D is reflected by the object, that is, the original and enters the distance measuring sensor. At this time, the output of the distance measuring sensor is shown in FIG. 12 depending on the distance between the original and the distance measuring sensor. Since it changes as shown, the distance to the original is measured with this output voltage to determine whether or not the original is a folded original.

That is, the distance between the non-folded portion of the folded document and the folding portion 31 and the distance measuring sensor differs by the amount of folding the document (folding portion 31.
Since a is closer to the distance measuring sensor), the output voltage of the distance measuring sensor is different and it is determined whether the original is a folded document.

FIG. 13 and FIG. 14 show a fifth embodiment of a document feeding device having a plurality of folding determination sensors for determining a folded document, and two folding determination sensors 32 in the direction perpendicular to the document feeding direction. It is provided.

Document 31 folded in the document feeder
When is set, when the copy operation is started,
The folded original 31 is called by the original drawing roller 4.

Two folding determination sensors 32 arranged in front of the original document ingesting roller 4 are provided in a direction perpendicular to the original conveying direction, and the conveyed folding original 31 is at the step A of the folding portion 31. The two push up the actuator 32a of the folding determination sensor 32 almost at the same time, and the light blocking portion of the actuator that blocks the light from the light emitting diode of the photo sensor 32b in the folding determination sensor 32 moves, and the phototransistor of the photo sensor 32b moves. The light from the light emitting diode is received and turned on, and the signals of the two folding discrimination sensors 32 are simultaneously turned on.

In response to the signals from the two folding discrimination sensors 32, the CPU (central processing unit) stops the transportation of the document set on the document transport device, and at the same time, "the folded document is set on the document mounting table. Please review the original. "To prevent damage to the original.

On the other hand, if the original is not a folded original but an ordinary original with wrinkles, the folding determination sensor 32 may turn on due to wrinkles.
At this time, the two folding discrimination sensors 32 are simultaneously turned on.
N does not occur, and erroneous discrimination due to wrinkles can be prevented.

FIG. 15 to FIG. 17 show a sixth embodiment of the document feeding apparatus having a plurality of folding discrimination sensors for discriminating folded documents.

Document 31 folded in the document feeder
When is set, when the copy operation is started,
Since the entire document surface is transported at a constant transport speed, the swing member 32c, which is lightly pressed against the surface of the folding portion 31a and is swingable, swings (lifts) in the document transport direction.
The original is conveyed to the scanning start position of the original placing table 1,
In the case of the folded original 31, the folding portion 31a receives the conveyance resistance by the swinging member 32c, so that the force for opening the folding acts and the swinging member 32 is opened during the opening.
The swing of c is stopped or the swing operation becomes slow.

The detection time of this normal document detection (the swing member 3
The detection time T ₂ is later at the folded original 31 o'clock than the time 2 t for detecting the swing of 2 c) T ₁ , so this time difference signal is recognized by the CPU (central processing unit) and is longer than the normal detection time T _1. When the swing of the swinging member 32c is detected late, it is determined that the document being conveyed is the folded document 31, the CPU stops the conveyance of the document set in the document conveying device, and A folded document is set. Please review the document. "To prevent damage to the document.

In the folding discrimination sensor 32, since the swinging member 32c is lightly pressed against the original from above, the folding discrimination sensor 32 can be easily attached as compared with the actuator 32a of the first embodiment. Can be Moreover, in the case of using the actuator 32a, it is determined whether or not the original is the folded original 31 when the original is conveyed to some extent, and the actuator 32a hits the original being conveyed, which may impose a burden on the original. However, when the swinging member 32c is brought into light contact with the original from above, the load on the original is reduced because the original is in contact with the original before the conveyance of the original is started.

FIG. 18 and FIG. 19 show a seventh embodiment of the document feeding device equipped with a folding discrimination sensor for discriminating a folded document, which is 1/4 of the maximum document size (A3) for folding shown in FIG. Position and the minimum document size for folding (B
The folding determination sensor 32 is attached between the position and a position corresponding to a distance of 1/2 of 4).

As shown in FIG. 19, an original is first folded in half at a half position, and the folded portion is folded back in half. Therefore, the maximum original size for folding is A3 and the minimum size is A3. Document size is B
It becomes 4.

Therefore, the folding determination sensor 32 is set to A
By providing the positions corresponding to ¼ of the three sizes and ½ of the B4 size, it is possible to surely determine the folding of the document of the minimum size to the maximum size in which folding is performed.

FIG. 20 and FIG. 21 show an eighth embodiment of the document feeding device provided with a folding discrimination sensor for discriminating a folded document.

The folding determination sensor 32 is provided with a rubber roller 32d which comes into contact with the original document and rotates from above the original document, and a rotary disk 32e is coaxially attached to the rubber roller 32d. The rotating disk 32e is provided with holes at equal intervals, and the rubber roller 32d rotates at a constant speed due to the frictional resistance with the surface of the original.

When the rubber roller 32d rotates, the rotary disc 32e also rotates at the same time, and the phototransistor of the photosensor receives light from the light emitting diode as ON and OFF through the hole provided in the rotary disc 32e. The ON / OFF signal timing is read by the CPU, and when it is correlated with the conveyance speed, the original is conveyed to the scanning start position of the original placing table.

In the case of the folded original 31, the folding portion 31a tries to open the fold because the folding portion 31a receives the conveyance resistance due to the frictional resistance of the rubber roller 32d. During this time. The rotation of the rubber roller 32d is stopped or slowed down, and the ON / OFF signal received by the photo sensor is ON or O.
Since only the FF or the ON / OFF cycle becomes longer than the cycle of the detection signal at the time of normal document conveyance (the ON / OFF frequency decreases), in this case the folded document 3
If the CPU judges that it is 1, the CPU stops the feeding of the original set in the original feeding device, and at the same time displays the warning "A folded original has been set. Please check the original." Prevent.

FIGS. 22 and 23 show a ninth embodiment of the document feeding apparatus equipped with a folding discrimination sensor for discriminating a folded document. A fan 35 is provided, and the wind from the fan 35 is provided downstream of the document feeding direction. A guide 36 is provided for guiding the surface of the original from the side to the upstream side.

When the folded original 31 is set in the original conveying device, the print switch is pressed to start the copying operation, and at the same time, the CPU rotates the fan 35. The wind from the fan 35 passes through the guide 36 and is blown from the front end (downstream side in the transport direction) of the folded original 31 toward the rear end (upstream side in the transport direction).

When the folded original 31 is conveyed by the original feeding roller 4, the wind from the fan 35 is blown onto the surface of the folded original 31, so that the folded portion 31a is lifted, and the folded portion 31a is not folded. A large step A with the folded portion 31a occurs. Since the folded portion 31a is discriminated by the step A that greatly occurs, it is possible to surely discriminate the folded original 31. Therefore, if this folding is discriminated, the CPU
At the same time as stopping the feeding of the document set in the document feeder, "Folded document is set."
Please review the manuscript. The warning is displayed to prevent the original from being damaged.

FIG. 24 and FIG. 25 show a tenth embodiment of a document feeding device provided with a folding discrimination sensor for discriminating a folded document, in which a document feeding roller 5 is provided slidably up and down. 5 is provided with a spring 37 that constantly urges the document conveying roller 5 downward, and an operating body 38 that moves the document conveying roller 5 upward against the urging force of the spring 37 to release the pressure contact of the document conveying roller 5 is provided. A solenoid 39 for releasing the original pressure contact is provided for driving.

Folding portion 31a of folding original 31
3 of the folding determination sensor 32 by
When 2a is lifted and the signal of the folding determination sensor 32 is turned on, the CPU outputs a signal to stop the conveyance of the document, and the document conveyance roller 5 is stopped.

Next, a signal is output from the CP to release the pressure contact of the document conveyance roller 5, the document pressure contact release solenoid 39 is turned on, and the operation body 38 is operated to move the document conveyance roller 5 upward to move the document. The pressure contact of the document by the transport roller 5 is released.

By releasing the pressure contact of the original conveying roller 5, the conveying pressure of the folded original 31 during the conveyance is released, and the folded original 31 can be easily pulled out to prevent the original from being damaged. be able to.

When the signal from the folding determination sensor 32 is turned on, the CPU reverses the drive motor 40 for rotating the document feeding roller 5, whereby the document feeding roller 5 is rotated in the reverse direction and the folded document 31 is returned to its original position. By returning to the original position, damage to the original is prevented.

FIG. 28 and FIG. 29 show an eleventh embodiment of a document feeding device equipped with a folding discrimination sensor for discriminating a folded document. The document placed on the document feeding table 33 at the rear of the document feeding table 33 is shown. A document pressing body 41 (rubber plate) which is lightly pressed and pressed from above is provided at the rear end, and a light receiving element (or a light emitting element) 42 is provided adjacent to the document pressing body 41, and a conveying direction facing the light receiving element 42. A light emitting element (or light receiving element) 43 is provided on the downstream side.

When the folding original 31 is set in the original feeding device, when the copying operation is started, the folding original 31 is fed by the original feeding roller 4. At this time, since the original pressing body 41 is lightly pressed against the folding portion 31a (the rear end of the original), the original pressing body 41 gives a conveyance resistance, so that the rear end of the folding portion 31a receives the conveyance resistance and moves. Instead, the tip of the folded portion 31a is lifted, and the folded portion 31a in this state is
The light from the light emitting element 43 is blocked, and the light from the light emitting element 43 does not reach the light receiving element 42. By detecting this, it is determined that the original is a folded original, and the CPU sets the original set in the original feeding device. The document is prevented from being damaged by stopping the transportation of the document and displaying the warning "A folded document is set. Please review the document."

The twelfth embodiment of the document conveying apparatus equipped with the folding discrimination sensor for discriminating the folded document will be described. The image forming operation is performed at the time when the drum cleaning is performed within a predetermined time after the operation is started. In the CPU that waits and does not feed copy paper and determines whether or not a detection signal for a folded document is generated,
Only when the folded original is not detected within a predetermined time, the normal image forming operation, paper feeding, transfer, fixing, etc. are performed and the copying operation is completed.

On the other hand, after the copying operation is started, the CPU
If a folded original is detected within a predetermined time, the original feeding is stopped and the copying operation is stopped as it is because the image forming operation and the feeding of copy paper are not performed.

[0067]

According to the document feeder of the first aspect of the present invention, a folded document discriminating means for discriminating whether or not the document is a folded document and a folding document discriminated based on the discrimination result by the folded document discriminating means. Since a document conveyance prohibiting means for prohibiting conveyance to the document placing table is provided, when a folded document is conveyed, the folded document is discriminated and the conveyance of the document to the document placing table is prohibited to prevent jams and jams. It is possible to prevent the folding original from being damaged.

In the original conveying apparatus according to the present invention, the folded original discriminating means includes a moving body which the folding portion of the folded original abuts and moves, and a discriminating portion which detects the movement of the moving body and discriminates the folded original. When the folded original is conveyed, the unfolded portion of the original is curved when the folded original is conveyed. By forming a gap between the folded document and the folding portion, the folded document can be surely discriminated and erroneous discrimination can be prevented.

Since the document feeder according to claim 3 is provided with the control means for controlling the document feeding speed at a low speed for the predetermined distance of the document feeding, the folded portion of the folded document is prevented from being damaged. ing.

In the document feeder according to the present invention, since a plurality of the folded document discriminating means are provided in the direction orthogonal to the document conveying direction, the folded portion of the folded document can be surely detected, and the document can be surely detected. Misjudgment due to wrinkles can be reliably prevented.

In the document feeder according to the present invention, the folded document discriminating means detects the movement of the document and the movement of the document is not detected by the document movement detector when the document is conveyed. Since it is composed of a discriminating unit which discriminates that the document is a folded document, it is possible to detect the discrimination of the folded document at the same time when the document starts to be conveyed, and it is possible to discriminate the folded document early.

In the document feeder according to the sixth aspect, since the surface of the document to be conveyed is provided with air blowing means for blowing air,
A gap is created between the unfolded portion and the folded portion of the folded document, and the folded document can be reliably identified.

In the document feeder according to the seventh aspect of the present invention, since the document pressing means for pressing the rear end of the original to be pressed by lightly contacting the rear end of the original to be conveyed is provided, when the folded original is conveyed,
By lifting the tip of the folded portion upward, it is possible to make a larger gap between the unfolded portion and the folded portion of the folded original, and it is possible to reliably determine the folded original.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a copying machine using a document feeder of the present invention.

FIG. 2 is a perspective view showing a first embodiment of a document feeder of the present invention.

3 is a cross-sectional view of FIG.

FIG. 4 is a perspective view showing a second embodiment of the document feeder of the present invention.

FIG. 5 is a sectional view of FIG. 4;

FIG. 6 is a cross-sectional view showing a state before detecting a folded document in the third embodiment of the document feeder of the present invention.

FIG. 7 is a cross-sectional view showing a state at the time of detecting a folded document in the third embodiment of the document feeder of the present invention.

FIG. 8 is a perspective view showing a fourth embodiment of the document feeder of the present invention.

FIG. 9 is a sectional view of FIG. 8;

10A is a waveform diagram of the output of the folding determination sensor of FIG. 8, and FIG. 10B is an explanatory diagram showing the relationship between the folding determination sensor and the document.

11 is an electrical block diagram showing the folding determination sensor of FIG.

12 is a characteristic diagram showing an output voltage of the folding determination sensor of FIG.

FIG. 13 is a perspective view showing a fifth embodiment of the document feeder of the present invention.

14 is a cross-sectional view of FIG.

FIG. 15 is a perspective view showing a sixth embodiment of the document feeder of the present invention.

16 is a cross-sectional view of FIG.

17A is an explanatory diagram showing the relationship between the output signal of the folding discrimination sensor of FIG. 15 and the conveyance of a document during normal document conveyance, and FIG. 17B is the folding discrimination sensor of FIG. 15 during conveyance of a folded document. FIG. 6 is an explanatory diagram showing a relationship between an output signal and conveyance of a document.

FIG. 18 is a cross-sectional view showing a seventh embodiment of the document feeder of the present invention.

FIG. 19 is an explanatory diagram showing the relationship between the attachment position of the folding determination sensor of FIG. 18 and the size of a document.

FIG. 20 is a perspective view showing an eighth embodiment of the document feeder of the present invention.

FIG. 21 is a sectional view of FIG. 20;

FIG. 22 is a perspective view showing a ninth embodiment of the document feeder of the present invention.

FIG. 23 is a sectional view of FIG. 22;

FIG. 24 is a sectional view showing a tenth embodiment of a document feeder of the present invention.

FIG. 25 is a perspective view showing the vicinity of the document feeding roller 5 of FIG. 24.

FIG. 26 is a cross-sectional view showing the document conveying roller 5 before detection of a folded document.

FIG. 27 is a cross-sectional view showing the document conveying roller 5 after detection of a folded document.

FIG. 28 is a perspective view showing an eleventh embodiment of the document feeder of the present invention.

29 is a cross-sectional view of FIG. 28.

[Explanation of symbols]

 1 Document Placement Table 2 Document Feeding Device 4 Document Calling Roller 5 Document Feeding Roller 6 Document Separation Roller 31 Folding Document 32 Folding Discrimination Sensor 32a Actuator 32b Photo Sensor 33 Document Feeding Plate

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Junichi Kajiwara 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Within Sharp Corporation (72) Inventor Michiaki Nishimura 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Incorporated (72) Inventor Shinji Kato 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Within Sharp Corporation (72) Minoru Tomi 22-22, Nagaike-cho, Abeno-ku, Osaka-shi, Osaka, Osaka Within

Claims (7)

[Claims] 1. A document transport apparatus for transporting a document placed on a document transport table to a document table for reading a document, and folding document determination means for determining whether or not the document is a folded document. An original document conveyance device, comprising: an original document conveyance prohibiting unit that prohibits conveyance of a folded original document to the original document placement table based on a result of discrimination by the folded original document discrimination unit. 2. The folding original discriminating means comprises a moving body which a folding portion of the folding original abuts and moves, and a discriminating portion which detects the movement of the moving body and discriminates the folding original. 2. The document feeding device according to claim 1, wherein a concave portion for bending the document when the document is called is provided in a portion where the document calling roller comes into contact. 3. The document conveying apparatus according to claim 1, further comprising control means for controlling the document conveying speed during a predetermined distance for conveying the document at a low speed. 4. The document conveying apparatus according to claim 1, wherein a plurality of the folded document discriminating means are provided in a direction orthogonal to the document conveying direction. 5. The folded document discriminating means discriminates that the document is a folded document when a document movement detection unit for detecting movement of the document and a movement of the document is not detected by the document movement detection unit during conveyance of the document. The document feeder according to claim 1, further comprising: 6. The document feeder according to claim 1, further comprising a blowing unit for blowing air on the surface of the conveyed document. 7. The document feeder according to claim 1, further comprising a document pressing unit which presses the trailing end of the transported document and presses the trailing end of the document.