Document reading device and image forming apparatus equipped with same

Abstract

To obtain a read image that has sufficiently prevented the occurrence of interference fringes during reading of a document even if the document is a photograph document or a document having glossiness.SOLUTION: A document reading device comprises: a document placement platen that has a transparent document placement unit on which a document is placed and a document reading unit that reads the document placed on the document placement unit; and a document cover that is rotatably supported on the document placement platen centered on a rotation spindle between a closing position for covering the document placement unit and an opening position for opening the document placement unit. The document cover has an elastic member that is arranged at a position corresponding to the document placement unit and has a predetermined thickness, and projections that are arranged at positions different from the arrangement position of the elastic member and project toward the document placement platen. The projections are brought into contact with the document placement platen when the document cover is at the closing position, and thereby the elastic member is arranged on the document placement unit in a state in which a side of the elastic member having the arrangement positions of the projections is moved in a direction in which the side floats from the document placement unit.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to an improvement in an original reading device provided in an image forming apparatus such as a copying machine or a multifunction machine. [Background technology]

[0002] Conventionally, document reading devices such as image scanners are generally provided with a document placement table and a document cover disposed above the document placement table. The document placement table is provided with a transparent glass plate (document placement section) on which a document is placed, and a document reading section that reads the document placed on the transparent glass plate. Meanwhile, the document cover is, for example, rotatably supported at its rear end on the document placement table, and is provided so that it can be positioned in two positions, a closed position in which the transparent glass plate is covered and an open position in which the transparent glass plate is opened, by rotating the rear end about a rotational support shaft.

[0003] In this type of document reading device, the document cover is provided with an elastic member having a size corresponding to the transparent glass plate and a predetermined thickness, and by positioning the document cover in the closed position with the document placed on the transparent glass plate and bringing the elastic member into uniform contact with the transparent glass plate, the document reading unit is configured to be able to read an image of good quality from the document.

[0004] However, when the conventional document reading device reads images of documents, particularly photographic documents or documents with a glossy surface, stain-like unevenness, known as interference fringes (Newton rings) caused by light reflected from the document, may occur in the read image data.

[0005] Therefore, in the past, for example in Patent Document 1, a ground glass portion, which is contact glass processed to a ground glass shape, has been provided in the reading portion of the document, and a document pressing means is provided to press the document against the ground glass portion. In this configuration, when reading the document, the light irradiated from the document reading portion is scattered by the ground glass portion, suppressing the occurrence of interference fringes due to the light reflected from the document, while the document is pressed reliably against the ground glass portion (contact glass) by the document pressing means, so that the image of the document is read accurately. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2008-48019 A Summary of the Invention [Problem to be solved by the invention]

[0007] The technology described in Patent Document 1 scatters the light irradiated from the document reading section by the ground glass section, thereby suppressing the occurrence of interference fringes caused by the light reflected from the document.

[0008] The inventors of the present application have discovered that in the case of photographic originals or originals having a glossy finish, when an image is read, the elastic member of the original cover presses the back side of the original against the transparent glass plate with uniform pressure, causing the entire front surface of the original to adhere closely to the transparent glass plate, making it easy for interference fringes to occur in the read image.

[0009] From this perspective, the present invention aims to effectively suppress the occurrence of interference fringes in an original reading device by adopting a configuration in which, unlike the configuration of Patent Document 1, which scatters the light irradiated from the original reading section, in the case of photographic originals or glossy originals, the entire surface of the photographic original or the like is not adhered to a transparent glass plate (image mounting section) using an elastic member. [Means for solving the problem]

[0010] Specifically, the document reading device according to the present invention includes a document placement table having a transparent document placement section on which a document is placed and a document reading section that reads the document placed on the document placement section, and a cover that covers the document placement section and rotates around a pivot shaft. closed Position and release Open and a document cover supported on the document placement table so as to be rotatable between a closed position and a closed position, the document cover having an elastic member having a predetermined thickness and disposed at a position corresponding to the document placement section, and a protruding portion disposed at a position different from the position of the elastic member and protruding toward the document placement table, the elastic member being disposed on the document placement section in a state in which the protruding portion side of the elastic member moves in a direction rising up from the document placement section when the document cover is in the closed position and the protruding portion abuts against the document placement table. The protruding portion is supported by the document cover so as to be movable toward the document placement table by a moving mechanism, and the moving mechanism moves the protruding portion between a first position where the protruding portion does not come into contact with the document placement table and a second position where the protruding portion comes into contact with the document placement table. It is characterized by the above. Effect of the Invention

[0011] According to the present invention, a protrusion is arranged on the document cover, and this protrusion protrudes toward the document placing table. When the document cover is in the closed position, the elastic member is arranged on the document placing section in a state in which the arrangement position side of the protrusion moves in a direction in which it floats up from the document placing section. As a result, when reading a document such as a photographic document, the entire surface of the photographic document is restricted from coming into close contact with the document placing section, effectively suppressing the occurrence of interference fringes in the read image. [Brief description of the drawings]

[0012] [Figure 1] 1 is a perspective view showing an image processing apparatus including an image forming apparatus equipped with a document reading device according to a first embodiment and an information terminal. [Diagram 2] 2 is an exploded perspective view showing a main part of the document reading device with the document cover positioned at the open position; FIG. [Diagram 3] 2 is an exploded perspective view showing the main parts of the document reading device with a document cover removed upward from a document placement table. FIG. [Figure 4] FIG. 2 is a top view showing a state in which the document cover is removed from the document placing platen. [Diagram 5] FIG. 2 is a side cross-sectional view showing an internal configuration of the document reading device. [Figure 6] 4 is an enlarged cross-sectional view of the internal configuration of the document reading device, showing a state in which a protruding portion is in a separated position; FIG. [Figure 7] 4 is an enlarged cross-sectional view of the internal configuration of the document reading device, showing a state in which a protruding portion is in a contact position; FIG. [Figure 8] 10 is a schematic explanatory diagram showing a state of a gap formed between the elastic member and the contact glass. FIG. [Figure 9] FIG. 2 is a block diagram showing a main part of a control system of the image processing apparatus. [Figure 10] 13 is a diagram showing the display contents of a display screen of a second operation unit provided in the terminal device. FIG. [Figure 11] 13 is a diagram showing an operation menu that is displayed on the display screen when a "Various copies" operation button on the display screen is touched. FIG. [Figure 12] 13 is a diagram showing a document size selection screen that is displayed on the display screen when a "copy photo" operation button on the display screen is touched; FIG. [Figure 13] 13 is a diagram showing an example of a scanned image and image adjustment buttons displayed on the display screen as a confirmation screen. FIG. [Figure 14] 11 is a perspective view of the essential parts, showing how a protruding portion is attached to the document cover of the document reading device of the second embodiment. FIG. [Figure 15] 4 is a side cross-sectional view showing an internal configuration of a main part of the document cover. FIG. [Figure 16] 4 is a perspective view showing the shape of a protrusion provided on the document cover. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0014] (Embodiment 1) FIG. 1 is a perspective view showing an image processing apparatus including a document reading device according to a first embodiment of the present invention.

[0015] In the figure, the image processing device 1 is a multifunction peripheral (MFP) having a copying function, a facsimile function, a printer function, etc., and has two housings, and is composed of an image forming device 2 and an information terminal 3 arranged side by side. The image forming device 2 has a document reading device 5 that reads an image of a document, and an image forming device main body 6 that records and forms the image of the document read by the document reading device 5 or an image received from the outside on a recording paper in color or monochrome. The document reading device 5 is attached to the upper surface of the image forming device main body 6. The image forming device main body 6 has a printing unit 7 that prints the image of the document read by the document reading device 5 on recording paper or glossy paper, and multiple paper feed cassettes 8, etc., and the recording paper printed by the printing unit 7 is discharged to a paper discharge tray 9 provided in the middle of the housing. The document reading device 5 also has a document placement table 13 and a document cover 15 located above it.

[0016] Meanwhile, the information terminal 3 prints the image read from the recording medium on recording paper or glossy paper, and discharges the recording paper or glossy paper to the paper discharge port 3a provided at the bottom of the housing. The image forming device 2 and the information terminal 3 are connected to each other and perform data communication, and the image forming device 2 and the information terminal 3 operate in cooperation with each other. This cooperation operation is, for example, an operation in which manuscript data of a photographic manuscript read by the manuscript reading device 5 is sent to the information terminal 3, and the manuscript data is printed by the information terminal 3 on glossy paper, photographic paper, or the like, and discharged as a photograph to the paper discharge port 3a.

[0017] In the document reading device 5, a first operation unit 11 consisting of, for example, a touch panel is disposed on the front end side of the image placement table 13, and a similar second operation unit 18 is disposed on the front end side of the upper part of the information terminal 3. These two operation units 11, 18 are operation input units that accept operation inputs from a user or the like (operator), and also have display screens 11a, 18a that display images.

[0018] <Document reader> 2 to 5 show the document reading device 5, in which Fig. 2 is a perspective view showing the main parts with the document cover 15 positioned in the open position, Fig. 3 is an exploded perspective view showing the main parts with the document cover 15 removed upward from the document placing table 13, Fig. 4 is a top view showing the document placing table 13 with the document cover 15 removed, and Fig. 5 is a side sectional view showing the internal configuration of the document reading device 5 and a sectional view taken along line VV in Fig. 4. Hereinafter, in these figures, when describing each member, the rear side of the page is referred to as the rear side, the front side of the page as the front side, the left side of the page as the left side, and the right side of the page as the right side, when an operator standing in front of the image processing device 1 looks at the image processing device 1.

[0019] The document reading device 5 is an optical type document reading device, and is configured to fix a document G (for example, a normal document printed on ordinary paper, a photographic document, or a glossy document) using a document fixation method and read the image of this document G.

[0020] The document reading device 5 includes a document placement table 13 as a reading device main body, and a document cover 15 disposed above the document placement table 13. The document placement table 13 includes a document placement section 20 on which documents G of various sizes are placed, and a document reading section 22 (see FIG. 5) that reads the documents placed on the document placement section 20. The document placement section 20 is configured with a contact glass that is a transparent thin flat plate such as a glass plate. Hereinafter, this document placement section 20 is referred to as the contact glass 20. The contact glass 20 is formed in a rectangular shape in a plan view and is disposed at the upper end of the document placement table 13. On the upper surface of this contact glass 20, rectangular resin covers 24 and 25 are disposed on the left side and rear side in the figure, respectively. On the upper surface of the contact glass 20, documents G of A3, B4, A4, B5 size, L size used for photographs, and 2L size (documents G shown in FIG. 2 and FIG. 4) can be placed. In this case, the rear left corner of the area on the top surface of the contact glass 20 where the resin covers 24, 25 are not located (hereinafter referred to as the transparent area), i.e., the upper left corner as seen by the operator, is set as the placement reference position P, and the upper left corner of the original G is aligned with this placement reference position P and the original G is placed with its surface facing downward.

[0021] The document reading unit 22 is disposed inside the document placing table 13, and although not shown in detail, it includes, for example, a light source unit that irradiates light toward the document G, an optical system drive unit that moves it in the sub-scanning direction (perpendicular to the paper surface in Figure 5), a focusing lens, and a photoelectric conversion element that repeatedly scans the light (document image light) from the focusing lens in the main scanning direction (left and right direction in Figure 5) to read the document image.

[0022] On the other hand, the document cover 15 is for pressing the back surface of the document G placed on the upper surface of the contact glass 20 from above, and is formed in a rectangular shape in a plan view. Two opening and closing hinges 28 are attached to the rear end of the document cover 15. These opening and closing hinges 28 are provided at the left end of the document cover 15 and at a position slightly closer to the center in the left-right direction than the right end. A square prism-shaped main body insertion part 29 is connected to the lower end of each opening and closing hinge 28. On the other hand, the document placement table 13 is formed with a mounting part 31 made of a square prism-shaped recess arranged at a distance equal to the mutual distance between the two main body insertion parts 29 at a position rearward of the contact glass 20. Each of the main body insertion parts 29 is inserted into the corresponding mounting part 31 from above so as to be removable, and the document cover 15 is supported on the document placement table 13 by these main body insertion parts 29.

[0023] Therefore, the document cover 15 rotates around the hinge shaft 28a of each opening / closing hinge 28 as a rotational support shaft f toward the contact glass 20, and is positioned at a closed position where it covers the contact glass 20, and at an open position where it rotates upward from the closed position to open the contact glass 20. When the document cover 15 is positioned at the closed position with a thick document G such as a book placed on the contact glass 20, the upper end of the main body insertion portion 29 protrudes slightly upward from the attachment portion 31 of the document placement table 13, and the document cover 15 is placed in a horizontal position, allowing the document G such as a book to be well covered.

[0024] An elastic member 35 is disposed on the lower surface of the document cover 15. The elastic member 35 is formed in a rectangular shape having the same area as the transparent area of ​​the contact glass 20, and is disposed above the transparent area of ​​the contact glass 20 at a position corresponding to the contact glass 20. That is, when the document cover 15 is positioned at the closed position, the positions of the four corners of the elastic member 35 coincide with the corresponding corners of the transparent area of ​​the contact glass 20, and the elastic member 35 faces the upper surface of the contact glass 20 with good precision. The elastic member 35 is formed of an elastic body having a predetermined thickness, and a thin white sheet (not shown) is attached to the lower surface of the elastic member 35. Since the lower surface of the document cover 15 has an attachment area 35a for the opening / closing hinge 28 at its rear end, the elastic member 35 is positioned forward of the attachment area 35a. When the document cover 15 is positioned at the closed position, the elastic member 35 has the function of uniformly pressing the document G on the upper surface of the contact glass 20 downward by its elastic force.

[0025] As shown in Fig. 5, the rear (upper) side of the elastic member 35 is fixed to the main body frame 16 of the document cover 15. The main body frame 16 is provided with a front frame body 16a and a rear frame body 16b that are divided into two at approximately the center in the front-rear direction. The front frame body 16a and the rear frame body 16b are connected by a folding hinge 17, and when the document cover 15 is in the open position, the front frame body 16a and the front portion of the elastic member 35 located thereunder rotate counterclockwise in Fig. 5 around the hinge shaft 17a of the folding hinge 17, so that the document cover 15 can be folded in the center.

[0026] On the lower surface of the document cover 15, two protrusions 40L and 40R are disposed protruding toward the document placement table 13. These protrusions 40L and 40R are disposed at a position different from the elastic member 35, specifically, behind the elastic member 35, that is, on the side of the rotation support shaft f (the hinge shaft 28a of the opening / closing hinge 28) of the document cover 15. When the document cover 15 is positioned at the closed position, these protrusions 40L and 40R are positioned on the document placement table 13 at the positions indicated by the broken double circles in FIG. 4. More specifically, the left protrusion 40L is disposed at the rear end of the resin cover 25 extending in the front-rear direction in FIG. 4, that is, in the vicinity of the placement reference position P of the document G on the contact glass 20. On the other hand, the right protrusion 40R is disposed at a position approximately at the center in the left-right direction of the resin cover 24 extending in the left-right direction. The position of this right-side protrusion 40R is, for example, as shown in the same figure, a position where the distance from the reference position P of the document G is a length slightly longer than the long side (178 mm) of a 2L size (127 x 178 mm) photo document G when it is placed horizontally (with the long side running left to right) (for example, 210 mm, which is half the long side of an A3 size (297 x 420 mm)).

[0027] The configurations around the two protruding parts 40L and 40R are the same. The configuration around the right protruding part 40R will be described below. FIG. 6 is an enlarged view of the right protruding part 40R and its surroundings in the side cross-sectional view of the document reading device 5 shown in FIG. 5. In FIGS. 5 and 6, the protruding part 40R is composed of a disk-shaped horizontal plate 42 and a shaft part 43 located at the center of the horizontal plate 42 and extending in the vertical direction. The shaft part 43 faces a notch part 19 that is formed by cutting the main body frame 16 of the document cover 15 downward (on the document placement table 13 side) in a convex shape, and the horizontal plate 42 is located below the notch part 19 and faces the upper surface of the resin cover 24 of the document placement table 13. The two protruding parts 40L and 40R can each be moved toward the contact glass 20 by a moving mechanism 47.

[0028] As shown in detail in an enlarged view in FIG. 6, the moving mechanism 47 includes an eccentric cam 48, a spring 49, and a retaining plate 50. The retaining plate 50 is fixed to the upper end of the shaft 43 of the protruding portion 40R. The spring 49 is compressed between the retaining plate 50 and the periphery of the notch 19, and the shaft 43 of the horizontal plate 42 is inserted into the spring 49. The spring 49 moves the protruding portion 40R upward by its urging force, and the horizontal plate 42 is positioned around the notch 19. The eccentric cam 48 is disposed above the rear frame 16b of the main body frame 16 of the document cover 15, and abuts against the upper surface of the shaft 43 of the horizontal plate 42 via the retaining plate 50. As shown in FIG. 7, the eccentric cam 48 rotates around its cam shaft 48a, thereby moving the protruding portion 40R downward (toward the document placement table 13). Specifically, as shown in FIG. 6, when the eccentric cam 48 abuts its short diameter portion against the upper surface of the shaft portion 43 of the horizontal plate 42, the protrusion 40R is positioned upward by the biasing force of the spring 49, and the horizontal plate 42 is separated from the plastic cover 24 of the document placing table 13 and is positioned in a separated position (first position) where it does not abut against the document placing table 13.

[0029] On the other hand, in the moving mechanism 47, as shown in Fig. 7, when the eccentric cam 48 abuts its major diameter portion against the upper surface of the shaft portion 43 of the horizontal plate 42, the protrusion 40R moves downward against the biasing force of the spring 49, and the horizontal plate 42 abuts against the resin cover 24 of the document placement table 13, and the protrusion 40R is positioned at the abutment position (second position) where the protrusion 40R abuts against the document placement table 13. At this abutment position, the elastic member 35 of the document cover 15, in the vicinity of the arrangement position of the protrusion 40R, floats upward from the contact glass 20. The details of the operation of the elastic member 35 floating up are as follows. That is, when the horizontal plate 42 of the protrusion 40R abuts against the resin cover 24 of the document placement table 13, the rear frame body 16b of the main body frame 16 of the document cover 15 floats up slightly upward. At this time, the rear frame 16b of the main body frame 16 rotates clockwise around the hinge shaft 17a of the center-folding hinge 17 as indicated by the arrow d in Fig. 7 and rises. Therefore, the main body insertion portion 29 of the opening / closing hinge 28 of the document cover 15 rises upward as indicated by the arrow e and comes out of the mounting portion 31 of the document placement table 13. As a result, the elastic member 35 of the document cover 15 is lifted upward from the contact glass 20 in the vicinity of the position where the protrusion 40R is disposed, the gap between the elastic member 35 of the document cover 15 and the contact glass 20 expands, and the document cover 15 is placed on the contact glass 20 with a gap Δt formed.

[0030] The gap Δt is set to, for example, a predetermined length Δt1 (for example, a maximum value of 1 mm or less, preferably about 0.2 to 0.3 mm). As shown in Fig. 8, this length Δt1 has the maximum value at the rear end position in the front-rear direction of the document G, i.e., at the position of the placement reference position P of the document G, and gradually narrows toward the front, and it is preferable that the length Δt1 is equal to or less than the thickness of the photo document G at a position slightly longer than the short side (127 mm) of a 2L size (127 x 178 mm) photo document G placed horizontally.

[0031] Furthermore, when the manuscript cover 15 is in the closed position, the protrusion 40R is positioned at the abutment position, thereby forming a gap Δt between the elastic member 35 and the contact glass 20 near the position of the protrusion 40R. However, this gap Δt does not necessarily have to be formed, and it may be in a state in which the gap between the elastic member 35 and the contact glass 20 expands microscopically and moves in a direction in which it floats up from the contact glass 20, for example, a state in which the elastic member 35 is not in close contact with the contact glass 20 due to its elastic force, but is simply in contact with the upper surface of the contact glass 20 (in other words, a state in which no elastic force is acting on the contact glass 20).

[0032] The length Δt1 of the gap Δt can be finely adjusted by minutely rotating the eccentric cam 48 using the control unit 60, which will be described later. This configuration will be described below.

[0033] Fig. 9 is a block diagram showing an outline of the main parts of the control system of the image processing device 1. In the figure, the control system of the image processing device 1 is provided with a control unit 60. Operation signals are input to the control unit 60 from a first operation unit 11 and a second operation unit 18 that accept instructions for the document reading operation of the document reading unit 22 from an operator of the image processing device 1. The control unit 60 controls the document reading operation of the document reading unit 22 based on the operation signals from these operation units 11 and 18, and also controls a motor 63 that rotates the eccentric cam 48 of the movement mechanism 47 provided in the document cover 15. A specific description will be given below.

[0034] FIG. 10 shows a specific example of the display screen 18a of the second operation unit 18. In the figure, the second operation unit 18 has various operation buttons 65 on the display screen 18a, such as "one-sided copy," "print / scan with smartphone," "various copies," "network print," "photo / document print," "fax," "scan," and "government services." For example, when the "various copies" operation button 65 is touched, the display screen 18a is switched to display a document type selection screen (document type selection section) 67 in which the operator selects the type of document, as shown in FIG. 11. In this document type selection screen 67, various operation buttons 66, such as "copy on one side," "copy on both sides," "enlarge / reduce," "copy on postcard," and "copy photo," are displayed as various copy menus. The "copy photo" operation button 66 is operated when copying a glossy document G on which various printing has been applied to glossy paper (hereinafter referred to as a glossy document) in addition to a photo document G. Hereinafter, when referring to a photo document G, the glossy document G is included.

[0035] When the operation button 66 for "copying photo" is touched, the display screen 18a is switched to display two types of buttons 68 for specifying the size of the photo original G, one for specifying L size and one for specifying 2L size, as shown in FIG. 12. The control unit 60 receives an operation signal specifying the L size or 2L size, and drives the motor 63 for rotating the eccentric cam 48 so as to position the protruding parts 40L and 40R at the contact position, and controls the document reading unit 22 to read the L size or 2L size photo original G after driving the motor 63. That is, when the L size or 2L size photo original G (including a glossy original G) is selected and specified as a predetermined specific type of original, the control unit 60 controls the rotational operation of the eccentric cam 48 of the moving mechanism 47 by the motor 63 so as to position the protruding parts 40L and 40R at the contact position.

[0036] On the other hand, when any of the operation buttons 66 other than "Copy photo", i.e., "Copy on one side", "Copy on both sides", "Enlarge / reduce", and "Copy to postcard" are touched on the document type selection screen 67 in FIG. 11, this is a copy operation using regular paper or a postcard as the document G, so the control unit 60 drives the motor 63 for rotating the eccentric cam 48 so as to position the protrusions 40L and 40R in the separated position.

[0037] In this way, depending on the content of the document reading operation received by the second operating unit 18, the control unit 60 controls the rotational operation of the eccentric cam 48 of the moving mechanism 47 so as to move the protrusions 40L, 40R to the abutment position when reading an L-size or 2L-size photo document G, while controlling the rotational operation of the eccentric cam 48 of the moving mechanism 47 so as to move the protrusions 40L, 40R to the separated position when reading a document G such as a document printed on regular paper other than the photo document G.

[0038] After the document reading unit 22 reads the L-size or 2L-size photo document G, the control unit 60 displays the read image obtained by the document reading operation on the confirmation screen 69, as shown in FIG. 13, by using the display screen 18a of the second operation unit 18 as a confirmation screen 69. In the figure, the confirmation screen 69 displays a read image (mountain image) of the photo document G, and shows an example in which interference fringes m occur in the read image. The confirmation screen 69 also displays operation buttons (adjustment operation buttons) 70 for image adjustment. The operator of the image processing device 1 checks the image (confirmation image) on the confirmation screen 69, and if interference fringes m occur in the confirmation image, it is possible to touch the operation button 70 for image adjustment (for adjusting clarity) to eliminate the interference fringes m. The control unit 60 receives an operation signal from the image adjustment operation button 70, and operates the motor 63 for rotating the eccentric cam 48 in accordance with the operation signal to adjust the amount of protrusion of the protrusions 40L, 40R, thereby adjusting the length Δt1 of the gap Δt between the elastic member 35 and the contact glass 20.

[0039] Therefore, in the present embodiment, when the operator places the upper left corner of the photographic document G on the upper surface of the contact glass 20 in alignment with the placement reference position P and touches the operation button 66 for "copying a photo", the control unit 60 controls the motor 63 to rotate the eccentric cam 48 of the moving mechanism 47, causing the protruding portions 40L and 40R to protrude toward the contact glass 20 and move to the contact position. As a result, the elastic member 35 of the document cover 15 floats upward in the vicinity of the arrangement positions of the protruding portions 40L and 40R, that is, in the arrangement area of the photographic document G, and the space between the elastic member 35 and the contact glass 20 expands, and the contact glass 20 is placed in a state where a gap Δt is formed. Since the length Δt1 of this gap Δt is large at the rear end position of the contact glass 20 (the position side of the placement reference position P) and gradually decreases toward the front, the entire back surface of the photographic document G is not uniformly pressed by the elastic force of the elastic member 35, and the surface of the photographic document G is not uniformly in close contact with the contact glass 20 over its entire surface. As a result, during the document reading operation of the photographic document G by the document reading unit 22, the generation of interference fringes m caused by the entire surface of the photographic document G and the contact glass 20 being in close contact with each other under uniform pressure is effectively suppressed.

[0040] Here, the protruding portions 40L and 40R are arranged on the rear end side in the front-rear direction of the document cover 15, that is, on the side of the rotation fulcrum (hinge shaft 28a of the opening / closing hinge 28) of the document cover 15. Since there is an attachment area 35a for the opening / closing hinge 28 on the rear side of the elastic member 35 on the side of this rotation support shaft f, as shown in FIG. 6, the distance k from the rear end position E of the elastic member 35 to the rear end position C of the document cover 15 is long. On the other hand, since there is no attachment area 35a for the opening / closing hinge 28 or the like at the front end position of the elastic member 35, as shown in FIG. 5, the distance r between the front end position of the elastic member 35 and the front end position of the document cover 15 is shorter than the distance k (r < k). Therefore, even when there is a gap Δt between the elastic member 35 and the contact glass 20 in the vicinity of the positions of the protruding portions 40L and 40R when the document cover 15 is in the closed position, it is difficult for external light to reach the positions of the protruding portions 40L and 40R, so it is possible to sufficiently suppress the entry of external light into the contact glass 20 through the gap Δt, and it is possible to more reliably prevent noise from entering the read image of the photographic document G.

[0041] Moreover, when the document G placed on the contact glass 20 is a document G other than a photographic document G, for example, a document G (normal document G) printed on normal paper or the like that is unlikely to produce interference fringes m, the control unit 60 positions the protruding parts 40L and 40R at the separated position by the moving mechanism 47, and there is no gap Δt between the elastic member 35 and the contact glass 20. Therefore, the back surface of the normal document G on the upper surface of the contact glass 20 is pressed toward the contact glass 20 by the elastic force of the elastic member 35, and the entire surface of the normal document G is uniformly pressed against the contact glass 20. Therefore, even if the normal document G has a folding trace, the occurrence of floating of the normal document G is suppressed, the characters printed on the normal document G are less likely to bleed or fade, and the folding traces are sufficiently suppressed from being read as streaks.

[0042] Furthermore, when photo original G is read by document reading unit 22, the read image is displayed on confirmation screen 69, and the operator can operate operation button 70 for adjusting the image clarity if interference fringes m occur in the read image. At this time, control unit 60 controls motor 63 of movement mechanism 47 in response to operation of operation button 70 to adjust the amount of protrusion of protrusions 40L, 40R and finely adjust length Δt1 of gap Δt between elastic member 35 and contact glass 20. Therefore, even if interference fringes m occur in the read image at first when photo original G is read, it is possible to eventually obtain a good read image without interference fringes m.

[0043] (Embodiment 2) FIG. 14 is a perspective view showing a main part of an original cover 15 of an original reading device 5 according to a second embodiment of the present invention, and FIG. 15 is a side sectional view of the main part of the original reading device 5. As shown in FIG.

[0044] In the above-mentioned embodiment 1, a moving mechanism 47 is provided so that the position of the protrusions 40L, 40R can be changed between an abutment position and a separation position. In the present embodiment, however, only the protrusions 40L, 40R are arranged, and a moving mechanism 47 is not provided.

[0045] 14 and 15, two protrusions 40L, 40R (only the left protrusion 40L is shown) are disposed near the pivot shaft f on the underside of the manuscript cover 15, as in the first embodiment. The protrusions 40L, 40R are inserted into the notch 19 of the main body frame 16 of the manuscript cover 15. As shown in FIG. 16, the protrusions 40L, 40R have a horizontal plate 42 and a shaft 43, and the shaft 43 has a locking portion 44 formed by cutting out the periphery thereof, and the locking portion 44 is locked to the periphery of the notch 19 of the main body frame 16, and the protrusions 40L, 40R are attached to the main body frame 16.

[0046] The horizontal plate 42 of the protruding portions 40L and 40R protrudes from the main body frame 16 of the document cover 15 toward the contact glass 20, and when the document cover 15 is in the closed position, the horizontal plate 42 abuts against the upper surface of the resin cover 24 of the document placement table 13, and a gap Δt is formed between the elastic member 35 and the contact glass 20 in the vicinity of the positions of the protruding portions 40L and 40R. The length Δt2 of this gap Δt is set to a smaller value (Δt2<Δt1) than the length Δt1 of the gap Δt in the first embodiment. That is, since the present embodiment does not include the moving mechanism 47 in the first embodiment, the length Δt2 of the gap Δt is set to a length that does not cause interference fringes m when a photographic document G is read, and does not cause bleeding or blurring of printed characters when a normal document G is read.

[0047] Therefore, in this embodiment, by providing only the protrusions 40L and 40R, it is possible to obtain a clean read image with suppressed occurrence of interference fringes m when reading a photographic original G while maintaining good image reading of the normal original G. Moreover, since there is no movement mechanism 47 as in the first embodiment, the configuration can be simplified.

[0048] The present invention can be implemented in various other forms without departing from its spirit or main features. Therefore, the above-described embodiments are merely illustrative and should not be interpreted as being limited. All modifications and variations within the scope of the claims of the present invention are within the scope of the present invention.

[0049] For example, in the first and second embodiments, two protrusions 40L, 40R are provided, but the number is not limited to 2. Also, the range of the gap Δt formed between the elastic member 35 and the contact glass 20 by the protrusions 40L, 40R is exemplified as being slightly wider than the entire surface of the 2L-size photographic original G, but is not limited to this range.

[0050] Furthermore, although the two protrusions 40L, 40R are disposed on the pivot shaft f side of the document cover 15, multiple protrusions (e.g., two) may be disposed in the front-rear direction of the document cover 15. For example, the protrusions 40L, 40R may be disposed on the document cover 15 so as to be positioned on the left end of the contact glass 20, i.e., on the resin cover 25 extending in the front-rear direction, when the document cover 15 is in the closed position.

[0051] Furthermore, although the moving mechanism 47 in the first embodiment is exemplified as having an eccentric cam 48, other mechanisms such as a mechanism having a mountain-shaped linear cam that moves linearly to move the protrusions 40L and 40R, or a mechanism using an electromagnetic solenoid to move the protrusions 40L and 40R by electromagnetic force may be adopted. Also, a mechanism for manually moving the eccentric cam 48 may be adopted. When this manual moving mechanism is adopted, the fact that the position of the document cover 15 has been changed may be displayed or notified on the display screen 18a of the second operation unit 18, for example. In addition, although the document cover 15 is configured to have the hinge 17 for folding, it may be a normal flat document cover without a folding function.

[0052] In addition, in embodiment 1, the display screen 18a of the second operation unit 18 was used to instruct the image reading operation of the document G and to display the read image, but these instructions and displays may also be performed using the display screen 11a of the first operation unit 11. [Industrial Applicability]

[0053] The present invention is useful when applied to an original reading device because it can obtain a read image in which the occurrence of interference fringes is sufficiently suppressed when reading an original, even if the original is a photograph or a glossy original. [Explanation of symbols]

[0054] 1 Image processing device 2. Image forming device 5 Document reader 13 Document stand 15 Manuscript Cover 18 2nd operation section 18a display screen G Manuscript 20 Contact glass (original placement area) 22 Document reading section 28 Opening and closing hinge f Rotation shaft 35 Elastic member 40L, 40R protrusion 47 Moving mechanism 48 Eccentric Cam Δt1 Gap length 60 Control section 63 Motor 67 Document type selection screen (Document type selection section) 69 Confirmation Screen 70 Image adjustment operation buttons (adjustment operation buttons) m Interference fringes

Claims

1. a document placement table having a transparent document placement section on which a document is placed and a document reading section that reads the document placed on the document placement section; a document cover supported on the document placement platform so as to be rotatable about a pivot shaft between a closed position for covering the document placement section and an open position for opening the document placement section, The manuscript cover is an elastic member having a predetermined thickness and disposed at a position corresponding to the document placement portion; a protruding portion that is disposed at a position different from a position where the elastic member is disposed and that protrudes toward the document placement table, When the document cover is in the closed position, the protruding portion comes into contact with the document placement table, so that the elastic member is disposed on the document placement section in a state in which the arrangement position side of the protruding portion of the elastic member moves in a direction in which the protruding portion rises up from the document placement section, the protruding portion is supported by the document cover so as to be movable toward the document placement table by a moving mechanism; The moving mechanism includes: The protruding portion is moved to a first position where it does not come into contact with the document placement table and a second position where it comes into contact with the document placement table.

2. A document reading apparatus comprising:

2. The protrusion of the elastic member contacts the document placement table, so that a gap is formed between the document placement portion and the elastic member.

2. The document reading device according to claim 1, wherein the document reading device is a document reading device.

3. The protruding portion is disposed on the side of the rotation shaft of the document cover.

3. The document reading device according to claim 1, wherein the document reading device is a document reading device.

4. A control unit that controls the movement mechanism; an operation unit that receives an instruction for a document reading operation of the document reading unit from an operator, The control unit is controlling the moving mechanism to move the protrusion in accordance with the content of the document reading operation received by the operation unit; 4. The document reading device according to claim 1, wherein the document reading device is a document reading device having a first scanning direction.

5. the operation unit has a document type selection unit for allowing an operator to select a document type; The control unit is When a specific type of document is selected by the document type selection unit, the moving mechanism is controlled to move the protrusion to the second position.

5. The document reading apparatus according to claim 4,

6. The predetermined specific type of document is a photograph document or a glossy document.

6. The document reading device according to claim 5,

7. the operation unit has a confirmation screen for displaying a read image obtained by a document reading operation of the document reading unit, and an adjustment operation button for adjusting the read image displayed on the confirmation screen; The control unit is The moving mechanism is controlled so as to adjust the gap between the elastic member and the document placement section in response to an operation of the adjustment operation button when the read image is displayed on the confirmation screen.

7. The document reading device according to claim 4, wherein the document reading device is a document reading device having a first surface and a second surface.

8. The document reading device according to any one of claims 1 to 7 is provided.

1. An image forming apparatus comprising:

Images