Image reading device and image forming device

Abstract

The present invention provides an image reading device and an image forming device. The image reading device includes: a manuscript table for placing a manuscript; a reading unit including a light source and a reading unit, the light source is used to illuminate the manuscript, and the reading unit is used to read the image on the manuscript at a reading position; a conveying unit is used to convey the manuscript to the reading unit; and a facing plate, which is located on the side of the manuscript opposite to the manuscript table at the reading position, wherein the facing plate is provided with a paper limiting portion, which is located between the manuscript table and the facing plate and is used to limit the distance between the manuscript and the facing plate. The image forming device includes: an image reading device for reading an image on a manuscript; and an image forming mechanism for forming the image read by the image reading device on a paper.

Description

Technical Field

[0001] The present invention relates to the field of printing technology, and particularly to an image reading device and an image forming device including the image reading device. Background Art

[0002] During the conveyance of the original document, it may be inclined. When reading the original document, electronic inclination correction needs to be performed on the original document. Electronic inclination correction detects the inclination amount of each original document by using whether the shadow generated by the original document and the background plate (opposing plate) is inclined, and then performs inclination correction. When developing the software algorithm, there are relevant requirements for the shadow tone. Usually, the original document is divided into four sections, and within at least 50% of the width of each section of the original document, the gradation of the shadow needs to be ensured to be above 25.

[0003] However, in the current ADF machines equipped with electronic inclination correction, there may be a case where the color gradation difference generated by the shadow at the leading end of the original document is below gradation 25, which does not meet the requirement of gradation above 25 specified in the software. Instead, the image on the original document is misrecognized as a shadow, resulting in abnormal images. The main reasons for this phenomenon are that the warping of the original document causes the original document to contact the opposing plate, making it difficult to generate the shadow of the original document. In addition, the distance between the opposing plate and the original document table is relatively small, making it easier for the original document to contact the opposing plate, thus resulting in poor electronic inclination correction effect. Summary of the Invention

[0004] Embodiments of the present invention provide an image reading device and an image forming device, which improve the electronic inclination correction ability by avoiding contact between the original document and the opposing plate.

[0005] According to an aspect of the present invention, there is provided an image reading device. The image reading device includes: an original document table for placing the original document; a reading unit including a light source and a reading portion, the light source being used to irradiate the original document, and the reading portion being used to read the image on the original document at a reading position; a conveyance unit for conveying the original document to the reading unit; and an opposing plate located on the side of the original document opposite to the original document table at the reading position, wherein the opposing plate is provided with a paper limiting portion located between the original document table and the opposing plate for limiting the distance between the original document and the opposing plate.

[0006] Optionally, the surface of the opposing plate facing the original document table is white.

[0007] Optionally, the ratio of the width of the paper limiting portion to the width of the opposing plate is less than 50%, and within a predetermined distance on both sides of the center line of the opposing plate parallel to the paper conveyance direction, the ratio of the width of the paper limiting portion to the width of the opposing plate does not exceed 50%.

[0008] Optionally, the paper limiting part is a plurality of convex ribs formed on the opposing plate, and the surfaces of the plurality of convex ribs facing the original document table are white.

[0009] Optionally, the plurality of convex ribs are distributed in an area 5 mm to 30 mm away from the center line on both sides of the center line of the opposing plate along the direction parallel to the paper conveyance direction.

[0010] Optionally, the height of the plurality of convex ribs is 0.1 to 0.5 mm, and the width is 1 to 5 mm.

[0011] Optionally, the opposing plate is further provided with a frame, the surface of the frame facing the original document table is located between the original document table and the opposing plate, and the paper limiting part is a plurality of white films mounted on the surface of the frame facing the original document table.

[0012] Optionally, the conveyance unit includes an upper guide rail part and a contact film connected to the upper guide rail part, and the contact film is in contact with the original document table so that the original document is conveyed between the contact film and the original document table.

[0013] Optionally, the conveyance unit includes an upper guide rail part and a rotatable guide rail connected to the upper guide rail part, and the rotatable guide rail is in contact with the original document table so that the original document is conveyed between the rotatable guide rail and the original document table.

[0014] Optionally, the opposing plate is further provided with a height adjustment assembly for adjusting the height of the frame.

[0015] Optionally, the frame includes a plurality of frame parts, and two adjacent frame parts are connected by a connecting member.

[0016] Optionally, the height adjustment assembly includes a plurality of adjustment parts, and the height of the frame is adjusted by changing the number of the plurality of adjustment parts.

[0017] According to another aspect of the present invention, an image forming apparatus is provided. The image forming apparatus includes: an image reading device for reading an image on an original document; and an image forming mechanism for forming the image read by the image reading device on paper.

[0018] Compared with the prior art, the technical solutions of the embodiments of the present invention have the following beneficial effects:

[0019] According to an embodiment of the present invention, the opposing plate is provided with a paper restricting portion, which is located between the original document table and the opposing plate and is used to restrict the distance between the original document and the opposing plate. Through the paper restricting portion, contact between the original document and the opposing plate can be avoided, ensuring that the leading end of the original document can form a shadow on the opposing plate, thereby accurately determining the inclination amount of each original document, and then performing inclination correction, improving the electronic inclination correction ability.

[0020] Furthermore, the ratio of the width of the paper restricting portion to the width of the opposing plate is less than 50%. Further, within a predetermined distance on both sides of the center line of the opposing plate parallel to the paper conveyance direction, the ratio of the width of the paper restricting portion to the width of the opposing plate does not exceed 50%. By restricting the width of the paper restricting portion, the inclination amount of the leading end of the original document can be accurately determined, and then inclination correction can be performed, improving the electronic inclination correction ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Other features and advantages of the present invention will be better understood through the following alternative embodiments described in detail in conjunction with the drawings, where the same reference numerals represent the same or similar components, and among them:

[0022] Figure 1 Shows a partial structural cross-sectional schematic diagram of an image reading device according to an embodiment of the present invention.

[0023] Figure 2 Shows a schematic structural diagram of the opposing plate of an image reading device according to an embodiment of the present invention.

[0024] Figure 3 Shows a schematic structural diagram of the opposing plate of an image reading device according to another embodiment of the present invention.

[0025] Figure 4 Shows a schematic structural diagram of the conveyance unit of an image reading device according to another embodiment of the present invention.

[0026] Figure 5 Shows a schematic structural diagram of the conveyance unit of an image reading device according to another embodiment of the present invention.

[0027] Figure 6 Shows a schematic structural diagram of the height adjustment device of the frame of an image reading device according to an embodiment of the present invention.

[0028] Figure 7 Shows a schematic structural diagram of an image forming device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The implementation and use of the embodiments will be discussed in detail below. However, it should be understood that the specific embodiments discussed are merely exemplary illustrations of specific ways of implementing and using the present invention, rather than limiting the scope of the present invention. When describing the structural positions of various components, expressions of directions such as up, down, top, bottom, etc. are not absolute but relative. When the components are arranged as shown in the figures, these expressions of directions are appropriate, but when the positions of the components in the figures change, these expressions of directions also change accordingly.

[0030] As described in the background art, for the color tone difference generated by the shadow at the leading end of the original document, there may be a case where the tone is below 25, which does not meet the software-specified tone of 25 or more. Instead, the image on the original document is misrecognized as a shadow, and thus an abnormal image appears. The main reason for this phenomenon is that the warping of the original document causes the original document to contact the opposing plate, making it difficult to generate the shadow of the original document. In addition, the distance between the opposing plate and the original document table is relatively small, making it easier for the original document to contact the opposing plate, resulting in a poor effect of electronic tilt correction.

[0031] To this end, an embodiment of the present invention provides an image reading device. The image reading device includes: an original document table for placing the original document; a reading unit including a light source and a reading portion, the light source being used to irradiate the original document, and the reading portion being used to read the image on the original document at a reading position; a conveying unit for conveying the original document to the reading unit; and an opposing plate, at the reading position, on the side of the original document opposite to the original document table, the surface of the opposing plate facing the original document table being white, wherein the opposing plate is provided with a paper limiting portion located between the original document table and the opposing plate for limiting the distance between the original document and the opposing plate.

[0032] Through the paper limiting portion, it is possible to prevent the original document from contacting the opposing plate, ensuring that the leading end of the original document can form a shadow on the opposing plate, thereby accurately determining the tilt amount of each original document, and then performing tilt correction, improving the electronic tilt correction ability.

[0033] As Figure 1As shown, according to an embodiment of the present invention, the image reading device 100 includes a document table 10, a reading unit 20, a conveying unit 30, and an opposing plate 40. The document table 10 is used for placing a document; the reading unit 20 includes a light source (not shown in the figure) and a reading portion 21. The light source is used for irradiating the document, and the reading portion 21 is used for reading the image on the document at a reading position. The conveying unit 30 is used for conveying the document to the reading unit 20; the opposing plate 40 is located on the side of the document opposite to the document table at the reading position, that is to say, the document table 10 and the opposing plate 40 are respectively located on both sides of the document. The surface of the opposing plate 40 facing the document table 10 is white. The opposing plate 40 serves as the background of the document. The light source irradiates the document, and a shadow of the document is formed on the opposing plate 40.

[0034] Wherein, the opposing plate 40 is provided with a paper restricting portion. The paper restricting portion is located between the document table 10 and the opposing plate 40 and is used for restricting the distance between the document and the opposing plate 40, thereby preventing the document from contacting the opposing plate 40 and affecting the formation of the shadow of the document.

[0035] The ratio of the width of the paper restricting portion to the width of the opposing plate 40 is less than 50%. And within a predetermined distance on both sides of the center line of the opposing plate 40 parallel to the paper conveying direction, the ratio of the width of the paper restricting portion to the width of the opposing plate 40 does not exceed 50%. For example, in order to ensure that the leading edge of the document forms a shadow on the opposing plate 40, if the smallest paper to be conveyed is A5 paper with a size of 148×210mm, then within a distance of 74mm on both sides of the center line of the opposing plate 40 parallel to the paper conveying direction, the ratio of the width of the paper restricting portion to the width of the opposing plate 40 does not exceed 50%. Here, the width of the opposing plate 40 refers to the size of the opposing plate 40 as seen along the paper conveying direction, and can also be understood as the size of the opposing plate 40 in the plane parallel to the paper conveying direction and perpendicular to the paper conveying direction.

[0036] As Figure 2 shown, in some embodiments, the paper restricting portion is a plurality of convex ribs 41 formed on the opposing plate 40. The surface of each convex rib 41 facing the document table 10 is white. If it is other colors, when the paper is thin, it may be mistaken for an image through the paper. For example, the surface of each convex rib 41 facing the document table 10 is spray-coated with white to ensure whiteness. In this way, even if the document is warped, it will only contact the convex ribs 41, thereby ensuring that the leading edge of the document forms a shadow on the opposing plate 40.

[0037] In some embodiments, a plurality of ribs 41 are distributed in a region on both sides of the center line of the opposing plate 40 parallel to the paper conveyance direction and at a distance of 5 mm to 30 mm from the center line. For example, the plurality of ribs 41 are symmetrically arranged on both sides of the center line of the opposing plate 40, and there is the same spacing between adjacent ribs 41. In other embodiments, the plurality of ribs 41 may be randomly distributed, and there are different spacings between adjacent ribs 41. In some embodiments, the height of the plurality of ribs 41 is 0.1 to 0.5 mm, and the width is 1 to 5 mm. For example, the height of the plurality of ribs 41 is 0.2 mm, and the width is 2 mm. The plurality of ribs 41 may have the same or different heights, and may have the same or different widths. The sum of the widths of the plurality of ribs 41 is less than 50% of the width of the opposing plate 40, and within a distance of 74 mm on both sides of the center line in the width direction of the opposing plate 40, the sum of the widths of the plurality of ribs 41 does not exceed 50% of the width of the opposing plate 40.

[0038] As Figure 3 shown, in some embodiments, the opposing plate 40 is further provided with a frame 50. The surface of the frame 50 facing the original document table 10 is located between the original document table 10 and the opposing plate 40. The paper restricting portion is a plurality of white films 42 mounted on the surface of the frame 50 facing the original document table 10. There may be the same or different spacings between adjacent white films 42. For example, the plurality of white films 42 are evenly arranged along the frame 50. Since a plurality of white films 42 are provided on the surface of the frame 50 facing the original document table 10, the leading end of the original document cannot contact the opposing plate 40, ensuring that the leading end of the original document effectively forms a shadow on the opposing plate 40 and improving the electronic tilt correction effect.

[0039] As Figure 4 shown, in some embodiments, the conveyance unit 30 includes an upper guide rail portion 31 and a contact film 32 connected to the upper guide rail portion 31. One end of the contact film 32 is connected to the upper guide rail portion 31, and the other end is in contact with the original document table 10. The contact film 32 is very light in weight and is generally made of plastic, resin or other materials. When the original document is conveyed through the upper guide rail portion 31 of the conveyance unit 30, the leading end of the original document will push the contact film 32 to move slightly upward, so that the original document is conveyed between the contact film 32 and the original document table 10. When the entire original document passes through the contact film 32, the contact film 32 continues to be in contact with the original document table 10. The leading end of the original document is prone to upward warping during the conveyance process. The contact film 32 can press down the leading end of the original document, thereby preventing the leading end of the original document from contacting the opposing plate 40, ensuring that the leading end of the original document effectively forms a shadow on the opposing plate 40, and improving the electronic tilt correction effect.

[0040] As Figure 5As shown, in some embodiments, the conveying unit 30 includes an upper guide rail portion 31 and a rotatable guide rail 33 connected to the upper guide rail portion 31. One end of the rotatable guide rail 33 is rotatably connected to the upper guide rail portion 31, for example, by a rotating shaft, and the other end is in contact with the original document table 10. After the original document is conveyed by the upper guide rail portion 31 of the conveying unit 30, the leading end of the original document will push the rotatable guide rail 33 to rotate slightly upward, so that the original document is conveyed between the rotatable guide rail 33 and the original document table 10. When the entire original document passes through the rotatable guide rail 33, the rotatable guide rail 33 rotates back due to its own gravity, so as to continue to be in contact with the original document table 10. During the conveying process of the original document, the problem that the leading end of the original document warps upward easily occurs. The rotatable guide rail 33 can press down the leading end of the original document, thereby avoiding the contact between the leading end of the original document and the opposing plate 40, ensuring that the leading end of the original document effectively forms a shadow on the opposing plate 40, and improving the electronic tilt correction effect.

[0041] In some embodiments, the frame 50 includes a plurality of frame parts 51, as Figure 3 shown, two adjacent frame parts 51 are connected by a connecting member. By dividing the frame 50 of the opposing plate 40 into two or more segments along the length direction, the length of each segment of the frame is shortened, so that the warping degree of the opposing plate can be well guaranteed, thereby avoiding the contact between the leading end of the original document and the opposing plate, ensuring that the leading end of the original document effectively forms a shadow on the opposing plate, and improving the electronic tilt correction effect.

[0042] As Figure 6 shown, in some embodiments, the opposing plate 40 is further provided with a height adjustment assembly 60 for adjusting the height of the frame 50. In some embodiments, the height adjustment assembly 60 includes a plurality of adjustment parts, and the height of the frame is adjusted by changing the number of the plurality of adjustment parts.

[0043] As Figure 6 shown, the height adjustment assembly 60 includes a plurality of washers 61, which are fixed to the end of the frame 50 by screws 62 and nuts 63. The screws 62 are fixed to the end of the frame 50, then pass through the holes 611 of the washers 61, and are tightened by nuts 63. By changing the number of the plurality of washers 61, the height of the frame 50 is adjusted. For example, when the frame 50 is too close to the original document table 10, that is, the opposing plate 40 is too close to the original document table 10, several washers 61 can be removed at this time to increase the height of the frame 50, thereby increasing the distance between the opposing plate 40 and the original document table 10; when the frame 50 is too far from the original document table 10, that is, the opposing plate 40 is too far from the original document table 10, several washers 61 can be added at this time to reduce the height of the frame 50, thereby reducing the distance between the opposing plate 40 and the original document table 10. By adjusting the height of the frame 50, the distance between the opposing plate 40 and the original document table 10 is maintained within a suitable range. For example, maintaining it at 1.3 mm can avoid the contact between the leading end of the original document and the opposing plate.

[0044] In other embodiments, the height adjustment assembly 60 may include a plurality of thin films which are pre-embedded in the adjustment plates at both ends of the opposing plate. The number of the plurality of thin films is increased or decreased according to the height of the frame 50 (the gap between the frame 50 and the original document table 10), so as to keep the distance between the opposing plate 40 and the original document table 10 within a proper range. For example, keeping it at 1.3 mm can prevent the leading end of the original document from contacting the opposing plate.

[0045] Figure 7 The schematic diagram of an image forming apparatus 200 according to an embodiment of the present invention is shown. The image forming apparatus 200 may be a multi-functional machine, including a paper feeding device 210, an image reading device 100, an operation display unit 220, an image forming mechanism 230, a conveying device 240, etc. The conveying device 240 conveys the paper from the paper feeding device 210 to the image forming mechanism 230, and forms the image on the original document read by the image reading device 100 on the paper.

[0046] According to an embodiment of the present invention, the opposing plate is provided with a paper limiting portion which is located between the original document table and the opposing plate and is used for limiting the distance between the original document and the opposing plate. Through the paper limiting portion, it is possible to prevent the original document from contacting the opposing plate, ensure that the leading end of the original document can form a shadow on the opposing plate, thereby accurately judging the inclination amount of each original document, and then performing inclination correction, improving the electronic inclination correction ability.

[0047] Furthermore, the ratio of the width of the paper limiting portion to the width of the opposing plate is less than 50%. Further, within a predetermined distance on both sides of the center line of the opposing plate parallel to the paper conveying direction, the ratio of the width of the paper limiting portion to the width of the opposing plate does not exceed 50%. By limiting the width of the paper limiting portion, it is possible to accurately determine the inclination amount of the leading end of the original document, and then perform inclination correction, improving the electronic inclination correction ability.

[0048] The technical content and technical features of the present invention have been disclosed above. However, it can be understood that under the creative concept of the present invention, those skilled in the art can make various changes and improvements to the above disclosed concept, but all belong to the protection scope of the present invention. The description of the above embodiments is illustrative rather than restrictive, and the protection scope of the present invention is determined by the claims.

Claims

1. An image reading device, characterized in that: include: The manuscript table is used to place the manuscript; A reading unit, comprising a light source and a reading unit, wherein the light source is used to illuminate the manuscript, and the reading unit is used to read an image on the manuscript at a reading position; A conveying unit, used for conveying the original document to the reading unit; as well as The facing plate is located at a side of the manuscript opposite to the manuscript table at the reading position, wherein the facing plate is provided with a paper limiting portion, the paper limiting portion is located between the manuscript table and the facing plate, and is used to limit the distance between the manuscript and the facing plate.

2. The image reading device according to claim 1, characterized in that: The surface of the facing plate facing the document table is white.

3. The image reading device according to claim 2, characterized in that: The ratio of the width of the paper limiting portion to the width of the facing plate is less than 50%, and within a predetermined distance on both sides of the center line of the facing plate parallel to the paper conveying direction, the ratio of the width of the paper limiting portion to the width of the facing plate does not exceed 50%.

4. The image reading device according to any one of claims 1 to 3, characterized in that: The paper restricting portion is a plurality of convex ribs formed on the facing plate, and surfaces of the plurality of convex ribs facing the document table are white.

5. The image reading device according to claim 4, characterized in that: The plurality of convex ribs are distributed in a region 5 mm to 30 mm away from a center line on both sides of the facing plate along a center line parallel to the paper conveying direction.

6. The image reading device according to claim 4, characterized in that: The height of the plurality of convex ribs is 0.1-0.5 mm, and the width is 1-5 mm.

7. The image reading device according to any one of claims 1 to 3, characterized in that: The facing plate is further provided with a frame, a surface of the frame facing the manuscript table is located between the manuscript table and the facing plate, and the paper restricting portion is a plurality of white films mounted on the surface of the frame facing the manuscript table.

8. The image reading device according to any one of claims 1 to 3, characterized in that: The conveying unit includes an upper rail portion and a contact film connected to the upper rail portion. The contact film contacts the document table so that the document is conveyed between the contact film and the document table.

9. The image reading device according to any one of claims 1 to 3, characterized in that: The conveying unit includes an upper rail portion and a rotatable rail connected to the upper rail portion, and the rotatable rail contacts the document table, so that the document is conveyed between the rotatable rail and the document table.

10. The image reading device according to claim 7, characterized in that: The facing plate is also provided with a height adjustment component for adjusting the height of the frame.

11. The image reading device according to claim 10, characterized in that: The frame includes a plurality of frame parts, and two adjacent frame parts are connected by a connecting piece.

12. The image reading device according to claim 10, characterized in that: The height adjustment assembly includes a plurality of adjustment components, and the height of the frame is adjusted by changing the number of the plurality of adjustment components.

13. An image forming device, characterized in that: include: The image reading device according to any one of claims 1 to 12, used for reading an image on a manuscript; as well as The image forming mechanism is used to form the image read by the image reading device on a paper.

Images