JP2023179353A - Sheet feeding device, automatic sheet feeding device, image reading device, and image forming device - Google Patents

Abstract

To suppress a situation that positioning work of a regulating section cannot be completed before falling into a contacted state where a sheet bundle on a placing portion and a feeding member come into contact with each other.SOLUTION: A sheet feeding device including a stacking portion on which a sheet bundle is placed, a feeding member that contacts and feeds sheets placed on the stacking portion, and a regulating section that is configured to be movable in a sheet width direction and regulates a position of the sheet bundle on the stacking portion in a sheet width direction, comprises: switching means 105 for switching from a separation state where the sheet bundle and the feeding member are separated to a contact state where the sheet bundle and the feeding member are in contact without waiting for instructions to start feeding, after the sheet bundle is placed on the stacking portion; size identifying means 116a to 116d for identifying a sheet width direction size of the sheet bundle; and timing changing means 150 for delaying a timing to complete switching from the separation state to the contact state when the sheet width direction size identified by the timing changing means is smaller than a predetermined size compared to when it is equal to or larger than the predetermined size.SELECTED DRAWING: Figure 3

Description

The present invention relates to a sheet feeding device, an automatic sheet feeding device, an image reading device, and an image forming device.

Conventionally, the loading section is configured to be movable in the sheet width direction, including a loading section on which a sheet bundle is loaded, a feeding member that feeds the sheets by contacting with the sheets loaded on the loading section, and A sheet feeding device is known that includes a regulating section that regulates the position of the upper sheet bundle in the sheet width direction.

For example, Patent Document 1 discloses a sheet feeding device including a document regulating plate (regulating section) that regulates the widthwise position of a document (sheet) placed on a document tray (placing section). There is. In this sheet feeding device, the document tray is configured to be movable up and down by a lifting device (switching device), and before the document is placed on the document tray, it is placed in a predetermined lowered position (the upper surface of the document and the (member) is in a separated state). When the original is placed on the original tray, the size of the original is detected by the detection means, and if the detection result of the detection means is the standard size, it is determined that the original is placed properly on the original tray. be done. In this case, the document tray starts to rise after a predetermined time has elapsed after the document is placed, and the document tray assumes a predetermined raised position (a contact state where the top surface of the document and the pick-up roller are in contact). . Thereafter, by inputting a document reading start signal (feeding start instruction), feeding of the document is immediately started. On the other hand, if the detection result of the detection means is not the standard size, it is determined that the document is not properly placed on the document tray. In this case, the raising of the document tray is not started until the document reading start signal is input.

In conventional sheet feeding devices, before the sheet stack on the loading unit and the feeding member come into contact with each other, the regulating section must be positioned to match the width of the sheet stack (regulating section alignment work). Sometimes I couldn't complete it.

In order to solve the above-mentioned problems, the present invention provides a loading section on which a sheet bundle is placed, a feeding member that feeds the sheets by contacting with the sheets placed on the loading section, and a feeding member that feeds the sheets in the sheet width direction. a regulating section configured to be movable to and regulating the position of the sheet bundle on the sheet stacking section in the sheet width direction, the sheet feeding device having the sheet stack placed on the loading section. After that, without waiting for a feeding start instruction, the state changes from a separated state in which the sheet stack on the loading section and the feeding member are separated, to a contact state in which the sheet stack on the loading section and the feeding member contact each other. a switching means for switching to a contact state, a size specifying means for specifying a size in a sheet width direction of the sheet bundle to be placed on the loading section, and a size in the sheet width direction specified by the size specifying means is smaller than a predetermined size. When the size is equal to or larger than the predetermined size, the apparatus further comprises a timing changing means for delaying the timing of completing the switching from the separated state to the contact state than when the predetermined size is larger than the predetermined size.

According to the present invention, the positioning of the regulating section to match the width of the sheet stack (positioning work of the regulating section) cannot be completed before the sheet stack on the loading section and the feeding member come into contact with each other. It is possible to suppress the occurrence of such a situation.

FIG. 1 is an explanatory diagram showing a schematic configuration of a copying machine in an embodiment. FIG. 2 is an explanatory diagram showing a schematic configuration of an ADF in the copying machine. FIG. 3 is a block diagram showing the configuration of a control section of the ADF. FIG. 3 is a plan view schematically showing a movable table of a document table in the ADF. FIG. 3 is a plan view showing a state in which a bundle of small-sized originals P whose width direction size is smaller than a predetermined size is set on the same original table. A flowchart showing the lifting operation of the movable table (bottom plate). In the embodiment, a graph showing an example of the relationship between the width between two side fences and the waiting time until the movable table (bottom plate) starts rising. 12 is a graph showing another example of the relationship between the width between two side fences and the waiting time until the movable table (bottom plate) starts rising in the embodiment. FIG. 3 is an explanatory diagram showing an example of an operation screen for a user to input the width direction size of a document bundle. 7 is a graph showing an example of the relationship between the width between two side fences and the rising speed of the movable table (bottom plate) in Modification 1. 7 is a graph showing another example of the relationship between the width between two side fences and the rising speed of the movable table (bottom plate) in Modification 1. 10 is a flowchart showing the raising operation of the movable table (bottom plate) in Modification 1. 12 is a flowchart showing the raising operation of the movable table (bottom plate) in Modification 2.

Hereinafter, one embodiment of the present invention will be described using the drawings.
Here, an example will be shown in which the sheet feeding device according to the present invention is applied to an automatic document feeder (ADF) as an automatic sheet feeding device, an image reading device, and an image forming device.

FIG. 1 is an explanatory diagram showing a schematic configuration of a copying machine 1 as an image forming apparatus in this embodiment.
The copying machine 1 includes an automatic document feeder (ADF) 100, a feeding section 2, and an image forming section 3.

The feeding unit 2 includes feeding cassettes 21 and 22 that store transfer papers (sheets) as recording materials of different sizes, and various types of feeding cassettes 21 and 22 that accommodate transfer papers (sheets) as recording materials of different sizes, and various types that transport the transfer papers stored in the feeding cassettes 21 and 22 to the image forming unit 3. It has a feeding means 23 consisting of a roller.

The image forming section 3 includes an exposure device 31, photosensitive drums 32 for each of four colors, a developing device 33, a transfer belt 34, and a fixing device 35. The image forming section 3 exposes each photoreceptor drum 32 to light using an exposure device 31 based on the image data of the document read by the image reading section provided inside the ADF 100, thereby forming a latent color of each color on each photoreceptor drum 32. form an image. Thereafter, toner of each color is supplied to each photoreceptor drum 32 by the developing device 33 of each color, and the latent image on each photoreceptor drum 32 is developed to form a toner image. Then, the image forming section 3 transfers the toner image of each photoreceptor drum 32 onto the recording paper supplied from the feeding section 2 by the transfer belt 34, and then transfers the toner of the toner image transferred onto the recording paper to a fixing device. 35 to fix the color image on the recording paper.

FIG. 2 is an explanatory diagram showing a schematic configuration of an automatic document feeder (ADF) 100 that functions as an image reading device.
The ADF 100 is provided at the top of the copying machine 1, as shown in FIG. The ADF 100 first aligns the fed originals with an original setting part A where a bundle of originals is set, and a separation and feeding part B which separates and feeds the originals one by one from the set bundle of originals. a registration section C that pulls out and conveys the original after alignment, and a turning section D that turns the conveyed document so that the surface of the document is directed toward the reading side (downward in the figure) by the first image reading section 131. A first reading and conveying section E reads the front side image of the document from below the contact glass 4 by the first image reading section 131, and a second reading conveyance section E reads the back side image of the document after the front side image has been read by the second image reading section 132. It includes a reading conveyance section F, a paper discharge section G for discharging the originals from which front and back images have been read out of the machine, and a stacking section H for stacking and holding the discharged documents.

In the document setting section A, one document or a bundle of two or more documents (hereinafter collectively referred to as a "manuscript bundle") to be read is set. The document bundle is set on a document table 120 that includes a movable table 121 and serves as a placement section.

In this embodiment, a contact glass 4 made of a light-transmitting member is provided on the top surface of the main body of the copying machine 1, and an ADF 100 is provided adjacent to the contact glass. The ADF 100 can be opened and closed via a hinge mechanism to open and close the contact glass 4.

The ADF 100 is compatible with both a sheet-through reading method (automatic transport mode) and a fixed document reading method (pressing plate mode). In the sheet-through reading method, one or both of the first image reading section 131 and the second image reading section 132 reads the image while the first image reading section 131 is fixed and the document to be read is conveyed at a predetermined speed. Read. In the fixed document reading method, a document to be read is placed on the contact glass 4 and the first image reading section 131 is moved along the contact glass 4 to read the image.

In the copying machine 1 of the present embodiment, an automatic transport mode (ADF mode) in which a document is read using the fixed document reading method described above, and It is configured such that an operation mode such as a pressure plate mode in which a document is read using a sheet-through reading method can be set as desired.

FIG. 3 is a block diagram showing the configuration of the control section of the ADF 100.
As shown in FIG. 3, the ADF 100 includes various drive units 101 to 105 that drive the document feeding operation (original conveyance operation) in each mechanism unit A to H, and the operation of the drive units 101 to 105. A control section 150 consisting of a circuit for controlling operations is also provided.

The control unit 150 supplies power to each unit installed in the ADF 100 and controls each unit installed in the ADF 100 based on a control signal transmitted from the main body control unit 6 provided in the main body of the copying machine 1. Implement control over

When reading a document image using the fixed document reading method, the document is set on the contact glass 4 and the ADF 100 is closed. A pressure plate is provided at the bottom of the ADF 100 for pressing the original against the contact glass 4 when reading the original using the fixed original reading method. When the ADF 100 is placed in a closed state and an original reading instruction operation is performed on the operation unit 5, the original is read while moving the first image reading unit 131 in the left-right direction in FIG. Note that in the fixed original reading method, for example, each time one A4-sized original is read, a gate signal is transmitted from the control unit 150 to the first image reading unit 131 to perform reading control.

When reading a document image using the sheet-through reading method, a stack of documents is set on a document table 120 (placing section) including a movable table 121 with the document surface (first surface) facing upward. Furthermore, the width direction of the document bundle (direction perpendicular to the document conveyance direction) is regulated by a side fence 122 serving as a regulating section, and the side fence 122 is positioned (aligned) in accordance with the width of the document bundle. The fact that the document bundle has been set (set state) is detected by the document set sensor 115 provided on the movable table 121, and is transmitted to the main body control section 6 via the interface (I/F).

The movable table (bottom plate) 101 is supported such that the rear end of the movable table 121 (backward in the document feeding direction) is rotatable around a rotation shaft 121a. The movable table 121 is configured to be able to move up and down at its leading end (front in the document feeding direction) by being rotated around a rotation shaft 121a by the bottom plate lift motor 105.

Before the original is placed on the original table 120, the movable table 121 of the original table 120 is located at the home position (lowered position). With the movable table 121 at the home position, the user places a stack of originals on the original table 120. At this time, the top surface of the document bundle on the movable table 121 at the home position is in a separated state away from the pickup roller 141.

When the document set sensor 115 detects that a document has been set, the control section 150 rotates the bottom plate lift motor 105 in the normal direction so that the top surface of the document bundle on the movable table 121 is connected to the pickup roller 141 as a feeding member. The movable table 121 is raised so that it comes into contact. When the movable table 121 rises and the pickup roller 141 is pushed up by the upper surface of the document bundle on the movable table 121, this is detected by the table rise sensor 118. The control unit 150 that receives this detection signal stops driving the bottom plate lifting motor 105, so that the movable table 121 is stopped at an appropriate position.

That is, the table rise sensor 118 is a sensor for detecting that the movable table 121 has reached an appropriate position and for maintaining the upper surface of the document bundle at an appropriate feeding height. Specifically, when the table rise sensor 118 turns ON, the movable table 121 stops rising, and then, by repeating document feeding, the upper surface position of the document bundle lowers, and when the table rise sensor 118 turns OFF, the movable table 121 stops moving. Raise the table 121 again. Then, when the table rise sensor 118 is turned ON again, the movement of the movable table 121 is stopped. By repeating such control operations, the top surface position of the document bundle (height of the topmost document) is maintained within a height range suitable for document feeding.

Note that instead of raising and lowering the movable table 121, the table may be fixed and the pickup roller may be raised and lowered. In addition, a pickup roller that moves up and down is provided below the fixed table so that the bottom surface of the document stack on the table where the document is set can be fed by the feeding member. It may also be brought into contact with the lowest surface of the stack of originals above the insertion table. In addition, the table and a pickup roller protruding from the table are raised together so that the lowermost surface of the document bundle on the table where the document is set can be fed by the feeding member, and the uppermost surface of the raised document bundle is raised by the upper surface regulating member. Alternatively, the upper surface regulating member may be lowered and brought into contact with the uppermost surface of the document bundle without raising and lowering the integrated table and the pickup roller protruding from the table. In this case, the contact state in which the pickup roller and the document are in contact is a state in which the top surface of the document stack is in contact with the top surface regulating member and there is enough contact pressure to allow the pickup roller to properly feed the document, and the document is separated. The separated state is a state in which the top surface of the document bundle does not come into contact with the upper surface regulating member and the contact pressure is so light that the pickup roller cannot properly feed the document and slips.

When all the original bundles set on the original table 120 have been fed, the original set sensor 115 is turned off, and the control unit 150 reverses the bottom plate lifting motor 105 to move the next original bundle onto the original table 120. The movable table 121 is lowered to the home position so that it can be set to the home position. In this embodiment, a bottom plate home position sensor 117 is provided to detect whether the movable table 121 is at the home position, and the control unit 150 is configured to be able to confirm whether the movable table 121 is at the home position. It has become.

When the top surface of the document bundle on the movable table 121 is in contact with the pickup roller 141 and a document reading instruction operation (feeding start instruction) is performed on the operation section 5, an instruction is sent from the main body control section 6 via the interface. , a document feeding signal (feeding start signal) is transmitted to the control unit 150. As a result, the feeding operation is started, and while the top surface of the document bundle on the movable table 121 is maintained at an appropriate feeding height, the pickup roller 141 is rotated by the normal rotation of the feeding motor 102, and the document is Several documents (ideally one document) are picked up on the table 120. The direction of rotation at this time is the direction in which the uppermost document is conveyed forward in the feeding direction. The separation roller pair 142 is composed of a feeding roller 142A and a reverse roller 142B opposing the feeding roller 142A. The normal rotation of the motor 102 drives the rotation in a direction opposite to the feeding direction.

The document separated into single sheets by the separation roller pair 142 is further conveyed by the feeding roller 142A, and after the leading edge is detected by the abutment sensor 111, the document advances further and abuts against the stopped pullout roller pair 143. Thereafter, the document is conveyed a predetermined distance from the detection timing of the abutment sensor 111, so that the leading edge of the document is pressed against the pull-out roller pair 143 with a predetermined amount of deflection. In this state, by stopping the feeding motor 102, the driving of the feeding roller 142A that is conveying the document is stopped.

When the leading edge of the document is detected by the abutting sensor 111, the control unit 150 rotates the pickup motor 101 and retracts the pickup roller 141 from the top surface of the document. Therefore, the document is conveyed only by the conveyance force of the feed roller 142A of the separation roller pair 142. Through this operation, the leading edge of the document enters the nip portion of the pair of pullout rollers 143, and alignment (skew correction) of the leading edge is performed. The pull-out roller pair 143 has a skew correction function and is a roller for conveying the skew-corrected document after separation to the intermediate roller 144, and is driven by the reverse rotation of the feeding motor 102. Further, when the feeding motor 102 is reversed, the pullout roller pair 143 and the intermediate roller 144 are driven, but the pickup roller 141 and the feeding roller 142A are not driven.

The length of the document in the conveyance direction is configured to be detected from motor pulses by detecting the leading and trailing ends of the document with an abutment sensor 111. When the document is transported from the registration section C to the turn section D by driving the pull-out roller pair 143 and the intermediate roller 144, the transport speed in the registration section C is higher than the transport speed in the first reading transport section E. By setting this, the processing time for sending the document to the first reading and conveying section E can be shortened. When the leading edge of the document is detected by the reading entrance sensor 112, before the leading edge of the document enters the nip portion of the pair of reading entrance rollers 145, deceleration is started to make the document conveyance speed the same as the reading conveyance speed. The reading motor 103 is driven to rotate normally to drive the reading entrance roller pair 145, the first reading exit roller 146, and the second reading exit roller 147.

When the leading edge of the document is detected by the registration sensor 113, the control section 150 temporarily stops the document before the first reading and conveying section E, and sends a registration stop signal to the main body control section 6 via the interface. Next, when the control unit 150 receives a reading start signal from the main body control unit 6, the control unit 150 increases the speed so that the leading edge of the document, which has been stopped in registration, reaches a predetermined conveyance speed by the time it reaches the first reading conveyance unit E. and transport it. The control unit 150 transmits an effective image area in the sub-scanning direction on the first side to the first image reading unit 131 at the timing when the leading edge of the document detected by the pulse count of the reading motor 103 reaches the first reading conveyance unit E. Send a gate signal indicating the This gate signal is transmitted until the trailing edge of the document passes through the first reading and conveying section E.

In the case of single-sided reading, the document that has passed through the first reading and conveying section E passes through the second reading and conveying section F and is conveyed to the paper discharge section G. At this time, when the paper ejection sensor 114 detects the leading edge of the document, the control unit 150 drives the paper ejection motor 104 in normal rotation to rotate the paper ejection roller pair 148 . Further, the control unit 150 counts the pulses of the paper ejection motor 104 after the leading edge of the document is detected by the paper ejection sensor 114, and starts the paper ejection motor 104 immediately before the trailing edge of the document comes out of the nip between the pair of paper ejection rollers 148. The drive speed of 104 is reduced to control the document to be discharged onto the paper discharge tray of the stack section H so that it does not fly out.

In the case of double-sided reading, the control unit 150 counts the pulses of the reading motor 103 after detecting the leading edge of the document that has passed through the first reading and conveying unit E using the paper discharge sensor 114. Next, the control unit 150 transmits a gate signal indicating the effective image area in the sub-scanning direction to the second image reading unit 132 at the timing when the leading edge of the document reaches the second reading and conveying unit F. This gate signal is transmitted until the trailing edge of the document passes through the second reading and conveying section F. Thereafter, the original that has passed through the second reading and transport section F is transported to the paper discharge section G.

Next, the side fence 122 as a regulating portion disposed on the document table 120 of the ADF 100 will be described.
FIG. 4 is a plan view schematically showing the movable table 121 of the document table 120 in this embodiment.
FIG. 5 shows a state in which a document bundle P of small-sized documents whose size in the sheet width direction is smaller than a predetermined size, that is, smaller than a predetermined size, is set on the document table 120 in this embodiment (side fence alignment FIG. 3 is a plan view showing a state in which the work is completed.

The side fence 122 arranged on the document table 120 of the ADF 100 in this embodiment regulates the widthwise position of the document bundle P placed on the document table 120. The document table 120 of the ADF 100 may be of an edge reference type in which the edge position on one side in the width direction is used as the reference for the set position of the document bundle P, or a center position in which the center position in the width direction is taken as the reference for the set position of the document bundle P. A standard method may also be used. In this embodiment, a central reference method is adopted.

In the case of the edge reference method, a fixed fence is provided on the document table 120 as a fixed regulating portion that comes into contact with one side of the document bundle P in the width direction. The side fence 122 is configured to abut on the other side of the document bundle P in the width direction. In this case, when setting the document stack P on the document table 120, the document stack P is placed between the fixed fence and the side fence 122, and then the side fence 122 is placed at the other end in the width direction of the document stack P. The side fence 122 is moved along the document width direction until it comes into contact with the side. As a result, the widthwise position of the document bundle P is regulated by the fixed fence and the side fence 122.

In the case of the central reference method, as shown in FIGS. 4 and 5, two side fences 122 are provided on the document table 120 as regulating members that abut on one side and the other side of the document bundle P in the width direction, respectively. These two side fences 122 are configured to be movable in the document width direction in conjunction with each other so that the distance between each side fence 122 and the center position in the document width direction is always constant. In this case, when setting the document stack P on the document table 120, the document stack P is placed between the two side fences 122, and then the document stack P is sandwiched between the two side fences 122 from the width direction. The two side fences 122 are moved along the document width direction until . As a result, the widthwise position of the document bundle P is regulated by the two side fences 122.

In this embodiment, the movable table 121 of the document table 120 is provided with a guide groove 123 that guides the side fence 122 to move along the document width direction. As shown in FIGS. 4 and 5, the guide groove 123 extends along the document width direction and opens onto the movable table 121. A guide pin provided at the lower part of the side fence 122 is fitted into the guide groove 123, so that the side fence 122 can move along the guide groove 123 in the document width direction.

Further, in the movable table 121 in this embodiment, four side fence width sensors 116a to 116d are arranged along the guide groove 123. The side fence width sensors 116a to 116d are constituted by optical sensors, and detect the position of the side fence 122 in the document width direction by sensing the filler 124 attached to the guide pin of the side fence 122. Note that the number of side fence width sensors 116a to 116d is not particularly limited, and may be one or two or more.

In this embodiment, each of the side fence width sensors 116a to 116d is turned on when detecting the filler 124 of the side fence 122, and the detection results are sent to the control unit 150. The control unit 150 functions as a position acquisition unit together with the side fence width sensors 116a to 116d, and determines the position of the side fence 122 in the document width direction depending on which sensor among the four side fence width sensors 116a to 116d is turned on. Can be obtained.

FIG. 6 is a flowchart showing the raising operation of the movable table (bottom plate) 101 in this embodiment.
In this embodiment, when a user places a stack of originals P on the original table 120, the stack of originals P is detected by the original set sensor 115 (S1). As a result, when a predetermined waiting time has elapsed since the detection by the document set sensor 115 (S4), the control unit 150 rotates the bottom plate lifting motor 105 in the normal direction so that the top surface of the document bundle P on the movable table 121 is picked up. The movable table 121 is raised so that it comes into contact with the roller 141 (raised position), and prepares for an original reading instruction operation (feeding start instruction) (S5).

Here, when the user sets the document stack P on the document table 120 of the ADF 100, the document stack P is usually placed on the document table 120 (sheet placement work), and then the side fence 122 is placed on the document stack P. The side fence 122 is positioned to match the width of the document bundle P (positioning work). Therefore, a situation may occur in which the user is unable to complete the positioning work of the side fence 122 before the above-mentioned predetermined waiting time elapses.

If the movable table 121 rises to the raised position (comes into contact) before the positioning work of the side fence 122 is completed, even if you try to move the side fence 122 closer to the document stack P, the document stack P will not move. Since the document bundle P is caught between the table 121 and the pickup roller 141, the document bundle P does not move, making it impossible to complete the positioning work of the side fence 122. If document feeding is started before the positioning work of the side fences 122 is completed, the width direction position of the document is insufficiently regulated by the side fences 122, and feeding defects such as document skew are likely to occur.

Here, in the case of a small-sized document whose document width direction size is smaller than a predetermined size, a situation may occur in which the user cannot complete the positioning work of the side fence 122 before the movable table 121 reaches the raised position (abutting state). Cheap. This is considered to be due to the following reasons.

For example, small-sized originals such as postcard size are generally used less frequently than large-sized originals (for example, A4 size originals set so that the width of the original is vertical) whose original size in the width direction is larger than a specified size. . Therefore, the position of the side fence 122 immediately before a small-sized original is placed on the original table 120 is often kept at a position corresponding to a large-sized original. Therefore, when placing a small-sized original on the original table 120, it is necessary to move the side fence 122 closer to and aligning the side fence 122 with the original stack P than when placing a large-sized original on the original table 120. You will need to make a big move. Therefore, the smaller the size of the document bundle in the width direction, the more time it takes to align the side fences 122.

Moreover, the smaller the widthwise size of the document is, the more likely the document will be skewed unless the side fence 122 is positioned more accurately to regulate the widthwise position of the document bundle P. As described above, the smaller the document size in the width direction, the more accurate the positioning of the side fences 122 is required. Therefore, the smaller the size of the document bundle in the width direction, the more time it takes to align the side fences 122.

For this reason, we believe that the smaller the size of the document bundle in the width direction, the more likely it is that the user will not be able to complete the positioning work of the side fence 122 before the movable table 121 reaches the raised position (abutting state). It will be done.

Therefore, in the present embodiment, a size specifying means for specifying the width direction size of the document bundle P placed on the document table 120, and a size specifying means for specifying the width direction size of the document bundle P placed on the document table 120, and A timing changing means (control unit 150) is provided that delays the timing (switching completion timing) until the movable table 121 reaches the raised position (contact state) than when the size is larger than a predetermined size. According to this, in the case of a small-sized original, after the small-sized original is placed on the original table 120, the movable table 121 rises from the separated state to the raised position (abutting position) without waiting for an instruction to start feeding. It is possible to suppress the occurrence of a situation in which the user is unable to complete the positioning work of the side fence 122 by the time the user reaches the state).

The size specifying means in this embodiment includes side fence width sensors 116a to 116d that detect the position of the side fence 122 in the document width direction, and uses the detection results. Specifically, when the document set sensor 115 detects the document stack P placed on the document table 120 (S1), the control unit 150 controls the width of the side fence 122 based on the detection results of the side fence width sensors 116a to 116d. The document width direction position is acquired (S2). In this embodiment, the size in the width direction of the placed document bundle P is estimated (specified) from the document width direction position of the side fence 122 when the document bundle P is placed (detected by the document set sensor 115).

Specifically, when setting a stack of small-sized originals P on the document table 120, the user adjusts the position of the side fence 122 to the document table 120 prior to the sheet loading operation of placing the stack of documents P on the document table 120. It is common to perform an operation to match the approximate width of the bundle P (approximate positioning operation). Therefore, by acquiring the position of the side fence 122 in the document width direction during the period from placing the document bundle P on the document table 120 until the movable table 121 starts moving up, the It is possible to specify the size in the width direction of the document bundle P placed on the document table 120. That is, considering the above-mentioned general work contents of the user, the smaller the document width direction size corresponding to the document width direction position of the side fence 122 during the period, the smaller the document stack P placed on the document table 120. It can be estimated (specified) that the size in the width direction is small.

FIG. 7 is a graph showing an example of the relationship between the width between the two side fences 122 (the position of the side fences 122 in the document width direction) and the waiting time until the movable table (bottom plate) 121 starts rising, in this embodiment. be.
In this embodiment, in accordance with the content of the graph shown in FIG. 7, the control unit 150 determines the waiting time until the movable table (bottom plate) 121 starts rising, depending on the position of the side fence 122 in the document width direction (S3 ). According to the present embodiment, as shown in the graph shown in FIG. 7, the wait time until the movable table (bottom plate) 121 starts to rise depends on the width between the two side fences 122 (the position of the side fences 122 in the document width direction). The time changes in four stages.

Specifically, when the width between the two side fences 122 is 240 [mm] or more, the waiting time until the movable table (bottom plate) 121 starts rising is determined to be 0.5 [seconds]. Furthermore, if the width between the two side fences 122 is less than 240 [mm] (and greater than or equal to 210 [mm]), the waiting time until the movable table (bottom plate) 121 starts rising is 240 [mm]. This is determined to be 1.5 [seconds] so that the start of the rise is delayed compared to the case where the time is 1.5 [seconds] or more. Furthermore, if the width between the two side fences 122 is less than 210 [mm] (and greater than or equal to 180 [mm]), the waiting time until the movable table (bottom plate) 121 starts rising is 210 [mm]. It is determined to be 2.5 [seconds] so that the start of the rise is delayed compared to the case where it is 2.5 [seconds] or more. Furthermore, if the width between the two side fences 122 is less than 180 [mm], the waiting time for the movable table (bottom plate) 121 to start rising is delayed compared to when the width is 180 [mm] or more. Thus, it is determined to be 3.5 [seconds].

In the present embodiment, the smaller the widthwise size of the document bundle P estimated from the document widthwise position of the side fence 122, the longer the waiting time until the movable table (bottom plate) 121 starts rising. Therefore, according to the present embodiment, the smaller the size of the document bundle P in the width direction is, the later the timing (switching completion timing) until the movable table 121 reaches the raised position (contact state) becomes. Therefore, even when setting a small-sized document for which alignment of the side fences 122 is likely to take time, the user can complete the alignment of the side fences 122 before the movable table 121 reaches the raised position (abutting state). It becomes easier.

Even in the conventional configuration in which the waiting time until the movable table (bottom plate) 121 starts rising is fixed, if this waiting time is set long enough, the user can move the side fence by the time the movable table 121 reaches the raised position. This makes it easier to complete the alignment work of 122. However, in this case, the waiting time becomes long even when the user does not have time to complete the positioning work of the side fence 122, such as when processing a large-sized original. In this case, productivity is improved by completing the raising of the movable table 121 before the original reading instruction operation (feeding start instruction) is performed. The advantage of shortening the time until feeding is reduced. According to this embodiment, the user can easily complete the positioning work of the side fence 122 before the movable table 121 reaches the raised position while maintaining the advantage of improved productivity.

Note that in this embodiment, the waiting time until the movable table (bottom plate) 121 starts rising is changed in four stages depending on the width between the two side fences 122 (the position of the side fences 122 in the document width direction). The number of stages is not limited to this. For example, as shown by the broken line in FIG. 7, it may be changed in two stages (one threshold value).

Furthermore, in this embodiment, even when the document width direction size is the smallest (when the width between the two side fences 122 is less than 180 [mm]), the length of time until the movable table (bottom plate) 121 starts to rise is Although the waiting time is determined to be 3.5 seconds, it is not limited to this. That is, for example, when the document width direction size is the smallest, the movable table 121 is raised after waiting for the document reading instruction operation (feeding start instruction) to be performed on the operation unit 5 (feeding start instruction). The movable table 121 may not be raised before this is performed.

Further, in this embodiment, the position of the side fence 122 in the document width direction is detected discontinuously (in 4 steps) using the four side fence width sensors 116a to 116d. The configuration for detecting the position is not particularly limited. For example, a configuration using a variable resistor whose electrical resistance value changes depending on the position of the side fence 122 in the document width direction may be adopted. In the case of this configuration, it is possible to detect the position of the side fence 122 in the document width direction in more detail than in the configuration of this embodiment, and the configuration can also be realized easily. In the case of a configuration in which the position of the side fence 122 in the document width direction is continuously detected, for example, according to the contents of the graph shown in FIG. may be changed.

Furthermore, in the present embodiment, as a method for specifying the size in the width direction of the document bundle P placed on the document table 120, a method of estimating (identifying) from the position of the side fence 122 in the document width direction is adopted. , but not limited to this. For example, the user inputs the size in the width direction of the document bundle P by operating the operation unit 5 on which the operation screen shown in FIG. A method of specifying the size in the width direction of the document bundle P placed on the paper 120 may also be used. In the example shown in FIG. 9, the user selects the numerical value of the document width displayed on the operation screen as appropriate, and operates "Execute paper feeding/ejection processing" on the operation screen to perform the document reading instruction operation (instruction to start feeding). ) is done. Note that instead of operating the operation screen, the user may input the widthwise size of the document bundle P by mechanically operating a switch.

Further, as a method of specifying the width direction size of the document bundle P placed on the document table 120, for example, a sensor device such as a plurality of optical sensors for detecting the presence or absence of the document bundle P on the document table 120 is The width direction size of the document stack P on the document table 120 is detected directly based on the detection results of these sensor devices. It may be something that does. However, before the document stack P on the document table 120 is regulated by the side fence 122, the edges in the document width direction may be uneven, or the placement position on the document table 120 may be deviated from the reference position. This is often the case. It should be noted that with a configuration that directly detects the widthwise size of the document stack P in such a state, it is difficult to accurately detect the widthwise size of the document stack P, and there is a risk of false detection. Should.

[Modification 1]
Next, a modified example of the raising operation of the movable table 121 in this embodiment (hereinafter, this modified example will be referred to as "modified example 1") will be described.
In the embodiment described above, as a method of delaying the timing (switching completion timing) until the movable table 121 reaches the raised position (contact state), the waiting time until the movable table (bottom plate) 121 starts rising is lengthened. method is adopted. In this modification example 1, as shown in the graph shown in FIG. 10, as a method of delaying the timing (switching completion timing) until the movable table 121 reaches the raised position (contact state), the movable table (bottom plate) 121 is raised. Adopt a method of slowing down the speed.

According to this first modification, even if the waiting time until the movable table (bottom plate) 121 starts rising is fixed, the timing (switching completion timing) until the movable table 121 reaches the rising position (contact state) is fixed. It can be delayed. Note that in the case of a configuration in which the position of the side fence 122 in the document width direction is continuously detected, a graph such as that shown in FIG. 11 may be used, for example.

FIG. 12 is a flowchart showing the raising operation of the movable table (bottom plate) 101 in the first modification.
In the first modification, the control unit 150 determines the rising speed of the movable table (bottom plate) 121 according to the position of the side fence 122 in the document width direction (S3'). Then, when a predetermined waiting time (fixed) has elapsed since the detection by the document set sensor 115 (S4), the control unit 150 rotates the bottom plate lifting motor 105 in the normal direction at a rotation speed corresponding to the determined lifting speed, and The movable table 121 is raised so that the uppermost surface of the document bundle P on the document stack P comes into contact with the pickup roller 141 (raised position) (S5').

In the first modification, the smaller the size of the document bundle P in the width direction estimated from the position of the side fence 122 in the document width direction becomes, the slower the rising speed of the movable table (bottom plate) 121 becomes. Therefore, also in the present modification 1, the smaller the size of the document bundle P in the width direction, the later the timing (switching completion timing) until the movable table 121 reaches the raised position (contact state). Therefore, even when setting a small-sized document for which alignment of the side fences 122 is likely to take time, the user can complete the alignment of the side fences 122 before the movable table 121 reaches the raised position (abutting state). It becomes easier.

[Modification 2]
Next, another modification of the raising operation of the movable table 121 in this embodiment (hereinafter, this modification will be referred to as "Modification 2") will be described.
In the embodiment described above, when the detected width (width direction position) of the side fence 122 is narrow (when the width direction size of the document bundle P is smaller than a predetermined size), the movable table 121 is moved to the raised position (in the contact state). ) (switching completion timing) is delayed. In this modification 2, the error between the detected width (width direction position) of the side fence 122 and the width direction size of the document bundle P (width direction position of the side fence 122 corresponding to the width direction size of the document bundle P) is larger than a predetermined error, the timing (switching completion timing) until the movable table 121 reaches the raised position (contact state) is delayed.

In the second modification, a position acquisition means for acquiring the width (widthwise position) of the side fence 122 and a size specifying means for determining the widthwise size of the document bundle P placed on the document table 120 are required. . As in the above-described embodiment, the position acquisition means uses the results of the four side fence width sensors 116a to 116d detecting the filler 124 attached to the guide pin of the side fence 122, and the control unit 150 determines the position of the side fence 122. Get the document width direction position.

The size specifying means of the present modification 2 needs to use a means different from the position acquiring means. Therefore, in the second modification, the user inputs the widthwise size of the document bundle P by, for example, operating the operation unit 5 on which the operation screen as shown in FIG. A size specifying means for specifying the size in the width direction of the document bundle P placed on the document table 120 from the result is employed.

FIG. 13 is a flowchart showing the raising operation of the movable table (bottom plate) 101 in the second modification.
Before or after the user places the document stack P on the document table 120, the control section 150 causes the operation section 5 to display an operation screen as shown in FIG. 9 (S11). In response to this, when the user inputs the width direction size of the document stack P placed on the document table 120 into the operation unit 5, the control unit 150 determines the size of the document stack P placed on the document table 120 based on the input result. The width direction size is specified (S12).

On the other hand, when the user places the document stack P on the document table 120, the document set sensor 115 detects the document stack P (S13). When the document set sensor 115 detects the document bundle P, the control unit 150 acquires the document width direction position of the side fence 122 from the detection results of the side fence width sensors 116a to 116d (S14).

Thereafter, the control unit 150 determines the width direction size of the specified document bundle P (the width direction position of the side fence 122 corresponding to the specified width direction size of the document bundle P) and the acquired document width direction position of the side fence 122. The waiting time until the movable table (bottom plate) 121 starts rising is determined according to the error (S15). For example, it is changed stepwise or continuously so that the larger this error is, the longer the waiting time until the movable table (bottom plate) 121 starts rising.

Then, when the determined waiting time has elapsed since the detection by the document set sensor 115 (S16), the control unit 150 rotates the bottom plate lifting motor 105 in the normal direction so that the top surface of the document bundle P on the movable table 121 is picked up. The movable table 121 is raised so that it comes into contact with the roller 141 (raised position) (S17).

In the second modification, the specified width direction size of the document bundle P (width direction position of the side fence 122 corresponding to the width direction size of the specified document bundle P) and the acquired document width direction position of the side fence 122. The larger the error, the slower the timing (switching completion timing) until the movable table 121 reaches the raised position (contact state). The larger this error is, the more time it takes to align the side fence 122 because it is necessary to move the side fence 122 more in order to bring the side fence 122 closer to the document bundle P for alignment. Therefore, according to the second modification, even if this error is large and it takes time to align the side fence 122, the user can move the side fence 122 by the time the movable table 121 reaches the raised position (abutting state). This makes it easier to complete the alignment task.

Note that in the present embodiment (including modified examples), an example has been described in which the original (sheet) to be read by the image reading unit included in the ADF 100 is set on the original table 120. Not limited to. For example, the present invention can be similarly applied to the case where a recording paper (sheet) on which an image is formed by the image forming section 3 is set in a feed tray such as a manual feed tray. Specifically, the present invention is applicable to the feeding cassettes 21 and 22 provided in the feeding section 2 of the copying machine 1 and the manual feed tray of the copying machine 1.

What has been described above is just an example, and each of the following aspects has its own unique effects. [First aspect]
The first aspect includes a placing section (for example, the document table 120) on which a sheet bundle (for example, the document stack P) is placed, and a feeding member (for example, the document table 120) that abuts and feeds the sheets placed on the sheet placing section. For example, a sheet feeding device including a pickup roller 141) and a regulating section (for example, a side fence 122) configured to be movable in the sheet width direction and regulating the position of the sheet bundle on the sheet placement section in the sheet width direction. (for example, the document setting section A of the ADF 100), after the sheet stack is placed on the loading section, the sheet stack on the loading section and the feeding member are connected without waiting for a feeding start instruction. from a separated state in which the sheets are separated from each other (for example, a state in which the movable table 121 is in the lowered position) to a contact state in which the sheet bundle on the loading section and the feeding member are in contact (for example, in a state in which the movable table 121 is in the raised position). ) (for example, the bottom plate lift motor 105), and a size specifying means (for example, the side fence width sensors 116a to 116d, the operation unit 5 ), and a timing change means that delays the timing of completion of switching from the separated state to the contact state when the sheet width direction size specified by the size specifying means is smaller than a predetermined size than when the sheet width direction size is larger than the predetermined size. (for example, the control unit 150).
Generally, the user places a sheet stack on the stacking section (sheet loading work), and then moves the regulating section close to the sheet stack and positions the regulating section to match the width of the sheet stack (regulating section positioning task). )I do. Conventionally, without waiting for a feeding start instruction, the sheet stack on the stacking section and the feeding member are separated from each other, to the contact state where the sheet stack on the stacking section and the feeding member are in contact with each other. In the configuration in which the control part is switched to , a situation may occur in which the contact state is reached before the positioning work of the restriction part is completed. If the regulating section comes into contact before the alignment work is completed, the sheet stack will be caught between the stacking section and the feeding member even if you try to move the regulating section close to the sheet stack. Since the sheet bundle does not move, it becomes impossible to complete the positioning work of the regulating section. If sheet feeding is started before the alignment work of the regulating section is completed, sheet feeding defects such as sheet skew are likely to occur because the regulating section does not sufficiently regulate the position of the sheet in the width direction.
The present inventor discovered that in the case of a sheet whose size in the sheet width direction is small (a sheet smaller than a predetermined size), it is likely that the user will not be able to complete the positioning work of the regulating portion before the contact state is reached. I found out. This is considered to be due to the following reasons.
A small size sheet (for example, postcard size) whose sheet width direction size is smaller than a predetermined size is generally used less frequently than a large sheet (for example, A4 size) whose sheet width direction size is a predetermined size or more. Therefore, the position of the regulating section immediately before placing the small-sized sheet on the placing section often remains at the position corresponding to the large sheet. Therefore, when placing a small size sheet on the stacking section, in order to bring the regulating section closer to the sheet stack and positioning it, it is necessary to move the regulating section more than when placing a large sheet on the stacking section. come out. Moreover, the smaller the size of the sheet in the width direction, the more likely sheet skew will occur unless the regulating portion is positioned more accurately to regulate the position of the sheet bundle in the width direction. As described above, the smaller the size of the sheet in the width direction, the more accurate the positioning of the restricting portion is required, and therefore the work of positioning the restricting portion for a small-sized sheet tends to take a long time. For these reasons, in the case of small-sized sheets, it is thought that a situation where the user is unable to complete the positioning work of the regulating portion before the contact state is reached is likely to occur.
Therefore, in this aspect, when the sheet width direction size specified by the size specifying means is smaller than a predetermined size, the timing change means completes the switching from the separation state to the contact state than when the sheet width direction size specified by the size specifying means is equal to or larger than the predetermined size. delay timing. According to this, in the case of a small size sheet, it is possible to suppress the occurrence of a situation in which the user is unable to complete the positioning work of the regulating portion before the contact state is reached.

[Second aspect]
In a second aspect, in the first aspect, the position acquisition means (for example, side fence width sensors 116a to 116d) acquires the position of the regulating portion in the sheet width direction, and the size specifying means acquires the position of the regulating portion in the sheet width direction. The present invention is characterized in that the sheet width direction size of the sheet bundle to be placed on the loading section is specified based on the results.
When placing a stack of small-sized sheets on the stacking section, the user must adjust the position of the regulating section on the stack of sheets before placing the stack of sheets on the stacking section (sheet loading operation). It is common to perform work to roughly match the width (rough positioning work). Therefore, by acquiring the position of the regulating section in the sheet width direction by the position acquisition means, it is possible to specify the sheet width direction size of the sheet bundle to be placed on the placing section before the switching starts. In other words, considering the general work content of the user described above, the smaller the sheet width direction size corresponding to the sheet width direction position of the regulating section during the period, the sheet width of the sheet bundle placed on the stacking section. It can be estimated (specified) that the directional size is small.

[Third aspect]
In a third aspect, based on the second aspect, the position acquisition means acquires the sheet width direction position of the regulating section in a period from when the sheet bundle is placed on the loading section until when the switching is started. It is characterized by this.
According to this, the position acquisition means acquires the position of the regulating section in the sheet width direction during the period from when the sheet bundle is placed on the loading section until the switching from the separation state to the contact state starts. Therefore, it is possible to specify the sheet width direction size of the sheet bundle to be placed on the loading section before starting the switching.

[Fourth aspect]
A fourth aspect includes a placing section (for example, document table 120) on which a sheet bundle (for example, document stack P) is placed, and a feeding member (for example, document table 120) that abuts and feeds the sheets placed on the sheet placing section. For example, a sheet feeding device including a pickup roller 141) and a regulating section (for example, a side fence 122) configured to be movable in the sheet width direction and regulating the position of the sheet bundle on the sheet placement section in the sheet width direction. (for example, the document setting section A of the ADF 100), after the sheet stack is placed on the loading section, the sheet stack on the loading section and the feeding member are connected without waiting for a feeding start instruction. from a separated state in which the sheets are separated from each other (for example, a state in which the movable table 121 is in the lowered position) to a contact state in which the sheet bundle on the loading section and the feeding member are in contact (for example, in a state in which the movable table 121 is in the raised position). ), a size specifying means (for example, the operation section 5) for specifying the size in the sheet width direction of the sheet bundle placed on the sheet placement section, and a size specifying section (for example, the operation section 5) for specifying the sheet width direction size of the sheet bundle placed on the sheet placement section; A position acquisition means (for example, side fence width sensors 116a to 116d) that acquires the width direction position, a sheet width direction position of the regulating portion corresponding to the sheet width direction size specified by the size specifying means, and the position acquisition means When the error with the acquired sheet width direction position is larger than a predetermined error, timing changing means (for example, the control unit 150 ).
The farther the position of the regulating section in the sheet width direction is out of line with the widthwise size of the sheet stack placed on the stacking section, the more the regulating section must be moved to bring the regulating section closer to the sheet stack for alignment. Therefore, it is easy to take time to align the regulating part.
In this aspect, the timing change means causes the error between the sheet width direction position of the regulating portion corresponding to the sheet width direction size specified by the size specifying means and the sheet width direction position acquired by the position acquisition means to be larger than a predetermined error. When the error is larger than the predetermined error, the timing of completing switching from the separation state to the contact state is delayed compared to when the error is less than or equal to the predetermined error. According to this, when the position of the regulating section in the sheet width direction is significantly different from the widthwise size of the sheet bundle placed on the stacking section, the user must press the regulating section before the contact state is reached. It is possible to suppress the occurrence of a situation in which the alignment work cannot be completed.

[Fifth aspect]
A fifth aspect is size specifying information (for example, an input result to the operation unit 5) for specifying the size in the sheet width direction of the sheet bundle to be placed on the loading section in any of the first to fourth aspects. The size specifying means is configured to determine the sheet width of the sheet bundle to be placed on the stacking section based on the size specifying information obtained by the information obtaining section. This method is characterized by specifying the directional size.
According to this, the size in the sheet width direction of the sheet bundle placed on the stacking section can be specified using the existing information acquisition means installed in the sheet feeding device, so the size specifying means There is no need to separately provide (sensor equipment, etc.), and the configuration can be simplified.

[Sixth aspect]
A sixth aspect is that in any one of the first to fifth aspects, the timing changing means continuously changes the switching completion timing within a predetermined sheet width direction size range. .
According to this, it is possible to implement more detailed control to delay the switching completion timing.

[Seventh aspect]
In a seventh aspect, in any one of the first to fifth aspects, the timing changing means changes the switching completion timing in stages within a predetermined sheet width direction size range. .
According to this, control to delay the switching completion timing can be easily implemented.

[Eighth aspect]
In an eighth aspect, in any one of the first to seventh aspects, the timing changing means changes the switching completion timing by changing the switching start timing from the separation state to the contact state. This is a characteristic feature.
According to this, even if the switching speed from the separated state to the contact state remains fixed, the switching completion timing can be delayed.

[Ninth aspect]
A ninth aspect is that in any one of the first to eighth aspects, the timing changing means changes the switching completion timing by changing the switching speed from the separation state to the contact state. That is.
According to this, even if the start timing of switching from the separated state to the contact state remains fixed, the switching completion timing can be delayed.

[Tenth aspect]
In a tenth aspect, in any one of the first to ninth aspects, there is provided a detection means (for example, a document set sensor 115) for detecting that a sheet bundle is placed on the placement section, and the size identification means is The present invention is characterized in that the size in the sheet width direction of the sheet bundle placed on the loading section is specified when the sensing means detects the sheet.
According to this, the sheet width direction size of the sheet bundle to be placed on the placing section can be specified at an early stage.
[Eleventh aspect]
An eleventh aspect is the one according to any one of the first to tenth aspects, wherein the feeding member feeds the uppermost sheet of the sheet bundle placed on the loading section by contacting the uppermost sheet. It is.
According to this, in a sheet feeding device that feeds the uppermost sheet of a stack of sheets placed on a stacking unit, before the sheet stack on the stacking unit and the feeding member come into contact with each other. In addition, it is possible to suppress the occurrence of a situation in which the positioning of the regulating section to match the width of the sheet bundle (positioning work of the regulating section) cannot be completed.

[Twelfth aspect]
A twelfth aspect is an automatic sheet feeding device (for example, ADF 100), which includes the sheet feeding device of any one of the first to eleventh aspects.
According to this, in an automatic sheet feeding device, the positioning of the regulating section to match the width of the sheet stack (positioning of the regulating section) is performed before the sheet stack on the loading section comes into contact with the feeding member. It is possible to suppress the occurrence of a situation in which a task cannot be completed.

[13th aspect]
A thirteenth aspect is an image reading device (for example, an ADF 100), which includes the sheet feeding device of any one of the first to eleventh aspects.
According to this, in an image reading device, the positioning of the regulating section to match the width of the sheet stack (positioning of the regulating section) is performed before the sheet stack on the loading section and the feeding member come into contact with each other. ) can be prevented from occurring.

[14th aspect]
A fourteenth aspect is an image forming apparatus (for example, a copying machine 1), which includes the sheet feeding device according to any one of the first to eleventh aspects.
According to this, in an image forming apparatus, before the sheet stack on the stacking section and the feeding member come into contact, the regulating section is positioned to match the width of the sheet stack (positioning of the regulating section is performed). ) can be prevented from occurring.

1: Copying machine 2: Feeding section 3: Image forming section 4: Contact glass 5: Operation section 6: Main body control section 31: Exposure device 32: Photosensitive drum 33: Developing device 34: Transfer belt 35: Fixing device 100: ADF
101: Pick-up motor 102: Feed motor 103: Reading motor 104: Paper ejection motor 105: Bottom plate lift motor 111: Abutment sensor 112: Reading entrance sensor 113: Registration sensor 114: Paper ejection sensor 115: Original set sensor 116a to 116d : Side fence width sensor 117 : Bottom plate home position sensor 118 : Table rise sensor 120 : Original table 121 : Movable table 121a : Rotation shaft 122 : Side fence 123 : Guide groove 124 : Filler 131 : First image reading section 132 : First Two image reading sections 141: Pick-up roller 142: Separation roller pair 142A: Feeding roller 142B: Reverse roller 143: Pull-out roller pair 144: Intermediate roller 145: Reading entrance roller pair 146: First reading exit roller 147: Second reading exit Roller 148: Paper discharge roller pair 150: Control section A: Document setting section B: Separation and feeding section C: Registration section D: Turn section E: First reading and conveying section F: Second reading and conveying section G: Paper discharge section H : Stack section P : Document bundle

Japanese Patent Application Publication No. 2004-238160

Claims (14)

a loading section on which a sheet bundle is placed;
a feeding member that comes into contact with and feeds the sheet placed on the loading section;
A sheet feeding device comprising: a regulating section configured to be movable in the sheet width direction and regulating the position of the sheet bundle on the sheet placement section in the sheet width direction,
After the sheet stack is placed on the loading section, without waiting for a feeding start instruction, the sheet stack on the loading section is changed from the separated state in which the sheet stack on the loading section and the feeding member are separated. a switching means for switching to a contact state in which the sheet bundle and the feeding member are in contact with each other;
size specifying means for specifying the sheet width direction size of the sheet bundle placed on the loading section;
When the sheet width direction size specified by the size specifying means is smaller than a predetermined size, timing changing means delays the timing of completion of switching from the separated state to the contact state than when the sheet width direction size is smaller than the predetermined size. A sheet feeding device comprising: The sheet feeding device according to claim 1,
comprising a position acquisition means for acquiring the position of the regulating portion in the sheet width direction;
The sheet feeding apparatus is characterized in that the size specifying means specifies a sheet width direction size of the sheet bundle to be placed on the placement section based on the acquisition result of the position acquisition section. The sheet feeding device according to claim 2,
The sheet feeding device is characterized in that the position acquisition means acquires the sheet width direction position of the regulating section during a period from when the sheet bundle is placed on the loading section until when the switching is started. a loading section on which a sheet bundle is placed;
a feeding member that comes into contact with and feeds the sheet placed on the loading section;
A sheet feeding device comprising: a regulating section configured to be movable in the sheet width direction and regulating the position of the sheet bundle on the sheet placement section in the sheet width direction,
After the sheet stack is placed on the loading section, without waiting for a feeding start instruction, the sheet stack on the loading section is changed from the separated state in which the sheet stack on the loading section and the feeding member are separated. a switching means for switching to a contact state in which the sheet bundle and the feeding member are in contact with each other;
size specifying means for specifying the sheet width direction size of the sheet bundle placed on the loading section;
a position acquisition means for acquiring the position of the regulating portion in the sheet width direction;
When the error between the sheet width direction position of the regulating portion corresponding to the sheet width direction size specified by the size specifying means and the sheet width direction position acquired by the position acquisition means is larger than a predetermined error, the error is less than or equal to the predetermined error. A sheet feeding device comprising: timing changing means for delaying the timing at which switching from the separated state to the contact state is completed than when the sheet feeding device is in the contact state. The sheet feeding device according to any one of claims 1 to 4,
comprising information acquisition means for acquiring size specifying information for specifying the sheet width direction size of the sheet bundle placed on the loading section;
The sheet feeding device is characterized in that the size specifying unit specifies a size in the sheet width direction of the sheet bundle placed on the loading section based on the size specifying information acquired by the information acquiring unit. The sheet feeding device according to any one of claims 1 to 4,
The sheet feeding apparatus is characterized in that the timing changing means continuously changes the switching completion timing within a predetermined sheet width direction size range. The sheet feeding device according to any one of claims 1 to 4,
The sheet feeding device is characterized in that the timing changing means changes the switching completion timing stepwise within a predetermined sheet width direction size range. The sheet feeding device according to any one of claims 1 to 4,
The sheet feeding apparatus is characterized in that the timing changing means changes the switching completion timing by changing the switching start timing from the separated state to the contact state. The sheet feeding device according to any one of claims 1 to 4,
The sheet feeding apparatus is characterized in that the timing changing means changes the switching completion timing by changing the switching speed from the separation state to the contact state. The sheet feeding device according to any one of claims 1 to 4,
comprising a detection means for detecting that a sheet bundle is placed on the loading section,
The sheet feeding apparatus is characterized in that the size specifying means specifies the sheet width direction size of the sheet bundle placed on the placement section when the detection means detects the size. The sheet feeding device according to any one of claims 1 to 4,
The sheet feeding device is characterized in that the feeding member feeds the uppermost sheet of the sheet bundle placed on the loading portion by contacting the top sheet. An automatic sheet feeding device comprising the sheet feeding device according to any one of claims 1 to 4. An image reading device comprising the sheet feeding device according to any one of claims 1 to 4. An image forming apparatus comprising the sheet feeding device according to any one of claims 1 to 4.

Images