Image reading device

Abstract

To achieve a buffer structure in an opening and closing operation of a document holding unit with a simple configuration.SOLUTION: An image reading device comprises: a housing 60 that has, on its top face, a document placement table 11 on which a document is placed; image reading means 41 for reading the document placed on the document placement table 11; a document holding unit 20 that can be opened and closed between a pressing position for pressing the document placed on the document placement table 11 and an opening position for opening the document placement table 11; and a hinge unit 30 that rotatably connects the document holding unit 20 with the housing 60. The hinge unit 30 has a rotation shaft 37 that is rotated in association with the opening and closing of the document holding unit 20, and a rotary dumper 34 that is attached to the rotation shaft 37.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to an image reading device for reading an image of a document composed of a sheet material such as paper or a booklet.

Background Art

[0002] As this type of image reading device, for example, the one described in Patent Document 1 is known. The image reading device described in Patent Document 1 includes a document reading device main body for placing a document and reading an image of the document, and a document pressing plate provided on the document reading device main body for pressing the document.

[0003] In the document reading device of Patent Document 1, the document pressing plate is swingably supported on the document reading device main body via a hinge. The hinge is provided with a cam portion and a spring that exerts an elastic force to press it, and the cam shape and the elastic force of the spring exert a buffering effect in the opening and closing operation of the document pressing plate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the technique described in Patent Document 1, detailed adjustment may be required between the shape of the cam and the elastic force of the spring, or the structure may become complicated.

Means for Solving the Problems

[0006] The image reading device according to the present invention, in view of the above, a housing having a document placement table on which a document is placed on an upper surface, image reading means for reading a document placed on the document placement table, A document holder that can be opened and closed between a pressing position for pressing the document placed on the document tray and an opening position for opening the document tray, A hinge that rotatably connects the document holder to the housing and Equipped with, The aforementioned hinge is, A rotating shaft that rotates in conjunction with the opening and closing of the document holder, A rotary damper attached to the aforementioned rotating shaft and a rotating part positioned at a different location on the same axis, A contact portion that contacts the rotating portion in conjunction with the opening and closing of the document holder portion and rotates the rotating portion 、 It has a connecting part fixed to the document holder part, The contact portions are attached to the connecting portion in pairs at multiple positions on the rotation axis of the hinge. One of the pair of abutting parts is fixed to the connecting part, The other of the pair of contact portions is mounted so as to be rotatable by a predetermined angle relative to the connecting portion. It is characterized by the following: [Effects of the Invention]

[0007] According to the present invention, a cushioning structure for the opening and closing operation of the document holder can be realized with a simple configuration. [Brief explanation of the drawing]

[0008] [Figure 1] A schematic diagram of an image reading device according to one embodiment of the present invention. [Figure 2] A top view of an image reading device according to one embodiment of the present invention. [Figure 3] Another top view of an image reading device according to one embodiment of the present invention. [Figure 4] Block diagram of the control unit of the image reading device. [Figure 5] Another side view of an image reading device according to one embodiment of the present invention. [Figure 6] Another rear view of an image reading device according to one embodiment of the present invention. [Figure 7] Another top view and schematic cross-sectional view of an image reading device according to one embodiment of the present invention. [Figure 8] A schematic diagram of an image reading device according to one embodiment of the present invention. [Figure 9] Schematic diagram of an image reading apparatus according to an embodiment of the present invention. [Figure 10] Cross-sectional view of the hinge 30 according to an embodiment of the present invention. [Figure 11] Cross-sectional view of another aspect of the hinge 30 according to an embodiment of the present invention. [Figure 12] Another schematic cross-sectional view and detailed view of the main part of the image reading apparatus according to an embodiment of the present invention. [Figure 13] Another schematic cross-sectional view and detailed view of the main part of the image reading apparatus according to an embodiment of the present invention. [Figure 14] Schematic cross-sectional view of the image reading apparatus according to an embodiment of the present invention. [Figure 15] Schematic diagram of an image reading apparatus according to another embodiment of the present invention. [Figure 16] Cross-sectional view of the hinge 301 according to another embodiment of the present invention.

Mode for Carrying Out the Invention

[0009] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings.

[0010] FIG. 1 is a perspective view of an embodiment of a flatbed scanner as an example of the image reading apparatus of the present invention.

[0011] As shown in FIG. 1, the flatbed scanner 1 of the present embodiment places the document D on the glass document placement table 11 provided on the upper part of the lower housing 60, covers the document D with the document pressing part 20, and scans the carriage 40 (including an image reading sensor 41 such as a CCD [Charge Coupled Device] or a CIS (Contact Image Sensor), which is an example of the image reading means) provided in the lower housing 60 of the flatbed scanner 1 in the arrow y direction to read the image of the document D.

[0012] In this embodiment, a document holder 20 that can be opened and closed relative to the lower housing 60 of the flatbed scanner 1 is attached to the end of the lower housing 60 so as to be rotatable about an axis parallel to the longitudinal direction in the xy plane of the lower housing 60.

[0013] The document holder 20 is a member that covers the document placement table 11 and the document D placed on the document placement table 11.

[0014] In this embodiment of the flatbed scanner 1, the lower housing 60, document holder 20, hinge 30 (see Figure 8), upper cover 12 (see Figure 3), carriage 40 (see Figure 7), carriage lock member 65 (see Figure 5), and shafts 42a and 42b (see Figure 7) are made of metal. This allows for a shorter grounding path to prevent static electricity from discharging and damaging the substrate along the path. Although metal parts not connected to ground can become noise sources, the presence of surrounding metal parts connected to ground allows for grounding with the minimum necessary components. In this embodiment, iron is used as the metal, but it is not limited to iron; stainless steel, aluminum, copper, etc., may also be used.

[0015] Figure 2 is a top view of the flatbed scanner 1 according to this embodiment. The flatbed scanner 1 has an operating section 50 adjacent to the document holder 20 at the end of the document holder 20 opposite to the hinge 30 during rotation (the radial tip side during rotation).

[0016] The operation unit 50 consists of a scan start button 51, a scan stop button 52, and a power button 53. When the scan start button 51 is pressed, the carriage 40 moves in the sub-scanning direction (y-direction) while the image reading sensor 41 scans in the main scanning direction, thereby starting the reading of the document D on the document tray 11. Regarding the start of scanning, the application running on the information processing device connected to the flatbed scanner 1 may send scan settings and a scan start instruction simultaneously, or a combination of these. That is, when the application on the information processing device detects that the scan start button 51 has been pressed on the flatbed scanner 1, the information processing device may send scan settings and a scan start instruction to the flatbed scanner 1 again, and then perform the scan. Furthermore, the information processing device connected to the flatbed scanner 1 may be located in a remote location via a network, and the connection method is not limited to wired connections; it may also be done wirelessly.

[0017] Figure 3 is a top view of the flatbed scanner 1 according to this embodiment. Figure 3(a) shows the flatbed scanner 1 with the upper cover 12 and document tray 11 attached, and Figure 3(b) shows the flatbed scanner 1 with the upper cover 12 and document tray 11 removed.

[0018] As shown in Figure 3(b), a control board 63 is located on the bottom surface of the flatbed scanner 1.

[0019] The control board 63 is connected to the image reading sensor 41 by a connection cable (connection means) 64. The connection cable 64 is made of a flexible flat cable (FFC) or the like. A scan start signal, based on the pressing of the scan start button 51, is transmitted to the control unit (control means) 68 (see Figure 4) mounted on the control board 63. Figure 4 shows a control block diagram of the flatbed scanner 1. When the scan start signal is transmitted from an external information processing device to the control unit 68 via the communication unit, the control unit 68 transmits a control signal to the image reading sensor 41 via the connection cable 64, which is an example of an interface unit, based on the set scan settings, and simultaneously transmits a control signal to the drive means 69 of the carriage 40, thereby executing the image reading operation of the document D. The control signal to the drive means 69 may be transmitted via the connection cable 64, but in this embodiment, since the drive means 69 is provided separately from the carriage 40, a separate cable is used. The control unit 68 performs general drive control of the image reading sensor 41 and carriage 40 in addition to scan start, and is made of a CPU or ASIC as an example.

[0020] One end of the connecting cable 64 is connected to the image reading sensor 41, and the other end is connected to a connector (not shown) provided on the control board 63.

[0021] Figure 5 is a side view of the flatbed scanner 1 according to this embodiment. A carriage lock member 65 is provided on the lower housing 60 to restrict the movement of the carriage 40 in the scanning direction (y direction). This carriage lock member 65 is slidably mounted on the lower housing 60, and by sliding the carriage lock member 65 to the fixed position, the movement of the carriage 40 is restricted. By restricting the movement of the carriage 40, for example, when moving the flatbed scanner 1, it is possible to prevent the carriage 40 from moving inside the lower housing 60 and causing unnecessary load. When the carriage lock member 65 is slid to the release position, the restriction on the movement of the carriage 40 is released.

[0022] Figure 6 is a rear view of the flatbed scanner 1 according to this embodiment. A power cable that supplies power to the power supply board is connected to the power supply board via a power cable connector 71, and power is supplied to the device. In addition, a communication cable for connecting an information processing device that transmits scanned images of the document D acquired by the flatbed scanner 1 and receives scanning settings is connected to the control board 63 via a communication cable connector 72. A USB cable or the like is used as the communication cable. In this embodiment, the control board 63 and the power supply board are configured as a common board.

[0023] Figure 7 is a top view of an image reading device according to one embodiment of the present invention. Figure 7(b) shows the AA cross section in Figure 7(a). An engagement hole member 43 provided at the lower part of the carriage 40 is inserted through an shaft 42a extending from one end to the other of the lower housing 60. The movement of the carriage 40 is performed by controlling a belt that engages with an engagement part provided on the carriage 40, which is an example of a driving means 69, using a control board 63. In this embodiment, a belt and a motor that drives the belt are used as the driving means 69, but the driving means 69 is not limited to this, and a motor and a lead screw may be used, and various modifications are possible.

[0024] The engagement hole member 43 is formed in a cylindrical shape having a predetermined length in the y direction relative to the shaft 42a. In this embodiment, the movement of the carriage 40 is supported by inserting a shaft 42b, which extends from one end to the other end of the lower housing 60, at a position opposite to the shaft 42a with respect to the center in the x direction, and a belt for driving the carriage 40 is provided at an outer position (outside in the x direction). The belt is provided on the shaft 42a side, which prevents the carriage 40 from tilting when the driving force from the belt is transmitted to the engagement hole member 43. In other words, the carriage 40 is stably supported by supporting one end of the carriage 40 with a predetermined distance from the side wall of the lower housing 60 at the center of the carriage 40 in the x direction by supporting the other end with a predetermined distance from the side wall of the lower housing 60 at the shaft 42b, while the belt provided on the shaft 42a side prevents the carriage 40 from tilting during movement when the carriage 40 is driven.

[0025] <Manuscript holding mechanism configuration> Figure 8 is a schematic diagram of an image reading device according to one embodiment of the present invention. As shown in Figure 8, the document holder 20 is rotatably attached to the lower housing 60 via a hinge 30. A pair of hinges 30 are attached to the rear end of the document holder 20, spaced apart in the y-direction. The configuration of both hinges 30 is the same.

[0026] Figure 9 is an enlarged view of the hinge 30. Figure 9(a) shows the hinge 30 with the fixing part 31 attached, and Figure 9(b) shows the hinge 30 with the fixing part 31 removed. The hinge 30 extends in the z direction and has a fixing part 31 that is inserted into and fixed to the lower housing 60, and a rotating part 33 that is movably connected to the fixing part 31 via a hinge shaft 32. This rotating part 33 is fixed to the document pressing unit body 21.

[0027] Furthermore, a rotary damper 34 is included to mitigate the impact caused by collision with the document rest 11 when the document pressing body 21 of the document holder 20 moves in the closing direction. The rotating part 33 has racks 35a and 35b through which the hinge shaft 32 passes, and engages with pinions 36a and 36b located on both sides of the rotary damper shaft 37 that passes through the rotary damper 34, so that a force acts to mitigate the impact when the document holder 20 moves in the closing direction.

[0028] Furthermore, one of the racks 35a or 35b is fixed to the rotating part 33, while the other is fixed to the axis of the hinge shaft 32 by a stepped screw or the like, allowing it to rotate by a small amount. With this configuration, even if there is a phase difference in the gears on both sides of the rotary damper 34 due to tolerances or mounting errors, one side can rotate by a predetermined angle of a small amount, so the rotational movement of the document holder 20 becomes smoother and the load can be applied evenly to the rotary damper shaft 37.

[0029] The drive from the rotating part 33 to the rotary damper 34 may be transmitted by a pair of racks 35a and pinions 36a, but in this embodiment, racks 35a and 35b and pinions 36a and 36b are arranged on both sides of the rotary damper 34. By arranging them on both sides of the rotary damper 34, the load on the rotary damper shaft 37 can be made equal on both sides when the document holder 20 rotates.

[0030] With a single drive configuration, the document holder 20 tilts to one side during rotation, placing a large load on one of the connecting parts (for example, the rack 35a and pinion 36a). By arranging them on both sides, wear on the racks 35a and 35b and the pinions 36a and 36b, as well as wear on the rotary damper shaft 37, can be suppressed.

[0031] For each of the left and right hinges 30, it is possible to appropriately change which of the racks 35a and 35b is fixed to the rotating part 33 and which is allowed to rotate by a small amount. However, aligning them to the outside or inside of the housing 60 in the y-direction makes it easier to balance the load on each component and suppress the aforementioned wear. For example, if they are aligned to the outside, one hinge will have 35a fixed and the other will have 35b fixed. However, in order to make the hinges 30 common parts for both sides, the parts to which the racks 35a or 35b are fixed may be the same.

[0032] In this embodiment, the rack 35a or 35b is configured to rotate by a small amount around the axis of the hinge shaft 32. However, a similar effect can be obtained by configuring either the pinion 36a or pinion 36b to rotate by a small amount around the axis of the rotary damper shaft 37.

[0033] In this embodiment, the torque load applied to the rotary damper 34 is configured to act only in the direction that closes the document holder 20, but a torque load may also be applied in the direction that opens the document holder 20.

[0034] Figure 10 shows a cross-sectional view of the hinge 30 in the plane (xz plane) perpendicular to the rotary damper shaft 37. In Figure 10, (a) corresponds to the open position of the document holder 20, (b) to the 45° closed position, and (c) to the pressed position (90° closed position). As shown in Figure 10, in this embodiment, the teeth of the racks 35a and 35b mesh with the pinions 36a and 36b at all positions of the opening and closing operation of the document holder 20.

[0035] In this state, when the document holder 20 is positioned between (a) and (b), the torque load applied to the rotary damper 34 by the weight of the document holder 20 is below the limit value of the rotary damper 34, so the document holder 20 stops in this position.

[0036] On the other hand, when the document holder 20 is positioned between (b) and (c), the torque load applied to the rotary damper 34 by the weight of the document holder 20 exceeds the limit value of the rotary damper 34. Therefore, the document holder 20 moves toward the pressing position (c) while being decelerated by the rotary damper 34. In this way, by appropriately setting the limit value, it is possible to adjust the angle at which the document holder 20 can be stopped.

[0037] Figure 11 also shows another configuration of pinions 36a and 36b. In Figure 11, (a) corresponds to the open position of the document holder 20, (b) to the 45° closed position, and (c) to the pressed position (90° closed position). In this configuration, the gears of the racks 35a and 35b and the pinions 36a and 36b are configured to mesh only near the pressed position and the open position of the document holder 20. With this configuration, the rotary damper 34 can be operated only near the open position and the pressed position of the document holder 20, and the document holder 20 can be opened and closed smoothly in between. However, the configuration is not limited to this, and the racks 35a and 35b and the pinions 36a and 36b may be configured to mesh only at a desired position between the open position and the pressed position of the document holder 20.

[0038] Furthermore, although the gear teeth of the rack 35 and pinion 36 are composed of multiple teeth, the drive may be transmitted to the rotary damper 34 with one tooth or an equivalent configuration. That is, the rotary damper 34 may be operated by providing a projection on the rack 35 and another projection on the pinion 36 that can contact it.

[0039] With the configuration described above, this embodiment can mitigate the impact caused by the collision between the document placement table 11 and the document holding part 20 with a simpler configuration than the conventional method which includes a slider slidably provided in a direction perpendicular to the axial direction of the hinge axis, a cam part that contacts the slider, and a mechanism that biases the slider toward the cam part.

[0040] <Configuration of the manuscript attachment area> Figure 12(a) is a cross-sectional view of BB in Figure 8, and Figure 12(b) shows an enlarged view of the frame in Figure 12(a). The document holder 20 consists of a document pressing body 21 and a document contact part 22. In Figure 12(a), the document pressing body 21 and the document contact part 22 are rotatable between a pressing position where the document is pressed and an open position where the document tray 11 is opened, with the hinge shaft 32 as the pivot point, and the document contact part 22 is rotatable relative to the document pressing body 21. The document pressing body 21 has an opening with a locking part 21a, and the document contact part 22 is provided with a locking part 22a. The locking portion 21a is movable within the opening where the locked portion 22a is provided. By engaging (contacting) the locked portion 22a provided at the end of the opening, the document contact portion 22 can rotate by a predetermined amount relative to the document pressing body 21, and the document contact portion 22 is prevented from detaching from the document pressing body 21. Figure 12(c) shows the state in which the document contact portion 22 protrudes from the document pressing body 21 on the negative side in the z direction.

[0041] Furthermore, the rotation axis of the document contact portion 22 may not be the hinge axis 32, but rather a separate axis dedicated to the document contact portion 22, or an axis shared with other components, and the document contact portion 22 may rotate around that axis. In any case, the document contact portion 22 moves (rotates) in conjunction with the movement of the document pressing portion body 21 between the pressing position and the release position.

[0042] To prevent impact noise when the document contact portion 22 comes into contact with the document pressing portion body 21, a cushioning material 25 such as sponge or rubber may be provided on either the document contact portion 22 or the document pressing portion body 21, or both. For example, it may be provided on either the contact point between the locking portion 21a and the locked portion 22a, as long as it is provided so that it is sandwiched between the two when the document contact portion 22 comes into contact with the document pressing portion body 21.

[0043] <If the document holder is not lifted from the pressing position> Figure 13 shows a cross-sectional view of the entire flatbed scanner 1 in Figure 13(a), and an enlarged view of the frame in Figure 13(a) in Figure 13(b). It shows the state in which the document D is uniformly pressed by the document holder 20. To press the document D placed on the document tray 11, an elastic member 23 and a background sheet 24 are provided on the lower surface of the document contact part 22. The elastic member 23 may be made of rubber or sponge. The background sheet 24 is formed in a rectangular shape that is approximately the same as the document tray 11. The color of the background sheet 24 can be selected as white, black, etc., as needed. When the document holder 20 moves to the pressing position shown in Figure 11, the background sheet 24 can uniformly press the document D. At this time, the document contact part 22 is in a housing position, housed within the document pressing unit body 21.

[0044] Furthermore, even if the original document D is a thick document or a double-page spread of a booklet, the original document contact section 22 rotates to the opposite side from the original document placement table 11 and is retracted into the original document pressing section body 21, thereby enabling uniform pressing of the original document D.

[0045] <If the document holder is lifted away from the pressing position> Figure 14(a) shows an enlarged cross-sectional view corresponding to Figure 13(b) when the document holder 20 is lifted from the pressing position, and Figure 14(b) explains the operation of the document contact portion 22 at that time. As shown in Figure 14(a), when the document holder 20 does not close completely and is lifted from the pressing position, the document contact portion 22 can rotate relative to the document pressing body 21 around the hinge axis 32 to a protruding position that protrudes toward the document tray 11 side. As shown in Figure 14(b), the document contact portion 22 protruding toward the document tray 11 side relative to the document pressing body 21 allows the document D to be pressed uniformly.

[0046] Furthermore, to assist in the protrusion of the document contact portion 22, it is advisable to provide a biasing member such as a spring or elastic material on the document holder portion 20.

[0047] Furthermore, in the above embodiment, a rotary damper 34 is provided on the lower housing 60, and pinions 36a and 36b that rotate together with the rotary damper shaft 37 and racks 35a and 35b that mesh with them are provided, but the embodiment is not limited to this. That is, the rotary damper 34 may be attached to the document holder 20, and the rotary damper shaft 37 of the rotary damper 34 may be fixed to the lower housing. However, according to the configuration of this embodiment, the opening and closing operation of the document holder 20 can be adjusted by the meshing state of the racks 35a and 35b and the pinions 36a and 36b and the torque limit value of the rotary damper shaft 37, making the adjustment easy.

[0048] Furthermore, although a flatbed scanner was used as an example of an image reading device in each of the embodiments described above, the present invention is of course not limited thereto, and may be applied to various processing devices equipped with an image reading device (image reading means), such as photocopiers and multifunction printers.

[0049] As a specific example, as shown in Figures 15 and 16, the present invention may be applied to the hinge portion of the upper opening / closing unit of a U-turn path document transport device or an image reading device. In this case, the upper opening / closing unit 201 is rotatably attached to the lower unit via a hinge 301. A rotary damper 341 is provided to mitigate the impact with the lower unit when the upper opening / closing unit 201 moves. The upper unit 201 has a rack 351 arranged concentrically with the hinge shaft 321, which meshes with a pinion 361 located on a rotary damper shaft 371 that passes through the rotary damper 341, and a force acts to mitigate the impact when the upper opening / closing unit 201 moves. [Explanation of Symbols]

[0050] D Manuscript 1. Scanner unit 11. Manuscript holder 12 Top cover 20 Manuscript holding section 21. Main body of the document holder 21a Locked part 22 Document contact area 22a Locking part 23 Elastic members 24 Background sheet 25 Cushioning material 30 hinges 31 Fixed part 32 Hinge axis 33 Rotating part 34 Rotary Damper 35a, 35b racks 36a, 36b pinion 37 Rotary damper shaft 40 Carriage 41 Image reading sensor 42a, 42b axis 43 Engagement hole member 50 Control section 51 Start Scan button 52 Stop scan button 53 Power button 60 Lower cabinet 63 Control board 64 connection cables 65 Carriage lock member 68 Control Unit 69 Driving means 71 Power Cable Connector 72 Communication Cable Connectors

Claims

1. A housing having a document tray on its upper surface on which the document is placed, An image reading means for reading a document placed on the aforementioned document placement platform, A document holder that can be opened and closed between a pressing position for pressing the document placed on the document tray and an opening position for opening the document tray, A hinge that rotatably connects the document holder to the housing and Equipped with, The aforementioned hinge is, A rotating shaft that rotates in conjunction with the opening and closing of the document holder, A rotary damper attached to the aforementioned rotating shaft and a rotating part positioned at a different location on the same axis, A contact portion that contacts the rotating portion in conjunction with the opening and closing of the document holder portion and rotates the rotating portion, It has a connecting part fixed to the document holder part, The contact portions are attached to the connecting portion in pairs at multiple positions on the rotation axis of the hinge. One of the pair of abutting parts is fixed to the connecting part, An image reading device characterized in that the other of the pair of contact portions is mounted so as to be rotatable by a predetermined angle relative to the connecting portion.

2. The image reading device according to claim 1, characterized in that the contact portion has a first gear and the rotating portion has a second gear that meshes with the first gear.

3. The image reading device according to claim 2, characterized in that the first gear is provided in a portion that meshes with the second gear only in a portion of the time while the document holder rotates from the pressing position to the release position.

Images