JPH09244307A - Automatic document feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic document feeder capable of efficiently removing a residing document without damaging. SOLUTION: A detecting sensor 10 containing a pressure element is used not only to detect whether a residing document S exists or not on a platen glass 5 but also to judge whether the residing document S, if existing, can be automatically discharged or not by an automatic document feeder 6. If the document S can be automatically discharged, a feeding belt 8 is operated to automatically discharge the residing document S and, only if it cannot be automatically discharged, an alarm sounds. The detecting sensor 10 is used to detect whether the residing document S exists or not on the platen glass 5 and, if the residing document S exists, the feeding belt 8 can driven for a preset time only to judge whether the residing document S can be automatically discharged or not by the automatic document feeder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic document feeder which is provided in an image forming apparatus such as an electrophotographic copying machine and which automatically supplies and discharges a document to be copied onto a platen glass. Is.

[0002]

2. Description of the Related Art As is well known, in an image forming apparatus such as an electrophotographic copying machine in recent years, a document to be copied is automatically supplied onto a platen glass, and after the image of the document is read, the platen is read. An automatic document feeder for discharging the document from the glass is provided.

In such an automatic document feeder, for example, the document on the platen glass cannot be correctly discharged, or the document is manually placed on the platen glass without using the automatic supply / discharge function of the automatic document feeder. Then, if there is a document remaining on the platen glass (hereinafter, referred to as “residual document”), if the document is supplied by the automatic document feeder as it is without removing the remaining document from the platen glass, There is a problem that the remaining original and the newly supplied original collide with each other, and the original is broken or torn and damaged.

In order to solve such a problem, for example, when it is attempted to feed a document by an automatic document feeder, various sensors detect that there is a document remaining on the platen glass. When the presence is detected, a warning is issued (Japanese Patent Laid-Open Nos. 53-132350 and 59-29239), or the operation of the automatic document feeder is stopped (Japanese Patent Laid-Open No. 64-59227).
Japanese Patent Laid-Open No. 60-115927).

Further, when an automatic document feeder tries to feed a document, when various sensors detect that there is a document remaining on the platen glass, it has a function of automatically discharging the document remaining. A configuration technique has also been proposed (Japanese Patent Laid-Open No. 64-61740, Japanese Patent Laid-Open No. 2-2313).
No. 2).

[0006]

However, the conventional automatic document feeder as described above has the following problems. First, in the technology that issues a warning or stops the operation of the automatic document feeder when it detects that there is a residual document, the operation is interrupted when the residual document is removed from the platen glass. However, the operability is poor because the automatic document feeding operation must be resumed after the paper is manually removed. Also,
With the technology that automatically ejects the remaining originals, if the remaining originals are, for example, thick paper, or notebooks, books, or clips or staples, these residual originals are automatically If the paper is forcibly ejected, there is a problem that the original is jammed or the original is damaged.

The present invention has been made in consideration of the above points, and it is an object of the present invention to provide an automatic document feeder capable of efficiently removing a residual document without damaging the document. To do.

[0008]

The invention according to claim 1 is
An automatic document feeder provided in the image forming apparatus,
A platen glass on which the original document is placed to read an image of the original document, a supply unit that supplies the original document onto the platen glass, an original document detection unit that detects the thickness of the original document on the platen glass, and the original document Discharge means for discharging from the platen glass; determination means for determining whether or not the document on the platen glass can be discharged by the discharge means based on the detection result of the document detecting means; Is provided on the platen glass, and a warning means for warning that it is present on the platen glass, and a control means for controlling the operation of the discharging means and the warning means based on the determination result by the determination means. Detecting the thickness of the document on the platen glass by the document detection means,
When the determination means determines that this is a thickness that can be discharged by the discharge means, the discharge means discharges the original from the platen glass, and the detected thickness of the original cannot be discharged by the discharge means. When the determination means determines that the thickness is large, the warning means controls to warn that the document is present on the platen glass.

According to a second aspect of the present invention, there is provided an automatic document feeder provided in an image forming apparatus, wherein a platen glass on which the document is placed for reading an image of the document, and the document on the platen glass. Supply means for supplying, document detecting means for detecting a document on the platen glass, discharge means for discharging the document from the platen glass,
Based on the detection result of the document detection unit, a determination unit for determining whether the document on the platen glass can be discharged by the discharge unit, and a warning that the document is present on the platen glass Warning means and control means for controlling the operation of the discharging means and the warning means based on the judgment result of the judging means, wherein the controlling means drives the discharging means for a predetermined time, When the document on the platen glass is detected by the document detecting means and the document is moved by a predetermined size or more,
The determination unit determines that the document can be discharged by the discharge unit, controls the discharge unit to discharge the document from the platen glass, and the document moves only within a predetermined size. In this case, the determination means determines that the document cannot be discharged by the discharge means, and the warning means controls to warn that the document is present on the platen glass. It is characterized by that.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION First to third embodiments of an automatic document feeder according to the present invention will be described below with reference to FIGS.

(1) First Embodiment First, an example in which a piezoelectric element, for example, is used as the document detecting means for detecting the remaining document on the platen glass will be described.

In FIG. 1, reference numeral 1 is an electrophotographic copying machine (image forming apparatus), 2 is a copying machine main body for copying an image of an original, 3 is an original table on which an original to be copied is placed, Reference numeral 4 denotes a document cover that holds the document on the document table 3 by pressing it from above.

As shown in FIG. 2, the platen glass 5 is provided on the upper surface of the document table 3, and the document is set on the platen glass 5 with the image facing downward. . A scanner (not shown) is arranged below the platen glass 5, and the image of the original is read by this scanner.

As shown in FIG. 1, the manuscript cover 4 is hinged to the rear end of the copying machine main body 2 and can be opened and closed. The document cover 4 has a built-in automatic document feeder 6 that automatically feeds a document onto the platen glass 5 and discharges it onto the document cover 4 after copying.

The automatic document feeder 6 is provided with a document tray 7 on which a document is set in a predetermined upward or downward direction. Further, as shown in FIG. 2, the automatic document feeder 6 is provided with an endless feed belt (feed means, discharge means) 8, and the feed belt 8 is provided with a drive mechanism (not shown) such as a motor. The originals accommodated in the original tray 7 are rotated one by one by driving the platen glass 5 one by one.
It is designed to be sent up and ejected after copying.

In this copying machine 1, the original cover 4 is opened and the original is directly placed on the platen glass 5, and then the original cover 4 is inserted.
There is a "manual mode" in which the document is closed and the document is pressed, and an "automatic document feed mode" in which the document is set on the document tray 7 of the automatic document feeder 6 and is automatically fed / discharged. In the automatic document feeding mode, a plurality of documents can be continuously supplied / discharged.

In such an automatic document feeder 6, a detection sensor (original detection means) for detecting the residual document S on the platen glass 5 is provided on the back side of the feed belt 8.
10 are provided. A piezoelectric element is used for the detection sensor 10, and the platen glass 5 and the feed belt 8 are used.
The pressure that changes depending on the thickness of the remaining document S between the and is detected. Needless to say, the pressure becomes 0 (zero) if there is no residual document S between the platen glass 5 and the feed belt 8, and the thicker the residual document S is, the higher the pressure becomes.

As shown in FIG. 3, this detection sensor 10
Are connected to a CPU (determination means, control means) 12 via an amplifier circuit 11. The detection sensor 10 detects not only the presence or absence of the residual document S, but also the thickness of the residual document S when it is present. And CPU1
In No. 2, it is determined whether the thickness of the residual document S detected by the detection sensor 10 is within or outside the range of the thickness that can be discharged by the automatic document feeder 6 defined in advance. The operation of the automatic document feeder 6 is controlled.

Next, the copying machine 1 having the above structure.
A control method of the automatic document feeder 6 provided in the above will be described. As shown in the flowchart of FIG. 4, first, a sensor (not shown) detects whether the automatic document feeder 6 or the document cover 4 is closed (STEP 1).

When the automatic document feeder 6 is closed, after detecting that the document is set on the automatic document feeder 6, the detection sensor 10 detects the remaining original S on the platen glass 5 as follows. In this way (STEP
2). To this end, based on the pressure value detected by the detection sensor 10, when the pressure value is 0, the CPU 12 determines that there is no residual document S, and the JOB of the automatic feeding operation is started.
Let me do ART. If the detected pressure value is within the range of the thickness of the document that can be automatically discharged by the automatic document feeder 6, it is determined that the document can be automatically discharged, and the feed belt 8 is driven by the drive mechanism to remain. The document S is automatically ejected. On the other hand, when the detected pressure value is higher than the range of the thickness of the document that can be automatically discharged by the automatic document feeder 6, it is determined that the automatic discharge is impossible. In this case, various warning means such as voices or display lamps give a warning to the effect such as "There are documents that cannot be automatically ejected. Please remove them."

After the warning is issued, it is detected whether the automatic document feeder 6 is opened and then closed again (STEPs 3 and 4). This is to confirm whether or not the residual document S on the platen glass 5 is removed after opening the document cover 4 and removing it. After it is determined that the residual document S is removed in this manner, the ST
The process moves to EP2, and the remaining document S on the platen glass 5 is again detected.
Check again for

In the automatic document feeder 6 described above,
The platen glass 5 is provided with the detection sensor 10 including a pressure element.
Not only is the presence or absence of the above-described residual original S detected, but if there is a residual original S, it is determined whether the thickness of the residual original S can be automatically ejected by the automatic original feeding device 6, and the thickness is such that automatic ejection is possible. In this case, the feed belt 8 is actuated to operate the residual document S.
Is automatically ejected, and only when the thickness is such that it cannot be ejected automatically, a warning is issued and the residual document S is manually removed. As a result, even if there is a residual document S on the platen glass 5 when the automatic document feeder 6 attempts to automatically feed the document, if it can be automatically ejected, it is automatically ejected by utilizing the automatic function. Copying can be performed without interruption, and thus operability can be improved as compared with the related art. Moreover, it is determined that the remaining original S cannot be automatically ejected when the remaining original S is not only a thick paper, a notebook or a book bound like a book, but also a plurality of originals closed by clips or staples. Since the document is not automatically ejected, it is possible to prevent the document from being broken or damaged and being damaged.

(2) Second Embodiment Next, a second embodiment of the automatic document feeder according to the present invention will be described. In the following description, the basic configuration of the copying machine 1 is the same as that of the first embodiment, and therefore, the common components are designated by the same reference numerals and the description thereof is omitted.

As shown in FIG. 5A, the automatic document feeder 6 of the copying machine 1 includes a pair of, for example, light emitting and receiving elements for detecting the presence or absence of an original on the platen glass 5. A sensor (document detecting means) 20 is installed. Other than this, a reflective sensor, a piezoelectric element, or the like can be used as the detection sensor 20. When the document is set on the platen glass 5, the detection sensor 20 is installed at a position spaced from the end of the document by a predetermined dimension along the document feeding direction (the arrow direction in the drawing).

In the automatic document feeder 6 equipped with such a detection sensor 20, ST of the flowchart shown in FIG.
In EP2, a control circuit (judging means, control means) not shown controls the circuit as follows. First, the detection sensor 20 detects the presence or absence of the residual document S on the platen glass 5. If there is no remaining document S, the JOB of the automatic feeding operation of the automatic document feeder 6 is set to S.
TART.

If there is a residual document S, the feed belt 8 is driven by the driving mechanism for a predetermined time to feed the document on the platen glass 5, and then the detection sensor 2 is operated.
At 0, the presence or absence of the remaining document S is detected again. Then, FIG.
As shown in (b), the residual document S on the platen glass 5
However, when there is only one normal sheet, the residual document S moves by a dimension corresponding to the feed amount of the feed belt 8. Therefore, in this case, since the edge of the residual document S has passed the detection sensor 20, the detection sensor 20 does not detect the residual document S. In this way, the detection sensor 20
If the residual original S is not detected in step S1, the control circuit determines that the residual original S that can be automatically ejected is on the platen glass 5, and the feed belt 8 is driven by the drive mechanism to remove the residual original S.
Is automatically ejected.

Further, as shown in FIG. 5C, when the residual original S ₁ on the platen glass 5 is thicker and heavier than one normal sheet, the feed amount of the feed belt 8 is increased. without passing through the detection sensor 20 since the movement amount of residual document S is reduced relative to, the detection sensor 20 remaining document S ₁
Is detected. Similarly, as shown in FIG. 5D, when two or more remaining originals S ₂ on the platen glass 5 are overlapped or bound, only the uppermost original is fed by the feed belt. Since the document is moved by 8 and the document below it is not moved, the detection sensor 20 also detects the residual document S ₂ in this case. In this way, when the detection sensor 20 detects the remaining original S even after the feed belt 8 is driven for a predetermined time, in the control circuit, the original that cannot be automatically fed by the automatic document feeder 6 is on the platen glass 5. It is determined to exist, and a warning is issued. After that, as in the first embodiment, after confirming that the residual original S has been manually removed, the process proceeds to STEP 2.

In the automatic document feeder 6 described above,
Whether or not the residual original S on the platen glass 5 is detected by the detection sensor 20 and if the residual original S exists, whether the residual original S can be automatically discharged by the automatic original feeder 6 by driving the feed belt 8 for a predetermined time. If the original is a document that can be automatically ejected, the feed belt 8 is operated to automatically eject the remaining original S. If the original cannot be automatically ejected, a warning is issued and the remaining document S is manually ejected. The original S is removed. As a result, similar to the effect of the first embodiment, document jam due to document remaining is prevented, operability is improved as compared with the conventional one, and the document is prevented from being broken or damaged and damaged. can do.

(3) Third Embodiment Next, a third embodiment of the automatic document feeder according to the present invention will be described. Also in the following description, the basic configuration of the copying machine 1 is the same as that of the first embodiment, and therefore, the same reference numerals are given to common configurations and the description thereof is omitted.

As shown in FIG. 6A, the automatic document feeder 6 of the copying machine 1 is provided with a detection sensor (document detection means) 25 for detecting the size of the document on the platen glass 5. There is. The detection sensor 25 has a structure in which transparent electrodes are arranged on the platen glass 5 and electrodes are arranged below the original cover 4, or fluorescent whitening having a light absorption region and a light emission region on the lower surface of the platen glass 5. Various well-known ones such as a structure in which a white plate containing a material is arranged and a structure in which a line sensor is arranged can be adopted.

In the automatic document feeder 6 equipped with such a detection sensor 25, ST of the flow chart shown in FIG.
In EP2, similarly to the second embodiment, the control circuit (determination means, control means) (not shown) controls as follows. First, the detection sensor 2
At 5, the presence or absence of the residual document S on the platen glass 5 is detected. Then, if there is no remaining document S, the JOB of the automatic feeding operation of the automatic document feeder 6 is started.

If there is a remaining original S, the drive mechanism drives the feed belt 8 (see FIG. 2) for a predetermined time to perform the operation of feeding the original on the platen glass 5.
The detection sensor 25 detects again the presence or absence of the residual document S. Then, as shown in FIG. 6B, when the remaining original document S on the platen glass 5 is only one normal sheet, the remaining original document S has a size corresponding to the feed amount of the feed belt 8.
Is moved, and the size of the remaining original S detected by the detection sensor 25 is the same as the size detected before the movement.
In this case, the control circuit determines that the residual original S can be automatically ejected, and the feed belt 8 is driven by the drive mechanism to completely and automatically eject the residual original S.

On the other hand, as shown in FIG. 6 (c), when there are a plurality of remaining originals S ₃ on the platen glass 5, only the uppermost original is moved by the feed belt 8 and lower than that. Since the original document No. does not move, the size of the residual original document S detected by the detection sensor 25 becomes larger than the size detected before the movement. Further, as shown in FIG. 6D, when the remaining original S ₄ on the platen glass 5 is thicker and heavier than a normal original, the original is fed with respect to the feed amount of the feed belt 8. The amount of movement will decrease. Furthermore, FIG.
As shown in (e), the remaining original S on the platen glass 5
_{In the case where 5} is bound by a clip or a stapler, only the uppermost original is moved by the feed belt 8. Therefore, the detection sensor 25 determines that the size of the residual original S is smaller than the size detected before the movement. Also grows. As described above, after the feed belt 8 is driven for a predetermined time, the detection sensor 25 detects the position and size of the residual document S, and when the positional deviation amount is small or the size is large,
The control circuit determines that the residual original S that cannot be automatically fed by the automatic original feeder 6 exists on the platen glass 5, and issues a warning. After this, the first
Similar to the embodiment described above, after confirming that the residual document S has been manually removed, the process proceeds to STEP 2.

In the automatic document feeder 6 described above,
The detection sensor 25 detects the position and size on the platen glass 5, and if there is a residual document S, the feed belt 8 is driven for a predetermined time to determine whether or not the residual document S can be automatically discharged by the automatic document feeder 6. If the original is an automatically ejectable original, the feed belt 8 is operated to automatically eject the residual original S. If the original cannot be automatically ejected, a warning is issued and the residual original S is manually input. Is configured to be removed. As a result, similar to the effects of the first and second embodiments, document jam due to document remaining is prevented, operability is improved as compared with the conventional one, and the document is damaged by being bent or damaged. Can be prevented.

In the first to third embodiments described above, when the document is set on the automatic document feeder 6, the process of detecting the residual document S is performed in STEP2. As shown, the process of detecting the residual document S (STE
P1 ′) may be performed. Also, in the case where the automatic document feeder 6 is provided with an independent automatic discharge mode in which a document copied in the manual mode can be discharged from the platen glass 5 without opening the document cover 4. By applying the configurations shown in the first to third embodiments, the same effect can be obtained. Furthermore, when the automatic document feeder 6 stops the operation in the middle of automatically feeding the document in the automatic document feeding mode, the automatic document feeder 6 automatically discharges all the originals without leaving them on the platen glass 5, and then operates. 8 is configured to stop, if the control is changed depending on whether the JOB immediately before the stop is the manual mode or the automatic document feeding mode as shown in FIG. Control can be simplified by reducing the number of detections.

[0036]

As described above, according to the automatic document feeder according to the present invention, it is possible to automatically eject the remaining original document on the platen glass by the automatic document feeder. In some cases, this is automatically ejected, and only when the original cannot be ejected automatically, a warning is issued and the remaining original is manually removed. As a result, even if there is a residual document on the platen glass when the document is automatically fed by the automatic document feeder, if it can be automatically ejected, it will be automatically ejected by utilizing the automatic function. It is possible to make a copy without having to do so, and thus it becomes possible to improve the operability as compared with the prior art. In addition, if the remaining originals are thick paper, bound like a notebook or book, and if multiple originals are closed with clips or staples, it is determined that automatic ejection is impossible and automatic Since the document is not ejected, it is possible to prevent the document from being broken or damaged and being damaged.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of an image forming apparatus provided with an automatic document feeder according to the present invention.

FIG. 2 is a partial front sectional view showing a first form of the automatic document feeder.

FIG. 3 is a circuit configuration diagram of a document detection unit included in the automatic document feeder.

FIG. 4 is a flowchart showing a control method of the automatic document feeder.

FIG. 5 is a partial front sectional view showing a second form of the automatic document feeder.

FIG. 6 is a partial front sectional view showing a third form of the automatic document feeder.

FIG. 7 is a flowchart showing another example of a control method of the automatic document feeder.

FIG. 8 is a flowchart showing still another example of the control method.

[Explanation of symbols]

5 ... Platen glass, 6 ... Automatic document feeder, 8 ... Feed belt (feeding means, discharging means) 10, 20, 25 ... Detection sensor (document detecting means).

Claims (2)

[Claims] 1. An automatic document feeder provided in an image forming apparatus, comprising: a platen glass on which the document is placed for reading an image of the document; and a supply means for supplying the document onto the platen glass. An original detection unit that detects the thickness of the original on the platen glass, an ejection unit that ejects the original from the platen glass, and an original on the platen glass is based on the detection result of the original detection unit. Judgment means for judging whether or not the paper can be discharged by the discharge means, warning means for warning that the original is present on the platen glass, and the discharge means based on the judgment result by the judgment means, A control means for controlling the operation of the warning means, wherein the control means detects the thickness of the document on the platen glass by the document detection means. When the determination means determines that this is a thickness that can be discharged by the discharge means, the discharge means discharges the document from the platen glass, and the detected thickness of the document is not discharged by the discharge means. An automatic document feeder, characterized in that when the determination means determines that the thickness is possible, the warning means controls to warn that a document is present on the platen glass. 2. An automatic document feeder provided in an image forming apparatus, comprising a platen glass on which the document is placed for reading an image of the document, and a supply means for supplying the document onto the platen glass. A document detecting unit that detects a document on the platen glass, a discharging unit that discharges the document from the platen glass, and a document on the platen glass is discharged by the discharging unit based on a detection result of the document detecting unit. Judgment means for judging whether or not the document can be ejected, warning means for warning that the original is present on the platen glass, and based on the judgment result by the judgment means, the ejection means and the warning means A control means for controlling the operation, wherein the control means drives the discharging means for a predetermined time, and at this time, the platen is detected by the document detecting means. When the original document on the glass is detected and the original document moves by a predetermined size or more, the determination device determines that the original document can be ejected by the ejection device, and the ejection device ejects the original document on the platen glass. When the document is controlled to be discharged from above, and when the document is moved by a predetermined size or less, the determination unit determines that the document cannot be discharged by the discharge unit, and the warning unit The automatic document feeder is characterized in that it is controlled so as to warn that there is a document on the platen glass.