JPH10212057A - Sheet carrying device and image processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent poor carry due to deformation of a sheet from generating by allowing or prohibiting carry of the sheet based on the detected signals of the proper number of sheet detecting means arranged on the proper positions on a sheet tray. SOLUTION: A document loading part 4 is provided with a sheet tray 15 loading documents, and side guides 16, 17 regulating the end parts in the width direction of the loaded documents. A center sheet detecting sensor 18 is provided on the nearly center part in the sheet width direction of the sheet tray 15. A front part sheet detecting sensor 21 and a rear part sheet detecting sensor 22 are respectively provided on the sheet loading parts 16b, 17b of the side guides 16, 17. When all the sheet detecting sensors 18, 21, 22 detect the document, the document is carried, and when at least one of the sheet detecting sensors 18, 21, 22 does not detect the document, respective rollers are not driven, and operation is controlled so as not to carry the document. Hereby, carry of a deformed document is previously prohibited so as to prevent poor carry, breakdown, and the like from generating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeder used in an image processing apparatus, and more particularly, to a document feeder for feeding a document to, for example, an image reading section.

[0002]

2. Description of the Related Art Conventionally, in an image processing apparatus such as an electrophotographic copying machine, in order to read image information of an original, in addition to a method of reading an image of an original placed and fixed on a platen glass, the original is automatically read. There is known a method in which a document feeder conveys the image to image reading means and reads the image. The method of conveying a document using this automatic document feeder can process a large number of sheet documents in a short time, and has been widely used in recent years.

In this automatic document feeder, after the sheet document is placed on a sheet tray, the sheet document is conveyed to an image reading means by pressing a copy start switch, and is discharged after the image is read. It is discharged on a tray. In this case, in order to prevent an erroneous operation or the like, the automatic document feeder is generally made operable after detecting that a document has been placed on the sheet tray.

[0004]

However, in the above-described conventional apparatus, although a large number of sheet documents can be processed in a short time, there is a possibility that a document conveyance defect such as a paper feeding defect or a paper jam may occur. That is, a sheet document generally used as a document is often deformed, such as curled, unlike a sheet of transfer paper or the like on which no image is formed, and the deformation of the document is a main cause of document conveyance failure. Was. When this document conveyance failure occurs, not only the productivity of the document processing is reduced, but also the document may be damaged.

SUMMARY OF THE INVENTION An object of the present invention is to provide a highly productive sheet conveying apparatus which prevents a defective sheet feeding such as a manuscript or the like due to a deformation of the sheet and a conveying error such as a paper jam, and does not damage the sheet. Is to do.

[0006]

According to the present invention, there is provided a sheet tray on which a plurality of sheets can be stacked, a conveying means for separating and conveying the sheets one by one, First sheet detection means arranged at a substantially central portion in the width direction orthogonal to the sheet conveying direction on the sheet tray,
Second and third sheet detecting means arranged at substantially both ends in the width direction orthogonal to the sheet conveying direction on the sheet tray, and conveying the sheet by the conveying means based on a detection signal of each of the sheet detecting means. Control means for permitting or prohibiting.

[0007] According to the above arrangement, an appropriate number of sheet detecting means are arranged at appropriate positions on the sheet tray, and sheet conveyance by the conveying means is permitted or prohibited based on a detection signal of the sheet detecting means. Therefore, for example, when all of the sheet detection units detect a sheet, the conveyance of the sheet is permitted. When at least one of the sheet detection units does not detect the sheet, the conveyance of the sheet is permitted. By prohibiting the conveyance of the deformed document, it is possible to prohibit the conveyance of the deformed document beforehand, and it is possible to prevent the conveyance failure or breakage of the document.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a sheet conveying apparatus to which the present invention is applied will be specifically described below with reference to the drawings. In the following embodiments, a sheet conveying device used in an image processing apparatus will be described as an example.

[First Embodiment] An image processing apparatus according to a first embodiment will be described with reference to the drawings. In the following description, an image reading apparatus provided with an automatic document feeder as an image processing apparatus is illustrated. FIG. 1 is a schematic sectional view showing a schematic configuration of an image reading apparatus provided with an automatic document feeder to which the present invention is applied, and FIG. 2 is an explanatory diagram of a sheet tray in the automatic document feeder.

In FIG. 1, reference numeral 1 denotes an image reading device;
An automatic document feeder 2 feeds a document as a sheet to the image reading unit 3. The automatic document feeder 2 includes a document placing portion 4 on which a plurality of documents can be placed, a pickup roller 5 for feeding out the documents one by one, a separating portion 6 for separating multi-fed documents one by one, , 8, 9, 10 for transporting the read original to the original reading unit 3, a pair of transport rollers 12, for transporting the read original to the discharge tray 11.
13 and 14.

As shown in FIG. 2A, the document placing section 4 regulates and aligns a sheet tray 15 on which a document is placed with an end of the placed document in a width direction (a direction perpendicular to the conveying direction). It has side guides 16 and 17 as regulating means. At a substantially central portion of the sheet tray 15 in the sheet width direction, a central sheet detecting sensor 18 as a first sheet detecting unit is provided. As shown in FIGS. 2B and 2C, the central sheet detection sensor 18 is configured to detect the original by cutting off the photo interrupter 20 when the sensor flag 19 is pushed by the original. The side guides 16 and 17 are each
a, 17a and sheet stacking sections 16b, 17b, and are attached to the sheet tray 15 so as to be movable in the direction of arrow A according to the sheet width. Sheet loading section 16
A front sheet detection sensor 21 as a second sheet detection unit and a rear sheet detection sensor 22 as a third sheet detection unit are installed in b and 17b, respectively. The configuration of the front sheet detection sensor 21 and the rear sheet detection sensor 22 is the same as that of the center sheet detection sensor 18 (see FIGS. 2B and 2C), and therefore, detailed description is omitted here. Front seat detection sensor 21 and rear seat detection sensor 22 are side guides
Since the document is set at 16, 17, the document of any size is placed at the end in the sheet width direction.

As shown in FIG. 1, the image reading apparatus 1 comprises a first mirror stand 23, a second and third mirror stand 24, a lens 25, and a CCD sensor 26 as a reading element. The first mirror table 23 has an exposure lamp 2 for irradiating the image surface of the original.
7, a reflection shade 28, and a first mirror 29 for changing the angle of the reflected light (image light) of the irradiated document. The second and third mirror bases 24 further change the angle of the reflected light whose angle has been changed by the first mirror 29 and guide the reflected light to the CCD sensor 26 through the lens 25 and the third mirror 31.
Is provided.

Reference numeral 32 denotes a start key. Reference numeral 33 denotes a display unit as display means, which displays operation contents, input contents, warnings, and the like. Reference numeral 34 denotes an operation input unit for inputting a predetermined mode.

Reference numeral 40 denotes a CPU serving as control means, which controls the driving of the rollers and the components in the image reading apparatus 1 in accordance with signals from the sensors 18, 21 and 22 and various kinds of input information. ing.

Next, the operation of the image reading apparatus having the above-described automatic document feeder will be briefly described. First,
An original is placed on the sheet tray 15, and after inputting a predetermined mode with the operation input unit 34, the start key 32 is pressed. Then, the exposure lamp 27 is turned on, and the sheet feeding operation is started. That is, the pickup roller 5 rotates to feed out the original,
Unnecessary documents are separated by the separation unit 6, and one document is conveyed to the image reading unit 3 by the conveyance roller pairs 7, 8, 9, and 10.
The original is illuminated by an exposure lamp 27 while being conveyed. The reflected light is transmitted through mirrors 25, 30, and 31 to lens 25.
To form an image on the CCD sensor 26. Thereafter, the document is further transported downstream by the transport roller pairs 12, 13, and 14, and is discharged onto the discharge tray 11. This series of operations is repeated for the number of documents, and when the operation for the number of documents is completed, the exposure lamp 27 is turned off.

Next, the sheet tray 15 which is an essential part of the present invention is described.
Operation control according to the state of the original placed above will be described in detail with reference to FIGS. FIG. 3 is a diagram illustrating the state of the sheet detection sensor on the sheet tray, and FIG. 4 is a diagram illustrating operation control according to detection information of the sheet detection sensor.

In this embodiment, the sheet detection sensor 1
When all of the documents 8, 21, and 22 detect the document, the rollers are driven to convey the document, and the sheet detection sensor is used.
When at least one of the sheet detection sensors 18, 21, and 22 does not detect a document, the operation is controlled so that the rollers are not driven and the document is not conveyed. That is, the sheet detection sensors 18, 21, and 22 determine that there is no original when all of them are off, and determine that there is an original and that the original can be transported when all of them are on. It is configured to determine that it is impossible.

FIG. 3A is a view showing a case where no original is placed on the sheet tray 15. In this case, since the sheet detection sensors 18, 21, and 22 are not pressed,
The document is in the ff state, it is determined that there is no document, and document conveyance and image reading operations are prohibited.

FIG. 3B is a view showing a case where a transportable original G is placed on the sheet tray 15. In this case, the sheet detection sensors 18, 21, and 22 are all turned on. Accordingly, a display indicating that the document conveyance and the image reading operation are possible is displayed on the display unit 33, and the apparatus is in a state where the document conveyance and the image reading operation are possible and stands by. Thereafter, when the start key 32 is pressed, the document conveyance and the image reading operation are started as described above.

FIG. 3C is a diagram showing a case where a document G curled largely upward is placed on the sheet tray 15. In this case, the center sheet detection sensor 18 is pushed and turned on, but the front and rear sheet detection sensors 21 and 22 are not turned on. Therefore, it is determined that the original is placed but not suitable for conveyance,
A display to the effect that the operator is prompted to “correct the upper curl and redo the operation again” is displayed on the display unit 33. At this time, the document conveyance and the image reading operation are prohibited. The operator looks at the display and corrects the deformation of the manuscript,
Perform the same operation again. At this time, if the deformation of the document is sufficiently corrected, the state shown in FIG. 3B is reached, and the document conveyance and the image reading operation are permitted.

FIG. 3D is a view showing a case where a document G curled greatly downward is placed on the sheet tray 15. In this case, the front and rear sheet detection sensors 21 and 22 are pushed and turned on, but the center sheet detection sensor 18 is not turned on. Therefore, it is determined that the original is placed but not suitable for conveyance,
A display to the effect that prompts the operator to “correct the lower curl and perform the operation again” is displayed on the display unit 33. At this time, the document conveyance and the image reading operation are prohibited. The operator looks at the display and corrects the deformation of the manuscript,
Perform the same operation again. At this time, if the deformation of the document is sufficiently corrected, the state shown in FIG. 3B is reached, and the document conveyance and the image reading operation are permitted.

As described above, by arranging an appropriate number of sheet detection sensors at appropriate positions on the sheet tray, and permitting or prohibiting the conveyance of the sheets based on the detection signals of the sheet detection sensors, the details are described above. When all of the sheet detection sensors detect the sheet, the conveyance of the sheet is permitted,
When at least one of the sheet detection sensors does not detect a sheet, the conveyance of the deformed document can be prohibited beforehand by prohibiting the conveyance of the sheet. Can be prevented.

[Second Embodiment] In the above-described embodiment,
Although the configuration in which the original directly presses the sheet detection sensor has been described, the present invention is not limited to this, and may have a configuration as shown in FIGS. 5 and 6, for example. Hereinafter, the present embodiment will be described. However, the same parts as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted. In the present embodiment, a sensor that performs purely optical detection of a document is used as the sheet detection unit.

In FIGS. 5 and 6, reference numeral 35 denotes a central sheet detecting sensor as first sheet detecting means, which is constituted by a light emitting sensor 35a and a light receiving sensor 35b. The sensor 35 receives light from the light emitting sensor 35a and receives light from the light receiving sensor 35b.
, It is determined that a document exists.

In the sensor 35, as shown in FIG. 6, a light emitting sensor 35a and a light receiving sensor 35b are arranged at an angle of about 90 degrees. Therefore, as shown in FIG. 6A, the light emitted from the light emitting sensor 35a does not reach the light receiving sensor 35b when there is no original. Also, as shown in FIG.
When the document G is placed almost in close contact with the upper surface 15a of the sheet tray 15, the light emitted from the light emitting sensor 35a is reflected on the document surface and reaches the light receiving sensor 35b to determine that the document is present. As shown in FIG. 6D, the original G is placed on the sheet tray 15.
When the light is emitted above the upper surface 15a by a predetermined amount or more, the light emitted from the light emitting sensor 35a is reflected on the original surface but does not reach the light receiving sensor 35b.

In FIGS. 5 and 6, reference numeral 36 denotes a front sheet detection sensor as second sheet detection means, which comprises a light emitting sensor 36a and a light receiving sensor 36b. As shown in FIG. 6, the sensor 36 has a side guide so that the light emitting portion of the light emitting sensor 36a faces the light receiving portion of the light receiving sensor 36b.
The light receiving sensor 36b is arranged to determine that there is no original when the light from the light emitting sensor 36a is received by the light receiving sensor 36b. Then, when the light from the light emitting sensor 36a does not reach the light receiving sensor 36b, that is, when the document has traversed the optical path, it is determined that there is a document (FIG. 6B,
(D)).

In FIGS. 5 and 6, reference numeral 37 denotes a rear sheet detecting sensor as third sheet detecting means. The rear seat detection sensor 37 is disposed on the side guide 17, and the other configuration is the same as the configuration of the front seat detection sensor 36, and thus the detailed description is omitted here.

Even with the above-described configuration, the same sheet detection as in the above-described embodiment can be performed, and by permitting or prohibiting sheet conveyance based on the detection information (see FIG. 4), the above-described embodiment can be performed. The same effect as in the embodiment can be obtained.

[Other Embodiments] In the above-described embodiment,
Although the configuration in which the sheet detecting means for detecting the sheet is disposed at the center and both ends in the sheet width direction has been exemplified, the number and the location of the sheet detecting means are not limited to this, and the sheet What is necessary is just to arrange an appropriate number of sheet detecting means at an appropriate position on the tray.

In the above-described embodiment, an image reading apparatus for reading an image of a document is described as an example of the image processing apparatus. However, the image processing apparatus is not limited to this. For example, a printer for recording and forming an image on a sheet such as transfer paper, facsimile,
It is also effective to apply the present invention to another image processing apparatus such as a copying machine.

[0031]

As described above, according to the present invention,
Since an appropriate number of sheet detection units are arranged at appropriate positions on a sheet tray, and the sheet conveyance by the conveyance unit is permitted or prohibited based on a detection signal of the sheet detection unit, for example, the sheet detection is performed. When all of the units detect a sheet, the conveyance of the sheet is permitted, and when at least one of the sheet detection units does not detect the sheet, the conveyance of the sheet is prohibited. It is possible to prohibit the conveyance beforehand, and it is possible to prevent the conveyance failure or breakage of the document.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a schematic configuration of an image reading apparatus provided with an automatic document feeder to which the present invention is applied.

FIG. 2 is an explanatory diagram of a sheet tray in the automatic document feeder.

FIG. 3 is a sectional view showing an example of a state of a sheet detection sensor on the sheet tray.

FIG. 4 is a diagram showing an example of operation control according to detection information of the sheet detection sensor.

FIG. 5 is an explanatory diagram of a sheet tray according to another embodiment.

FIG. 6 is a sectional view showing an example of a state of a sheet detection sensor on a sheet tray according to another embodiment.

[Explanation of symbols]

 G: Document 1: Image reading device 2: Automatic document feeder 3: Image reading unit 4: Document placement unit 5: Pickup roller 6: Separation unit 7, 8, 9, 10, 12, 13, 14: Transport roller pair 11: Discharge tray 15: Sheet tray 15a: Upper surface 16, 17: Side guide 16a, 17a: Width restricting portion 16b, 17b: Sheet placing portion 18, 35: Central sheet detection sensor 19: Sensor flag 20, 36: Photo interrupter 21, 37 ... Front sheet detection sensor 22 ... Rear sheet detection sensor 23 ... First mirror stand 24 ... Second and three mirror stand 25 ... Lens 26 ... CCD sensor 27 ... Exposure lamp 28 ... Reflector shade 29 ... First mirror 30 ... Second mirror 31 ... Third mirror 32 ... Start key 33 ... Display part 34 ... Operation input part 35a, 36a, 37a ... Light emission sensor 35b, 36b, 37b ... Light emission sensor 40 ... CPU

Claims (6)

[Claims] 1. A sheet tray on which a plurality of sheets can be stacked, a conveying unit for separating and conveying the sheets one by one, and a sheet tray disposed at a substantially central portion in a width direction orthogonal to a sheet conveying direction on the sheet tray. First sheet detecting means, and second and third sheet detecting means disposed at substantially both ends in the width direction orthogonal to the sheet conveying direction on the sheet tray, based on a detection signal of each of the sheet detecting means. Control means for permitting or prohibiting the conveyance of the sheet by the conveyance means. 2. When all of the sheet detecting means detect a sheet, the conveyance of the sheet is permitted. When at least one of the sheet detecting means does not detect the sheet, the conveyance of the sheet is permitted. The sheet conveyance device according to claim 1, wherein the sheet conveyance is prohibited. 3. A sheet dispenser which is disposed on the sheet tray, is movable in a width direction orthogonal to a sheet conveying direction, and regulates both ends of the sheet in the width direction. The sheet conveying device according to claim 1, further comprising a third sheet detecting unit. 4. A display means for displaying information based on a state of a sheet detected by each of the sheet detecting means, and contents permitting conveyance of the sheet when all of the sheet detecting means detect a sheet. The display means displays on the display means, and when at least one of the sheet detection means does not detect a sheet, a content prohibiting the conveyance of the sheet is displayed on the display means. The sheet conveying device according to claim 1. 5. An image processing apparatus for performing predetermined image processing on a sheet, the sheet conveying apparatus according to claim 1, wherein the sheet conveying apparatus conveys the sheet to an image processing unit. An image processing apparatus comprising: 6. The image processing apparatus according to claim 5, wherein the image processing apparatus is an image reading apparatus that reads an image on a sheet or an image forming apparatus that records and forms an image on a sheet.