JP6481965B2 - Document conveying apparatus and image forming apparatus - Google Patents

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document conveying device that conveys a document made of paper or the like, and an image forming apparatus such as a copying machine, a printer, a facsimile, or a complex machine or a printing machine including the same.

  Conventionally, in an image forming apparatus such as a copying machine, a printer, or a printing machine, as a document conveying device that conveys a document, documents stacked on a document placing portion (document table) are sequentially fed from the top, The image reading unit reads the image of the document while sandwiching and conveying the document between the image reading surface of the image reading unit (reading unit) and the contact member (reading roller), and then the document is output to the document discharge unit (discharge unit). A paper tray that is sequentially discharged and stacked on a paper tray is widely used (see, for example, Patent Document 1).

On the other hand, Patent Document 1 discloses a technique in which an image reading unit is configured as a single image reading unit that can be attached to and detached from a document conveying device in order to improve maintainability of the image reading unit.
Specifically, the image reading unit is guided by a guide member provided in the main body of the document conveying device, and attaches and detaches the width direction of the document conveying device (a direction perpendicular to the conveying direction in which the document is conveyed). The direction is configured to be attached to and detached from the document feeder. Further, in conjunction with the operation of attaching / detaching the image reading unit to / from the document conveying device, the rotating member (biasing member) is arranged so that the contact member (reading roller) is separated from the image reading unit (reading unit). The release member is rotated.

The conventional document conveying device disclosed in Patent Document 1 or the like is in contact with the image reading surface of the image reading unit (reading roller) in conjunction with the operation of attaching / detaching the image reading unit to / from the document conveying device. ) Is rotated such that the image reading unit is separated, the image reading surface is brought into sliding contact with the contact member when the image reading unit is attached / detached, and the attaching / detaching operability is deteriorated. It is possible to expect the effect of reducing defects and defects that cause scratches on the image reading surface.
However, the conventional document conveying device disclosed in Patent Document 1 and the like is provided with a rotating member (biasing release member) for separating the contact member (reading roller) from the image reading surface of the image reading unit. As a result, the equipment has become larger and more expensive.

  The present invention has been made to solve the above-described problems, and has a relatively simple configuration and interlocks with an operation of attaching and detaching the image reading unit to and from the document conveying device. An object of the present invention is to provide an original conveying apparatus and an image forming apparatus in which a contact member is separated from a reading surface.

  A document conveying apparatus according to a first aspect of the present invention is a document conveying apparatus that conveys a document, and is detachably installed in the apparatus with a width direction orthogonal to the document conveying direction as a detaching direction. An image reading unit that reads image information of the document; and an abutting member that is urged by an urging member and abuts on an image reading surface of the image reading unit, and the image reading unit includes the image reading unit. Projecting toward the contact member side with respect to the image reading surface at a position on the back side in the mounting direction with respect to the reading surface with respect to the reading surface, and contacting the contact member in conjunction with an attaching / detaching operation with respect to the device. A protrusion for pushing the abutting member against the urging force of the urging member is provided.

  According to the present invention, the abutting member is separated from the image reading surface of the image reading unit in conjunction with the operation of attaching and detaching the image reading unit to and from the document conveying device with a relatively simple configuration. An original conveying apparatus and an image forming apparatus can be provided.

1 is an overall configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention. 1 is a configuration diagram illustrating a document conveying device. FIG. FIG. 4A is a perspective view showing the inside of the document conveying apparatus in a state where the image reading unit is mounted, and FIG. 4B is a perspective view showing the appearance of the document conveying apparatus in a state where the image reading unit is attached / detached. FIG. 3 is a schematic diagram showing the inside of the document conveying device with the image reading unit mounted in the width direction. It is a block diagram which shows an image reading unit. It is a perspective view which shows an image reading unit. FIG. 6 is a diagram illustrating an operation of a main part when the image reading unit is detached from the document conveying device. FIG. 5 is a diagram illustrating an operation of a main part when an image reading unit is mounted on a document conveying device. FIG. 10 is a perspective view showing the inside of the document conveying apparatus in a state where an image reading unit is mounted as a modified example. FIG. 10 is a diagram illustrating a main part of the document conveying device in a state where the image reading unit in FIG. 9 is mounted.

Embodiment.
Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the part which is the same or it corresponds, The duplication description is simplified or abbreviate | omitted suitably.

First, the overall configuration and operation of the image forming apparatus 1 will be described with reference to FIG.
In FIG. 1, 1 is a copying machine as an image forming apparatus, 2 is a first image reading unit that optically reads image information on the front side of an original D, and 3 is based on image information read by the image reading units 2 and 80. An exposure unit for irradiating the photosensitive drum 5 with the exposure light L, 4 is an image forming unit for forming a toner image (image) on the photosensitive drum 5, and 7 is a toner image formed on the photosensitive drum 5. A transfer unit (image forming unit) for transferring to a sheet P (sheet) 10 is a document conveying device that conveys the document D set on the document placing unit 61 to the image reading units 2 and 80 and discharges it to the document discharge unit 62. , 12 to 14 are sheet feeding units in which the sheet P is stored, 17 is a registration roller (timing roller) that conveys the sheet P toward the transfer unit 7, and 20 is a toner image (unfixed image) carried on the sheet P. ) Is fixed to the fixing device 20. A fixing roller, 22 is a pressure roller installed in the fixing device 20, 31 is a paper discharge tray on which the paper P discharged from the image forming apparatus main body 1 is stacked, and 80 is an optical device for image information on the back surface of the document D. 1 shows an image reading unit (second image reading unit) that automatically reads.

With reference to FIG. 1, an operation during normal image formation in the image forming apparatus main body 1 will be described.
First, the document D is transported (feeded) from the document placing unit 61 in the document transporting apparatus 10 and passes through the position of the first image reading unit 2. At this time, the first image reading unit 2 optically reads the image information on the front side of the document D passing above.
Then, the optical image information read by the first image reading unit 2 is converted into an electrical signal and then transmitted to the exposure unit 3 (writing unit). Then, exposure light L such as laser light based on the image information of the electrical signal is emitted from the exposure unit 3 toward the photosensitive drum 5 of the image forming unit 4.

On the other hand, in the image forming unit 4, the photosensitive drum 5 is rotated in the clockwise direction in the drawing, and image information is transferred onto the photosensitive drum 5 through a predetermined image forming process (charging process, exposure process, development process). An image (toner image) corresponding to is formed.
Thereafter, the image formed on the photosensitive drum 5 is transferred onto the paper P conveyed by the registration roller 17 at the position of the transfer unit 7.

On the other hand, the sheet P conveyed to the transfer unit 7 (image forming unit) operates as follows.
First, one of the plurality of sheet feeding units 12 to 14 of the image forming apparatus main body 1 is automatically or manually selected (for example, the uppermost sheet feeding unit 12 in the apparatus main body 1 is selected). ) Then, the uppermost sheet P of the paper P stored in the paper feeding unit 12 is fed by a paper feeding mechanism 52 (consisting of a feed roller, a pickup roller, a backup roller, etc.), and is transported. It is conveyed toward. Thereafter, the sheet P passes through a conveyance path in which a plurality of conveyance rollers are arranged, and reaches the position of the registration roller 17.

The sheet P that has reached the position of the registration roller 17 is conveyed toward the transfer unit 7 (image forming unit) at the same timing in order to align with the image formed on the photosensitive drum 5.
Then, after the transfer process, the sheet P passes through the position of the transfer unit 7 and then reaches the fixing device 20 through the conveyance path. The sheet P that has reached the fixing device 20 is fed between the fixing roller 21 and the pressure roller 22, and the toner image is fixed by the heat received from the fixing roller 21 and the pressure received from both members 21 and 22. (This is a fixing process). The paper P after the fixing process on which the toner image has been fixed is delivered from between the fixing roller 21 and the pressure roller 22 (a fixing nip), and then is discharged from the image forming apparatus main body 1 to be an output image. As shown in FIG.
Thus, a series of image forming processes is completed.

  In the case of performing image formation based on the back side image in addition to the front side of the document D, in the document conveying apparatus 10, the image reading unit 80 (second image) is passed through the position of the first image reading unit 2. When passing through the position of the image reading unit), the image information on the back surface of the document D that passes below is optically read by the image reading unit 80. Then, similarly to the image forming process based on the front side image, the optical image information read by the image reading unit 80 is transmitted to the exposure unit 3, and the image forming process based on the optical image information is performed. .

Next, the configuration and operation of the document feeder 10 will be described in detail with reference to FIG.
As shown in FIG. 2, the document conveying device 10 includes a document placement unit 61 (document table), a first image reading unit 2, an image reading unit 80 (second image reading unit), and a contact member 90 (guide plate). , Document discharge unit 62 (discharge tray), pickup roller 63, separation conveyance roller pair 64 (feed roller and separation roller), a plurality of conveyance roller pairs 65-68, discharge roller pair 69 (discharge roller pair), conveyance The upper guide plate 71, the first transport lower guide plate 72, the second transport lower guide plate 73, and the like.

Here, the document placing portion 61 is formed with a space opened upward, and is configured so that the user can place the document D with the front side facing upward from above (a plurality of sheets). A stack of originals D can be stacked).
The document discharge section 62 is installed below the document placement section 61 and is configured to discharge and place the document D after the image is read by the image reading sections 2 and 80. (A plurality of documents D are configured to be stacked).

  Further, in the conveyance path from the document placing unit 61 to the document discharge unit 62, a pickup roller 63, a separation conveyance roller pair 64, a first conveyance roller pair 65 (abutting roller pair), a first conveyance roller, in order from the upstream side in the conveyance direction. 2 conveyance roller pair 66 (reading entrance roller pair), 3rd conveyance roller pair 67 (1st reading exit roller pair), 4th conveyance roller pair 68 (2nd reading exit roller pair) as a downstream conveyance roller pair, discharge A roller pair 69 is installed. These roller members 63 to 69 convey the document D placed on the document placing unit 61 toward the image reading units 2 and 80, and convey the document D after image reading toward the document discharge unit 62. It functions as a conveying means.

Further, as shown in FIG. 2, a plurality of guide plates for guiding the conveyance of the document D are provided on the conveyance path formed by these roller members 63 to 69 and the side facing the front surface of the document D. It is installed substantially parallel to the side facing the back surface.
In the present embodiment, the guide plates 71 to 73 installed in the conveyance path between the fourth conveyance roller pair 68 and the discharge roller pair 69 are on the side facing the front surface of the document D and the back surface. They are not formed so as to be substantially parallel to the opposing sides. Specifically, the second conveyance lower guide plate 73 is formed such that the upstream side in the conveyance direction overlaps in the conveyance direction at a position lower than the first conveyance lower guide plate 72. Further, the transport upper guide plate 71 is formed to be curved in a convex shape upward.

Here, the plurality of conveyance roller pairs 65 to 68 (particularly, the three conveyance roller pairs 66 to 68 related to the reading accuracy in the image reading units 2 and 80) are used to copy the document D in the image reading units 2 and 80. Are transported at a constant transport speed (constant speed). The first image reading unit 2 faces the front surface of the document D in the conveyance path between the second conveyance roller pair 66 (reading entrance roller pair) and the third conveyance roller pair 67 (first reading exit roller pair). The image reading unit 80 (second image reading unit) is configured such that the document D is conveyed on the conveyance path between the third conveyance roller pair 67 and the fourth conveyance roller pair 68 (second reading exit roller pair). It is arranged so as to face the back surface.
The discharge roller pair 69 is on the downstream side in the transport direction with respect to the fourth transport roller pair 68 serving as the downstream transport roller pair located on the most downstream side in the transport direction among the plurality of transport roller pairs 65 to 68. It is arranged at the position of the outlet. Then, the document D after the image is read by the image reading units 2 and 80 is conveyed by the discharge roller pair 69 and discharged (stacked) toward the document discharge unit 62.

Hereinafter, a basic operation in the document conveying apparatus 10 configured as described above will be described.
First, in the document placing portion 61, the document D (at least with an image formed on the front side) is stacked with the front side facing up. When an instruction to read an image of the document D (copy instruction) is issued by operating an operation panel (not shown), the pickup roller 63 sequentially separates the pair of separation conveyance rollers from the document D on the document placement unit 61. It is conveyed toward 64. At this time, there is a possibility that a plurality of originals D are conveyed toward the separation conveyance roller pair 64, but only the uppermost original D is separated by the FRR separation in the separation conveyance roller pair 64, and the downstream side. It will be sent to the transport route.

Thereafter, the document D transported to the transport path hits the nip of the first transport roller pair 65 (abutting roller pair) in a state where the rotation is stopped, and skew correction (skew correction) is performed. Thereafter, the skew-corrected document D is transported downstream by the first transport roller pair 65 that has started to rotate, and after passing through the position of a document detection sensor (registration sensor) (not shown), the second transport roller pair 66. Is conveyed to the position of the first image reading unit 2. Then, the image on the front side of the document D is optically read at the position of the first image reading unit 2.
Thereafter, the document D on which the image has been read is conveyed to the position of the image reading unit 80 (second image reading unit) by the second conveying roller pair 66 and the third conveying roller pair 67. Then, the image on the back surface of the document D is optically read at the position of the image reading unit 80. Note that when the image information on the back side of the document D is not read (when the mode for reading only the image information on the front side is set), the image reading unit 80 as described above reads the image. Without doing so, the document D passes through the position of the image reading unit 80 as it is.
Thereafter, the document D is transported to the position of the discharge roller pair 69 by the third transport roller pair 67 and the fourth transport roller pair 68 (downstream transport roller pair). Then, the paper is discharged onto the original discharge unit 62 by the conveyance by the discharge roller pair 69.
When a plurality of documents D are stacked on the document placement unit 61 and image formation is performed on the documents D, the plurality of documents D on the document placement unit 61 are continuously arranged at intervals. Thus, a series of document conveying operations as described above are repeated.

Hereinafter, a characteristic configuration and operation of the document conveying device 10 according to the present embodiment will be described in detail with reference to FIGS.
As described above with reference to FIG. 2, the document conveying device 10 according to the present embodiment is provided with the image reading unit 80 (second image reading unit) that reads the image information (image) of the document D. .
In the present embodiment, the image reading unit 80 can be attached to and detached from the document conveying apparatus 10 with the width direction (perpendicular to the plane of FIG. 2) perpendicular to the conveying direction of the document D as the attachment / detachment direction. is set up. Specifically, as shown in FIGS. 3A and 4, the image reading unit 80 includes two main body side plates 101 installed at both ends in the width direction so as to function as a part of the casing of the document feeder 10. , 102 (a front side plate and a rear side plate). Specifically, in the image reading unit 80, a boss portion 84a formed on one end side in the width direction (the left side in FIG. 4 and the rear side in the mounting direction) is a hole in the main body side plate 102 (rear side plate). The main body side plate 101 (front side) is positioned through a positioning hole portion of the face plate 81 formed on the other end side in the width direction (right side in FIG. 4 and on the front side in the mounting direction). The screw 120 is screwed into the female screw portion of the side plate) and positioned.
When performing maintenance or replacement of the image reading unit 80, as shown in FIG. 3B, the image reading unit 10 is read with the screw 120 at the position of the face plate 81 removed. The unit 80 is attached and detached in the width direction (in the direction of the double arrow in FIG. 3B).

Here, referring to FIGS. 5 and 6, the image reading unit 80 includes a CIS 82 (contact image sensor), a contact glass 83, a housing 84, a cover 85, a face plate 81, and the like as the main part of the image reading unit. It consists of
The CIS 82 is a well-known one, and is housed in a substantially sealed space in the image reading unit 80 in order to prevent adhesion of foreign matters such as dust.
The contact glass 83 is a member formed of a light-transmitting material such as transparent glass, and its surface functions as an image reading surface 83a (original transport surface). That is, the document D conveyed along the image reading surface 83a (document conveying surface) is irradiated with light from the light emitting portion of the CIS 82 via the contact glass 83, and the light reflected by the document D is contact glass. By being received by the light receiving unit of the CIS 82 via 83, the image information of the document D is read by the CIS 82.
The housing 84 is formed of a resin material having a high mechanical strength and functions as a main part of the housing of the image reading unit 80. A contact glass 83 is fixedly held at the bottom of the housing 84, A face plate 81 is fixed and held at the end in the width direction. A cover 85 is held on the upper portion of the housing 84 by screw fastening.

4 and the like, the document conveying device 10 according to the present embodiment is abutted against the image reading surface 83a of the image reading unit 80 by being urged by a compression spring 91 as an urging member. A member 90 is provided.
Specifically, the contact member 90 extends in the width direction (the left-right direction in FIG. 4 and the vertical direction in FIG. 2) so as to face the image reading surface 83a of the image reading unit 80. It is a plate-like member made of a galvanized steel plate or the like having a surface 90a, and functions as a guide plate for guiding the document D passing through the position of the image reading surface 83a. Referring to FIGS. 7, 8 and the like, the abutting member 90 protrudes toward the image reading surface 83a at the both ends in the width direction at the abutting portions 90b (outside the range of the paper passing area of the document D). Formed.) Is formed. Then, the contact members 90 are urged toward the image reading surface 83a by the compression springs 91 respectively installed at both ends in the width direction, and the abutting portion 90b directly abuts against the image reading surface 83a, whereby the image A predetermined gap is set between the reading surface 83a (original transport surface) and the transport surface 90a. The gap between the image reading surface 83a and the conveyance surface 90a does not hinder the conveyance of the document D, the document D does not flutter and has high adhesion to the image reading surface 83a, and the image is read by the image reading unit 80 (CIS 82). Is set to be read satisfactorily.

Here, with reference to FIGS. 4 and 7, etc., in the present embodiment, the image reading unit 80 has a back side in the mounting direction with respect to the document conveying device 10 with respect to the image reading surface 83a (left side in FIG. 4). ) To the position of the contact member 90 with respect to the image reading surface 83a, and in contact with the contact member 90 in conjunction with the attaching / detaching operation with respect to the document conveying device 10, the compression spring 91 (attached). A protrusion 84b that pushes the abutting member 90 against the urging force of the urging member) is provided.
Specifically, the protrusion 84b is formed so as to protrude downward on one end side in the width direction at the bottom of the housing 84 (on the left side in FIG. 4 and on the rear side in the mounting direction).
Referring to FIG. 7, the protrusion 84 b has a first inclined portion 84 b 2 that is inclined away from the contact member 90 from the top 84 b 1 toward the back in the mounting direction, and from the top 84 b 1 toward the front in the mounting direction. And a second inclined portion 84b3 that is inclined so as to be away from the contact member 90.

  On the other hand, as shown in FIG. 8, the contact member 90 (guide plate) is formed with a first engagement portion 90c that engages with the first inclined portion 84b2 of the protrusion 84b at a position on the front side in the mounting direction. As shown in FIG. 7, a second engaging portion 90d that engages with the second inclined portion 84b3 of the protruding portion 84b is formed at a position on the back side in the mounting direction. These engaging portions 90c and 90d are R-shaped bent portions formed by bending a sheet metal, and are portions where the conveyance surface 90a and a surface orthogonal to the conveyance surface 90a intersect.

With such a configuration, when the image reading unit 80 mounted on the document conveying device 10 is removed from the document conveying device 10, as shown in FIGS. The member 90 will operate.
Specifically, as shown in FIG. 7A, first, when the image reading unit 80 is mounted on the document conveying device 10, the protrusion 84b of the image reading unit 80 is in contact with the contact member 90. There is no state. At this time, the contact member 90 (the abutting portion 90b) is in contact with the image reading surface 83a of the image reading unit 80.

On the other hand, as shown in FIG. 7B, when the image reading unit 80 is moved in the direction of the white arrow toward the front side in the mounting direction with respect to the document conveying device 10, the image reading unit 80 eventually becomes. The protrusion 84b (second inclined portion 84b3) comes into contact with the contact member 90 (second engagement portion 90d).
Then, as shown in FIG. 7C, when the image reading unit 80 is further moved in the direction of the white arrow toward the front side in the mounting direction, the second engagement is performed along the second inclined portion 84b3 of the protruding portion 84b. The joining portion 90d moves relatively smoothly, and the top portion 84b1 of the protruding portion 84b gets on the transport surface 90a of the contact member 90 relatively. At this time, since the protruding portion 84b is hardly displaced in the vertical direction, the contact member 90 is moved downward (in the black arrow direction) so as to resist the urging force of the compression spring 91 by contact with the protruding portion 84b. It will be pushed. That is, the contact member 90 (the abutting portion 90 b) is in a state of being separated from the image reading surface 83 a of the image reading unit 80.
As a result of the contact with the protrusion 84b, the image reading unit 80 is completely separated from the document conveying device 10 while the contact member 90 is pushed downward.
Note that immediately before the separation of the image reading unit 80 from the document conveying device 10 is completed, an operation opposite to the operation of FIGS. 8A and 8B described later is performed, and the first inclined portion 84b is inclined. The first engaging portion 90c moves relatively smoothly along the portion 84b2, and the contact member 90 in the separated state moves smoothly upward.

On the other hand, when the image reading unit 80 detached from the document conveying device 10 is attached to the document conveying device 10, the image reading unit 80 and the contact member 90 are moved as shown in FIGS. Will work.
Specifically, as shown in FIG. 8A, first, when the image reading unit 80 is detached from the document conveying device 10, the protrusion 84b of the image reading unit 80 contacts the contact member 90. It is not in a state. At this time, the contact member 90 is displaced to the maximum (in the direction of the black arrow) by the urging force of the compression spring 91, and is conveyed upward by a distance Z from the image reading surface 83a of the image reading unit 80. The surface 90a is located.

On the other hand, when the image reading unit 80 is moved in the direction of the white arrow toward the back side in the mounting direction with respect to the document conveying device 10, the protrusion 84b (first inclined portion 84b2) of the image reading unit 80 is eventually found. However, it will be in the state which contacted the contact member 90 (1st engaging part 90c).
Then, as shown in FIG. 8B, when the image reading unit 80 is further moved in the direction of the white arrow toward the back side in the mounting direction, the first engagement is made along the first inclined portion 84b2 of the protruding portion 84b. The joining portion 90c moves relatively smoothly, and the top portion 84b1 of the protruding portion 84b gets on the conveyance surface 90a of the contact member 90 relatively. At this time, since the protruding portion 84b is hardly displaced in the vertical direction, the contact member 90 is moved downward (in the black arrow direction) so as to resist the urging force of the compression spring 91 by contact with the protruding portion 84b. It will be pushed. That is, the contact member 90 (the abutting portion 90 b) is in a state of being separated from the image reading surface 83 a of the image reading unit 80.
Thus, the contact with the protrusion 84b completes the mounting of the image reading unit 80 to the document feeder 10 while the contact member 90 is pushed downward.
Immediately before the mounting of the image reading unit 80 to the document feeder 10 is completed, an operation opposite to the operation described above with reference to FIGS. The second engagement portion 90d moves relatively smoothly along the second inclined portion 84b3, and the contact member 90 (abutting portion 90b) in the separated state smoothly contacts the image reading surface 83a. .

As described above, the image reading unit 83 is attached to and detached from the document conveying apparatus 10 with the contact member 90 being pushed downward, so that the image reading surface 83a contacts the image reading unit 80 when the image reading unit 80 is attached or detached. It is possible to reliably reduce problems such as sliding contact with the member 90 and deteriorating detachment operability and scratches on the image reading surface 83a. In particular, in the present embodiment, by providing the protruding portion 84 b on a part of the housing 84 of the image reading unit 80, such an effect can be obtained without increasing the size and cost of the document conveying device 10. It will be possible.
The protrusion 84b of the image reading unit 80 is formed only on one end in the width direction. Therefore, when the image reading unit 80 is attached / detached, the contact member 90 is uniformly downward in the width direction with a good balance. Although it is unlikely to be pushed, the abutting force of the abutting member 90 on the image reading surface 83a is reliably reduced, so that the above-described effects are exhibited.

Here, as described above, in the contact member 90 in the present embodiment, the first engaging portion 90c and the second engaging portion 90d are each formed in an R shape. As a result, when the engaging portions 90c and 90d are engaged along the inclined surfaces of the inclined portions 84b2 and 84b3 of the protruding portion 84 in the image reading unit 80, a smooth contact is generated without causing a catching impact. The member 90 is pushed.
In the present embodiment, the first engagement portion 90c and the second engagement portion 90d are formed in an R shape, but the first engagement portion 90c and the second engagement portion 90d are inclined (for example, In the case of forming the first engaging portion 90c and the second engaging portion 90d as inclined surfaces that are inclined with respect to the conveying surface 90a, the above-mentioned is also used. In substantially the same manner, the contact member 90 can be smoothly pushed without causing a catching impact.
Furthermore, even when the surfaces of the inclined portions 84b2 and 84b3 and the surfaces of the engaging portions 90c and 90d are formed of a low friction material by coating or the like, there is no impact that can be caught in the same manner as described above. Further, the frictional resistance is further reduced, and the contact member 90 can be pushed smoothly.

Further, in the present embodiment, referring to FIG. 7 and the like, corners are formed at the apex portion 84b1 of the protrusion 84b at the boundary with the first inclined portion 84b2 and the boundary with the second inclined portion 84b3, respectively. In order to prevent this, it is formed in a curved shape over the attaching / detaching direction (width direction). As a result, the image reading unit 80 is moved in the attaching / detaching direction in a state in which the protruding portion 84b rides on the conveyance surface 90a of the contact member 90 (the state shown in FIGS. 7C and 8B). In addition, the contact area (friction resistance) between the protrusion 84b and the conveyance surface 90a is reduced, and the image reading unit 80 is smoothly moved.
Even when the surface of the top portion 84b1 of the protruding portion 84b is formed of a low friction material by coating or the like, the frictional resistance between the protruding portion 84b and the conveying surface 90a is reduced, so that the image reading unit 80 is smooth. Will be moved.

As described above, the image reading unit 80 has a boss portion 84 a for engaging with the main body side plate 102 (rear side plate) of the apparatus and positioning the document conveying apparatus 10 on the back side in the mounting direction. It is formed so as to protrude toward the back in the mounting direction (see also FIG. 9).
As shown in FIG. 10, in the present embodiment, the protrusion for pushing the contact member 90 may be a part of the boss portion 84 a. Specifically, as shown in FIG. 10, the tip of the boss portion 84a (the end on the back side in the mounting direction) is formed in a taper shape, and the lower end of the taper is the first inclined portion of the protrusion. 84a1 and is configured to function in the same manner as the first inclined portion 84b2 of the protruding portion 84b of FIG. Further, a portion from the bottom of the boss portion 84a to a part of the bottom of the housing 84 becomes a top portion 84c, and is configured to function in the same manner as the top portion 84b1 of the protruding portion 84b of FIG. Furthermore, a part of the bottom portion of the housing 84 becomes the second inclined portion 84d, and is configured to function similarly to the second inclined portion 84b3 of the protruding portion 84b of FIG.
Even in such a case, as in the case of FIG. 7, when the image reading unit 80 is attached / detached, the image reading surface 83a is in sliding contact with the contact member 90 and the attachment / detachment operability is deteriorated. Problems such as scratches on the reading surface 83a can be reliably reduced. In particular, in the examples of FIGS. 9 and 10, a part of the positioning boss portion 84 a functions as a protruding portion that pushes the contact member 90, so that the image reading unit 80 is further downsized. Will be.

As described above, in the present embodiment, the image reading unit 80 that is attached to and detached from the document conveying device 10 in the width direction is located on the back side in the mounting direction with respect to the image reading surface 83a. Projecting toward the abutting member 90 and against the urging force of the compression spring 91 (the urging member) by abutting against the abutting member 90 in conjunction with the attaching / detaching operation with respect to the document conveying device 10. A protrusion 84b that pushes the contact member 90 is provided.
Accordingly, the abutting member 90 is separated from the image reading surface 83a of the image reading unit 80 in conjunction with the operation of attaching / detaching the image reading unit 80 to / from the document conveying apparatus 10 with a relatively simple configuration. be able to.

In the present embodiment, the present invention is applied to the document conveying device 10 installed in the monochrome image forming apparatus 1. However, the document conveying device installed in the color image forming apparatus is naturally also applied. The present invention can be applied.
In the present embodiment, the present invention is applied to the document conveying device 10 installed in the electrophotographic image forming apparatus 1. However, the application of the present invention is not limited to this, and other methods are used. The present invention can also be applied to a document conveying device installed in an image forming apparatus (for example, an inkjet image forming apparatus or a stencil printing machine).
Even in these cases, the same effects as those of the present embodiment can be obtained.

In the present embodiment, the contact member 90 does not have to be a plate-shaped guide plate (plate-shaped member). For example, a roller-shaped member disclosed in Patent Document 1 is used as the contact member. You can also.
Further, in the above-described embodiment, the present invention is applied to one image reading unit 80 (second image reading unit) for the document conveying apparatus 10 in which the plurality of image reading units 2 and 80 are installed. The first image reading unit 2 and a single image reading unit (an image reading unit for the front side) are also included in the present embodiment. Of course, the present invention can be applied as long as it is unitized.

  It should be noted that the present invention is not limited to the present embodiment, and it is obvious that the present embodiment can be modified as appropriate within the scope of the technical idea of the present invention, other than suggested in the present embodiment. is there. In addition, the number, position, shape, and the like of the constituent members are not limited to the present embodiment, and the number, position, shape, and the like suitable for implementing the present invention can be achieved.

  In the present application, “original” is defined to include all originals made of sheet-like members such as OHP in addition to paper originals.

1 image forming apparatus (image forming apparatus main body),
2 first image reading unit,
10 Document transport device (automatic document transport / image reading device),
61 Document placement section (document table),
62 Document discharge section,
80 image reading unit (second image reading unit),
81 faceplate,
82 CIS (main part of image reading unit),
83 Contact glass,
83a Image reading surface (original transport surface),
84 housing,
84a boss part,
84a1 second inclined portion,
84b protrusion,
84b1 top part, 84b2 first inclined part, 84b3 second inclined part,
84c top part, 84d first inclined part,
85 cover,
90 Contact member (plate-like member, guide plate),
90a conveying surface,
90b Abutment part,
90c first engaging portion, 90d second engaging portion,
91 compression spring (biasing member),
101 Main body side plate (front side plate),
102 Main body side plate (rear side plate),
120 screws, D manuscript.

JP 2009-225041 A

Claims (7)

A document transport device that transports a document,
An image reading unit that is detachably installed in the apparatus with the width direction orthogonal to the document transport direction as the attachment / detachment direction, and reads the image information of the document;
A contact member that is urged by the urging member to contact the image reading surface of the image reading unit;
With
The image reading unit protrudes toward the contact member with respect to the image reading surface at a position on the back side in the mounting direction with respect to the image reading surface, and in conjunction with an attaching / detaching operation with respect to the device. An original conveying apparatus comprising: a protrusion that pushes the abutting member so as to abut against the abutting member and resist the urging force of the urging member.   The protruding portion is inclined from the top portion toward the back side in the mounting direction so as to be separated from the contact member, and from the contact member toward the front side in the mounting direction from the top portion. The document conveying device according to claim 1, further comprising a second inclined portion that is inclined so as to be separated.   The protrusion is characterized in that the top portion is formed in a curved shape in the attaching / detaching direction so that corner portions are not formed at the boundary between the first inclined portion and the boundary between the second inclined portion, respectively. The document feeder according to claim 2. The contact member is formed with a first engagement portion that engages with the first inclined portion of the projection portion at a position on the near side in the mounting direction, and the projection portion at a position on the back side in the mounting direction. A second engaging portion that engages with the second inclined portion is formed,
4. The document conveying device according to claim 2, wherein the first engagement portion and the second engagement portion are formed in an R shape or a slope shape, respectively. 5. The image reading unit is formed on the back side in the mounting direction so that a boss portion for engaging with a main body side plate of the device to perform positioning with respect to the device protrudes toward the back side in the mounting direction.
The document feeder according to claim 1, wherein the protrusion is a part of the boss. The image reading surface is a surface of a member formed of a light transmitting material,
The said abutting member is a plate-shaped member provided with the conveyance surface extended in the said width direction so as to oppose the said image reading surface, The Claim 1 characterized by the above-mentioned. Document transport device.   An image forming apparatus comprising the document conveying device according to claim 1.

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