Image reading device and image forming apparatus

Abstract

To provide an image reading device capable of preventing normal reading of a document from being disturbed, and an image forming apparatus.SOLUTION: An image reading device 20 comprises a reading base 40, a reading head 50, a cover part 22, and a lock mechanism 75. A document to be read is placed on a top face of the reading base 40. The reading head 50 is moved in a first direction A. The cover part 22 is movable between a closing position Z0 and an opening position. The lock mechanism 75 regulates a motion of the cover part 22. When reading the document, the reading head 50 is moved forward from a standby position to one side in the first direction A and moved to a terminal position. After the document is read, the reading head 50 is moved backward from the terminal position to the other side in the first direction A and moved to the standby position. While the reading head 50 is moved from the standby position to the terminal position, the lock mechanism 75 regulates the motion of the cover part 22 moving from the closing position Z0 to the opening position.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to an image reading apparatus and an image forming apparatus.

Background Art

[0002] Patent Document 1 discloses an image forming apparatus including an image reading apparatus. The image reading apparatus of Patent Document 1 includes a document table including a contact glass, a cover that can be opened and closed with respect to the document table, and a reading unit disposed inside the document table. The reading unit includes a carriage that can reciprocate in the sub-scanning direction and a light source supported by the carriage. When a document is read by the reading unit, the light source emits light toward the document placed on the contact glass while moving in the sub-scanning direction.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the image reading apparatus of Patent Document 1, while the reading unit is reading a document on the contact glass (while the light source of the reading unit is moving), if the user opens the cover, the light from the light source will leak to the outside. Also, when the cover is opened, the document will no longer be pressed against the contact glass. When the light from the light source leaks to the outside, or when the document is not pressed against the contact glass, there is a possibility that the reading unit cannot correctly read the document. Therefore, the normal reading of the document by the reading unit may be hindered by the user's operation while the reading unit is reading the document.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide an image reading apparatus and an image forming apparatus that can prevent normal reading of a document from being hindered.

Means for Solving the Problems

[0006] An image reading apparatus according to an aspect of the present invention includes a reading table, a reading head, a cover portion, and a locking mechanism. The reading table has a document to be read placed on its upper surface. The reading head moves in a first direction along the lower surface of the reading table. The cover portion is movable between a closed position that covers the upper surface of the reading table and an open position that opens the upper surface of the reading table. The locking mechanism restricts the movement of the cover portion with respect to the reading table. When the document placed on the reading table is read, the reading head advances from a predetermined standby position to one side in the first direction and moves to a predetermined end position, and after the document is read, it retreats from the end position to the other side in the first direction and moves to the standby position. The locking mechanism restricts the movement of the cover portion from the closed position to the open position while the reading head moves from the standby position to one side in the first direction and moves to the end position.

[0007] An image forming apparatus according to an aspect of the present invention includes the image reading apparatus described above and an image forming unit that forms an image on a recording medium.

Effects of the Invention

[0008] According to the present invention, it is possible to prevent normal reading of a document placed on the reading table from being hindered.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments of an image reading apparatus 20 and an image forming apparatus 10 according to the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[0011] First, with reference to FIG. 1, an image forming apparatus 10 according to an embodiment of the present invention will be described. FIG. 1 is a schematic perspective view of an image forming apparatus 10 including an image reading apparatus 20 according to the embodiment. The image forming apparatus 10 is, for example, a multifunction device having a printer function, a scanner function, and a copy function. The image forming apparatus 10 may have a facsimile function. In the present embodiment, the image forming apparatus 10 forms an image by an electrophotographic method.

[0012] As shown in FIG. 1, in the present embodiment, the image forming apparatus 10 includes an image reading apparatus 20 and an image forming unit 30. In the image forming apparatus 10 of FIG. 1, the image forming unit 30 is disposed below the image reading apparatus 20.

[0013] The image reading apparatus 20 reads a document (not shown in FIG. 1) and generates image data. The image reading apparatus 20 of FIG. 1 includes a cover portion 22, a housing 25, and an operation unit 28. The operation unit 28 includes a display unit such as a liquid crystal display for notifying necessary information to the user, and an input unit such as a keypad for receiving the user's instructions. The operation unit 28 may be a touch panel display in which the display unit and the input unit are integrated.

[0014] The image forming unit 30 forms an image on a recording medium. The recording medium is, for example, paper. The image forming unit 30 preferably includes, for example, an exposure device, a charging device, a photoreceptor drum, a developing device, a cleaning device, a transfer device, and a fixing device. The image forming unit 30 preferably forms an image on the recording medium based on the image data generated in the image reading apparatus 20, for example. Further, the image forming unit 30 may form an image on the recording medium based on the image data transmitted to the image forming apparatus 10 from a device (such as a computer) external to the image forming apparatus 10.

[0015] Next, with reference to FIGS. 1 and 2, the image reading apparatus 20 according to an embodiment of the present invention will be described. FIG. 2 is a schematic plan view of the image reading apparatus 20 according to the embodiment. The image reading apparatus 20 includes a reading table 40, a reading head 50, a cover portion 22, and a locking mechanism 75. Further, the image reading apparatus 20 in FIG. 2 further includes a hinge portion 21, a document conveyance portion 24, and a housing 25.

[0016] The reading table 40 is a table on which a document S to be read is placed on the upper surface. The reading table 40 has a flat and horizontal surface facing upward. The reading table 40 includes a translucent member (for example, contact glass). The document S is placed on the upper surface of the translucent member on the reading table 40.

[0017] The reading head 50 reads the document S to be read. The reading head 50 is disposed below the reading table 40. The reading head 50 moves in a first direction A (sub-scanning direction) along the lower surface of the reading table 40. The reading head 50 has an imaging unit 50a extending in a second direction B (main scanning direction) below the reading table 40. The imaging unit 50a includes, for example, an image sensor of a CIS (Contact Image Sensor) system.

[0018] The CIS system image sensor includes a light emitting portion (not shown) and a light receiving portion (not shown). The light emitting portion includes a plurality of light emitters. The light emitter is, for example, an LED (Light Emitting Diode), and the light emitting portion preferably includes a plurality of color LEDs such as red LEDs, green LEDs, and blue LEDs. The light receiving portion includes an image sensor such as a CMOS (Complementary Metal Oxide Semiconductor) element.

[0019] The imaging unit 50a irradiates light toward the object to be read on the reading table 40 while switching the light of three colors, red, green, and blue, by the light emitting unit, and receives the reflected light reflected by the object to be read by the light receiving unit. The light receiving unit converts the received light into an electrical signal and acquires image data for one line in the second direction B. By collecting the image data for one line in the second direction B (main scanning direction) over the first direction A (sub-scanning direction), the reading head 50 having the imaging unit 50a can read the image written on the object to be read.

[0020] When the document S placed on the reading table 40 is read, the reading head 50 advances from a predetermined reading start position (standby position X0 described later in FIG. 3) to one side in the first direction A and moves to a predetermined reading end position (terminal position X1 described later in FIG. 3). Then, after the document S is read, the reading head 50 retreats from the terminal position X1 to the other side in the first direction A and moves to the standby position X0.

[0021] Note that the document conveyance unit 24 can convey the document S supplied from above the cover unit 22 onto the reading table 40. The document conveyance unit 24 includes, for example, an automatic document feeder (ADF). When the document S is conveyed onto the reading table 40 by the document conveyance unit 24, the reading head 50 does not move, and the document S is read by moving the document S with respect to the imaging unit 50a.

[0022] The housing 25 supports the reading table 40. The hinge portion 21 is provided at an end of the housing 25 (the end in the second direction B in FIG. 2). Since various specific shapes of the hinge portion 21 can be used, the shape of the hinge portion 21 is not shown in detail in the drawings.

[0023] The cover unit 22 is attached to the housing 25 via the hinge portion 21. Since various specific shapes of the cover unit 22 can be used, the shape of the cover unit 22 is not shown in detail in the drawings. Also, in FIG. 1, the cover unit 22 is shown by a virtual line (two-dot chain line).

[0024] The hinge portion 21 connects the cover portion 22 to be swingable with respect to the reading base 40. The cover portion 22 is movable with respect to the reading base 40 by being operated by the user. The cover portion 22 is movable between a position covering the upper surface of the reading base 40 (a closed position Z0 to be described later with reference to FIG. 5) and a position opening the upper surface of the reading base 40 (an open position Z1 to be described later with reference to FIG. 7). In FIGS. 1 and 2, the cover portion 22 is in the closed position Z0.

[0025] The locking mechanism 75 restricts the movement of the cover portion 22 with respect to the reading base 40. The locking mechanism 75 is provided near the hinge portion 21 in FIG. 2. Specifically, the locking mechanism 75 restricts the movement of the cover portion 22 from the closed position Z0 to the open position Z1 while the reading head 50 moves forward from the standby position X0 to one side in the first direction A to the terminal position X1.

[0026] That is, the locking mechanism 75 restricts the movement of the cover portion 22 from being opened while the document S placed on the reading base 40 is being read. By restricting the cover portion 22 from being opened while the document S is being read, it is possible to prevent the light from the light emitting portion of the imaging unit 50a from leaking to the outside. Further, since the cover portion 22 remains closed, the state in which the document S is pressed against the reading base 40 including the contact glass is maintained. Therefore, according to the image reading apparatus 20 and the image forming apparatus 10 of the present embodiment, it is possible to prevent the normal reading of the document S placed on the reading base 40 from being hindered.

[0027] Next, the image reading apparatus 20 will be described in more detail with reference to FIGS. 3 and 4. FIG. 3 is a schematic plan view showing the locking mechanism 75 and the link mechanism 60 of the image reading apparatus 20 according to the present embodiment. FIG. 4 is a schematic plan view of an enlarged part of FIG. 3.

[0028] Figures 3 and 4 show the internal structure of the housing 25 near the end in the second direction B when the cover portion 22 and the reading table 40 are removed from the image reading apparatus 20 of FIG. 2. The planes shown in FIGS. 3 and 4 are horizontal planes below the reading table 40 and parallel to the reading table 40. When the document S placed on the reading table 40 is read, the reading head 50 moves from the standby position X0 to the end position X1 in the horizontal plane shown in FIGS. 3 and 4. Note that the reading head 50 waits at the standby position X0 while the document S is not being read.

[0029] As shown in FIG. 3, the image reading apparatus 20 further includes a link mechanism 60. The link mechanism 60 includes a first link member 61, a second link member 62, and a third link member 63.

[0030] The first link member 61 is provided with a first pivot shaft 61a. The first pivot shaft 61a is perpendicular to the reading table 40. The first link member 61 pivots around the first pivot shaft 61a in a horizontal plane parallel to (and below) the reading table 40. The first link member 61 is provided near the standby position X0 of the reading head 50.

[0031] The second link member 62 is provided at a position separated from the first link member 61 in the first direction A. The second link member 62 is provided with a second pivot shaft 62a. The second pivot shaft 62a is perpendicular to the reading table 40. The second link member 62 pivots around the second pivot shaft 62a in a horizontal plane parallel to (and below) the reading table 40. The second link member 62 is provided near the end position X1 of the reading head 50.

[0032] The third link member 63 connects the first link member 61 and the second link member 62. The third link member 63 extends along the first direction A. The third link member 63 is formed with a first slit 63a and a second slit 63b that extend along the first direction A. And a first fixing pin 64a whose position with respect to the housing 25 is fixed is passed through the first slit 63a. A second fixing pin 64b whose position with respect to the housing 25 is fixed is passed through the second slit 63b. The first slit 63a is provided on the side of the third link member 63 closer to the first link member 61. The second slit 63b is provided on the side of the third link member 63 closer to the second link member 62.

[0033] By passing the first fixing pin 64a and the second fixing pin 64b through the first slit 63a and the second slit 63b respectively, the movement of the third link member 63 is restricted to a translational movement along the first direction A. When the first link member 61 rotates around the first rotation axis 61a, the third link member 63 connected to the first link member 61 translates along the first direction A. And when the third link member 63 translates along the first direction A, the second link member 62 connected to the third link member 63 rotates around the second rotation axis 62a.

[0034] Therefore, the first link member 61 can rotate the second link member 62 through the third link member 63 by rotating around the first rotation axis 61a. Similarly, the second link member 62 can rotate the first link member 61 through the third link member 63 by rotating around the second rotation axis 62a.

[0035] The first link member 61 is disposed between the outer wall of the housing 25 and the reading head 50 in the second direction B within the horizontal plane shown in FIG. 3. The reading head 50 is provided with a head protrusion 51 that protrudes toward the first link member 61 side in the second direction B. When the reading head 50 moves in the first direction A, the head protrusion 51 contacts the first link member 61, causing the first link member 61 to receive the force from the reading head 50 and pivot. Note that the portion of the first link member 61 that contacts the head protrusion 51 is chamfered.

[0036] The second link member 62 is provided with a terminal contact portion 66 that contacts the head protrusion 51 when the reading head 50 moves to the terminal position X1. The terminal contact portion 66 has a shape that protrudes in the second direction B in the second link member 62.

[0037] The locking mechanism 75 is disposed near the first link member 61. The locking mechanism 75 has a locking member 70 held by the housing 25. The locking member 70 is a rod-shaped member having a quadrangular outer peripheral surface in plan view and is disposed within the range in which the first link member 61 pivots. Although not shown in FIG. 3, the locking mechanism 75 further has a locked portion 73 (described later in FIG. 5) formed in the cover portion 22. Hereinafter, among the first link members 61, the portion on the side opposite to the reading head 50 with respect to the first pivot axis 61a, that is, the portion close to the locking member 70, may be referred to as a link tip portion 65.

[0038] The first link member 61 is pivotable between a locked posture P1 (described later in FIG. 8) that contacts the locking member 70 and an unlocked posture P0 that is separated from the locking member 70. While the reading head 50 is waiting at the standby position X0, the first link member 61 is in the unlocked posture P0. Therefore, in FIGS. 3 and 4, the first link member 61 is in the unlocked posture P0.

[0039] In addition, the image reading device 20 shown in FIGS. 3 and 4 further includes a horizontal elastic body 67. The horizontal elastic body 67 presses the first link member 61 in a horizontal plane parallel to the reading base 40 (in the horizontal plane in which the first link member 61 pivots). The horizontal elastic body 67 is, for example, a coil spring. The horizontal elastic body 67 is in an equilibrium state when the reading head 50 is waiting at the standby position X0.

[0040] Also, as shown in FIGS. 3 and 4, the horizontal elastic body 67 is disposed along the first direction A between a portion of the housing 25 that protrudes in the second direction B toward the reading head 50 and the first link member 61. Specifically, the end of the horizontal elastic body 67 is disposed so as to contact a portion of the first link member 61 that is on the side opposite to the link tip 65 with respect to the first pivot axis 61a. However, the horizontal elastic body 67 is in an equilibrium state while the first link member 61 is in the unlocked posture P0 and does not apply an elastic force to the first link member 61.

[0041] The surface of the first link member 61 that contacts the horizontal elastic body 67 is the same surface (the left surface in FIG. 4) that contacts the first link member 61 when the head protrusion 51 moves forward from the standby position X0 to the end position X1 in the first direction A. When the horizontal elastic body 67 is compressed more than when the first link member 61 is in the unlocked posture P0, the horizontal elastic body 67 applies an elastic force to the first link member 61. For example, when the reading head 50 retreats and returns from the end position X1 to the standby position X0, the horizontal elastic body 67 is compressed. Then, the horizontal elastic body 67 applies an elastic force to the first link member 61 to return the first link member 61 to the unlocked posture P0.

[0042] Next, with reference to FIGS. 5, 6, and 7, the lock mechanism 75 will be described in more detail. FIG. 5 is a diagram schematically showing a cross-section taken along line V-V of FIG. 2. In FIG. 5, the cover portion 22 is in the closed position Z0 covering the upper surface of the reading base 40. FIG. 6 is a diagram schematically showing the lock mechanism 75 in a state where the lock member 70 is in the unlocked position Q0. FIG. 6 is a view of the lock mechanism 75 in FIG. 5 as seen from the second direction B. FIG. 7 is a diagram schematically showing a cross-section taken along line V-V of FIG. 2 when the cover portion 22 is in the open position Z1.

[0043] The lock member 70 of the lock mechanism 75 moves between a predetermined lock position Q1 (described later in FIG. 10) and a predetermined unlock position Q0 (described later in FIG. 6). In FIGS. 5, 6, and 7, the lock member 70 is in the unlock position Q0. When the lock member 70 is in the unlock position Q0, the restriction on the movement of the cover portion 22 from the closed position Z0 to the open position Z1 is released. That is, when the lock member 70 is in the unlock position Q0, the user can move (open) the cover portion 22 from the closed position Z0 shown in FIG. 5 to the open position Z1 shown in FIG. 7.

[0044] As shown in FIGS. 5 and 6, the lock member 70 extends in the vertical direction Y. The vertical direction Y is a direction perpendicular to the reading base 40. The lock member 70 moves between the lock position Q1 and the unlock position Q0 by moving in the vertical direction Y.

[0045] As shown in FIG. 5, the locking mechanism 75 has a locked portion 73 formed in the cover portion 22 in addition to the locking member 70 held by the housing 25. The locked portion 73 is arranged to be located above the locking member 70 within the vertical direction Y when the cover portion 22 is in the closed position Z0. And the locked portion 73 has a recess 73a below in the vertical direction Y. The recess 73a faces downward and faces the upper end of the locking member 70 within the vertical direction Y when the cover portion 22 is in the closed position Z0. And the dimensions of the inner wall surface of the recess 73a are set to be slightly larger than the outer peripheral surface of the locking member 70. Therefore, the upper end of the locking member 70 can enter the recess 73a. When the upper end of the locking member 70 enters the recess 73a, the gap between the outer peripheral surface of the upper end of the locking member 70 and the inner wall surface of the recess 73a becomes a very small gap. Further, the locking mechanism 75 further includes a vertical elastic body 79 housed in the recess 73a of the locked portion 73. The vertical elastic body 79 is, for example, a coil spring connected to the cover portion 22. The vertical elastic body 79 is arranged above the locking member 70 in the vertical direction Y in FIG. 5. The vertical elastic body 79 presses the locking member 70 toward the unlock position Q0. Also, the position of the locked portion 73 with respect to the cover portion 22 in a plan view (position within the first direction A and the second direction B) is restricted. Also, the locked portion 73 is slidably held in a direction (vertical direction Y) orthogonal to the plan view. And above the locked portion 73, a retraction elastic body 74 is arranged. The retraction elastic body 74 is a member (biasing means) that biases the locked portion 73 downward in the vertical direction Y. The retraction elastic body 74 is, for example, a coil spring. As shown in FIG. 5, when the cover portion 22 is in the closed position Z0, the locked portion 73 is pressed to the lower limit position in the vertical direction Y by the retraction elastic body 74.

[0046] Also, as shown in FIG. 6, a tapered surface 71 is provided at the lower end portion of the locking member 70 in the vertical direction Y. When the locking member 70 is in the unlock position Q0, the tapered surface 71 of the locking member 70 is arranged within the range where the link tip portion 65 of the first link member 61 swings and moves.

[0047] Further, the locking member 70 of the locking mechanism 75 has a slide hole 72 extending in the vertical direction Y. A slide bar 78 formed in the housing 25 is passed through the slide hole 72. The slide bar 78 has a shape connecting cylinders with different diameters and extends from the housing 25 toward the locking member 70 along the second direction B. The slide bar 78 has a base end portion connected to the housing 25 and a slide bar tip portion 78a located at the tip of the second direction B. The slide bar tip portion 78a has a smaller diameter than the base end portion connected to the housing 25. And the slide bar tip portion 78a is formed to have substantially the same diameter as the width of the slide hole 72. Further, a hook 78c is formed on the head portion of the slide bar tip portion 78a that protrudes from the slide hole 72. The hook 78c protrudes in the radial direction of the slide bar 78. In FIG. 6, among the slide bar 78, the slide bar tip portion 78a that is the end portion in the second direction B is passed through the slide hole 72. A split groove 78b is engraved on the slide bar tip portion 78a. The split groove 78b is engraved along the vertical direction Y with respect to the slide bar tip portion 78a. Therefore, the slide bar tip portion 78a has a shape divided into two in the width direction W intersecting the vertical direction Y with the split groove 78b interposed therebetween. The width direction W is the same direction as the first direction A in FIG. 2 etc. for the entire image reading apparatus 20, but is referred to as the width direction W in the description regarding the locking member 70 alone.

[0048] When passing the slide hole 72 of the locking member 70 through the slide bar tip portion 78a, the slide bar tip portion 78a is elastically deformed in a direction approaching each other in the width direction W by the split groove 78b, and the hook 78c passes through the slide hole 72. When the hook 78c passes through the slide hole 72, the elastic deformation of the slide bar tip portion 78a is eliminated. When the slide bar tip portion 78a passes through the slide hole 72 and the elastic deformation is eliminated, the movement of the locking member 70 in the second direction B is restricted by the base end portion of the slide bar 78 and the hook 78c, and the locking member 70 is supported slidably along the slide hole 72.

[0049] The upper end side of the lock member 70 protrudes upward from the upper surface 25a of the housing 25. Note that the upper surface 25a of the housing 25 is composed of a separate member that is detachable from the housing 25. An opening 25c having substantially the same shape (specifically, a rectangular shape) as the outer peripheral surface of the lock member 70 through which the lock member 70 can be inserted is formed in the upper surface 25a. When the upper surface 25a is attached to the housing 25, the lock member 70 is held in an upright posture by the slide bar tip 78a and the opening 25c, and can slide only in the vertical direction Y.

[0050] When the cover portion 22 is in the closed position Z0 and the lock member 70 is in the unlock position Q0, the lock member 70 has retracted from the locked portion 73, and the upper end of the lock member 70 has not entered the recess 73a of the locked portion 73. Hereinafter, the entry of the upper end of the lock member 70 into the recess 73a of the locked portion 73 may be simply referred to as "the lock member 70 enters the locked portion 73". If the lock member 70 held by the housing 25 does not enter the locked portion 73 formed in the cover portion 22, the cover portion 22 can move relative to the housing 25. Therefore, as shown in FIG. 7, the cover portion 22 can swing relative to the housing 25 via the hinge portion 21 and move to the open position Z1.

[0051] Next, with reference to FIGS. 8, 9, 10, and 11, the movement of the lock member 70 to the lock position Q1 when the reading head 50 advances to one side in the first direction A will be described. FIG. 8 is a schematic plan view showing a state in which the reading head 50 starts to advance from the standby position X0. FIG. 9 is a schematic perspective view showing a state in which the reading head 50 starts to advance from the standby position X0. FIG. 10 is a diagram schematically showing the lock mechanism 75 when the lock member 70 is in the lock position Q1. FIG. 11 is a diagram schematically showing a cross section taken along the line V-V of FIG. 2 when the lock member 70 is in the lock position Q1.

[0052] As shown in FIGS. 8 and 9, when the reading head 50 starts to move forward to one side in the first direction A, the head projection 51 of the reading head 50 contacts the first link member 61. When the head projection 51 contacts the first link member 61, the first link member 61 receives the force from the reading head 50 and pivots from the unlocked posture P0 to the locked posture P1 in contact with the lock member 70. When the first link member 61 pivots to the locked posture P1, as shown in FIGS. 8 and 9, the link tip 65 enters below the lock member 70.

[0053] Then, as shown in FIG. 10, when the link tip 65 enters below the lock member 70, the tapered surface 71 at the lower end of the lock member 70 receives the upward pushing force from the link tip 65, and the lock member 70 is moved upward in the vertical direction Y. And when the lock member 70 rides on the upper surface of the link tip 65, the lock member 70 is in a state of moving to the locked position Q1. Although the vertical elastic body 79 of the locking mechanism 75 presses the lock member 70 downward toward the unlocked position Q0, while the link tip 65 is entering below the lock member 70, the lock member 70 cannot move downward and remains at the locked position Q1.

[0054] As shown in FIG. 10, when the cover portion 22 is in the closed position Z0 and the locking member 70 is in the locking position Q1, the upper end of the locking member 70 enters the locked portion 73. The gap between the outer peripheral surface of the locking member 70 and the inner wall portion of the locked portion 73 is configured to be minute. Therefore, when the upper end of the locking member 70 enters the locked portion 73 and the cover portion 22 attempts to swing relative to the housing 25 via the hinge portion 21 and move from the closed position Z0 to the open position Z1, the inner wall portion of the locked portion 73 interferes with the outer peripheral surface of the locking member 70. The inner wall portion of the recess 73a of the locked portion 73 formed in the cover portion 22 interferes with the outer peripheral surface of the locking member 70 held by the housing 25, thereby inhibiting the movement of the cover portion 22 to the open position Z1. Therefore, the outer peripheral surface of the locking member 70 that has entered the recess 73a interferes with the inner wall surface of the recess 73a, so that the cover portion 22 cannot move relative to the housing 25, and the movement of the cover portion 22 from the closed position Z0 to the open position Z1 is restricted.

[0055] That is, as shown in FIG. 11, when the lock member 70 is in the locked position Q1, the upper end of the lock member 70 enters the locked portion 73, thereby restricting the movement of the cover portion 22 from the closed position Z0 to the open position Z1. Therefore, according to the present embodiment, the restriction of the movement of the cover portion 22 is realized mechanically (hardware-wise). When the cover portion 22 moves from the open position Z1 to the closed position Z0, if the lock member 70 is in the unlocked position Q0, the cover portion 22 can move to the closed position Z0 without interfering with the locked portion 73. On the other hand, when the lock member 70 is in the locked position Q1 and the cover portion 22 attempts to move from the open position Z1 to the closed position Z0, the locked portion 73 interferes with the lock member 70. When the locked portion 73 interferes with the lock member 70, the locked portion 73 retreats upward against the biasing force of the retreat elastic body 74, enabling the cover portion 22 to move to the closed position Z0. After the cover portion 22 moves to the closed position Z0, the locked portion 73 is pushed down by the retreat elastic body 74, and the locked portion 73 is rearranged above the lock member 70. That is, even when the lock member 70 is in the locked position Q1, it is possible for the cover portion 22 to move from the open position Z1 to the closed position Z0.

[0056] As described above, when the reading head 50 advances from the standby position X0 to one side in the first direction A, the first link member 61 receives the force from the reading head 50 and pivots from the unlocked posture P0 to the locked posture P1. Then, by pivoting to the locked posture P1, the first link member 61 moves the lock member 70 from the unlocked position Q0 to the locked position Q1. And when the lock member 70 is in the locked position Q1, it restricts the movement of the cover portion 22 from the closed position Z0 to the open position Z1.

[0057] More specifically, when the reading head 50 moves forward from the standby position X0 to one side in the first direction A, the first link member 61 pivots from the unlocked posture P0 to the locked posture P1 and enters below the locking member 70. By entering below the locking member 70, the first link member 61 pushes the locking member 70 upward in the vertical direction Y and moves the locking member 70 to the locked position Q1.

[0058] According to the present embodiment, when the reading head 50 moves forward, the first link member 61 mechanically (hardware-wise) moves the locking member 70 to the locked position Q1. Therefore, in order to realize the restriction of the movement of the cover portion 22, it is not necessary to add software to the image reading apparatus 20.

[0059] Next, with reference to FIGS. 12 and 13, the case where the reading head 50 moves to the end position X1 will be described. FIG. 12 is a schematic plan view showing a state where the reading head 50 has advanced near the end position X1. FIG. 13 is a schematic plan view showing a state where the reading head 50 has advanced to the end position X1.

[0060] When the first link member 61 pivots to the locked posture P1, the second link member 62 also pivots through the third link member 63. As shown in FIG. 12, when the first link member 61 is in the locked posture P1, the second link member 62 is in a state where the end contact portion 66 is tilted toward the reading head 50 side (the other side in the first direction A as viewed from the third link member 63).

[0061] The state where the first link member 61 is in the locked posture P1 continues from when the reading head 50 departs from the standby position X0 until it reaches the end position X1. Therefore, while the reading head 50 moves from the standby position X0 to the end position X1, that is, while the document S on the reading table 40 is being read, the cover portion 22 is prevented from opening.

[0062] As shown in FIG. 12, when the reading head 50 moves forward to one side in the first direction A and approaches the end position X1, the head protrusion 51 of the reading head 50 contacts the end contact portion 66. Then, when the reading head 50 further moves forward and reaches the end position X1 as shown in FIG. 13, the second link member 62 rotates by receiving the force from the reading head 50. When the second link member 62 rotates, the first link member 61 also rotates through the third link member 63. Then, the first link member 61 that was in the locked posture P1 is rotated to the unlocked posture P0 as shown in FIG. 13.

[0063] When the first link member 61 rotates to the unlocked posture P0, the link tip portion 65 of the first link member 61 moves away from below the lock member 70. Then, the vertical elastic body 79 presses the lock member 70 downward and moves the lock member 70 from the locked position Q1 to the unlocked position Q0 shown in FIG. 5.

[0064] Therefore, when the reading head 50 moves to the end position X1, the second link member 62 rotates by receiving the force from the reading head 50, and rotates the first link member 61 from the locked posture P1 to the unlocked posture P0 through the third link member 63. And the second link member 62 moves the lock member 70 from the locked position Q1 to the unlocked position Q0 by rotating the first link member 61 to the unlocked posture P0.

[0065] Also, when the reading head 50 moves to the end position X1, when the first link member 61 rotates from the locked posture P1 to the unlocked posture P0 and moves away from below the lock member 70, the vertical elastic body 79 moves the lock member 70 to the unlocked position Q0.

[0066] When the reading head 50 reaches the end position X1, the reading of the document S on the reading table 40 is completed. Therefore, it is preferable that the cover part 22 can be opened when the reading head 50 reaches the end position X1. According to the present embodiment, when the reading head 50 reaches the end position X1, the locking member 70 is mechanically (hardware-wise) moved to the unlocked position Q0. Thus, there is no need to add software to the image reading apparatus 20 to realize the release of the restriction on the movement of the cover part 22.

[0067] Next, with reference to FIGS. 14 and 3, a case where, after the document S has been read, the reading head 50 retreats from the end position X1 to the other side in the first direction A and moves to the standby position X0 will be described. FIG. 14 is a schematic plan view showing a state where the reading head 50 has retreated close to the standby position X0.

[0068] As shown in FIG. 14, when the reading head 50 retreats to the other side in the first direction A and moves close to the standby position X0, the head projection 51 of the reading head 50 contacts the first link member 61 from one side in the first direction A. Then, the first link member 61 pivots from the unlocked posture P0 in a direction to compress the horizontal elastic body 67.

[0069] When the reading head 50 further retreats from the state shown in FIG. 14 and moves to the standby position X0 shown in FIG. 3, the first link member 61 that has been pivoting in the direction to compress the horizontal elastic body 67 receives a pressing force in the direction in which the horizontal elastic body 67 returns to the equilibrium state. Since the horizontal elastic body 67 is in the equilibrium state when the reading head 50 is standing by at the standby position X0, when the reading head 50 moves to the standby position X0, the posture of the first link member 61 is returned to the posture in which the horizontal elastic body 67 is in the equilibrium state. That is, when the reading head 50 retreats and moves to the standby position X0, the first link member 61 is returned to the unlocked posture P0 that does not compress the horizontal elastic body 67.

[0070] Therefore, after the reading head 50 moves from the standby position X0 to the terminal position X1 and then returns to the standby position X0 again, the state of the link mechanism 60 is automatically returned to the state before the reading head 50 departs from the standby position X0.

[0071] In addition, in this embodiment, the locking member 70 moves between the locked position Q1 and the unlocked position Q0 by moving in the vertical direction Y perpendicular to the reading base 40. However, the moving direction of the locking member 70 does not necessarily have to be the vertical direction Y. The locking member 70 only needs to be able to switch between restricting and releasing the movement of the cover portion 22 in response to the turning of the first link member 61. For example, the locking member 70 may move in the first direction A or the second direction B in response to the turning of the first link member 61.

[0072] Also, in this embodiment, a vertical elastic body 79 that presses the locking member 70 toward the unlocked position Q0 is provided, but the vertical elastic body 79 does not necessarily have to be provided. As long as the locking member 70 moves to the unlocked position Q0 when the reading head 50 reaches the terminal position X1 (when the reading of the document S is completed). For example, a mechanical device or an electric circuit that moves the locking member 70 in conjunction with a switch provided at the terminal position X1 may be provided.

[0073] Also, in this embodiment, the interference between the locking member 70 and the locked portion 73 restricts the movement of the cover portion 22 from the closed position Z0 to the open position Z1. However, the method of restricting the movement of the cover portion 22 is not limited to the method of this embodiment. As long as the movement of the cover portion 22 is restricted when the locking member 70 is in the locked position Q1. For example, when the locking member 70 is in the locked position Q1, a mechanical device or an electric circuit that acts on the hinge portion 21 to restrict the movement of the cover portion 22 may be provided.

[0074] The embodiments of the present disclosure have been described above with reference to the drawings. However, the present disclosure is not limited to the above embodiments, and can be implemented in various aspects without departing from the gist of the present disclosure. The drawings schematically show each component mainly for easy understanding, and the thickness, length, number, interval, etc. of each illustrated component are different from the actual ones for convenience of drawing creation. Further, the materials, shapes, dimensions, etc. of each component shown in the above embodiments are examples and are not particularly limited, and various changes can be made without substantially departing from the configuration of the present disclosure.

Industrial Applicability

[0075] The present invention provides an image reading apparatus and an image forming apparatus, and has industrial applicability.

Explanation of Signs

[0076] 10 Image forming apparatus 20 Image reading apparatus 22 Cover part 24 Document conveyance part 25 Housing 40 Reading table 50 Reading head 60 Link mechanism 61 First link member 61 First pivot axis 62 Second link member 62a Second pivot axis 63 Third link member 67 Horizontal elastic body 70 Lock member 72 Slide hole 73 Locked part 74 Retraction elastic body 75 Lock mechanism 78 Slide bar 79 Vertical elastic body

Claims

1. A reading table on which a manuscript to be read is placed on the upper surface, A reading head that moves in a first direction along the lower surface of the reading table, A cover portion movable between a closed position covering the upper surface of the reading table and an open position opening the upper surface of the reading table, A locking mechanism that restricts the movement of the cover portion with respect to the reading table is provided, When the manuscript placed on the reading table is read, the reading head advances from a predetermined standby position to one side in the first direction and moves to a predetermined end position, and after the manuscript is read, it retreats from the end position to the other side in the first direction and moves to the standby position, The locking mechanism restricts the movement of the cover portion from the closed position to the open position while the reading head advances from the standby position to one side in the first direction and moves to the end position, an image reading apparatus.

2. A first link member that pivots around a first pivot axis perpendicular to the reading table in a horizontal plane parallel to the reading table, a second link member provided at a position separated from the first link member in the first direction and pivoting around a second pivot axis perpendicular to the reading table in the horizontal plane, and a third link member connecting the first link member and the second link member, further comprising a link mechanism having, The locking mechanism has a lock member that moves between a predetermined locked position and a predetermined unlocked position, The first link member is pivotable between a locked posture in contact with the lock member and an unlocked posture separated from the lock member, When the reading head advances from the standby position to one side in the first direction, the first link member receives a force from the reading head and pivots from the unlocked posture to the locked posture, thereby moving the lock member from the unlocked position to the locked position, When the reading head moves to the end position, the second link member receives a force from the reading head and pivots, thereby pivoting the first link member from the locked posture to the unlocked posture through the third link member and moving the lock member from the locked position to the unlocked position, The image reading apparatus according to claim 1, wherein when the lock member is in the locked position, the movement of the cover portion from the closed position to the open position is restricted, and when the lock member is in the unlocked position, the restriction on the movement of the cover portion from the closed position to the open position is released.

3. The cover portion has a portion to be locked that faces the lock member within a vertical direction perpendicular to the reading table when the cover portion is in the closed position. The lock member moves between the locked position where it enters the portion to be locked and the unlocked position where it retracts from the portion to be locked by moving in the vertical direction. The image reading apparatus according to claim 2, wherein when the reading head advances from the standby position to one side in the first direction, the first link member pivots from the unlocked posture to the locked posture and enters below the lock member, thereby pushing up the lock member in the upward direction of the vertical direction and moving the lock member to the locked position.

4. The lock mechanism further includes a vertical elastic body that presses the lock member toward the unlocked position. The image reading apparatus according to claim 3, wherein when the reading head moves to the terminal position, when the first link member pivots from the locked posture to the unlocked posture and leaves from below the lock member, the vertical elastic body moves the lock member to the unlocked position.

5. The image reading apparatus further includes a housing that supports the reading table, and a hinge portion provided at an end of the housing and connecting the cover portion so as to be swingable with respect to the reading table. The portion to be locked has a recess into which the lock member can enter. When the lock member is in the locked position, the lock member enters the recess, and when the cover portion swings via the hinge portion and attempts to move from the closed position to the open position with respect to the housing, the outer peripheral surface of the lock member that has entered the recess interferes with the inner wall surface of the recess, thereby restricting the movement of the cover portion from the closed position to the open position. The image reading apparatus according to claim 4.

6. The image reading apparatus further includes a retracting elastic body that is disposed above the portion to be locked and biases the portion to be locked downward in the vertical direction. When the lock member is in the locked position, if the cover portion attempts to move from the open position to the closed position, the locked portion moves upward against the biasing force of the retracting elastic body, enabling the cover portion to move to the closed position. The image reading apparatus according to claim 5.

7. The image reading apparatus further includes a horizontal elastic body that presses the first link member within the horizontal plane. The horizontal elastic body is in an equilibrium state when the reading head is waiting at the standby position. The image reading apparatus according to claim 2.

8. An image forming apparatus comprising the image reading apparatus according to any one of claims 1 to 7, and an image forming unit that forms an image on a recording medium. ​

Images