JP2004238162A - Sheet conveyance device, image reading device, and image formation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet conveyance device capable of conveying a sheet body satisfactorily while preventing the sheet body from becoming dirty and to provide an image reading device and an image formation device. <P>SOLUTION: A call-in roller R1 and a separation roller R2 take in a document set on a document tray 22 from the uppermost layer. When a tip of the taken-in document is detected by a paper feeding detector S3 and a predetermined period of time elapses, a tip part of the taken-in document is nipped and held between a pair of rotating conveyance rollers R3 and R4, and the document tray 22 is lowered by a predetermined amount in this condition. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is provided in an image reading apparatus such as a scanner, or an image forming apparatus such as a copier, and sequentially takes out and transports a plurality of originals or sheet bodies such as recording paper stored in a stacked state in a sheet storage unit. The present invention relates to a sheet conveying device, an image reading device including the sheet conveying device, an image forming device including the sheet conveying device, and an image forming device including the image reading device.
[0002]
[Prior art]
2. Description of the Related Art In recent years, an image forming apparatus or the like has been equipped with an image reading apparatus that automatically takes a sheet-shaped document one by one and sequentially reads and conveys the image to perform image reading and image formation. Have been. On the other hand, advances in digital technology have increased the speed of reading original images, converting the data obtained by reading to electronic data, and forming images based on the electronic data, so that a larger number of originals can be processed at high speed. It is becoming possible. Along with this, the number of documents that can be set at one time in the image reading apparatus has become extremely large, about 100 to 200 sheets.
[0003]
However, when the number of set originals increases, in the configuration in which the original tray on which the originals are placed is fixed, the conditions for taking out the originals from the original tray by the sheet conveying means (contact roller for taking out the originals) Position and contact pressure). For this reason, there is known an apparatus in which a document tray can be moved up and down by an elevating means controlled by a control means, and an upper surface of a set of originals to be placed is maintained at a predetermined height position (for example, see Patent Document 1). 1 and Patent Document 2.).
[0004]
[Patent Document 1]
JP-A-9-30658
[Patent Document 2]
JP-A-59-92938
[0005]
[Problems to be solved by the invention]
However, in the above-described apparatus capable of setting a large number of originals, it is possible to keep the original taking-out conditions constant, but the loading roller always comes into contact with the original bundle at a predetermined pressure due to its own weight or the like. ing. Therefore, the original being fed is rubbed while being pressed against the next original to be fed by the pressing force of the feeding roller, and adheres to the lower surface (reverse side) of the original being fed. There is a problem that the contaminants adhere to the upper surface (front surface) of the next document to be fed, and as a result, the quality of image reading and image formation deteriorates. The dirt adhering to the document is, for example, a toner having an insufficiently fixed image already formed on the back surface, or a pencil used for writing.
[0006]
The present invention has been made in view of such circumstances, and an object of the present invention is to use an intake roller at a timing at which the conveying means starts conveying the sheet taken out from the sheet storage means by the extracting means. Since the pressing of the sheet body is released, a sheet conveying apparatus capable of favorably conveying the sheet body while suppressing contamination of the sheet body, an image reading apparatus including the sheet conveying apparatus, An object of the present invention is to provide an image forming apparatus including a sheet conveying device and an image forming apparatus including the image reading device.
[0007]
[Means for Solving the Problems]
The sheet conveying device according to the present invention includes a sheet storage unit that stores a plurality of sheets in a sheet storage unit, a lifting unit that moves the sheet storage unit up and down, and a predetermined height position as a sheet extraction position. Take-out means for taking out the sheet body from the uppermost layer in contact with the upper surface of the sheet body contained in the sheet containing means, and carrying means for carrying the sheet body taken out by the take-out means to a predetermined position, Control means for controlling the elevating means so that the upper surface of the sheet body accommodated in the sheet accommodating means coincides with the sheet take-out position to elevate the sheet accommodating means. Thus, in synchronization with the timing at which the conveyance unit starts conveying the sheet body, the contact of the take-out unit with the sheet body is released. And wherein the are.
[0008]
In the present invention, when the sheet taken out from the sheet storage means which has been raised so as to coincide with the sheet take-out position starts to be conveyed by the conveying means, the contact of the sheet by the take-out means is released. At the contact surface between the sheet being fed and the sheet to be fed next after being stored in the sheet storage means, the dirt adhering to one of the sheet bodies due to the pressing force of the take-out means such as an intake roller. Adhere to the other sheet member can be minimized. Further, the release of the contact with the sheet body by the take-out means is performed in synchronization with the timing at which the conveyance means starts to convey the sheet body taken out by the take-out means. Is performed.
[0009]
Further, in the sheet conveying apparatus according to the present invention, the control means controls the elevating means so that the sheet accommodating means descends in synchronization with a timing at which the conveying means starts conveying the sheet body. It is characterized by having.
[0010]
In the present invention, when the sheet body taken out of the sheet storage unit that has been raised to match the sheet take-out position starts to be conveyed by the conveyance unit, the sheet storage unit is lowered, so that the sheet body being fed is The dirt attached to one sheet body is transferred to the other sheet body by a pressing force of a take-out means such as a pull-in roller at a contact surface with a sheet body which is stored in the sheet storage means and fed next. Adhesion can be minimized. Further, since the lowering of the sheet storage means is performed in synchronization with the timing at which the conveying means starts conveying the sheet taken out by the take-out means, the sheet means is reliably conveyed by the conveying means.
[0011]
The determination of the timing of starting the conveyance of the sheet by the conveyance unit is performed based on the elapsed time from the drive start timing of the unloading unit, the output of a sensor provided near the conveyance unit that detects the passage of the sheet, and the like. be able to. Further, after lowering the sheet accommodating means, the timing of raising the sheet accommodating means to take out the next sheet is determined based on sheet size information detected or set in advance and the driving start timing of the ejecting means. This can be performed based on the elapsed time, or based on the output of a sensor that detects the passage of a sheet member provided in the vicinity of the conveyance unit, or the like.
[0012]
Further, in the sheet transporting device according to the present invention, the amount by which the sheet accommodating unit descends is an amount by which the upper surface of the sheet body accommodated in the sheet accommodating unit is separated from the take-out unit. .
[0013]
In the present invention, the amount by which the sheet housing means descends is the amount by which the sheet body housed in the sheet housing means is separated from the take-out means such as a pull-in roller. The pressure can be reduced to the minimum necessary amount. In this way, at the contact surface between the sheet being fed and the sheet to be fed next, not only the dirt already attached to one sheet is suppressed from adhering to the other sheet, Since the sheet storage means in the lowered state can be raised and the transition time until the next sheet body can be taken out can be shortened as much as possible, the supply loss can be minimized.
[0014]
Further, the image reading apparatus according to the present invention is an image reading apparatus that takes in a sheet document and reads the image of the document by the image reading means, and conveys the sheet document to the image reading position of the image reading means. And a sheet conveying device according to any one of the above.
[0015]
In the present invention, the document being fed is pressed against the document being fed by the pressing force of the take-out means such as a retrieving roller at the contact surface between the document being fed and the next document stored in the sheet storage means and fed. Dirt that has already adhered to the next document to be fed can be minimized. As a result, it is possible to prevent the quality of reading the image of the document from being deteriorated.
[0016]
In the image forming apparatus according to the present invention, in an image forming apparatus for forming an image on a sheet-shaped recording medium by an image forming unit, the sheet-shaped recording medium is conveyed to an image forming position by the image forming unit. And a sheet conveying apparatus according to any one of the above-described inventions.
[0017]
In the present invention, at the contact surface between the recording paper being fed and the recording paper that is stored in the sheet storage means and fed next, one of the recording papers is pressed by the pressing force of the take-out means such as an intake roller. It is possible to minimize the contamination that has already adhered to the other recording paper. As a result, it is possible to prevent a decrease in image formation quality. This is particularly effective when a recording paper on which an image is formed or written on one surface, that is, a so-called backing paper, is used as the recording paper.
[0018]
Furthermore, an image forming apparatus according to the present invention is an image forming apparatus that reads an image on a sheet document to form an image, and includes the image reading device according to the above-described invention for reading an image on a sheet document. I do.
[0019]
In the present invention, the document being fed is pressed against the document being fed by the pressing force of the take-out means such as a retrieving roller at the contact surface between the document being fed and the next document stored in the sheet storage means and fed. An image reading apparatus is provided that can minimize the amount of dirt that has already adhered to the next document to be fed, thereby preventing deterioration in image reading quality of the document. As a result, it is possible to prevent the quality of the formed image from deteriorating.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described with reference to the drawings showing the embodiments.
Embodiment 1
FIG. 1 is a vertical cross-sectional view showing an overall mechanical configuration of a scanner 1 as an image reading apparatus provided with a sheet conveying device according to the present invention.
The scanner 1 mainly includes an optical system 2 and an ADF (Automatic Document Feeder) 3 disposed above the optical system 2, and can read both sides of a document for a copying machine, a facsimile machine, and the like. Used as a simple scanner.
[0021]
The optical system 2 is a first reading unit that is installed at a fixed position by a light source unit 13 and a mirror unit 14 to read an image of a document placed on a document table (platen glass) 12 and supported on a top surface. The image is read by forming an image on a CCD image sensor 11b via an imaging lens 11a of a CCD (Charge Coupled Device) reading unit 11.
[0022]
The light source unit 13 passes only a light source 13a, a concave reflector 13b for condensing reading illumination light emitted from the light source 13a at a predetermined reading position on the document table 12, and reflected light from the document. It is composed of a slit 13c, a mirror 13d and the like arranged such that the reflection surface is 45 degrees with respect to the surface of the document table 12 in order to change the optical path of the light passing through the slit 13c by 90 degrees. The mirror unit 14 includes a pair of mirrors 14a and 14b arranged such that the reflection surfaces are orthogonal to each other to further change the optical path of the light whose optical path has been changed by 90 degrees by the mirror 13d of the light source unit 13 by 180 degrees. It has.
The CCD reading unit 11 includes an imaging lens 11a that forms an image of the light from the mirror unit 14, and a CCD image sensor 11b that outputs an electric signal corresponding to the light formed by the imaging lens 11a.
[0023]
The light source unit 13 moves in the direction of the arrow 15 (sub-scanning direction) in parallel with the surface of the document table 12, as indicated by reference numerals 13e, 13f, and the like. By moving in the direction of arrow 15 (sub-scanning direction) in parallel, the image of the document placed on the document table 12 can be read. In this case, assuming that the moving speed of the light source unit 13 is V, the moving speed of the mirror unit 14 needs to be V / 2. The movement of the light source unit 13 and the mirror unit 14 is performed by a stepping motor 42 (shown in FIG. 2).
[0024]
The CCD reading unit 11 scans at a speed V a unit of a reduced reading optical system or a unit magnification reading optical system in which at least a CCD image sensor 11b, an imaging lens 11a, and a light source 13a are configured as one unit, and the light source 13a Alternatively, a configuration may be adopted in which reflected light from a document irradiated from the original is imaged on the CCD image sensor 11b via the imaging lens 11a.
[0025]
The optical system 2 is provided with a document table 16 at a position separated from the document table 12 in the sub-scanning direction. The light source unit 13 can read an image on one surface (hereinafter, this surface is referred to as a front surface) of the document conveyed on the document table 16 in a state of being stationary below the document table 16. A paper output tray 17 is provided near the exit of the document conveyed on the document table 16.
[0026]
On the other hand, the ADF 3 has a CIS (Contact Image Sensor) 21 as a second reading unit at a position facing the document table 16. The ADF 3 takes in the sheet-like originals placed on the original tray 22 in a stacked state one by one, and causes the CIS 21 to read an image on the other surface of the original (hereinafter, this surface is referred to as a back surface). For this reason, the ADF 3 further includes various rollers R1 to R11, detectors S1 to S6, a curved conveyance path 23, and a registration / skew correction area 24. The CIS 21 includes, for example, an array of image sensors, an array of light guides (a lens array such as a SELFOC lens), a light source (an LED array light source or a fluorescent lamp), and the like.
[0027]
The various rollers R1 to R11 are driven by a document conveying motor 43 (shown in FIG. 2). As will be described later in detail, a clutch 44 (shown in FIG. 2) is attached to the separation roller R2 connected to the attraction roller R1 by a transmission means such as a belt, and a clutch is attached to one of the registration rollers R8 and R9. 45 (shown in FIG. 2) are connected to each other, and the clutches 44 and 45 are disconnected under the control of a control unit 41 (shown in FIG. 2), which will be described later. The power is transmitted or blocked by the roller R1, the separation roller R2, and the registration rollers R8 and R9.
[0028]
The document tray 22 is electrically driven, and when it detects that a document has been set by an optical document detector S1 including an actuator S1a and a sensor body S1b, the document tray 22 starts to rise at a predetermined timing, and the placed document is started. The uppermost document of the bundle pushes up the intake roller R1. The pull-in roller R1 is supported by an arm 25 so as to be vertically movable. When the attraction roller position detector S2 detects that the attraction roller R1 has been displaced, specifically, has been pushed up, the document tray 22 temporarily stops rising, and enters a standby state.
[0029]
Note that if the document tray 22 is left for a predetermined period of time without inputting a signal to start reading after the document is set and the document rises as described above and enters the standby state, the document tray 22 remains in the standby state. May be continued, but it is desirable to prevent the deformation of the attraction roller R1 by temporarily descending to a predetermined height position to enter a standby state.
[0030]
When a document feed start signal is input, the intake roller R1 and the separation roller R2 are driven to rotate, and the uppermost document of the document bundle is sequentially captured. The attraction roller R1 is supported by an arm 25, and the arm 25 is rotatably supported by the rotation shaft of the separation roller R2. Then, the attraction roller R1 comes into contact with the uppermost document set on the document tray 22 by its own weight. The pull-in roller R1 is prevented from descending more than necessary by a stopper 52 (shown in FIG. 3). As will be described later, a convex portion 25a (shown in FIG. 3) is formed on the side surface of the arm 25, and a call-in device configured by an optical sensor or the like including a light emitting element S2a and a light receiving element S2b (shown in FIG. 3). The roller position detector S2 can detect the current height position of the attraction roller R1 based on the rotation angle of the arm.
[0031]
In the present embodiment, a protrusion 25a is provided on the arm 25, and a pull-in roller position detector S2 is installed. The height position of the pull-in roller R1 is directly determined by the pull-in roller position detector S2. Although it is configured to detect, the pull-in roller position detector S2 may be provided at a position distant from the arm 25. In this case, if the height of the arm 25 can be detected using the movable connecting means, Good.
[0032]
A roller R2a having a torque limiter (a friction pad may be used instead) is provided to face the separation roller R2. Therefore, even when a plurality of originals are taken in by the call-in roller R1, only the uppermost document that is in close contact with the call-in roller R1 is taken in by the separation rollers R2 and R2a, and the originals are not double fed. One document is reliably separated. Whether or not the document is reliably separated and supplied by the separation rollers R2 and R2a is detected by a sheet feed detector S3 including an actuator S3a and a sensor main body S3b. Then, the document is transported to the downstream curved transport path 23 at a predetermined timing.
[0033]
In the curved conveyance path 23, the document is conveyed by conveyance rollers R3 to R7, and whether or not the document is conveyed without difficulty includes an actuator S4a and a sensor main body S4b. It is detected by the paper detector S4. The curved transport path 23 is configured to have a curvature that allows a manufacturer to guarantee that all types of originals can be transported stably. Specifically, the curved conveyance path 23 is formed to have a curvature that allows smooth conveyance of the thickest, that is, the stiffest document among the readable documents.
[0034]
The document discharged from the curved conveyance path 23 is conveyed to the registration / skew correction area 24. When the leading edge of the document is detected by the paper feed detector S5 disposed in front of the registration rollers R8 and R9 installed near the exit of the registration / skew correction area 24, the registration rollers R8 and R9 are stopped. Then, the leading edge of the document is caused to collide with the registration rollers R8 and R9 at the joint between the registration rollers R8 and R9 for a predetermined time due to the conveyance force from the upstream side. Thus, registration and skew of the document are corrected. The sheet feed detector S5 includes an actuator S5a and a sensor body S5b.
[0035]
The registration / skew correction area 24 is a section from the conveyance roller pair R6, R7 installed near the exit of the curved conveyance path 23 to the registration roller pair R8, R9. In the registration / skew correction area 24, the state of the document S becomes substantially linear between the roller pairs R6 and R7 and the roller pairs R8 and R9 so that the above-described registration and skew correction of the document can be performed. It is designed to be as free as possible from the guide surface of the transport path. Note that the distance between the roller pair R6, R7 and the roller pair R8, R9 is such that the minimum length of the document that can be processed as a document feeder in the transport direction is secured. Just fine. That is, the shorter the trailing edge of the document remaining in the curved conveyance path 23, the smoother the registration and skew correction of the document can be performed.
[0036]
The document whose registration and skew correction has been performed in the registration / skew correction area 24 resumes conveyance at a predetermined timing, is conveyed to a first reading position Pos1 for exposing and scanning the front surface of the document, and then continues the document. Pass through a second reading position Pos2 for exposing and scanning the back surface of the image. The light source unit 13 faces the first reading position Pos1, and the CIS 21 faces the second reading position Pos2.
[0037]
In this manner, the originals on which the images on the front surface or the front and back surfaces are read are discharged from the original discharge position on the side surface of the scanner 1 by discharge rollers R10 and R11 (the discharge roller R11 is provided on the optical system 2 side). Is discharged onto the discharge tray 17 supported at a lower position. Confirmation of the operation of discharging the document onto the discharge tray 17 is detected by a discharge detector S6 including an actuator S6a and a sensor body S6b.
[0038]
The above-described operation is repeated until there are no more documents set on the document tray 22, and all the documents that have been read are sequentially discharged onto the discharge tray 17.
[0039]
By the way, since the height of the document bundle gradually decreases as the documents on the document tray 22 are sequentially fed, the document tray 22 is raised by that amount, so that when the document is taken out, the maximum of the document bundle is always obtained. The upper surface and the intake roller R1 are controlled so that a predetermined height relationship can be maintained. That is, the document tray 22 is raised so that the top surface of the document bundle coincides with a predetermined height position (document removal position) at which the loading roller R1 takes out the document. For this purpose, the document tray 22 is swingable about the fulcrum 22a, but the rib 22b provided at the end opposite to the fulcrum 22a is pushed up by the elevating plate 31 so that the document tray 22 is raised. The document tray 22 is lowered so that the document tray 22 can be lifted and vice versa. The lift plate 31 has an end opposite to the rib 22b fixed to a lift plate support shaft 32. The lift plate support shaft 32 is connected to a lift motor 34 via a lift mechanism 34 composed of a row of transmission members (gears). It is rotationally driven by 33.
[0040]
The position of the document tray 22 at the time of standby is controlled by a control unit 41 (shown in FIG. 2), which will be described later, driving and driving the elevating motor 33 of the elevating mechanism unit 34 based on a detection signal of the attraction roller position detector S2. Maintained by The standby position of the document tray 22 can be arbitrarily set by operating the operation unit 46 (shown in FIG. 2) described later according to the number of documents frequently set on the document tray 22. , Can be set in advance by a service person or a user.
[0041]
Further, the document tray 22 has a height position on the entrance side and a height position on the exit side of the curved conveyance path 23 which are inevitably formed by the curved conveyance path 23 set so as to guarantee the stable conveyance of the document as described above. It can be moved up and down within the range between the height position. When the document tray 22 moves downward in this range, the distance between the document feeder roller R1 and the document feed roller R1 becomes large, so that a large amount of documents can be placed. By raising one of the uppermost layers of the bundle of originals to a position where the uppermost layer of the bundle of originals can be fed to the entrance of the curved conveyance path 23, the uppermost layer of the large number of original bundles placed on the original tray 22 is sequentially fed. You can do it.
[0042]
In addition, the document tray 22 is provided with a document regulating plate 30 for regulating and aligning the side portions of the document bundle. The document tray 22 further includes a first document size detector S0 for detecting the width of the document (length in a direction orthogonal to the document feeding direction), and a document length (document feeding direction). ) Is provided with a second document size detector S7 including an actuator S7a for detecting the length of the original document and a sensor main body S7b. The size of the document placed on the document tray 22 is detected by the first document size detector S0 and the second document size detector S7, and paper selection or the like at the time of image formation is performed based on the detection result. .
[0043]
On the other hand, when reading a document on the document table 12, the light source unit 13 moves from Pos3 (start position of the light source unit 13 when reading a still document, hereinafter referred to as a third position) to position Pos4 (maximum) in FIG. A third document size detector S9 (FIG. 8) for detecting the size of the document placed on the document table 12 in the direction of the return position of the light source unit 13 when reading the document, hereinafter referred to as a fourth position. 2) is moved by a predetermined distance in accordance with the size of the original document detected in the above-described manner.
[0044]
On the other hand, when reading the original while transporting it, the light source unit 13 is stopped at the first reading position Pos1 (the position of the light source unit 13 when reading the traveling original). In addition, the light source unit 13 detects any one of the third position Pos3, the fourth position Pos4, or an intermediate position between the third position Pos3 and the first reading position Pos1 with the position detector of the light source unit 13. The home position is set based on the detection result of the light source unit detector S8 (shown in FIG. 2). Therefore, the light source unit 13 is stopped at this home position during standby when not in use.
[0045]
The ADF 3 uses a hinge (not shown) provided between the optical system 2 and a part on the back side (the back side of the paper) of the scanner 1 to read a document placed on the document table 12. It is rotatably supported. The ADF 3 rotates upward with respect to the document table 12 and opens using the hinge as a pivot point. As a result, the upper surface of the document table 12 can be opened from the near side, and a non-sheet document that cannot be conveyed by the ADF 3, such as a book document, can be set on the document table 12. A document mat 35 made of a material having elasticity is provided on the surface of the bottom surface of the ADF 3 which is in contact with the document table 12 so as to face the document table 12.
[0046]
The scanner 1 configured as described above can read an original in three types of modes: a stationary reading mode, a traveling reading mode, and a double-sided reading mode. The stationary reading mode is a mode for reading a document such as a book, and scans the document placed on the document table 12 with the light source unit 13 and the mirror unit 14 in a direction indicated by an arrow 15 while scanning the CCD reading unit. 11 is a reading mode. In both the traveling reading mode and the duplex reading mode, the ADF 3 reads the originals set on the original tray 22 while automatically feeding the originals one by one. The original is read using the CCD reading unit 11 in the traveling reading mode, and is read using both the CCD reading unit 11 and the CIS 21 in the double-side reading mode.
[0047]
In the present embodiment, the maximum number of documents that can be set on the document tray 22 is, for example, about 200 if the thickness is about the same as ordinary copy paper.
[0048]
FIG. 2 is a block diagram showing a functional configuration of the scanner 1 according to the present invention whose mechanical configuration is shown in FIG. In FIG. 2, the same or corresponding parts as those in the configuration shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.
[0049]
A control unit 41 realized by a microcomputer or the like includes a first document size detector S0, a second document size detector S7 for detecting the size of a document set on the document tray 22, and a document placed on the document table 12. The detection result of the third document size detector S9 for detecting the size of the original document is given. The control unit 41 switches the control of the paper to be used and the timing based on the detection results of the document size detectors S0, S7, and S9.
[0050]
At the time of reading using the CCD reading unit 11, the control unit 41 controls the driving of the stepping motor 42 to move the light source unit 13 and the mirror unit 14 as described above, and the light source detected by the light source unit detector S8. The original image is read by controlling the exposure lamp 13a and the CCD image sensor 11b according to the position of the unit 13.
[0051]
On the other hand, at the time of reading using the ADF 3, the control unit 41 controls the drive of the elevating motor 33 based on the detection result of the attraction roller position detector S2 to set the document on the document tray 22. While maintaining the height of the uppermost surface of the bundle of originals at a constant height (a predetermined original take-out position), each of the detectors S3 to S6 until the original detector S1 detects that the originals on the original tray 22 are exhausted. The CCD image sensor 11b and / or the CIS 21 are controlled while the document is conveyed by controlling the document conveying motor 43, the clutch 44 of the pull-in roller R1, and the clutch 45 of the registration roller pair R8, R9 based on the detection result. Scan the original image.
[0052]
The control unit 41 further displays necessary information on an operation unit 46 including a liquid crystal touch panel or the like, and receives an input operation applied to the operation unit 46.
[0053]
FIG. 3 is a schematic side view illustrating a mechanical configuration around the document tray 22 for explaining the elevating operation of the document tray 22.
[0054]
FIG. 3A is a schematic diagram illustrating a state where a document set on the document tray 22 is being taken. The height of the uppermost surface of the bundle of originals 51 set on the original tray 22 reaches a predetermined original take-out position by raising the original tray 22 until the attraction roller position detector S2 outputs ON as a detection result. ing. By rotating the take-in roller R1 and the separation roller R2, one document 51a on the uppermost layer of the document bundle 51 is taken in.
[0055]
When a predetermined time elapses after the sheet feed detector S3 detects the leading end of the taken-in document 51a, as shown in FIG. 3B, the leading end of the document 51a is moved to the rotating transport roller pair R3, R4. In this state, the document tray 22 is lowered by a predetermined amount, as indicated by an arrow 56. That is, the document tray 22 is lowered at the timing when the pair of conveyance rollers R3 and R4 start conveying the document 51a. Accordingly, the loading roller R1 also descends, but since the stopper 52 prevents the descending from a predetermined height position, the pressing of the scanning roller bundle R1 against the document bundle 51 is released.
[0056]
As a result, the dirt 53 adhering to the lower surface (back surface) of the document 51a being fed is removed from the upper surface (front surface) of the uppermost document (document to be fed next) 51b of the document bundle 51. ) Can be suppressed.
The predetermined time is a theoretical time required from the time when the leading edge of the document 51a passes through the paper feed detector S3 to the time when the leading edge reaches the pair of transport rollers R3 and R4.
Further, the timing of lowering the document tray 22 may be determined based on the time elapsed since the start of rotation of the attraction roller R1 by the clutch 44.
[0057]
When the original 51a is further conveyed and the paper feed detector S3 detects the trailing end of the original 51a, it is determined that the trailing end of the original 51a has already passed through the call-in roller R1 and the separation roller R2, as shown in FIG. In order to prepare for taking out the next original 51b, as shown by an arrow 57, the original tray 22 is raised until the detection result of the attracting roller position detector S2 is turned on, so that the uppermost surface of the original bundle 51 is Is the predetermined document take-out position. Thereafter, the original 51b is fed in the same manner as the original 51a. Then, the same operation is repeated for the remaining originals.
The timing of raising the document tray 22 may be determined based on the time elapsed since the start of rotation of the attraction roller R1 by the clutch 44 and the size of the document detected in advance.
[0058]
By the above-described lifting operation, as shown in FIG. 3D, in the conventional configuration in which the call-in roller R1 always presses the document bundle 51, a large stain is generated near the contact position of the document 51b with the call-in roller R1. In contrast to the adhesion of the dirt 55, in the configuration of the present invention, the adhesion of the dirt 55 can be reduced as shown in FIG.
[0059]
The lowering amount of the document tray 22 shown in FIG. 3B is an amount for separating the retrieving roller R1 from the uppermost surface of the document bundle 51. Specifically, the lowering amount of the retrieving roller R1 is lowered. , Is set to such an amount that the detection result of the attraction roller position detector S2 is turned off. Accordingly, the lowering amount is the minimum amount required to release the pressing force on the original bundle 51 by completely separating the loading roller R1 from the uppermost surface of the original bundle 51. In addition to suppressing the adhesion of dirt to the document 51b, it is possible to shorten the time until the document tray 22 is raised again and the next document can be taken out, thereby minimizing the time loss. .
[0060]
FIGS. 4, 5 and 6 are flowcharts showing the processing procedure for raising and lowering the document tray 22 by the control unit 41 of the scanner 1 according to the present invention. Hereinafter, with reference to these flowcharts, the operation of raising and lowering the document tray 22 of the scanner 1 configured as described above will be described.
[0061]
FIG. 4 is a flowchart showing a processing procedure of raising and lowering the document tray 22 by the control unit 41 from the time when the power is turned on until the document tray enters a standby state.
First, when a power switch (not shown) is turned on (step S11), the control unit 41 determines whether or not the output of the pull-in roller position detector S2 is turned on, that is, the optical path between the light emitting element S2a and the light receiving element S2b. Is determined (step S12), and if it is determined that the document is off (step S12: NO), the document tray 22 is started to be raised (step S13), and the process returns to step S12.
[0062]
If it is determined in step S12 that the output of the attraction roller position detector S2 has been turned on (step S12: YES), the control unit 41 starts lowering the document tray 22 (step S14), and detects the attraction roller position. It is determined whether or not the output of the device S2 has been turned off (step S15). If it is determined in step S15 that the switch is on (step S15: NO), the determination is repeated at an appropriate timing until it is determined that the switch is off.
If it is determined in step S15 that the output of the attraction roller position detector S2 has been turned off by continuing the lowering of the document tray 22 (step S15: YES), the control unit 41 controls the elevating motor 33 to a predetermined step. The original tray 22 is moved down to a first standby position by holding the original tray 22 by lowering the original tray 22 by a predetermined amount (step S16). In this state, the control unit 41 once ends the processing.
[0063]
As described above, the height position of the document tray 22 in the first standby state is set in advance by a service person or a user by operating the operation unit 46 in accordance with the number of documents frequently set on the document tray 22. It is the prescribed height.
[0064]
FIGS. 5 and 6 are flowcharts showing the processing procedure for moving up and down the document tray 22 of the control unit 41 from setting of a document to reading. However, FIG. 5 is a flowchart showing the processing procedure of raising and lowering the document tray 22 by the control unit 41 from the setting of the document until the document tray 22 enters a second standby state described later. Is in the first standby state (step S17).
[0065]
First, the controller 41 determines whether or not the output of the document detector S1 is ON, that is, whether or not a document is set on the document tray 22 (step S18). If it is determined that the document is turned off (step S18: NO), the determination is repeated at an appropriate timing until it is determined that the document is turned on in order to wait until a document is set on the document tray 22.
[0066]
If it is determined in step S18 that the output of the document detector S1 is ON (step S18: YES), the control unit 41 determines whether a predetermined time has elapsed after the determination in step S18 (step S19). If it is determined that the predetermined time has not elapsed (step S19: NO), the determination is repeated at appropriate timing until it is determined that the predetermined time has elapsed.
The predetermined time is set to give the user the time necessary to confirm or realign the original.
[0067]
When it is determined in step S19 that the predetermined time has elapsed (step S19: YES), the control unit 41 determines whether or not the output of the draw roller position detector S2 is turned off (step S20).
In this determination process, the call-in roller R1 is pushed up when the call-in roller R1 comes into contact with the document at the height position of the document tray 22 in the first standby state because the thickness of the document bundle is large. Then, the output of the attraction roller position detector S2 is turned on.
[0068]
If it is determined in step S20 that the document tray is on (step S20: NO), the control unit 41 starts lowering the document tray 22 (step S21), and returns to step S20.
In this way, by repeating the processing of steps S20 and S21, even if a predetermined number of documents or more are forcibly set on the document tray 22, the load roller R1 is moved beyond the predetermined document take-out position. It is checked whether the position is raised. If the feeding roller R1 is higher than a predetermined document take-out position, the document tray 22 is once lowered because there is a possibility that the feeding of the document may be hindered.
[0069]
When it is determined in step S20 that the output of the attraction roller position detector S2 has been turned off (step S20: YES), the control unit 41 starts moving the document tray 22 up (step S22). It is determined whether or not the output of the position detector S2 has been turned on (step S23).
When it is determined in step S23 that the document is turned off (step S23: NO), the control unit 41 pushes the document set on the document tray 22 by pushing up the call-in roller R1 to determine that the document is turned on. Repeat the judgment with.
[0070]
If it is determined in step S23 that the document tray 22 has been turned on by continuing to raise the document tray 22 (step S23: YES), the control unit 41 determines that the call-in roller R1 has reached a predetermined document take-out position, and 22 is stopped (step S24). As a result, the lifting of the document tray 22 ends, and the document tray 22 enters the second standby state (step S25).
[0071]
FIG. 6 is a flowchart showing the processing procedure for moving up and down the document tray 22 by the control unit 41 from the time when the document tray 22 enters the second standby state as described above until the reading of the document.
[0072]
After the document tray 22 enters the second standby state as described above, the control unit 41 determines whether or not a start signal has been input by operating the operation unit 46 (step S31). Is determined (step S31: NO), the determination is repeated at appropriate timing until it is determined that the input has been made.
If it is determined in step S31 that the start signal has been input (step S31: YES), the control unit 41 causes the feeding roller R1 and the separation roller R2 to feed the document (step S32), and the feed detector S3 detects the document. Then, it is determined whether or not the leading end is detected (step S33). If it is determined in step S33 that no detection has been performed (step S33: NO), the control unit 41 repeats the determination at an appropriate timing until it determines that detection has been performed.
[0073]
If it is determined in step S33 that the leading edge of the document is detected by the paper feed detector S3 (step S33: YES), the control unit 41 determines whether a predetermined time has elapsed after the determination in step S33 (step S33). (S34) If it is determined that the predetermined time has not elapsed (step S34: NO), the determination is repeated at appropriate timing until it is determined that the predetermined time has elapsed.
[0074]
If it is determined in step S34 that the predetermined time has elapsed (step S34: YES), the control unit 41 lowers and stops the document tray 22 by a predetermined amount as shown in FIG. (S35) Then, it is determined whether or not the trailing edge of the document is detected by the paper feed detector S3 (step S36). If it is determined in step S36 that the trailing edge of the document has not been detected (step S36: NO), the control unit 41 repeats the determination at an appropriate timing until it determines that the trailing edge of the document has been detected.
When it is determined in step S36 that the trailing end of the document is detected by the paper feed detector S3 (step S36: YES), the control unit 41 determines whether the output of the document detector S1 is off (step S36). S37).
[0075]
If it is determined in step S37 that the output of the document detector S1 is off (step S37: YES) because all the documents set on the document tray 22 are fed and lost, the document tray 22 is set to the first standby state. In order to return to the state, the control unit 41 returns the processing to step S12 in FIG. 4, and performs the processing after step S12.
On the other hand, when it is determined in step S37 that the output of the document detector S1 is ON because the subsequent document remains in the document tray 22 (step S37: NO), the control unit 41 determines whether the output roller R1 The document tray 22 is started to be raised so that the upper surface of the document bundle set on the document tray 22 is at a predetermined document take-out position (step S38). Then, the control unit 41 determines whether or not the output of the pull-in roller position detector S2 has been turned on (step S39). If it is determined that the output is off (step S39: NO), it is determined that the output has been turned on. The determination is repeated at an appropriate timing until the determination is made.
[0076]
If it is determined that the output of the call roller position detector S2 has been turned on in step S39 by continuing to raise the document tray 22 (step S39: YES), the control unit 41 determines whether the call roller R1 and the document have been turned on. Assuming that the upper surface of the bundle of documents on the tray 22 has reached the predetermined document take-out position, the movement of the document tray 22 is stopped (step S40), and the process returns to step S32 to feed the next document.
[0077]
When the document is forcibly pulled out of the document tray 22 after the second standby state in step S25, the output of the document detector S1 is turned off because there is no document on the document tray 22. In response to this, the control unit 41 returns the process to step S12 in FIG. 4, performs the processes after step S12, and sets the document tray 22 to the first standby state.
[0078]
Further, even if it is determined that the start signal has not been input in step S31 even after a predetermined time, for example, several minutes or more, has elapsed after the document tray 22 enters the second standby state, the control unit 41 may return the processing to step S12 in FIG. 4 and lower the document tray 22 to the first standby state by performing the processing after step S12. Further, the preset time may be set from the operation unit 46 within a range of, for example, one second to several seconds.
The process of returning the position of the document tray 22 from the second standby state to the first standby state is performed not only by the lapse of time but also by any key operation of the operation unit 46 as a trigger. Is also good.
[0079]
Further, in the present embodiment, the processing procedure until the document tray 22 reaches the height of the first standby state is controlled so as to be performed without using a detector that directly detects the height position of the document tray 22. However, the height of the document tray 22 may be controlled using a detector that directly detects the position of the document tray 22.
For example, a detector for detecting the lowest portion of the document tray 22 may be provided, and the document tray 22 may be set to the height of the first standby state based on the detection result of the detector. A detector for detecting the highest portion of the tray 22 may be provided. Generally, the height of the document tray 22 in the first standby state of the document tray 22 is the lowest point where the maximum stacking is possible, but may be set to an arbitrary halfway height.
[0080]
Embodiment 2
FIG. 7 is a schematic diagram illustrating a schematic configuration of a digital multifunction peripheral (hereinafter, referred to as a multifunction peripheral) 100 as an image forming apparatus including the sheet conveyance device according to the second embodiment of the present invention.
The multifunction peripheral 100 includes a reading unit 110 having the same configuration as the scanner 1 according to the first embodiment.
Image data obtained by reading by the reading unit 110 is sent to an image data input unit (not shown), subjected to predetermined image processing, and temporarily stored in a memory (not shown). Then, in response to an output instruction from the control unit 141, the image data is read from the memory and transferred to the laser writing unit 227 which is an optical writing device of the image forming unit 210 disposed below the reading unit 110.
[0081]
The image forming unit 210 includes a laser writing unit 227 and a cylindrical photosensitive drum 222, and further, around the photosensitive drum 222, a charger 229 for charging the photosensitive drum 222 to a predetermined potential, a photosensitive drum A developing unit 224 that supplies toner to the electrostatic latent image formed by the laser writing unit 227 on the 222 to make it visible, and a transfer unit that transfers the toner image formed on the surface of the photosensitive drum 222 to recording paper (transfer) A charger 225, a cleaner 226 for collecting excess toner remaining on the surface of the photosensitive drum 222, and a charge remover (charger, etc.) 223 for discharging the photosensitive drum 222 are provided in this order.
[0082]
A laser writing unit 227 includes a semiconductor laser light source that emits laser light in accordance with image data read from the memory or image data received from an external device by facsimile communication, and a polygon mirror that deflects laser light at a constant angular velocity. And an f-θ lens that corrects the laser beam deflected at a constant angular speed on the photosensitive drum 222 so as to be deflected at a constant angular speed.
In this embodiment, the laser writing unit 227 is used as the optical writing device, but a solid-scanning optical writing head unit using a light-emitting element array such as an LED and an EL may be used.
[0083]
The multifunction peripheral 100 further includes, beside the image forming unit 210, a fixing unit 217 for fixing the toner image transferred to the recording paper by heat and pressure, and a discharge for conveying the recording paper having passed through the fixing unit 217 to a discharge side. And a roller 219. Further, between the fixing unit 217 and the discharge roller 219, there is provided a switchback path 221 which extends downward and reverses the front and rear direction of the recording paper being conveyed. Further on the side of the discharge roller 219, a post-processing unit 260 having a vertically movable tray 261 capable of performing a stapling process or the like on the recording paper conveyed by the discharge roller 219 is provided.
[0084]
Further, a manual feed tray 254 for mounting recording paper is provided on a side surface of the multifunction peripheral 100 corresponding to a side opposite to the fixing unit 217 of the image forming unit 210. Further, below the image forming unit 210, a paper cassette 251 for accommodating recording paper, and temporarily accommodating the recording paper after an image is formed on one side when forming an image on both sides of the recording paper. A double-sided unit 255 and detachable paper cassettes 252 and 253 as a multi-stage paper feed unit 270 are provided in this order.
A transfer path 250 having one end near the transfer position of the transfer unit 225 of the image forming unit 210 and branching in the direction of each of the paper cassettes 251, 252, 253, the manual feed tray 254, and the duplex unit 255 is provided. Various rollers are provided at appropriate locations on the transport path 250. The duplex unit 255 is connected to the switchback path 221. The duplex unit 255 is configured to be replaceable with a paper cassette similar to the paper cassette 251.
[0085]
With the above-described configuration, the multifunction peripheral 100 reads image data obtained by reading an image of a document by the reading unit 110 on recording paper fed from the paper cassettes 251, 252, 253 or the manual feed tray 254, or An image is formed in the image forming unit 210 based on the image data received by facsimile communication, and after the image is fixed in the fixing unit 217, the recording sheet is conveyed to the switchback path 221 as necessary, and discharged by the discharge roller 219. The recording paper is guided to the post-processing unit 260, and after the predetermined post-processing is performed by the post-processing unit 260, the recording paper is discharged.
[0086]
In the multifunction peripheral 100 according to the second embodiment of the present invention, at least one of the paper cassettes 251, 252, 253 and the manual feed tray 254 is moved up and down in the same manner as the document tray 22 included in the scanner 1 of the first embodiment. It is configured to perform an operation.
For example, a case where the paper cassette 252 is configured to perform the same elevating operation as the document tray 22 will be described.
The paper cassette 252 is formed in a box shape opened upward, and has a lifting plate 272 at the bottom thereof. The elevating plate 272 is attached so as to be able to swing around the end (upstream side) opposite to the side (downstream side) where the transport path 250 is provided. Elevating means (not shown) is provided below the elevating plate 272, and the elevating plate 272 is moved up and down by the elevating means. The elevating means is constituted by the same members as the elevating plate 31, the elevating plate support shaft 32, the elevating motor 33, and the elevating mechanism 34 of the scanner 1 according to the first embodiment.
[0087]
An arm 125 having the same configuration as the arm 25 included in the scanner 1 of the first embodiment is provided at the end of the transport path 250 extending in the direction of the paper cassette 252. In the vicinity of the end of the transport path 250, a paper feed detector S103 similar to the paper feed detector S3 provided in the scanner 1 according to the first embodiment is provided. Is provided with a pair of opposed conveyance rollers R103 and R104.
[0088]
With such a structure, the lifting plate 272 moves up and down as follows, similarly to the lifting operation of the document tray 22 of the scanner 1 shown in FIG.
That is, in order to prepare for feeding of recording paper in synchronization with the image forming timing of the image forming unit 210, the elevating plate 272 is raised, and the bundle of recording paper on the elevating plate 272 pushes up the call-in roller R101, and the arm When the detection result of the pull-in roller position detector (not shown) provided at 125 is turned on, the top surface of the bundle of recording papers on the pull-in roller R101 and the elevating plate 272 reaches a predetermined recording paper take-out position. As a result, the lifting of the lifting plate 272 is stopped.
[0089]
Then, at the paper feed timing, as in the case of FIG. 3A, the intake roller R101 and the separation roller R102 are driven to rotate, and one recording sheet of the uppermost layer of the bundle of recording sheets is taken out. When a predetermined time elapses after the paper feed detector S103 detects that the leading end of the recording paper has passed, it is determined that the leading end portion of the recording paper is in a state of being sandwiched between the pair of rollers R103 and R104. 3B, the lifting plate 272 is lowered by a predetermined amount. That is, the lift plate 272 is lowered at the timing when the pair of transport rollers R103 and R104 start transporting the recording paper. Accompanying this, the attraction roller R101 descends. Since the lowering of the attraction roller R101 by a predetermined amount or more is prevented by a stopper (not shown), the pressing of the attraction roller R101 on the bundle of recording sheets is released.
As the elevating plate 272 descends in this manner, the dirt already attached to the lower surface (front surface) of the recording paper being fed and the upper surface (back surface) of the recording paper to be fed next. However, adhesion can be suppressed.
[0090]
After that, when the trailing edge of the recording paper is detected by the paper feed detector S103, the raising and lowering plate 272 is started to rise in preparation for taking out the next recording paper, as in FIG. 3C. Then, again, when the uppermost surface of the bundle of recording papers pushes up the pull-in roller R101 and the detection result of the pull-in roller position detector (not shown) is turned on, the lifting of the elevating plate 272 is stopped. Then, the next recording paper is fed in the same manner as the previous recording paper. The same operation is repeated for the succeeding recording paper.
This makes it possible to suppress the adhesion of dirt as described above when using a so-called backing paper having one surface used as the recording paper. Here, if the recording paper is new, it is not necessary to perform the operation of raising and lowering the elevating plate 272 before the above-described feeding of the next recording paper. Therefore, it is possible to switch whether or not to perform this operation. You may be able to.
[0091]
In Japanese Patent Application Laid-Open No. 59-92938, it is described that, in a paper feeding device, an elevating tray is moved up and down so that an invocation roller contacts the upper surface of a recording paper only at a paper feeding timing. In this prior art, a raising / lowering operation is performed so as to rise to the same height every time so that the paper feeding pressure becomes constant, and does not take into account the contamination of the recording paper due to the use of the backing paper. For this reason, the recording paper passes through the separation roller and descends on the elevating tray before reaching the transport roller, and the adhesion of dirt is suppressed, but stable transport cannot be performed.
[0092]
In the first and second embodiments, at the timing when the pair of transport rollers R3 and R4 (the pair of transport rollers R103 and R104) starts to transport the document 51a (recording paper), the original is driven by the call-in roller R1 (the call-in roller R101). The document tray 22 (elevating plate 272) is lowered to release the pressing on the bundle 51 (bundle of recording paper). However, the present invention is not limited to this, and other forms may be used. For example, a lifting unit controlled by a control unit 41 (control unit 141) for raising the attraction roller R1 (attraction roller R101) is provided, and the pair of transport rollers R3 and R4 (the pair of transport rollers R103 and R104) is used for the document. At the timing when the transport of the recording paper 51a (recording paper) is started, the raising roller R1 (the raising roller R101) may be raised by the raising means.
[0093]
【The invention's effect】
In the present invention, when the sheet body taken out of the sheet accommodating unit that has been raised so as to coincide with the sheet taking-out position starts to be conveyed by the conveying unit, for example, the sheet accommodating unit is lowered, and the sheet Since the contact with the body is released, the pressing force of the take-out roller or other take-out means on the contact surface between the sheet being fed and the sheet to be fed next stored in the sheet storage means. Accordingly, it is possible to minimize the contamination attached to one sheet member to the other sheet member. Further, the release of the contact with the sheet body by the take-out means is performed in synchronization with the timing at which the conveyance means starts to convey the sheet body taken out by the take-out means. Is performed.
[0094]
Further, according to the present invention, the amount by which the sheet accommodating means descends is an amount by which the sheet body accommodated in the sheet accommodating means is separated from the taking-out means such as a pull-in roller. Can be reduced to a necessary minimum amount at which the pressing force is released. In this way, at the contact surface between the sheet being fed and the sheet to be fed next, not only the dirt already attached to one sheet is suppressed from adhering to the other sheet, Since the sheet storage means in the lowered state can be raised and the transition time until the next sheet body can be taken out can be shortened as much as possible, the supply loss can be minimized.
[0095]
Further, according to the present invention, in the image reading apparatus, the contact force between the original being fed and the next original stored in the sheet storage and fed by the pressing force of the take-out roller or other extracting means. Accordingly, it is possible to minimize the contamination that has already adhered to the original being fed to the next original to be fed. As a result, it is possible to prevent the quality of reading the image of the document from being deteriorated.
Further, by providing such an image reading apparatus in the image forming apparatus, it is possible to prevent the quality of the formed image from deteriorating.
[0096]
Further, according to the present invention, in the image forming apparatus, the contact surface between the recording paper being fed and the recording paper that is stored in the sheet storage means and fed next is used to control the taking-out means such as an intake roller. The pressing force can minimize the contamination that has already adhered to one recording paper and adheres to the other recording paper. As a result, it is possible to prevent a decrease in image formation quality. This is particularly effective when a recording paper on which an image is formed or written on one surface, that is, a so-called backing paper, is used as the recording paper.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an overall mechanical configuration of a scanner according to the present invention.
FIG. 2 is a block diagram showing a functional configuration of a scanner according to the present invention.
FIG. 3 is a schematic side view illustrating a mechanical configuration around a document tray for describing an operation of lifting and lowering a document tray included in the scanner according to the present invention.
FIG. 4 is a flowchart illustrating a procedure for moving up and down the document tray by the control unit from when the power of the scanner according to the present invention is turned on until the document tray enters a standby state.
FIG. 5 is a flowchart illustrating a processing procedure for moving up and down the document tray by the control unit from setting of the document by the scanner according to the present invention until the document tray enters a second standby state.
FIG. 6 is a flowchart showing a procedure for moving up and down the document tray by the control unit from the time when the document tray of the scanner according to the present invention enters the second standby state until reading of the document.
FIG. 7 is a schematic diagram illustrating a schematic configuration of a digital multifunction peripheral according to Embodiment 2 of the present invention.
[Explanation of symbols]
1 Scanner
22 Document tray
33 lifting motor
34 lifting mechanism
41, 141 control unit
100 Digital MFP
251, 252, 253 Paper cassette
254 manual tray
272 lifting plate
R1, R101 Call-in roller
R2, R102 Separation roller
R3, R4, R5, R6, R7, R103, R104 Transport rollers
R8, R9 Registration roller

Claims (6)

Sheet storage means for stacking and storing a plurality of sheet bodies in the sheet storage means,
Lifting means for moving the sheet storage means up and down;
With a predetermined height position as a sheet taking-out position, taking-out means for taking out the sheet body from the uppermost layer in a state in which the sheet body is in contact with the upper surface of the sheet body contained in the sheet containing means,
Conveying means for conveying the sheet taken out by the takeout means to a predetermined position;
A sheet conveying device comprising: a control unit configured to control the elevating unit so that an upper surface of a sheet body accommodated in the sheet accommodating unit coincides with the sheet take-out position and raise the sheet accommodating unit.
The sheet conveying apparatus according to claim 1, wherein the control unit releases the contact of the take-out unit with the sheet body in synchronization with a timing at which the conveying unit starts conveying the sheet body. 2. The control device according to claim 1, wherein the control unit controls the elevating unit so that the sheet storage unit moves down in synchronization with a timing at which the conveying unit starts conveying the sheet body. 3. The sheet conveying device as described in the above. 3. The sheet conveying apparatus according to claim 2, wherein the amount by which the sheet accommodating means descends is an amount by which an upper surface of a sheet body accommodated in the sheet accommodating means is separated from the take-out means. In an image reading apparatus that takes in a sheet document and reads an image of the document by an image reading unit,
An image reading apparatus comprising: the sheet conveying apparatus according to claim 1 for conveying a sheet document to a position where an image is read by the image reading unit. In an image forming apparatus that forms an image on a sheet-shaped recording medium by an image forming unit,
An image forming apparatus, comprising: the sheet conveying device according to claim 1 for conveying a sheet-shaped recording medium to a position where an image is formed by the image forming unit. An image forming apparatus that reads an image on a sheet document to form an image,
An image forming apparatus comprising the image reading device according to claim 4 for reading an image of a sheet document.

Images