Image reading device

Abstract

To provide an image reading device that allows media having a plurality of lengths to be stacked on an ejection stacker in an orderly manner.SOLUTION: An image reading device can sequentially read images of media having different lengths in a conveyance direction. When causing a driving unit driving a conveyance driving roller and an ejection driving roller to sequentially convey media at a first speed, the image reading device determines the lengths of the media in the conveyance direction on the basis of a result of detection performed by a medium detection unit, when determining that the length of a preceding medium is equal to or more than a threshold, and subsequently determining that the length of a subsequent medium is equal to or more than the threshold, performs weak deceleration control to reduce an ejection speed to eject the media from a first speed to a second speed less than the first speed, and when determining that the length of the preceding medium is equal to or more than the threshold, and subsequently determining that the length of the subsequent medium is less than the threshold, reduces the ejection speed from the first speed to a third speed slower than the second speed.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to an image reading device. [Background technology]

[0002] Image reading devices with various configurations are used in which media discharged from a discharge section are stacked in a discharge stacker. For example, Patent Document 1 discloses an image reading device configured to stack documents discharged from a first transport roller and a second transport roller as a discharge section in a paper output tray. The image reading device in Patent Document 1 can vary the document transport speed depending on the length of the document. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-103560 Summary of the Invention [Problem to be solved by the invention]

[0004] In an image reading device capable of conveying media of multiple lengths, such as the image reading device of Patent Document 1, it is difficult to stack media of multiple lengths in a well-aligned manner in the discharge stacker. The image reading device of Patent Document 1 changes the document conveyance speed when reading the image of the document according to the length of the document, but it may be difficult to stack the media in a well-aligned manner in the discharge stacker unless the discharge speed when stacking the media in the discharge stacker is reduced relative to the conveyance speed when reading the image of the document. [Means for solving the problem]

[0005] In order to solve the above problem, the image reading device of the present invention is a reading device capable of continuously reading images of media having different lengths in the conveying direction, and includes a conveying unit that conveys the medium at a first speed in a media conveying path by a drive unit, a reading unit that reads images of the medium conveyed at the first speed in the conveying path, an ejection unit that ejects the medium from which the image has been read by the reading unit to an ejection stacker by the drive unit, a media detection unit that detects the presence or absence of media, and a control unit that controls the drive unit.The control unit is characterized in that when the conveying unit continuously transports media, it determines the length of the medium in the conveying direction based on the detection result of the media detection unit, and if the length of the preceding medium is determined to be greater than or equal to a threshold and then the length of the following medium is determined to be greater than or equal to the threshold, it performs weak deceleration control to slow down the ejection speed at which the medium is ejected from the first speed to a second speed that is slower than the first speed, and if the length of the preceding medium is determined to be greater than or equal to the threshold and then the length of the following medium is determined to be less than the threshold, it performs strong deceleration control to slow down the ejection speed from the first speed to a third speed that is slower than the second speed. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 2 is a perspective view of the scanner as viewed from the front. [Figure 2] FIG. 2 is a perspective view of the scanner seen from the front with the front cover open. [Figure 3] FIG. 3 is a cross-sectional view of the document transport path of the scanner as viewed from the width direction. [Figure 4] 10A to 10C are diagrams showing variations in the posture of the device main body. [Figure 5] FIG. 2 is a block diagram showing the control system of the scanner. [Figure 6] FIG. 3 is a cross-sectional view of the discharge unit and discharge stacker of the scanner as viewed from the width direction. [Figure 7] FIG. [Figure 8] 10 is a flowchart showing an example of a discharge flow of the scanner. [Figure 9] 6 is a graph showing the rotation speeds of a transport roller and a discharge roller. [Figure 10] 9 is a flowchart showing an example of a discharge flow of a scanner different from that shown in FIG. 8. DETAILED DESCRIPTION OF THE INVENTION

[0007] The present invention will be briefly described below. The image reading device of the first aspect is a reading device capable of continuously reading images of media of different lengths in the conveying direction, and includes a conveying unit that conveys the medium at a first speed in a media conveying path by a drive unit, a reading unit that reads an image of the medium conveyed at the first speed in the conveying path, an ejection unit that ejects the medium from which the image has been read by the reading unit to an ejection stacker by the drive unit, a media detection unit that detects the presence or absence of a medium, and a control unit that controls the drive unit.When the control unit continuously conveys the medium by the conveying unit, the control unit determines the length of the medium in the conveying direction based on the detection result of the media detection unit, and if the length of the preceding medium is determined to be greater than or equal to a threshold and then the length of the following medium is determined to be greater than or equal to the threshold, performs weak deceleration control to slow the ejection speed at which the medium is ejected from the first speed to a second speed that is slower than the first speed, and if the length of the preceding medium is determined to be greater than or equal to the threshold and then the length of the following medium is determined to be less than the threshold, performs strong deceleration control to slow the ejection speed from the first speed to a third speed that is slower than the second speed.

[0008] According to this aspect, when media are continuously transported by the transport unit, based on the detection results of the media detection unit, during the period from when a medium with a length equal to or greater than a threshold is detected until a medium with a length less than the threshold is subsequently detected, the media are discharged to the output stacker at a second speed equal to or less than the first speed, which is the media transport speed when reading images. Then, during the period from when a medium with a length equal to or greater than the threshold is detected until a medium with a length less than the threshold is subsequently detected, the media are discharged to the output stacker at a third speed even slower than the second speed. That is, assuming that media are discharged at a speed slower than the media transport speed when reading images, when a shorter medium is discharged after a longer medium is discharged, the subsequently discharged medium is discharged at a significantly slower speed. The slower the media discharge speed, the longer it takes to read the image per medium, but the more aligned the media can be stacked in the output stacker. However, if a shorter medium is discharged after a longer medium, it can be difficult to stack the media in the output stacker in an aligned manner. This is because the ejection speed of all media cannot be made too slow to prevent the image reading process time per media from becoming too long, and ejecting short media while maintaining the ejection speed of long media, which are easier to stack in good alignment, can easily lead to poor alignment of only the short media. Therefore, when ejecting media of different lengths, the deterioration of alignment can be suppressed by ejecting these media at a strong deceleration rate as needed. Therefore, according to this embodiment, media of multiple lengths can be stacked in good alignment in the ejection stacker.

[0009] The image reading device of the second aspect is the first aspect, wherein the threshold value is a length from the discharge position of the discharge section in the discharge direction of the medium to the contact position with the discharge stacker.

[0010] According to this aspect, the threshold value is the distance from the discharge position of the discharge unit in the media discharge direction to the contact position with the discharge stacker. For example, when using stiff media, if the length of the media exceeds the distance from the discharge position of the discharge unit in the media discharge direction to the contact position with the discharge stacker, the media may get caught between the discharge unit and the discharge stacker, resulting in discharge problems. Furthermore, such discharge problems are more likely to occur as the discharge speed slows. Therefore, according to this aspect, it is possible to prevent media from being discharged under conditions that are likely to cause discharge problems. Furthermore, if the media is long enough to not reach the discharge stacker during discharge, it is likely to scatter during discharge. However, if the media is long enough to reach the discharge stacker, the portions in contact with the stacker generate a braking force during discharge, preventing the media from scattering.

[0011] The image reading device of the third aspect is characterized in that, in the first or second aspect, the conveying unit conveys the medium at a fourth speed slower than the first speed, the reading unit has a low-speed conveying mode in which it reads an image of the medium conveyed at the fourth speed in the conveying path, and the control unit controls the drive unit to discharge the medium to the discharge stacker at the fourth speed when the low-speed conveying mode is selected.

[0012] According to this aspect, when the low-speed transport mode is selected, the media are discharged to the discharge stacker at the fourth speed. Because the fourth speed is slower than the first speed, it is possible to reduce the possibility that the media will not be stacked in the discharge stacker in a well-aligned manner.

[0013] The image reading device of the fourth aspect is characterized in that, in any one of the first to third aspects, when the control unit causes the conveying unit to continuously convey a series of media, once strong deceleration control is adopted, the control unit continues to perform strong deceleration control for the series of media thereafter.

[0014] According to this aspect, when a series of media is continuously transported, once strong deceleration control is adopted, strong deceleration control is continued for the series of media thereafter, which simplifies the control and reduces the load on the control unit.

[0015] A fifth aspect of the image reading device is characterized in that, in any one of the first to third aspects, when the conveying unit continuously conveys a series of media, the control unit determines whether the length of the media in the conveying direction is greater than or equal to a threshold value for each sheet of the series of media after strong deceleration control has been adopted once, and performs weak deceleration control for media whose length in the conveying direction is greater than or equal to the threshold value, and performs strong deceleration control for media whose length in the conveying direction is less than the threshold value.

[0016] According to this aspect, when a series of media is continuously transported, it is determined for each medium whether the length of the medium in the transport direction is equal to or greater than a threshold, and weak deceleration control is performed for media whose length in the transport direction is equal to or greater than the threshold, and strong deceleration control is performed for media whose length in the transport direction is less than the threshold. Therefore, by determining the length of the medium individually and performing strong deceleration control only for media whose length is less than the threshold and which are likely to deteriorate alignment, it is possible to suppress the increase in the time required to read a series of media due to a decrease in the media discharge speed.

[0017] The sixth aspect of the image reading device is characterized in that, in the fourth or fifth aspect, when the control unit causes the conveying unit to continuously convey a series of media and then continuously conveys another series of media, it makes a decision to switch between weak deceleration control and strong deceleration control for each series of media.

[0018] According to this aspect, when a series of media is continuously transported by the transport unit and then another series of media is continuously transported, a decision is made to switch between weak deceleration control and strong deceleration control for each series of media. In other words, when multiple jobs are executed, the settings are reset for each job while executing the multiple jobs, so that an appropriate media discharge speed can be selected for each job.

[0019] The seventh aspect of the image reading device is characterized in that, in any one of the first to sixth aspects, the transporting unit is capable of transporting the medium by storing it in a transparent case, and the medium detection unit has a transparent case detection unit that detects the length of the medium in the transport direction based on the transport position of the transparent case.

[0020] According to this aspect, by storing the medium in a transparent case and transporting it, it becomes easier to transport media that are difficult to transport, and the length of the medium can be accurately detected even when the medium is stored in a transparent case and transported.

[0021] The image reading device of the eighth aspect is characterized in that, in any one of the first to seventh aspects, the medium detection unit has a medium end detection unit that detects the position of the end of the medium in the transport direction of the medium transported through the transport path.

[0022] According to this aspect, the medium edge detector detects the position of the edge of the medium in the transport direction, and therefore the length of the medium can be easily detected by detecting the positions of both ends of the medium in the transport direction.

[0023] The ninth aspect of the image reading device is characterized in that, in any one of the first to eighth aspects, the length of the medium in the transport direction takes into account the increase in length that occurs when the medium is transported obliquely.

[0024] According to this aspect, the length of the medium in the transport direction takes into account the increase in length due to the medium being transported at an angle. Therefore, even if the medium is transported at an angle, it is possible to prevent problems such as medium transport failure and image reading failure caused by overlapping of continuously transported media.

[0025] The image reading device of the 10th aspect is any one of the 1st to 9th aspects, and is characterized in that it is provided with a feeding unit that feeds a medium to the conveying path, and the control unit controls the feeding unit to feed the new medium so that the new medium does not reach the reading position by the reading unit before the medium on which the image has been read by the reading unit is discharged to the discharge stacker by the discharge unit.

[0026] According to this aspect, a new medium is fed so that it does not reach the reading position of the reading unit before the medium on which the image has been read by the reading unit is discharged to the discharge stacker by the discharge unit. This makes it possible to prevent media transport errors and image reading errors caused by overlapping of continuously transported media.

[0027] The present invention will be specifically described below. In the following, as an example of an image reading device, a scanner 1 capable of reading at least one of the front and back sides of a document M, which is an example of a medium, is taken as an example. The scanner 1 is a so-called document scanner that reads the document M while moving it relative to a reading means.

[0028] In the XYZ coordinate system shown in each figure, the X-axis direction is the width direction of the device and the width direction of the original. The Y-axis direction is the depth direction of the device and is the direction along the horizontal. The Z-axis direction is the direction along the vertical. The V-axis direction is the original feed direction, which is parallel to the original transport path T, which is the transport path of the original M, and the angle formed by the Y-axis direction and the Z-axis direction in particular varies depending on the attitude of the device. The V-axis direction also roughly corresponds to the discharge direction of the medium, which is the original M. In this embodiment, the +Y direction is the direction from the back to the front of the device, and the -Y direction is the direction from the front to the back of the device. Furthermore, when viewed from the front of the device, the left is the +X direction and the right is the -X direction. Furthermore, hereinafter, the direction in which the original M is transported (+V direction) may be referred to as "downstream," and the opposite direction (-V direction) may be referred to as "upstream."

[0029] First, an overview of the scanner 1 of this embodiment will be described with reference to Figures 1 to 4. In Figures 1 to 4, the scanner 1 comprises a device main body 2 and a support base 5 that rotatably supports the device main body 2. The device main body 2 is configured to comprise a lower unit 3 and an upper unit 4. As shown in Figure 4, the upper unit 4 is provided so as to be openable and closable by rotating about a rotation axis 30 relative to the lower unit 3, and opening the upper unit 4 toward the front of the device can expose a document transport path T, which will be described later.

[0030] The lower unit 3 constituting the device main body 2 is rotatably mounted on an arm 5a constituting the support base 5 via a rotation shaft 5b, and is configured to change its position by rotating. The device main body 2 of the scanner 1 according to this embodiment is capable of changing its position and is configured to be able to hold three positions using a position holding means (not shown), two of which are positioning positions when scanning a document, and the remaining one is a position when not in use. The positions shown in the center and bottom of FIG. 4 are one of the positioning positions when scanning a document, with the center view of FIG. 4 being the first scanning position and the bottom view of FIG. 4 being the second scanning position. The top view of FIG. 4 is the position when not in use. In the position when not in use, the projected area of ​​the scanner 1 on the surface on which it is placed is the smallest, and more specifically, the position in which the space occupied in the Y-axis direction is the smallest.

[0031] In the first reading position, the projection area is larger than in the non-use position, and in the second reading position, the projection area is larger than in the first reading position. Furthermore, in the first reading position, the +V direction, which is the document feed direction, faces diagonally downward, while in the second reading position, the +V direction is approximately horizontal. In this embodiment, the +V direction is approximately horizontal in the second reading position, but this is not necessarily limited to horizontal, and the +V direction may be closer to horizontal than in the first reading position.

[0032] Each posture of the device main body 2 can be held by a holding means (not shown), and the held posture can be released by a release lever (not shown). Each posture of the device main body 2 can be detected by a posture detection unit (not shown).

[0033] The upper unit 4 is equipped with a front cover 19, and the lower unit 3 is equipped with a top cover 10. The front cover 19 is rotatable about a rotation axis 30 relative to the lower unit 3 and upper unit 4, and by rotating, it can be in a closed state as shown in FIG. 1 or an open state as shown in FIG. 2. When the front cover 19 is opened, it functions as an ejection tray that receives the document M that has been read and ejected. In other words, the front cover 19 as an ejection tray also serves as an ejection stacker that can stack multiple documents M after the images have been read.

[0034] 2, the upper unit 4 is provided with an operation panel 7 on its top surface, which provides a user interface for performing various scanning settings and scanning execution operations, and for displaying the scanning setting contents, etc. In this embodiment, the operation panel 7 as an operation unit is a so-called touch panel that can perform both display and input, and serves both as an operation unit for performing various operations and a display unit for displaying various information. The operation panel 7 is exposed by opening the front cover 19.

[0035] The top cover 10 provided on the lower unit 3 is rotatable relative to the lower unit 3, and can be rotated to take a closed state as shown in FIG. 1 or an open state as shown in FIGS. 2 and 3. When opened, the top cover 10 functions as a document support tray that supports the document M to be fed. As shown in FIG. 2, it is equipped with edge guides 12a and 12b that guide the side edges of the document M. A feed opening 6 that leads to the inside of the device body 2 is provided at the top of the device body 2, and the document M placed on the top cover 10 is fed from the feed opening 6 into the device body 2.

[0036] Next, the document transport path in the scanner 1 will be described, mainly with reference to Fig. 3. The document transport path T is a substantially linear document transport path formed between the lower unit 3 and the upper unit 4. The document transport path T is closest to vertical when the device main body 2 is in the non-use position as shown in the upper diagram of Fig. 4, has an inclination angle of nearly 45° when the device main body 2 is in the first reading position as shown in the center diagram of Fig. 4, and is nearly horizontal when the device main body 2 is in the second reading position as shown in the lower diagram of Fig. 4.

[0037] The above-mentioned top cover 10 is provided at the most upstream of the document transport path T, and on the downstream side of the top cover 10, there are provided a feed roller 14 that feeds the document M placed on the top cover 10 downstream, and a separation roller 15 that nips the document M between the feed roller 14 and the separation roller 15 to promote separation of the document M. The separation roller 15 is pressed toward the feed roller 14 by a load applying means (not shown), and a braking force is applied to the rotation shaft 15a.

[0038] The feed roller 14 comes into contact with the lowermost document M among the documents M placed on the top cover 10. Therefore, when multiple documents M are placed on the top cover 10, the documents M are fed downstream in order starting from the lowermost document M.

[0039] A flap 31 is provided upstream of the separation roller 15 in the document transport path T, and the flap 31 prevents the document M set on the top cover 10 from contacting the separation roller 15 in a feeding standby state. The flap 31 is rotatable around a rotation shaft 31a, and before feeding starts, its lower end engages with the set guide 29, preventing it from rotating clockwise in Figure 3. Before feeding starts, the set guide 29 supports the document M, thereby taking a first state in which the document M does not come into contact with the feed roller 14.

[0040] 3 around the rotation shaft 29a by the power of the transport motor 58 shown in FIG. 5, and assumes the second state in which the document M comes into contact with the feed roller 14. When the set guide 29 switches from the first state to the second state, the flap 31 becomes rotatable, and the leading edge of the document stack placed on the top cover 10 comes into contact with the separation roller 15.

[0041] 3, i.e., a torque in a direction that rotates the document M downstream in the feeding direction, is transmitted to the feed roller 14 from the feed motor 57 shown in FIG. 5 via the one-way clutch 32. Hereinafter, the rotation direction of the feed roller 14 when the feed roller 14 feeds the document M downstream will be referred to as the forward rotation direction, and the opposite rotation direction will be referred to as the reverse direction. Similarly, with regard to the rotation direction of the feed motor 57, the rotation direction when feeding the document M downstream will be referred to as the forward rotation direction, and the opposite rotation direction will be referred to as the reverse direction.

[0042] A one-way clutch 32 is provided in the drive force transmission path between the feed roller 14 and the feed motor 57, so that the feed roller 14 does not rotate in the reverse direction even when the feed motor 57 rotates in the reverse direction. Furthermore, when the feed motor 57 is stopped, the feed roller 14 comes into contact with the document M being conveyed and can be rotated in the forward direction by the feed roller 14.

[0043] Next, a torque limiter 33 is provided for the separation roller 15. When no document M is interposed between the feed roller 14 and the separation roller 15, or when only one document M is interposed, the rotational torque of the feed roller 14 attempting to rotate the separation roller 15 in the clockwise direction in FIG. 3 exceeds the upper torque limit value of the torque limiter 33, causing slippage at the torque limiter 33, and the separation roller 15 is rotated in conjunction with the feed roller 14.

[0044] When a second or subsequent sheet of original M, in addition to the original M to be fed, enters between the feed roller 14 and the separation roller 15, slippage occurs between the originals, causing the separation roller 15 to stop. As a result, the second or subsequent sheet of original M that would otherwise be fed in multiple passes is returned upstream, preventing multiple passes.

[0045] The above-described top cover 10, feed roller 14, and separation roller 15, as well as the pair of transport rollers 16, pair of discharge rollers 17, and front cover 19 as a stacker, which will be described later, constitute a medium feeding device 9 that feeds documents M, which are an example of a medium. From another perspective, the medium feeding device 9 can also be considered as a device in which the reading unit 20, which functions as a document reading function, has been removed from the scanner 1. Alternatively, even if the scanner 1 is provided with the reading unit 20, which functions as a document reading function, the scanner 1 itself can also be considered as a document feeding device from the perspective of document feeding.

[0046] Next, provided downstream of the feed roller 14 are a pair of transport rollers 16, a reading unit 20 that reads an image of the document, and a pair of discharge rollers 17. The pair of transport rollers 16 includes a transport drive roller 16a that is driven to rotate by a transport motor 58, and a transport driven roller 16b that rotates in response to the drive roller 16a. The document M nipped by the feed roller 14 and the separation roller 15 and fed downstream is nipped by the pair of transport rollers 16 and transported to a position facing the upper sensor unit 20A and the lower sensor unit 20B that are located downstream of the pair of transport rollers 16.

[0047] The reading unit 20 includes an upper sensor unit 20A located above the document transport path T and provided in the upper unit 4, and a lower sensor unit 20B located below the document transport path T and provided in the lower unit 3. The upper sensor unit 20A has a sensor module 21A, and the lower sensor unit 20B has a sensor module 21B. In this embodiment, the sensor modules 21A and 21B are contact-type image sensor modules. The upper surface of the document M is read by the sensor module 21A located above the document transport path T, and the lower surface of the document M is read by the sensor module 21B located below the document transport path T. The document read surface by the upper sensor unit 20A and the document read surface by the lower sensor unit 20B form a plane parallel to the document transport path T.

[0048] Upper sensor unit 20A is provided with background plate 22A at a position facing sensor module 21B provided in lower sensor unit 20B, and lower sensor unit 20B is provided with background plate 22B at a position facing sensor module 21A provided in upper sensor unit 20A. Background plates 22A and 22B are reference plates read by the opposing sensor modules for shading correction, and can be, for example, white, gray, black, or other resin plates or metal plates painted white, gray, black, or other colors.

[0049] The background plates 22A and 22B are rotatably mounted by the power of a motor (not shown), and by rotating, they can be switched between a facing state in which they face the opposing sensor module as shown by the solid line, and a non-facing state in which the facing state is canceled as shown by the two-dot chain line. The background plates 22A and 22B are white, for example, and in the facing state, a white reference value can be obtained, and in the non-facing state, a black reference value can be obtained.

[0050] After the image on at least one of the upper and lower surfaces of the document M is read by the reading unit 20, the document M is nipped by a pair of discharge rollers 17 serving as a discharge unit located downstream of the reading unit 20, and is discharged from a discharge opening 18. The pair of discharge rollers 17 includes a discharge drive roller 17a that is driven to rotate by a conveyance motor 58, and a discharge driven roller 17b that is driven to rotate.

[0051] As described above, in the scanner 1 of this embodiment, the drive unit that drives the transport drive roller 16a and the drive unit that drives the discharge drive roller 17a are both transport motors 58. However, this configuration is not limited to this, and the drive unit that drives the transport drive roller 16a and the drive unit that drives the discharge drive roller 17a may be provided separately.

[0052] As shown in Figure 2, the front cover 19 serving as a stacker is provided with a stopper 100 as a regulating section that regulates the movement of the original M in the discharge direction so that the original M, whose image has been read by the reading section 20, is not discharged beyond the front cover 19. The stopper 100 is rotatable about a first rotation shaft 101 along the X direction and can be displaced between a storage state in which the stopper 100 is stored in the front cover 19 and a restricted state in which the stopper 100 stands up from the front cover 19 and can function as a restricting portion. The solid lines in FIG. 2 represent the storage state in which the stopper 100 is stored in the front cover 19, and the dashed lines in FIG. 2 represent the restricted state in which the stopper 100 stands up from the front cover 19 and can function as a restricting portion. The front cover 19 is configured to be extendable and retractable by sliding multiple trays, and can be extended from the retracted state shown in FIG. 2. As the front cover 19 extends, the position of the stopper 100 also moves from the position shown in FIG. 2 to a position where the distance from the discharge roller pair 17 increases.

[0053] Next, the control system of the scanner 1 will be described with reference to Fig. 5. The control unit 50 performs various controls of the scanner 1, including feeding, conveying, and discharging control of the document M, as well as reading control. Signals are input to the control unit 50 from the operation panel 7, and signals for realizing the display of the operation panel 7, particularly the user interface, are sent from the control unit 50 to the operation panel 7.

[0054] The control unit 50 controls the feed motor 57, the transport motor 58, and the cam motor 59. In this embodiment, each motor is a DC motor. Read data from the reading unit 20 is input to the control unit 50, and a signal for controlling the reading unit 20 is sent from the control unit 50 to the reading unit 20. Signals from these detection units, namely the placement detection unit 54, the double feed detection unit 51, the first document detection unit 52, and the second document detection unit 53, are also input to the control unit 50. Detection values ​​from rotary encoders (not shown) provided for each of the feed motor 57, the transport motor 58, and the cam motor 59 are also input to the control unit 50, which enables the control unit 50 to grasp the amount of rotation of each motor and, ultimately, the amount of movement of the driven object.

[0055] The control unit 50 includes a CPU 60, a flash ROM 61, and a RAM 62. The CPU 60 performs various arithmetic processing in accordance with programs stored in the flash ROM 61, and controls the overall operation of the scanner 1. The flash ROM 61, which is an example of a storage means, is a non-volatile memory that can be read and written. Various setting information input by the user via the operation panel 7 is also stored in the flash ROM 61. Various information is temporarily stored in the RAM 62, which is an example of a storage means. The control unit 50 includes an interface 63, and is capable of communicating with an external computer 90 via this interface 63.

[0056] Next, with reference to FIGS. 6 and 7 , the document transport path T, which is the transport path of the scanner 1 of this embodiment, the pair of discharge rollers 17, which is the discharge unit, and the front cover 19, which is the discharge stacker, will be described in detail. As shown in FIG. 6 , the document M, whose image has been read, is discharged from a nip position P1, which is the discharge position by the pair of discharge rollers 17, toward a contact position P2 with the front cover 19, which is on an extension of the document transport path T and on an extension in the V-axis direction. If the document M has a length in the transport direction that is longer than the length L1 from the nip position P1 to the contact position P2, after its leading edge Ma contacts the contact position P2, it moves on the front cover 19 while sliding on the surface of the front cover 19 and is stacked on the front cover 19. If the document M has a length in the transport direction that is shorter than the length L1 from the nip position P1 to the contact position P2, it is discharged onto the front cover 19 before its leading edge Ma contacts the contact position P2 and is stacked on the front cover 19 as is.

[0057] 7, the scanner 1 of this embodiment has a medium end detection unit 71 that detects the positions of the leading end Ma and trailing end Mb, which are the ends of the document M in the transport direction of the document M transported along the document transport path T, as a medium detection unit that detects the presence or absence of the document M in order to detect the length of the document M in the transport direction. Therefore, the scanner 1 of this embodiment can easily detect the length of the document M by detecting the positions of both end portions of the document M in the transport direction.

[0058] Furthermore, the pair of transport rollers 16, which is the transport unit of the scanner 1 of this embodiment, can transport the original M housed in a transparent case. As shown in FIG. 7 , the scanner 1 of this embodiment includes a transparent case detection unit 70 that detects the length of the original M in the transport direction based on the transport position of the transparent case as a medium detection unit that detects the presence or absence of the original M to detect the length of the original M in the transport direction. Therefore, the scanner 1 of this embodiment facilitates the transport of difficult-to-transport original M by housing the original M in a transparent case and can accurately detect the length of the original M even when the original M is housed in a transparent case. The transparent case that can be used with the scanner 1 of this embodiment has multiple holes formed in positions facing the transparent case detection unit 70 during transport, and the position of the transparent case can be detected by detecting these holes. However, there are no particular limitations on the configuration of the usable transparent case and the transparent case detection unit 70. Furthermore, the medium detection unit can also be configured to use a configuration other than the medium edge detection unit 71 and the transparent case detection unit 70, such as a contact image sensor (CIS) or encoder that reads the image of the original M.

[0059] The medium detection units (medium edge detection unit 71 and transparent case detection unit 70) in the scanner 1 of this embodiment detect the presence or absence of the original M or the transparent case, and the control unit 50 determines the length of the original M based on the detection results. Here, the length of the original M may be any of the following: the detection value of the medium detection unit itself, the detection value of the medium detection unit plus a margin due to skewed transport of the original M, or the detection value of the medium detection unit applied to existing sizes of originals such as A4 and A5. In this embodiment, the length of the original M is the detection value of the medium detection unit plus a margin due to skewed transport of the original.

[0060] 7, the scanner 1 of this embodiment has two protruding stiffening portions 72 that can stiffen the document M discharged from the transport roller pair 16. The stiffening portions 72 make the document M discharged from the transport roller pair 16 uneven when viewed from the discharge direction, so that the document M does not curl when viewed from the X-axis direction and is stacked in an appropriate state on the front cover 19.

[0061] Next, an example of the discharge flow of the scanner 1 of this embodiment will be described according to the flowchart of Fig. 8, with reference to Fig. 9. Here, the scanner 1 of this embodiment is a reading device that can continuously read images of documents M having different lengths in the transport direction, and the flowchart of Fig. 8 shows the discharge flow of one document M out of a series of documents M corresponding to one job. In other words, the discharge flow shown in the flowchart of Fig. 8 is executed for each document M in the series.

[0062] 8 starts, first, in step S110, the process of reading the image of the original document M starts. Specifically, the original document M is fed to the original document transport path T by the feed roller 14, and the original document M is transported by the transport roller pair 16 at a first speed. The first speed here is, for example, 492 mm / sec.

[0063] Next, in step S120, the length of the original M is detected. Specifically, when the original M is housed in a transparent case and transported, the control unit 50 determines the length of the original M based on the detection result of the transparent case detection unit 70, and when the original M is transported without being housed in a transparent case, the control unit 50 determines the length of the original M based on the detection result of the medium end detection unit 71. Note that even when the original M is housed in a transparent case and transported, if the position of the transparent case and the position of the transparent case detection unit 70 are misaligned, the control unit 50 can determine the length of the original M based on the detection result of the medium end detection unit 71.

[0064] Next, in step S130, the control unit 50 determines whether the document M being read is the first sheet of a series of documents M corresponding to one job. If the control unit 50 determines that the document M is the first sheet, the process proceeds to step S200, where the document M, whose image has been read by the reading unit 20, is discharged to the front cover 19 by the pair of discharge rollers at a second speed that is lower than the first speed. Note that the second speed here is, for example, 375 mm / sec. On the other hand, if the control unit 50 determines that the document M is not the first sheet, the process proceeds to step S140.

[0065] In step S140, the control unit 50 determines whether or not any of the original documents M whose size is less than the threshold has been conveyed among the series of original documents M corresponding to one job for which image reading processing has been performed so far. The threshold here is the length L1 from the nip position P1 to the contact position P2. If the control unit 50 determines that any of the original documents M whose size is less than the threshold has not been conveyed, the process proceeds to step S200. On the other hand, if the control unit 50 determines that any of the original documents M whose size is less than the threshold has been conveyed, the process proceeds to step S150. A threshold different from that used in this embodiment may be used. For example, the threshold can be set to any size, such as A4 size or card size.

[0066] In step S150, the control unit 50 determines whether or not a document M equal to or larger than the threshold has been conveyed among the document M for which image reading processing has been performed so far among the series of document M corresponding to one job. Note that the threshold here is also the length L1 from the nip position P1 to the contact position P2. If the control unit 50 determines that a document M equal to or larger than the threshold has not been conveyed, the process proceeds to step S200. On the other hand, if the control unit 50 determines that a document M equal to or larger than the threshold has been conveyed, the process proceeds to step S160. As described above, in steps S140 and S150, it is determined whether or not a document M equal to or smaller than the threshold and a document M equal to or larger than the threshold are mixed among the series of document M corresponding to one job.

[0067] In step S160, the control unit 50 determines whether the strong deceleration monitoring is on. In other words, it determines whether step S180, which will be described later, has been executed since the discharge flow of the flowchart in Fig. 8 for a series of documents M corresponding to one job was started. If the control unit 50 determines that the strong deceleration monitoring is on, the process proceeds to step S210, and if the control unit 50 determines that the strong deceleration monitoring is not on, the process proceeds to step S170.

[0068] In step S170, the control unit 50 determines whether the document M being read is equal to or greater than the threshold. If the control unit 50 determines that the document M being read is less than the threshold, the process proceeds to step S200, and if the control unit 50 determines that the document M being read is equal to or greater than the threshold, the process proceeds to step S180.

[0069] In step S180, the strong deceleration monitoring is turned on, which controls the document M to be read next time and thereafter so that it is discharged to the front cover 19 at a third speed, which is slower than the second speed. As described above, the strong deceleration monitoring is turned on when a mixture of document M below the threshold and document M above the threshold is loaded and the document M above the threshold is conveyed. After step S180 is executed, the process proceeds to step S200.

[0070] In step S210, the control unit 50 determines whether or not an original M less than the threshold value has been transported since the strong deceleration monitoring ON state was entered. If the control unit 50 determines that an original M less than the threshold value has not been transported since the strong deceleration monitoring ON state was entered, the process proceeds to step S200, whereas if the control unit 50 determines that an original M less than the threshold value has been transported since the strong deceleration monitoring ON state was entered, the process proceeds to step S200. In other words, as long as an original M equal to or greater than the threshold value is being transported even after the strong deceleration monitoring ON state was entered, the original M will be discharged to the front cover 19 at the second speed.

[0071] In step S220, the document M, whose image has been read by the reading unit 20, is discharged to the front cover 19 by the discharge roller pair at a third speed. The third speed here is, for example, 101 mm / sec. Then, with the completion of steps S200 and S220, the discharge flow for one document in the flowchart of FIG. 8 ends, and the image reading process from steps S110 to S220 for the next document M in the series of documents M corresponding to one job begins. Here, if the strong deceleration monitoring is ON, the strong deceleration monitoring is temporarily turned OFF each time the discharge flow for one document in the flowchart of FIG. 8 ends. In the flowchart of FIG. 8, if the first document M has a length equal to or greater than the threshold and the second document M has a length less than the threshold, the document M is discharged to the front cover 19 at the second speed. However, in this case, the document M may be discharged to the front cover 19 at the third speed.

[0072] Here, for example, when the discharge flow of the flowchart in Figure 8 is executed for a series of four originals M corresponding to one job, if the first sheet is below the threshold, the second sheet is equal to or greater than the threshold, the third sheet is below the threshold, and the fourth sheet is equal to or greater than the threshold, the first sheet is discharged at the second speed, the second sheet is also discharged at the second speed and the strong deceleration monitoring is turned on, and the third and fourth sheets are discharged at the third speed.

[0073] 8 is executed for a series of three originals M corresponding to one job, and if the first original is less than the threshold, the second original is equal to or greater than the threshold, and the third original is equal to or greater than the threshold, the first original is discharged at the second speed, and the second original is also discharged at the second speed, and the strong deceleration monitoring is turned on. Here, although the strong deceleration monitoring is on for the third original, the third original is equal to or greater than the threshold, and no original M has been conveyed that is less than the threshold since the strong deceleration monitoring was turned on, so the third original is discharged at the second speed.

[0074] Furthermore, for example, when the discharge flow of the flowchart in Figure 8 is executed for a series of three originals M corresponding to one job, if the first original is above the threshold, the second original is above the threshold, and the third original is above the threshold, there is no original M transported that is below the threshold, so the strong deceleration monitoring is not turned on, and all three originals are discharged at the second speed.

[0075] 9 is a graph showing the relationship between the rotational speeds of the transport drive roller 16a and the discharge drive roller 17a and the elapsed time when the nth sheet of a series of documents M corresponding to one job is discharged at the second speed and the (n+1)th sheet is discharged at the third speed. In the scanner 1 of this embodiment, the transport drive roller 16a and the discharge drive roller 17a have the same outer diameter, and both are rotated at the same rotational speed and timing by the transport motor 58, which is a common drive unit.

[0076] The nth sheet of original M is transported at a first speed while its image is being read. The first speed region corresponding to the nth sheet of original M in FIG. 9 corresponds to the time period during which the image on the nth sheet of original M is being read. When image reading on the nth sheet of original M is completed, the transport drive roller 16a and the discharge drive roller 17a are slightly decelerated, and the nth sheet of original M is discharged from the discharge roller pair 17 at a second speed. The period during which the transport drive roller 16a and the discharge drive roller 17a are slightly decelerated corresponds to a length with a margin relative to the length of the original M in the transport direction. This is because, if the original M is transported skewed, the apparent length of the original M transported along the original transport path T becomes longer. Specifically, for example, the margin is the apparent length that becomes longer than the actual length when the original M is transported skewed at 20°. After the nth sheet of original M is discharged, the rotational speed of the transport drive roller 16a and the discharge drive roller 17a is returned to normal, and image reading on the n+1th sheet of original M begins. The reason why the apparent length that becomes longer than the actual length when the original M is transported at an angle of 20° is used as the margin is that in the scanner 1 of this embodiment, if the original M is transported at an angle of up to 20°, the image read by the reading unit 20 can be corrected using firmware or an application installed on the external computer 90.

[0077] The n+1th sheet of original M is also transported at the first speed while its image is being read. The first speed region corresponding to the n+1th sheet of original M in FIG. 9 corresponds to the time period during which the image of the n+1th sheet of original M is being read. Then, when image reading of the n+1th sheet of original M is completed, the transport drive roller 16a and the discharge drive roller 17a strongly decelerate, and the n+1th sheet of original M is discharged from the discharge roller pair 17 at the third speed. Here, like the weak deceleration period, the strong deceleration period of the transport drive roller 16a and the discharge drive roller 17a corresponds to a length of the original M in the transport direction with a margin. Then, after the n+1th sheet of original M is discharged, the rotational speed of the transport drive roller 16a and the discharge drive roller 17a is returned to normal, and image reading of the n+2th sheet of original M begins. Note that, as described above, once the strong deceleration monitoring is turned on and original M is discharged at the third speed, subsequent originals M are also discharged at the third speed.

[0078] As described above, in the scanner 1 of this embodiment, the transport drive roller 16a, which transports the document M along the document transport path T, and the pair of discharge rollers 17, which discharge the document M, are synchronized. The reading unit 20 in the scanner 1 of this embodiment is premised on reading the image of the document M transported at a constant speed. Therefore, the control unit 50 controls the transport speed of the document M at the image reading position to be constant at the first speed. That is, the drive time of the transport drive roller 16a and the discharge drive roller 17a when discharging the nth document M at the second speed in FIG. 9 and the time from discharging the nth document M to feeding the n+1th document M are set to satisfy this premise. In other words, the control unit 50 controls the transport speed so that the gap between the nth document M and the n+1th document M does not become too narrow, causing the document M to be transported slower than the first speed at the reading position of the reading unit 20.

[0079] As described above, the transport drive roller 16a that transports the document M along the document transport path T and the discharge drive roller 17a that discharges the document M may be configured to be driven by separate drive units. In this case, control is still required to prevent the document M from being transported slower than the first speed at the reading position by the reading unit 20, but the time from when the nth document M is discharged to when the (n+1)th document M is fed may be changed from that of the scanner 1 of this embodiment. This is because, even if the discharge speed of the preceding document M by the discharge drive roller 17a is slowed, the transport speed of the following document M by the transport drive roller 16a can be kept the same as the transport speed during image reading, as long as the preceding document M and the following document M do not overlap.

[0080] To summarize, as described above, the scanner 1 of this embodiment is a reading device capable of continuously reading images of documents M having different lengths in the transport direction, and is equipped with a pair of transport rollers 16 that transports the documents M at a first speed along the document transport path T by a transport motor 58, a reading unit 20 that reads images of the documents M transported at the first speed along the document transport path T, a pair of discharge rollers 17 that discharge the documents M whose images have been read by the reading unit 20 by the transport motor 58 onto the front cover 19, and a transparent case detection unit 70 and a medium end detection unit 71 which are medium detection units. As shown in the flowchart of Figure 8, the control unit 50 determines the length of the original M based on the detection results of the medium detection unit, and if it is determined that the length of the preceding original M is equal to or greater than a threshold, and then the length of the succeeding original M is equal to or greater than the threshold, it performs weak deceleration control to slow the discharge speed at which the original M is discharged from a first speed to a second speed that is less than the first speed, and if it is determined that the length of the preceding original M is equal to or greater than the threshold, then it performs strong deceleration control to slow the discharge speed from the first speed to a third speed that is slower than the second speed.

[0081] That is, the scanner 1 of this embodiment assumes that the original M is discharged at a speed equal to or slower than the conveyance speed of the original M when reading an image. When a shorter original M is discharged after a longer original M, the document M is discharged by strongly decelerating the document M. The slower the document M discharge speed, the longer it takes to read the image per document M, but the document M can be stacked in good alignment on the front cover 19. However, if a shorter original M is discharged after a longer original M, it can be difficult to stack the documents in good alignment on the front cover 19. This is because the discharge speed of all documents M cannot be slowed down too much to prevent the image reading process per document M from becoming too long. Furthermore, if a shorter original M is discharged while maintaining the discharge speed of a longer original M, which is easier to stack in good alignment, the alignment of only the shorter original M is likely to deteriorate. Therefore, when discharging documents M of different lengths, the scanner 1 of this embodiment can suppress deterioration of alignment by strongly decelerating the documents M as needed. Therefore, the scanner 1 of this embodiment can stack documents M of different lengths on the front cover 19 in good alignment.

[0082] As described above, the threshold value is the length L1 from the nip position P1, which is the discharge position of the discharge roller pair 17 in the discharge direction of the document M, to the contact position P2 with the front cover 19. For example, when using a stiff document M, if the length of the document M exceeds the length L1 from the nip position P1 to the contact position P2 in the discharge direction of the document M, the document M may get caught between the discharge roller pair 17 and the front cover 19, resulting in a discharge failure. Such a discharge failure is more likely to occur as the discharge speed decreases. Therefore, the scanner 1 of this embodiment sets the threshold value to the length L1 from the nip position P1 to the contact position P2, thereby preventing the document M from being discharged under conditions that are likely to result in a discharge failure. Furthermore, if the document M is long enough to not reach the front cover 19 during discharge, it is likely to scatter during discharge. However, if the document M is long enough to reach the front cover 19, the portions of the document M in contact with the front cover 19 generate a braking force during discharge, preventing the document M from scattering.

[0083] Here, the scanner 1 of this embodiment has a low-speed transport mode in which the transport roller pair 16 transports the document M at a fourth speed slower than the first speed, and the reading unit 20 reads an image of the document M transported at the fourth speed on the document transport path T. Note that the fourth speed here is, for example, 370 mm / sec. When the low-speed transport mode is selected, the control unit 50 controls the transport motor 58 to discharge the document M onto the front cover 19 at the fourth speed. In this way, the scanner 1 of this embodiment has a low-speed transport mode, and by selecting the low-speed transport mode, the document M is discharged onto the front cover 19 at the fourth speed slower than the first speed, which makes it possible to prevent the document M from being unable to be stacked in good alignment on the front cover 19.

[0084] As described above, the scanner 1 of this embodiment does not execute the discharge flow shown in the flowchart of FIG. 8 when the low-speed transport mode is selected. In other words, if the transport speed of the original M during image reading is slower than a predetermined speed, the discharge speed of the original M is not slowed down below the transport speed of the original M during image reading. The predetermined speed is not particularly limited, but may be, for example, 375 mm / sec. It may also be the transport speed during image reading at a resolution of 300 dpi. Note that the higher the resolution, the slower the transport speed generally becomes. In other words, if there are multiple image reading modes with different transport speeds, and one or more of these modes employ a first speed (the transport speed of the original M during image reading), a second speed (a discharge speed equal to or slower than the first speed due to weak deceleration), and a third speed (a discharge speed slower than the second speed due to strong deceleration) as shown in the flowchart of FIG. 8, this is included in the present invention.

[0085] Furthermore, for example, when a series of documents M are continuously transported by the transport roller pair 16 as shown in Fig. 8, and then a series of documents M are continuously transported as shown in Fig. 8, the control unit 50 determines whether to switch between weak deceleration control and strong deceleration control for each series of documents M. In other words, when the scanner 1 of this embodiment executes multiple jobs, it executes the multiple jobs while resetting the settings related to strong deceleration monitoring for each job. In this way, it is possible to select an appropriate discharge speed for the documents M for each job.

[0086] Furthermore, as described above, both the weak deceleration period and the strong deceleration period are periods that take into account the length of the original document M in the transport direction, including a margin for the length detected by the medium detection unit. In other words, the length of the original document M in the transport direction is a length that takes into account the increase in length that occurs when the original document M is transported skewed. Therefore, even when the original document M is transported skewed, the scanner 1 of this embodiment can prevent problems such as poor transport of the original document M and poor image reading caused by overlapping of consecutively transported original documents M.

[0087] As described above, the scanner 1 of this embodiment is also provided with the feed roller 14 as a feed unit that feeds the document M to the document transport path T. The control unit 50 controls the feed roller 14 to feed the new document M so that the new document M does not reach the reading position by the reading unit 20 before the document M whose image has been read by the reading unit 20 is discharged to the front cover 19 by the discharge roller pair 17. Therefore, the scanner 1 of this embodiment can prevent problems such as poor transport of the document M or poor image reading caused by overlapping of consecutively transported documents M.

[0088] 8, when a series of documents M is continuously transported by the transport roller pair 16, once the control unit 50 has adopted strong deceleration control, it can continue to execute strong deceleration control for the subsequent series of documents M. By executing such a discharge flow, the control can be simplified and the load on the control unit 50 can be reduced.

[0089] On the other hand, when a series of documents M is continuously transported by the transport roller pair 16, the control unit 50 can determine whether the length of the document M in the transport direction is equal to or greater than a threshold for each document M in the series after the strong deceleration control has been applied once, and can execute weak deceleration control for documents M whose length in the transport direction is equal to or greater than the threshold, and execute strong deceleration control for documents M whose length in the transport direction is less than the threshold. By executing such a discharge flow, strong deceleration control is executed only for documents M whose length is less than the threshold, which is likely to deteriorate alignment, and it is possible to suppress an increase in the time required for the reading process of a series of documents M due to a decrease in the discharge speed of the documents M.

[0090] The discharge flow for carrying out the above control will be explained below with reference to the flowchart in Fig. 10. In the flowchart in Fig. 10, the same steps as those in the flowchart in Fig. 8 are assigned the same step numbers. Therefore, explanations of steps with step numbers that have already been explained will be omitted.

[0091] In the discharge flow in the flowchart of Fig. 10, after step S150 is completed, the process proceeds to step S190. Then, in step S190, the control unit 50 determines whether the document M being read is equal to or greater than a threshold. If the control unit 50 determines that the document M being read is less than the threshold, the process proceeds to step S200, and if the control unit 50 determines that the document M being read is equal to or greater than the threshold, the process proceeds to step S220. As shown in the flowchart of Fig. 10, in the discharge flow, strong deceleration monitoring is not turned on or off, and it is determined for each document M being read whether the document M being read is equal to or greater than the threshold.

[0092] The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the invention as defined in the claims, and it goes without saying that these modifications are also included within the scope of the present invention. Furthermore, in the above-described embodiment, the medium feeding device 9 is applied to a scanner, but it can also be applied to a recording device, such as a printer, equipped with a recording head that records on recording paper as an example of a medium. Furthermore, if the first sheet of paper is shorter than the threshold, it is also possible to configure the document M to be discharged at the third speed from the first sheet. [Explanation of symbols]

[0093] 1...scanner, 2...device main body, 3...lower unit (storage section), 4...upper unit, 5...support base, 5a...arm section, 5b...rotating shaft, 6...feed port, 7...operation panel, 9...medium feeding device, 10...top cover, 12a and 12b...edge guides, 14...feed roller (feed section), 15...separation roller, 15a...rotating shaft, 16...pair of transport rollers (transport section), 16a...transport drive roller, 16b...transport driven roller, 17...pair of discharge rollers (discharge section), 17a...discharge drive roller, 17b...discharge driven roller, 18...discharge port, 19...front cover (discharge stacker), 20...reading section, 20A...upper sensor unit, 20B...lower sensor unit, 21A and 21B...sensor module, 22A and 22B...background Plate, 29...set guide, 29a...rotating shaft, 30...rotating shaft, 31...flap, 31a...rotating shaft, 32...one-way clutch, 33...torque limiter, 50...controller, 51...multiple feed detector, 52...first document detector, 53...second document detector, 54...placement detector, 57...feed motor, 58...transport motor (drive unit), 59...cam motor, 60...CPU, 61...flash ROM, 62...RAM, 63...interface, 70...transparent case detector (media detector), 71...media edge detector (media detector), 72...stiffener, 90...external computer, 100...stopper, 101...first rotating shaft, 191...recess (storage section), M...document (media), Ma...leading edge (edge), Mb...trailing edge (edge), T...document transport path (transport path)

Claims

1. An image reading device capable of continuously reading images on a medium, a transport unit that transports the medium at a first speed in a medium transport path; a reading unit that reads an image on a medium transported at the first speed in the transport path; a discharge unit that discharges the medium from which the image has been read by the reading unit to a discharge stacker; a medium detection unit that detects the presence or absence of a medium; a control unit; When the control unit causes the transport unit to transport the medium, the control unit determining the length of the medium in the transport direction based on The control unit According to the result of determining the length of the medium, the paper discharge speed is changed to a second speed slower than the first speed. or a third speed slower than the second speed, discharging the medium by the discharge unit at the determined paper discharge speed; An image reading device characterized by:

2. In the image reading device according to claim 1, After it is determined that the length of the first transported preceding medium is equal to or greater than the threshold, the length of the succeeding medium is If it is determined that the speed is equal to or greater than the threshold, the ejection speed at which the subsequent medium is ejected is changed from the first speed to the first speed. performing weak deceleration control to decelerate the vehicle to a second speed that is lower than the normal speed; After it is determined that the length of the first transported preceding medium is equal to or greater than the threshold, the length of the succeeding medium is If it is determined that the discharge rate is less than the threshold value, the discharge rate is changed from the first rate to a rate slower than the second rate. performing strong deceleration control to decelerate to a third speed; An image reading device characterized by:

3. In the image reading device according to claim 1 or 2, The transport unit transports the medium at a fourth speed that is slower than the first speed, and the reading unit a low-speed transport mode for reading an image on a medium transported at the fourth speed in a transport path; When the low-speed transport mode is selected, the control unit Regardless of the speed set, the previous speed will be controlling the ejection section to eject the medium to the ejection stacker at the fourth speed; An image reading device characterized by:

4. 3. The image reading apparatus according to claim 2, The threshold value is the distance between the ejection position of the ejection unit and the ejection stacker in the ejection direction of the medium. An image reading device characterized in that the length from the first contact point to the second contact point is 1 / 2.

5. 5. The image reading apparatus according to claim 2, wherein: When the conveyance unit conveys a series of media continuously, the control unit After the control is adopted, the strong deceleration control is continuously performed for the subsequent series of media. An image reading device characterized by:

6. 5. The image reading apparatus according to claim 2, wherein: When the conveyance unit conveys a series of media continuously, the control unit After the control is adopted, the media in the transport direction for each of the series of media is The length of the medium in the transport direction is determined to be equal to or greater than the threshold value. If the length of the medium in the transport direction is less than the threshold, weak deceleration control is performed. An image reading apparatus characterized by performing speed control.

7. 7. The image reading apparatus according to claim 5, The control unit causes the conveyance unit to continuously convey a series of media, and then conveys a series of media. When media are transported continuously, switching between weak deceleration control and strong deceleration control for each series of media An image reading device characterized by executing a judgment.

8. 8. The image reading device according to claim 1, the transport unit is capable of transporting a medium housed in a transparent case, The medium detection unit detects the length of the medium in the conveying direction based on the conveying position of the transparent case. An image reading device characterized by having a transparent case detection unit that detects a transparent case.

9. 9. The image reading device according to claim 1, The medium detection unit detects the leading edge and the trailing edge of the medium in the transport direction of the medium transported through the transport path. and a medium edge detection unit for detecting the position of the trailing edge.

10. 10. The image reading device according to claim 1, The length of the medium in the transport direction is determined by adding the detection medium to the length of the medium in the transport direction. The length of the image reading sheet is the length of the sheet that is increased by the oblique conveyance. Removal device.

11. 11. The image reading device according to claim 1, a feeding unit that feeds a medium to the transport path; The control unit is configured to: Before being discharged to the discharge stacker, a new medium is placed at a position where the reading unit reads the medium. The feeding unit is controlled to feed the new medium so that the new medium does not reach the predetermined position. An image reading device.

12. a transport unit that transports the medium at a first speed in a medium transport path; a recording unit that records on the medium; a discharge unit that discharges the medium recorded by the recording unit to a discharge stacker; a medium detection unit that detects the presence or absence of a medium; a control unit; When the conveyance unit conveys the medium continuously, the control unit Based on the detection result, the length of the medium in the transport direction is determined; The control unit According to the result of determining the length of the medium, the paper discharge speed is changed to a second speed slower than the first speed. or a third speed slower than the second speed, discharging the medium by the discharge unit at the determined paper discharge speed; A recording device characterized by:

Images