JP2021080061A - Image reading device - Google Patents

Abstract

To reduce a risk of rotation of a small size document which is not regulated by a document guide, when a plurality of documents having different width are mixed on a document tray.SOLUTION: An image reading device can selectively execute a normal mode for feeding a plurality of sheets of documents having the same document width and a different width sheets mixed and loaded mode for feeding a plurality of sheets of documents having different width, as a document feeding mode. When the normal mode is selected, a feeding roller is lifted and lowered when each of the documents loaded on a document tray is fed, and, when the different width sheets mixed and loaded mode is selected, the feeding roller is kept lowered during a period from the start of feeding of a first document of the plurality of sheets of documents loaded on the document tray to the completion of feeding of a final document.SELECTED DRAWING: Figure 4

Description

The present invention relates to an image reader that reads an image of a document.

Conventionally, an image reading device such as a scanner is a document feeding device (Auto Document Feeder, hereinafter referred to as ADF) that feeds documents placed on a document tray one by one toward a scanning position and reads an image of the document. ) Is provided. The document feeding device includes a paper feed roller for feeding the document placed on the tray, and the paper feed roller comes into contact with the upper surface of the placed document to start feeding the document.

The conventional image reading device has a configuration in which the position of the paper feed roller can be moved between the contact position where the paper feed roller is in contact with the upper surface of the document placed on the document tray and the separation position above the contact position. When the paper feed start command is input, the paper feed roller is moved to the contact position and rotation is started. As a result, the document is conveyed toward the transfer path. When the document is conveyed to the transport path, the paper feed roller is once raised to the separated position and moved to the contact position again at the timing of feeding the next document. As described above, Patent Document 1 proposes an ADF that executes control of repeatedly raising and lowering the paper feed roller each time one original document is fed.

By the way, the document feeding device has a so-called "different width mixed loading mode" in which a plurality of documents having the same paper width are fed in addition to a normal feeding mode in which a plurality of documents having the same paper width are fed. Some have a delivery mode called. In the different width mixed loading mode, since it is necessary to determine the paper width of the originals one by one, the productivity is reduced as compared with the normal feeding mode, and the feeding is performed.

Japanese Unexamined Patent Publication No. 2010-202358

In the different width mixed loading mode, as described above, a plurality of documents having different main scanning widths are mixed on the document tray. In this case, as shown in FIG. 11A, when the paper width regulation guide is set according to the width of the large-sized document, the small-sized document is not regulated by the guide.

When the elevating control of the paper feed roller described in Patent Document 1 is executed in this state, the document tends to rotate due to the reaction of the paper feed roller ascending or descending (FIG. 11B).

The present invention has been made in view of the above problems, and an object of the present invention is to provide a means for reducing the risk of rotation of a document placed on a document tray.

In order to solve the above problems, the image reading device according to one aspect of the present invention includes a document tray on which a document is placed, a feeding roller for feeding the document placed on the document tray, and the feeding roller. Separation means arranged downstream of the feeding roller in the feeding direction to separate the fed sheets one by one, and a width direction provided on the document tray and orthogonal to the feeding direction of the placed documents. A regulating plate for regulating the position in the above, an image reading unit for reading an image of a document separated by the separating means and conveyed through a transport path, and the feed roller are placed on the document tray. It has an elevating means for ascending / descending between an abutting position that abuts on the upper surface of the document, an elevating means that is above the abutting position and is separated from the document, and a control means that controls the elevating means. However, the image reading device has, as the document feeding mode, the first mode of feeding a plurality of documents having the same length in the width direction and the plurality of documents having different lengths in the width direction. The second mode of feeding can be selectively executed, and when the first mode is selected, the control means causes the feeding roller to feed one sheet of the mounted original. When the second mode is selected by moving to the contact position and the separation position, the period from the start of feeding the first document of the plurality of documents to the completion of feeding the final document. , The feeding roller is held at the contact position.

According to the present invention, the risk of rotation of the original can be reduced.

Schematic configuration diagram of the image forming apparatus Top sectional view of ADF Block diagram showing the control configuration of the image forming apparatus Flowchart showing the flow of job setting operation Flowchart showing the flow of feeding operation Timing chart during transport in different width mixed loading mode Timing chart during transport in thin paper setting mode Timing chart during transport in normal mode Diagram showing an example of the setting screen for mixed jobs The figure which shows an example of the document thickness setting screen A perspective view of the original on the original tray when mixed widths are mixed from above. Flowchart for detecting a width different from the size on the document tray in the document bundle in the transport path Top perspective view of the automatic document reader when feeding different width documents

[Example 1]
<Overall configuration of image forming device>
Hereinafter, a configuration example of the image reading device according to the present embodiment will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of an image forming apparatus 1000 including an ADF 100 as a document feeding apparatus of the first embodiment. The image forming apparatus 1000 includes an image reading unit 200 for reading an image of a sheet and an automatic document feeding apparatus (ADF) 100. Further, the image forming apparatus 1000 includes a controller 310 as a control means for controlling the operation of the ADF 100 and the image reading unit 200, and a main body side controller 300 for controlling the operation of the entire image forming apparatus 1000. The image reading unit 200 and the ADF 100 operate based on the signal input from the main body side controller 300. Although FIG. 1 shows a configuration in which the main body side controller 300 and the controller 310 are incorporated in the device main body 1000A, the controller 310 may be provided in the image reading unit 200.

The image forming apparatus 1000 includes an image forming engine 330 as an image forming means for forming an image on a sheet based on an image read by an image reading unit 200 and information input from an external information processing apparatus. In this embodiment, as the image forming engine 330, for example, one that forms an image of a colorant such as ink or toner on a sheet by an electrophotographic method, an inkjet method, an offset printing method, or the like can be used.

<Structure of image reader>
The image reading unit 200 will be described with reference to FIG. The image reading unit 200 includes an optical scanner unit 202 as a reading unit and a document mounting glass 209. The optical scanner unit 202 scans in the sub-scanning direction (arrow F, FIG. 1) at a constant speed, and reads the document S placed on the document mounting glass 209 line by line (fixed reading). Further, the optical scanner unit 202 moves so as to come to the center position of the surface glass facing member 211, and then optically reads the document S fed and conveyed by the ADF 100 (scanning). Further, the ADF 100 has an optical scanner unit 102. The optical scanner unit 102 optically reads the back surface of the document S read by the optical scanner unit 202 without inverting and transporting the document inside the ADF 100.

<ADF configuration>
Next, the ADF100 will be described with reference to FIG. As shown in FIG. 1, the ADF 100 includes a document tray 30 on which a bundle of documents S composed of one or more sheets is placed, and a document S downstream of the document tray 30 before the document S is fed. It has a separation upper roller 2 and a separation lower roller 3 and a feeding roller 1 that regulate the advancement of the. Inside the main body of the ADF 100, a presence / absence detection sensor 11 for detecting the presence / absence of the placed document S is provided below the document tray 30. The feeding roller 1 descends to the upper surface of the placed document and rotates to feed the document S. In the document S fed by the feeding roller 1, only one document S on the uppermost surface of the bundle of documents S is separated and conveyed by the action of the separation upper roller 2 and the separation lower roller 3. Then, the document S is directed to the scanning glass 201 by the drawing roller 4 and the drawing roller 5 via the transport path 50 and the lead roller 6 provided on the downstream side of the drawing roller 5 in the feeding direction of the document S. Will be transported.

The document S transported to the transport path 50 is transported to the image reading position on the scanning glass 201 by the lead roller 6 and the guide plate upstream roller 7. The LEDs 203a and 203b irradiate light when the document S passes between the scanning glass 201 and the surface glass facing member 211. The reflected light of the light emitted by the LEDs 203a and 203b is bent by the mirrors 204a, 204b and 204c and is incident on the surface image reading sensor 205. The surface image reading sensor 205 is composed of, for example, a sensor using an optical element such as a CMOS (Complementary charge-axis sensor) or a CCD (Charge Coupled Device). Then, the surface image reading sensor 205 reads the image of the document S line by line based on the incident light.

When reading only the image of the front surface of the document S, the document S conveyed by the guide plate downstream roller 8 is discharged to the discharge tray 32 by the discharge roller 10 via the back surface reading and transport roller 9. When scanning the image on the back surface of the document S, the document S is conveyed to the image reading position on the back glass facing member 101 after scanning the image on the front surface, and the image on the back surface of the surface scanned by the optical scanner unit 202 is displayed. It is read by the optical scanner unit 102. The LEDs 103a and 103b irradiate light when the document S passes through the back glass facing member 101. The reflected light of the light emitted by the LEDs 103a and 103b is bent by the mirrors 104a, 104b and 104c and is incident on the back surface image reading sensor 105. The back side image reading sensor 105 reads the back side image of the document S line by line by the incident light. The back surface image reading sensor 105 is also composed of a sensor using an optical element such as CMOS or CCD. The document S from which the image on the back surface has been read is discharged to the discharge tray 32 by the discharge roller 10.

When reading only the front surface image of the document, the document conveyed by the guide plate downstream roller 8 is conveyed to the output tray 32 by the paper ejection roller 10 while passing through the back surface reading and conveying roller 9.

The ADF in this embodiment can selectively execute at least two document feeding modes as a mode for feeding a plurality of documents placed on the document tray 30. The first document feeding mode is a normal mode in which a plurality of documents having the same document width are fed. In the normal mode, the paper feed roller 1 is moved between the contact position and the separation position each time one document is fed. That is, when the document is detected by the separation sensor 12, the paper feed roller 1 moves to a separated position, so that it is possible to prevent the document from being scratched.

The second document feeding mode is a mixed loading mode in which a plurality of documents having different document widths are fed. In the different width mixed loading mode, the position of the paper feed roller 1 is held at the contact position during the period from the paper feeding of the first sheet to the paper feeding of the final document. This reduces the risk of document rotation due to the raising and lowering of the paper feed roller 1.

<Structure of document tray>
Next, the configurations of the ADF 100 and the document tray 30 of this embodiment will be described with reference to FIG. FIG. 2 is an upper sectional view of the ADF 100. FIG. 2 shows a state in which A4 size paper is placed vertically on the document tray 30 (arrangement in which the length of the paper placed on the document tray 30 in the width direction is longer than the length in the feeding direction). .. As shown in FIG. 2, the document tray 30 is provided with regulating plates 31A and 31B which are paper width regulating guides for regulating the position in the width direction orthogonal to the feeding direction of the document. Further, the document tray 30 is provided with size detection sensors 17 and 18 for detecting the size of the placed document. The presence / absence of the sheet (manuscript S) placed on the document tray 30 is detected by the presence / absence detection sensor 11. Further, the movement of the mounted document in the width direction of the document S is restricted by the pair of restriction plates 31A and 31B, and the movement amount of the restriction plates 31A and 31B is detected by the document width detection sensor 809 (FIG. 3). Information on the amount of movement of the regulation plates 31A and 31B detected by the document width detection sensor 809 is input to the CPU 801. That is, the document width detection sensor 809 functions as the load width detection means of this embodiment. In this embodiment, the width direction of the document S is parallel to the axial direction of the feeding roller 1. Further, the regulation plates 31A and 31B can be moved until the distance between the regulation plate 31A and the regulation plate 31B in the width direction becomes a maximum of 300 mm.

On the document tray 30, the size detection sensors 17 and 18 detect the presence or absence of the document S at the detection position arranged upstream of the feeding roller 1 in the feeding direction of the document S. Specifically, in the feeding direction, the detection position of the size detection sensor 17 is arranged closer to the feeding roller 1 than the detection position of the size detection sensor 18. That is, the second sheet detecting means of this embodiment is the size detection sensor 18, and the detection position of the size detection sensor 18 is the first loading sheet detection position. Further, in this embodiment, the third sheet detection means is the size detection sensor 17, and the detection position of the size detection sensor 17 is the second load sheet detection position. The detection result of the document S by the size detection sensors 17 and 18 is input to the CPU 801. As described above, in the present embodiment, the first size detecting means for detecting the size of the loaded document is composed of the document width detection sensor 809 and the size detection sensors 17 and 18. The detection results of the document width detection sensor 809 and the size detection sensors 17 and 18 are the first detection results of this embodiment.

The document S fed from the document tray 30 separates the inside of the ADF 100 from the upper roller 2, the separation sensor 12, the extraction roller 4 as the transport roller pair of this embodiment, the extraction sensor 13, and the width detection sensors 14a, 14b, 14c. , 14d, and the drawing roller 5 in this order. In this embodiment, the length of the document S conveyed inside the ADF 100 in the width direction is detected by the width detection sensors 14a, 14b, 14c, 14d. In this embodiment, the width detection sensors 14a, 14b, 14c, 14d are provided at regular intervals in the width direction, respectively, and the detection result of the document S by the width detection sensors 14a, 14b, 14c, 14d is , Is input to the CPU 801. The CPU 801 determines the length of the document S in the width direction based on the detection results of the width detection sensors 14a, 14b, 14c, and 14d. The width detection sensors 14a, 14b, 14c, 14d cooperate to function as the second size detection means of this embodiment, and the detection results of the width detection sensors 14a, 14b, 14c, 14d are the second detection results of this embodiment. This is an example. The length of the document S in the feeding direction may be determined based on the time required for the document S to pass through the detection positions of the width detection sensors 14a, 14b, 14c, 14d in the feeding direction. .. In the following description, the width detection sensors 14a, 14b, 14c, 14d will be referred to as "width detection sensor 14" where it is not necessary to distinguish the width detection sensors 14a, 14b, 14c, 14d.

<Control configuration of image forming device>
Next, the control configuration of the image forming apparatus 1000 will be described with reference to FIG. FIG. 3 is a block diagram illustrating a control configuration of the image forming apparatus 1000. The controller 310 that controls the operation of the image reading unit 200 and the ADF 100 includes a CPU 801 as a calculation means, a ROM 802 as a storage area, and a RAM 803 as a working area of the CPU 801. A program for controlling the operation of the image reading unit 200 and the ADF 100 is stored in the ROM 802, and the CPU 801 loads this program from the ROM 802 and develops it on the RAM 803. Then, the operation of the image reading unit 200 and the ADF 100 is controlled by the CPU 801 executing the program developed on the RAM 803.

Further, the main body side controller 300 that controls the operation of the entire image forming apparatus 1000 includes a CPU 901 as a calculation means, a ROM 902 as a storage area, and a RAM 903 as a work area of the CPU 901. Further, the main body side controller 300 includes an image processing unit 905 configured by an ASIC or the like for handling image information, and an image memory 906 for storing image information. The ROM 902 stores a program that controls the overall operation of the image forming apparatus 1000, and the CPU 901 loads this program from the ROM 902 and develops it on the RAM 903. Then, the operation of the entire image forming apparatus 1000 is controlled by the CPU 901 executing the program developed on the RAM 903. That is, in this embodiment, the controller 310 is configured to operate based on the information input from the main body side controller 300. Therefore, the information and work data input from the operation display unit 904 and the external terminal are input from the main body side controller 300 to the controller 310 and stored in the RAM 803.

The separation motor 805 that rotationally drives the feed roller 1 and the separation upper roller 2 and the extraction motor 806 that rotationally drives the extraction roller 4 and the extraction roller 5 are connected to the CPU 801 via the bus 320. Further, the CPU 801 has a lead motor 807 that drives a reading lead roller 6, a guide plate upstream roller 7, a guide plate downstream roller 8, a back surface reading transport roller 9, and a discharge roller 10 via a bus 320. It is connected. Further, a pickup motor 808 for lowering (contacting) or raising (separating) the feeding roller 1 with respect to the upper surface of the document S is connected to the CPU 801. That is, the feeding roller 1 is configured to be in contact with and separated from the upper surface of the document S. The pickup motor 808 is connected to the feeding roller 1 via an elliptical cam (not shown). The feeding roller 1, the separation motor 805, and the pickup motor 808 cooperate to function as the feeding means of the present embodiment. Further, the separation roller 2 and the separation motor 805 cooperate with each other to function as the separation and transporting means of the present embodiment. Further, the extraction rollers 4 and 5 and the extraction motor 806 cooperate to convey the fed document to the downstream in the feeding direction.

<Original size judgment>
Here, a configuration for determining the size of the document S loaded on the document tray 30 in this embodiment will be described. As described with reference to FIG. 2, the document tray 30 is provided with size detection sensors 17 and 18. In the following, it is assumed that the document S is loaded on the document tray 30, and the position of the downstream end of the loaded document in the feeding direction will be described as the document tip position OP.

First, a configuration for determining the length of the document S loaded on the document tray 30 in the feeding direction in this embodiment will be described. As described with reference to FIG. 2, the document tray 30 is provided with size detection sensors 17 and 18, and the detection results of the size detection sensors 17 and 18 are input to the CPU 801 via the bus 320. Here, it is assumed that the distance from the document tip position OP to the size detection sensor 17 is 220 mm, and the distance from the document tip position OP to the size detection sensor 18 is 330 mm. At this time, the CPU 801 determines that the length of the document S in the feeding direction is less than 220 mm when the size detection sensor 17 is OFF and the size detection sensor 18 is OFF. Further, when the size detection sensor 17 is ON and the size detection sensor 18 is OFF, the CPU 801 determines that the length of the document S in the feeding direction is 220 mm or more and less than 330 mm. When the size detection sensor 17 is ON and the size detection sensor 18 is ON, the CPU 801 can determine that the length of the document S in the feeding direction is 330 mm or more. As described above, in the present embodiment, the CPU 801 has a range in which the length of the document S loaded on the document tray 30 in the feeding direction is set according to the combination of the detection results of the size detection sensors 17 and 18. To judge.

Next, a configuration for determining the length in the width direction of the document S loaded on the document tray 30 in this embodiment will be described. As described with reference to FIG. 2, the document tray 30 is provided with the regulation plates 31A and 31B, and the regulation plates 31A and 31B are connected to the document width detection sensor 809. The document width detection sensor 809 is composed of a variable resistor and an A / D converter, and converts a voltage analog value that changes due to the movement of the regulation plates 31A and 31B into 10-bit width data by the A / D converter. The detection result of the document width detection sensor 809 is input to the CPU 801 and the CPU 801 determines the length of the loaded document in the width direction based on the detection result of the document width detection sensor 809.

The CPU 801 determines the size of the original document based on the length of the original document S in the feeding direction and the length of the original document S in the width direction. In this embodiment, the manuscript S is grouped according to the size, and the size of the manuscript placed on the manuscript tray 30 is determined based on the length of the manuscript S in the feeding direction and the length of the manuscript S in the width direction. ..

<Configuration of image reading function>
Next, the configuration of the image reading function of the image reading unit 200 in this embodiment will be described. As shown in FIG. 3, the optical scanner unit 202 has a surface LED 203 and a surface image reading sensor 205 as a configuration for realizing the image reading function. The surface LED 203 and the surface image reading sensor 205 are connected to the CPU 801 via the bus 320. Further, the optical scanner unit 102 has a back surface LED 103 and a back surface image reading sensor 105. The back surface LED 103 and the back surface image reading sensor 105 are connected to the CPU 801 via the bus 320. When the CPU 801 starts the operation of reading the image data of the document S, the image of the document S is read by the back surface image reading sensor 105 and the front surface image reading sensor 205, and the read image is input to the CPU 801 as image data. .. The image data input to the CPU 801 is transferred to the image processing unit 810, and the image processing unit 810 performs shading processing and various filter processing. The image data processed by the image processing unit 810 is transferred to the main body side controller 300 via the communication unit 302. Further, the CPU 801 starts scanning the document with a vertical synchronization signal indicating a reading start position as a reference for starting scanning of the document S and a horizontal synchronization signal indicating a horizontal reference position as a reference for starting scanning of pixels for one line. Generate according to the timing. When the upper left pixel of the document S is set as the scanning start position of the document S, the CPU 801 sets the vertical synchronization signal with the reading pixel at the upper left end of the document S as the scanning start position and the horizontal reference position of the reading pixel at the left end of the document S. Generates a horizontal sync signal. The generated vertical synchronization signal and horizontal synchronization signal are transferred to the main body side controller 300 by the communication unit 302.

The main body side controller 300 transfers various data to and from the controller 310 via the command communication unit 301. The image data processed by the image processing unit 810 is input to the main body side controller 300 via the communication unit 302, and then transferred to the image processing unit 905. Then, after the image processing unit 905 performs image processing such as color determination for each pixel, the image data is stored in the image memory 906. Further, the main body side controller 300 includes an operation display unit 904 (operation unit) that displays the operation screen 90 and receives a user instruction via the operation screen. As shown in FIG. 19, the operation screen 90 is an example of a user interface that receives a user instruction and outputs a signal to the CPU 901. For example, the operation screen 90 can be displayed by using the touch panel as the operation display unit 904. it can. The CPU 901 receives a signal from the operation display unit 904 and starts a feed job, a read job, a print job, and the like. Upon receiving the job start signal from the CPU 901, the CPU 801 executes a document feeding operation by the ADF 100 and a document reading operation by the image reading unit 200. Although FIG. 3 shows a control block diagram when the operation display unit 904 is provided on the apparatus main body 1000A, even if the ADF 100 is provided with the operation display unit to display the operation screen 90. Good.

<Paper Roller Raise / Lower Control>
Next, the lowering timing change control of the paper feed roller 1 in this embodiment will be described with reference to FIGS. 1 to 12. Since it is the same when scanning both sides of a document, in this embodiment, an example of scanning one side of a document will be described.

FIG. 4 is a flowchart at the start of the reading job executed by the CPU 801. The program for executing this flowchart is stored in the ROM 802 in a format in which the CPU 801 can be executed, and is executed while holding the input data and the temporary data in the RAM 803. The read job is executed when the CPU 901 detects the selection of the start button of the operation display unit 904 and the CPU 901 sends a job start command to the CPU 801.

First, the CPU 801 determines whether or not the type of the mounted document is thin paper (S401). Thin paper is an example of a second type of paper having a smaller basis weight than plain paper (first type of paper). The thin paper setting is set by the user via the screen (FIG. 10) for selecting the media type displayed on the operation display unit 904. Specifically, the "thin" display button B2 on the screen of FIG. 10 is selected, and the "OK" button is selected to set the thin paper setting. The CPU 901 notifies the CPU 801 whether or not the job is to read the thin paper at the start of the reading job.

When there is a thin paper setting (S401Yes), the CPU 801 sets the paper feed roller control setting to an ascending / descending setting (S402). The paper feed roller control setting is a variable held in the RAM 803 and is referred to in the paper feed operation process of FIG. 5 described later.

By setting the paper feed roller control setting to the ascending / descending setting, the time for holding the document can be shortened, and wrinkles due to the feeding of a thin document can be prevented.

When there is no thin paper setting (S401No), the CPU 801 determines whether or not there is a different width mixed loading job setting (that is, a different width mixed loading mode setting) (S403). The different width mixed loading job setting is a setting of a job for reading a document when a bundle of documents has different documents in the main scanning direction. When the different width mixed loading mode is executed, it is necessary to determine the paper width of the originals one by one, so that the productivity is reduced and the paper is fed. Specifically, control is performed such that the transport speed is set slower than in the normal mode, or the document is temporarily stopped before the document reading position.

The different width mixed loading job setting is set by the user via the job type selection screen (FIG. 9) displayed on the operation display unit 904. Specifically, it is set by selecting the "different width" display button B1 and selecting the "OK" button.

The CPU 901 notifies the CPU 801 whether or not it is in the different width mixed loading mode at the start of the reading job.

In this embodiment, the "same width" display button and the "different width button" are displayed separately. However, it is also conceivable to display a selection screen on the operation display unit 904 for selecting "mixed loading setting" indicating that the originals have different sizes without distinguishing between "same width" and "different width". When such a display is made, it is determined that scanning of a document having a different width is set because the above "mixed loading setting" is selected.

Next, the CPU 801 sets the paper feed roller control setting to the lower setting (S404) when the different width mixed loading setting is provided (S403Yes). The paper feed roller control setting is a variable possessed by the RAM 803 and is referred to in the paper feed operation process of FIG. 5 described later.

By setting the paper feed roller control setting to the lower setting, the upper control of the paper feed roller 1 is not performed for documents other than thin paper. As a result, by bringing the paper feed roller 1 into contact with the document surface, it is possible to reduce the inclination of a small-sized document with different widths and mixed loading on the document tray. Further, since thin paper has low rigidity, it tends to be difficult for the original to rotate even if the paper feed roller is raised or lowered by controlling the mixed loading of different widths.

The CPU 801 sets the paper feed roller control setting to the ascending / descending setting (S405) when there is no different width mixed loading setting (that is, the normal feeding mode) (S403No).

The CPU 801 starts the paper feed control of S406 following S402, S404, and S405. The details of the paper feed control are shown in FIG.

FIG. 5 is a flowchart showing the flow of the feeding operation according to the present embodiment. The program that executes the processing of this flowchart is stored in the ROM 802 in a format that can be executed by the CPU 801 as in FIG.

First, the CPU 801 determines whether or not the paper feed start command has been received (S501). The paper feed start command is a command that the CPU 901 transmits to the CPU 801. The CPU 801 starts the document feeding operation when the paper feed start command is received (S501Yes). If the feeding start command has not been received (S501No), the CPU 801 waits for the document feeding operation until the paper feeding start command is received.

Next, the CPU 801 determines whether or not the lowering of the paper feed roller 1 has already been completed (S502). In the case of feeding the first sheet, since the paper feed roller 1 has not started to be lowered yet, the lowering of the paper feed roller 1 is not completed yet (S502No), but in the case of feeding the second and subsequent sheets. In some cases, as will be described later, the lowering of the paper feed roller 1 has already been completed.

When the CPU 801 determines that the lowering of the paper feed roller 1 is not completed (S502No), the CPU 801 starts lowering the paper feed roller 1 (S503). In the lowering control of the paper feed roller 1, the CPU 801 rotates the pickup motor 808, which is an elevating means, for a predetermined time or a predetermined number of pulses to change the rotation angle position of the elliptical cam (not shown). As a result, the paper feed roller 1 descends to the contact position where it comes into contact with the upper surface of the document placed on the document tray 30.

In this embodiment, an example in which the lowering control of the paper feed roller 1 is started when the paper feed start command is received has been described. However, the present invention is not limited to this, and for example, the lowering control is performed at the timing when the document presence / absence detection sensor 11 detects that the document has been placed on the document tray 30 before receiving the paper feed start command. You may do it.

Next, the CPU 801 waits for the lowering of the paper feed roller 1 to be completed (S504). When the pickup motor 808 rotates for a predetermined time or a predetermined number of pulses, the CPU 801 detects an interrupt signal and controls the pickup motor 808 to stop at a predetermined deceleration pulse. As a result, the amount of lowering of the paper feed roller 1 can be made constant.

Next, the CPU 801 rotates the separation motor 805 in order to start feeding the original (S505). When the separation motor 805 is rotated, the driving force of the separation motor 805 is transmitted to the paper feed roller 1 and the separation upper roller 2, and the paper feed roller 1 and the separation upper roller 2 are rotated. As a result, the manuscript is fed in the feeding direction.

Next, the CPU 801 determines whether or not the first sheet of the document bundle is conveyed (S506). When the first sheet of the document bundle is conveyed (S506 Yes), the extraction motor 806 and the lead motor 807 are rotated (S507).

As a result, all the transport rollers (FIG. 1, pull-out 1 roller 4, pull-out 2 roller 5, reading upstream lead roller 6, guide plate upstream roller 7, guide plate downstream roller 8, back surface reading transport roller 9, paper ejection roller 10) are removed. The document can be transported by rotating in the transport direction.

Next, the CPU 801 waits until the separation sensor 12 detects ON (with a document) (S508). Here, if the sensor does not detect the presence of the original within a predetermined time, it is determined that the transfer is abnormal, and it is determined that a jam has occurred and the transfer is stopped.

Next, when the sensor 12 is turned on after separation (S508Yes), the CPU 801 determines whether or not the paper feed roller 1 is set to rise or fall (S509).

The presence / absence of the ascending / descending setting is determined based on the setting information stored in the RAM 803 by S402 or S405 of FIG. 4 described above. Specifically, it is true (S509Yes) when the paper feed roller control setting stored in the RAM 803 is the “up / down setting”. On the other hand, when the paper feed roller control setting stored in the RAM 803 is "lower setting", it is false (S509No).

When the determination of the presence / absence of the ascending / descending setting of the paper feed roller 1 is true (S509Yes), the CPU 801 raises the paper feed roller 1 to the separated position (S510). The CPU 801 rotates the pickup motor 808 for a predetermined time or a predetermined number of pulses in order to raise the paper feed roller 1. As a result, the paper feed roller 1 is separated from the document surface via the elliptical cam.

When the presence / absence determination of the rise / fall setting of the paper feed roller 1 is false (S509No), the rise control of the paper feed roller 1 is not performed. As a result, the paper feed roller 1 is maintained at the contact position. That is, it is brought into contact with the document surface. According to this embodiment, it is possible to lengthen the time for holding down the original, and to reduce the inclination of the small-sized original placed on the original tray when the different width mixed loading is set. Further, in this embodiment, after the sensor 12 is turned on after the separation of S508, the paper feed roller 1 is raised in S510. As a result, wrinkles in the thin paper document can be reduced.

Next, the CPU 801 waits until the extraction sensor 13 detects that the extraction sensor 13 is ON (there is a document) (S511). Here, if the sensor does not detect the presence of the original within a predetermined time, it may be determined that the transfer is abnormal, and so-called jam detection for stopping the transfer may be realized by a known technique.

Next, the CPU 801 stops the separation motor 805 (S512). As a result, the second document can be fed one by one without being sent.

When the extraction sensor 13 of S511 is turned on, there is a sufficient distance to transfer the document by the conveying force of the extraction 1 roller 4, so even if the separation motor 805 is stopped in S512, the first document will not stop. ..

Next, the CPU 801 determines whether or not the paper feed roller 1 is set to rise or fall (S513).

The determination of the presence / absence of the ascending / descending setting is true (S513Yes) when the paper feed roller control setting on the RAM 803 set by S402 or S405 described above is the ascending / descending setting.

If the paper feed roller control setting on the RAM 803 set by S404 described above is a lower setting, it is false (S513No).

When the determination of the presence / absence of the ascending / descending setting of the paper feed roller 1 is true (S513Yes), the CPU 801 determines whether or not the thin paper setting is present (S514).

The thin paper setting is determined by referring to the variable in S401 described above, in which the CPU 901 has notified the CPU 801 whether or not the job is a thin paper setting job at the start of the reading job.

When the determination of the presence / absence of the ascending / descending setting of the paper feed roller 1 is false (S513No), the lowering control of the paper feed roller 1 by the timer is not performed.

When there is no thin paper setting (S514No), the CPU 801 starts a timer for setting the start timing of the lowering control of the paper feed roller 1 (S515). For example, when A4 is detected on the document tray, the counter is set to time up by transporting 210 [mm] of the length in the sub-scanning direction and aiming at the timing when the rear end of the document passes the paper feed roller 1. Set.

When the thin paper is set, the lowering control by the timer is not performed, and the lowering control of the paper feed roller is performed in S503 described above. As a result, after the originals have been reliably conveyed, the paper feed roller can be lowered to feed the next original, and wrinkles due to the feeding of thin originals can be prevented.

Next, the CPU 801 starts image reading (S516). In image reading, a counter threshold value for generating an image tip signal is set when the read sensor 15 is turned on, the motor pulse count of the lead motor 807 is counted, and the image is read when the threshold value is reached. It is control.

Next, the CPU 801 determines whether or not the paper feed roller 1 is set to rise or fall (S517). When the determination of the presence / absence of the ascending / descending setting of the paper feed roller 1 is true (S517Yes), the CPU 801 determines whether or not the thin paper setting is present (S518).

The thin paper setting is determined by referring to the variable in S401 described above, in which the CPU 901 has notified the CPU 801 whether or not the job is a thin paper setting job at the start of the reading job. When the determination of the presence / absence of the ascending / descending setting of the paper feed roller 1 is false (S517No), the time-up of the lowering control of the paper feed roller 1 is not waited.

When there is no thin paper setting (S518No), the CPU 801 waits for the time-up of the lowering control of the paper feed roller 1 by the timer set in S515 (S519).

The CPU 801 rotates the pickup motor 808 for a predetermined time in order to start the lowering of the paper feed roller 1 when the time is up (S519Yes) at the lowering timing of the paper feed roller 1 (S520). As a result, the elliptical cam rotates, and the paper feed roller 1 moves to the contact position.

Next, the CPU 801 waits for the sensor to turn off after separation (S521). Here, if the sensor does not detect the presence of the original within a predetermined time, it is determined that the transfer is abnormal and the transfer is stopped.

Next, the CPU 801 completes the image reading for one page when the required number of lines are read from the start of the image reading in S516 (S522). At this time, the CPU 801 notifies the CPU 901 of the completion of image reading for one page via the command communication unit 301.

Next, the CPU 801 determines whether or not there is a document on the document tray (S523). The CPU 801 determines that there is a document when the document presence / absence detection sensor 11 is ON. When the CPU 801 determines that there is a document on the document tray (S523Yes), the CPU 801 determines whether or not there is a paper feed start command for the next document (S501). By repeating the above control, a plurality of original sheets are fed.

When the CPU 801 determines that there is no document on the document tray (S523No), the CPU 801 waits for the document to be ejected (S524). The completion of ejecting the original can be realized by waiting until a predetermined time elapses after the output sensor 16 is turned off.

Next, the CPU 801 raises the paper feed roller 1 (S525). The raising of the paper feed roller 1 is controlled by rotating the pickup motor 808 for a predetermined time so as to separate the paper feed roller 1 from the document tray via an elliptical cam. Next, the CPU 801 stops the transfer motor (S526). The transport motors to be stopped are a pull-out motor 806 and a lead motor 807.

As a result, all the transfer rollers (Fig. 1 Extraction 1 roller 4, Extraction 2 roller 5, Reading upstream lead roller 6, Guide plate upstream roller 7, Guide plate downstream roller 8, Back surface reading transfer roller 9, Paper ejection roller 10) The rotation stops. Paper feed control is executed according to the above flowchart.

FIG. 6 shows a timing chart when different width mixed loading is set in the control flowcharts of FIGS. 4 and 5. The timing chart of FIG. 6 shows a transfer control signal and a state of driving the transfer motor when a document bundle composed of three documents is placed on the document tray 30. ON to OFF of the separation sensor 12 represents the transfer of one document. Then, with the passage of time, the document is detected in the order of the sensor 13, the lead sensor 15, and the paper ejection sensor 16 after the drawing.

In FIG. 6, as shown in the chart of the pickup vertical position, the paper feed roller 1 is in a paper feed state in which the contact position is maintained during the period from the first sheet paper feed to the completion of paper feed of the final paper. It shows that. The paper feed roller is lowered in S503 before feeding the first sheet, and the paper feed roller 1 is moved from the "(1) upper" position (separation position) to the "(2) lower" position (contact position). After the reading is completed, the paper feed roller 1 is raised to a separated position in S525. As a result, when the mixed document is conveyed, the paper feed roller is lowered on the document tray to hold the document on the document tray, thereby preventing the document from skewing.

In the mixed loading control of FIG. 6, the time to wait for the paper feed command from the CPU 901 is longer than that of the standard size document reading of FIG. 8 described later. As a result, the time t1 from when the sensor is turned off after separation to when the sensor is turned on after separation of the next document is longer than the time t3 shown in FIG.

FIG. 7 shows a timing chart when thin paper is set in the control flowcharts of FIGS. 4 and 5. Similar to FIG. 6, FIG. 7 also shows a transfer control signal and a state of driving the transfer motor when a document bundle composed of three documents is placed on the document tray 30.

In FIG. 7, the chart of the pickup vertical position raises the paper feed roller to the separated position when the sensor 12 is turned on after separation, and lowers the paper feed roller 1 to the contact position when the sensor 12 is turned off after separation. It is shown that. As shown in the chart of the pickup vertical position, the paper feed roller 1 moves from the "(1) upper" position (separation position) to the "(2) lower" position (contact) in S503 before feeding the first original. Move to position). Then, after the sensor 12 is turned on after the separation, the sensor 12 is moved to the "(3) upper" position (separation position) in S510. After that, after the sensor is turned off after separation, it is moved to the "(4) down" position in S503 when feeding paper. After the reading is completed, it moves to the separated position in S525. This makes it possible to prevent wrinkles at the tip of the original when the paper is thin.

FIG. 8 shows a timing chart in the control flowcharts of FIGS. 4 and 5 when plain paper and mixed loading of different widths are not set. It shows the transfer control signal and the driving state of the transfer motor when a document bundle composed of three documents is placed on the document tray 30.

In FIG. 8, the chart of the pickup vertical position shows that the paper feed roller is raised when the sensor is turned on after separation, and the paper feed roller 1 is lowered at a predetermined time after the sensor is turned on after separation.

Lower the paper feed roller in S503 before feeding the first sheet, move the paper feed roller from the "(1) top" position to the "(2) bottom" position, and after the sensor is turned on after separation, move the paper feed roller in S510. It has moved to the raised "(3) up" position. Then, after a predetermined time has elapsed from turning on the sensor after pulling out, the paper feed roller is lowered in S520 and moved to the "(4) lower" position. After the reading is completed, the paper feed roller is raised in S525.

As a result, the time t3 from when the sensor is turned off after separation to when the sensor is turned on after separation of the next document is shorter than the time t1 shown in FIG. 6 and the time t2 shown in FIG. By this control, the productivity of a standard document can be improved.

As described above, the image reading device in the present embodiment can selectively execute at least two feeding modes as the document feeding mode in which the plurality of documents placed on the document tray 30 are fed one by one. Is. The first document feeding mode is a normal mode in which a plurality of documents having the same document width are fed. The second document feeding mode is a mixed loading mode in which a plurality of documents having different document widths are fed. In the normal mode, the paper feed roller 1 is moved between the contact position and the separation position each time one document is fed. Specifically, since the paper feed roller 1 moves to a separated position when the tip of the document is detected by the separation sensor 12, it is possible to prevent the paper feed roller and the document surface from rubbing against each other and scratching the document. .. On the other hand, in the different width mixed loading mode, the position of the paper feed roller 1 is held at the contact position during the period from the first paper feed to the final paper feed. This makes it possible to reduce the risk of the document rotating on the document tray 30 as the paper feed roller 1 moves up and down.

Further, in the present embodiment, in the case of the thin paper transport mode for transporting the thin paper document which is easily scratched, the paper feed roller 1 is repeatedly moved up and down regardless of whether or not it is the different width mixed loading mode. This reduces damage to thin paper documents. With the above control, it is possible to achieve both the risk of rotation in the mixed loading mode of different widths and the transportation of thin paper documents.

<Other Examples>
In the first embodiment, an example in which the different width mixed loading mode or the normal mode is input via the operation display unit 904 has been described. However, in the above feeding mode, by detecting the width in the main scanning direction of the document in the transport path, it is possible to determine the mixed loading of different widths based on the detection result of the document width without input from the operation unit. is there.

In the upper cross-sectional view of the ADF 100 of FIG. 2, the document transport path width detection sensor 14 detects the document width passing through the transport path and can be used as a document size determination means in the main scanning direction of the document. If the image processing unit (A) 810 has an image processing mechanism capable of detecting the main scanning width of the original, it is also possible to determine that there is a different width original when the original width is acquired from the image. Is.

FIG. 12 is a flowchart of the difference width determination in the transport path executed by the CPU 801. By executing this flowchart after the sensor ON of FIG. 5S511 in the first embodiment is set to Yes, the document width can be detected at the timing when the document is on the document transport path width detection sensor 14.

The CPU 801 determines whether or not the main scanning length of the document tray and the width in the document transport path are different (S1201).

When the width information of the document tray top width detection sensor 809 and the ON / OFF combination of the document transport path width detection sensor 14 are different, the CPU 801 determines that the widths are different.

For example, as shown in FIG. 11A, a B5 size document is placed on the first sheet and an A4 size document is placed on the second sheet on the document tray. At this time, when the width information of the document tray upper width detection sensor 809 is detected as A4, when a B5 size document is actually conveyed, any one sensor of the main scanning width detection sensor 14 is turned off. (Fig. 13). FIG. 13 is a perspective view of the upper surface of FIG. 2, showing the position of the document at the timing when the A4 is placed on the document tray and the width of the B5 size document being conveyed is detected in the transfer path.

When transporting B5 size, the document transport path width detection sensors 14a, 14b, and 14c are ON (sensors shown in black), and the document transport path width detection sensor 14d is OFF, which is different from the width on the tray. Can be determined.

That is, by confirming that there is a difference between the width information of the document tray top width detection sensor 809 and the detection of the document transport path width detection sensor 14, it can be determined that documents having different main scanning widths are mixed. It is possible.

When the main scanning length of the document tray and the width in the document transport path are different from each other (S1201 Yes), the CPU 801 sets the paper feed roller control setting to the lower setting (S1202).

The paper feed roller control setting is a variable possessed by the RAM 803, and by referring to the paper feed roller control setting in FIG. 5 of the first embodiment during the ascending / descending control of the paper feed roller, it is possible to feed paper with the paper feed roller lowered.

According to the second embodiment, it is possible to determine that the originals have a plurality of sheets having different lengths in the width direction without designating the mixed loading of different widths by the operation display unit.

From the above, the image reading device in the present embodiment can selectively execute at least two feeding modes as a document feeding mode in which a plurality of documents placed on the document tray 30 are fed one by one. is there. The first document feeding mode is a normal mode in which a plurality of documents having the same document width are fed. The second document feeding mode is a mixed loading mode in which a plurality of documents having different document widths are fed. In the normal mode, the paper feed roller 1 is moved between the contact position and the separation position each time one document is fed. Specifically, since the paper feed roller 1 moves to a separated position when the tip of the document is detected by the separation sensor 12, it is possible to prevent the paper feed roller and the document surface from rubbing against each other and scratching the document. .. On the other hand, in the different width mixed loading mode, the position of the paper feed roller 1 is held at the contact position during the period from the first paper feed to the final paper feed. This makes it possible to reduce the risk of the document rotating on the document tray 30 as the paper feed roller 1 moves up and down.

Further, in the present embodiment, in the case of the thin paper transport mode for transporting the thin paper document which is easily scratched, the paper feed roller 1 is repeatedly moved up and down regardless of whether or not it is the different width mixed loading mode. This reduces damage to thin paper documents. With the above control, it is possible to achieve both the risk of rotation in the mixed loading mode of different widths and the transportation of thin paper documents.

The present invention is also realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiment is supplied to the system or device via a network or various storage media, and the computer (or CPU, MPU, etc.) of the system or device reads the program. This is the process to be executed.

1 Feeding roller 2 Separation upper roller 3 Separation lower roller 4 Pulling out 1 roller 5 Pulling out 2 roller 6 Reading upstream lead roller 7 Guide plate upstream roller 8 Guide plate downstream roller 9 Back side reading transport roller 10 Paper ejection roller 11 Document presence detection sensor 12 Separation sensor 13 Extraction sensor 14 Main scanning width detection sensor 15 Lead sensor 16 Paper output sensor 17 Document length sensor on tray 1
18 Tray document length sensor 2
30 Original tray 31 Original guide plate 32 Paper ejection tray 100 Automatic document feeding and transporting device (ADF)
101 Back side glass facing member 102 Back side optical scanner unit 103 Back side LED
104 Back side mirror 105 Back side image reading sensor 110 Back side shading white plate 200 Image reading unit 201 Front side scanning glass 202 Front side optical scanner unit 203 Front side LED
204 Surface mirror 205 Surface image reading sensor 209 Document mounting glass 210 Surface shading white plate 211 Surface glass facing member 301 Command transmitter 302 Image communication unit 300 Image processing controller 310 Document reading / ADF controller 801 CPU
802 ROM
803 RAM
804 Optical motor 805 Separation motor 806 Extraction motor 807 Lead motor 808 Pickup motor 809 Tray top width detection sensor 810 Image processing unit 901 CPU
902 ROM
903 RAM
904 Operation display unit 905 Image processing unit 906 Image memory 1000 Image reader

Claims (7)

The manuscript tray on which the manuscript is placed and the manuscript tray
A feeding roller that feeds the manuscript placed on the manuscript tray, and
A separating means that is arranged downstream of the feeding roller in the feeding direction and separates the sheets to be fed one by one.
A regulating plate provided on the document tray for regulating the position of the placed document in the width direction orthogonal to the feeding direction, and
An image reading unit that reads an image of a document separated by the separation means and conveyed through a transport path, and an image reading unit.
An elevating means for raising and lowering the feeding roller between a contact position that abuts the upper surface of a document placed on the document tray and a separation position that is above the contact position and away from the document. When,
A control means for controlling the elevating means and
Have,
The image reader is
As the document feeding mode, a first mode for feeding a plurality of documents having the same length in the width direction, a second mode for feeding a plurality of documents having different lengths in the width direction, and a second mode. Can be selectively executed,
When the first mode is selected, the control means moves the feeding roller to the contact position and the separation position each time one sheet of the mounted document is fed, and the second mode. When is selected, the feeding roller is held at the contact position during the period from the start of feeding the first original of the plurality of originals to the completion of feeding of the final original. Image reader. It has an operation unit that accepts user instructions.
The image reading device according to claim 1, wherein the document feeding mode is set via the operation unit. As the type of the original placed on the original tray, it is possible to select the first type of original and the second type of original having a smaller basis weight than the first type.
The image reading device according to claim 1 or 2, wherein the control means raises and lowers the feeding roller regardless of the document feeding mode when the second type of document is selected. The image reading device according to claim 1, wherein the document feeding mode is selected according to the detection result of the width of the document in the transport path. Further having a separation sensor for detecting a document downstream in the feeding direction of the separation means,
Any one of claims 1 to 4, wherein in the first mode, the control means raises the paper feed roller to the separated position based on the detection of the tip of the document by the separation sensor. The image reading device according to item 1. The fifth aspect of claim 5, wherein in the first mode, the control means lowers the paper feed roller to the contact position based on the detection of the rear end of the document by the separation sensor. Image reader. A drawing roller for transporting the original, which is arranged downstream of the separating means in the feeding direction,
A post-drawing sensor for detecting a document and a post-drawing sensor arranged downstream of the pulling roller in the feeding direction.
Have,
The first mode is characterized in that the control means lowers the paper feed roller to the contact position when a predetermined time elapses after the tip of the document is detected by the sensor after the extraction. The image reading device according to 5.

Images