JP4982227B2 - Image reading device - Google Patents

Description

  The present invention relates to an image reading apparatus such as a scanner that transports a document using a transport mechanism and reads an image of the document.

  When performing OCR processing for recognizing a character image of a document read by an image reading device such as a scanner, the image data is filed by aligning the position of the image data based on the contour of the document, the edge of the document, or a reference hole before processing. The standard must be clear.

  Since a normal document is white, if the background member such as a platen roller provided facing the reading sensor that reads the image is white, the color of the background image (background color) added around the scanned document image Becomes white, and the outline, edge, reference hole and the like of the read document are not emphasized.

  Therefore, an image reading device that switches the background color of a document to white or black at the time of scanning by color-coding the outer peripheral surface of a rotating member such as a platen roller into black and white in the circumferential direction and rotating the rotating member is proposed. (Patent Document 1).

  In this proposal, by switching the background color of the document to black, the outline, edges, holes, etc. of the document are emphasized, and when performing OCR processing, it is easy to file the image data by aligning the read data Become.

  On the other hand, in the case of a document with a low density of printing or printing and easy to transmit light, if the background color is black, the background color can be seen through, so the scanned image is subjected to printing or printing (black text) enhancement processing It becomes difficult to do. In this case, printing or printing can be emphasized by switching the background color of the document to white.

  On the other hand, in a double-sided document that easily transmits light, if the background color is white, the back side prints and prints are more visible, so the background color is black and the back side prints and prints are not emphasized. Can be. Thus, the background color is properly used depending on the original to be read. The rotating member rotates when the background color is switched, but is stopped so that the background color is not switched during document reading.

Further, in general, in an image reading apparatus that reads both sides by a single document conveyance, two reading sensors for the front side and the back side are provided, and the reading sensor is opposed to the reading position of each reading sensor. A background member such as a platen roller to be in close contact with is disposed.
Japanese Patent No. 2761736

  By the way, in order to realize the switching of the background color of an original in an image reading apparatus equipped with a rotating member such as a platen roller, for example, a color different from the ground color is applied to a rotating member whose ground color is white or black. A method of attaching a sheet-like member having a color different from the ground color is conceivable.

  However, since the original rubs the painted surface of the rotating member, the coating becomes thin when used for a long period of time, and the color of the rotating member can be seen through and the hue changes. In addition, when there is uneven color of the coating, there arises a problem that the hue becomes uneven.

  Also, when a sheet-like member is attached to the rotating member, it is difficult to attach a sheet-like member having a sufficient thickness that does not transmit light, and the end of the sheet-like member may be gradually peeled off. If the sheet-like member is peeled off, the rotation of the rotating member is hindered, causing a failure. Further, since a thin sheet-like member that can be easily attached is easy to transmit light, the color of the rotating member can be seen through, and there is a disadvantage that the desired color is not achieved.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image reading apparatus capable of enhancing the durability of a rotating member having regions with different brightness in the circumferential direction.

  Another object of the present invention is to provide an image reading apparatus including a rotating member that can maintain a distance from the reading sensor with high accuracy.

  Another object of the present invention is to provide an image reading apparatus that can be easily replaced even if the rotating member is damaged.

To achieve the above object, an image reading apparatus of the present invention, Ru is disposed a reading sensor for reading an image of a document conveyed on the conveying path, at a position facing each other across the conveying path relative to said read sensor And a rotating member that stops at the time of image reading of the document by the reading sensor and forms a background of the document, and the rotating member is formed by combining at least two arc tube members made of materials of different colors. And the background color of the document is changed by a rotation operation .

  The image reading apparatus of the present invention is characterized in that a substantially white or transparent sheet-like member is attached to the outer periphery of a substantially white arc-shaped member, or a substantially white or transparent coating film is formed.

  In addition, the image reading apparatus of the present invention includes a shaft member serving as a central axis of the rotating member.

  The image reading apparatus of the present invention includes a rotating member unit in which a rotating member, a holding member, and a conveyance guide are combined together.

  According to the present invention, since the rotating member is formed by combining the circular cylindrical members having different brightness, the surface color does not change even if the document is rubbed against the surface of the rotating member. Thereby, durability of a rotating member improves and it becomes possible to use it for a long period of time.

  Moreover, since a substantially white or transparent sheet-like member is attached to the outer periphery of the substantially white arc-shaped member or a substantially white or transparent coating film is formed, it is possible to maintain a uniform color for a longer period of time. .

  Further, since the rotating member unit is used, or the shaft member is provided at the center of the rotating member, the reading sensor and the rotating member can be made to face each other with high accuracy. In addition, since the rotating member can be replaced as a rotating member unit, the replacement can be easily performed even if a failure occurs.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 2 is a simplified diagram for explaining the apparatus configuration of the image reading apparatus according to the first embodiment of the present invention.

  As shown in FIG. 2, the image reading apparatus moves up until the document table 7 on which the document 8 is loaded contacts the pickup roller 6, and the document 8 picked up by the pickup roller 6 is fed by the feeding roller 4. Is done.

  When two or more documents 8 are simultaneously picked up by the pickup roller 6, the documents 8 are separated one by one by the separation roller 11 and fed. Then, the fed image of the document 8 is read by the reading sensor 1. A platen roller (rotating member) 10 is provided at a position facing the reading sensor 1 via a certain gap.

  The platen roller 10 has a cylindrical shape, and the half circumference area of the outer peripheral surface is a black part, and the remaining half circumference area is a white part. Normally, the platen roller 10 is stopped and rotates when the background color of the document 8 is switched. Depending on the type of document read by the reading sensor 1, the rotation of the platen roller 10 can be controlled to switch the background color of the document 8 to black or white.

  For example, in the case of a paper document with low density of printing or printing and easy to see through, the platen roller 10 is rotated so that the white portion of the platen roller 10 faces the reading sensor 1, and the background color of the document is white. Switch to, and emphasize printing and printing characters.

  Further, in the case of a paper document that is easily printed on both sides, the platen roller 10 is rotated so that the black portion of the platen roller 10 faces the reading sensor 1 and the background color of the document is switched to black. Eliminate the reflection.

  The document 8 whose image has been read by the reading sensor 1 is transported by the transport roller 3 and discharged onto the paper discharge tray 9 by the paper discharge roller 5. When all the documents 8 loaded on the document table 7 are fed, the document table 7 is lowered and returned to the home position.

  Note that the upper unit 2 having the conveyance roller 3, the feeding roller 4, the reading sensor 1, and the platen roller 10 can be rotated with respect to the lower unit 12 via a hinge 13 and can open and close the conveyance path. By rotating the upper unit 2 with respect to the lower unit 12 to open the conveyance path, the conveyance roller 3, the platen roller 10, the reading sensor 1, the conveyance path, and the document jammed in the conveyance path are removed. be able to.

  The rotation operation of the upper unit 2 can be detected by using an opening / closing detection sensor (not shown), and the control means (not shown) indicates that the upper unit 2 has been returned to its original position and the conveyance path has been closed. Is checked and control is performed to enter the feed standby mode.

  Next, the platen roller 10 will be described with reference to FIG. FIG. 1 is an exploded perspective view of the platen roller 10.

  As shown in FIG. 1, the platen roller 10 includes a semi-cylindrical white member (arc cylinder member) 14 and a semi-cylindrical black member (arc cylinder member) 15.

  A boss 14a projects in the axial direction at one end (left end in the figure) of the white member 14, and a hole substantially concentric with the boss 14a is formed in the other end (right end in the figure) in the axial direction. 14e is provided. Further, a fitting convex portion 14b, a hooking concave portion 14c, and a fitting convex portion 14d are disposed at predetermined intervals in the axial direction at a substantially central portion of the inner peripheral surface of the white member 14 in the circumferential direction.

  On the other hand, a hole 15a into which the boss 14a is fitted is provided at one end portion (left end portion in the figure) of the black member 15, and the other end portion (right end portion in the figure) in the axial direction is fitted into the hole 14e. A boss 15e is provided.

  Further, in the substantially central portion of the inner peripheral surface of the black member 15 in the circumferential direction, there is a fitting recess 15b fitted into the tip of the fitting convex portion 14b, and a hooking portion 15c hooked in the axial direction by the hooking concave portion 14c. And the fitting recessed part 15d fitted by the front-end | tip part of the fitting convex part 14d is arrange | positioned at predetermined intervals in the axial direction.

  In order to combine the white member 14 and the black member 15, first, the fitting concave portion 15b, the hooking portion 15c of the black member 15 and the fitting convex portion 14b, the hooking concave portion 14c and the fitting convex portion 14d of the white member 14 are combined. The white member 14 and the black member 15 are aligned in the radial direction in a state where the fitting convex portion 14d is shifted to one end side (left end side in the figure) in the axial direction.

  Next, the black member 15 is slid relative to the white member 14 toward the other end side in the axial direction (the right end side in the figure), so that the boss 14a of the white member 14 is axially inserted into the hole 15a of the black member 15. The boss 15e of the black member 15 is fitted in the hole 14e of the white member 14 in the axial direction.

  At the same time, the fitting recesses 15b, 15d of the black member 15 are fitted in the distal ends of the fitting projections 14b, 14d of the white member 14, and the hooking portion 15c of the black member 15 is hooked to the white member 14. The recess 14c is fitted in the axial direction.

  Thereby, the white member 14 and the black member 15 are combined, and the cylindrical platen roller 10 is formed. In addition, after combining in this way, the white member 14 and the black member 15 are prevented from coming off by a snap fit (not shown) or the like so as not to come off. Moreover, the uneven | corrugated fitting structure of the white member 14 and the black member 15 is not specifically limited, A various uneven | corrugated fitting structure is employable.

  FIG. 3 is a perspective view of a platen roller unit (rotating member unit) 22 including the platen roller 10, the holding members 16 and 17, and the conveyance guide 18.

  The holding members 16 and 17 hold a conveyance guide 18 that guides the document 8 being conveyed, and rotatably hold both end portions in the axial direction of the platen roller 10 via the bearing portions 16b and 17b.

  After the platen roller unit 22 is mounted on the main body device, the reading sensor 1 (see FIG. 2) abuts against the spacer portions 16a and 17a of the holding members 16 and 17, so that the platen roller 10 and the reading sensor 1 are in contact with each other. A predetermined gap is secured. The spacer portions 16a and 17a may be provided not on the platen roller unit 22 side but on the reading sensor 1 side.

  FIG. 4 is a perspective view showing a state when the platen roller unit 22 is attached to the main body apparatus.

  To attach the platen roller unit 22 to the main unit, first, the upper unit 2 is opened with respect to the lower unit 12, as shown in FIG. On both side walls in the width direction orthogonal to the conveyance direction of the document 8 of the upper unit 2, mounting portions 23 that are notched in a substantially U shape are provided.

  Then, the platen roller unit 22 is moved in the axial direction (the arrow direction in the figure) in a state where the conveyance guide 18 is disposed above and the axis of the platen roller 10 is disposed in the width direction of the upper unit 2. The holding members 16 and 17 are partially inserted into the mounting portions 23 of the upper unit 2.

  In this state, the platen roller unit 22 is attached to the upper unit 2 by rotating the platen roller unit 22 around the axis of the platen roller 10.

  Specifically, as shown in FIG. 5, a protrusion 24 is provided above the mounting portion 23 of the upper unit 2, and the bearing portions 16 b and 17 b provided on the holding members 16 and 17 of the platen roller unit 22 The arm portions 16f are respectively formed.

  The arm portion 16f is formed of a flexible member, and the arm portion 16f is provided with a latching portion 16e that is detachably latched on the protrusion 24 of the upper unit 2.

  Then, as shown in FIGS. 5 and 6, the bearing portions 16b and 17b of the platen roller unit 22 are inserted into the mounting portions 23 and 23 of the upper unit 2 with the conveying guide 18 disposed upward (see FIG. 5). 6).

  In this state, when the platen roller unit 22 is rotated 90 ° around the axis of the platen roller 10 (in the direction of the arrow in FIG. 6), the arm 16f bends and gets over the projection 24, and the latching portion 16e is fitted into the projection 24 ( (See FIG. 7). Thereby, the platen roller unit 22 can be easily attached to the upper unit 2.

  In this attached state, a gear (not shown) provided on the platen roller 10 and a drive unit (not shown) provided on the apparatus main body are connected. Based on the operation by the user, the control unit controls the driving of the driving unit, so that the platen roller 10 rotates, and the white member 14 or the black member 15 is disposed to face the reading sensor 1, and the document 8 The background color is switched to white or black.

  On the other hand, when removing the platen roller unit 22 from the upper unit 2, the arm 16 is bent and the latching portion 16 e is removed from the protrusion 24, and then the platen roller unit 22 is subjected to a process reverse to the attaching process described above. Can be easily removed from the upper unit 2. The platen roller unit 22 may be detachably attached to the lower unit 12 in the same manner as described above.

  As described above, in this embodiment, since the platen roller 10 is formed by combining the semi-cylindrical white member 14 and the semi-cylindrical black member 15, the document 8 rubs against the surface of the platen roller 10. However, the surface color does not change or the surface does not peel off.

  Thereby, the durability of the platen roller 10 is improved, and the platen roller 10 can be used for a long time.

  A sheet-like member such as a substantially white tape may be fixed on the outer peripheral surface of the substantially white semicylindrical member 14 using an adhesive, an adhesive, or the like. Even if the sheet-like member is thin, the whiteness does not decrease because the substantially white semi-cylindrical member 14 is provided on the base, and the wear resistance is superior to the semi-cylindrical member 14. Instead of fixing the substantially white sheet-like member, a substantially white coating film may be formed. Even if this coating film has uneven color, since the substantially white semi-cylindrical member 14 is present on the base, the whiteness is uniform. Also, the wear resistance is superior to the semi-cylindrical member 14. The same effect is obtained even if the sheet-like member fixed to the platen roller 10 and the coating film to be formed are transparent.

  Moreover, since the platen roller 10 can be assembled by moving the black member 15 relative to the white member 14 in the axial direction, the assembly work of the platen roller 10 can be facilitated.

  Further, since the platen roller unit 22 having the platen roller 10, the holding members 16 and 17, and the conveyance guide 18 can be easily attached to and detached from the upper unit 2, an operation for replacing the platen roller 10 according to the life or the like, The operation | work which cleans the roller 10 can be performed efficiently.

  Further, since the platen roller 10 and the conveyance guide 18 for guiding the conveyed document 8 are unitized as a unit, the relative position between the platen roller 10 and the conveyance guide 18 can be maintained with high accuracy.

  As a result, the gap between the platen roller 10 and the reading sensor 1 can be kept with a minimum accuracy and the reading image quality can be improved.

  Next, an image reading apparatus according to the second embodiment of the present invention will be described with reference to FIG. FIG. 8 is an exploded perspective view for explaining the platen roller attached to the image reading apparatus according to the second embodiment of the present invention. Note that the description of the same parts as those in the first embodiment is omitted.

  In this embodiment, an image reading apparatus capable of preventing the platen roller from warping and keeping the gap between the platen roller and the reading sensor constant will be described.

  As shown in FIG. 8, the platen roller (rotating member) 25 includes a semi-cylindrical white member (arc cylinder member) 26 and a semi-cylindrical black member (arc cylinder member) 27.

  For example, cylindrical fitting portions 26a and 26e and a fitting portion 26c projecting in the same axial direction are provided coaxially at both axial end portions and the axial central portion of the white member 26, respectively.

  For example, cylindrical fitted portions 27a and 27e and fitted portions 27c in which the fitted portions 26a and 26e and the fitted portions 26c are fitted in the axial direction are respectively provided at both axial ends and the central portion of the black member 27. It is provided on the same axis.

  In order to combine the white member 26 and the black member 27, first, the fitting portions 26a, 26e and the fitting portion 26c of the white member 26 are axially arranged with respect to the fitting portions 27a and 27e and the fitting portion 27c of the black member 27. The white member 26 and the black member 27 are aligned in the radial direction while being shifted to one end side (left end side in the figure).

  Next, the white member 26 is slid relative to the black member 27 toward the other end side in the axial direction (the right end side in the figure), so that the fitting portions 26 a and 26 e and the fitting portion 26 c of the white member 26 become the black member 27. The fitting parts 27a and 27e and the fitting part 27c are fitted in the axial direction. Thereby, the white member 26 and the black member 27 are combined. Note that, after such a combination, the white member 26 and the black member 27 are prevented from being detached by a snap fit (not shown) so that the white member 26 and the black member 27 are not detached.

  Thereafter, the shaft 29 is inserted into the inner peripheral portions of the fitting portions 26a, 26c, and 26e of the white member 26, whereby the cylindrical platen roller 25 in which the shaft 29 protrudes at both ends in the axial direction is formed. In addition, the uneven | corrugated fitting structure of the white member 26 and the black member 27 is not specifically limited, A various uneven | corrugated fitting structure is employable.

  A platen roller unit (rotating member unit) (not shown) is configured by the cylindrical platen roller 25 having shafts 29 protruding at both ends in the axial direction, the holding members 16 and 17 shown in FIG.

  In this platen roller unit, shafts 29 projecting from both ends in the axial direction of the platen roller 25 via bearing portions 16b and 17b of the holding members 16 and 17 are rotatably supported. Note that the shaft 29 may be fixed to the holding members 16 and 17 and the platen roller 25 may be rotatably supported with respect to the shaft 29.

  As described above, in this embodiment, the fitting portions 26a, 26e, and 26c of the white member 26 are fitted in the fitting portions 27a, 27e, and 27c of the black member 27 in the axial direction, and then the fitting portions of the white member 26 are fitted. A shaft 29 is inserted through the inner peripheral portions of 26a, 26c, and 26e.

  Accordingly, even if the platen roller 25 is warped, the warp can be corrected, and the shape accuracy of the platen roller 25 can be improved. As a result, the gap between the reading sensor 1 and the platen roller 25 can be kept constant over the entire length of the reading sensor 1, and the reading image quality is improved. Other configurations and operational effects are the same as those of the first embodiment.

  In addition, this invention is not limited to what was illustrated to the said embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.

  For example, in the above-described embodiment, the semi-cylindrical white member and the black member divided into two at the 180 ° position in the circumferential direction are illustrated, but the division position is not particularly limited, and at any position in the circumferential direction. You may make it combine the circular arc cylinder member divided | segmented into 2 or 3 or more.

  Moreover, in the said embodiment, although the white member and the black member were illustrated as an arc cylinder member from which lightness differs, it is not limited to this, It is trying to combine arc cylinder members, such as other arbitrary colors, light gray, and dark gray It may be.

  Also, as shown in FIG. 9, the portion of the outer peripheral surface of the platen roller 10 that faces the reading sensor 1 when stationary. You may make it the shape retreated in the radial direction rather than the other cylindrical outer peripheral surface. By doing so, contact between the outer peripheral surface of the platen roller 10 and the original can be prevented, and the durability of the platen roller 10 is improved.

FIG. 2 is an exploded perspective view of a platen roller incorporated in the image reading apparatus according to the first embodiment of the present invention. 1 is a simplified diagram for explaining a device configuration of an image reading apparatus according to a first embodiment of the present invention. It is a perspective view for demonstrating a platen roller unit. It is a perspective view which shows a mode at the time of attaching a platen roller unit to a main body apparatus. It is a figure for demonstrating the example of attachment of a platen roller unit. It is a figure for demonstrating the example of attachment of a platen roller unit. It is a figure for demonstrating the example of attachment of a platen roller unit. It is a disassembled perspective view of the platen roller incorporated in the image reading apparatus which is the 2nd Embodiment of this invention. It is a figure which shows the modification of the platen roller of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reading sensor 2 Upper unit 3 Conveying roller 4 Feeding roller 5 Paper discharge roller 6 Pickup roller 7 Document base 8 Document 9 Paper discharge tray 10 Platen roller 11 Separating roller 12 Lower unit 13 Hinge 14 White member 14a Boss 14b Insertion convex part 14c Hooking concave portion 14d Fitting convex portion 14e Hole 15 Black member 15a Hole 15b Fitting concave portion 15c Hooking portion 15d Fitting concave portion 15e Boss 16 Holding member 16a Spacer portion 17 Holding member 17a Spacer portion 18 Transport guide 16b Bearing portion 16e Hooking portion 16f Arm Part 17b bearing part 22 platen roller unit 23 mounting part 25 platen roller 26 white member 26a fitting part 26c fitting part 26e fitting part 27 black member 27a fitting part 27c fitting part 27e fitting part 29 shaft

Claims (11)

A reading sensor for reading an image of a document conveyed on the conveyance path;
Comprising a rotating member that forms the background of the document is stopped at the time of image reading of the document by Rutotomoni said reading sensor is arranged at a position facing each other across the conveying path relative to said read sensor, and
2. The image reading apparatus according to claim 1, wherein the rotating member is formed by combining at least two arc tube members made of materials of different colors and changes the background color of the document by a rotating operation .   The image reading apparatus according to claim 1, wherein a shaft member is inserted through a portion where the two arc tube members are fitted to each other.   The image reading apparatus according to claim 2, wherein the shaft member passes through a rotation axis of the rotation member and supports the rotation member.   A rotating member unit in which the rotating member, the shaft member, a transport guide that guides a document to be transported in the transport direction, and a holding member that holds both ends of the shaft member are integrally combined is detachably disposed. The image reading apparatus according to claim 2, wherein the image reading apparatus is an image reading apparatus. At least one fitting portion is provided on the inner peripheral side of one of the two arc tube members, and a fitting portion corresponding to the fitting portion is provided on the other arc tube member,
The image reading apparatus according to claim 1, wherein at least one of the fitting portions is disposed at a position including a rotation center of the rotating member. At least one fitting portion is provided on the inner peripheral side of one of the two arc tube members, and a fitting portion corresponding to the fitting portion is provided on the other arc tube member,
At least one of the fitting portions is disposed at a position including the rotation center of the rotating member, the shaft member is fitted into at least one of the fitting portions, and at least of the fitting portion into which the shaft member is fitted. The image reading apparatus according to claim 2, wherein one is disposed in the vicinity of a central portion in the axial direction of the rotating member.   A rotating member unit in which the rotating member, a conveyance guide that guides a document to be conveyed in a conveying direction, and a holding member that holds both ends of the rotating member are integrally combined is detachably disposed. The image reading apparatus according to claim 1.   8. The image reading apparatus according to claim 1, wherein one of the two arc tube members is substantially black, and the other arc tube member is substantially white. 9. .   The image reading apparatus according to claim 8, wherein a substantially white or transparent sheet-like member is installed along an outer periphery of the substantially white arc-shaped member.   The image reading apparatus according to claim 8, wherein a substantially white or transparent coating film is formed on an outer periphery of the substantially white arcuate member.   The image reading apparatus according to any one of claims 1 to 10, wherein the two arc tube members have a substantially semi-cylindrical shape.

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