Medium discharge device, image reading device

Abstract

To solve the problem that lubricant moves onto the ejection assist member that sends out medium rear end in the ejection direction and the medium is made dirty.SOLUTION: A medium discharge device includes a discharge drive roller which is a roller in contact with a first surface of the medium, receives driving force from a drive source to rotate, a discharge following roller which is a roller in contact with a second surface opposite to the first surface of the medium and which rotates by nipping the medium in the space with the discharge drive roller; a following roller shaft which is the rotation shaft of the discharge following roller; and a discharge auxiliary member which is a member in contact with the second surface of the medium being discharged, has a larger diameter than the discharge following roller and rotates integrally with the discharge following roller; the discharge following roller has a shaft hole through which the following roller shaft passes, and as the discharge following roller rotates, the inner surface of the shaft hole slides against the outer surface of the following roller shaft, and quick-drying lubricant is used between the inner surface of the shaft hole and the outer surface of the following roller shaft.SELECTED DRAWING: Figure 14

Description

[Technical field]

[0001] The present invention relates to a medium ejection device that ejects a medium, and an image reading device that includes the medium ejection device. [Background technology]

[0002] When a medium is discharged outside a printer or scanner by a pair of rollers, a configuration may be adopted in which a convex portion with a larger diameter than the roller is provided so that the rear end of the medium can be reliably removed from the pair of rollers, and this convex portion sends the rear end of the medium in the discharge direction, as shown in Patent Document 1. Patent Document 1 also describes that the convex portion may be made of urethane foam. In the following description, such a convex portion will be referred to as a discharge assist member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 05-092631 Summary of the Invention [Problem to be solved by the invention]

[0004] A lubricant is often used on the sliding surface of the roller shaft. The sliding surface here refers to a part of the outer circumferential surface of the roller shaft that slides against other members. However, there are cases where a part of the lubricant moves to the discharge assisting member and adheres to the medium, causing the medium to become dirty. In particular, when the discharge assisting member is made of an elastic material, the discharge assisting member has a tendency to absorb the lubricant, which then adheres to the medium and causes the medium to become dirty, leaving room for improvement. [Means for solving the problem]

[0005] In order to solve the above problem, the media discharge device of the present invention comprises an discharge drive roller which is a roller in contact with a first side of the medium being discharged and rotates with power from a drive source, an discharge driven roller which is a roller in contact with a second side opposite to the first side of the medium being discharged and which rotates by nipping the medium between the discharge drive roller and the discharge driven roller, a driven roller shaft which is the rotation shaft of the discharge driven roller, and an discharge auxiliary member which is a member in contact with the second side of the medium being discharged and has a larger diameter than the discharge driven roller and rotates integrally with the discharge driven roller, wherein the discharge driven roller has an axle through which the driven roller shaft passes, and as the discharge driven roller rotates, the inner surface of the axle hole slides against the outer surface of the driven roller shaft, and a quick-drying lubricant is used between the inner surface of the axle hole and the outer surface of the driven roller shaft.

[0006] The image reading device of the present invention is characterized by including the medium ejection device and a reading section that is located upstream of the medium ejection device in a medium transport path and that reads the medium. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a front perspective view of the scanner with the main body in a normal reading position. [Diagram 2] 4 is a cross-sectional view of the document transport path of the scanner when the device body is in the normal reading position, as viewed from the width direction. [Diagram 3] 1 is a cross-sectional view of a document transport path of the scanner when the device body is in a booklet reading position, as viewed from the width direction. [Figure 4] FIG. 4 is a side cross-sectional view of the medium ejection device as viewed from the width direction. [Diagram 5] 5 is a view taken in the direction of arrow A in FIG. 4 . [Figure 6] FIG. [Figure 7] FIG. [Figure 8] FIG. 4 is a perspective view of a third driven roller, a fourth driven roller, and a double torsion spring. [Figure 9] FIG. [Figure 10] FIG. 4 is a side view of a third driven roller, a fourth driven roller, and a double torsion spring. [Figure 11] 6 is a diagram showing a state in which the fourth driven roller and the first discharge auxiliary member are displaced from the state in FIG. 5. [Figure 12] FIG. 11 is a perspective view of a medium ejection device according to another embodiment. [Figure 13] FIG. 11 is a perspective view of a medium ejection device according to another embodiment. [Figure 14] FIG. 11 is a cross-sectional perspective view of a fourth driven roller and a driven roller shaft. [Figure 15] 4 is a diagram showing the positional relationship between a first discharge auxiliary member, a drive roller shaft, and a regulating portion. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The present invention will now be briefly described. The media discharge device according to a first aspect comprises an discharge drive roller which is a roller in contact with a first surface of the medium being discharged and which rotates with power from a drive source; an discharge driven roller which is a roller in contact with a second surface opposite to the first surface of the medium being discharged and which rotates by nipping the medium between the discharge drive roller and the discharge driven roller; a driven roller shaft which is the rotation shaft of the discharge driven roller; and an discharge auxiliary member which is a member in contact with the second surface of the medium being discharged and has a larger diameter than the discharge driven roller and rotates integrally with the discharge driven roller, wherein the discharge driven roller has an axle through which the driven roller shaft passes, and as the discharge driven roller rotates, the inner surface of the axle hole slides against the outer surface of the driven roller shaft, and a quick-drying lubricant is used between the inner surface of the axle hole and the outer surface of the driven roller shaft.

[0009] According to the present aspect, a quick-drying lubricant is used as a lubricant between the inner surface of the shaft hole and the outer surface of the driven roller shaft, thereby preventing the lubricant from migrating to the discharge auxiliary member and preventing the lubricant from adhering to the medium and soiling the medium. In this specification, the discharge auxiliary member having a larger diameter than the discharge driven roller means that the maximum diameter of the discharge auxiliary member is larger than the maximum diameter of the discharge driven roller. Therefore, the discharge auxiliary member is not limited to a shape having a uniform diameter along the circumferential direction.

[0010] A second aspect is an aspect dependent on the first aspect, characterized in that the discharge driven roller has a flange portion, and the discharge assistant member is provided on the flange portion. According to this aspect, the discharge driven roller has a flange portion and the discharge auxiliary member is provided on the flange portion. Therefore, when a lubricant is interposed between the inner surface of the shaft hole and the outer surface of the driven roller shaft, some of the lubricant is likely to migrate to the discharge auxiliary member and cause damage to the medium. However, the effect of the first aspect described above makes it possible to prevent the lubricant from adhering to the medium and causing damage to the medium.

[0011] A third aspect is an aspect dependent on the first aspect, characterized in that the discharge assistance member is made of an elastic material. According to this aspect, since the ejection assistance member is made of an elastic material, it is possible to suitably push out the rear end of the medium in the ejection direction. Here, if the discharge assisting member is formed from an elastic material, the discharge assisting member is likely to absorb the lubricant and adhere to the medium, thereby soiling the medium; however, the effect of the first aspect described above can prevent the lubricant from adhering to the medium and soiling the medium. Incidentally, this aspect is not limited to the above-mentioned first aspect, and may be subordinate to the above-mentioned second aspect.

[0012] A fourth aspect is an aspect dependent on the third aspect, characterized in that the discharge assistant member has a plurality of protrusions on the outer periphery along the circumferential direction. According to this aspect, the ejection assistant member has a plurality of protrusions on its outer periphery along the circumferential direction, so that the trailing end of the medium can be appropriately sent out in the ejection direction. Here, when the discharge assisting member is configured to have multiple protrusions along the circumferential direction on its outer periphery, the protrusions may press hard against the medium, and when the discharge assisting member absorbs lubricant, the lubricant is likely to adhere to the medium from the protrusions, i.e., the medium is likely to be soiled. However, due to the effect of the first aspect described above, it is possible to prevent the lubricant from adhering to the medium and causing the medium to become soiled.

[0013] A fifth aspect is an aspect dependent on the first aspect, and is characterized in that it comprises a drive roller shaft which is a rotation shaft of the discharge drive roller, and a regulating portion which regulates the bending of the drive roller shaft, and the quick-drying lubricant is applied to a position on the outer peripheral surface of the drive roller shaft which faces the regulating portion.

[0014] According to this aspect, the regulating portion can suppress the deflection of the driving roller shaft. Also, since the quick-drying lubricant is applied to a portion of the outer circumferential surface of the driving roller shaft that faces the regulating portion, an increase in the rotation load of the driving roller shaft when the driving roller shaft abuts against the regulating portion can be suppressed. Here, if a lubricant is applied to the outer peripheral surface of the drive roller shaft, there is a risk that some of the lubricant will move to the discharge auxiliary member and adhere to the medium, causing the medium to become soiled. However, according to the present embodiment, the quick-drying lubricant is applied to the outer peripheral surface of the drive roller shaft at a position opposite the regulating portion, thereby preventing the lubricant from migrating to the discharge auxiliary member and preventing the lubricant from adhering to the medium and soiling the medium. Incidentally, this aspect is not limited to the above-mentioned first aspect, and may be subordinate to any of the above-mentioned second to fourth aspects.

[0015] A sixth aspect is an aspect dependent on the first aspect, characterized in that the driven roller shaft has a sliding portion at another portion in addition to the portion facing the inner circumferential surface of the shaft hole, and a non-drying lubricant is used at the sliding portion.

[0016] According to this aspect, the driven roller shaft has a sliding portion at another portion in addition to the portion facing the inner circumferential surface of the shaft hole, and in the configuration in which a non-quick-drying lubricant is used at the sliding portion, the effect of the first aspect described above can be obtained. Incidentally, this aspect is not limited to the above-mentioned first aspect, and may be subordinate to any of the above-mentioned second to fifth aspects.

[0017] A seventh aspect is an aspect dependent on the first aspect, characterized in that the discharge auxiliary member is a first discharge auxiliary member, and the discharge auxiliary member is a member that contacts the second surface of the medium to be discharged, has a larger diameter than the discharge driven roller, and rotates integrally with the discharge driven roller, the second discharge auxiliary member is positioned outboard of the first discharge auxiliary member in a width direction that intersects with the medium discharge direction, the discharge driven roller and the first discharge auxiliary member are arranged to be displaceable in a direction toward and away from the discharge drive roller, and the torque of the discharge driven roller is transmitted to the second discharge auxiliary member via a shaft and a universal joint.

[0018] When the discharge assist member is provided near the center in the width direction, it is not possible to impart a sending effect in the discharge direction to the side edge of the trailing end of the medium. Note that, hereinafter, the sending effect in the discharge direction imparted to the trailing end of the medium may be referred to as a kicking effect. In particular, the side edges of the trailing edge of the medium are prone to curling, and if the discharge assist member is provided near the center in the width direction, the trailing edge of the medium cannot be properly kicked out. Therefore, in order to impart a kicking effect to the side edges of the trailing edge of the medium, it is necessary to provide the discharge assist member at an additional side edge position. However, in order to rotate the discharge assist member provided at the side end position, it is necessary to extend the driven roller shaft further in the axial direction and transmit torque from the driven roller shaft to the discharge assist member. In this case, if the discharge driven roller is provided so as to be displaceable according to the thickness of the medium, the discharge assist member will also be displaced, and it will not be possible to provide an appropriate kick-out effect to the side edge of the curled rear end of the medium.

[0019] However, according to this aspect, since the second discharge auxiliary member is provided outside the first discharge auxiliary member in the width direction, a kick-out effect can be imparted to the side edge of the trailing end of the medium or its vicinity. And since the torque of the discharge driven roller is transmitted to the second discharge auxiliary member via a shaft and a universal joint, the second discharge auxiliary member can easily maintain its position relative to the medium even if the discharge driven roller is displaced, and a kick-out effect can be imparted to the side edge of the trailing end of the medium or its vicinity without being affected by the displacement of the discharge driven roller. In this specification, the side edge of the trailing end of the medium means the side edge in the width direction at the trailing end of the medium, and the outside in the width direction means the direction from the center position in the width direction of the medium toward the side edge. Incidentally, this aspect is not limited to the above-mentioned first aspect, and may be subordinate to any of the above-mentioned second to sixth aspects.

[0020] The eighth aspect is a dependent aspect of the seventh aspect, and is characterized in that the universal joint is a first universal joint, and between the discharge driven roller and the second discharge auxiliary member, the first universal joint and a second universal joint positioned outside the first universal joint in the width direction are provided, the second discharge auxiliary member is provided at a position adjacent to the second universal joint in the width direction, and the quick-drying lubricant is used in the second universal joint.

[0021] According to the present aspect, the universal joint is a first universal joint, and between the discharge driven roller and the second discharge auxiliary member, the first universal joint and a second universal joint positioned outside the first universal joint in the width direction are provided, so that when the discharge driven roller is displaced, the second discharge auxiliary member is more likely to maintain its posture as well as its position relative to the medium. In addition, since the second discharge auxiliary member is provided at a position adjacent to the second universal joint in the width direction, if a lubricant is applied to the second universal joint, some of the lubricant is likely to migrate to the second discharge auxiliary member and easily soil the medium. However, since a quick-drying lubricant is used for the second universal joint, the migration of the lubricant from the second universal joint to the second discharge auxiliary member can be prevented, and the lubricant can be prevented from adhering to the medium and soiling the medium.

[0022] The image reading device of the 9th aspect is characterized in that it comprises the medium ejection device of any of the 1st to 8th aspects, and a reading unit that is located upstream of the medium ejection device on the medium transport path and reads the medium. According to this aspect, in the image reading device, the operational effects of any one of the first to eighth aspects described above can be obtained.

[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 a first side and an opposite second side of a document is taken as an example. The scanner 1 is a so-called sheet-fed type scanner that reads a document, which is an example of a medium, while moving it toward a reading unit described later. In this specification, the document includes not only sheet-shaped documents, but also card-shaped documents and booklet-shaped documents.

[0024] In the XYZ coordinate system shown in each drawing, the X-axis direction is the width direction of the device and the width direction of the document, 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." In addition, in the following description of different embodiments, the same components will be denoted by the same reference numerals, and duplicate descriptions will be avoided.

[0025] In FIG. 1, a scanner 1 includes a device main body 2 and a body support part 6 that supports the device main body 2 rotatably. 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 can rotate integrally around a rotation axis (not shown) relative to the first unit 3. Reference symbol 8a denotes an unlocking portion, and the user can unlock the second unit 4 and the third unit 5 relative to the first unit 3 by sliding the unlocking portion 8a in the -X direction. By rotating the second unit 4 and the third unit 5 relative to the first unit 3, a document feed path R1 and a reading transport path R2 (described later) can be exposed. In addition, the third unit 5 can rotate about a rotation axis (not shown) relative to the first unit 3 and the second unit 4. By rotating the third unit 5 relative to the first unit 3 and the second unit 4, a reverse conveying path R3 (described later) can be exposed.

[0027] The device body 2 is rotatable around the body rotation axis 6c (see Figures 2 and 3) relative to the body support part 6. In this embodiment, the device body 2 can hold two postures by rotating. The two postures of the device body 2 are shown in Figures 2 and 3, and hereinafter the posture in Figure 2 will be referred to as the normal reading posture, and the posture in Figure 3 will be referred to as the booklet reading posture. The normal reading posture of the device body 2 is a posture in which the reading conveying path R2 is connected to the reversing conveying path R3. The booklet reading posture of the device body 2 is a posture in which the reading conveying path R2 is connected to the non-reversing conveying path R4.

[0028] In this embodiment, the position of the device body 2 is changed by the user applying an external force to the device body 2. The normal reading position and the booklet reading position of the device body 2 are each maintained by a snap fit portion (not shown). It is also preferable to provide a handle portion on the device body 2 to improve the operability of the user's position changing operation. Further, instead of a configuration in which the user applies an external force to the device body 2 to switch the position of the device body 2, a configuration in which the device body 2 is rotated by the power of a motor or the like to switch the position may be used.

[0029] 2 and 3 are angles between a reading conveyance path R2 (described later) and a placement surface G of the device. 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, this is the position in which the footprint of the device body 2 is the smallest. In this specification, the footprint refers to the area that the device body 2 occupies in the XY plane when the device body 2 is viewed from above. The normal reading position is suitable for reading a sheet-like document, that is, a document that has low rigidity and is easily bent, whereas the booklet reading position is suitable for reading a document that has high rigidity and is not easily bent, such as a plastic card or booklet.

[0030] As is apparent from FIGS. 2 and 3, the inclination angle of the document support portion 11 with respect to the placement surface G is smaller in the booklet reading position than in the normal reading position. Similarly, as is clear from FIGS. 2 and 3, the inclination angle of the reading transport path R2 with respect to the placement surface G is smaller in the booklet reading position than in the normal reading position. Similarly, the inclination angle of the straight line connecting the document nip position by the first conveying roller pair 16 (described later) and the document nip position by the second conveying roller pair 20 (described later) with respect to the loading surface G is smaller in the booklet reading position than in the normal reading position, as is clear from Figures 2 and 2.

[0031] An operation unit 7 consisting of a number of operation buttons including a power button is provided on the front surface of the device. A first discharge opening 75 is formed on the front surface of the device, through which the document is discharged via a reverse transport path R3 (described later). Reference numeral 4a denotes a discharge tray that supports the document discharged from the first discharge opening 75 in an inclined position. The discharge tray 4a forms the surface of the second unit 4 in the +Y direction.

[0032] Next, the configuration of the document transport path in the scanner 1 will be described with reference to Figures 2 and 3. The document to be fed is supported in an inclined position by the document support section 11. The symbol P indicates the document to be supported. When multiple documents are supported on the document support section 11, the topmost document is sent downstream by a feed roller 14. The document support section 11 is formed in an upper opening / closing section 10. The upper opening / closing section 10 is rotatable about a rotation axis (not shown), and opens and closes a feed port 13 by rotating. Figure 1 shows the upper opening / closing section 10 in a closed state, and Figures 2 and 3 show the upper opening / closing section 10 in an open state. The upper opening / closing section 10 constitutes a first unit 3.

[0033] The document support section 11 is provided with a pair of edge guides 12 that guide the side edges of the document. The pair of edge guides 12 are provided so as to be slidable in the document width direction (X-axis direction). The pair of edge guides 12 are provided so as to be linked by a rack and pinion mechanism (not shown) so as to be spaced apart from each other or approach each other across the center position in the document width direction. That is, the scanner 1 employs a so-called center feeding method.

[0034] The feed roller 14 is provided in the second unit 4. The feed roller 14 rotates by receiving power from a motor (not shown). A separation roller 15 is provided in the first unit 3 at a position facing the feed roller 14. A rotation torque is applied to the separation roller 15 by a torque limiter (not shown) to prevent double feeding of documents. The feed roller 14 and separation roller 15 are provided at the center position in the document width direction. 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 topmost document is fed first, but the feed roller 14 may be provided below the documents placed on the document support section 11, and the bottommost document is fed first.

[0035] A first transport roller pair 16 is provided downstream of the feed roller 14 and the separation roller 15. The first transport roller pair 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 advance and retreat relative to 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 are rotated by power from a motor (not shown). The first lower roller 17 and the first upper roller 18 are provided in pairs so as to sandwich the center position in the document width direction. 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.

[0036] 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 surface) of the document supported by the document support unit 11, and the second reading unit 33 reads the top surface (second surface) of the document supported by the document support unit 11. The second reading unit 33 is provided so as to be movable forward and backward with respect to the first reading unit 32, and is pressed toward the first reading unit 32 by a pressing member (not shown), such as 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 constitutes the first reading unit 32, and reference numeral 33a denotes a contact glass that constitutes the second reading unit 33.

[0037] A second transport roller pair 20 is provided downstream of the first reading unit 32 and the second reading unit 33. The second transport roller pair 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 advance and retreat relative to 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 motor (not shown). The second lower roller 21 and the second upper roller 22 are provided in pairs so as to sandwich the center position in the document width direction. 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.

[0038] 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. The dashed line indicated by the symbol R2 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, and is an example of the first transport path.

[0039] When the device body 2 is in the normal reading position shown in Fig. 2, a reverse conveying path R3 is formed downstream of the reading conveying path R2 for reversing the read document upward and discharging it. The reverse conveying path R3 is a document conveying path from the nip position of the second conveying roller pair 20 to the nip position of the fourth conveying roller pair 28, and is a document conveying path for curving and reversing a document conveyed diagonally downward as shown by the two-dot chain line in Fig. 2 and discharging it diagonally upward from the first discharge port 75. In this embodiment, the reverse conveying path R3 is configured as a reverse path that reverses the conveyed document upward in its entirety, but it may further include, for example, a linear conveying path, and the reverse path that reverses the document upward may constitute a part of the reverse conveying path R3.

[0040] When the device body 2 is in the booklet reading position shown in Fig. 3, a non-reversing conveying path R4 is formed downstream of the reading conveying path R2 for discharging a read document without reversing it. The non-reversing conveying path R4 is a document conveying path downstream of the nip position of the second conveying roller pair 20, and is a document conveying path for discharging a document conveyed diagonally downward on the reading conveying path R2 from the second discharge opening 76 as shown by the two-dot chain line in Fig. 3 in a diagonally downward direction without curving and reversing the document. The second transport roller pair 20 functions as a discharge roller pair that discharges the document from the non-reverse transport path R4.

[0041] The outside of the reversing conveying path R3 is formed by a rotatable flap 34. The flap 34 switches its position by rotating around a flap rotation axis 34a. When the device body 2 is in the normal reading position, the flap 34 takes a first conveying path connecting position (FIG. 2) that connects the reversing conveying path R3 to the reading conveying path R2. When the device body 2 is in the booklet reading position, the flap 34 takes a second conveying path connecting position (FIG. 3) that connects the non-reversing conveying path R4 to the reading conveying path R2. The position of the flap 34 is changed by a solenoid (not shown). However, the position of the flap 34 may be changed by an external force applied by the user.

[0042] 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 driving 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 advance and retreat relative to the third driving roller 25, and is pressed toward the third driving roller 25 by a double torsion spring 55, which will be described later. The third driving roller 25 is driven by a motor (not shown). The third driven roller 26 is a roller that is rotated by the rotation of the third driving roller 25.

[0043] The fourth conveying roller pair 28 is composed of a fourth driving 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 forward and backward with respect to the fourth driving roller 29, and is pressed toward the fourth driving roller 29 by a double torsion spring 55 described later. The fourth driving roller 29 is driven by a motor (not shown). The fourth driven roller 30 is a roller that rotates following the rotation of the fourth driving roller 29. The fourth driving roller 29 is an example of a discharge driving roller, and the fourth driven roller 30 is an example of a discharge driven roller. The third driving roller 25 is an example of a transport driving roller provided upstream of the fourth transport roller pair 28, and the third driven roller 26 is an example of a transport driven roller provided upstream of the fourth transport roller pair 28.

[0044] Next, the medium ejection device 50 will be described. 4, the medium discharge device 50 includes a fourth drive roller 29 that contacts a first side of the document to be discharged, and a fourth driven roller 30 that contacts a second side opposite to the first side of the document to be discharged. The fourth drive roller 29 is an example of a discharge drive roller, and the fourth driven roller 30 is an example of a discharge driven roller. The fourth drive roller 29 and the fourth driven roller 30 are located below the discharge tray 4a, and discharge the document diagonally upward (in the direction of arrow B) with the second side of the document facing down. The medium discharge device 50 also includes the discharge tray 4a.

[0045] Here, the problem when discharging the document will be described. Reference symbol P indicates the document to be discharged, with the solid line indicating the posture of the document at the center position in the width direction and the two-dot chain line indicating the posture of the document at the side edge position in the width direction. Reference symbol Pe1 indicates the rear end of the document at the center position in the width direction, and reference symbol Pe2 indicates the rear end of the document at the side edge position in the width direction. Reference symbol 43 indicates a first discharge auxiliary member that imparts a kick-out effect to the vicinity of the center position in the width direction of the rear end of the document, that is, an effect of kicking out the rear end of the document in the direction of arrow B. The first discharge auxiliary member 43 is provided integrally with the fourth driven roller 30 and rotates together with the fourth driven roller 30.

[0046] The first discharge assist member 43 provides a kick-out effect to the original document trailing end Pe1, so that the original document trailing end Pe1 is prevented from remaining on the fourth driven roller 30. However, if only the first discharge assist member 43 is provided, the original document trailing end Pe2 cannot be provided with the kick-out effect, and the original document trailing end Pe2 is likely to remain on the fourth driven roller 30 as shown in FIG. 4. If the next original document is discharged in this state, the stacking state of the original documents on the discharge tray 4a will be disturbed. This type of problem is particularly likely to occur if the original document trailing end Pe2 is curled.

[0047] In view of the above problems, the medium discharge device 50 according to this embodiment has the following configuration. In Figures 5 and 6, the medium discharge device 50 has a first discharge assist member 43 which is a member that comes into contact with the second side of the document to be discharged, has a larger diameter than the fourth driven roller 30, and rotates by receiving torque from the fourth driven roller 30, and a second discharge assist member 45 which is a member that comes into contact with the second side of the medium to be discharged, has a larger diameter than the fourth driven roller 30, and rotates by receiving torque from the fourth driven roller 30.

[0048] The second discharge auxiliary member 45 is disposed outward of the first discharge auxiliary member 43 in the width direction (X-axis direction) intersecting the medium discharge direction (direction B in FIG. 4). The fourth driven roller 30 and the first discharge auxiliary member 43 are provided so as to be displaceable in the direction toward and away from the fourth driving roller 29 (direction C in FIG. 5), and the torque of the fourth driven roller 30 is transmitted to the second discharge auxiliary member 45 via the shaft 46 and the first universal joint 51.

[0049] As a result, a kick-out effect can be imparted to the side edge of the rear end of the document or its vicinity by the second discharge auxiliary member 45. And, because the power of the fourth driven roller 30 is transmitted to the second discharge auxiliary member 45 via the shaft 46 and the first universal joint 51, even if the fourth driven roller 30 is displaced, the second discharge auxiliary member 45 can easily maintain its position relative to the document (position in the C direction). Therefore, a kick-out effect can be imparted to the side edge of the rear end of the document or its vicinity without being affected by the displacement of the fourth driven roller 30.

[0050] Further explanation is given below. In this embodiment, the first discharge assist member 43 and the second discharge assist member 45 are made of a cylindrical elastic member, for example, a sponge. However, this is not limiting and other elastic members may be used. Such an elastic member can provide an appropriate kick-out effect to the rear end of the document.

[0051] 5, the line indicated by the symbol CL is a line passing through the center position of the document in the width direction and is a center line along the document discharge direction, and the fourth driving roller 29, the fourth driven roller 30, the first discharge assist member 43, the second discharge assist member 45, and further the first universal joint 51, the shaft 46, the first bearing portion 40, and the second bearing portion 41, which will be described later, are provided at positions that are line-symmetrical with respect to the center line CL. This makes it possible to apply a kick-out force evenly to the rear end of the document along the width direction.

[0052] In addition, in this embodiment, the width of the second discharge auxiliary member 45 in the X-axis direction is formed larger than the width of the first discharge auxiliary member 43, thereby enabling an appropriate kick-out effect to be imparted to the side edge of the rear end of the document or its vicinity. However, the width of the second ejection auxiliary member 45 may be the same as the width of the first ejection auxiliary member 43 , or the width of the second ejection auxiliary member 45 may be smaller than the width of the first ejection auxiliary member 43 .

[0053] Reference numeral 47 denotes a driven roller shaft common to the two fourth driven rollers 30, and this driven roller shaft 47 is journaled by the first bearing portion 40. In this embodiment, the driven roller shaft 47 does not rotate relative to the first bearing portion 40, and the fourth driven roller 30 rotates relative to the driven roller shaft 47. As shown in Fig. 7, a long groove 40a is formed in the first bearing portion 40, and a regulating portion 40b is formed in the long groove 40a, so that the displacement of the driven roller shaft 47 in the direction of advancing into the discharge tray 4a is regulated by the abutment of the regulating portion 40b.

[0054] That is, the restricting portion 40b restricts the displacement of the fourth driven roller 30 in the direction advancing to the discharge tray 4a. This provides the following advantageous effects. If the first discharge assisting member 43, which displaces together with the fourth driven roller 30, comes into contact with the document sheets supported on the discharge tray 4a, the stacked state of the documents on the discharge tray 4a may be disturbed. However, since the restricting portion 40b restricts the displacement of the first discharge assisting member 43 in the direction advancing to the discharge tray 4a as described above, it is possible to prevent the first discharge assisting member 43 from coming into contact with the document sheets supported on the discharge tray 4a, and it is possible to properly maintain the stacked state of the documents on the discharge tray 4a.

[0055] The fourth driven roller 30 transmits power to the first universal joint 51. The first universal joint 51 is connected to a shaft 46, and is configured so that power is transmitted from the first universal joint 51 to the shaft 46 even if the attitude of the shaft 46 with respect to the first universal joint 51 changes. An end portion 46a of the shaft 46 is supported by a second bearing portion 41. The second bearing portion 41 supports the shaft 46 so as to allow the attitude of the shaft 46 to change. A second discharge auxiliary member 45 is provided on the shaft 46. In this way, the shaft 46 is supported by the second bearing portion 41, which is located outside the second discharge auxiliary member 45 in the width direction, so that the second discharge auxiliary member 45 can appropriately maintain its position relative to the document (position in direction C in Figure 5) when the fourth driven roller 30 is displaced. In addition, in Fig. 5, line Lk is the axial center line of driven roller shaft 47. When the fourth driven roller 30 and first discharge assist member 43 are displaced upward in Fig. 5 in accordance with the thickness of the document, shaft 46 tilts with respect to line Lk as shown in Fig. 11, causing second discharge assist member 45 to also tilt, but the position in direction C is substantially maintained.

[0056] 8, 9, and 10, the driven roller shaft 47 is pressed toward the fourth drive roller 29 by a double torsion spring 55. The double torsion spring 55 includes a coil portion 55a, a first arm portion 55b, and a second arm portion 55c, and the driven roller shaft 47 is pressed by the first arm portion 55b. In addition, the second arm portion 55 c presses the rotation shaft 49 of the third driven roller 26 towards the third driving roller 25 . In this manner, the fourth driven roller 30 and the third driven roller 26 are pressed against the opposing rollers by the double torsion spring 55, making it possible to reduce the number of parts and the number of assembly steps.

[0057] Next, another embodiment will be described with reference to Fig. 12. This embodiment differs from the embodiment described with reference to Figs. 5 to 11 in that a second universal joint 52 is provided. That is, in this embodiment, two universal joints, a first universal joint 51 and a second universal joint 52, are provided between the fourth driven roller 30 and the second discharge assist member 45. According to this embodiment, it is possible to prevent the second discharge assist member 45 from tilting together with the shaft 46 when the fourth driven roller 30 is displaced, and it is possible to maintain not only the position but also the posture relative to the document. The number of universal joints is not limited to two, but may be three or more.

[0058] Next, still another embodiment will be described with reference to Fig. 13. This embodiment differs from the embodiment described with reference to Figs. 5 to 11 in the form of the first and second ejection auxiliary members, and in this embodiment, a first ejection auxiliary member 58 is provided instead of the above-mentioned first ejection auxiliary member 43, and a second ejection auxiliary member 59 is provided instead of the above-mentioned second ejection auxiliary member 45. The first ejection auxiliary member 58 has a plurality of first projections 58a at equal intervals along the circumferential direction, and the second ejection auxiliary member 45 has a plurality of second projections 59a at equal intervals along the circumferential direction. The first ejection auxiliary member 58 and the second ejection auxiliary member 45 can be formed of an elastic member such as sponge or rubber, or can be formed of a resin material. In this way, the first ejection assist member 58 has multiple first protrusions 58a along the circumferential direction, and the second ejection assist member 45 has multiple second protrusions 59a along the circumferential direction, so that an appropriate kick-out effect can be imparted to the rear end of the document.

[0059] In this embodiment, the number of the first protrusions 58a and the second protrusions 59a is the same, but may be different. In this embodiment, the phases of the first protrusions 58a and the second protrusions 59a are the same, but may be different. In this embodiment, the phases of the first protrusions 58a provided on one side of the center line CL in the width direction (see FIG. 5) and the first protrusions 58a provided on the other side are the same. In this embodiment, the phases of the second protrusions 59a provided on one side of the center line CL in the width direction (see FIG. 5) and the second protrusions 59a provided on the other side are the same.

[0060] Next, quick-drying lubricants and non-quick-drying lubricants will be described with reference to FIGS. 14, the fourth driven roller 30 is integrally formed with a roller body 30a and a flange 30b. The fourth driven roller 30 is made of, for example, POM (polyoxymethylene). The first discharge assistant member 43 is provided on the flange 30b.

[0061] The fourth driven roller 30 has a shaft hole 30c through which a driven roller shaft 47 passes. As described above, since the driven roller shaft 47 does not rotate and the fourth driven roller 30 rotates relative to the driven roller shaft 47, the inner peripheral surface of the shaft hole 30c and the outer peripheral surface of the driven roller shaft 47 slide with the rotation of the fourth driven roller 30. Therefore, a quick-drying lubricant Gr is used between the inner peripheral surface of the shaft hole 30c and the outer peripheral surface of the driven roller shaft 47, as shown by the dashed line.

[0062] In this specification, a lubricant having quick-drying properties means a lubricant that quickly forms a lubricating film on an object to be coated when applied to the object, has no fluidity after the lubricating film is formed, and hardly flows even when an external force is applied. As an example of the quick-drying lubricant Gr, a volatile solvent containing a lubricating component can be used, for example, a fluorine-based solvent containing a lubricating component can be used. When such a quick-drying lubricant Gr is applied to an object to be coated, the solvent quickly volatilizes and a lubricating film is formed on the object to be coated. Examples of the lubricating component include PTFE (polytetrafluoroethylene) powder.

[0063] In this specification, a lubricant that does not have quick-drying properties, i.e., a non-quick-drying lubricant, means a lubricant that has fluidity when the device is used after being applied to the object to be coated, and in particular, a lubricant that can adhere to the medium being transported due to its fluidity. Examples of non-quick-drying lubricants include lubricating oils in which additives are added to a base oil, and greases in which a thickener is further added to the base oil.

[0064] In a configuration in which the fourth driven roller 30 has an axle hole 30c through which the driven roller shaft 47 passes, and the inner peripheral surface of the axle hole 30c and the outer peripheral surface of the driven roller shaft 47 slide against each other as the fourth driven roller 30 rotates, if a non-quick-drying lubricant is used as a lubricant between the inner peripheral surface of the axle hole 30c and the outer peripheral surface of the driven roller shaft 47, some of the lubricant may move to the first discharge assist member 43 and adhere to the document, causing damage to the document. In particular, since the first discharge assist member 43 is made of a sponge, which is an example of an elastic material, the first discharge assist member 43 has a tendency to absorb the lubricant, which then adheres to the document, causing damage. In this embodiment, after applying a lubricant to the outer peripheral surface of the driven roller shaft 47, the fourth driven roller 30 is fitted to the driven roller shaft 47 in the +X direction. As a result, when a non-quick-drying lubricant is used as the lubricant, the flange portion 30b moves the excess of the non-quick-drying lubricant to the first bearing portion 40 side, and accumulates between the flange portion 30b and the first bearing portion 40. If the non-quick-drying lubricant accumulates between the flange portion 30b and the first bearing portion 40, there is a risk that the non-quick-drying lubricant will move to the first discharge auxiliary member 43 as the fourth driven roller 30 rotates.

[0065] However, as described above, since the quick-drying lubricant Gr is used as a lubricant between the inner surface of the shaft hole 30c and the outer surface of the driven roller shaft 47, the lubricant can be prevented from migrating to the first discharge auxiliary member 43, and the lubricant can be prevented from adhering to the document and damaging the document.

[0066] In this embodiment, the fourth driven roller 30 has a flange portion 30b, and the first discharge assistant member 43 is provided on the flange portion 30b. In this configuration, when a lubricant is interposed between the inner surface of the shaft hole 30c and the outer surface of the driven roller shaft 47, some of the lubricant is likely to move to the first discharge auxiliary member 43 and cause damage to the original document. However, since the quick-drying lubricant Gr is used as the lubricant as described above, it is possible to prevent the lubricant from adhering to the original document and causing damage to the original document.

[0067] In this embodiment, the first discharge assisting member 43 is made of sponge, which is an example of an elastic material, so that the rear end of the document can be suitably pushed out in the discharge direction. Here, if the first discharge assisting member 43 is formed of an elastic material, the first discharge assisting member 43 will absorb the lubricant and adhere to the document, easily causing damage to the document; however, since the quick-drying lubricant Gr is used as the lubricant as described above, it is possible to prevent the lubricant from adhering to the document and causing damage to the document.

[0068] 13, when the first discharge assisting member 58 is used instead of the first discharge assisting member 43, the first discharge assisting member 58 has a plurality of first protrusions 58a along the circumferential direction on the outer periphery. With this configuration, the rear end of the document can be appropriately sent out in the discharge direction. Furthermore, in such a configuration, the first protrusion 58a may be pressed strongly against the document, and when the first discharge assist member 58 absorbs the lubricant, the lubricant is likely to adhere to the document from the first protrusion 58a, i.e., the document is likely to be soiled. However, since the quick-drying lubricant Gr is used as the lubricant as described above, it is possible to prevent the lubricant from adhering to the document and causing the document to become soiled.

[0069] 15, the present embodiment includes a driving roller shaft 29a which is a rotation shaft of the fourth driving roller 29, and a regulating portion 5a which regulates the deflection of the driving roller shaft 29a, and a fast-drying lubricant Gr is applied to a position on the outer circumferential surface of the driving roller shaft 29a which faces the regulating portion 5a. The regulating portion 5a is provided in the third unit 5, and by providing the regulating portion 5a at a position which faces the outer circumferential surface of the driving roller shaft 29a, the deflection of the driving roller shaft 29a caused by the fourth driven roller 30 pressing against the fourth driving roller 29 is regulated.

[0070] Here, when a quick-drying lubricant Gr is applied to the outer peripheral surface of the drive roller shaft 29a, specifically the area facing the regulating portion 5a as shown by the arrow Ha, the increase in the rotational load of the drive roller shaft 29a when the drive roller shaft 29a abuts against the regulating portion 5a can be suppressed. Here, since the outer peripheral surface of the drive roller shaft 29a faces the first discharge auxiliary member 43, if a lubricant is applied to the outer peripheral surface of the drive roller shaft 29a, there is a risk that some of this lubricant will move to the first discharge auxiliary member 43 and adhere to the document, thereby causing damage to the document. However, since the quick-drying lubricant Gr is used as the lubricant as described above, the lubricant can be prevented from moving to the first discharge assist member 43, and the lubricant can be prevented from adhering to the document and damaging the document.

[0071] If the driven roller shaft 47 has sliding parts at other parts in addition to the part facing the inner circumferential surface of the shaft hole 30c, the non-quick-drying lubricant may be used at these sliding parts. Alternatively, the quick-drying lubricant Gr may be used at all of the sliding parts. Similarly, if the drive roller shaft 29a has sliding parts at other locations in addition to the position indicated by the arrow Ha in FIG. 15, a non-quick-drying lubricant may be used at these sliding parts, or the quick-drying lubricant Gr may be used at all sliding parts, including the position indicated by the arrow Ha in FIG. 15. Alternatively, when a component other than the driven roller shaft 47 or the driving roller shaft 29a has a sliding part, the quick-drying lubricant Gr may be used for the sliding part. For example, the first bearing part 40 and the second bearing part 41 may be used with the quick-drying lubricant Gr.

[0072] 12, in a configuration including two universal joints, the first universal joint 51 and the second universal joint 52, and the second discharge assist member 45 being provided adjacent to the second universal joint 52, if a lubricant is applied to the second universal joint 52, a part of the lubricant is likely to move to the second discharge assist member 45 and easily soil the document. In this configuration, therefore, by using a quick-drying lubricant Gr for the second universal joint 52, it is possible to prevent the lubricant from moving from the second universal joint 52 to the second discharge assist member 45, and to prevent the lubricant from adhering to the document and soiling the document.

[0073] 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. For example, in each of the above embodiments, an example in which the medium ejection device is applied to an image reading device has been described, but the medium ejection device may also be applied to a recording device that records on a medium. An example of a recording device is an inkjet printer equipped with a recording head that ejects ink onto a medium. In each of the above embodiments, for example, a recording device can be configured by providing a recording head instead of the second reading unit 33. [Explanation of symbols]

[0074] DESCRIPTION OF SYMBOLS 1...scanner, 2...device main body, 3...first unit, 4...second unit, 4a...output tray, 5...third unit, 6...main body support section, 7...operation section, 8a...lock release section, 10...upper opening / closing section, 11...original support section, 12...edge guide, 13...feed port, 14...feed roller, 15...separation roller, 16...first transport roller pair, 17...first lower roller, 18...first upper roller, 20...second transport roller pair, 21...second lower roller, 22...second upper roller, 24...third transport roller pair, 25...third drive roller, 26...third driven roller, 28...fourth transport roller pair, 29...fourth drive roller, 29a...drive roller shaft , 30...fourth driven roller, 32...first reading unit, 32a...contact glass, 33...second reading unit, 33a...contact glass, 34...flap, 34a...flap rotation shaft, 40...first bearing unit, 40a...long groove, 40b...regulation unit, 41...second bearing unit, 43...first discharge auxiliary member, 45...second discharge auxiliary member, 46...shaft, 47...driven roller shaft, 49...rotation shaft, 50...medium discharge device, 51...first universal joint, 52...second universal joint, 55...double torsion spring, 55a...coil unit, 55b...first arm unit, 55c...second arm unit, 58...first discharge auxiliary member, 58a...first protrusion, 59...second discharge auxiliary member, 59a...second protrusion, Gr...Quick-drying lubricant, R1: Document feed path, R2: Scanning path, R3: Reversing path, R4: Non-reversing path

Claims

1. a discharge drive roller that is in contact with a first surface of the medium to be discharged and that rotates by receiving power from a drive source; a discharge driven roller that is in contact with a second surface of the medium to be discharged, the second surface being opposite to the first surface, and that is driven to rotate while nipping the medium between the discharge driven roller and the discharge drive roller; a driven roller shaft which is a rotation shaft of the discharge driven roller; a discharge auxiliary member that is in contact with the second surface of the medium to be discharged, the discharge auxiliary member having a larger diameter than the discharge driven roller and rotating integrally with the discharge driven roller; Equipped with The discharge driven roller has a shaft hole through which the driven roller shaft passes, As the discharge driven roller rotates, the inner circumferential surface of the shaft hole and the outer circumferential surface of the driven roller shaft slide against each other, A quick-drying lubricant is used between the inner peripheral surface of the shaft hole and the outer peripheral surface of the driven roller shaft. A medium ejection device.

2. 2. The medium ejection device according to claim 1, The discharge driven roller has a flange portion, The discharge auxiliary member is provided on the flange portion. A medium ejection device.

3. 2. The medium ejection device according to claim 1, The discharge assistance member is made of an elastic material. A medium ejection device.

4. 4. The medium ejection device according to claim 3, The discharge auxiliary member has a plurality of protrusions on an outer periphery along a circumferential direction. A medium ejection device.

5. 2. The medium ejection device according to claim 1, A drive roller shaft which is a rotation shaft of the discharge drive roller; A regulating portion that regulates the deflection of the drive roller shaft; Equipped with The quick-drying lubricant is applied to a position on the outer circumferential surface of the driving roller shaft that faces the regulating portion. A medium ejection device.

6. 2. The medium ejection device according to claim 1, The driven roller shaft has a sliding portion at another portion in addition to a portion facing the inner circumferential surface of the shaft hole, A non-quick-drying lubricant is used in the sliding portion. A medium ejection device.

7. 2. The medium ejection device according to claim 1, the discharge auxiliary member is a first discharge auxiliary member, the second discharge auxiliary member being a member that contacts the second surface of the medium to be discharged, the second discharge auxiliary member having a larger diameter than the discharge driven roller, and rotating integrally with the discharge driven roller; the second discharge auxiliary member is disposed outside the first discharge auxiliary member in a width direction intersecting with a medium discharge direction, the discharge driven roller and the first discharge auxiliary member are provided so as to be displaceable in a direction toward and away from the discharge driving roller, The torque of the discharge driven roller is transmitted to the second discharge auxiliary member via a shaft and a universal joint. A medium ejection device.

8. The medium ejection device according to claim 7, the universal joint is a first universal joint, and the first universal joint and a second universal joint are provided between the discharge driven roller and the second discharge auxiliary member, the second universal joint being positioned outside the first universal joint in the width direction, The second discharge auxiliary member is provided at a position adjacent to the second universal joint in the width direction, The fast-drying lubricant is used in the second universal joint. A medium ejection device.

9. The medium ejection device according to any one of claims 1 to 8; a reading unit that is located upstream of the medium ejection device in a medium transport path and that reads the medium; An image reading device comprising:

Images