JP5748534B2 - Sheet information reader - Google Patents

Description

  The present invention relates to a sheet information reading apparatus such as a scanner, and more particularly to an information reading unit that reads information on a sheet and a structure that urges a facing member such as a driven roller that faces a driving roller that conveys the sheet.

  A sheet information reading device such as a scanner includes an information reading unit that reads information on a conveyed sheet. The information reading unit is a part provided with information reading means (sensor) for reading image information or magnetic information on a sheet such as an image sensor.

  FIG. 14 shows a structure having a contact image sensor 100 as information reading means. The image sensor 100 is disposed in the middle of the sheet conveyance path 101 of the scanner. The image sensor 100 reads information on a sheet conveyed along the sheet conveyance path 101 via a contact glass 100 a installed on the image sensor 100. Such an image sensor 100 is supported by a conveyance frame 101 a constituting the sheet conveyance path 101.

  A platen roller 102 is disposed at a position facing the image sensor 100. The image sensor 100 is urged toward the platen roller 102 by a pressure spring 103. A sheet is sandwiched between the image sensor 100 and the platen roller 102, and the sheet is brought into close contact with the contact glass 100 a of the image sensor 100.

  Drive rollers 104a and 105a and driven rollers 104b and 105b for conveying sheets are provided upstream and downstream of the image sensor 100 in the sheet conveyance direction, respectively. The driven rollers 104b and 105b are urged by the pressure springs 104c and 105c toward the driving rollers 104a and 105a facing each other. Thereby, each drive roller and driven roller form a nip portion, and the sheet is conveyed while being nipped.

  Further, a shield member 106 formed of a conductive plate member is disposed so as to surround the periphery of the image sensor 100 excluding the reading unit side that reads information on the sheet. The shield member 106 is grounded, and discharges static electricity generated during sheet conveyance to the ground. Thereby, it is possible to prevent noise generated by static electricity from adversely affecting the read image or the like.

  On the other hand, in the structure having the contact image sensor as described above, a configuration in which a shield member and a pressure spring that biases the image sensor toward the platen roller are integrally formed is known (see Patent Document 1). ). In the case of this configuration, it is possible to reduce the cost by reducing the number of parts.

Japanese Patent No. 3805243

  In both cases of the structure shown in FIG. 14 and the structure described in Patent Document 1, a pressure spring that biases the image sensor toward the platen roller, and a biasing roller that biases the driven roller toward the drive roller. A pressure spring is provided separately. For this reason, the number of parts increases and it takes time to assemble, but further reduction in the number of parts is desired in order to reduce the cost of the scanner.

  In view of such circumstances, the present invention has a structure that urges the information reading unit and a facing member such as a driven roller, and has a structure that can reduce the number of parts and improve the assemblability and reduce the cost. It is to provide.

The sheet information reading apparatus according to the present invention includes a driving roller that conveys a sheet along a conveying path, a facing member that is disposed to face the driving roller and sandwiches the sheet with the driving roller, and the facing member. An information reading unit that is adjacent to the sheet conveyance direction and reads the information on the sheet; and an integral urging unit that urges the counter member toward the driving roller and urges the information reading unit toward the conveyance path. A first urging unit that urges the opposing member toward the driving roller, and a second urging unit that urges the information reading unit toward the conveyance path. An urging portion, and a shield member that is formed of an electrically conductive material having elasticity and is disposed so as to surround at least the side of the information reading unit that faces the conveyance path, and is grounded. The first energizing And the second biasing portion, the shield member and are integrally formed, characterized in that.
The sheet information reading apparatus of the present invention includes a driving roller that conveys a sheet along a conveying path, a facing member that is disposed to face the driving roller and sandwiches the sheet with the driving roller, and the facing An information reading unit that is adjacent to the member in the sheet conveyance direction and reads the information on the sheet; and the counter member is biased toward the driving roller and the information reading unit is biased toward the conveyance path. An urging unit, and the integrated urging unit urges the counter member toward the driving roller and urges the information reading unit toward the conveyance path. A second urging portion, and the opposing member is a driven roller that is driven to rotate in contact with the drive roller, and the driven roller has a driven rotation shaft formed of a conductive member, Grounded via the first biasing part. That, characterized in that.
The sheet information reading apparatus of the present invention includes a driving roller that conveys a sheet along a conveying path, a facing member that is disposed to face the driving roller and sandwiches the sheet with the driving roller, and the facing An information reading unit that is adjacent to the member in the sheet conveyance direction and reads the information on the sheet; and the counter member is biased toward the driving roller and the information reading unit is biased toward the conveyance path. An urging unit, and the integrated urging unit urges the counter member toward the driving roller and urges the information reading unit toward the conveyance path. A second urging portion, and the opposing member is a driven roller that rotates in contact with the drive roller, and the driven roller has a driven rotation shaft supported by a rotation support portion of the apparatus main body. Through the driven rotating shaft Wherein while being supported by the rotation support portion, the driven rotating shaft is urged to the drive roller side by being biased by the first biasing part, it is characterized.
The sheet information reading apparatus of the present invention includes a driving roller that conveys a sheet along a conveying path, a facing member that is disposed to face the driving roller and sandwiches the sheet with the driving roller, and the facing An information reading unit that is adjacent to the member in the sheet conveyance direction and reads the information on the sheet; and the counter member is biased toward the driving roller and the information reading unit is biased toward the conveyance path. And a biasing means that biases the opposing member toward the drive roller, and biases the information reading means toward the conveyance path. A second urging portion, and the opposing member is a driven roller that is driven to rotate in contact with the drive roller, and includes a holder that supports the driven roller and a conveyance path that conveys the sheet. Integrated with the frame Is, has a holder support for supporting said holder, said driven roller, the is biased through the holder by first biasing part, and wherein the.

  According to the present invention, the integral urging means urges the opposing member toward the driving roller and urges the information reading means toward the conveyance path. Therefore, it is necessary to separately provide these urging members. The number of parts can be reduced. As a result, the assemblability can be improved and the cost can be reduced.

1 is a schematic cross-sectional view of a sheet information reading apparatus according to a first embodiment of the present invention. FIG. The cross-sectional view of an image sensor. The perspective view of an image sensor. The perspective view which shows the assembly | attachment state to the conveyance frame of an image sensor. The perspective view which takes out and shows the sensor accommodating part and driven roller of a conveyance frame. (A) of the shielding member which concerns on 1st Embodiment is a perspective view, (B) is a roll sectional view of (A). The perspective view which shows the state which assembled | attached the shield member based on 1st Embodiment to the conveyance frame and a driven roller. (A) of the shielding member which concerns on the 2nd Embodiment of this invention is a perspective view, (B) is a ha sectional drawing of (A). The perspective view which shows the state which assembled | attached the shield member based on 2nd Embodiment to the conveyance frame and the driven roller. The figure similar to FIG. 2 which concerns on the 3rd Embodiment of this invention. The perspective view of the conveyance frame which concerns on 3rd Embodiment. The holder which concerns on 3rd Embodiment, (A) is the perspective view seen from the conveyance path side, (B) is the perspective view seen from the opposite side to (A). The figure similar to FIG. 2 which shows an example of a conventional structure.

<First Embodiment>
A first embodiment of the present invention will be described with reference to FIGS.

[Sheet information reading device]
As shown in FIG. 1, a sheet information reading device (hereinafter referred to as a scanner) 1 includes a sheet feeding unit 2 that feeds a sheet S, an information reading unit 3 that reads information on the sheet S, and a discharge that discharges the sheet S. Part 4. Then, image information on the sheet S fed from the sheet feeding unit 2 is read by the information reading unit 3, and the sheet S on which the information is read is discharged from the discharge unit 4.

[Paper Feeder]
The sheet feeding unit 2 is disposed on the upper part of the apparatus main body 11 of the scanner 1, is disposed opposite to the feed roller 22 that is a conveying member, the tray 21 on which the sheet S is placed, and a separation member. And a certain separation roller 23. The tray 21 is disposed so as to be inclined above the paper feed port 12 provided in the upper part of the apparatus main body 11. The feed roller 22 is a feed roller (conveyance roller) for feeding the sheet S toward the information reading unit 3, is provided on the cover unit 11 b of the apparatus main body 11, and is rotationally driven by a motor that is a drive source (not shown). The Then, the sheet S comes into contact with the sheet S on the tray 21 and is conveyed into the conveyance path 13 toward the information reading unit 3. In the case of this embodiment, the feed roller 22 is disposed at a position facing the central portion in the width direction of the tray 21.

  Further, a separation roller 23 is provided at a position facing the feed roller 22 downstream of the tray 21 in the sheet conveyance direction by the feed roller 22. The separation roller 23 is supported by the feed roller 22 so as to be movable in a far and near direction, and is urged in a direction toward the feed roller 22 by a spring (not shown). The separation roller 23 applies a force in the direction opposite to the rotation direction of the feed roller 22 to the sheet by a motor which is a driving unit (not shown). When the sheet is conveyed by the feed roller 22, a force in the direction opposite to the rotation direction of the feed roller 22 is applied to the sheet, thereby generating a sheet resistance acting in the direction opposite to the sheet conveyance direction. It is easy to separate from the sheet. The separation roller 23 is provided with a torque limiter so that power transmission from the motor can be cut off when a torque exceeding a predetermined value is applied.

  Further, the positional relationship between the feed roller 22 and the separation roller 23 in the sheet conveyance direction is a position where the feed roller 22 is shifted upstream of the separation roller 23 in the sheet conveyance direction by the feed roller 22. This makes it easy to pick up the sheet S on the tray 21.

  In the case of the present embodiment, the apparatus main body 11 is separable into a main body part 11a and a cover part 11b with a conveyance path 13 through which the sheet S is conveyed in the apparatus main body 11 as a boundary. The main body 11a is provided with the tray 21 and the separation roller 23 described above, and the feed roller 22 is supported by the cover 11b. The cover part 11b is rotatable with respect to the main body part 11a around the lower end portion of the main body part 11a. When the cover portion 11b is rotated, the conveyance path 13 is exposed (opened), and a sheet jammed in the conveyance path 13 can be removed.

  When the cover portion 11b is closed, the feed roller 22 contacts the separation roller 23, and the separation roller 23 sinks in a direction opposite to the spring biasing direction (moves away from the feed roller 22). As a result, the feed roller 22 and the separation roller 23 are in elastic contact with each other.

[Information reading unit]
As shown in FIGS. 1 and 2, the information reading unit 3 is disposed at an intermediate portion in the sheet conveyance direction of the apparatus main body 11, and includes a pair of conveyance rollers 31 and 32, an image sensor 33 as information reading means, and a regulating member. A platen roller 34 and a shield member 36 are provided. The conveyance roller pairs 31 and 32 are disposed upstream and downstream of the image sensor 33 in the sheet conveyance direction, respectively, and convey the sheet while sandwiching the sheet. For this purpose, the conveyance roller pair 31 and 32 is composed of driving rollers 31a and 32a and driven rollers 31b and 32b as opposing members, respectively.

  Of these, the driving rollers 31a and 32a are respectively supported by the main body 11a and are driven to rotate by a motor which is a driving source (not shown). The driven rollers 31b and 32b are arranged to face the driving rollers 31a and 32a, respectively, and sandwich the sheet between the driving rollers 31a and 32a. Such driven rollers 31b and 32b are supported by the cover portion 11b so as to be rotatable and movable relative to the driving rollers 31a and 32a, respectively. Further, driven rollers 31b and 32b are urged to drive rollers 31a and 32a by a projecting plate portion 38 which is a first urging portion described later, and nips are respectively formed between the driven rollers 31b and 32b and the drive rollers 31a and 32a. Portions N1 and N2 are formed. When the driving rollers 31a and 32a are rotated, the driven rollers 32a and 32b are driven and rotated, and the sheet sandwiched between the nip portions N1 and N2 is conveyed in the same direction as the conveying direction by the feed roller 22.

  The image sensor 33 is a CIS (contact image sensor), and is arranged adjacent to (following) the driven rollers 31b and 32b in the sheet conveyance direction, and reads information on the surface of the sheet. As shown in FIG. 3, the image sensor 33 includes an LED 33b that is a light source (light emitting element), a lens array 33c, and a light receiving element 33d in a frame 33a that is a casing. Further, a contact glass 33e is installed on the surface of the frame 33a on the transport path 13 side. Further, as shown in FIG. 4, the image sensor 33 is long in the sheet width direction (a direction orthogonal to the conveyance direction) and corresponds to the maximum sheet width that can be conveyed. And it is comprised so that the information of the whole sheet width direction can be read.

  The image sensor 33 configured in this manner emits light by the LED 33b when the sheet conveyed in the conveyance path 13 passes through a position facing the contact glass 33e. The emitted light is irradiated onto the sheet at the image reading position A, and the reflected light is imaged on the light receiving element 33d via the lens array 33c. Then, after photoelectric conversion, the image information is read as an electrical signal.

  Since the image sensor 33 having such a configuration has a shallow depth of focus, it is necessary to bring the sheet into close contact with the surface of the contact glass 33e when reading information on the sheet satisfactorily. Therefore, in this embodiment, a platen roller 34 is provided on the side opposite to the reading position of the image sensor 33 so that the sheet is pressed against the contact glass 33e of the image sensor 33.

  That is, the platen roller 34 is disposed so as to be rotatable to a position facing the contact glass 33e of the image sensor 33 of the main body portion 11a, and the perspective movement with respect to the image sensor 33 is impossible. Further, in order to prevent the generation of a load due to contact between the contact glass 33e and the platen roller 34, the platen roller 34 is disposed with a predetermined minute gap with respect to the contact glass 33e. The platen roller 34 configured in this manner regulates the sheet position with respect to the image sensor 33.

  On the other hand, the image sensor 33 is supported by the cover portion 11b so as to be movable toward and away from the platen roller 34, and is urged toward the platen roller 34 by a bent plate portion 39 which is a second urging portion described later. The position of the sheet conveyed between the image sensor 33 and the platen roller 34 is restricted by the platen roller 34. In this state, the image sensor 33 is urged toward the platen roller 34, whereby the sheet is relatively pressed against the contact glass 33e.

  This will be described more specifically. As shown in FIG. 5, the image sensor 33 forms a conveyance path 13, and a sensor storage portion 35 a formed integrally with a resin conveyance frame 35 fixed to the cover portion 11 b has an arrow a from the side opposite to the reading portion. Stored in the direction. Here, hook portions 35b are integrally formed on both side portions of the sensor storage portion 35a of the transport frame 35, respectively. The hook portion 35b is a plate-like one whose base end is continuous with the transport frame 35, and a protrusion having an inclined surface 35b-1 and a stopper surface 35b-2 is integrally formed on the inner side of the tip end.

  When the image sensor 33 is stored in the sensor storage portion 35a from the direction of the arrow a, both ends of the image sensor 33 press the inclined surface 35b-1 of the hook portion 35b and push the hook portion 35b apart. When the image sensor 33 is stored in the sensor storage portion 35a, the hook portion 35b returns to its original state, the stopper surfaces 35b-2 are locked to both ends of the surface of the image sensor 33, and the image sensor 33 is stored in the sensor storage portion 35a. It is prevented from falling off from the portion 35a. Since the depth of the sensor storage portion 35a is deeper than the thickness of the image sensor 33, the image sensor 33 can move within the sensor storage portion 35a.

  As shown in FIG. 6, the transport frame 35 has a bottom plate 35 c on the side opposite to the opening side of the sensor storage portion 35 a that stores the image sensor 33. A plurality (two in the illustrated example) of openings 35d and a plurality (three in the illustrated example) of hooks 35e are formed in the bottom plate 35c. The hook portion 35e is formed by projecting from the bottom plate 35c and bending in the same direction with respect to the width direction from both ends and the center portion of the bottom plate 35c in the width direction (direction orthogonal to the sheet conveying direction). The opening 35d is formed between the three hook portions 35e so as to penetrate the bottom plate 35c.

  As shown in FIG. 6, driven rollers 31b and 32b are disposed on both sides of the sensor storage portion 35a of the conveyance frame 35 in the sheet conveyance direction. The driven rollers 31 b and 32 b have driven rotary shafts 31 c and 32 c that are grounded via the rotation support portion of the cover portion 11 b of the apparatus main body 11. Each of the driven rotating shafts 31c and 32c of the driven rollers 31b and 32b is formed of a conductive member (conductive material).

  In the case of this embodiment, a shield member 36 is disposed on the side opposite to the reading side of the image sensor 33. The shield member 36 is a member that holds the image sensor 33. In the present embodiment, for example, such a shield member 36 is formed of an elastic conductive material, and is disposed so as to surround at least the side of the image sensor 33 that faces the platen roller 34 (reading unit). And grounded. Such a shield member 36 is formed integrally with the first urging portion (projecting plate portion 38) and the second urging portion (folded plate portion 39) described above. In other words, the shield member 36 constitutes an integral urging unit that urges the driven rollers 31 b and 32 b toward the driving rollers 31 a and 32 a and urges the image sensor 33 toward the platen roller 34. Further, the shield member 36 is disposed and fixed so as to surround the sensor storage portion 35a of the transport frame 35 in which the image sensor 33 is disposed.

  That is, as shown in FIGS. 2 and 7, the shield member 36 is made of sheet metal obtained by performing predetermined processing on a metal plate such as phosphor bronze or stainless steel, and includes a case portion 37, a protruding plate portion 38, and a bent portion. And a plate portion 39. The case portion 37 is formed in a substantially rectangular parallelepiped shape with a part opened, and surrounds the image sensor 33. The substrate portion 37a and the substrate portion 37a (the sheet conveying direction in the assembled state) are both bent in the same direction. And a pair of side plate portions 37b. Projecting plate portions 38 are respectively formed at intermediate portions in the longitudinal direction (width direction in the assembled state) of the side plate portions 37b. The protruding plate portion 38 is formed so as to protrude toward the driven rollers 31b and 32b (opposing member side) in the assembled state of the shield member 36 with respect to the apparatus main body 11. A plurality (three in the illustrated example) of openings 37c and a plurality (two in the illustrated example) of bent plate portions 39 are formed in the substrate portion 37a.

  The shield member 36 configured as described above is formed by punching a metal plate and performing a bending process. In other words, the substrate portion 37a and the pair of side plate portions 37b are formed by bending both ends of the substantially rectangular metal plate. Further, two cuts are made in the middle part of the pair of side plate parts 37b from the middle part to the edge in the direction perpendicular to the longitudinal direction, and the part between the cuts is bent so that the edge faces outward. Thus, the protruding plate portion 38 protruding from the side plate portion 37b is formed.

  In the case of the illustrated example, the portion of the side plate portion 37b before the protruding plate portion 38 is bent is protruded from the other portion of the side plate portion 37b. That is, the width of the side plate portion 37b is increased only in the portion where the protruding plate portion 38 is formed. Thereby, the protrusion amount of the protrusion board part 38 is enlarged. The shape of the portion before forming the protruding plate portion is determined from the shape of the shield member, the position of the driven roller, and the like. Therefore, the width of the portion before the protruding plate portion 38 is formed may be the same as the other portion of the side plate portion 37b or may be shortened.

  In addition, a cut is made in two sides of the board portion 37a except for one side of the rectangle, and a portion surrounded by the three sides is directed toward the image sensor 33 arranged in the case portion 37 (on the information reading means side). B) The bent plate portion 39 is formed by bending. The position where the bent plate portion 39 is formed is a position corresponding to the opening 35d in a state where the shield member 36 is disposed on the transport frame 35 as will be described later. The front end portion of the bent plate portion 39 is bent to the side opposite to the bending direction.

  Further, three openings 37c are formed by punching out three portions of the substrate portion 37a. The positions where the openings 37c are formed are positions corresponding to the hook portions 35e in a state where the shield member 36 is disposed on the transport frame 35 as described below.

  As described above, the protruding plate portion 38 constitutes a first urging portion that urges the driven rollers 31 b and 32 b, and the bent plate portion 39 constitutes a second urging portion that urges the image sensor 33. And the shield member 36 which has such a protrusion board part 38 and the bending board part 39 is fixed to the conveyance frame 35 in which the image sensor 33 is arrange | positioned, as shown in FIG. That is, the case portion 37 of the shield member 36 is disposed so as to cover the sensor storage portion 35 a of the transport frame 35. At this time, the hook portion 35e of the sensor storage portion 35a and the opening portion 37c of the case portion 37 are aligned, and the hook portion 35e is inserted into the opening portion 37c. Then, by hooking the hook portion 35e to the end portion of the opening portion 37c, the shield member 36 is fixed so as not to move in the thickness (depth) direction of the transport frame 35 (the direction of arrow a in FIG. 5 and the opposite direction thereof). The

  In this state, the bent plate portion 39 and the opening portion 35d of the sensor storage portion 35a are aligned, and the bent plate portion 39 enters the sensor storage portion 35a through the opening portion 35d. As shown in FIG. 2, the bent plate portion 39 elastically contacts the surface opposite to the contact glass 33e of the image sensor 33 disposed in the sensor storage portion 35a, and the image sensor 33 is moved to the platen roller. It urges toward 34 (conveyance path side). In addition, the protruding plate portion 38 elastically contacts the driven rotation shafts 31c and 32c of the driven rollers 31b and 32b disposed adjacent to the sensor storage portion 35a, so that the driven rollers 31b and 32b are respectively driven by the driving roller 31a and the driven roller 31a. It urges toward 32a (to the drive roller side).

  Thus, spring pressure is applied to the image sensor 33 and the driven rollers 31b and 32b by the protruding plate portion 38 and the bent plate portion 39 integrally formed with the shield member 36, respectively. At this time, since the shield member 36 is fixed to the transport frame 35 by the engagement of the hook portion 35e and the opening 37c, the shield member 36 can be prevented from floating from the transport frame 35 due to the repulsive force against the spring pressure. . As a result, the spring pressure by the protruding plate portion 38 and the bent plate portion 39 can be reliably applied to the image sensor 33 and the driven rollers 31b and 32b, respectively.

  In addition, in a state where spring pressure is applied to the protruding plate portion 38 or the bent plate portion 39, it is difficult to disengage the hook portion 35 e and the opening portion 37 c, so that the shield member 36 is inadvertently detached from the transport frame 35. It becomes difficult to come off. On the other hand, when the spring pressure is not applied to the protruding plate 38 or the bent plate 39, the shield member 36 can be easily attached to and detached from the transport frame 35.

  Further, since the protruding plate portion 38 and the bent plate portion 39 change the amount of bending depending on the thickness of the conveyed sheet, it is possible to stably convey the sheet having various thicknesses. In the present embodiment, the positions at which the two bent plate portions 39 urge the image sensor 33 are substantially equidistant from the center in the width direction of the image sensor 33. Further, the positions at which the two protruding plate portions 38 urge the driven rollers 31b and 32b, respectively, are the substantially axial center portions of the driven rotating shafts 31c and 32c, respectively. Accordingly, the image sensor 33 and the driven rollers 31b and 32b can be urged stably.

  Since the shield member 36 is grounded as described above, the driven rotary shafts 31c and 32c with which the protruding plate portion 38 provided integrally with the shield member 36 abuts are also grounded via the shield member 36. Will be. Thereby, static electricity generated during the conveyance of the sheet can be released from the shield member 36 to the ground. Therefore, it is possible to prevent noise generated by static electricity from adversely affecting the read image or the like.

  That is, the shield member 36 is made of metal such as phosphor bronze or stainless steel, and has conductivity. A part of the shield member 36 is indirectly connected to an electrical ground member of the apparatus main body 11 (not shown). Therefore, static electricity generated between the shaft portion and the roller portion in each of the driven rollers 31b and 32b by sheet conveyance can be released to the ground member via the shield member 36, and the influence of static electricity can be prevented in advance. Can do.

  In this embodiment, the structure example in which the driven rotating shafts 31c and 32c of the driven rollers 31b and 32b are grounded at the same time while being urged by the shield member 36 has been described. However, the present invention is not limited to this. For example, the driven rotary shafts 31c and 32c of the driven rollers 31b and 32b are grounded by another route (for example, grounded by the rotation support portion of the cover portion 11b of the apparatus main body 11), and the driven rotary shafts 31c and 32c are attached. The member to be energized may be grounded.

[Discharge part]
As shown in FIG. 1, the discharge unit 4 is disposed downstream of the apparatus main body 11 in the sheet conveyance direction, and has a U-shaped conveyance path 41 continuous with the conveyance path 13, a discharge roller pair 43, a discharge tray 44, A sheet holding member 45. Of these, the U-shaped conveyance path 41 is a conveyance path through which a U-shaped sheet is conveyed. Such a U-shaped conveyance path 41 includes a U-shaped curved surface portion 41 a formed on the lower surface of the cover portion 11 b and a U-shaped curved member 41 b connected to the apparatus main body 11 by a hinge 46. .

  The pair of paper discharge rollers 43 is provided at the exit of the U-shaped conveyance path 41 and discharges the sheet from the U-shaped conveyance path 41. The paper discharge roller pair 43 is also composed of a driving roller and a driven roller, and one roller is provided on the cover portion 11b and the other roller is provided on the bending member 41b.

  The paper discharge tray 44 is formed on the surface of the cover portion 11b opposite to the main body portion 11a, and stacks the sheets discharged from the paper discharge roller pair 43. The sheet discharge tray 44 includes an inclined surface 44a inclined in the horizontal direction, and a support surface 44b restricted so as to be bent obliquely upward from the lower end edge of the inclined surface 44a. The leading end of the support surface 44 b exists in the vicinity of the exit of the discharge roller pair 43. The sheet discharged from the discharge roller pair 43 jumps out toward the inclined surface 44a and is placed so as to overlap the inclined surface 44a while the lower end edge is supported by the supporting surface 44b.

  The sheet holding member 45 holds the sheets stacked on the paper discharge tray 44 so that the sheets do not fall from the paper discharge tray 44 due to the influence of disturbance or the like. Such a sheet restraining member 45 is provided so as to extend almost tangentially from the tip of the bending member 41b, and faces the inclined surface 44a of the sheet discharge tray 44 with the bending member 41b closed as shown in FIG. To do. As a result, the sheet discharged to the sheet discharge tray 44 is sandwiched between the inclined surface 44a and the sheet holding member 45, and is prevented from inadvertently dropping.

[Scanner operation]
In the case of this embodiment, first, a sheet (or sheet bundle) for reading information is placed on the tray 21. In this state, for example, when an operation is started by a user pressing a reading start button provided on the apparatus, the feed roller 22 is driven to rotate and the separation roller 23 is rotated in the reverse direction. Thus, in the case of a sheet bundle, the sheets are separated one by one and conveyed to the conveyance path 13. On the other hand, when the number of sheets is one, the torque limiter provided on the separation roller 23 is activated, and the power transmission to the separation roller 23 is cut. The separation roller 23 is rotated by the rotation of the feed roller 22. To do. As a result, one sheet is conveyed to the conveyance path 13.

  The sheet conveyed to the conveyance path 13 is nipped and conveyed by the conveyance roller pair 31 on the upstream side of the image sensor 33 and passes between the image sensor 33 and the platen roller 34. At this time, the sheet comes into close contact with the contact glass 33 e of the image sensor 33, and information on the sheet is read by the image sensor 33. Information read by the image sensor 33 is stored in storage means (memory) provided in the apparatus, or is sent to an external terminal (not shown) such as a personal computer.

  The sheet that has passed through the image sensor 33 is nipped by a pair of conveyance rollers 32 on the downstream side of the image sensor 33 and conveyed to the U-shaped conveyance path 41. The sheet conveyed to the U-shaped conveyance path 41 is further nipped by the discharge roller pair 43 and discharged to the discharge tray 44.

  In the case of this embodiment configured and operated in this way, the protruding plate portion 38 that is the first urging portion that urges the driven rollers 31 b and 32 b and the folding portion that is the second urging portion that urges the image sensor 33. The curved plate portion 39 is integrally formed. For this reason, it is not necessary to provide a 1st biasing part and a 2nd biasing part separately, and can reduce a number of parts. As a result, the assemblability can be improved and the cost can be reduced.

  That is, since the image sensor 33 and the driven rollers 31b and 32b are urged by using the elasticity of the shield member 36, a spring for urging the driven roller that has been separately provided becomes unnecessary, and the number of parts can be reduced. Cost can be reduced. Moreover, assemblability can be improved by reducing the number of parts.

  Further, the leaf springs such as the protruding plate portion 38 and the bent plate portion 39 do not require a space in the bending direction at the time of installation as compared with the coil spring, so that the apparatus can be miniaturized. Further, since the leaf spring has a wider portion to be pressed than the coil spring, the portion of the leaf spring that presses the driven rollers 31b and 32b can be widened in the axial direction of the driven rollers 31b and 32b. And the spring pressure concerning the driven rotating shafts 31c and 32c of the driven rollers 31b and 32b can be dispersed, and the bending of the driven rollers can be prevented.

  Further, in the present embodiment, the image sensor 33 and the shield member 36 are detachably attached to the transport frame 35 separately. At this time, as described above, the image sensor 33 and the shield member 36 can be easily attached to and detached from the transport frame 35 by the elastic force of the protruding plate portion 38 or the bent plate portion 39 of the shield member 36. In addition, since the shield member 36 and the image sensor 33 are separately attached to the transport frame 35, the operations at the time of assembly and replacement of parts are further facilitated.

  Further, by changing the width of the protruding plate 38 between the upstream side and the downstream side, an appropriate biasing force (driven pressure) is applied to each driven roller, the sheet conveyance is stabilized, and the image quality is maintained. It is also possible to reduce the number of points, improve assemblability, and downsize the device. The same effect can be obtained by deleting one of the driven spring portions provided on both the upstream side and the downstream side of the protruding plate portion 38 and arranging a coil spring instead.

<Second Embodiment>
A second embodiment of the present invention will be described with reference to FIGS. In the present embodiment, as shown in FIG. 9, a plurality of protruding plate portions 38 formed on the shield member 36 are provided for each side plate portion 37b. In the illustrated example, two pieces are formed. As shown in FIG. 10, with the shield member 36 attached to the conveyance frame 35, both end portions of the driven rotating shafts 31c and 32c of the driven rollers 31b and 32b are urged.

  In the case of this embodiment configured as described above, by providing a plurality of projecting plate portions 38 for urging the driven rollers 31b and 32b, the spring pressure applied to the driven rollers 312b and 32b can be dispersed, It is possible to prevent the driven rotary shafts 31c and 32c from bending. Other configurations and operations are the same as those in the first embodiment.

<Third Embodiment>
A third embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the driven rollers 31b and 32b are disposed in the holders 31d and 32d, respectively. The biasing force of the protruding plate portion 38a of the shield member 36A is applied to the driven rollers 31b and 32b via the holders 31d and 32d, respectively.

  This will be specifically described. As shown in FIG. 11, the shield member 36 </ b> A is made of sheet metal obtained by performing predetermined processing on a metal plate such as phosphor bronze or stainless steel, and includes a case portion 37, a protruding plate portion 38 a, and a bent plate portion 39. Have. The case portion 37 surrounds the image sensor 33, and includes a substrate portion 37a and a pair of side plate portions 37b in which both end portions of the substrate portion 37a (in the sheet conveyance direction in the assembled state) are bent in the same direction. Projecting plate portions 38a are respectively formed at intermediate portions in the longitudinal direction (width direction in the assembled state) of the side plate portions 37b. The protruding plate portion 38a is formed to protrude toward the driven rollers 31b and 32b, respectively, in the assembled state of the shield member 36A with respect to the apparatus main body 11 (see FIG. 1).

  As shown in FIG. 12, a holder support formed in a rectangular parallelepiped shape and penetrating in the thickness direction of the sensor storage portion 35a on both sides in the sheet transport direction of the sensor storage portion 35a of the transport frame 35 to which the shield member 36A is assembled. Each portion 35f is formed. Holders 31d and 32d that support the driven rollers 31b and 32b are assembled to the holder support portion 35f. Further, the holder support portion 35 f is formed integrally with the transport frame 35.

  As shown in FIG. 13, the holders 31 d and 32 d are formed in a substantially rectangular parallelepiped shape, and bearing portions 31 d-1 and 32 d-1, hook portions 31 d-2 and 32 d-2 are provided at both ends in the assembled width direction. Is forming. The bearing portions 31d-1 and 32d-1 are formed so as to protrude in the direction toward the conveyance path 13 in the assembled state, and the hook portions 31d-2 and 32d-2 are opposite to the bearing portions 31d-1 and 32d-1. Is formed to protrude.

  Further, in the assembled state of the holders 31d and 32d, upstream of the sheet conveyance direction, sheet guide members 31d-3 and 32d-3 for filling a step in the conveyance path between the conveyance frame 35 and the driven rollers 31b and 32b. Respectively. As shown in FIGS. 11 and 13A, the sheet guide members 31d-3 and 32d-3 form a guide surface that is curved to protrude toward the conveyance path 13 toward the downstream side in the sheet conveyance direction, as shown in FIGS. ing. The sheet conveyed through the conveyance path 13 is guided to the nip portion N1 or N2.

  Further, as shown in FIG. 13B, partial spherical biasing receiving portions 31d-4 and 32d-4 are respectively formed on the bottom plate portion of the holders 31d and 32d opposite to the conveying path 13 so as to protrude. Yes. The urging receiving portions 31d-4 and 32d-4 abut against the protruding plate portion 38a of the shield member 36A in the assembled state, and receive the urging force of the protruding plate portion 38a.

  In the driven rollers 31b and 32b, the driven rotary shafts 31c and 32c are rotatably supported by the bearing portions 31d-1 and 32d-1 of the holders 31d and 32d, respectively. When the driven rollers 31b and 32b are assembled to the holders 31d and 32d, the operation is performed from the direction of the arrow b in FIG. Specifically, the driven rollers 31b and 32b are inclined and inserted into the holders 31d and 32d, and one ends of the driven rotating shafts 31c and 32c of the driven rollers 31b and 32d are inserted. To do. Thereafter, the other side of the driven rotating shafts 31c and 32c is inserted while the other bearing portions 31d01 and 32d-1 are bent outward. As a result, the driven rollers 31b and 32b are rotatably supported by the holders 31d and 32d, respectively.

  Next, the holders 31d and 32d supporting the driven rollers 31b and 32b as described above are assembled to the transport frame 35 as follows. First, the holders 31d and 32d are inserted into the holder support portion 35f from the bias receiving portions 31d-4 and 32d-4 in the direction of the arrow c in FIG. Then, the tips of the hook portions 31d-2 and 32-2 provided on the holders 31d and 32d come into contact with the peripheral edge of the opening of the holder support portion 35f, and enter the holder support portion 35f while bending inward.

  When the protrusions at the tips of the hook portions 31d-2 and 32-2 pass through the holder support portion 35f, the hook portions 31d-2 and 32-2 return to the original state from the bent state. Then, the protrusions at the tips of the hook portions 31d-2 and 32-2 are caught on the peripheral edge portion of the holder support portion 35f on the side where the protruding plate portion 38 is present, thereby preventing the hook portions 31d-2 and 32-2. Further, the holders 31d and 32d can move in a direction in which the holders 31d and 32d move far and away relative to the drive rollers 31a and 32a with respect to the holder support portion 35f.

  In this state, the urging receiving portions 31d-4 and 32d-4 elastically contact the protruding plate portion 38a of the shield member 36A assembled to the transport frame 35. Then, the driven rollers 31b and 32b are urged toward the driving rollers 31a and 32a via the holders 31d and 32d.

  Further, in the case of the present embodiment, instead of the platen roller 34, the second information reading unit reads the sheet information at a position facing the image sensor 33 which is the first information reading unit arranged on one side. A second image sensor 33A is provided. The configuration of the second image sensor 33A is the same as that of the image sensor 33. However, the second image sensor 33 </ b> A is fixed with respect to the frame constituting the conveyance path 13. A minute gap is formed between the contact glass 33e of the image sensor 33 and the contact glass 33e of the second image sensor 33A.

  Similarly to the platen roller 34, the second image sensor 33A configured as described above also serves as a regulating member that regulates the position of the sheet with respect to the image sensor 33. In the present embodiment, since the image sensor 33 and the second image sensor 33A are provided on both sides of the conveyance path 13, information on both sides of the sheet can be read by one sheet conveyance.

  With such a configuration, the driven rollers 31b and 32b are not loaded in the removal direction even when subjected to pressure, and do not come off during conveyance. Further, at the time of replacement, it can be easily removed by bending the bearing portions 31d-1 and 32d-1 of the holders 31d and 32d in the same manner as at the time of assembly. Further, if the holders 31d and 32d are made of a hard member having good sliding property such as POM (polyacetal), the rotational load of the driven rollers 31b and 32b can be reduced. Further, the single holders 31d and 32d serve as bearings on both sides of the shaft, and the durability of the apparatus can be improved. Further, by providing the holders 31d and 32d with the connection of the conveyance path 13 (sheet guide members 31d-3 and 32d-3), it is possible to fill the steps generated by arranging the holders 31d and 32d in the conveyance path 13. , Jam and so on. In the case of the present embodiment, by adopting the above-described configuration, it is possible to provide a driven unit that has excellent decomposability and does not shift during sheet conveyance with a small number of parts.

  It should be noted that the configurations of the above-described embodiments can be implemented by appropriately changing the combination. Also, the shape and structure of each part can be replaced with other shapes and structures having the same function. In each of the above-described embodiments, the first urging portion that urges the driven roller and the second urging portion that urges the image sensor are integrally formed. However, such a 1st biasing part and a 2nd biasing part may not be formed integrally with the shield member, and may be formed separately. For this reason, a 1st urging | biasing part and a 2nd urging | biasing part can also be integrally formed with plate members, such as a synthetic resin. In addition, the member facing the driving roller is not limited to the driven roller, and may have a shape (for example, a plate shape) other than the roller formed of a member whose surface is slippery.

1 Sheet information reader (scanner)
3 Information Reading Unit 31a Drive Roller 31b Follower Roller (opposing member)
31c driven rotary shaft 31d holder 32a drive roller 32b driven roller (opposing member)
32c driven rotation shaft 32d holder 33 image sensor (information reading means)
33A Second image sensor (second information reading means, regulating member)
34 Platen roller (regulating member)
35 transport frame 35f holder support 36 shield member (integrated biasing means)
37 Case part 37a Substrate part 38 Projection plate part (first urging part)
39 Bent plate part (second biasing part)
S sheet

Claims (7)

A driving roller for conveying the sheet along the conveying path;
A facing member that is disposed to face the driving roller and sandwiches the sheet with the driving roller;
An information reading unit that is adjacent to the opposing member in the sheet conveyance direction and reads information on the sheet;
An urging unit that urges the counter member toward the driving roller and urges the information reading unit toward the conveyance path ;
The integral urging means includes a first urging portion that urges the opposing member toward the drive roller, a second urging portion that urges the information reading means toward the conveyance path, and an elastic force. A shield member that is disposed so as to surround at least the periphery of the information reading means excluding the side facing the conveyance path and is grounded, and the first biasing portion And the second urging portion is formed integrally with the shield member.
A sheet information reading apparatus. The shield member is made of sheet metal and includes a case portion that surrounds the information reading unit, and a protrusion that constitutes the first urging portion that is formed to protrude from the case portion to the opposing member in the sheet conveyance direction. A plate portion, and a bent plate portion constituting the second urging portion formed by bending a part of the case portion toward the information reading means side,
The sheet information reading apparatus according to claim 1, wherein: A driving roller for conveying the sheet along the conveying path;
A facing member that is disposed to face the driving roller and sandwiches the sheet with the driving roller;
An information reading unit that is adjacent to the opposing member in the sheet conveyance direction and reads information on the sheet;
An urging unit that urges the counter member toward the driving roller and urges the information reading unit toward the conveyance path;
The integrated urging means includes a first urging portion that urges the facing member toward the drive roller, and a second urging portion that urges the information reading means toward the conveyance path. Have
The opposing member is a driven roller that rotates in contact with the drive roller,
The driven roller has a driven rotating shaft formed of a conductive member, and is grounded through the first urging portion.
A sheet information reading apparatus. A driving roller for conveying the sheet along the conveying path;
A facing member that is disposed to face the driving roller and sandwiches the sheet with the driving roller;
An information reading unit that is adjacent to the opposing member in the sheet conveyance direction and reads information on the sheet;
An urging unit that urges the counter member toward the driving roller and urges the information reading unit toward the conveyance path;
The integrated urging means includes a first urging portion that urges the facing member toward the drive roller, and a second urging portion that urges the information reading means toward the conveyance path. Have
The opposing member is a driven roller that rotates in contact with the drive roller,
The driven roller has a driven rotation shaft supported by the rotation support portion of the apparatus main body, and the driven rotation shaft is supported by the rotation support portion via the driven rotation shaft, and the driven rotation shaft is the first biasing force. Is urged toward the drive roller by being urged by the unit,
A sheet information reading apparatus. A conveyance frame which is fixed to the apparatus main body so as to surround the information reading unit and forms a conveyance path for conveying a sheet;
A shield member that is formed of an electrically conductive material having elasticity, and that is disposed so as to surround at least the periphery of the information reading unit excluding the side facing the conveyance path, and is grounded.
The shield member is fixed to the transport frame;
The sheet information reading apparatus according to claim 1 , wherein the sheet information reading apparatus is a sheet information reading apparatus. A driving roller for conveying the sheet along the conveying path;
A facing member that is disposed to face the driving roller and sandwiches the sheet with the driving roller;
An information reading unit that is adjacent to the opposing member in the sheet conveyance direction and reads information on the sheet;
An urging unit that urges the counter member toward the driving roller and urges the information reading unit toward the conveyance path;
The integrated urging means includes a first urging portion that urges the facing member toward the drive roller, and a second urging portion that urges the information reading means toward the conveyance path. Have
The opposing member is a driven roller that rotates in contact with the drive roller,
A holder for supporting the driven roller;
A holder support part that is formed integrally with a conveyance frame that constitutes a conveyance path for conveying a sheet and supports the holder;
The driven roller is urged via the holder by the first urging portion,
A sheet information reading apparatus. The information reading unit includes a first information reading unit disposed on one side of the conveyance path and a second information reading unit disposed to face the first information reading unit.
The sheet information reading apparatus according to claim 1 , wherein the sheet information reading apparatus is a sheet information reading apparatus.

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