Medium detection device and electronic apparatus

Abstract

To reduce a risk that an end 36 of a medium 2 and surface parts 47, 48 continuing to the end 36 are deformed by reaction force of a lever 31.SOLUTION: The medium detection device 23 includes a lever 31 that is disposed in the transport path 8 and is movable by coming into contact with the medium 2 transported in the transport direction along the transport path, and a sensor 32 that detects the medium based on the movement of the lever. The lever 31 includes an end-portion contact portion 34 having a long sliding surface 37 with which an end portion 36 in a transport direction of the media transported along the transport path comes into contact and slides, and a wide surface portion 35 provided in the end-portion contact portion 34 and having a wide surface 38 having a widthwise size W1 larger than a widthwise size W2 of the end-portion contact portion 34 in a widthwise direction intersecting the transport direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a medium detection device and an electronic device. [Background technology]

[0002] An example of a conventional device of this type is described in Patent Document 1. Patent document 1 discloses that the media detection mechanism includes a detection lever that is pushed and moved when it comes into contact with the end of the transported media, and a detector that detects the presence or absence of the media in accordance with the displacement caused by the movement of the detection lever. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-166892 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, the detection lever has a narrow width to accurately detect the position of the transported medium. When the detection lever has a narrow width, the area where the edge of the medium comes into contact with the detection lever is concentrated within the narrow area of ​​the narrow width. In other words, the reaction force that the edge of the medium receives from the detection lever is concentrated within the narrow area of ​​the narrow width. Therefore, when transporting low-rigidity media, in other words, media with a weak stiffness, the edge of the medium and the surface portion connected to the edge may be deformed by the reaction force. Furthermore, when transporting a medium with holes, such as loose-leaf paper, the edge of the medium first abuts against the detection lever, displacing the detection lever and detecting the medium. As the medium continues to be transported, the tip of the detection lever follows the surface of the medium and comes into contact with it. At this time, because the detection lever is narrow, the tip may fall into the hole in the medium. If the detection lever falls into the hole in the medium, the detection lever returns to its original position and is removed from the detector. This can result in erroneous detection of the medium's position and size. Therefore, it is possible to prevent the media from falling through the hole by making the width of the detection lever larger than the diameter of the hole in the media. However, simply increasing the width of the detection lever makes the contact point with the edge of the media unstable, which reduces the accuracy of detecting the media position, etc. [Means for solving the problem]

[0005] In order to solve the above problem, the media detection device of the present invention comprises a lever that is arranged on a transport path and is movable by contact with a medium transported in a transport direction along the transport path, and a sensor that detects the medium based on the movement of the lever, wherein the lever comprises an end contact portion having a long sliding surface that contacts and slides with the end of the medium in the transport direction transported along the transport path, and a wide surface portion that is provided on the end contact portion and has a wide surface with a width dimension larger than the width dimension of the end contact portion in a width direction that intersects the transport direction, and the sliding surface protrudes from the wide surface so that the end of the medium being transported comes into contact first.

[0006] In addition, the electronic device of the present invention is characterized by comprising a media detection device of any one of the first to eighth aspects described below, a media transport unit that transports the media along the transport path, and a processing unit that performs processing on the transported media. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a cross-sectional side view of a main part corresponding to the medium detection device and the image reading device of the first embodiment. [Figure 2] 2 is an enlarged side cross-sectional view and a partially enlarged view of the main part of FIG. 1. [Figure 3] FIG. 1 is a perspective view of a medium detection device according to a first embodiment. [Figure 4] FIG. 10 is a perspective view of a medium detection device according to a second embodiment. [Figure 5] FIG. 10 is a perspective view of a medium detection device according to a third embodiment. [Figure 6] FIG. 10 is a schematic diagram illustrating how to determine the amount of protrusion from the wide surface of the sliding surface. [Figure 7] FIG. 10 is a schematic diagram illustrating how to determine the amount of protrusion from the wide surface of the sliding surface. DETAILED DESCRIPTION OF THE INVENTION

[0008] The present invention will now be briefly described. In order to solve the above problem, a media detection device according to a first aspect of the present invention comprises a lever that is arranged on a transport path and that can move by coming into contact with a medium transported in a transport direction along the transport path, and a sensor that detects the medium based on the movement of the lever, wherein the lever comprises an end contact portion having a long sliding surface that contacts and slides with the end of the medium in the transport direction transported along the transport path, and a wide surface portion that is provided on the end contact portion and has a wide surface with a width dimension larger than the width dimension of the end contact portion in a width direction that intersects the transport direction, and the sliding surface protrudes from the wide surface so that the end of the medium being transported comes into contact first.

[0009] According to this aspect, the lever includes an end contact portion having a long sliding surface that contacts and slides with an end portion in the transport direction of the medium transported along the transport path, and a wide surface portion that is provided on the end contact portion and has a wide surface with a width dimension larger than the width dimension of the end contact portion in a width direction that intersects the transport direction. Furthermore, the lever protrudes from the wide surface so that the sliding surface comes into contact first with the end portion of the medium being transported. (1) As a result, the edge of the medium being transported contacts the sliding surface of the narrow end contact portion protruding from the wide surface first. Because the sliding surface is long, when the edge of the medium contacts the sliding surface and the lever begins to move, the portion of the edge of the medium that contacts the sliding surface slides while maintaining contact with the sliding surface and proceeds in the transport direction. As the medium proceeds in the transport direction, the contact position with the sliding surface gradually and continuously shifts from the edge toward the surface. Accordingly, the medium begins to bend concavely, starting from the contact point with the sliding surface. That is, other surface portions in the width direction of the medium that are connected to the portion of the surface portion that contacts the sliding surface on the leading edge side in the transport direction of the medium begin to approach the wide surface. The degree to which the surface portion approaches the wide surface of the medium varies depending on the rigidity of the medium. A medium with high rigidity is often transported with its surface portion in contact only with the sliding surface and not with the wide surface. On the other hand, a medium with low rigidity is often transported with its surface portion in contact with both the sliding surface and the wide surface. In other words, low-rigidity media receive the reaction force of the lever at both the portion of the media that contacts the sliding surface and the portion that contacts the wide surface. This prevents the reaction force from being concentrated on the narrow sliding surface, as in the past, thereby reducing the risk of the edge of the media and the surface portion connected to that edge being deformed by the reaction force. Furthermore, it is possible to narrow the width of the sliding surface that contacts the edge of the media, allowing the lever to accurately detect the position of the media being transported. The amount of protrusion of the sliding surface from the wide surface is set based on the type of medium expected to be transported and the degree of rigidity of each medium.

[0010] (2) Furthermore, when transporting a medium with holes formed therein, such as loose-leaf paper, as described above, the contact position with the sliding surface gradually and continuously shifts from the edge toward the surface as the medium advances in the transport direction. In this case, if the position of the edge contact portion and the hole are aligned in the transport direction, when the leading edge of the medium passes the contact position with the sliding surface, the leading edge of the edge contact portion is likely to fall into the hole. However, in this embodiment, the presence of the wide surface portion reduces the risk of the medium falling into the hole. Here, it is preferable that the width dimension of the wide surface portion be set larger than the size of the hole.

[0011] A media detection device according to a second aspect of the present invention is an aspect dependent on the first aspect, and is characterized in that the lever is rotatable with the shaft portion as a pivot point, with the end contact portion and the wide surface portion acting as free ends, and when the end contact portion has fully rotated due to contact with the media during transport, the tip portion of the wide surface portion comes into contact with the surface of the media.

[0012] According to this aspect, the lever is rotatable with the shaft serving as a pivot point, with the end contact portion and the wide surface portion serving as free ends. Furthermore, the lever is configured so that when the end contact portion has fully rotated due to contact with the medium during transport, the tip of the wide surface portion comes into contact with the surface of the medium. Here, the phrase "a state in which the end contact portion has fully rotated" refers to a state in which the end of the medium has slid past the sliding surface of the end contact portion and the lever has reached its upper limit of rotation. In other words, when the end of the medium passes the position of the sliding surface and the lever has fully rotated, the tip of the wide surface portion is configured to come into contact with the surface of the medium, so the subsequent transport state of the medium is more stable than when the medium is transported in contact with only the end contact portion.

[0013] A medium detection device according to a third aspect of the present invention is an aspect dependent on the second aspect, characterized in that the sliding surface is inclined with respect to the wide surface, and the amount of protrusion of the sliding surface from the wide surface is greater on the side closer to the shaft portion and smaller on the side farther from the shaft portion.

[0014] According to this aspect, the sliding surface is inclined relative to the wide surface, and the amount of protrusion of the sliding surface from the wide surface is greater on the side closer to the shaft portion and smaller on the side farther from the shaft portion, thereby making it possible to obtain the effect of the first aspect more effectively than in a structure in which the sliding surface is not inclined relative to the wide surface.

[0015] A medium sensing device according to a fourth aspect of the present invention is an aspect dependent on the first aspect, and is characterized in that the width dimension of the wide surface is greater than 8.5 mm. This aspect can also be subordinate to the second or third aspect.

[0016] According to this aspect, the width of the wide surface is greater than 8.5 mm, which reduces the risk of the paper falling into the holes of ordinary loose-leaf paper.

[0017] A media detection device according to a fifth aspect of the present invention is an aspect dependent on the first aspect, characterized in that the lever is movable in the forward and reverse directions of the conveying direction, and the end contact portion and the wide surface portion are provided on both the surface facing the forward direction and the surface facing the reverse direction, respectively. This aspect can also be subordinate to any one of the second to fourth aspects.

[0018] According to this aspect, the lever is movable in the forward and reverse directions of the transport direction, and the end contact portion and the wide surface portion are provided on both the surface facing the forward direction and the surface facing the reverse direction, respectively. This makes it possible to obtain the effect of the first aspect for transport in both directions, whether the medium is transported in the forward direction or the reverse direction relative to the end contact portion.

[0019] A media detection device according to a sixth aspect of the present invention is an aspect dependent on the first aspect, and is characterized in that the end contact portion is positioned in the center of the width direction of the transport path along which the media is transported, the width direction intersecting the transport direction. This aspect can also be subordinate to any one of the second to fifth aspects.

[0020] According to this aspect, the edge contact portion is configured to be located at the center of the width direction of the transport path along which the medium is transported, which crosses the transport direction. In other words, since the center of the width of the medium comes into contact with the edge contact portion, the accuracy of detecting the presence or absence of the medium can be improved.

[0021] A seventh aspect of the present invention is a medium detection device according to the second aspect, characterized in that the width of the wide surface portion gradually decreases from the tip end to the base end, i.e., the shape of the wide surface portion in a plan view is approximately triangular. This aspect can also be subordinate to any one of the third to sixth aspects.

[0022] According to this aspect, the width dimension of the wide surface portion is configured to gradually decrease from the tip portion to the base portion, thereby making it possible to suppress the increase in weight due to the provision of the wide surface portion compared to a case where the wide surface portion is substantially rectangular.

[0023] The media detection device according to the eighth aspect of the present invention is an aspect dependent on the second aspect, and is characterized in that the wide surface portion exists in a range extending from the position where the media being transported first comes into contact in the area where the end contact portion extends to the tip portion. This aspect can also be subordinate to any one of the third to sixth aspects. Here, in this specification, the "first contact position" in "the position where the medium being transported in the area where the end contact portion extends first contacts" does not have to be a position that is strictly determined to be a single point, but is used to mean a position that has a range taking into account the displacement of the leading edge position of the medium being transported, etc.

[0024] According to this aspect, the wide surface portion is configured to be present in a range extending from the position where the medium first comes into contact with the end contact portion in the region where the end contact portion extends to the tip portion, thereby making it possible to suppress an increase in weight due to the provision of the wide surface portion.

[0025] An electronic device according to a ninth aspect of the present invention is characterized in that it comprises a media detection device according to any one of the first to eighth aspects, a media transport unit that transports the media along the transport path, and a processing unit that performs processing on the transported media. According to this aspect, in an electronic device such as a recording device or an image reading device, it is possible to obtain the same effect as any one of the first to eighth aspects.

[0026] [Embodiment] A medium detection device according to an embodiment of the present invention and an image reading device including this medium detection device will be specifically described below with reference to FIGS. In the following explanation, the three mutually orthogonal axes are referred to as the X-axis, Y-axis, and Z-axis, as shown in each figure. The directions indicated by the arrows on the three axes (X, Y, Z) are the + directions of each axis, and the opposite directions are the - directions. The Z-axis direction corresponds to the vertical direction, i.e., the direction in which gravity acts, the +Z direction indicates a vertically upward direction, and the -Z direction indicates a vertically downward direction. The X-axis and Y-axis directions correspond to horizontal directions. The +Y direction indicates the front direction of the device, and the -Y direction indicates the rear direction of the device. The +X direction indicates the right direction of the device, and the -X direction indicates the left direction of the device.

[0027] <Overall overview of electronic device and media detection device> The electronic device of this embodiment is an image reading device, i.e., a scanner, capable of reading images on a medium. Here, the image refers to something visually recorded on the medium, such as text, figures, tables, pictures, photographs, etc. The medium is not limited to sheets, but also includes cards, booklets, etc. As shown in FIG. 1, the image reading device 1 of this embodiment includes a first reading unit 3 capable of reading an image on a medium 2, a medium feeding unit 4, and a medium transport unit 5. The first reading unit 3 is equipped with an image reading sensor (CIS: Contact Image Sensor) as a processing unit that performs image reading processing, and is elongated in the Y-axis direction. The image on the medium 2 being conveyed is read as it passes through the reading position of the CIS.

[0028] The medium feeding unit 4 includes a medium loading unit 6 and a feed roller 7. The medium 2 loaded on the medium loading unit 6 is fed in the transport direction F by the feed roller 7. The feed roller 7 is configured to be able to move toward and away from the medium 2 placed on the medium loading section 6. The feed roller 7 moves to a position where it comes into contact with the medium 2, and is rotated by power transmitted from a drive source (not shown), thereby feeding out the medium 2.

[0029] The medium transport unit 5 includes a feed roller pair 9, a first transport roller pair 10, a second transport roller pair 11, and a third transport roller pair 12, which are arranged along a transport path 8 along which the medium 2 is transported. In Figure 1, the transport path 8 is indicated by a two-dot chain line. The pair of feed rollers 9 is composed of a feed roller 13 and a separation roller 14. The feed roller 13 rotates by power transmitted from a drive source (not shown), and applies a feeding force to the medium 2 in the conveying direction F. When multiple sheets of medium 2 are fed, the separation roller 14 nips the medium 2 between itself and the feed roller 13, separating the sheets so that only one sheet of medium 2 in contact with the feed roller 13 is sent in the conveying direction F. The first transport roller pair 10 is made up of a drive roller 15 and a driven roller 16. The second transport roller pair 11 is made up of a drive roller 17 and a driven roller 18. The third transport roller pair 12 is made up of a drive roller 19 and a driven roller 20. Drive roller 15, drive roller 17, and drive roller 19 are all rotated by power transmitted from a drive source (not shown), and apply a feed force to medium 2 in the transport direction F.

[0030] In this embodiment, as shown in FIG. 1 , the transport path 8 has a curved path 21 that turns around in a substantially U-shape downstream of the first transport roller pair 10. Reference numeral 22 denotes a driven roller that is disposed on the curved path 21. The first reading unit 3 is disposed in an area that is downstream of the curved path 21 of the transport path 8 and upstream of the third transport roller pair 12. In this embodiment, the first reading unit 3 is disposed below the feed roller pair 9, i.e., the first and second transport roller pairs 12 are disposed so as to overlap each other in the Z direction. The third transport roller pair 12 is disposed below the medium loading unit 6. The third transport roller pair 12 is disposed below the feed roller 7, i.e., the third transport roller pair 12 are disposed so as to overlap each other in the Z direction. The second transport roller pair 11 is located in the area of ​​the curved path 21. A medium detection device 23 is disposed near the second transport roller pair 11. The medium detection device 23 is used to detect the position of the transported medium 2 on the transport path 8. The medium detection device 23 will be described in detail later.

[0031] The image reading device 1 of this embodiment includes a second reading unit 24. The second reading unit 24 is placed on a transparent glass table 25 and is used to read an image on a stationary medium 2. The second reading unit 24 is configured to read the image while moving along the surface of the stationary medium 2. The glass table 25 is configured so that the first reading unit 3, the medium feeding unit 4, the medium transport unit 5, and other components located above the glass table 25 can be rotated to expose them in their entirety. By placing the glass table 25 in the exposed state, the medium 2 can be placed on it.

[0032] [Embodiment 1] <Media detection device> The medium detection device 23 of the first embodiment will be described below with reference to FIGS. As described above, the medium detection device 23 of the first embodiment is disposed on the curved path 21 of the transport path 8. The medium detection device 23 includes a lever 31 that is movable by coming into contact with the medium 2 transported in the transport direction F along the transport path 8, and a sensor 32 that detects the passage of the medium 2 based on the movement of the lever 31. In this embodiment, the movement of the lever 31 is a rotational movement. The rotational structure of the lever 31 will be described later.

[0033] As shown in FIG. 3, the lever 31 has an end contact portion 34 and a wide surface portion 35. The end contact portion 34 has a long sliding surface 37 that contacts and slides with an end portion 36 in the transport direction F of the medium 2 transported along the transport path 8. The wide surface portion 35 is provided on the end contact portion 34. The wide surface portion 35 has a wide surface 38 with a width dimension W2 that is larger than the width dimension W1 of the end contact portion 34 in the Y-axis direction, which is the width direction intersecting the transport direction F. Here, the sliding surface 37 is located at the center of the wide surface 38 in the width direction. The sliding surface 37 protrudes from the wide surface 38 toward the upstream side in the transport direction F so that the end 36 of the medium 2 being transported comes into contact with the sliding surface 37 first. The amount of protrusion of the sliding surface 37 from the wide surface 38 is set based on the type of medium 2 expected to be transported, the degree of rigidity of each, and the limit of skew of the medium being transported. 3, the portion of the lever 31 that contacts the transported medium 2 is configured such that an end contact portion 34 having a narrow sliding surface 37 protrudes from a wide surface 38 of a wide surface portion 35. In this embodiment, the lever 31 is made by integral molding of synthetic resin.

[0034] 2 and 3, in this embodiment, the lever 31 has a free end 41 that can rotate around a shaft 39 that serves as a rotation fulcrum 40. The shaft 39 is attached to a structural member such as the frame of the image reading device 1 so as to be rotatable about the shaft. The free end 41 is made up of an end contact portion 34 and a wide surface portion 35. That is, the end contact portion 34 rotates around the shaft 39 that serves as the rotation fulcrum 40 upon contact with the medium 2 being transported. When the lever 31 rotates and the end contact portion 34 is fully rotated, the tip portion 42 of the wide surface portion 35, i.e., the tip portion 42 of the wide surface 38, is configured to come into contact with the surface 49 of the medium 2. Here, the state in which the end contact portion 34 of the lever 31 has fully rotated means that the end 36 of the medium 2 has slid against the sliding surface 37 of the end contact portion 34, passed the position of the sliding surface 37, and the lever 31 has reached the upper limit of its rotation.

[0035] The lever 31 is arranged so that when the medium 2 is not being transported, the end contact portion 34 and the wide surface portion 35 extend into the transport path 8, as shown in FIG. 2. A torsion coil spring (not shown) is provided on the shaft portion 39. The torsion coil spring applies a spring force so that the lever 31 rotates clockwise in FIG. 2. The lever 31 is provided with a recessed regulated portion 45. When the lever 31 rotates clockwise due to the spring force, the regulated portion 45 abuts against the regulating portion 46, stopping the rotation, and the lever 31 extends into the transport path 8, as shown by the solid line in FIG. 2. When the conveyed medium 2 comes into contact with the lever 31, the lever 31 rotates counterclockwise against the spring force, reaching the state shown by the dashed line in Fig. 2, i.e., the state where the end contact portion 34 has fully rotated. When one sheet of medium 2 passes and the lever 31 is no longer in contact with the medium 2, the spring force returns the lever 31 to the state where it has advanced into the conveyance path 8, shown by the solid line in Fig. 2. The regulating portion 46 is provided using the shaft of the drive roller 17.

[0036] Lever 31 has a sector-shaped light-shielding portion 44 at shaft portion 39. Light-shielding portion 44 rotates integrally with shaft portion 39 as lever 31 rotates. Sensor 32 is an optical sensor having a light-emitting portion and a light-receiving portion (not shown). When the lever 31 is in the position shown by the solid line in Fig. 2, the light-shielding portion 44 is in a position that does not block the light emitted from the light-emitting portion of the sensor 32, so the sensor 32 is OFF. When the lever 31 is in the position shown by the dashed line in Fig. 2, the light-shielding portion 44 is in a position that blocks the light emitted from the light-emitting portion of the sensor 32, so the sensor 32 is ON. When the sensor 32 is in the ON state, the medium 2 is passing through.

[0037] 2 and 3, in this embodiment, the long sliding surface 37 is inclined in the longitudinal direction relative to the wide surface 38. The inclination is achieved by increasing the amount of protrusion of the sliding surface 37 from the wide surface 38 on the side closer to the shaft portion 39 and decreasing it on the side farther from the shaft portion 39. The partially enlarged view in Figure 2 shows the state in which end 36 of medium 2 in the transport direction F slides along sliding surface 37 after contacting sliding surface 37 and just before passing over tip portion 43 of sliding surface 37. In other words, it shows the state just before end contact portion 34 has fully rotated. Note that this partially enlarged view is shown in perspective to make the structure easier to understand, and furthermore, medium 2 is shown by dashed lines, although it is positioned in front of sliding surface 37 and wide surface 38.

[0038] Because sliding surface 37 is long, when end 36 of medium 2 comes into contact with sliding surface 37 and lever 31 begins to rotate, the portion of end 36 of medium 2 that is in contact with sliding surface 37 slides while maintaining contact with sliding surface 37 and advances in conveyance direction F. As medium 2 advances in conveyance direction F, the contact position with sliding surface 37 gradually and continuously shifts from end 36 toward the surface side. In other words, surface portion 47, which is the portion in contact with sliding surface 37, changes into a state in which it is in contact with sliding surface 37. As a result, the medium 2 begins to bend concavely, starting from the position of the surface portion 47 that is in contact with the sliding surface 37. That is, of the surface portions of the medium 2 on the leading edge side in the conveying direction F of the medium 2, other surface portions 48 in the width direction (Y direction) that are continuous with the surface portion 47 that is in contact with the sliding surface 37 begin to approach the wide surface 38. If the medium 2 has low rigidity, not only will the surface portion 47 be in contact with the sliding surface 37, but the other surface portions 48 will also be in contact with the wide surface 38. 2, the position of the medium 2, i.e., the position where the medium 2 contacts the sliding surface 37, is the position where the amount of protrusion of the sliding surface 37 from the wide surface 38 is reduced by the inclined structure. At this position, the other surface portion 48 of the medium 2 is more likely to contact the wide surface 38.

[0039] In this embodiment, as described above, when the end contact portion 34 is fully rotated, the tip portion 42 of the wide surface portion 35, i.e., the tip portion 42 of the wide surface 38, is configured to contact the surface 49 of the medium 2. Furthermore, the tip portion 43 of the end contact portion 34, i.e., the tip portion 43 of the sliding surface 37, is also configured to contact the surface 49 of the medium 2. That is, in this embodiment, when the end contact portion 34 is fully rotated, both the tip portion 42 of the wide surface portion 35 and the tip portion 43 of the end contact portion 34 are configured to contact the surface 49 of the medium 2. In other words, the amount of protrusion of the tip portion 43 of the end contact portion 34 from the wide surface 38 is substantially zero.

[0040] In this embodiment, the width dimension W2 of the wide surface 38 is set to a dimension larger than 8.5 mm. This is set based on the fact that the hole size of loose-leaf paper is usually 8.5 mm. Here, the width dimension W2 of the wide surface 38 is formed to be 8.5 mm. In addition, since the positions of the holes in the loose-leaf sheets being conveyed do not often coincide with the position of the wide surface 38 in the conveying direction F, and considering variations in the positions of the holes, the width W2 of the wide surface 38 may be set to be smaller than 8.5 mm. For example, it may be set to half that, 4.25 mm. In this embodiment, the end contact portion 34 is disposed at the center in the width direction (Y-axis direction) that intersects with the transport direction F of the transport path 8 along which the medium 2 is transported.

[0041] [Modification of the first embodiment] In a modification of the first embodiment, the lever 31 is configured to be movable, i.e., rotatable, in the forward and reverse directions of the conveying direction F. This is achieved by using two torsion coil springs with spring forces in opposite directions. That is, this is achieved by positioning the lever 31 shown by the solid line in FIG. 2 at a position where the spring forces of the two torsion coil springs are balanced. In this case, the restricting portion 46 and the restricted portion 45 are not provided. Here, the forward direction is a direction away from the medium loading unit 6 on the transport path 8, and the reverse direction is a direction approaching the medium loading unit 6. Furthermore, the end contact portion 34 and the wide surface portion 35 are provided on both the surface facing in the forward direction and the surface facing in the reverse direction, respectively.

[0042] <Explanation of the Function of Embodiment 1> The end 36 of the medium 2 in the conveying direction F first contacts the sliding surface 37 of the narrow end contact portion 34 that protrudes from the wide surface 38. Because the sliding surface 37 is long, when the end 36 of the medium 2 contacts the sliding surface 37 and the lever 31 begins to rotate, the portion of the end 36 of the medium 2 that contacts the sliding surface 37 slides and advances in the conveying direction F while maintaining contact with the sliding surface 37. As the medium 2 advances in the conveying direction F, the contact position with the sliding surface 37 gradually and continuously shifts from the end 36 toward the surface. Accordingly, as shown in the partially enlarged view of FIG. 2 , the medium 2 begins to bend concavely, starting from the contact point with the sliding surface 37. That is, another surface portion 48 in the width direction of the leading edge of the medium 2 in the conveying direction F, which is continuous with the portion 47 that contacts the sliding surface 37, begins to approach the wide surface 38. The degree to which surface portion 48 of medium 2 approaches wide surface 38 varies depending on the rigidity of medium 2. Medium 2 with high rigidity is often transported with surface portion 47 in contact only with sliding surface 37 and surface portion 48 not in contact with wide surface 38. On the other hand, medium 2 with low rigidity is often transported with surface portion 47 in contact with sliding surface 37 and surface portion 48 in contact with wide surface 38 as well. That is, the medium 2 with low rigidity receives the reaction force of the lever 31 at both the surface portion 47 contacting the sliding surface 37 of the medium 2 and the surface portion 48 contacting the wide surface 38 .

[0043] <Explanation of Effects of Embodiment 1> (1-1) In this embodiment, the lever 31 includes an end contact portion 34 having a long sliding surface 37 that contacts and slides with an end portion 36 in the transport direction F of the medium 2 transported along the transport path 8, and a wide surface portion 35 that is provided on the end contact portion 34 and has a wide surface 38 with a width dimension W2 that is larger than the width dimension W1 of the end contact portion 34 in the width direction (Y-axis direction) that intersects with the transport direction F. Furthermore, the lever 31 protrudes from the wide surface 38 so that the end portion 36 of the medium 2 being transported comes into contact with the sliding surface 37 first. With this configuration, as explained above, the medium 2 having low rigidity receives the reaction force of the lever 31 on both the surface portion 47 that contacts the sliding surface 37 of the medium 2 and the surface portion 48 that contacts the wide surface 38. This prevents the reaction force from the lever 31 from concentrating on the narrow sliding surface 37, as in the past, and thereby reduces the risk that the end 36 of the medium 2 and the surface portions 47 and 48 connected to the end 36 will be deformed by the reaction force. Furthermore, the width of the sliding surface 37 that contacts the end 36 of the medium 2 can be narrowed, and the lever 31 can accurately detect the position of the medium 2 being transported. (1-2) Furthermore, when medium 2 is a sheet of paper with holes formed therein, such as loose-leaf paper, as described above, the contact position of medium 2 with sliding surface 37 gradually and continuously shifts from end 36 toward the surface as medium 2 moves in conveyance direction F. In this case, if end contact portion 34 and the hole are aligned in a straight line in conveyance direction F, when end 36 on the leading edge side of medium 2 passes the contact position with sliding surface 37, the leading edge portion of end contact portion 34, i.e., leading edge portion 43, is likely to fall into the hole. However, in this embodiment, the presence of wide surface portion 35 reduces the risk of medium 2 falling into the hole.

[0044] (2) In this embodiment, the lever 31 can rotate around the shaft 39 as a pivot point 40, with the end contact portion 34 and the wide surface portion 35 serving as free ends 41. Furthermore, the lever 31 is configured so that when the end contact portion 34 has fully rotated due to contact with the medium 2 being transported, a tip portion 42 of the wide surface portion 35 comes into contact with the surface 49 of the medium 2. That is, when the end 36 of the medium 2 passes the position of the sliding surface 37 and the lever 31 has rotated completely, the tip portion 42 of the wide surface portion 35 is configured to contact the surface 49 of the medium 2, so the subsequent transport state of the medium 2 is more stable than when the medium 2 is transported in contact with only the end contact portion 34.

[0045] (3) In this embodiment, the sliding surface 37 is inclined relative to the wide surface 38, and the amount of protrusion of the sliding surface 37 from the wide surface 38 is greater on the side closer to the shaft portion 39 and smaller on the side farther from the shaft portion 39. This makes it possible to obtain the effect of the first aspect more effectively than in a structure in which the sliding surface 37 is not inclined relative to the wide surface 38. (4) In this embodiment, the width W2 of the wide surface 38 is greater than 8.5 mm, which reduces the risk of ordinary loose-leaf paper falling into the holes.

[0046] (5) In a modification of this embodiment, the lever 31 is movable in both the forward and reverse directions of the conveying direction F, and the end contact portion 34 and the wide surface portion 35 are provided on both the surface facing the forward direction and the surface facing the reverse direction, respectively. This allows the effect described in (1) above to be obtained for conveying the medium 2 in both the forward and reverse directions relative to the end contact portion 34. (6) In this embodiment, the end contact portion 34 is configured to be located at the center in the width direction (Y-axis direction) that intersects with the conveying direction F of the conveying path 8 along which the medium 2 is conveyed. In other words, since the end contact portion 34 is located at approximately the center of the width of the medium 2, the accuracy of detecting the presence or absence of the medium 2 can be improved.

[0047] [Embodiment 2] Next, a medium detection device 23 according to a second embodiment will be described with reference to Fig. 4. The same parts as those in the first embodiment will be given the same reference numerals, and a description of the configurations and corresponding effects will be omitted. The medium detection device 23 of the second embodiment differs from that of the first embodiment in the shape of the wide surface portion 35. Specifically, the wide surface portion 35 is configured so that the width gradually decreases from the tip portion 42 toward the base portion 42. In other words, the wide surface 38 of the wide surface portion 35 is configured so that the shape in a plan view is approximately triangular.

[0048] In this embodiment, the width of the wide surface portion 35 is configured to gradually decrease from the tip portion 42 toward the base portion, thereby making it possible to suppress the increase in weight due to the provision of the wide surface portion 35 compared to a substantially rectangular shape.

[0049] [Embodiment 3] Next, a medium detection device 23 according to a third embodiment will be described with reference to Fig. 5. The same parts as those in the first embodiment will be given the same reference numerals, and a description of the configurations and corresponding effects will be omitted. In the medium detection device 23 of the third embodiment, the wide surface portion 35 is configured to exist in a range extending from the position where the conveyed medium 2 first comes into contact in the region where the end contact portion 34 extends to the tip portion 42. In other words, the portion on the sliding surface 37 of the end contact portion 34 that corresponds to the portion opposite the tip portion 42 of the wide surface portion 35 is the position where the medium 2 first comes into contact. Here, in this specification, the "first contact position" in the area where the end contact portion 34 extends and where the transported medium 2 first comes into contact does not necessarily have to be a position that is strictly determined to be a single point, but is used to mean a position having a range that takes into account the displacement of the leading edge position of the transported medium 2, etc.

[0050] In this embodiment, the wide surface portion 35 is configured to exist in a range extending from the position where the conveyed medium 2 first comes into contact in the region where the end contact portion 34 extends to the tip portion 42. This makes it possible to suppress an increase in weight due to the provision of the wide surface portion 35.

[0051] <How to determine the amount of protrusion from the wide surface of the sliding surface> Next, a method for determining the amount of protrusion h of the sliding surface 37 of the end contact portion 34 from the wide surface 38 will be described with reference to FIGS. Figure 6 shows a case where paper, which is medium 2, approaches sliding surface 37 of end contact portion 34 perpendicularly. In Figure 6, angle θ1 is the allowable paper rotation angle. The allowable paper rotation angle θ1 is the maximum allowable angle of inclination when paper is transported at an angle along transport path 8. The protrusion amount h is determined so that even if the paper is transported at an angle θ1, the leading edge of the paper will first contact sliding surface 37 rather than wide surface 38. The amount of protrusion h is calculated by h=[(W2-W1) / 2]×tan θ1.

[0052] Figure 7 shows a case where the medium 2 approaches the sliding surface 37 of the end contact portion 34 at a plunge angle θ2 rather than perpendicularly. When approaching the sliding surface 37 at a plunge angle θ2 rather than perpendicularly, the protrusion amount h calculated in Figure 6 becomes the distance in the direction shown in Figure 7. This makes it possible to ensure the necessary protrusion amount h even if the thickness of the end contact portion 34 is thin. In other words, by approaching the sliding surface 37 at a plunge angle θ2, the thickness of the end contact portion 34 can be thinned.

[0053] Other Embodiments The media detection device 23 of the present invention and the image reading device 1 equipped with this media detection device 23 are based on the configuration of the embodiment described above, but it is of course possible to modify or omit partial configurations within the scope of the gist of the present invention. In the above embodiment, the image reading device 1 is described as the electronic device, but it is needless to say that the electronic device is not limited to this image reading device, and can also be applied to an image forming device such as a printer. In the above embodiment, the movement of the lever 31 is described as a rotational movement, but it is not limited to a rotational movement. The movement may be such that the end contact portion 34 moves backward in a direction intersecting with the sliding surface 37. Furthermore, the wide surface portion 35 may be formed by adhering a lightweight sheet material to the end contact portion 34, rather than by integral molding of synthetic resin with the end contact portion 34. This makes it possible to prevent an increase in the weight of the lever 31. [Explanation of symbols]

[0054] 1...image reading device, 2...medium, 3...first reading unit, 4...medium feeding unit, 5...medium transport unit, 6...medium placement section, 7...feed roller, 8...conveyance path, 9...feed roller pair, 10...first conveying roller pair, 11...second conveying roller pair, 12...Third conveying roller pair, 13...Feed roller, 14...Separation roller, 15...driving roller, 16...followed roller, 17...driving roller, 18... driven roller, 19... driving roller, 20... driven roller, 21... curved path, 22... driven roller, 23... medium detection device, 24... second reading unit, 25... glass table, 31... lever, 32... sensor, 34... end contact portion, 35... wide surface portion, 36...end of medium, 37...sliding surface, 38...wide surface, 39...shaft portion, 40...rotation fulcrum, 41...free end, 42...tip portion of wide surface portion, 43...tip portion of end contact portion, 44...light-shielding portion, 45...regulated portion, 46...regulating portion, 47...surface portion connected to the edge of the medium, 48...other surface portion connected to the end of the medium, 49...surface of the medium, θ1...allowable paper rotation angle, θ2...entry angle, F...transport direction, W1: Width of contact end, W2: Width of wide surface

Claims

1. a lever disposed on the transport path and movable by contact with the medium transported in the transport direction along the transport path; a sensor that detects the medium based on the movement of the lever; The lever is an end contact portion having a long sliding surface that contacts and slides with an end portion in the transport direction of the medium transported along the transport path; a wide surface portion provided on the end contact portion, the wide surface having a width dimension larger than the width dimension of the end contact portion in a width direction intersecting the conveying direction, the sliding surface protrudes from the wide surface so that an end of the medium being transported comes into contact with the sliding surface first; A medium detection device.

2. 2. The medium sensing device according to claim 1, the lever is rotatable with the shaft portion as a pivot point, and the end contact portion and the wide surface portion serve as free ends; When the end contact portion has fully rotated due to contact with the medium during transport, the tip of the wide surface portion comes into contact with the surface of the medium. A medium detection device.

3. 3. The medium sensing device according to claim 2, the sliding surface is inclined relative to the wide surface, a protrusion amount of the sliding surface from the wide surface is large on a side closer to the shaft portion and small on a side farther from the shaft portion; A medium detection device.

4. 2. The medium sensing device according to claim 1, The width dimension of the wide surface is greater than 8.5 mm. A medium detection device.

5. 2. The medium sensing device according to claim 1, the lever is movable in the forward and reverse directions of the conveying direction, the end contact portion and the wide surface portion are provided on both the surface facing in the forward direction and the surface facing in the reverse direction, respectively; A medium detection device.

6. 2. The medium sensing device according to claim 1, the end contact portion is disposed at a center portion in a width direction intersecting the transport direction of the transport path along which the medium is transported, the width direction intersecting the transport direction. A medium detection device.

7. 3. The medium sensing device according to claim 2, The width dimension of the wide surface portion gradually decreases from the tip portion toward the base portion. A medium detection device.

8. 3. The medium sensing device according to claim 2, the wide surface portion is present in a range extending from a position where the medium being conveyed first comes into contact with the end contact portion to the tip portion in the region where the end contact portion extends; A medium detection device.

9. A medium detection device according to any one of claims 1 to 8; a medium transport unit that transports the medium along the transport path; a processing unit that executes processing on the transported medium.

Images