JP5301954B2 - Sheet feeding apparatus and image reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the alignment property of sheets discharged from a sheet feeder by suppressing disturbance in the discharge attributable to abnormal shape of the sheets fed into the sheet feeder. <P>SOLUTION: A sheet feeder comprises a paper feed unit A1 for feeding sheets in an image reader 100, a discharge unit A2 for discharging the sheets from the image reader 100, a light emission/reception unit 4 for detecting any abnormality of the shape of the sheets to be fed in the image reader 100 by the paper feed unit A1, a speed control unit 21 for controlling the sheet discharging speed based on the result of detection of abnormality in the shape by the light emission/reception unit 4. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

The present invention relates to a sheet feeding apparatus and an image reading apparatus that feed sheets.

  2. Description of the Related Art Image forming apparatuses such as copiers and printers and image reading apparatuses such as scanners are provided with a sheet feeding apparatus having a function of discharging sheets from the apparatus main body and stacking them on a paper discharge tray. As this sheet feeding device, for example, the following technique is disclosed.

  FIG. 9 is a diagram illustrating a schematic configuration of a paper discharge tray according to Patent Document 1. In FIG. The mounting height of the discharge tray B1 can be manually changed. Contrary to the sheet of FIG. 9, when discharging a sheet whose front end and rear end in the discharge direction are bent and bent downward (mountain folded state), the discharge tray B1 is shifted upward to discharge the sheet. It can be carried out. This is because when the sheet is folded in a mountain state, it hangs down from the paper discharge port, and is rounded in contact with the paper discharge tray at a position close to the paper discharge port, so the position of the paper discharge tray B1 is displaced upward. This is so that the seat is landed before it hangs down. As a result, even when the sheet is in a mountain folded state, the sheet alignment is improved by adjusting the height of the sheet discharge tray.

  FIG. 10 is a diagram illustrating a discharge speed control procedure according to Patent Document 2. Patent Document 2 discloses a technique for detecting the size of a fed sheet and controlling the discharge speed based on the size of the sheet. For example, when a relatively large size sheet is ejected vigorously, it may fall from the sheet ejection tray, and therefore the ejection speed is controlled according to the detected sheet size.

Moreover, FIG. 11 is a figure which shows the control procedure of the discharge speed which concerns on patent document 3. FIG. In Patent Document 3, the thickness of the sheet is detected based on the transparency of the fed sheet, and the discharge speed is controlled based on the detection result. By discharging the sheet at a relatively low thickness when discharging a relatively thin sheet, the sheet is prevented from falling from the sheet discharge tray and misalignment is prevented.
JP 2003-128323 A JP-A-5-43121 Japanese Patent Laid-Open No. 2-95663

  However, the paper discharge tray disclosed in Patent Document 1 can be adjusted to improve the alignment by adjusting the height of the paper discharge tray when feeding a folded sheet. When not only the sheet in the mountain folded state but also the sheet in which the front end and the rear end in the feeding direction are curved and bent upward (valley folded state) are mixedly loaded, the user can respond to the state of the sheet. Therefore, it is necessary to adjust the height of the discharge tray at any time, which is troublesome.

  Further, in Patent Documents 2 and 3, the sheet size or thickness is detected, and the sheet discharge speed is changed based on the detection result, and the discharge speed is not changed with respect to the bending / bending of the sheet. For this reason, when feeding a curved or bent sheet, if the discharged sheet is bent in a mountain-folded state, the leading edge of the sheet will land on the output tray quickly due to air resistance, and the sheet will be curled up. May occur, leading to poor alignment and out of order.

Accordingly, an object of the present invention, by suppressing the turbulence at the time of discharge due to the shape of the sheet has been fed into the apparatus, is to improve the alignment of the sheet discharged from the apparatus.

In order to solve the above problems, a sheet feeding apparatus according to the present invention includes a sheet stacking unit on which sheets are stacked, a sheet feeding unit that feeds sheets into the apparatus, and a discharging unit that discharges the sheets from the apparatus. If, until incorporated into the paper feeding means in said apparatus is started feeding into the apparatus, a detecting means for detecting the shape change of the sheet you move on the sheet stacking portion, the detection The result of the detection using the detection means when discharging the sheet, which has detected a change in the shape of the sheet from when the sheet is fed into the apparatus to the inside of the apparatus during sheet feeding using the means, And a speed control means for controlling the discharge speed of the sheet discharged to the outside of the apparatus .

According to the present invention, by suppressing the turbulence at the time of discharge due to the shape of the sheet has been fed into the apparatus, it is possible to improve the alignment of the sheet discharged from the apparatus.

  Embodiments of the present invention will be described below in detail with reference to the drawings. The embodiment described below is an example as means for realizing the present invention, and the present invention can be applied to a modified or modified embodiment described below without departing from the spirit of the present invention.

<First Embodiment>
FIG. 1 is a side sectional view schematically showing an image reading apparatus 100 according to the first embodiment of the present invention. FIG. 2 is a block diagram illustrating a functional configuration of the image reading apparatus 100. FIG. 4 is a diagram illustrating a configuration of the light emitting / receiving unit 4.

  The image reading apparatus 100 is integrally provided with a sheet feeding device, and includes an upper unit 1 and a lower unit 2 that supports the upper unit 1. Since the image reading apparatus 100 ejects the sheet by making a U-turn, the front and back of the sheet are reversed with respect to the time of sheet feeding. The substantially horizontal sheet feeding tray 3 (stacking unit) is attached facing the sheet feeding port, and can stack a plurality of fed sheets. Further, the height of the paper feed tray 3 can be automatically adjusted according to the load amount.

  The light emitting / receiving unit 4 is an example of a detecting unit that emits and receives light in order to detect that the shape of the sheet fed into the image reading apparatus 100 is an abnormal shape. The light emitting / receiving unit 4 includes a light receiving unit 4a having a plurality of light receiving elements arranged in the vertical direction and a light emitting unit 4b having a plurality of light emitting elements arranged in the vertical direction. As shown in FIG. 4, the light emitting unit 4b is disposed to face the light receiving unit 4a with the sheet D1 stacked on the paper feed tray 3 interposed therebetween. The light emitting / receiving unit 4 is disposed on the upstream side in the sheet feeding direction from a pickup roller 5 described later. The light receiving / emitting unit 4 receives a signal that changes in response to a change in the light receiving state at the light receiving unit 4a (that is, a change in the light blocking position) by the curved portion of the sheet blocking the light emitted from the light emitting unit 4b. By outputting, the CPU 20 described later can detect the direction and amount of bending / bending. It is possible to detect the distance from the reference height substantially continuously by a signal from the light emitting / receiving unit 4, and it will be described later that the shape of the sheet is an abnormal shape when the detected distance is larger than the threshold value. CPU 20 detects. The light emitting / receiving unit 4 is preferably disposed substantially perpendicular to the paper feed tray 3.

  The pickup roller 5 is movable in the vertical direction, abuts on the sheets stacked on the sheet feeding tray 3 from above, and feeds the sheets into the image reading apparatus 100. That is, the pickup roller 5 is driven by a paper feed motor 6 and is provided so as to be able to be separated from and attached to the sheets stacked on the paper feed tray 3. When the sheets are fed, the pickup roller 5 is lowered and stacked on the paper feed tray 3. Abutted against the sheet. When the sheet is fed until it comes into contact with the feeding roller 7, the pickup roller 5 moves away from the sheet stacked on the sheet feeding tray 3 (that is, rises) and waits until the next sheet is fed.

  The feeding roller 7 is disposed on the downstream side of the pickup roller 5 and feeds the sheet fed by the pickup roller 5 into the image reading apparatus 100. The separation roller 8 can rotate in the reverse direction with respect to the feeding direction. When a plurality of sheets are fed by the pickup roller 5, the separation roller 8 rotates in the reverse direction with respect to the feeding direction to rotate the sheet 1. It can be separated one by one. The transport rollers 9, 10, 11, and 12 are driven by the main motor 13 and rotate at the same speed.

  In the vicinity of the downstream side of the feeding roller, a sheet size detection sensor 14 capable of measuring the sheet passing time in order to detect the sheet size is provided. Further, the image reading apparatus 100 includes a CPU 20 that controls sheet feeding processing. Further, the CPU 20 pays attention to the speed control unit 21 that controls the discharge speed of the sheet based on the detection result of the abnormal shape of the sheet by the signal output from the light emitting and receiving unit 4 and the discharge speed of the target sheet. It also functions as a timing control unit 22 (paper feed control means) that controls the paper feed timing of a sheet fed next to the sheet to be fed.

  When the conveyed sheet passes through the sheet detection sensor 15, the CPU 20 starts reading an image by the image reading unit 16 by measuring the reading timing from the detection signal output from the sheet detection sensor 15 when the sheet passes.

  The paper discharge roller 18 is disposed on the downstream side of the image reading unit 16 and is driven by a paper discharge motor 19. The sheet detection sensor 17 monitors whether or not the sheet has passed and detects the trailing edge of the sheet. Based on this signal, the CPU 20 issues a command to change the rotation speed of the paper discharge roller 18. When the sheet is detected by the sheet detection sensor 17, the CPU 20 discharges the paper discharge motor 19 at a normal speed, a speed decelerated from the normal speed, or a speed accelerated from the normal speed. Further, as shown in FIG. 2, the CPU 20 receives signals from the sensors and controls the speeds of the motors.

  FIG. 3 is a diagram illustrating a control procedure of the CPU 20. 7A is a diagram showing an example of performing sheet detection processing on a sheet with little deformation using the light emitting / receiving unit 4, and FIG. 7B shows a detection result based on a signal from the light emitting / receiving unit 4. FIG. 8A is a diagram illustrating an example in which sheet detection processing is performed on a highly deformed sheet using the light emitting / receiving unit 4, and FIG. 8B illustrates a detection result based on a signal from the light emitting / receiving unit 4. FIG.

  First, in step S1, when the CPU 20 receives a conveyance start instruction, in step S2, the sheet feeding tray 3 is raised until the sheet placed on the sheet feeding tray 3 reaches a position where the sheet is fed, and the pickup roller Is brought into contact with the sheet to start feeding the sheet.

  When the sheet feeding is started, in step S3, the light receiving and emitting unit 4 detects the vertical position (hereinafter referred to as a light shielding position) where the light emitted from the light emitting element is blocked by the sheet D1 at predetermined time intervals. . Since the light emitting / receiving unit 4 has a plurality of light emitting / receiving elements, a plurality of light shielding positions can be detected. In addition, it is possible to detect the height of the light shielding position substantially continuously by performing multi-value detection of the amount of light received by the light receiving element. As a result, the light emitting / receiving unit 4 detects the direction and amount of bending / bending of the sheet D1.

  Next, in step S4, the image is read by the image reading unit 16, and in step S5, the sheet size is detected at the timing when the leading edge and the trailing edge of the sheet pass through the sheet size detection sensor 14.

  Thereafter, in step S6, the CPU 20 determines whether or not the sheet is bent or bent based on the light shielding positions detected at predetermined time intervals in step S3.

  For example, when the sheet D2 as shown in FIG. 7A is fed into the image reading apparatus 100, the detection result based on the signal from the light emitting / receiving unit 4 is as shown in FIG. 7B. . That is, the sheet D2 has almost no fluctuation in the light shielding position, that is, since the fluctuation is smaller than a predetermined amount, it is determined that there is no bending / bending. On the other hand, as shown in FIG. 8A, when there is a sheet D3 having a large bend on the sheet feed tray 3, the detection result based on the signal from the light emitting and receiving unit 4 is as shown in FIG. Thus, it is determined that there is a curve or a bend. As described above, the CPU 20 determines that there is no bending / bending when the sheet shown in FIG. 7A passes, and there is a bending / bending when the sheet shown in FIG. 8A passes. Is determined.

  If it is determined in step S6 that there is no bending / bending, the process proceeds to step S12. On the other hand, if it is determined in step S6 that there is a curve / bend, the length of the sheet is determined in step S7 based on the sheet size detected in step 5 described above.

  Thereafter, in step S8, it is determined based on the detection result of the light shielding position whether or not the bending / bending is a mountain fold state. If it is determined in step S8 that the curve / bend is a mountain fold state, in step S9, the discharge rate is set to a value larger than the normal discharge rate as the amount of the curve / bend increases. On the other hand, if it is determined in step S8 that the bending / bending is not in the mountain folded state (that is, in the valley folded state), in step S10, the timing of feeding the next sheet is set late, and step S11 is performed. In this case, the discharge rate is set to a value smaller than the normal discharge rate as the amount of bending / bending increases. That is, the CPU 20 changes the speed of the paper discharge motor based on the direction and amount of bending / bending determined from the detection result of the light emitting / receiving unit 4.

  Here, the CPU 20 performs control to set the discharge speed to a value smaller than the normal discharge speed when the direction of bending / bending is a valley fold state. May collide with the trailing edge of the previously ejected paper. Therefore, in this embodiment, in step S10, the raising and lowering of the pickup roller 5 is controlled, and the control for delaying the paper feed timing is performed.

  Thereafter, in step S12, a signal to feed the next sheet is transmitted. Finally, in step S13, the sheet is ejected from the image reading apparatus 100, and a series of processing ends.

  The operation when a sheet having a normal size (for example, A4 sheet) without bending is fed and conveyed by the above processing is as follows. The image reading apparatus 100 illustrated in FIG. 1 has a plurality of sheets stacked on the sheet feeding tray 3.

  When receiving an image reading instruction from a host computer or the like, the CPU 20 drives the paper feed motor 6 to feed the sheet. When a sheet is fed, the sheet size detection sensor 14 reads the sheet size. Thereafter, the sheet detection sensor 15 detects that the leading edge of the sheet has passed, and transmits the information to the CPU 20.

  The CPU 20 reads an image by the image reading unit 16 based on the information that the sheet has passed. Then, the sheet is conveyed to a discharge port and discharged at a discharge speed suitable for a normal size (for example, A4 paper). The discharge speed suitable for this normal sheet size is the normal discharge speed. When the discharge speed is not changed according to the sheet size, the detection of the sheet size and the determination of the sheet length (steps S5 and S7) are omitted, and the normal discharge speed may be a fixed value.

  Hereinafter, an operation when a sheet having a normal size (for example, A4 paper) having an abnormal shape due to bending or bending is fed and conveyed will be described with reference to FIG. 5A is a diagram illustrating a state in which valley-folded sheets are stacked on the sheet feed tray 3, and FIG. 5B is a diagram illustrating a state in which mountain-folded sheets are stacked on the sheet feed tray 3. FIG.

  In the image reading apparatus shown in FIG. 5A, the front end portion and the rear end portion in the sheet feeding direction with a normal sheet size are bent upward and downward in the sheet feeding tray 3 (valley folded state). Sheets are stacked.

  When receiving an image reading instruction from a host computer or the like, the CPU 20 drives the paper feed motor 6 to feed the sheet. Then, when the sheet is fed, the curvature is detected based on a signal from the light emitting / receiving unit 4.

  The sheet is fed into the image reading apparatus and then fed, and the CPU recognizes the sheet size based on a signal from the sheet size detection sensor 14 while being conveyed by the conveyance roller. Thereafter, the CPU 20 detects that the leading edge of the sheet has passed based on the output signal of the sheet detection sensor 15, and reads the image while taking the timing.

  The sheet is turned upside down via the U-shaped conveyance path, conveyed to the discharge port, and based on the information read by the light emitting / receiving unit 4 during sheet feeding, the CPU 20 normally sets the speed of the sheet discharge motor 19. Faster than the discharge speed. This is because when the sheet folded in the valley fold state is discharged by the sheet feeding unit, the leading edge may normally land on the sheet discharge tray as soon as the sheet D5 and curl. Therefore, by increasing the discharge speed, it is possible to increase the place where the discharged sheet is grounded like the sheet D4, and it is possible to prevent the sheet from being rounded during the discharge. If it is not the U-turn, when the sheet folded in the valley folded state is discharged by the sheet feeding unit, the sheet is also valley-folded at the discharge port.

  On the other hand, as shown in FIG. 5B, the front end portion and the rear end portion of the sheet feeding tray 3 of the image reading apparatus 100 with a normal sheet size are bent downward (in a mountain folded state) in the sheet feeding direction. When the sheets are stacked, similarly to the valley folded state, the sheet is turned upside down via the U-shaped conveyance path, and when the sheet is conveyed to the discharge port, it is read by the light emitting / receiving unit 4 during feeding. Based on the received information, the CPU 20 detects that the sheet is in the mountain folded state at the paper feed unit, and the speed of the paper discharge motor 19 is made lower than the normal discharge speed.

  As shown in FIG. 5B, the fold in the mountain fold state passes through the U-shaped conveyance path and is reversed to the valley fold state at the paper discharge port. Therefore, when discharged at a high speed, the sheet is curled by the air resistance. As a result, the next sheet is discharged onto the curled sheet, leading to a decrease in alignment. Therefore, in the present invention, discharging is performed at a lower speed than the normal discharging speed.

  Hereinafter, a sheet feeding / conveying operation of a sheet larger or smaller than a normal sheet size will be described. When the image reading apparatus 100 stacks a sheet (for example, A3 sheet) having a size larger than a normal size sheet (for example, A4 sheet) on the sheet feeding tray 3, the above-described step S5 is performed at the time of sheet feeding. Based on the information read by the sheet size detection sensor 14, the CPU 20 detects the sheet size in step S7 described above, and based on the information, the speed of the paper discharge motor 19 is made lower than the normal discharge speed. This is because a sheet having a large sheet size is likely to be affected by air resistance or the like at the time of discharging, and therefore needs to be discharged at a lower speed than usual.

  On the other hand, when the image reading apparatus 100 stacks a sheet (for example, a business card) having a smaller size than a normal size sheet on the sheet feeding tray 3, the information read by the sheet size detection sensor 14 at the time of sheet feeding is included. Based on this, when the CPU 20 detects the sheet size, the sheet discharge motor 19 discharges the sheet without changing the normal discharge speed. Since a sheet having a small sheet size is not easily affected by air resistance or the like during discharge, it can be discharged without any problem at a normal speed.

  Here, when the sheet size is small in the sheet feeding tray 3 and there is a curved or bent sheet, the influence of the sheet size is small, so that the above-described normal sheet size is not bent or bent. Processing is the same as the processing for changing the discharge speed.

  Hereinafter, sheet feeding / conveying operations which are larger than a normal size sheet and are bent or bent will be described. When the image reading apparatus 100 stacks sheets of a size larger than normal in the mountain folded state on the sheet feeding tray 3, when the sheet is conveyed to the discharge port, an output of the light emitting / receiving unit 4 is output during sheet feeding. Based on the signal, the CPU 20 detects the mountain folded state, and based on the signal output from the sheet size detection sensor 14, the CPU 20 determines that the sheet is a sheet having a size larger than the normal size, and the sheet discharge motor. 19 speed is made lower than usual.

  The upper and lower sides are inverted via the U-shaped conveyance path, and the folds in the mountain fold state are folded in a valley fold state at the paper discharge port. Further, since the sheet size is large, the folds are easily bent. Therefore, it is discharged at a lower speed than the normal speed.

  On the other hand, when the image reading apparatus 100 stacks sheets of a size larger than usual in the valley folded state on the paper feed tray 3, as in the case of the mountain folded state, when the sheet is conveyed to the discharge port, The CPU 20 detects the valley fold state based on signals output from the plurality of light emitting / receiving units 4 during paper feeding, and the CPU 20 determines that the sheet is larger than the normal size based on the signal output from the sheet size detection sensor. The sheet discharge motor 19 is made faster than usual.

  The upper and lower sides are inverted via the U-shaped conveyance path, and the folds in the valley fold state are folded into a mountain fold state at the paper discharge port, and the sheet size is large, so that the fold is easily bent. This further speeds up the landing of the sheet and increases the possibility of curling on the paper discharge tray. Therefore, it is discharged at a faster speed than usual.

  Here, when a folded sheet and a valley folded sheet are mixedly loaded as a curved / bent sheet, the discharge speed of the next sheet is decreased after increasing the discharge speed for a certain sheet. In this case, there is no problem even if the feeding speed is constant because the interval between the two sheets is widened. However, when the discharge speed is lowered and the next sheet is raised, the discharge motor 19 is slowed down. If the pickup roller 5 feeds paper at the same speed, the gap between the sheets becomes narrow due to the difference in the conveyance speed, and there is a possibility of collision when the next sheet is discharged.

  In addition, when a curved or bent sheet is discharged to the discharge tray at a low speed, if the next sheet is transported at a speed higher than usual, the sheet is not completely placed on the discharge tray. Then, the next sheet is discharged, which may deteriorate the alignment when stacked.

  Therefore, when the discharge speed is once slowed, the CPU 20 changes the speed of the paper feed motor 6 when the CPU 20 feeds the next sheet from the sheet size information obtained by the sheet size detection sensor 14 and the information that the sheet has passed. By doing so, the timing of raising and lowering the pickup roller 5 is delayed, and the sheet interval is adjusted to be larger than a predetermined value.

  As a result, even if the speed of the discharge motor 19 is decreased, the interval between the trailing edge of the sheet and the leading edge of the succeeding sheet does not become smaller than a predetermined value in the conveyance path, so that the next sheet collides with the discharged sheet. Can be prevented.

  As described above, according to the present embodiment, the alignment of the sheets discharged from the image reading apparatus 100 can be improved regardless of the state of the sheets fed into the image reading apparatus 100.

  In this embodiment, the paper feed timing is changed by controlling the raising and lowering of the pickup roller to increase the paper interval. However, it is also possible to increase the paper interval by changing the rotation speed of the pickup roller. You may use both together. Also in this case, the CPU 20 functions as a paper feed control unit. Further, the sheet size detection sensor can be replaced by an image reading unit. These controls can be carried out even when a plurality of curved and bent sheets are mixed. Moreover, although this embodiment demonstrated the apparatus provided with the U-shaped conveyance path, this invention is applicable also to the apparatus which is not provided with a U-shaped conveyance path. In that case, acceleration and deceleration may be controlled in consideration of the fact that a sheet that has been folded into a fold and a valley at the sheet feeding unit is also folded into a fold and a valley at the sheet discharge unit.

<Second Embodiment>
FIG. 6 is a diagram illustrating a configuration of an image reading apparatus 200 according to the second embodiment. FIG. 6A shows before paper feeding in the image reading apparatus 200, and FIG. 6B shows that paper is being fed.

  In this embodiment, the image reading apparatus 200 feeds the curved sheet D1 sheet by sheet by moving the pickup roller 5 up and down by driving the sheet feeding motor 6. In addition, the image reading apparatus 100 according to the first embodiment includes the light emitting / receiving unit 4 that detects the direction and amount of bending or bending of the sheet. However, in the present embodiment, the light receiving / emitting unit 4 includes. Absent. As an alternative, the image reading apparatus 200 includes a lever 23 that is pushed up by the sheet and rotates in the conveyance direction in order to rotate the rotation shaft of the variable resistor 24.

  As shown in FIG. 6A, when sheets D1 having a curve and a bend are stacked on the sheet feeding tray 3, the pickup roller 5 feeds the sheets D1 one by one by driving the sheet feeding motor 6. Then, as shown in FIG. 6B, the sheet D1 advances to the sheet feeding port, and the lever 23 rotates according to the bending of the sheet D1. Thereby, the bending / bending of the sheet D1 can be detected.

  As described above, according to the present embodiment, the abnormal shape of the sheet can be continuously determined with a simple configuration, and the disturbance at the time of discharge due to the abnormal shape of the sheet fed into the image reading apparatus 200 is suppressed. As a result, the alignment of the sheets discharged from the image reading apparatus 200 can be improved.

  In each of the above embodiments, the image reading apparatus such as a scanner has been described in detail. However, the present invention can be applied to an image forming apparatus such as a copying machine or a printer. In addition, the dimensions, materials, shapes, positional relationships, and the like of the components described in the above embodiments should be changed as appropriate according to conditions such as the configuration of the apparatus to which the invention is applied, and the technical scope of the present invention. Is not intended to be limited to the above-described embodiment.

1 is a side view schematically showing an image reading apparatus 100 according to a first embodiment of the present invention. 2 is a block diagram illustrating a functional configuration of the image reading apparatus 100. FIG. It is a figure which shows the control procedure of CPU20. FIG. 3 is a diagram showing a configuration of a light emitting / receiving unit 4. FIG. 4A is a diagram illustrating a state in which valley-folded sheets are stacked on the sheet feed tray 3, and FIG. 5B is a diagram illustrating a state in which mountain-folded sheets are stacked on the sheet feed tray 3. It is a figure which shows the structure of the image reading apparatus 200 which concerns on 2nd Embodiment. (A) is a figure which shows an example of the sheet | seat detection process by the light emitting / receiving part 4, (b) is a figure which shows the detection result in the light receiving / emitting part 4. FIG. (A) is a figure which shows an example of the sheet | seat detection process by the light emitting / receiving part 4, (b) is a figure which shows the detection result in the light receiving / emitting part 4. FIG. 6 is a diagram illustrating a schematic configuration of a paper discharge tray according to Patent Document 1. FIG. It is a figure which shows the control procedure of the discharge speed which concerns on patent document 2. FIG. It is a figure which shows the control procedure of the discharge speed which concerns on patent document 3. FIG.

Explanation of symbols

3 Paper feed tray (stacking section)
4 Light emitting / receiving section (detection means)
DESCRIPTION OF SYMBOLS 5 Pickup roller 6 Paper feed motor 9-12 Conveyance roller 13 Main motor 14 Sheet size detection sensor 15, 17 Sheet detection sensor 16 Image reading part 18 Paper discharge roller 19 Paper discharge motor 20 CPU
21 Speed controller (speed control means)
22 Timing control section (paper feed control means)
23 Lever 100 Image reading device A1 Paper feeding unit (paper feeding means)
A2 discharge part (discharge means)

Claims (5)

A sheet stacking unit on which sheets are stacked;
A sheet feeding means for feeding sheets into the apparatus;
Discharging means for discharging the sheet from the apparatus;
Wherein until incorporated in said device is started feeding into the apparatus, a detecting means for detecting the shape change of the sheet you move on the sheet stacking portion in the sheet feeding means,
The detection using the detection means when discharging the sheet, which has detected a change in the shape of the sheet from when the sheet is fed into the apparatus during feeding using the detection means, to the outside of the apparatus Based on the result, speed control means for controlling the discharge speed of the sheet discharged outside the apparatus ,
A sheet feeding apparatus comprising:   According to another aspect of the present invention, there is further provided a sheet feeding control unit that controls at least one of a sheet feeding timing and a sheet feeding speed of a sheet to be fed next to the focused sheet according to a discharging speed of the focused sheet. The sheet feeding apparatus according to claim 1. The paper feed unit, before Symbol sheet stacking portion in contact with the stacked sheets to have a pick-up rows La to feed the sheet into the apparatus,
The sheet feeding apparatus according to claim 1, wherein the detection unit is disposed upstream of the pickup roller in a sheet feeding direction of the sheet.   4. The detection unit according to claim 1, wherein the detection unit detects a change in a position of a sheet fed into the apparatus by the sheet feeding unit in a direction perpendicular to a surface of the sheet. The sheet feeding apparatus according to claim 1. Image reading apparatus characterized by including a sheet feeding apparatus according to any one of claims 1 to 4.

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