JP5252294B2 - Document feeder - Google Patents

Description

  The present invention relates to a document conveying device including a conveying roller for conveying a document.

  When a document is transported using the document transport device, static electricity is generated due to friction between the transported document and members constituting the document transport path. As a technique for removing such static electricity, a technique is known in which a grounded grounding conductive member is brought into contact with the rotating shaft of the transport roller, and the static electricity is discharged to the outside of the apparatus through the grounding conductive member. (For example, Patent Document 1 below). In the example of Patent Document 1, the grounding conductive member (press spring) has one end fixed and the other end constituting a pressing portion that presses the rotation shaft of the transport roller.

Japanese Patent Laid-Open No. 2001-233489

  For example, when the rotating shafts of a plurality of transport rollers are brought into contact with one earth conductive member and grounded, the ground conductive member is different from the configuration disclosed in Patent Document 1 described above. The structure which supports in a support part may be employ | adopted. In such a configuration, the grounding conductive member may be brought into contact with the rotating shaft of the transport roller between the at least two support portions.

  In such a case, a pressing member for pressing the rotating shaft of the conveying roller is separately provided, and the rotating shaft of the conveying roller moved against the pressing force of the pressing member contacts the grounding conductive member. It is conceivable to adopt such a configuration. However, in such a configuration, the grounding conductive member supported by the at least two support portions interferes with the rotating shaft that moves against the pressing force of the pressing member, and the pressing force of the conveying roller against the document varies. May occur.

  The present invention has been made in view of the above circumstances, and provides a document conveying device that can satisfactorily ground the rotation shaft of the conveying roller and stabilize the pressing force of the conveying roller against the document. With the goal.

  A document conveying device according to a first aspect of the present invention is a document conveying device including a conveying roller for conveying an original, and the rotation axis of the conveying roller is along a moving direction orthogonal to the rotation axis. A holding member that is movably held, a grounding portion that is provided on the holding member and is grounded, a grounding conductive member that is provided so as to contact the rotating shaft and the grounding portion, and the grounding conductive member At least two supporting portions for supporting the grounding member, and the grounding conductive member is formed with a swinging piece swingable along the moving direction, and the swinging piece is supported by the at least two supporting parts. The rotating shaft is in contact between the portions.

  According to such a configuration, the grounding conductive member supported by the at least two support portions is transported between the at least two support portions via the swinging piece formed on the grounding conductive member. Can be brought into contact with the rotating shaft. In this way, the contact portion of the grounding conductive member that hinders the rotation axis of the transport roller moving along the moving direction is a swing piece that can swing with respect to the pressing force of the rotation shaft. Thus, it is possible to prevent a desired pressing force on the document from being obtained (the pressing force is insufficient) when the number of the conveying rollers is one, and variation occurs in the pressing force on the document when there are a plurality of conveying rollers. Can be prevented. As a result, the rotation shaft of the conveyance roller can be satisfactorily grounded, and the pressing force of the conveyance roller against the document can be stabilized.

  A document conveying apparatus according to a second aspect of the present invention includes a pressing member that presses the rotating shaft along the moving direction, the direction in which the pressing member presses the rotating shaft, and the swing piece is the rotating shaft. The pressing force of the pressing member against the rotating shaft is greater than the pressing force of the swinging piece against the rotating shaft.

  According to such a configuration, it is possible to apply a pressing force of the conveying roller to the document by pressing the rotation shaft of the conveying roller with the pressing member. In particular, since the pressing force of the pressing member on the rotating shaft is larger than the pressing force of the swinging piece on the rotating shaft, it is effective that the pressing force of the swinging piece causes a shortage or variation in the pressing force of the conveying roller against the document. Can be prevented.

  In the document conveying device according to a third aspect of the present invention, the grounding conductive member has an elongated shape extending in a direction perpendicular to the rotation axis, and the at least two support portions include the grounding conductive member. And a concave portion is formed for preventing the earth conductive member from moving in the short direction.

  According to such a configuration, it is possible to prevent the ground conductive member from moving in the lateral direction by housing the ground conductive member in the recess. When the grounding conductive member has a long shape extending in a direction orthogonal to the rotation axis of the transport roller, the grounding conductive member is grounded in the short direction of the grounding conductive member, that is, in the direction parallel to the rotation shaft. The conductive member is easily displaced. Therefore, as in the present invention, by providing a recess for preventing the earth conductive member from moving in the short direction, it is possible to prevent the earth conductive member from being displaced with a simple configuration, and to transport the swing piece and the swing piece. The rotating shaft of the roller can be reliably brought into contact.

  According to the present invention, the contact portion of the grounding conductive member that hinders the rotation shaft of the transport roller that moves along the moving direction is provided with the swing piece that can swing with respect to the pressing force of the rotation shaft. As a result, the rotation shaft of the transport roller can be satisfactorily grounded, and the pressing force of the transport roller against the document can be stabilized.

1 is a perspective view illustrating an external configuration of an image forming apparatus including a document conveying device according to an embodiment of the present invention. It is the perspective view which showed the internal structure of the holding member, and has abbreviate | omitted and shown the cover member which opposes a main body in the closed state. It is the perspective view which showed the external appearance structure of the electrically-conductive member for earth | grounds.

  FIG. 1 is a perspective view showing an external configuration of an image forming apparatus including a document conveying device 1 according to an embodiment of the present invention. In the following description, the left back side in FIG. 1 will be described as left, the right front side as right, the left front side as front, and the right back side as back.

  The image forming apparatus includes, for example, a copying function capable of reading an image of a document automatically supplied one by one by the document conveying device 1 and forming an image on recording paper based on the image data of the document. In addition to the copying function, it is equipped with a scanner function and a facsimile function. However, the document conveying device 1 according to the present invention is not limited to a multi-function device, and can be applied to other image forming devices such as a copying machine or a facsimile device, or various devices such as a scanner device that does not include an image forming unit. is there.

  This image forming apparatus includes a document reading unit and an image forming unit (both not shown) in a housing 2, and a document transport device 1 is provided on the top surface of the housing 2. The document conveying device 1 includes a main body 3 provided on the upper surface of the housing 2 and a holding member 4 that is attached to the main body 3 so as to be openable and closable and holds various rollers. FIG. 1 shows a state in which the holding member 4 is opened with respect to the main body 3. The configurations of the document reading unit and the image forming unit are well known, and thus detailed description thereof is omitted here.

  The main body 3 of the document conveying device 1 is provided with a document tray 5 for setting a document, and the documents set on the document tray 5 are sent out one by one to the document conveying path 6. When the holding member 4 is closed, the holding member 4 and the main body 3 face each other with a space therebetween, and the space constitutes the document conveyance path 6. In the holding member 4, a pickup roller 7, a paper feed roller 8, and transport rollers (driven rollers) 9, 10 are respectively rotating shafts (not shown) that extend in parallel with each other along the front-rear direction (axial direction of each roller). Is held rotatably around the center.

  The pickup roller 7 is a roller for sending out the originals set on the original tray 5 one by one. In this example, two pickup rollers 7 are held so as to be rotatable about the same rotation axis. However, the number of the pickup rollers 7 is not limited to two, and may be a configuration in which only one pickup roller 7 is provided, or three or more pickup rollers 7 may be provided.

  The paper feed roller 8 is disposed in the vicinity of the pickup roller 7 and conveys the document sent out by the pickup roller 7 to the downstream side. In this example, one paper feed roller 8 is held so as to be rotatable about a rotation axis. However, the number of paper feed rollers 8 is not limited to one, and a plurality of paper feed rollers 8 may be provided.

  In the main body 3, a separation member (retard roller) (not shown) is rotatably provided at a position where the holding member 4 is in contact with the paper feed roller 8 in a closed state. As a result, when two or more originals are double-fed by the pickup roller 7, only one original is conveyed by the action of the paper feed roller 8 and the separating member.

  A plurality of transport rollers 9 and 10 are arranged downstream of the paper feed roller 8 in the document transport direction. These conveying rollers 9 and 10 constitute a conveying roller pair together with a driving roller (not shown) provided at an opposing position on the main body 3 side, and each conveying roller pair is driven by the driving of the driving roller. The image of the document conveyed by the above is read by the document reading unit in the housing 2 at a reading position located in the middle of the document conveying path 6. An image is formed on the recording paper by the image forming unit based on the image data of the document read by the document reading unit. The document after the image is read is discharged onto a discharge tray 11 formed on the upper surface of the main body 3 located below the document tray 5.

  In the present embodiment, the holding member 4 is rotatably attached to the main body 3. Specifically, the holding member 4 is rotatable around a rotation axis set to extend in the front-rear direction at the left end portion of the main body 3. The holding member 4 holds the lock claws 12 at the front end portion and the rear end portion at the position which becomes the right end portion in the closed state. The main body 3 is provided with lock pins 13 that are hooked on the respective lock claws 12 at positions corresponding to the respective lock claws 12 in a state where the holding member 4 is closed.

  The holding member 4 is provided with an operation lever 14 that is operated to unlock the lock claw 12 with respect to the lock pin 13 at a position that is the right end portion in the closed state. The operation lever 14 is provided so as to be rotatable around a rotation axis extending in the front-rear direction. By rotating the operation lever 14 upward with the holding member 4 closed, the lock claw 12 is rotated, The lock on the lock pin 13 can be released. The lock claw 12, the lock pin 13, and the operation lever 14 as described above constitute a lock mechanism 20 for locking the holding member 4 in the closed state.

  However, the lock mechanism 20 is not limited to the configuration in which the two lock claws 12 are provided, and may have a configuration in which only one lock claw 12 is provided. In addition, the lock mechanism 20 is not limited to the configuration in which the holding member 4 is locked using the lock claw 12, and other various configurations may be adopted as long as the holding member 4 can be locked in the closed state. Can do.

  FIG. 2 is a perspective view showing the internal configuration of the holding member 4, and the cover member facing the main body 3 in a closed state is omitted.

  As shown in FIG. 2, the two pickup rollers 7 are attached to the same pickup roller rotating shaft 71 that is rotatably held by the holding member 4. The paper feed roller 8 is attached to the paper feed roller rotating shaft 81 so that the position in the front-rear direction (the axial direction of the paper feed roller 8) is between the two pickup rollers 7. Both ends of the pickup roller rotating shaft 71 are connected to the sheet feeding roller rotating shaft 81 via connecting members 82.

  A driven gear 83 is attached to one end portion of the rotation shaft 81 for the feed roller, and the driven gear 83 is connected to a drive gear (not shown) provided in the main body 3 with the holding member 4 closed. It has come to be. The driving gear is connected to a driving device such as a motor provided in the main body 3, and the connecting member 82 conveys the document by a mechanism (not shown) by the driving force from the driving device transmitted to the driven gear 83. Depending on the situation, the sheet feeding roller rotating shaft 81 is moved up and down as the rotating shaft, and the sheet feeding roller rotating shaft 81 and the sheet feeding roller 8 attached to the sheet feeding roller rotating shaft 81 are rotated. Yes.

  The pickup roller rotary shaft 71 and the paper feed roller rotary shaft 81 are connected via a belt 84 wound around a pulley attached thereto. As a result, when the driving force from the driving device is transmitted to the driven gear 83, the belt 84 and the pickup roller rotating shaft 71 connected to the belt 84 as the paper feeding roller rotating shaft 81 rotates. And the pickup roller 7 and the paper feed roller 8 are rotated in synchronization. The pickup roller 7, the paper feed roller 8, the pickup roller rotary shaft 71, the paper feed roller rotary shaft 81, the connecting member 82, the driven gear 83, the belt 84, and the like send out the documents set on the document tray 5 one by one. Constitutes the document sending section for

  The lock mechanism 20 includes a lock rotating shaft 15 connected to the operation lever 14 in addition to the lock claw 12, the lock pin 13, and the operation lever 14 described above. The lock rotation shaft 15 is rotatably attached to the holding member 4 so as to extend along the front-rear direction (a direction parallel to the pickup roller rotation shaft 71 and the paper feed roller rotation shaft 81). It rotates based on the operation of the operation lever 14. In the present embodiment, the lock rotating shaft 15 is disposed between the pickup roller rotating shaft 71 and the paper feed roller rotating shaft 81 in a plan view, that is, at a position overlapping the connecting member 82 in a plan view.

  A plurality of transport rollers 9 are provided, and each is mounted on the same transport roller rotation shaft 91. In this example, three conveyance rollers 9 are attached to a rotation shaft 91 for conveyance rollers that cannot be rotated so as to be spaced apart from each other. The conveyance roller rotation shaft 91 is a direction orthogonal to the conveyance roller rotation shaft 91 and a direction orthogonal to the document conveyance direction, that is, the vertical direction in the present embodiment (in this embodiment). The vertical direction of the image forming apparatus is a movement direction, and is held by the holding member 4 in a movable state along the movement direction.

  The conveyance roller rotating shaft 91 is pressed downward (vertically downward in the image forming apparatus according to the present embodiment) along the moving direction by a compression spring 92 which is an example of a pressing member. The main body 3 of the document conveying apparatus 1 is provided with drive rollers (not shown) that abut on the respective conveying rollers 9 with the holding member 4 closed, and each conveying roller 9 is acted upon by the action of the compression spring 92. Contact with the drive roller so as to generate a predetermined nip pressure. The nip pressure here is a conveying roller constituted by the driving roller corresponding to each conveying roller 9 by the pressing force of each conveying roller 9 against the driving roller and the repulsive force of the driving roller against each conveying roller 9. It means the pressure at the time of sandwiching the originals generated in pairs. In this example, the compression springs 92 having the same characteristics are arranged between the adjacent conveyance rollers 9, so that the nip pressures of the respective conveyance roller pairs are set to be uniform. The pressing member is not limited to the compression spring 92, and various members such as an elastic body such as rubber can be used.

  The holding member 4 is provided with a ground portion 16 made of a conductive plate such as a metal plate. A ground wire 17 is connected to the ground portion 16, and the ground portion 16 is grounded via the ground wire 17. When a document is transported using the document transport device 1, static electricity is generated due to friction between the transported document and members (in this example, the main body 3 and the holding member 4) constituting the document transport path 6. . In order to remove such static electricity, in the present embodiment, various parts held by the holding member 4 are connected to the ground portion 16 via the grounding conductive member 18, and the grounding conductive member 18 is used to connect the various parts. Static electricity is discharged to the outside of the device.

  In the present embodiment, the grounding conductive member 18 is directly or indirectly connected to the rotation shafts of the paper feed roller 8 and the transport rollers 9 and 10. As long as the grounding conductive member 18 is formed of a conductive material, the grounding conductive member 18 may be formed of a metal such as stainless steel or may be formed of a conductive resin. May be.

  FIG. 3 is a perspective view showing the external configuration of the grounding conductive member 18. The grounding conductive member 18 is formed of a metal plate, and has a long shape extending in a direction perpendicular to the respective rotation axes of the pickup roller 7, the paper feed roller 8, and the transport rollers 9 and 10.

  A swing piece 181 for making contact with the rotation shaft 91 for the transport roller is formed at the center in the longitudinal direction of the grounding conductive member 18. The swing piece 181 has a long shape extending in a direction orthogonal to the rotation axis 91 for the transport roller, and one end portion in the longitudinal direction is cantilevered so that the other end portion is in the vertical direction, that is, A free end that can swing along the moving direction of the rotation shaft 91 for the transport roller is configured.

  The holding member 4 is formed with a recess 19 as a support portion for supporting the ground conductive member 18 on the upstream side and the downstream side in the document transport direction with respect to the transport roller rotation shaft 91. The grounding conductive member 18 is supported in a state of being accommodated in the recesses 19, and the grounding conductive member 18 moves in the short direction, that is, the direction in which the rotation shaft 91 for the transport roller extends by the recesses 19. Can be prevented. The swing piece 181 of the grounding conductive member 18 is in contact with the conveyance roller rotating shaft 91 between the two recesses 19 at the end of the free end thereof.

  However, the grounding conductive member 18 is not limited to a configuration that is supported by the concave portion 19, and may be configured to be supported by another support portion including a flat surface or a convex portion. The ground conductive member 18 is not limited to be supported by two support portions, and may be configured to be supported by three or more support portions. In this case, if the swing piece 181 of the grounding conductive member 18 is configured to come into contact with the transport roller rotation shaft 91 between any two adjacent support portions, the swing piece 181 contacts between any support portions. Such a configuration may be adopted.

  One end of the grounding conductive member 18 in the longitudinal direction is in contact with a rotation shaft (not shown) of the transport roller 10. A curved portion 182 that is curved in an arc shape is formed at the other end portion of the grounding conductive member 18 in the longitudinal direction, and the curved portion 182 is rotatably attached to the rotation shaft 81 for the feed roller. It is attached to the outer peripheral surface of the bearing 85. The curved portion 182 is formed with a slit 183 for inserting the protrusion 86 formed on the outer peripheral surface of the bearing 85 and fixing the grounding conductive member 18.

  A through hole 184 is formed in the grounding conductive member 18 between the swing piece 181 and the curved portion 182, that is, between the contact portions of the transport roller rotating shaft 91 and the feed roller rotating shaft 81. ing. The periphery of the through hole 184 of the grounding conductive member 18 constitutes a contact portion with the ground portion 16, and a screw hole 185 is formed in the ground portion 16 by inserting a screw 185 through the through hole 184. The grounding conductive member 18 can be fixed to the ground portion 16 by tightening to the grounding portion (not shown).

  In the present embodiment, the grounding conductive member 18 supported by the two concave portions 19 is rotated between the two concave portions 19 via the swing piece 181 formed on the grounding conductive member 18. The shaft 91 can be contacted. In this way, the contact portion of the grounding conductive member 18 that hinders the transport roller rotating shaft 91 moving in the moving direction (vertical direction) is shaken against the pressing force of the transport roller rotating shaft 91. By using the movable swing piece 181, it is possible to prevent the pressing force of the conveying roller 9 against the document and the corresponding driving roller from being insufficient or uneven. Thereby, the rotation shaft 91 for the conveyance roller can be satisfactorily grounded, and the pressing force of the conveyance roller 9 against the document and the corresponding drive roller can be stabilized. As a result, the nip pressure on the document by the driving roller corresponding to the conveying roller 9 is also stabilized.

  In the present embodiment, the direction in which the compression spring 92 presses the conveyance roller rotation shaft 91 and the direction in which the swing piece 181 presses the conveyance roller rotation shaft 91 coincide with each other. Further, the pressing force of the compression spring 92 against the transport roller rotation shaft 91 is set to be larger than the pressing force of the swing piece 181 against the transport roller rotation shaft 91. Thereby, it is possible to effectively prevent the pressing force of the conveying roller 9 from being applied to the document and the corresponding driving roller due to the pressing force of the swing piece 181.

  Further, in the present embodiment, by housing the grounding conductive member 18 in the recess 19, it is possible to prevent the grounding conductive member 18 from moving in the short direction. When the grounding conductive member 18 has a long shape extending in a direction orthogonal to the transport roller rotating shaft 91 as in the present embodiment, the grounding conductive member 18 is short, that is, transported. The grounding conductive member 18 is likely to be displaced in a direction parallel to the roller rotation shaft 91. Therefore, as in the present embodiment, by providing the concave portion 19 for preventing the ground conductive member 18 from moving in the short direction, the ground conductive member 18 is prevented from being displaced with a simple configuration. The moving piece 181 and the conveyance roller rotating shaft 91 can be reliably brought into contact with each other.

DESCRIPTION OF SYMBOLS 1 Original conveyance apparatus 3 Main body 4 Holding member 6 Original conveyance path 7 Pickup roller 8 Paper feed roller 9 Conveyance roller 10 Conveyance roller 16 Ground part 17 Ground wire 18 Grounding conductive member 19 Concave part 71 Pickup roller rotating shaft 81 Feed roller Rotating shaft 85 Bearing 86 Projection 91 Rotating shaft for conveying roller 181 Swing piece 182 Bending portion 183 Slit 184 Through hole

Claims (3)

An original conveying apparatus provided with an conveying roller for conveying an original,
A holding member that holds the rotation axis of the transport roller movably along a moving direction orthogonal to the rotation axis;
A grounding portion provided on the holding member and grounded;
A grounding conductive member provided in contact with the rotating shaft and the ground portion;
And at least two support parts for supporting the grounding conductive member,
The grounding conductive member is formed with a swing piece that can swing along the moving direction, and the swing piece is in contact with the rotating shaft between the at least two support portions. An original conveying apparatus characterized by the above. A pressing member that presses the rotating shaft along the moving direction;
The direction in which the pressing member presses the rotating shaft and the direction in which the swing piece presses the rotating shaft are the same,
The document conveying apparatus according to claim 1, wherein a pressing force of the pressing member against the rotating shaft is larger than a pressing force of the swinging piece against the rotating shaft. The grounding conductive member has a long shape extending in a direction perpendicular to the rotation axis,
The at least two support portions are supported in a state in which the grounding conductive member is accommodated, and a recess is formed to prevent the grounding conductive member from moving in the short direction. The document conveying apparatus according to claim 1 or 2.

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