JP7670211B2 - Image reader - Google Patents

Description

The present invention relates to an image reading device that reads a document.

A scanner, which is an example of an image reading device, may be provided with an automatic document feeder (also called an ADF (Auto Document Feeder)) that automatically feeds a document as a medium, and may be configured to automatically feed and read multiple documents.
In an image reading device having such a configuration, there is a need among users to read booklets such as passports and bankbooks.

When the open pages of the booklet are read by an automatic feeder that automatically feeds multiple originals, the automatic feeder may attempt to separate the overlapping pages and feed them one by one, resulting in a state in which the open booklet cannot be fed and, furthermore, a jam may occur, damaging the pages of the booklet.
Furthermore, the opened booklet may be thick and may not enter between the two rollers of the transport roller pair that transports the medium, resulting in a non-feed state.

Here, there is a scanner capable of feeding the booklet with the automatic feeder, which is configured to place the booklet with the page to be read open in a transparent holder and feed it with the automatic feeder (for example, Patent Document 1).

JP 2016-174247 A

However, in the scanner described in Patent Document 1, which transports and reads a booklet placed in a holder, it is time-consuming to place the booklet in the holder.
Furthermore, since the booklet placed in the holder is thicker than the booklet alone, the problem of non-feed occurring at the transport roller pair is not solved.

The present invention was made in consideration of such circumstances, and its purpose is to provide an image reading device that can easily and appropriately read booklets.

To solve the above problem, the image reading device according to the first aspect of the present invention includes a reading unit that reads an image on a medium, a medium feeding unit that can select between a first feeding mode in which a stack of multiple media is separated and fed when feeding the medium placed on a medium placement unit toward the reading unit, and a second feeding mode in which the stack of media is fed together without being separated, a drive roller provided downstream of the medium feeding unit in the medium feeding direction, and a driven roller that rotates in response to the rotation of the drive roller, and is characterized in that when the medium feeding unit feeds in the second feeding mode, the driven roller drives in the rotation direction in which the medium is transported.

According to this aspect, when the medium feeding unit feeds in the second feeding mode, the driven roller is driven in the rotational direction of transporting the medium. This makes it possible to easily set and feed a stack of media (e.g., booklets such as passports or bankbooks, or stacks of documents) that may cause feeding problems or jams if the stack is separated and fed one by one by executing the second feeding mode. In addition, this reduces the risk of the stack of media, which is thicker than a single medium, not entering between the drive roller and the driven roller, a so-called non-feed state, and allows for proper transport of the stack of media.

The second aspect of the present invention is characterized in that it includes a reading unit that reads an image on a medium, a medium feeding unit that can select between a first feeding mode in which a stack of multiple media is separated and fed when feeding the medium placed on a medium placement unit toward the reading unit, and a second feeding mode in which the stack of media is fed together without being separated, a drive roller provided downstream of the medium feeding unit in the medium feeding direction, and a driven roller that rotates following the rotation of the drive roller, and when the medium feeding unit feeds in the second feeding mode, the contact load applied by the driven roller to the drive roller is made smaller than the contact load when the first feeding mode is executed.

According to this aspect, when the medium feeding unit feeds in the second feeding mode, the contact load that the driven roller applies to the drive roller is made smaller than the contact load when the first feeding mode is executed. Therefore, by executing the second feeding mode, a stack of media that may cause feeding problems or jams when separated and fed one sheet at a time can be easily set and fed. In addition, the risk of the stack of media, which is thicker than media transported one sheet at a time, not entering between the drive roller and driven roller, a so-called non-feed state, is reduced, and proper transport of the stack of media can be achieved.
The contact load when the second feeding mode is executed may be smaller than the contact load when the first feeding mode is executed, and includes the case where the contact load is zero.

The third aspect of the present invention is characterized in that the second aspect is provided with a load applying means including a spring support part that is displaceable along the direction in which the driven roller applies the contact load to the drive roller, and a pressure spring that is provided between the spring support part and the driven roller and presses the driven roller, and the contact load is adjusted by displacing the spring support part.

According to this aspect, the contact load that the driven roller exerts on the driving roller can be easily adjusted.

The fourth aspect of the present invention is the second aspect, characterized in that the driven roller is configured to be movable away from the drive roller, and when the medium feeding unit performs feeding in the second feeding mode, the driven roller moves away from the drive roller.

According to this aspect, when the medium feeding unit feeds in the second feeding mode, the driven roller separates from the drive roller, so that the contact load in the second feeding mode is set to zero, further reducing the risk of non-feeding.

A fifth aspect of the present invention is characterized in that, in any one of the first to fourth aspects, the medium feeding unit includes a feed roller that feeds the medium, and a separation roller that is configured to be displaceable between a contact state in contact with the feed roller and a separated state in which the medium is separated from the feed roller, and when the medium feeding unit performs feeding in the first feeding mode, the separation roller is placed in the contact state and driven to rotate in a reverse rotation direction that is opposite to the forward rotation direction that is the rotation direction when the medium is fed in the reading direction by the reading unit, and when the medium feeding unit performs feeding in the second feeding mode, the separation roller is placed in the separated state.

According to this aspect, the medium feeding section can easily switch between the first feeding mode and the second feeding mode.

The sixth aspect of the present invention is characterized in that in the fifth aspect, a medium detection unit is provided between the medium feeding unit and the drive roller located closest to the medium feeding unit, and detects the medium, and when the medium detection unit detects the passage of the leading edge of the medium fed by the medium feeding unit in the second feeding mode, the separation roller is brought into the contact state and driven to rotate in the forward rotation direction.

According to this aspect, when the media stack fed by the feed roller has been fed to a certain extent, the separation roller can be brought into the contact state and driven to rotate in the forward rotation direction. This allows the separation roller driven to rotate in the forward rotation direction and the feed roller to apply a conveying force to the media stack.

A seventh aspect of the present invention is characterized in that in any one of the first to fourth aspects, the medium feeding unit includes a feeding roller that feeds the medium, a separation roller that is driven to rotate in a reverse rotation direction that is opposite to the forward rotation direction that is the rotation direction when feeding at least the medium in the reading direction by the reading unit, and a power transmission mechanism that has a gear train composed of multiple meshing gears and transmits power from a drive source to the separation roller, and when the medium feeding unit performs feeding in the second feeding mode, some of the gears that constitute the gear train are disengaged.

According to this aspect, the medium feeding section can easily switch between the first feeding mode and the second feeding mode.

The eighth aspect of the present invention is characterized in that, in any one of the first to seventh aspects, the reading unit includes a first reading unit that reads a first side of the medium fed by the medium feeding unit, and a second reading unit that reads a second side that is the opposite side to the first side, and is configured to be able to change the distance between the first reading unit and the second reading unit, and the medium feeding unit makes the distance wider when executing the second feeding mode than when executing the first feeding mode.

According to this aspect, the distance between the first reading unit and the second reading unit is configured to be changeable, and the distance when the medium feeding unit executes the second feeding mode is made wider than the distance when the medium feeding unit executes the first feeding mode, so that the stack of media, which is thicker than media transported one by one, can be prevented from getting caught between the first reading unit and the second reading unit, causing a jam.

A ninth aspect of the present invention is characterized in that, in any one of the first to eighth aspects, the driven roller has a page-turning mechanism.
According to this aspect, when the bundle of multiple media is a booklet, reading can be performed while automatically turning over the pages.

A tenth aspect of the present invention is characterized in that, in the ninth aspect, the pair of transport rollers is configured so that the page turning mechanism turns the topmost medium of the media stack by the driven roller that is driven to rotate in a reverse rotation direction to transport the medium in the opposite direction to the reading direction by the reading unit.
According to this aspect, the page-turning mechanism can be configured in a simple manner.

FIG. 1 is an external perspective view showing a scanner according to a first embodiment. FIG. 2 is a side cross-sectional view showing a paper transport path in the scanner according to the first embodiment. FIG. 1 is a schematic cross-sectional side view of a scanner according to a first embodiment. FIG. 11 is a schematic cross-sectional side view of a scanner according to a second embodiment. 4A to 4C are diagrams for explaining a page turning operation by a page turning mechanism. 4A to 4C are diagrams for explaining a page turning operation by a page turning mechanism. 1 is an external perspective view showing a scanner provided with an operating unit for switching the medium feeding unit between a "first feeding mode" and a "second feeding mode." FIG. 13 is a perspective view showing a state of the power transmission mechanism in a "first feeding mode" of the medium feeding section. FIG. 13 is a perspective view showing a state of the power transmission mechanism in a "second feeding mode" of the medium feeding section. 11 is an enlarged view of a main portion of the power transmission mechanism, illustrating the displacement of gears when the medium feeding section is switched between a "first feeding mode" and a "second feeding mode." FIG.

[First embodiment]
First, an image reading apparatus according to an embodiment of the present invention will be outlined.
In this embodiment, a document scanner (hereinafter simply referred to as scanner 1) capable of reading at least one of the front and back sides of a sheet of paper as a "medium" will be taken as an example of an image reading device.

Figure 1 is an external perspective view showing a scanner according to the first embodiment. Figure 2 is a side cross-sectional view showing a paper transport path in the scanner according to the first embodiment. Figure 3 is a schematic side cross-sectional view of the scanner according to the first embodiment.

In the X-Y-Z coordinate system shown in each figure, the X direction is the device width direction and the paper width direction, and the Y direction is the paper transport direction. The Z direction intersects with the Y direction and generally indicates the direction perpendicular to the surface of the transported paper. The +Y direction side is the front side of the device, and the -Y direction side is the rear side of the device. When viewed from the front side of the device, the left side is the +X direction and the right side is the -X direction. The +Z direction is the top of the device (including the upper part, top surface, etc.), and the -Z direction is the bottom of the device (including the lower part, bottom surface, etc.). The direction in which the paper P is fed (the +Y direction side) is called "downstream", and the opposite direction (the -Y direction side) is called "upstream".

■■■Scanner Overview■■■
A scanner 1 according to the present invention will be described below mainly with reference to FIGS.
The scanner 1 shown in FIG. 1 includes a device main body 2 that includes a reading unit 20 (FIG. 2) that reads an image on a sheet of paper P (medium).
The device main body 2 is comprised of a lower unit 3 and an upper unit 4. The upper unit 4 is attached to the lower unit 3 so as to be openable and closable with the downstream side in the paper transport direction as a pivot point, and is configured so that the upper unit 4 can be opened by rotating it toward the front side of the device to expose the paper transport path of the paper P, making it easy to clear paper jams of the paper P.

A medium loading section 11 for loading paper P is provided on the rear side (-Y axis direction side) of the device main body 2. A paper stack in which multiple sheets of paper P are stacked can be loaded on the medium loading section 11, and a booklet G (FIG. 3) in which multiple sheets of paper are arranged in a booklet shape can also be loaded as a manuscript. In FIG. 3, the open booklet G is set so that the bound spine is oriented along the width direction (X axis direction).
The medium placement unit 11 is detachably attached to the device body 2. Reference numeral 11a denotes a placement surface 11a on which the paper P is placed.

The medium loading section 11 is also provided with a pair of left and right edge guides 12, 12 having guide surfaces 13 that guide the side edges of the paper P in the width direction (X-axis direction) that intersects with the feeding direction (Y-axis direction).
The edge guides 12, 12 are provided so as to be slidable in the X-axis direction according to the size of the paper P. In this embodiment, the edge guides 12, 12 are configured such that one edge guide 12 (for example, the +X side) moves in the X direction by a known rack and pinion mechanism, and the other edge guide 12 (the -X side) moves in the opposing direction.
That is, in the medium loading section 11, the paper P is aligned in the center in the width direction, and a feed roller 14 described later is provided in the central area in the width direction, so that the paper is fed by a so-called center paper feeding method.

The media loading section 11 is equipped with a first auxiliary paper support 8 and a second auxiliary paper support 9. The first auxiliary paper support 8 and the second auxiliary paper support 9 can be stored inside the media loading section 11 as shown in FIG. 2, and can be pulled out from the media loading section 11 as shown in FIG. 1, making the length of the loading surface 11a adjustable.

As shown in FIG. 1, an operation panel 7 is provided on the front side of the upper unit 4 for performing various scanning settings and scanning execution operations, and for displaying the scanning setting contents and the like.
A feed port 6 that leads to the inside of the device main body 2 is provided at the top of the upper unit 4, and paper P placed on the media loading section 11 is sent from the feed port 6 toward a reading section 20 (Figure 2) provided inside the device main body 2.
Further, a paper discharge tray 5, which will be described later, is provided on the front side of the lower unit 3.

■■■About the paper transport path in the scanner■■■
Next, a paper transport path in the scanner 1 will be described with reference to Figures 2 and 3. Note that the dotted line in Figure 2 indicates the paper transport path.
In the scanner 1 shown in FIG. 2 , a paper sheet P serving as an original is fed from a medium loading section 11 toward a reading section 20 by a medium feeding section 10 .

In this embodiment, the medium feeding unit 10 includes a feed roller 14 that feeds the paper P, and a separation roller 15 that nips the paper P between the feed roller 14 and rotates in the opposite direction to the feed direction of the paper P (counterclockwise when viewed in plan in FIG. 3) to separate the paper P. The medium feeding unit 10 is configured to feed paper using a center paper feeding method, and the feed roller 14 and separation roller 15 are provided in the central region in the medium width direction (X-axis direction) that intersects with the medium transport direction (+Y direction).

When feeding paper P placed on the medium placement section 11 toward the reading section 20, the medium feeding section 10 is configured to be able to select between a "first feeding mode" in which a stack of multiple sheets of paper P is separated and fed, and a "second feeding mode" in which the stack of sheets is not separated and is fed together.

As a result, the scanner 1 can read paper that is separated and fed one sheet at a time (separate feeding), as well as stacks of paper that may cause feeding problems or jams if separated and fed one sheet at a time, such as booklets G (Figure 3) such as passports or bankbooks or stacks of documents, can be set directly on the media loading section 11 and fed without being placed in a sheet holder or case, and read by the reading section 20.
The operation of the medium feeding unit 10 is controlled by a control unit 19 provided inside the device main body 2. The specific operation of the medium feeding unit 10 when the medium feeding unit 10 feeds in the "first feeding mode" or the "second feeding mode" will be described in detail later.

Further, on the downstream side of the feed roller 14, a first transport roller pair 16 and a second transport roller pair 17 are provided to transport the paper P fed by the feed roller 14 (medium feeding section 10).
A reading unit 20 is provided between the first transport roller pair 16 and the second transport roller pair 17 .

In FIG. 2, paper P placed on the medium loading section 11 is picked up by a feed roller 14 rotatably mounted on the lower unit 3 and fed downstream (+Y direction). Specifically, the feed roller 14 feeds the paper P downstream by rotating while contacting the surface of the paper P facing the medium loading section 11. Therefore, when multiple sheets of paper P are set on the medium loading section 11 in the scanner 1, the paper P is fed downstream in order starting from the paper P on the loading surface 11a side.

The first transport roller pair 16 is provided upstream of the reading unit 20 and transports the paper P fed by the feed roller 14 toward the reading unit 20. The first transport roller pair 16 is configured to include a first drive roller 16a (drive roller) and a first driven roller 16b (driven roller).
Similar to the feed roller 14, the first transport roller pair 16 is also provided in the central region in the medium width direction.

The reading unit 20 includes a first reading unit 20a provided on the upper unit 4 side and a second reading unit 20b provided on the lower unit 3 side. In this embodiment, the first reading unit 20a and the second reading unit 20b are configured as a contact image sensor module (CISM) as an example.
The first reading unit 20a reads the front surface (the surface facing upward) of the paper P as the "first side", and the second reading unit 20b reads the back surface (the surface facing downward) as the "second side", which is the opposite side to the "first side".

After the image on at least one of the front and back sides of the paper P is read by the reading unit 20, the paper P is nipped by a second transport roller pair 17 located downstream of the reading unit 20 and discharged from a discharge port 18 provided on the front side of the lower unit 3. The second transport roller pair 17 is configured with a second drive roller 17a (drive roller) and a second driven roller 17b (driven roller) that rotates following the rotation of the second drive roller 17a.

In this embodiment, the feed roller 14 is rotationally driven by a first drive source 26 provided in the lower unit 3, as shown in Fig. 3. The separation roller 15, the first drive roller 16a, and the second drive roller 17a are rotationally driven by a second drive source 27 also shown in Fig. 3.
The first drive source 26 and the second drive source 27 are controlled by the control unit 19, and thus the drive of the feed roller 14, the separation roller 15, the first drive roller 16a, and the second drive roller 17a is controlled. In other words, the control unit 19 controls the feeding operation of the paper P.

The lower unit 3 is also provided with a paper output tray 5 that can be pulled out from the discharge port 18 toward the front of the device. The paper output tray 5 can be stored in the bottom of the lower unit 3 (FIG. 1) or pulled out to the front of the device (not shown). When the paper output tray 5 is pulled out, paper P discharged from the discharge port 18 can be stacked on the paper output tray 5.

2, a first detection unit 22 that detects the presence or absence of paper P placed on the medium placement unit 11 is provided downstream of the medium movement detection unit 21 in the medium feeding direction and upstream of the feed roller 14 within the paper placement area by the medium placement unit 11. Also, a second detection unit 23, a third detection unit 24, and a fourth detection unit 25 are provided, in this order, downstream of the feed roller 14, downstream of the first transport roller pair 16, and downstream of the second transport roller pair 17. The second detection unit 23 and the third detection unit 24 can detect the position of the paper P in the medium feeding direction.
The first detection portion 22, the second detection portion 23, the third detection portion 24, and the fourth detection portion 25 are provided in the central region in the width direction.

As the first detection unit 22, the second detection unit 23, the third detection unit 24, and the fourth detection unit 25, an optical sensor having a light emitting unit (not shown) that emits light and a light receiving unit (not shown) that receives the reflected light of the light emitted from the light emitting unit can be used. In addition to the optical sensor, it is also possible to use an ultrasonic sensor having a transmitter that emits ultrasonic waves and a receiver that is arranged opposite the transmitter across the transported paper. Also, a lever type sensor that detects the displacement of a mechanical lever that is moved by contact with the transported paper by optical or electrical contact can be used.

■■■Configuration for switching between the first feed mode and the second feed mode■■■
Below, we will explain how the medium feeding unit 10 switches between a "first feeding mode" in which it performs separation feeding, in which it separates and feeds a stack of paper P consisting of multiple sheets of paper, and a "second feeding mode" in which it performs non-separation feeding, in which it feeds the stack of paper together without separating them.

In the medium feeding section 10 according to this embodiment, the separation roller 15 is configured to be displaceable between a contact state in which it is in contact with the feed roller 14 and a separated state in which it is separated from the feed roller 14.

More specifically, as shown in FIG. 3 , the separation roller 15 is held by a holder 28 , and the holder 28 is pressed by a pressing member 29 , whereby the separation roller 15 is pressed against the feed roller 14 .
The separation roller 15 is configured to be displaceable along with the holder 28 in a direction toward and away from the feed roller 14, and by rotating a first eccentric cam 30 which rotates with power from a drive source (not shown) controlled by the control unit 19, the separation roller 15 can be switched between a contact state in which the separation roller 15 is in contact with the feed roller 14 (shown by a solid line in Figure 3) and a separated state in which the separation roller 15 is separated from the feed roller 14 (shown by a dotted line in Figure 3).
In FIG. 3, the pressing member 29 and the first eccentric cam 30 in the separated state are also shown by dotted lines.

When the medium feeding unit 10 feeds in the "first feeding mode" in which the paper is separated and fed, the separation roller 15 is placed in the contact state and driven to rotate in the reverse rotation direction (counterclockwise when viewed from above in FIG. 3) opposite to the forward rotation direction (clockwise when viewed from above in FIG. 3) in which the paper is fed in the reading direction (+Y direction) by the reading unit 20. As a result, the bottommost (lowest) paper of the multiple sheets of paper is separated and fed by the feeding roller 14.

The separation roller 15 is provided with a torque limiter (not shown), and when there is no medium between the separation roller 15 and the feed roller 14, or when there is only one medium, slippage occurs at the torque limiter, and the separation roller 15 rotates (clockwise direction in FIG. 3). When the second or subsequent medium enters between the separation roller 15 and the feed roller 14, slippage occurs between the media, and the separation roller 15 rotates in the opposite direction (counterclockwise direction in FIG. 3) due to the rotational torque it receives from the second drive source 27. This prevents multiple media from being fed.

On the other hand, when the medium feeding unit 10 feeds in the "second feeding mode" in which the medium is fed without being separated, the separation roller 15 is placed in the separated state. By separating the separation roller 15 from the feed roller 14, the paper separation ability of the separation roller 15 can be reduced or eliminated.
As a result, the stack of sheets (booklets G in FIG. 3) placed on the medium placement unit 11 can be fed without being separated, that is, in a non-separated state.
Note that separation is not performed by the separation roller 15 when the separation roller 15 in the separated state is separated to a position where it does not contact the top surface of the paper stack (booklet G) placed on the medium loading section 11. The separation roller 15 in the separated state may be in contact with the top surface of the paper stack (booklet G) placed on the medium loading section 11, but in that case, it is preferable to stop the rotation of the separation roller 15 to allow it to rotate freely, or to rotate the separation roller 15 in the forward rotation direction (clockwise when viewed in plan in FIG. 3).

As described above, by switching the separation roller 15 between the contact state and the separated state, it is possible to easily switch between the "first feeding mode" and the "second feeding mode" in the medium feeding unit 10.

■■■First and second conveyor roller pairs■■■
As explained in the problem that the invention aims to solve, since the booklet G shown in Figure 3 has a thickness, the booklet G fed by the medium feeding section 10 may not be able to enter between the rollers of the first conveying roller pair 16 or the second conveying roller pair 17 downstream, resulting in a non-feed state.

To prevent non-feeding of the booklet G in the first transport roller pair 16 or the second transport roller pair 17, when the medium feeding unit 10 in the scanner 1 feeds in the "second feeding mode", the first driven roller 16b of the first transport roller pair 16 and the second driven roller 17b of the second transport roller pair 17 are driven in the rotational direction in which each transport roller pair transports the paper.

That is, when the medium feeding unit 10 performs feeding in the "second feeding mode", the first driven roller 16b and the second driven roller 17b rotate clockwise when viewed in plan in FIG.
In this embodiment, the first driven roller 16b and the second driven roller 17b are configured to receive power from the second drive source 27 and have their drive controlled by the control unit 19. Of course, they may be configured to receive power from the first drive source 26, or another drive source may be provided.
A switching means (not shown) is provided for switching between a state in which power is transmitted from the first driving source 26 to the first driven roller 16b and the second driven roller 17b and a state in which the transmission of the power is cut off. By controlling the switching means by the control unit 19, it is possible to switch between a state in which the first driven roller 16b and the second driven roller 17b are driven to rotate and a state in which the first driven roller 16b and the second driven roller 17b are driven to rotate in response to the rotation of the first driving roller 16a and the second driving roller 17a.

In this way, when the medium feeding unit 10 feeds in the "second feeding mode," the first driven roller 16b and the second driven roller 17b are also rotated in the direction of transporting the paper, making it easier for the thick booklet G to enter between the rollers of the first transport roller pair 16 and the second transport roller pair 17, thereby suppressing the occurrence of non-feeds in the first transport roller pair 16 and the second transport roller pair 17 and enabling proper transport of the booklet G.

■■■Other configurations in the second feeding mode■■■
When the "second feeding mode" is executed, the following configuration can be adopted.
That is, when the second detection unit 23 (Figures 2 and 3), which is provided as a "media detection unit" that detects paper between the medium feeding unit 10 and the first drive roller 16a, which is the "drive roller" closest to the medium feeding unit 10, detects the passage of the leading edge of the document (booklet G) fed by the medium feeding unit 10 in the "second feeding mode", it puts the separation roller 15 into the contact state (the state of the separation roller 15 shown by the solid line in Figure 3) and drives it to rotate in the positive rotation direction (clockwise in Figure 3).

After the booklet G fed by the feeding roller 14 has been fed to a certain extent, the separation roller 15 is brought into contact with the booklet G and driven to rotate in the forward rotation direction, so that the medium feeding unit 10 can apply a conveying force to the booklet G. This allows the booklet G to be conveyed efficiently.
The timing for putting the separation roller 15 into the contact state and driving it to rotate in the forward rotation direction is not limited to the timing when the second detection unit 23 detects the booklet G. For example, the separation roller 15 may be switched from the separated state to the contact state and driven to rotate in the forward rotation direction after a predetermined time has elapsed since the second detection unit 23 detected the booklet G, or after a predetermined amount of conveyance has been carried out.

■■■About the reading unit■■■
Next, the configuration of the reading unit 20 will be described.
3 includes a first reading unit 20a located on the upper side and a second reading unit 20b located on the lower side across the paper transport path. In other words, the distance between the reading surface of the first reading unit 20a and the reading surface of the second reading unit 20b is the path height of the paper transport path.

Usually, the distance between the reading surface of the first reading unit 20a and the reading surface of the second reading unit 20b is set to a distance through which thin paper can pass, and the first reading unit 20a and the second reading unit 20b are pressed in a direction approaching each other, so that the reading surface of each reading unit is firmly in contact with the paper P (original).
In addition, in Figure 3, symbol 31 is a first pressing member 31 such as a coil spring that presses the first reading unit 20a toward the second reading unit 20b, and symbol 32 is a second pressing member 32 such as a coil spring that presses the second reading unit 20b toward the first reading unit 20a.

Further, either the first reading unit 20a or the second reading unit 20b is configured to be displaceable so as to move toward or away from the other, and the distance between the first reading unit 20a and the second reading unit 20b is configured to be changeable.
In this embodiment, the first reading unit 20a is provided with a displacement mechanism, which is configured to displace the first reading unit 20a between an advanced position shown by a solid line in Fig. 3 and a retracted position shown by a dotted line in Fig. 3. The displacement mechanism includes a second eccentric cam 33 that is rotated by a driving source (not shown). The driving source is controlled by the control unit 19, which also controls the rotation of the second eccentric cam 33, thereby making it possible to adjust the distance between the first reading unit 20a and the second reading unit 20b.

Here, the control unit 19 executes control to make the distance between the first reading unit 20a and the second reading unit 20b wider when the medium feeding unit 10 executes the "second feeding mode" than the distance when the medium feeding unit 10 executes the "first feeding mode".
That is, when the booklet bundle G is fed in the "second feeding mode", the distance between the first reading unit 20a and the second reading unit 20b is widened. This reduces the risk of the booklet bundle G, which is thicker than the paper P that is transported one sheet at a time, getting caught between the first reading unit 20a and the second reading unit 20b and causing a jam.

[Second embodiment]
In this embodiment, referring to Figure 4, another example of a configuration for suppressing non-feed of the booklet G in the first conveying roller pair 16 or the second conveying roller pair 17 when the medium feeding unit 10 feeds in the "second feeding mode" is described.
FIG. 4 is a schematic cross-sectional side view of the scanner according to the second embodiment.
In the following embodiments, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

Non-feed of the booklet G in the first transport roller pair 16 or the second transport roller pair 17 can also be suppressed by the following configuration.
That is, for the first transport roller pair 16, when the medium feeding unit 10 feeds in the "second feeding mode", the contact load applied by the first driven roller 16b to the first driving roller 16a is set to be smaller than the contact load when the "first feeding mode" is executed. Also, for the second transport roller pair 17, when the medium feeding unit 10 feeds in the "second feeding mode", the contact load applied by the second driven roller 17b to the second driving roller 17a is set to be smaller than the contact load when the "first feeding mode" is executed.

More specifically, the scanner 1 is equipped with a load applying means 40 that can change the contact load that the first driven roller 16b applies to the first drive roller 16a in the first transport roller pair 16, and the contact load that the second driven roller 17b applies to the second drive roller 17a in the second transport roller pair 17.

The load applying means 40 includes a spring support portion 41 that is displaceable along the direction (the direction of arrow A in FIG. 4) in which the first driven roller 16b and the second driven roller 17b apply the contact load to the corresponding driving rollers (the first driving roller 16a and the second driving roller 17a), and a pressure spring 42 and a pressure spring 43 that are provided between the spring support portion 41 and the first driven roller 16b, and between the spring support portion 41 and the second driven roller 17b, and press the first driven roller 16b and the second driven roller 17b.

The contact load of each of the first driven roller 16 b and the second driven roller 17 b can be adjusted by displacing the spring support portion 41 .
When the spring support part 41 is displaced in the direction of arrow A, that is, when the spring support part 41 is brought closer to the first driven roller 16b and the second driven roller 17b, the contact load increases, and when the spring support part 41 is displaced in the opposite direction to the direction of arrow A, that is, when the spring support part 41 is moved away from the first driven roller 16b and the second driven roller 17b, the contact load decreases.

In this embodiment, the spring support portion 41 is configured to be displaced by the rotation of a third eccentric cam 44 that receives power from a driving source (not shown). The driving source is controlled by the control unit 19, whereby the rotation of the third eccentric cam 44 is controlled and the contact load can be adjusted.
In this embodiment, both the compression spring 42 for the first driven roller 16b and the compression spring 43 for the second driven roller 17b are supported by a common spring support portion 41, but it is also possible to configure the compression spring 42 for the first driven roller 16b and the compression spring 43 for the second driven roller 17b to be each supported by an individual spring support portion.
The load applying means 40 configured as described above can easily adjust the contact load that the first driven roller 16b and the second driven roller 17b apply to the corresponding drive rollers, the first drive roller 16a and the second drive roller 17a.

When the medium feeding unit 10 feeds in the "second feeding mode", the contact load that the first driven roller 16b and the second driven roller 17b apply to the corresponding first drive roller 16a and the second drive roller 17a is smaller than the contact load when the "first feeding mode" is executed, so that the booklet G can easily enter between the rollers of the first transport roller pair 16 and the second transport roller pair 17. This reduces the risk of the booklet G not being fed in the first transport roller pair 16 and the second transport roller pair 17, and allows the booklet G to be properly transported.

In this embodiment, the first driven roller 16b and the second driven roller 17b are moved in a direction away from the first driving roller 16a and the second driving roller 17a by a displacement means (not shown), and are configured to be separable from the first driving roller 16a and the second driving roller 17a. When the medium feeding unit 10 performs feeding in the "second feeding mode", the first driven roller 16b and the second driven roller 17b can be separated from the first driving roller 16a and the second driving roller 17a.
In other words, when the medium feeding unit 10 feeds in the "second feeding mode", the contact load is set to zero. This makes it possible to further suppress the occurrence of non-feeding of the booklet G in the first transport roller pair 16 and the second transport roller pair 17.
The displacement means is controlled by the control section 19, and the separation of the first driven roller 16b and the second driven roller 17b from the first driving roller 16a and the second driving roller 17a is controlled.

[Third embodiment]
The scanner 1 can be provided with a page turning mechanism 50 that automatically turns the pages of the booklet G being read. In this embodiment, the page turning mechanism 50 will be described with reference to Figs. 5 and 6.
5 and 6 are diagrams for explaining the page turning operation by the page turning mechanism.

5 and 6 is provided on the first driven roller 16b that constitutes the first transport roller pair 16. In other words, the scanner 1 includes the first driven roller 16b having the page turning mechanism 50.
More specifically, the page-turning mechanism 50 includes a holding portion 51 and a tip portion 52 movably attached to the tip of the holding portion 51, which are provided on the first driven roller 16b.

The first transport roller pair 16 and the second transport roller pair 17 are configured to be rotatable in both a forward rotation direction (for example, the rotation direction indicated by the arrow in the top diagram of FIG. 5) for transporting the paper in the reading direction (+Y direction) by the reading unit 20, and a reverse rotation direction (for example, the rotation direction indicated by the arrow in the second diagram from the top of FIG. 5) for transporting the paper in the opposite direction to the reading direction (-Y direction). In addition, the first driven roller 16b of the first transport roller pair 16 is configured to be driven to rotate at least in the reverse rotation direction by receiving power from a drive source (not shown).
The page-turning mechanism 50 is configured to turn the topmost medium of the booklet G by the first driven roller 16b that is driven to rotate in the reverse direction.

Hereinafter, the page turning operation by the page turning mechanism 50 will be described with reference to FIGS.
5 shows a state in which reading of the first page P1 of the booklet G has been completed. When reading is performed by the reading unit 20, the first transport roller pair 16 and the second transport roller pair 17 are rotating in the forward rotation direction.

After the reading of the first page of the spread is completed, as shown in the second diagram from the top in FIG. 5, the first transport roller pair 16 and the second transport roller pair 17 are rotated in the reverse rotation direction, and the leading edge of the booklet G in the reading direction is nipped by the first transport roller pair 16.

When the leading edge of the booklet G in the reading direction is nipped by the first transport roller pair 16, the first drive roller 16a stops, and only the first driven roller 16b is driven to rotate in the reverse rotation direction.
Then, as shown in the second drawing from the bottom in FIG. 5, the first driven roller 16b picks up the top page.
When the first driven roller 16b is subsequently driven to rotate in the reverse direction, the leading edge of the picked up page is caught and held by the holding portion 51 and the leading edge portion 52, as shown in the bottom diagram of FIG.

When the first driven roller 16b is rotated in the reverse direction by a predetermined amount, the driving of the first driven roller 16b is stopped, and the leading end 52 is displaced so as to bend upward, as shown in the top diagram of Fig. 6. As a result, the leading end of the page held by the holding portion 51 and the leading end 52 is released and turned over, and the second page P2 of the spread is opened.
The tip portion 52 operates by receiving power from a power source (not shown).

After the pages of the booklet G are turned and the second page P2 of the spread is opened, the first transport roller pair 16 and the second transport roller pair 17 are rotated in the forward rotation direction to read the second page P2 of the spread, as shown in the second drawing from the top to the second drawing from the bottom of FIG. 6.

After completing the reading of the second page P2 of the spread (the second from the bottom in Figure 6), if the next page (the third page of the spread) is to be read, as shown in the bottommost figure in Figure 6, the first transport roller pair 16 and the second transport roller pair 17 are rotated again in the reverse rotation direction to feed the leading edge of the booklet G in the reading direction to a position where it is nipped by the first transport roller pair 16, and the leading edge 52 is returned to the direction connected to the holding portion 51, and the operations from the second from the bottom in Figure 5 onwards are repeated.
Incidentally, the timing for returning the bent tip portion 52 in the top diagram of Figure 6 to its original state may be before the start of the page turning operation in which only the first driven roller 16b is driven to rotate in the reverse rotation direction (the operation in the second diagram from the bottom in Figure 5), and is not limited to immediately before the page turning operation.

As described above, the scanner 1 is equipped with the first transport roller pair 16 having the page-turning mechanism 50, so that the pages of the booklet G can be automatically turned while reading. This makes it easy to read multiple pages of the booklet G in succession.

[Fourth embodiment]
In this embodiment, another example of the configuration for switching between the "first feeding mode" and the "second feeding mode" of the medium feeding unit 10 will be described with reference to Figs.
Fig. 7 is an external perspective view of a scanner provided with an operating unit for switching between the "first feeding mode" and the "second feeding mode" of the medium feeding unit. Fig. 8 is a perspective view showing the state of the power transmission mechanism in the "first feeding mode" of the medium feeding unit. Fig. 9 is a perspective view showing the state of the medium feeding unit in the "second feeding mode". Fig. 10 is an enlarged view of a main part of the power transmission mechanism, and is a diagram for explaining the displacement of gears when switching between the "first feeding mode" and the "second feeding mode" of the medium feeding unit.

In this embodiment, switching between a "first feeding mode" in which the medium feeding unit 10 separates and feeds the paper, and a "second feeding mode" in which the medium feeding unit 10 does not separate and feed the paper, is performed by switching between a connected state (Figure 8) in which the transmission of power to the separation roller 15 is connected, and a released state (Figure 9) in which the transmission of power to the separation roller 15 is released.
In other words, it is equipped with a power transmission mechanism 60 that transmits power from the second drive source 27 to the separation roller 15, and the power transmission mechanism 60 has a second gear train 62 as a "gear train" composed of a plurality of meshing gears, and when the medium feeding unit 10 performs feeding in the "second feeding mode", some of the meshing of the plurality of gears that constitute the second gear train 62 is released.

The power transmission mechanism 60 will now be described with reference to FIG.
The power transmission mechanism 60 includes a first gear train 61 having a gear that meshes with a rotation shaft (not shown) of the separation roller 15, a second gear train 62 provided on the -X direction side inside the device main body 2 (Figure 1), and a shaft portion 63 connecting the first gear train 61 and the second gear train 62.

The second gear train 62 is configured to include a gear 64 , a gear 65 that meshes with the gear 64 , and a group of gears 66 that includes a gear that meshes with the gear 65 and a gear connected to the shaft portion 63 .
8, the gear 64 is connected to a rotation shaft (not shown) of the first transport roller pair 16, and is configured to receive power from the second drive source 27 via the first transport roller pair 16 (driven by the power of the second drive source 27). The power received by the gear 64 of the second gear train 62 is transmitted to the separation roller 15 via the shaft portion 63 and the first gear train 61.

7, the upper unit 4 of the scanner 1 is provided with an operation unit 67 for switching between the "first feeding mode" and the "second feeding mode" of the medium feeding unit 10. Reference numeral 67a denotes a knob portion 67a for operation.
The operating unit 67 is configured to slide back and forth in the X-axis direction relative to the upper unit 4, and as shown in Figures 8 and 9, is connected at a connecting portion 68 to a gear 65 of the second gear train 62 that constitutes a power transmission mechanism 60 that transmits power from the second drive source 27 to the separation roller 15.
The gear 65 connected to the operation unit 67 is configured to be shiftable in the sliding direction of the operation unit 67. This makes it possible to slide the operation unit 67 in the X-axis direction to switch between the connected state (FIG. 8) in which the gear 65 and the gear 64, and the gear 65 and the gear group 66 are engaged with each other, and a released state (FIG. 9) in which the gear 65 and the gear 64, and the gear 65 and the gear group 66 are disengaged from each other.

In this embodiment, when the knob portion 67a of the operating unit 67 is slid toward the +X direction, the gear 65 is positioned at the position shown by the solid lines in Figures 8 and 10, and the gear 65 and the gear 64, and the gear 65 and the gear group 66 are in a meshed connection state.
In the connected state, the power of the second drive source 27 is transmitted to the separation roller 15, and the separation roller 15 separates the paper. In other words, the medium feeding unit 10 can be set to the "first feeding mode".
In addition, in FIG. 10, the operation unit 67 and the connection unit 68 are omitted.

When the operating unit 67 is slid in the -X direction, the gear 65 is positioned at the position shown by the two-dot chain line in Figures 9 and 10, and the gear 65 is released from meshing with the gear 64, and the gear 65 is released from meshing with the gear group 66, resulting in a release state. In this release state, no power is transmitted from the gear 64 to the gear group 66, so the separation roller 15 does not rotate. In other words, the separation roller 15 does not separate the paper. Therefore, the medium feeding unit 10 can be set to the "second feeding mode."

With the above configuration, the medium feeding unit 10 can easily switch between feeding in the "first feeding mode" and feeding in the "second feeding mode".
As described above, in addition to manually displacing the gear 65 in the X-axis direction using the operating unit 67, it is also possible to automatically displace the gear 65 in the X-axis direction using an actuator such as a solenoid.

In addition, the scanner 1 may be provided with both a configuration for switching the medium feeding section 10 between the "first feeding mode" and the "second feeding mode", which is a configuration for separating the separation roller 15 from the feeding roller 14 as described in the first embodiment, and a configuration for releasing the meshing of the gears that constitute the second gear train 62 of the power transmission mechanism 60 as described in this embodiment.
After separating the separation roller 15 from the feed roller 14, the gears constituting the second gear train 62 can be disengaged to stop the rotation of the separation roller 15 in the separation direction, thereby more reliably achieving a non-separation state in which separation is not performed by the separation roller 15.

The present invention is not limited to the embodiments described above, and various modifications are possible within the scope of the invention described in the claims, and it goes without saying that these modifications are also included within the scope of the present invention.

1...scanner (image reading device), 2...device main body, 3...lower unit,
4: upper unit, 5: output tray, 6: feed port, 7: operation panel,
8...first auxiliary paper support, 9...second auxiliary paper support,
10...medium feeding section, 11...medium placement section, 12...edge guide,
13: guide surface; 14: feed roller; 15: separation roller;
16...first conveying roller pair, 16a...first driving roller (driving roller),
16b: first driven roller (driven roller); 17: second conveying roller pair;
17a...second driving roller (driving roller),
17b... second driven roller (driven roller), 18... discharge port,
19: control unit, 20: reading unit, 20a: first reading unit, 20b: second reading unit,
22: first detection unit, 23: second detection unit, 24: third detection unit, 25: fourth detection unit,
26: first driving source, 27: second driving source, 28: holder, 29: pressing member,
30: first eccentric cam; 31: first pressing member; 32: second pressing member;
33: second eccentric cam; 40: load applying means; 41: spring support portion;
42: Pressure spring, 43: Pressure spring, 44: Third eccentric cam,
50: page turning mechanism, 51: holding portion, 52: tip portion,
60: power transmission mechanism, 61: first wheel train, 62: second wheel train, 63: shaft portion,
64 ... gear, 65 ... gear, 66 ... gear group, 67 ... operation portion, 68 ... connection portion,
P...Paper (medium), G...Booklet (medium bundle)

Claims (3)

A placement section for placing paper and booklets ;
a feed roller that feeds the paper and the booklet from the placement section;
a separation roller for nipping the paper between the feeding roller and the separation roller to separate the paper ;
a first reading unit that reads images of the fed paper and booklet ;
a second reading unit disposed opposite the first reading unit and configured to read images of the fed paper and booklet;
a first direction is a direction from the first reading unit and the second reading unit toward a discharge port, and a second direction is a direction opposite to the first direction, the first direction being a roller pair located in the second direction relative to the first reading unit and the second reading unit , the first transport roller pair transporting the paper and the booklet ;
a second transport roller pair that is located in the first direction relative to the first reading unit and the second reading unit and transports the paper and the booklet ;
A first driving source that drives the feed roller;
a second drive source that drives the separation roller, the first conveying roller pair, and the second conveying roller pair;
a power transmission mechanism having a gear train formed of a plurality of meshing gears, the power transmission mechanism being switchable between a state in which power from the second drive source is transmitted to the separation roller and a state in which power from the second drive source is not transmitted to the separation roller;
A control unit,
Both of the two rollers constituting the first transport roller pair are drivable,
Both of the two rollers constituting the second transport roller pair are drivable,
when transporting the booklet , the control unit drives both of the two rollers constituting the first transport roller pair and both of the two rollers constituting the second transport roller pair to rotate in a first rotation direction so as to transport the booklet in the first direction;
Furthermore, the control unit
A first feeding mode in which the paper is separated and fed, and a second feeding mode in which the booklet is fed without being separated, are selectable;
In the first feeding mode and the second feeding mode, the feeding roller is rotated in the first rotation direction so as to transport the paper and the booklet in the first direction;
In the first feeding mode, while the power transmission mechanism transmits the power of the second drive source to the separation roller, the separation roller is rotationally driven in a second rotation direction so as to transport the paper in the second direction;
the power transmission mechanism does not transmit the power of the second driving source to the separation roller in the second feeding mode,
a distance between the first reading unit and the second reading unit is changeable, and the distance between the first reading unit and the second reading unit in the second feeding mode is wider than the distance between the first reading unit and the second reading unit in the first feeding mode;
1. An image reading apparatus comprising: 2. The image reading apparatus according to claim 1,
a first pressing member that presses the first reading unit toward the second reading unit;
1. An image reading apparatus comprising: 2. The image reading apparatus according to claim 1,
a second pressing member that presses the second reading unit toward the first reading unit;
1. An image reading apparatus comprising:

Images