Image reading device

Abstract

To solve the following problem: in a structure in which a transmission gear provided in an upper unit and a transmission gear provided in a lower unit come into mesh with and become disengaged from each other, backlash between the transmission gear provided in the upper unit and the transmission gear provided in the lower unit tends to vary.SOLUTION: An image reading apparatus includes: a first unit; a second unit which is rotatable with respect to the first unit and opens / closes with respect to the first unit when rotated; a motor disposed in the first unit or the second unit; and a power transmission mechanism which transmits motive power from the first unit to the second unit, or from the second unit to the first unit. The power transmission mechanism includes a first gear having the same axial center of rotation as that of the second unit, and a second gear which is provided in the second unit and is in mesh with the first gear.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present invention relates to an image reading device that reads an image on a medium. [Background technology]

[0002] One example of an image reading device is a sheet-fed scanner. Hereinafter, the term "scanner" will refer to a sheet-fed scanner. As shown in Patent Document 1, some scanners have a lower unit and an upper unit that can be opened and closed relative to the lower unit, and a document transport path is exposed when the upper unit is opened.

[0003] A separation roller is provided in the upper unit, and power is transmitted to the separation roller from a motor provided in the lower unit. When the upper unit is closed, a transmission gear provided in the upper unit and a transmission gear provided in the lower unit mesh, transmitting power from the motor to the separation roller. When the upper unit is open, the transmission gear provided in the upper unit and the transmission gear provided in the lower unit separate from each other. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2017-224994 Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-described configuration in which the transmission gear provided in the upper unit and the transmission gear provided in the lower unit mesh and separate, the backlash between the transmission gear provided in the upper unit and the transmission gear provided in the lower unit is likely to vary. If the backlash between the two meshing transmission gears is smaller than the appropriate value, it may result in an increased load on the motor and a shortened gear life. Conversely, if the backlash between the two meshing transmission gears is larger than the appropriate value, it may result in a decrease in the rotation accuracy of the roller and significant noise and vibration may be generated at the meshing portion of the two transmission gears. [Means for solving the problem]

[0006] In order to solve the above problem, the image reading device of the present invention comprises a first unit, a second unit that is rotatable relative to the first unit and opens and closes relative to the first unit by rotating, a motor provided in the first unit or the second unit, and a power transmission mechanism that transmits the power of the motor from the first unit to the second unit or from the second unit to the first unit, wherein when the second unit is closed relative to the first unit, a document transport path for transporting documents is formed, and when the second unit is opened relative to the first unit, the document transport path is opened, and the power transmission mechanism is characterized in that it has a first gear having a common rotation axis center with the rotation axis center of the second unit, and a second gear provided in the second unit that meshes with the first gear. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a perspective view of the scanner when viewed from the front, with the device body in a normal reading position. [Figure 2] FIG. 2 is a perspective view of the scanner when viewed from the rear, with the device main body in the normal reading position. [Figure 3] FIG. 10 is a perspective view of the scanner seen from the front with the device main body in the normal reading position and the third unit open. [Figure 4]FIG. 10 is a perspective view of the scanner viewed from above with the main body in the normal reading position and the second unit open. [Figure 5] 1 is a cross-sectional view of the document transport path of the scanner when the device body is in the normal reading position, viewed from the width direction. [Figure 6] 10 is a cross-sectional view of the document transport path of the scanner when the device main body is in a booklet reading position, viewed from the width direction. [Figure 7] FIG. [Figure 8] FIG. 10 is a cross-sectional view showing a structure for locking the second unit. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] FIG. [Figure 12] FIG. 2 is a perspective view showing a configuration for transmitting power from a conveyance motor to each roller. [Figure 13] FIG. 4 is a side view showing a configuration for transmitting power from a conveyance motor to each roller. [Figure 14] FIG. 4 is a side view showing a configuration for transmitting power from a conveyance motor to each roller. [Figure 15] FIG. 4 is a side view showing a configuration for transmitting power from a conveyance motor to each roller. DETAILED DESCRIPTION OF THE INVENTION

[0008] The present invention will be briefly described below. An image reading device according to a first aspect comprises a first unit, a second unit that is rotatable relative to the first unit and opens and closes relative to the first unit by rotating, a motor provided in the first unit or the second unit, and a power transmission mechanism that transmits the power of the motor from the first unit to the second unit or from the second unit to the first unit, wherein when the second unit is closed relative to the first unit, a document transport path for transporting documents is formed, and when the second unit is opened relative to the first unit, the document transport path is opened, and the power transmission mechanism comprises a first gear having a common rotation axis center with the rotation axis center of the second unit, and a second gear provided in the second unit that meshes with the first gear.

[0009] According to this aspect, the power transmission mechanism that transmits the power of the motor from the first unit to the second unit or from the second unit to the first unit includes a first gear having a common rotation axis center with the rotation axis center of the second unit, and a second gear that is provided in the second unit and meshes with the first gear, so that even when the second unit is opened, the second gear performs planetary motion around the first gear, but the meshing between the second gear and the first gear does not disengage. With this configuration, it is possible to appropriately maintain backlash in the meshing between the first gear and the second gear, and to suppress problems associated with fluctuations in the backlash.

[0010] A second aspect is the first aspect, wherein the document feeder includes a first reading unit provided in the first unit and configured to read an image of a document fed through the document feed path, a second reading unit provided in the second unit and configured to read an image of a document fed through the document feed path, a first transport roller pair located upstream of the document feed path relative to the first reading unit and the second reading unit, and a second transport roller pair located downstream of the document feed path relative to the first reading unit and the second reading unit, The reading conveying path includes a first lower roller that contacts the underside of the document being transported through the reading conveying path, and a first upper roller in the second unit that contacts the upper side of the document being transported through the reading conveying path, the second conveying roller pair includes a second lower roller that contacts the underside of the document in the first unit, and a second upper roller that contacts the upper side of the document in the second unit, and the motor drives the first lower roller, the first upper roller, the second lower roller, and the second upper roller via the power transmission mechanism.

[0011] According to this aspect, the first lower roller, the first upper roller, the second lower roller, and the second upper roller are all driven by the motor, so that thick originals can be transported reliably.

[0012] A third aspect is characterized in that, in the second aspect, the first upper roller is movable toward and away from the first lower roller and is pressed toward the first lower roller, the second upper roller is movable toward and away from the second lower roller and is pressed toward the second lower roller, and the direction of rotation of the first gear when transporting a document by the first transport roller pair and the second transport roller pair is a direction in which the first gear applies a force to the second gear in the direction of opening the second unit.

[0013] Since the first upper roller is movable toward and away from the first lower roller and is pressed toward the first lower roller, and the second upper roller is movable toward and away from the second lower roller and is pressed toward the second lower roller, the second unit, which includes the first upper roller and the second upper roller, receives a force in the opening direction from the first unit in the closed state. Hereinafter, this force will be referred to as a first force. According to this aspect, when the document is transported by the first transport roller pair and the second transport roller pair, the rotation direction of the first gear is such that the first gear applies a force to the second gear in a direction to open the second unit. Hereinafter, this force will be referred to as a second force. Since the first force and the second force both act in the direction that opens the second unit, the amount of backlash between the first gear and the second gear is stabilized compared to a configuration in which the first force and the second force act on the second unit in opposite directions.

[0014] A fourth aspect is characterized in that, in the second or third aspect, a third unit is provided that is rotatable relative to the first unit and the second unit and opens and closes relative to the first unit and the second unit by rotating, the center of the rotation axis of the third unit is common with the center of the rotation axis of the second unit, and the power transmission mechanism has a gear provided on the third unit and a third gear that meshes with the first gear.

[0015] According to this aspect, the power transmission mechanism includes a third gear provided in the third unit and meshing with the first gear, so that even when the third unit is opened, the third gear performs planetary motion around the first gear but the meshing between the third gear and the first gear does not disengage. With this configuration, it is possible to appropriately maintain backlash in the meshing between the first gear and the third gear, and to suppress problems associated with fluctuations in the backlash.

[0016] A fifth aspect of the present invention is directed to the fourth aspect, in which an original transport path between the first transport roller pair and the second transport roller pair is a reading transport path, an original transport path downstream of the reading transport path, a reversing transport path when a read original is reversed and discharged facing upward, an original transport path downstream of the reading transport path, a non-reversing transport path when a read original is discharged without being reversed, a transport path switching unit that switches the original transport path connected to the reading transport path to either the reversing transport path or the non-reversing transport path, a third transport roller pair that is a roller pair provided in the reversing transport path and located downstream of the second transport roller pair, and a roller pair provided in the reversing transport path, and a fourth transport roller pair located downstream of the third transport roller pair, the reverse transport path being formed between the second unit and the third unit, the third transport roller pair comprising a third drive roller that contacts the bottom surface of the document in the third unit and is driven by the motor, and a third driven roller that contacts the top surface of the document in the second unit and is driven to rotate in contact with the document, and the fourth transport roller pair comprising a fourth drive roller that contacts the bottom surface of the document in the third unit and is driven by the motor, and a fourth driven roller that contacts the top surface of the document in the second unit and is driven to rotate in contact with the document.

[0017] According to this aspect, the image reading device can switch between the reversing conveying path and the non-reversing conveying path, and therefore, by using the non-reversing conveying path, it is possible to satisfactorily convey an original that is difficult to bend.

[0018] A sixth aspect is characterized in that, in the fifth aspect, the third driven roller is movable toward and away from the third drive roller and is pressed toward the third drive roller, the fourth driven roller is movable toward and away from the fourth drive roller and is pressed toward the fourth drive roller, and the direction of rotation of the first gear when transporting a document by the third transport roller pair and the fourth transport roller pair is the direction in which the first gear applies a force to the third gear in the direction of opening the third unit.

[0019] The third driven roller is movable toward and away from the third drive roller and is pressed toward the third drive roller, and the fourth driven roller is movable toward and away from the fourth drive roller and is pressed toward the fourth drive roller, so that the third unit receives a force from the second unit in the opening direction when in the closed state. Hereinafter, this force will be referred to as a third force. According to this aspect, when the document is transported by the third transport roller pair and the fourth transport roller pair, the rotation direction of the first gear is such that the first gear applies a force to the third gear in a direction to open the third unit. Hereinafter, this force will be referred to as a fourth force. Since the third force and the fourth force both act in the direction that opens the third unit, the amount of backlash between the first gear and the third gear is stabilized compared to a configuration in which the third force and the fourth force act on the third unit in opposite directions.

[0020] In the seventh aspect, in the fifth or sixth aspect, the gears constituting the power transmission mechanism, which are provided in the first unit, are arranged along the reading conveying path on the side of the first frame that constitutes the base of the first unit, and the gears constituting the power transmission mechanism, which are provided in the second unit, are arranged along the reading conveying path on the side of the second frame that constitutes the base of the second unit, thereby preventing the device from becoming larger.

[0021] The eighth aspect is characterized in that, in the second aspect, the first upper roller is movable toward and away from the first lower roller and is pressed toward the first lower roller, the second upper roller is movable toward and away from the second lower roller and is pressed toward the second lower roller, and the power of the motor is transmitted to the first upper roller and the second upper roller by a universal joint.

[0022] According to this aspect, the power of the motor is transmitted to the movable first upper roller and the movable second upper roller by a universal joint, so that the power of the motor can be appropriately transmitted to the movable first upper roller and the movable second upper roller.

[0023] 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 first side and the opposite second side of a document will be taken as an example. The scanner 1 is a so-called sheet-fed type scanner that reads a document while moving it relative to a reading unit described below. In this specification, the document includes not only a sheet-shaped document but also a card-shaped document and a booklet-shaped document.

[0024] In the XYZ coordinate system shown in each figure, the X axis direction is the width direction of the device and also the width direction of the original, the Y axis direction is the depth direction of the device, and the Z axis direction is the vertical direction. In this embodiment, the +Y direction is the direction from the rear to the front of the device, and the -Y direction is the direction from the front to the rear of the device. Also, the left direction as viewed from the front of the device is the +X direction, and the right direction is the -X direction. In the following description, the direction in which the document is transported may be referred to as "downstream," and the opposite direction may be referred to as "upstream."

[0025] 1 and 2, a scanner 1 includes a device main body 2 and a main body support part 6 that supports the device main body 2 so that it can rotate. The device main body 2 is configured to include a first unit 3, a second unit 4, and a third unit 5.

[0026] The second unit 4 and the third unit 5 are provided so as to be rotatable about a frame rotation axis 64a (see FIG. 3). The frame rotation axis 64a is a rotation axis that forms the rotation axis center parallel to the X-axis direction. The second unit 4 and the third unit 5 can rotate integrally around the frame rotation axis 64a relative to the first unit 3 (see FIG. 4). By rotating the second unit 4 and the third unit 5 relative to the first unit 3, it is possible to expose a portion of the document transport path as shown in FIG. 4. In particular, it is possible to expose the document feed path R1 and the reading transport path R2, which will be described later.

[0027] The third unit 5 can rotate about a frame rotation axis 64a relative to the first unit 3 and the second unit 4 (see FIG. 3). By rotating the third unit 5 relative to the first unit 3 and the second unit 4, a part of the document transport path can be exposed as shown in FIG. 3. In particular, the reverse transport path R3, which will be described later, can be exposed.

[0028] The device main body 2 is rotatable around a main body rotation axis 6c (see FIGS. 5 and 6) relative to the main body support part 6, and in this embodiment, the device main body 2 can hold two postures by rotating. The two postures of the device main body 2 are shown in FIGS. 5 and 6, and hereinafter the posture in FIG. 5 will be referred to as the normal reading posture, and the posture in FIG. 6 will be referred to as the booklet reading posture. The normal reading posture is an example of the first posture of the device main body 2, and the booklet reading posture is an example of the second posture of the device main body 2.

[0029] 5 and 6 are angles formed between a reading conveyance path R2 (described later) and the device's placement surface G. The angle α2 in the booklet reading position is smaller than the angle α1 in the normal reading position. In the normal reading position, the projection area of the device body 2 onto the placement surface G on which the scanner 1 is placed is the smallest, that is, the footprint of the device body 2 is the smallest. In this specification, the footprint refers to the area occupied by the device body 2 in the XY plane when the device body 2 is viewed from above. The normal reading position is suitable for reading sheet-like documents, i.e., documents that have low rigidity and are easily bent, while the booklet reading position is suitable for reading documents that have high rigidity and are not easily bent, such as plastic cards or booklets.

[0030] In this embodiment, the posture of the device body 2 is changed and maintained by the power of a motor (not shown). However, the posture of the device body 2 may also be changed by the user applying force to the device body 2.

[0031] In FIG. 1, an operation unit 7 consisting of a plurality of operation buttons including a power button is provided on the front surface of the device. 2, a first connection portion 71, a second connection portion 72, and a third connection portion 73 are provided on the +X direction side of the side surfaces that form the periphery of the device. The first connection portion 71 is a connection portion to which a USB Type-A plug (not shown) is connected. The second connection portion 72 is a connection portion to which a USB Type-C plug (not shown) is connected. The third connection portion 73 is a connection portion to which a power plug (not shown) for supplying power to the device main body 2 is connected. Note that USB is an abbreviation for Universal Serial Bus, and Type-A and Type-C are each one of several types defined in the USB standard.

[0032] An external device can be connected via a USB cable (not shown), and a storage medium, such as a USB memory (not shown), can also be connected to the first connection unit 71. The control unit (not shown) of the scanner 1 can then save the read data in the storage medium connected to the first connection unit 71. Furthermore, an external device can be connected to the second connection section 72 via a USB cable (not shown). The first connection portion 71, the second connection portion 72, and the third connection portion 73 are provided on a circuit board (not shown) located on the rear side of the device. In this embodiment, the device main body 2 is configured so that it can also receive power from an external device connected to the second connection portion 72.

[0033] Next, the configuration of the document transport path in scanner 1 will be described with reference to Figures 5 and 6. The document to be fed is supported in an inclined position by document support section 11. Symbol P indicates the supported document. When multiple documents are supported on document support section 11, the top document is sent downstream by feed roller 14. Document support section 11 is formed in upper opening / closing section 10. Upper opening / closing section 10 is rotatable around a rotation axis (not shown), and opens and closes feed port 13 by rotating. Figure 1 shows the upper opening / closing section 10 in a closed state, and Figure 2 shows the upper opening / closing section 10 in an open state. Upper opening / closing section 10 constitutes first unit 3.

[0034] As shown in Fig. 3, the document support section 11 is provided with a pair of edge guides 12a, 12b that guide the side edges of the document. The pair of edge guides 12a, 12b are provided so as to be slidable in the document width direction (X-axis direction). The pair of edge guides 12a, 12b are provided so as to be interlocked by a rack and pinion mechanism (not shown) so as to move away from or towards each other across the center position in the document width direction. In other words, the scanner 1 employs a so-called center feeding system.

[0035] Returning to Figures 5 and 6, the feed roller 14 is provided in the second unit 4. The feed roller 14 receives power from a transport motor 50, which will be described later, and rotates. A separation roller 15 is provided in the first unit 3 at a position opposite the feed roller 14. A rotational torque is applied to the separation roller 15 by a torque limiter (not shown), which prevents double feeding of documents. The feed roller 14 and the separation roller 15 are provided at the center position in the document width direction (see FIG. 4). Instead of the separation roller 15, a separation pad may be provided. In addition, in this embodiment, the feed roller 14 is provided above the documents placed on the document support section 11, and the top document is fed first, but the feed roller 14 may be provided below the documents placed on the document support section 11, and the bottom document is fed first.

[0036] A first pair of conveying rollers 16 is provided downstream of the feed roller 14 and the separation roller 15. The first pair of conveying rollers 16 is composed of a first lower roller 17 provided in the first unit 3 and a first upper roller 18 provided in the second unit 4. The first upper roller 18 is provided so as to be able to move toward and away from the first lower roller 17, and is pressed against the first lower roller 17 by a pressing member (not shown), for example, a coil spring. Both the first lower roller 17 and the first upper roller 18 rotate by receiving power from a transport motor 50, which will be described later. Two first lower rollers 17 and two first upper rollers 18 are provided, one on each side of the center position in the document width direction (see FIG. 4). When the second unit 4 is closed relative to the first unit 3, the first lower roller 17 and the first upper roller 18 come into contact with each other. When the second unit 4 is opened relative to the first unit 3, the first upper roller 18 moves away from the first lower roller 17.

[0037] A first reading unit 32 and a second reading unit 33 are disposed facing each other downstream of the first transport roller pair 16. The first reading unit 32 is provided in the first unit 3, and the second reading unit 33 is provided in the second unit 4. The first reading unit 32 reads the bottom surface (first side) of the document supported by the document support unit 11, and the second reading unit 33 reads the top surface (second side) of the document supported by the document support unit 11. The second reading unit 33 is provided so as to be able to advance and retreat relative to the first reading unit 32, and is pressed toward the first reading unit 32 by a pressing member (not shown), for example, a coil spring. In this embodiment, the first reading unit 32 and the second reading unit 33 are configured by a contact image sensor module (CISM). Reference numeral 32a denotes a contact glass that configures the first reading unit 32, and reference numeral 33a denotes a contact glass that configures the second reading unit 33.

[0038] A second pair of transport rollers 20 is provided downstream of the first reading unit 32 and the second reading unit 33. The second pair of transport rollers 20 is composed of a second lower roller 21 provided in the first unit 3 and a second upper roller 22 provided in the second unit 4. The second upper roller 22 is provided so as to be able to move toward and away from the second lower roller 21, and is pressed against the second lower roller 21 by a pressing member (not shown), for example a coil spring. Both the second lower roller 21 and the second upper roller 22 rotate by receiving power from a transport motor 50, which will be described later. Two second lower rollers 21 and two second upper rollers 22 are provided, one on each side of the center position in the document width direction (see FIG. 4). When the second unit 4 is closed relative to the first unit 3, the second lower roller 21 and the second upper roller 22 come into contact with each other. When the second unit 4 is opened relative to the first unit 3, the second upper roller 22 moves away from the second lower roller 21.

[0039] 5 and 6, the dashed line indicated by the symbol R1 is the document feed path, and the document feed path R1 extends from the nip position between the feed roller 14 and the separation roller 15 to the nip position of the first transport roller pair 16. In addition, the dashed line indicated by the symbol R2 in Figures 5 and 6 is the reading transport path, and the reading transport path R2 extends from the nip position of the first transport roller pair 16 to the nip position of the second transport roller pair 20. The reading transport path R2 is a document transport path that faces the first reading unit 32 and the second reading unit 33.

[0040] When the device main body 2 is in the normal reading position shown in Fig. 5, a reverse conveyance path R3 is formed downstream of the reading conveyance path R2, along which the scanned document is reversed upward and discharged. The reverse conveyance path R3 is a document conveyance path downstream of the nip position of the second conveyance roller pair 20, and is a document conveyance path that curves and reverses a document conveyed diagonally downward as shown by the two-dot chain line in Fig. 5, and discharges the document diagonally upward from the first discharge opening 37. When the device main body 2 is in the booklet reading position shown in Fig. 6, a non-reversing conveyance path R4 is formed downstream of the reading conveyance path R2, along which the read document is discharged without being reversed. The non-reversing conveyance path R4 is a document conveyance path downstream of the nip position of the second conveyance roller pair 20, and is a document conveyance path for discharging the document, which is conveyed diagonally downward on the reading conveyance path R2 as shown by the two-dot chain line in Fig. 6, diagonally downward from the second discharge opening 38 without being curved or reversed. The second transport roller pair 20 functions as a discharge roller pair that discharges the document from the non-reverse transport path R4.

[0041] Switching between the reversing conveyance path R3 and the non-reversing conveyance path R4 is performed by a flap 35, which serves as a flap member constituting conveyance path switching means. The flap 35 is rotatable around a flap rotation axis 35a, and by rotating, connects the reversing conveyance path R3 to the reading conveyance path R2, or connects the non-reversing conveyance path R4 to the reading conveyance path R2. Connecting the reversing conveyance path R3 to the reading conveyance path R2 means making the reversing conveyance path R3 available, and making the non-reversing conveyance path R4 unavailable. Similarly, connecting the non-reversing conveyance path R4 to the reading conveyance path R2 means making the non-reversing conveyance path R4 available, and making the reversing conveyance path R3 unavailable.

[0042] In this embodiment, the flap 35 is configured to rotate in conjunction with the change in the position of the device main body 2. In this embodiment, a solenoid (not shown) is used as a configuration for rotating the flap 35 in conjunction with the change in the position of the device main body 2. A control unit (not shown) that performs various controls detects the position of the device main body 2 based on a detection signal from a position detection sensor (not shown), and based on that, drives the solenoid to rotate the flap 35. Note that the means for rotating the flap 35 is not limited to a solenoid, and other actuators such as a motor may also be used. Alternatively, the flap 35 may be configured to rotate mechanically in conjunction with the position of the device main body 2.

[0043] A third conveying roller pair 24 and a fourth conveying roller pair 28 are provided on the reverse conveying path R3. The third transport roller pair 24 is composed of a third drive roller 25 provided in the third unit 5 and a third driven roller 26 provided in the second unit 4. The third driven roller 26 is provided so as to be able to move toward and away from the third drive roller 25, and is pressed toward the third drive roller 25 by a pressing member (not shown), such as a coil spring. The third drive roller 25 is driven by the transport motor 50. The third driven roller 26 is a roller that is rotated by the conveyance motor 50.

[0044] The fourth transport roller pair 28 is composed of a fourth drive roller 29 provided in the third unit 5 and a fourth driven roller 30 provided in the second unit 4. The fourth driven roller 30 is provided so as to be able to move toward and away from the fourth drive roller 29, and is pressed toward the fourth drive roller 29 by a pressing member (not shown), such as a coil spring. The fourth drive roller 29 is driven by the transport motor 50. The fourth driven roller 30 is a roller that is rotated by the conveyor motor 50.

[0045] The third drive roller 25, the third driven roller 26, the fourth drive roller 29, and the fourth driven roller 30 are each provided in pairs, with the center position in the document width direction sandwiched between them (FIG. 3). When the third unit 5 is closed relative to the second unit 4, the third drive roller 25 and the third driven roller 26 come into contact, and the fourth drive roller 29 and the fourth driven roller 30 also come into contact. When the third unit 5 is opened relative to the second unit 4, the third drive roller 25 and the third driven roller 26 move apart, and the fourth drive roller 29 and the fourth driven roller 30 also move apart.

[0046] The document conveyed on the reverse conveying path R3 is discharged obliquely upward including a −Y direction component by the fourth conveying roller pair 28, and is supported in an inclined posture by the upper surface 4a of the second unit 4.

[0047] Next, a configuration for realizing the relative rotation of the first unit 3, the second unit 4, and the third unit 5 will be described. 9, a frame rotation shaft 64a protruding in the X-axis direction is integrally provided on the second frame 64 that constitutes the base of the second unit 4. Two frame rotation shafts 64a are provided spaced apart in the X-axis direction. 10, a bearing portion 63f is integrally provided on the first frame 63 that constitutes the base of the first unit 3. Two bearing portions 63f are provided spaced apart in the X-axis direction. The frame rotation shaft 64a of the second frame 64 is fitted into the bearing portion 63f, thereby enabling the second frame 64, i.e., the second unit 4, to rotate relative to the first frame 63, i.e., the first unit 3.

[0048] 11, a bearing portion 65a is integrally provided on a third frame 65 that constitutes the base of the third unit 5. Two bearing portions 65a are provided spaced apart in the X-axis direction. The frame rotation shaft 64a of the second frame 64 fits into the bearing portion 65a, making the third frame 65, i.e., the third unit 5, rotatable relative to the first unit 3 and the second unit 4. The third unit 5 can be opened and closed by rotating relative to the second unit 4 which is closed relative to the first unit 3, and can also be opened and closed by rotating relative to the second unit 4 which is open relative to the first unit 3.

[0049] In addition, the third frame 65 has two locking portions 65c spaced apart in the X-axis direction, and the locking portions 65c elastically engage with mating portions (not shown) formed on the second frame 64, thereby locking the third frame 65 to the second frame 64.

[0050] 7 is provided slidably in the X-axis direction relative to the second frame 64 of the second unit 4. The locking member 8 is pressed in the +X direction by a spring (not shown) on the second frame 64. The locking member 8 has an unlocking portion 8a, which is exposed at the top of the second unit 4 as shown in Figures 1 and 3. The user can unlock the second unit 4 from the first unit 3 by sliding the unlocking portion 8a in the -X direction, and open the second unit 4.

[0051] As shown in FIG. 8 , a first locking portion 63c and a second locking portion 63d are formed on the first frame 63 that constitutes the base of the first unit 3, with a gap in the X-axis direction. A first locked portion 8b and a second locked portion 8c are formed on the locking member 8 with a gap in the X-axis direction. As shown in FIG. 8 , the first locked portion 8b overlaps with the first locking portion 63c, and the second locked portion 8c overlaps with the second locking portion 63d, thereby locking the locking member 8, i.e., the second unit 4, to the first frame 63, i.e., the first unit 3. Sliding the locking member 8 in the −X direction from the state shown in FIG. 8 releases the overlap between the first locked portion 8b and the first locking portion 63c, and also releases the overlap between the second locked portion 8c and the second locking portion 63d. This releases the second unit 4 from the first unit 3, allowing the second unit 4 to be opened.

[0052] Next, the power transmission mechanism 79 that transmits power from the conveyance motor 50 to each roller will be described with reference to Fig. 12. The configuration shown in Fig. 12, excluding the various rollers and flap 35 already described, constitutes the power transmission mechanism 79. Note that in Fig. 12, reference symbols S1 to S7 all denote rotation axes. The rotation axes S1 to S7 are all axes whose rotation axis centers are parallel to the X-axis. The transport motor 50 is provided at the end of the first unit 3 in the -X direction. A drive pulley 51 is provided on the rotation shaft of the transport motor 50, and driving force is transmitted from the drive pulley 51 to a driven pulley 53 via a belt 52. A gear (not shown) is formed integrally with the driven pulley 53, and this gear meshes with a gear 54. A gear (not shown) is provided at the end of the rotation shaft S1 of the second lower roller 21 in the -X direction, and this gear meshes with the gear 54, driving the rotation shaft S1.

[0053] A gear group 80 is provided at the end of the device body 2 in the +X direction. The gear group 80 receives power from the rotation shaft S1 to rotate, and transmits the driving force to each roller. The gear group 80 will be described below with reference to Fig. 13. Note that the arrows attached to each gear in Figs. 13 to 15 indicate the direction of rotation of each gear when transporting a document. For convenience, each gear is given a name such as "first" or "second" to distinguish them. The gears shown in Figs. 13 to 15 all have their rotation axes parallel to the X-axis direction.

[0054] As described above, the rotation shaft S1 of the second lower roller 21 serves as the inlet for power transmission to the gear group 80. The rotation shaft S1 is supported by a bearing (not shown) provided in the first frame 63. The fourth gear 81 is provided on the rotation shaft S1.

[0055] A fifth gear 82 meshes with the fourth gear 81. The fifth gear 82 is supported by a gear shaft 63h provided on the first frame 63. The fifth gear 82 is in mesh with a sixth gear 83. The sixth gear 83 is provided on a rotation shaft S2. The rotation shaft S2 is supported by a bearing (not shown) that the first frame 63 has. A seventh gear 84 meshes with the sixth gear 83. The seventh gear 84 transmits power to a drive object (not shown).

[0056] Next, an eighth gear 85 meshes with the fourth gear 81. The eighth gear 85 is supported by a gear shaft 63g provided on the first frame 63. The eighth gear 85 is meshed with a first gear 86. The first gear 86 is supported by a gear shaft 64b provided on the second frame 64. The gear shaft 64b is coaxial with the frame rotation shaft 64a (see FIG. 9), and the rotation shaft center line L1 shown in FIG. 9 is the common rotation shaft center line of the gear shaft 64b and the second unit 4.

[0057] Returning to Fig. 13, the first gear 86 is in mesh with a second gear 87. The second gear 87 is supported on the second frame 64 by a support portion (not shown). The second gear 87 transmits a driving force to the rotation shaft S4 via a universal joint 96a, as shown in Fig. 12. A universal joint 96b is provided at the end of the rotation shaft S4 in the -X direction, and the driving force is transmitted to the second upper roller 22 via the universal joint 96b. Since the second upper roller 22 is displaceable relative to the second lower roller 21, the provision of the universal joints 96a and 96b allows power to be transmitted appropriately to the displaceable second upper roller 22.

[0058] 13, the second gear 87 is engaged with a ninth gear 88. The ninth gear 88 is supported by a gear shaft 64c provided on the second frame 64. A tenth gear 89 meshes with the ninth gear 88. The tenth gear 89 is supported on the second frame 64 by a support portion (not shown). The tenth gear 89 transmits a driving force to the rotation shaft S3 via a universal joint 95a, as shown in Fig. 12. A universal joint 95b is provided at the end of the rotation shaft S3 in the -X direction, and the driving force is transmitted to the first upper roller 18 via the universal joint 95b. Since the first upper roller 18 is displaceable relative to the first lower roller 17, the provision of the universal joints 95a and 95b allows power to be transmitted appropriately to the displaceable first upper roller 18.

[0059] 13, an eleventh gear 90 meshes with the tenth gear 89. The eleventh gear 90 is supported by a gear shaft 64d provided on the second frame 64. The eleventh gear 90 transmits power to a twelfth gear 91. The twelfth gear 91 transmits power to the feed roller 14 via a rotation shaft S5 as shown in FIG.

[0060] 13, a third gear 92 meshes with the first gear 86. The third gear 92 is supported by a gear shaft 65b provided on the third frame 65. The third gear 92 is in mesh with a thirteenth gear 93 and a fourteenth gear 94 . The thirteenth gear 93 is provided on the rotation shaft S6. The rotation shaft S6 is supported by a bearing (not shown) provided in the third frame 65. The thirteenth gear 93 transmits power to the third drive roller 25 via the rotation shaft S6. The fourteenth gear 94 is provided on a rotation shaft S7. The rotation shaft S7 is supported by a bearing (not shown) provided in the third frame 65. The fourteenth gear 94 transmits power to the fourth drive roller 29 via the rotation shaft S7.

[0061] The configuration and effects of the scanner 1 described above can be summarized as follows. That is, the scanner 1 comprises a first unit 3 and a second unit 4 that is rotatable relative to the first unit 3 and opens and closes relative to the first unit 3 by rotating. The first unit 3 comprises a transport motor 50. When the second unit 4 is closed relative to the first unit 3, a reading transport path R2 for transporting the document is formed, and when the second unit 4 is opened relative to the first unit 3, the reading transport path R2 is opened. The power transmission mechanism 79 transmits the power of the conveyance motor 50 from the first unit 3 to the second unit 4. The power transmission mechanism 79 is characterized by having a first gear 86 that has a common rotation axis center with the rotation axis center of the second unit 4, and a second gear 87 that is a gear provided on the second unit 4 and meshes with the first gear 86.

[0062] 13 to 14, even if the second unit 4 is opened, the second gear 87 performs planetary motion around the first gear 86, but the meshing between the second gear 87 and the first gear 86 is not released. With this configuration, it is possible to appropriately maintain backlash in the meshing between the first gear 86 and the second gear 87, and to suppress problems associated with fluctuations in backlash. The second gear 87 rotates in the opposite direction to the rotation direction of the first gear 86 when the document is transported by the first transport roller pair 16 and the second transport roller pair 20. When the second unit 4 is opened, the second gear 87 rotates in the opposite direction to the rotation direction of the second gear 87 when the document is transported by the first transport roller pair 16 and the second transport roller pair 20. When the second unit 4 is closed, the second gear 87 rotates in the same direction as the rotation direction of the second gear 87 when the document is transported by the first transport roller pair 16 and the second transport roller pair 20.

[0063] In this embodiment, the transport motor 50 is provided in the first unit 3, and the power transmission mechanism 79 transmits the power of the transport motor 50 from the first unit 3 to the second unit 4. However, the transport motor 50 may also be provided in the second unit 4, and the power transmission mechanism 79 may transmit the power of the transport motor 50 from the second unit 4 to the first unit 3.

[0064] In addition, in this embodiment, as described with reference to Figure 9, the gear shaft 64b that supports the first gear 86 is formed separately from the frame rotation shaft 64a in the second frame 64, but the first gear 86 may also be supported by the frame rotation shaft 64a. 9, the gear shaft 64b supporting the first gear 86 is provided on the second frame 64, but the gear shaft 64b is not limited to this and may be formed on the first frame 63 constituting the base of the first unit 3 or on the third frame 65 constituting the base of the third unit 5. Alternatively, the gear shaft 64b may be a separate, independent shaft member, not formed integrally with either frame. In this embodiment, the gear (eighth gear 85) is used to transmit power to the first gear 86, but this is not limited to a gear and may be a belt. Also, the first gear 86 may be mounted on the drive shaft of a motor so that the first gear 86 is directly driven by the motor.

[0065] The first unit 3 is provided with a first reading section 32, and the second unit 4 is provided with a second reading section 33. A first transport roller pair 16 is provided upstream of the first reading section 32 and the second reading section 33 in the document transport path, and a second transport roller pair 20 is provided downstream of the first reading section 32 and the second reading section 33 in the document transport path. The first transport roller pair 16 includes a first lower roller 17 that comes into contact with the underside of the document being transported in the first unit 3, and a first upper roller 18 that comes into contact with the top side of the document being transported in the second unit 4. The second transport roller pair 20 includes a second lower roller 21 that comes into contact with the underside of the document in the first unit 3, and a second upper roller 22 that comes into contact with the top side of the document in the second unit 4. The transport motor 50 drives the first lower roller 17, first upper roller 18, second lower roller 21, and second upper roller 22 via a power transmission mechanism 79. In other words, because all of these rollers are driven by the transport motor 50, thick documents can be transported reliably.

[0066] Furthermore, the first upper roller 18 is movable toward and away from the first lower roller 17 and is pressed toward the first lower roller 17, and the second upper roller 22 is movable toward and away from the second lower roller 21 and is pressed toward the second lower roller 21. As a result, the second unit 4, which includes the first upper roller 18 and the second upper roller 22, receives a force in the opening direction from the first unit 3 when in the closed state. Hereinafter, this force will be referred to as the first force. When the document is transported by the first transport roller pair 16 and the second transport roller pair 20, the first gear 86 rotates in such a way that the first gear 86 applies a force to the second gear 87 in the direction of opening the second unit 4. Hereinafter, this force will be referred to as the second force. Since the first force and the second force both act in the direction that opens the second unit 4, the amount of backlash between the first gear 86 and the second gear 87 is stabilized compared to a configuration in which the first force and the second force act on the second unit 4 in opposite directions.

[0067] The scanner 1 is also provided with a third unit 5 that is rotatable relative to the first unit 3 and the second unit 4 and that rotates to open and close relative to the first unit 3 and the second unit 4. When the third unit 5 is closed, a reverse conveying path R3 is formed, and when the third unit 5 is opened, the reverse conveying path R3 is opened. The center of rotation of the third unit 5 is common to the center of rotation of the second unit 4, and the power transmission mechanism 79 has a third gear 92, which is a gear provided on the third unit 5 and meshes with the first gear 86. 13 to 15, even if the third unit 5 is opened, the third gear 92 performs planetary motion around the first gear 86, but the meshing between the third gear 92 and the first gear 86 is not released. With this configuration, it is possible to maintain an appropriate backlash in the meshing between the first gear 86 and the third gear 92, and to suppress problems associated with fluctuations in backlash.

[0068] It should be noted that the state shown in Figure 14, i.e., the state in which the second unit 4 is open relative to the first unit 3 and the third unit 5 is closed relative to the second unit 4, is not shown in the figure, but it goes without saying that even in this case, the meshing between the third gear 92 and the first gear 86 is maintained. Furthermore, although the scanner 1 in this embodiment includes the third unit 5, the scanner 1 may not necessarily include the third unit 5.

[0069] The scanner 1 also has a document transport path downstream of the reading transport path R2, which is a reversing transport path R3 for discharging a document that has been read by inverting it face up, a document transport path downstream of the reading transport path R2, which is a non-reversing transport path R4 for discharging a document that has been read without inverting it, and a flap 35 as a transport path switching means for switching the document transport path connected to the reading transport path R2 to either the reversing transport path R3 or the non-reversing transport path R4. The reverse transport path R3 includes a third transport roller pair 24 and a fourth transport roller pair 28 located downstream thereof. The reverse transport path R3 is formed between the second unit 4 and the third unit 5. The third transport roller pair 24 includes a third drive roller 25 that comes into contact with the underside of the document in the third unit 5 and is driven by the transport motor 50, and a third driven roller 26 that comes into contact with the upper side of the document in the second unit 4 and is driven to rotate in contact with the document. The fourth transport roller pair 28 includes a fourth drive roller 29 that comes into contact with the underside of the document in the third unit 5 and is driven by the transport motor 50, and a fourth driven roller 30 that comes into contact with the upper side of the document in the second unit 4 and is driven to rotate in contact with the document. With the above configuration, it is possible to switch between the reversing conveying path R3 and the non-reversing conveying path R4, and therefore, by using the non-reversing conveying path R4, it is possible to smoothly convey documents that are difficult to bend.

[0070] The third driven roller 26 is movable toward and away from the third drive roller 25 and is pressed toward the third drive roller 25, and the fourth driven roller 30 is movable toward and away from the fourth drive roller 29 and is pressed toward the fourth drive roller 29. As a result, the third unit 5 receives a force in the opening direction from the second unit 4 when in the closed state. Hereinafter, this force will be referred to as the third force. When the document is transported by the third transport roller pair 24 and the fourth transport roller pair 28, the first gear 86 rotates in such a way that the first gear 86 applies a force to the third gear 92 in the direction of opening the third unit 5. Hereinafter, this force will be referred to as a fourth force. Since the third force and the fourth force both act in the direction that opens the third unit 5, the amount of backlash between the first gear 86 and the third gear 92 is stabilized compared to a configuration in which the third force and the fourth force act in opposite directions on the third unit 5.

[0071] 12 and 13, the gears that constitute the power transmission mechanism 79 and are provided in the first unit 3, specifically the seventh gear 84, the sixth gear 83, the fifth gear 82, the fourth gear 81, and the eighth gear 85, are arranged along the reading conveying path R2 on the +X-direction side of the first frame 63 that constitutes the base of the first unit 3. Furthermore, the gears that make up the power transmission mechanism 79 and are provided in the second unit 4, specifically the twelfth gear 91, the eleventh gear 90, the tenth gear 89, the ninth gear 88, the second gear 87, and the first gear 86, are arranged along the reading conveyance path R2 on the side surface in the +X direction of the second frame 64 that makes up the base of the second unit 4. This makes it possible to prevent the device from becoming large.

[0072] Furthermore, 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 in the scope of the present invention. [Explanation of symbols]

[0073] 1...scanner, 2...device main body, 3...first unit, 4...second unit, 4a...top surface, 5...third unit, 6...main body support section, 6c...main body rotation shaft, 7...operation section, 8...locking member, 8a...unlocking section, 8b...first locked section, 8c...second locked section, 10...upper opening / closing section, 11...document support section, 12a, 12b...edge guide, 13...feed slot, 14...feed roller, 15...separation roller, 16...first pair of transport rollers, 17...first lower roller, 18...first upper roller, 20...second pair of transport rollers, 21...second lower roller, 22...second upper roller, 24...third pair of transport rollers, 25...third drive roller, 26...third driven roller, 28...fourth pair of transport rollers, 2 9...fourth drive roller, 30...fourth driven roller, 32...first reading unit, 32a...contact glass, 33...second reading unit, 33a...contact glass, 35...flap, 35a...flap rotation shaft, 37...first discharge port, 38...second discharge port, 50...conveyor motor, 51...drive pulley, 52...belt, 53...driven pulley, 54...gear, 63...first frame, 63a...boss, 63b...supported portion, 63c...first locking portion, 63d...second locking portion, 63f...bearing portion, 63g, 63h...gear shaft, 64...second frame, 64a...frame rotation shaft, 64b...gear shaft, 65...third frame, 65a...bearing portion, 65b...gear shaft, 66...rear cover, 71...first connection portion (USB Type-A), 72...Second connection part (USB Type-C), 73...Third connection part (DC jack), 79... power transmission mechanism, 80... gear group, 81... fourth gear, 82... fifth gear, 83... sixth gear, 84...7th gear, 85...8th gear, 86...1st gear, 87...2nd gear, 88...9th gear, 89...10th gear, 90...11th gear, 91...12th gear, 92...3rd gear, 93...13th gear, 94...14th gear, 95a, 95b...universal joint, 96a, 96b...universal joint, R1: Document feed path, R2: Reading path, R3: Reversing path, R4: Non-reversing path

Claims

1. A first unit; a second unit that is rotatable relative to the first unit and that opens and closes relative to the first unit by rotating; a motor provided in the first unit or the second unit; a power transmission mechanism that transmits power of the motor from the first unit to the second unit or from the second unit to the first unit; a document transport path for transporting a document; a first reading unit provided in the first unit for reading an image of a document transported through the document transport path; a second reading unit provided in the second unit for reading an image of the document transported through the document transport path; a first transport roller pair that is a roller pair driven by the motor via the power transmission mechanism and is located upstream of the document transport path with respect to the first reading unit and the second reading unit; a second transport roller pair that is a roller pair driven by the motor via the power transmission mechanism and is located downstream of the document transport path with respect to the first reading unit and the second reading unit; Equipped with When the second unit is closed relative to the first unit, the document transport path is formed, and when the second unit is opened relative to the first unit, the document transport path is opened; the power transmission mechanism includes a first gear having a common rotation axis center with the second unit; a second gear provided in the second unit and meshing with the first gear, the first transport roller pair includes a first lower roller in the first unit that comes into contact with a lower surface of the document transported along the reading transport path, and a first upper roller in the second unit that comes into contact with an upper surface of the document transported along the reading transport path, the second conveying roller pair includes a second lower roller that contacts the lower surface of the document in the first unit and a second upper roller that contacts the upper surface of the document in the second unit; the first upper roller is movable toward and away from the first lower roller and is pressed toward the first lower roller; the second upper roller is movable toward and away from the second lower roller and is pressed toward the second lower roller; a rotation direction of the first gear when the document is transported by the first transport roller pair and the second transport roller pair is a direction in which the first gear applies an external force to the second gear in a direction in which the second unit is opened; An image reading device characterized by:

2. 2. The image reading device according to claim 1, further comprising a third unit that is rotatable relative to the first unit and the second unit and that opens and closes relative to the first unit and the second unit by rotating; the third unit has a common rotation axis center with the second unit; the power transmission mechanism includes a third gear provided in the third unit and meshing with the first gear; An image reading device characterized by:

3. A first unit; a second unit that is rotatable relative to the first unit and that opens and closes relative to the first unit by rotating; a motor provided in the first unit or the second unit; a power transmission mechanism that transmits power of the motor from the first unit to the second unit or from the second unit to the first unit; a document transport path for transporting a document; a first reading unit provided in the first unit for reading an image of a document transported through the document transport path; a second reading unit provided in the second unit for reading an image of the document transported through the document transport path; a first transport roller pair located upstream of the document transport path with respect to the first reading unit and the second reading unit; a second transport roller pair located downstream of the document transport path relative to the first reading unit and the second reading unit; a third unit that is rotatable relative to the first unit and the second unit and that opens and closes relative to the first unit and the second unit by rotating; Equipped with When the second unit is closed relative to the first unit, the document transport path is formed, and when the second unit is opened relative to the first unit, the document transport path is opened; the power transmission mechanism includes a first gear having a common rotation axis center with the second unit; a second gear provided in the second unit and meshing with the first gear, the first transport roller pair includes a first lower roller in the first unit that comes into contact with a lower surface of the document transported along the reading transport path, and a first upper roller in the second unit that comes into contact with an upper surface of the document transported along the reading transport path, the second conveying roller pair includes a second lower roller that contacts the lower surface of the document in the first unit and a second upper roller that contacts the upper surface of the document in the second unit; the motor drives the first lower roller, the first upper roller, the second lower roller, and the second upper roller via the power transmission mechanism; the third unit has a common rotation axis center with the second unit; the power transmission mechanism includes a third gear provided in the third unit and meshing with the first gear; An image reading device characterized by:

4. 4. The image reading device according to claim 3, wherein the document transport path between the first transport roller pair and the second transport roller pair is a reading transport path, and a document transport path downstream of the reading transport path is a reversing transport path for reversing the read document upward and discharging the document; a non-reversing conveyance path, which is a document conveyance path downstream of the reading conveyance path, for discharging a read document without reversing it; a transport path switching unit for switching the document transport path connected to the reading transport path between the reverse transport path and the non-reverse transport path; a third conveyance roller pair provided in the reverse conveyance path and positioned downstream of the second conveyance roller pair; a fourth conveyance roller pair that is a roller pair provided in the reverse conveyance path and is located downstream of the third conveyance roller pair, the reverse conveying path is formed between the second unit and the third unit, the third transport roller pair includes a third drive roller that is a roller that comes into contact with the lower surface of the document in the third unit and is driven by the motor, and a third driven roller that is a roller that comes into contact with the upper surface of the document in the second unit and comes into contact with the document and is rotated by the document; the fourth transport roller pair includes a fourth drive roller that is a roller that comes into contact with the lower surface of the document in the third unit and is driven by the motor, and a fourth driven roller that is a roller that comes into contact with the upper surface of the document in the second unit and comes into contact with the document and rotates in response to the document; An image reading device characterized by:

5. 5. The image reading apparatus according to claim 4, the third driven roller is movable toward and away from the third drive roller and is pressed toward the third drive roller; the fourth driven roller is movable toward and away from the fourth drive roller and is pressed toward the fourth drive roller, a rotation direction of the first gear when the document is transported by the third transport roller pair and the fourth transport roller pair is a direction in which the first gear applies a force to the third gear in a direction in which the third unit is opened; An image reading device characterized by:

6. 6. The image reading device according to claim 4, wherein the gears constituting the power transmission mechanism and provided in the first unit are arranged along the reading conveyance path on a side surface of a first frame constituting a base of the first unit, the plurality of gears constituting the power transmission mechanism and provided in the second unit are arranged along the reading conveyance path on a side surface of a second frame constituting a base of the second unit; An image reading device characterized by:

7. A first unit; a second unit that is rotatable relative to the first unit and that opens and closes relative to the first unit by rotating; a motor provided in the first unit or the second unit; a power transmission mechanism that transmits power of the motor from the first unit to the second unit or from the second unit to the first unit; a document transport path for transporting a document; a first reading unit provided in the first unit for reading an image of a document transported through the document transport path; a second reading unit provided in the second unit for reading an image of the document transported through the document transport path; a first transport roller pair located upstream of the document transport path with respect to the first reading unit and the second reading unit; a second transport roller pair located downstream of the document transport path relative to the first reading unit and the second reading unit; Equipped with When the second unit is closed relative to the first unit, the document transport path is formed, and when the second unit is opened relative to the first unit, the document transport path is opened; the power transmission mechanism includes a first gear having a common rotation axis center with the second unit; a second gear provided in the second unit and meshing with the first gear, the first transport roller pair includes a first lower roller in the first unit that comes into contact with a lower surface of the document transported along the reading transport path, and a first upper roller in the second unit that comes into contact with an upper surface of the document transported along the reading transport path, the second conveying roller pair includes a second lower roller that contacts the lower surface of the document in the first unit and a second upper roller that contacts the upper surface of the document in the second unit; the motor drives the first lower roller, the first upper roller, the second lower roller, and the second upper roller via the power transmission mechanism; the first upper roller is movable toward and away from the first lower roller and is pressed toward the first lower roller; the second upper roller is movable toward and away from the second lower roller and is pressed toward the second lower roller; The power of the motor is transmitted to the first upper roller and the second upper roller by a universal joint. An image reading device characterized by:

8. In the image reading device according to claim 1 or claim 2, the motor drives the first lower roller, the first upper roller, the second lower roller, and the second upper roller via the power transmission mechanism; An image reading device characterized by:

Images