JP2008024485A - Document feeder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a document feeder the inside of which is efficiently cooled by a fan, which is effectively increased in document feeding performance, and remarkably enhanced in the stability of document feeding. <P>SOLUTION: The fan 34 fitted to the document feeding part 10 of a document feeder 1 is so installed that air flows in a document feeding path 13 on the upstream side of the fan 34 from the upstream side to the downstream side in the document feeding direction. Since the air flow by the fan 34 flows along the flow of the document feeding, a document D can be fed without applying a brake. The document feeder comprises an air direction changing mechanism 40 for changing over the direction of the air by the fan 34 from the direction of the end surface of a document loading tray 2 on the downstream side of a document bundle Dm to the direction of a document discharge port 17 for discharging the document D to a document discharge tray 3. Consequently, the air can be effectively applied to the end surface of the document bundle Dm, and the document D can be positively pushed out to the document discharge tray 3 through the document discharge port 17. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a document conveying apparatus applicable to an image forming apparatus represented by a copying machine or a facsimile.

  Some image forming apparatuses such as copiers and facsimiles include a document transport device that automatically sends a plurality of documents to a document reading unit. The document conveying device separates and conveys one sheet at a time from the uppermost layer of the bundle of documents stacked on the document placing tray. The original is read by the original reading unit, and then discharged onto a document discharge tray provided on the most downstream side of the original conveyance path.

  A supply member such as a supply roller or a supply belt is used to transfer the document from the document placement tray to the document transport path continuing to the document reading unit. The supply member is provided at the downstream side of the document placing tray in the document transport direction, and presses the uppermost layer of the document bundle to send the document downstream. On the document conveyance path, conveyance rollers and rollers for conveying the document are provided at various locations, and the document is inserted and conveyed through a nip formed by the pressure-contact between these conveyance rollers and the roller. .

  In the document conveying device having the above-described configuration, the image data on the surface is read when the document contacts or approaches the document reading device at the position of the document reading unit. However, at this time, there is a concern that the original document sticks to the glass portion on the surface of the original reading device and is difficult to be separated, and the conveyance performance is lowered. Therefore, in order to solve such a problem, a structure for improving the separation property of the document on the surface of the document reading apparatus has been proposed. In the document feeding device (document conveying device) described in Patent Document 1, an air flow from a fan is blown from the downstream side in the document conveying direction toward the platen glass at the reading position of the document reading device.

On the other hand, separation means using an air flow has been proposed in order to separate the originals stacked on the original placement tray one by one in the original conveying apparatus. In this method, air is blown from the lateral direction to the downstream end surface of the document bundle in the conveying direction to lift and separate the upper layer document. Patent Documents 2 and 3 show examples of document conveying devices that facilitate separation of documents stacked in this way.
Japanese Patent Laying-Open No. 2005-200352 (page 4, FIG. 1) Japanese Patent No. 2947855 (second page, FIG. 1) JP-A-9-165144 (5th page, FIG. 1)

  The document feeding device (document transporting device) described in Patent Document 1 uses an air flow at a reading position of the document reading device to improve separation of the document from the platen glass. In terms of preventing sticking to the sheet, it is possible to improve the conveyance performance. However, since the air is blown from the downstream side in the document transport direction in the document reading unit, the document is transported in the form of a brake, and it is difficult to say that the document transport performance is effectively improved. .

  In addition, the automatic document feeder described in Patent Document 2 and the automatic document feeder described in Patent Document 3 supply the document by blowing air against the bundle of documents stacked on the document placement tray. It is possible to improve the separation performance of the original and improve the supply performance. However, this air flow is used only to facilitate the separation of the original when the original is supplied, and is used to separate the original from the platen glass or to improve other conveyance performance. It is not done. Therefore, the configuration and power for generating the air flow are not efficiently used.

  On the other hand, the document conveying device may have a built-in motor for driving the conveying roller, its control board, and a document reading device for duplex printing. If the temperature inside the document conveying device is increased and the temperature rises, the image formed on the document surface, the control board, and the document reading device may be adversely affected and the document reading accuracy may be reduced. Therefore, it is necessary to efficiently cool the inside of the document conveying device.

  The present invention has been made in view of the above points, and in addition to efficiently cooling the inside of the apparatus with a fan, the document conveying performance can be effectively improved, and the stability of document conveying is greatly improved. An object of the present invention is to provide an improved document conveying apparatus.

  In order to solve the above-described problems, the present invention provides a fan for cooling the inside of a document transporting apparatus that separates and transports documents stacked on a document placing tray one by one so as to read image data on a document surface. The air flows through the document conveyance path on the upstream side of the fan and flows from the upstream side to the downstream side in the document conveyance direction, and the wind direction of the air discharged from the exhaust port of the fan is It is provided with a wind direction variable mechanism that switches from the downstream end face direction of the bundle of documents stacked on the document placement tray to the document discharge port direction for discharging the document to the document discharge tray provided on the most downstream side of the document transport path.

  In the document conveying apparatus having the above-described configuration, the wind direction varying mechanism changes the wind direction in accordance with the number of documents stacked on the document loading tray and / or the number of sheets supplied from the document loading tray.

  Further, in the document conveying device having the above-described configuration, the wind direction varying mechanism includes a sector gear attached to a lift member of the document stacking tray that moves up and down according to a change in the number of documents stacked, and a pinion that meshes with the sector gear. A rack that meshes with the pinion, a slide member that is attached to the rack and that slides along with the rotation of the pinion, and that the downstream portion in the air circulation direction is rotatably supported by the slide member, and a variable in which the wind direction changes as the slide member moves. It was decided to be equipped with a slat.

  Further, in the document conveying apparatus having the above-described configuration, the fan has its air inlet directed toward the document surface contacting the peripheral surface of the conveying roller provided upstream of the fan in the document conveying direction.

  In the document conveying apparatus having the above-described configuration, a plurality of the conveying rollers are provided in the document width direction perpendicular to the document conveying direction, and the fan circulates air between these two adjacent rollers. We decided to provide it.

  Further, in the document conveying device having the above-described configuration, the document placing tray and the document discharge tray are configured in two upper and lower stages with their document feeding directions reversed, and the document placing tray to the document. The document supply port for feeding the document and the document discharge port for discharging the document to the document discharge tray are provided on the same side of each tray, and the document conveyance path extending from the document supply port to the document discharge port is U-shaped in the vertical direction. It was supposed to be curved.

  According to the configuration of the present invention, in a document conveying device that separates and conveys the documents stacked on the document placing tray one by one so as to read the image data on the document surface, Since it is arranged in such a direction that it circulates in the document conveyance path on the upstream side of the fan and flows from the upstream side to the downstream side in the document conveyance direction, the air flow by the fan follows the flow of document conveyance, and the brake The document can be conveyed without applying the. Then, the document is pulled on the upstream side of the fan, and the conveyance of the document can be facilitated.

  Further, the direction of the air discharged from the exhaust port of the fan is discharged from the downstream end surface direction of the bundle of documents stacked on the document stacking tray to the document discharge tray provided on the most downstream side of the document transport path. Since it is equipped with a wind direction variable mechanism that switches to the direction of the document discharge port to be used, by changing the wind direction of the air flow by the fan, the air can be effectively blown to the end face of the document stack of the document discharge tray, Further, it is possible to positively push out the document from the document discharge port to the document discharge tray. As a result, the separation of the documents further proceeds in the document placing tray, and the supply performance can be improved. Then, it is possible to prevent a problem that the document discharged to the document discharge tray is stuck at the position of the document discharge port, caught by a discharge roller or the like provided in the vicinity thereof, and caught and damaged at an unintended position. is there. Therefore, the air flow generated by the fan can be used to enhance the document conveying performance, promote separation of the document when supplying the document, and prevent the document from being damaged at the document discharge port. . Thus, in addition to efficiently cooling the inside of the apparatus by the fan, it is possible to effectively improve the document conveying performance and to provide a document conveying device in which the stability of the document conveying is greatly improved. Is possible.

  In addition, since the wind direction changing mechanism changes the wind direction in accordance with the number of originals loaded on the original tray and / or the number of sheets supplied from the original tray, the air flow from the fan is changed as necessary. Thus, it can be sprayed from the proper direction onto the end face of the original bundle with the proper amount. Accordingly, it is possible to enhance the action of separating the original, and the supply performance at the time of supplying the original is improved.

  Further, the wind direction varying mechanism includes a fan-shaped gear attached to a lift member of a document placing tray that moves up and down according to a change in the number of stacked documents, a pinion that meshes with the fan-shaped gear, a rack that meshes with the pinion, and a rack that Because it is provided with a slide member attached and slidably moved with the rotation of the pinion, and a variable slat that is rotatably supported by the slide member in the downstream direction of the air flow direction and the wind direction changes with the movement of the slide member, With such a simple configuration, it is possible to automatically change the wind direction of the air flow by the fan in accordance with the number of documents loaded on the document loading tray and the number of sheets fed from the document loading tray. Accordingly, it becomes easy to blow an appropriate amount of air against the end face of the document bundle from an appropriate direction. Therefore, the action of separating the original is further enhanced, and the supply performance of the original is greatly improved.

  Further, since the fan has its intake port directed to the document surface contacting the peripheral surface of the conveyance roller provided upstream of the fan in the document conveyance direction, the document is stretched on the conveyance roller by the suction of the fan. It can be attached. As a result, the adhesion between the transport roller and the document increases, and the document can be transported by the transport roller without slipping. Therefore, it is possible to further improve the document conveyance performance.

  Further, a plurality of conveying rollers are provided in the document width direction perpendicular to the document conveying direction, and the fan is provided so as to circulate air between these two adjacent rollers. It is possible to apply an action of sticking the original to the conveyance roller at a location closer to the location where the contact is made. Thereby, the conveyance roller and the original can be further brought into close contact with each other, and the conveyance performance of the original can be improved.

  In addition, the document placement tray and the document discharge tray are configured in two upper and lower stages with the document transport direction opposite to each other, a document supply port for feeding the document from the document placement tray, and a document discharge tray The document discharge port for discharging the document is provided on the same side of each tray, and the document conveyance path extending from the document supply port to the document discharge port is curved in a U shape in the vertical direction. In such a compactly designed document conveying apparatus, in addition to efficiently cooling the inside of the apparatus with a fan, the document conveying performance can be effectively improved, and the stability of document conveying can be improved. It becomes possible to greatly increase.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  First, an outline of the structure of an original conveying apparatus according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic vertical sectional front view of a document conveying device. A solid arrow in the figure indicates a sheet conveyance path and a conveyance direction. The document conveying device according to the embodiment of the present invention is designed as a document conveying device mounted on the upper part of a copier, a facsimile, or a multifunction machine having a function of a copier or a facsimile as an image forming apparatus. Shall.

  As shown in FIG. 1, the document conveying device 1 includes a document placing tray 2, a document feeding unit 10, and a document discharge tray 3.

  The document placing tray 2 is provided on the upper part of the document conveying device 1. On the document placing tray 2, the documents can be placed from above and stacked. The document placing tray 2 is configured to be inclined from upstream to downstream in the document conveying direction, that is, from right to left in FIG.

  A lift member 4 is provided on the downstream side of the document tray 2 in the document transport direction. The lift member 4 is configured by a plate-like member having a shape along the placement surface of the document placement tray 2. The lift member 4 is provided so as to be rotatable in a vertical plane with the support shaft 4a provided at the upstream end as a center and the downstream end as a free end. The lift plate 4 is driven to rotate about a support shaft 4a by a motor (not shown) so that the downstream end of the original stacked on the original stacking tray 2 is always in contact with the supply roller 12 arranged above the original. And is biased upward.

  The document feeder 10 includes a document supply port 11 and a supply roller 12 at the downstream end of the document placement tray 2 in the document conveyance direction. The supply roller 12 separates and supplies the originals stacked on the original placement tray 2 one by one from the uppermost layer. A document transport path 13 extends toward the inside of the document feeder 10 on the downstream side of the document supply port 11.

  The tip of the document conveyance path 13 reaches the bottom surface of the document conveyance device 1, and a first document reading unit 14 is provided at this position. The document sent to the first document reading unit 14 is moving further on the document conveyance path 13 to the downstream side, that is, in the position of the first document reading unit 14 in FIG. 1 from the left to the right. In addition, image data on the first surface, which is the lower surface, is read by a document reading device (not shown, hereinafter referred to as a first document reading device) of the image forming apparatus main body provided below.

  A second document reading unit 15 is provided downstream of the first document reading unit 14 in the document conveyance path 13. When it is necessary to read image data on both sides of the document, the document sent to the second document reading unit 15 is further moved downstream on the document conveyance path 13, that is, at the position of the second document reading unit 15 in FIG. Is moved from the left side to the right side, the image data on the second surface, which is the upper surface, is read by the second document reading device 16 provided above.

  A document discharge port 17 is provided at the downstream end of the document transport path 13. The document whose image data has been read is discharged from the document discharge port 17 to the document discharge tray 3.

  The document discharge tray 3 is provided immediately below the document placement tray 2, and these trays are configured in two upper and lower stages. The document discharged to the document placing tray 3 can be taken out from the front side of the document conveying device 1 (see FIG. 7).

  The document placing tray 2 and the document discharge tray 3 are opposite to each other in the document transport direction, that is, in FIG. 1, the document placing tray 2 sends the document to the left, and the document discharge tray 3 sends the document to the right. It is configured to be sent out to Thus, the document supply port 11 and the document discharge port 17 are provided on the same side of each tray, that is, on the left side in FIG. The document conveyance path 13 extending from the document supply port 11 to the document discharge port 17 is provided in a shape curved in a U-shape in the vertical direction as shown in FIG.

  With the above configuration, the document conveying device 1 feeds the document placed on the document placing tray 2 into the document feeding unit 10, reads the image data by the document reading unit, and then discharges the document to the document discharge tray 3. .

  Next, the detailed configuration of the document feeder 10 of the document conveying device 1 will be described with reference to FIG. 2 in addition to FIG. FIG. 2 is a schematic vertical sectional front view showing the document feeding portion of the document conveying device. In FIG. 2, the solid line arrows indicate the document conveyance path and conveyance direction, and the white arrows indicate the air circulation path and distribution direction.

  As described above, the document feeder 10 includes the document supply port 11 and the supply roller 12 at the downstream end of the document tray 2 in the document transport direction (see FIG. 2). The supply roller 12 is provided at a substantially central portion in the document width direction perpendicular to the document conveyance direction (see FIG. 7), presses the uppermost layer of the document stack stacked on the document loading tray 2, and moves the document downstream. And send it out. The document transport path 13 extends obliquely downward on the downstream side of the document supply port 11.

  As shown in FIG. 2, a separation roller 18 a and a paper feed roller 18 b that are in pressure contact with each other are provided on the document conveyance path 13 immediately downstream of the document supply port 11. The separation roller 18a and the paper supply roller 18b separate the originals received from the supply roller 12 one by one and send them out toward the first original reading unit 14 on the downstream side.

  A registration roller pair 19 is provided downstream of the conveyance roller pair 18. The registration roller pair 19 is composed of a registration roller 19a and a roller 19b that are in pressure contact with each other, and after correcting the oblique feeding so that accurate reading can be performed with respect to the document going to the first document reading unit 14. Send it out.

  A relatively large-diameter conveying roller 20 is provided downstream of the registration roller pair 19. The document conveying path 13 is about half the circumference of the large-diameter conveying roller 20 and continues downstream along the circumferential surface. As a result, the document conveyance path 13 extends toward the left in FIG. 2 on the upstream side of the large-diameter conveyance roller 20, and extends toward the right on the downstream side. During this time, three rollers 21, 22, and 23 that are in pressure contact with the large-diameter conveying roller 20 are provided in the document conveying path 13.

  Of the three rollers in pressure contact with the large-diameter conveying roller 20, the first document reading unit 14 is provided between the rollers 22 and 23. The original sent to the first original reading unit 14 moves further down on the original conveyance path 13, that is, the position of the first original reading unit 14 in FIG. 2 from the left to the right. The image data on the first surface, which is the lower surface, is read by the document reading device of the image forming apparatus main body, which is the first document reading device 100 provided below.

  A second document reading unit 15 is provided downstream of the first document reading unit 14 and further downstream of the roller 23. The second document reading unit 15 is provided with a second document reading device 16 composed of a contact image sensor and a conveyance roller 24. The second document reading device 16 is disposed above the document conveyance path 13 so as to face the conveyance roller 24 across the document conveyance path 13. The conveyance roller 24 is provided below the document conveyance path 13, and conveys the document by passing it between the second document reading device 16, which is an opposing member thereof. The document sent to the second document reading unit 15 moves further down on the document conveyance path 13, that is, the position of the second document reading unit 15 in FIG. 2 from the left to the right. The image data on the second surface, which is the upper surface, is read by the second document reading device 16 provided thereabove.

  A document discharge port 17 and a document discharge roller pair 25 are provided on the downstream side of the second document reading unit 15 and at the downstream end of the document transport path 13. The document whose image data has been read is discharged from the document discharge port 17 to the document discharge tray 3 (see FIG. 1) by a document discharge roller pair 25 including a discharge roller 25a and a discharge roller 25b.

  In the document feeding section 10 of the document conveying apparatus 1 having the above-described configuration, the components in the inner portion of the document conveying path 13 that extends in a U-shaped shape from the document supply port 11 to the document discharge port 17 in a vertical direction are conveyed. The unit 30 is configured as a unit.

  Next, a detailed configuration of the transport unit 30 of the document transport apparatus 1 will be described with reference to FIGS. 3 to 5 in addition to FIG. 3 is a perspective view of the transport unit of the document feeding section shown in FIG. 2 as viewed from the left side of FIG. 2, FIG. 4 is a perspective view of the transport unit as viewed from the right side of FIG. FIG. 5 is a perspective view of the transport unit as viewed from above, and shows a state where the transport guide member is removed.

  As shown in FIGS. 3 and 4, the transport unit 30 is surrounded by the document transport path 13 extending in a U-shaped curved shape in the vertical direction from the document supply port 11 to the document discharge port 17 in FIG. 2. The part is unitized.

  The transport unit 30 includes a transport guide member 31 on the lower side of the document transport path 13 around the separation roller 18a and the registration roller 19a. The transport unit 30 includes a large-diameter transport roller 20 and includes a second document reading device 16 (see FIG. 2). As shown in FIG. 3, the large-diameter conveying roller 20 is configured such that a common support shaft 20a extending in the document width direction passes through five relatively narrow rollers 20b.

  When the conveyance guide member 31 is removed from the conveyance unit 30, the internal structure is exposed as shown in FIG. Inside the transport unit 30, two control boards 32 and 33 for controlling the second document reading device 16 are disposed above the transport unit 30. The second document reading device 16 and the control boards 32 and 33 generate heat when the document conveying device 1 is driven.

  Two fans 34 for cooling the inside of the document conveying device 1 are provided at a position downstream of the large-diameter conveying roller 20 in the document conveying direction of the conveying unit 30. The two fans 34 are separately arranged so as to be positioned between two adjacent ones of the five rollers 20b provided in the document width direction.

  As shown in FIG. 2, the air inlet 34 a of the fan 34 contacts from the inside of the large-diameter conveyance roller 20 to a location on the peripheral surface of the large-diameter conveyance roller 20 in the document conveyance path 13, that is, this peripheral surface. It is provided so as to be directed to the original surface. Thus, by driving the fan 34, air flows between the two adjacent rollers 20b.

  Further, as shown in FIG. 2, the fan 34 has an exhaust port 34 b directed to the second document reading device 16, the two control boards 32 and 33, and the document discharge port 17 on the downstream side in the document transport direction. It is provided to do. And the exhaust grille 35 is provided in the downstream end of the conveyance unit 30 to which the air discharged | emitted from this exhaust port 34b goes, as shown in FIG.2 and FIG.4. Air that drives the fan 34 and is discharged from the exhaust port 34 b is sent out of the conveyance unit 30 from the exhaust grill 35 while cooling the second document reading device 16 and the two control boards 32 and 33. .

  As shown in FIG. 2, a wind direction variable mechanism 40 is provided on the downstream side in the air flow direction by the fan 34 of the transport unit 30 configured as described above and outside the exhaust grille 35.

  Next, a detailed configuration around the wind direction varying mechanism 40 will be described with reference to FIGS. 6 is a partially enlarged front view of the vertical section showing the periphery of the wind direction variable mechanism, FIG. 7 is a perspective view of the document conveying device as seen from the direction of the document placing tray, and FIG. 8 is a view of FIG. FIG. 9 is a partially enlarged front view showing the details of the wind direction varying mechanism in a perspective view of the same document conveying device, showing a state where the document placing tray is removed. In FIG. 6, solid arrows indicate the document conveyance path and conveyance direction, and white arrows indicate the air distribution path and distribution direction.

  As shown in FIGS. 6 to 8, the air direction varying mechanism 40 has an air flow between the two places between the place where the transport unit 30 is provided and the place where the document placing tray 2 is provided. Is provided around the side wall member 26 so as to circulate. The wind direction variable mechanism 40 includes a sector gear 41, a pinion 42, a rack 43, a slide member 44, and a variable vane 45 as shown in FIG. Of these components, the sector gear 41, the pinion 42, the rack 43, and the slide member 44 are the housing 5 (see FIG. 7) on the outer side of the document placing tray 2 in the document width direction perpendicular to the document transport direction. ) (See FIG. 8), the variable blade 45 is disposed on the side wall member 26.

  As shown in FIG. 9, the sector gear 41 is provided in the vicinity of the downstream end of the lift member 4 located in the downstream portion of the document placing tray 2. As described above, the sector gear 41 is disposed in the housing 5 outside the lift member 4 in the sheet width direction, and is fixed to the lift member 4. The fan-shaped gear 41 is mounted such that teeth are formed in the arc portion of the fan-shaped plate, the teeth portion faces the downstream side, and the rotation surface is substantially vertical. Accordingly, the teeth of the sector gear 41 also move up and down in conjunction with the lift member 4 that moves up and down while rotating in the vertical plane around the support shaft 4a (see FIG. 1) due to the change in the number of stacked documents D. To do.

  As shown in FIG. 9, the pinion 42 is provided on the downstream side of the sector gear 41 so as to mesh with the sector gear 41. Thereby, the pinion 42 rotates in conjunction with the vertical movement of the lift member 4.

  As shown in FIG. 9, the rack 43 is provided on the further downstream side of the pinion 42 so as to mesh with the pinion 42. The rack 43 is attached to a slide member 44 that extends vertically along a plane on the side of the lift member 4 of the side wall member 26.

  The slide member 44 can be slid up and down along the plane of the side wall member 26 on the lift member 4 side by the action of a slide unit (not shown). As a result, when the pinion 42 rotates, the slide member 44 slides up and down via the rack 43.

  As shown in FIGS. 6 to 9, the variable wing plate 45 is disposed immediately downstream of the downstream end face of the document bundle Dm stacked on the document placing tray 2. The variable wing plate 45 is configured to extend in the document width direction so that an air flow is generated from the transport unit 30 side toward the document placement tray 2 side. The variable slat 45 is rotatably supported by the slide member 44 at the downstream side in the air flow direction, that is, the right side in FIG. 9, and the upstream side, ie, the left side in FIG. The member 46 is rotatably supported. Thereby, when the slide member 44 moves up and down, the variable wing plate 45 can move up and down at the downstream portion in the air circulation direction and change the wind direction.

  With such a wind direction varying mechanism 40, the air direction is switched at the downstream portion of the air discharged from the exhaust port 34b (see FIG. 2) of the fan 34 and further discharged from the transport unit 30 through the exhaust grill 35. It is possible.

  Next, the operation of the wind direction varying mechanism 40 when the document conveyance proceeds will be described with reference to FIGS. 10 and 11 in addition to FIGS. FIG. 10 is a partially enlarged front view showing the details of the wind direction variable mechanism similar to FIG. 9, and shows a state where the conveyance of the original has progressed from FIG. 9, and FIG. 11 shows the periphery of the wind direction variable mechanism similar to FIG. FIG. 8 is a partially enlarged front view of a vertical section showing a state where the document has been conveyed from FIG. As in FIG. 6, in FIG. 11, the solid line arrows indicate the document conveyance path and conveyance direction, and the white arrows indicate the air distribution path and distribution direction.

  First, FIGS. 6 and 9 show a state before the start of document conveyance. In this state, many originals D are placed on the original placement tray 2, and the lift member 4 is located relatively below. In the wind direction varying mechanism 40 shown in FIG. 9, the variable vane plate 45 corresponds to the number of documents stacked on the document placing tray 2, that is, the variable vane plate 45 is moved upward via the sector gear 41, pinion 42, rack 43, and slide member 44. It faces the downstream end face of the document bundle Dm stacked on the document placing tray 2.

  When the document conveying apparatus 1 is started by pressing a reading start button or the like to start reading image data of the document D, the fan 34 rotates to cool the inside of the apparatus.

  As described above, the air discharged from the exhaust port 34b (see FIG. 2) of the fan 34 is discharged from the transport unit 30 through the exhaust grille 35, and stacked on the document placing tray 2 through the wind direction variable mechanism 40. It is sprayed onto the downstream end surface of the original bundle Dm. As a result, the upper-layer document D can be lifted and separation can be promoted.

  Thereafter, when the reading of the image data of the document D continues, the number of documents D on the document loading tray 2 decreases as shown in FIG. Thereby, the downstream end of the lift member 4 is raised by a motor (not shown). Then, when the downstream end of the lift member 4 rises, in the air direction variable mechanism 40, the sector gear 41 rises together with the lift member 4, the pinion 42 rotates counterclockwise in FIG. 10, and the rack 43 and the slide member 44 move downward. The variable wing plate 45 faces downward.

  As a result, the air that has been discharged toward the downstream end surface of the original bundle Dm stacked on the original stacking tray 2 through the air direction variable mechanism 40 is switched and the air is gradually guided downward. It becomes. In this way, the air direction varying mechanism 40 changes the air flow direction downward, that is, toward the document discharge port 17 in accordance with the number of documents stacked on the document tray 2 and the number of sheets supplied from the document tray 2. Switch.

  Here, as shown in FIG. 11, vent holes 27 are provided in the most downstream portion of the bottom plate 2 a of the document placing tray 2 provided below the lift member 4 and the lower portion of the side wall member 26 positioned below the bottom plate 2 a. It has been. The two air vents 27 are discharged from the exhaust grille 35 of the transport unit 30, and the air guided to the document placement tray 2 through the air direction variable mechanism 40 is discharged from the document at the downstream end of the document transport path 13. It is provided to face the outlet 17.

  When the variable slats 45 are directed downward, the air guided downward through the wind direction variable mechanism 40 passes further through the two vent holes 27 as shown in FIG. To the point of.

  On the other hand, when the conveyance of the document proceeds and the number of documents D on the document loading tray 2 decreases, the number of documents D that have been read increases on the document discharge tray 3. Then, the document D is pushed out toward the document discharge tray 3 by the exhaust of the fan 34 guided to the position of the document discharge port 17.

  In this manner, in the document conveying apparatus 1 that separates and conveys the documents D stacked on the document placing tray 2 one by one so as to read the image data on the document surface, the fan 34 that cools the inside is supplied with air. The air flow by the fan 34 follows the flow of the document conveyance because the document conveyance path 13 is circulated on the upstream side of the fan 34 and is provided so as to circulate from the upstream side to the downstream side in the document conveyance direction. The document D can be conveyed without applying a brake. Then, the document D is pulled on the upstream side of the fan 34, and the conveyance of the document D can be facilitated.

  Further, the direction of the air discharged from the exhaust port 34 b of the fan 34 is changed from the downstream end face direction of the document bundle Dm stacked on the document placing tray 2 to the document discharge tray provided on the most downstream side of the document transport path 13. 3 is provided with a wind direction varying mechanism 40 for switching the direction of the document discharge port 17 for discharging the document D, so that the air is effectively blown against the end face of the document bundle Dm by changing the wind direction of the air flow by the fan 34. In addition, the document D can be positively pushed out from the document discharge port 17 to the document discharge tray 3. Thereby, the separation of the document D further proceeds on the document placing tray 2, and the supply performance can be improved. Then, the document D discharged to the document discharge tray 3 stagnates at the position of the document discharge port 17, is caught on the discharge roller 25 a provided in the vicinity thereof, is caught in an unintended part, and is damaged. It is possible. Therefore, the air flow by the fan 34 is also used to improve the conveyance performance of the document D, promote separation of the document D when the document is supplied, and prevent the document D from being damaged at the document discharge port 17. Can be used. In this way, in addition to efficiently cooling the inside of the apparatus by the fan 34, the conveyance performance of the document D can be effectively improved, and the document conveyance apparatus in which the stability of document conveyance is greatly improved. 1 can be provided.

  Further, since the wind direction varying mechanism 40 changes the wind direction in accordance with the number of documents stacked on the document placing tray 2 and / or the number of sheets supplied from the document placing tray 2, the air flow by the fan 34 is required. Accordingly, it is possible to spray the document bundle Dm on the end face of the document bundle Dm from an appropriate direction with an appropriate amount. Therefore, it is possible to enhance the action of separating the document D, and the supply performance at the time of document supply is improved.

  The wind direction varying mechanism 40 includes a sector gear 41 attached to the lift member 4 of the document tray 2 that moves up and down according to the change in the number of documents D, a pinion 42 that meshes with the sector gear 41, and the pinion 42. , A slide member 44 attached to the rack 43 and slidably moved along with the rotation of the pinion 42, and a downstream portion in the air flow direction rotatably supported by the slide member 44. Therefore, the air flow direction of the air flow by the fan 34 is automatically determined from the number of originals loaded on the original placement tray 2 and the original placement tray. It is possible to change according to the number of sheets supplied. This makes it easy to blow an appropriate amount of air against the end face of the document bundle Dm from an appropriate direction. Therefore, the action of separating the document D is further enhanced, and the supply performance of the document D is greatly improved.

  The fan 34 is directed toward the document surface that contacts the peripheral surface of the large-diameter conveyance roller 20 provided on the upstream side of the fan 34 in the document conveyance direction. The document D can be attached to the conveying roller 20. As a result, the adhesion between the large-diameter conveying roller 20 and the original D is increased, and the original D can be conveyed by the large-diameter conveying roller 20 without slipping. Therefore, it is possible to further improve the conveyance performance of the document D.

  A plurality of large-diameter conveying rollers 20 are provided in the document width direction perpendicular to the document conveying direction, and the fan 34 is provided so as to circulate air between these two adjacent rollers 20b. An action of sticking the document D to the large-diameter conveyance roller 20 can be applied at a location closer to the location where the diameter conveyance roller 20 and the document D are in contact with each other. Thereby, the large-diameter conveyance roller 20 and the original D can be further brought into close contact with each other, and the conveyance performance of the original D can be improved.

  Further, the document placement tray 2 and the document discharge tray 3 are configured in two upper and lower stages with their document transport directions reversed, and a document supply port 11 for feeding the document D from the document placement tray 2. A document discharge port 17 for discharging the document D to the document discharge tray 3 is provided on the same side of each tray, and a document conveyance path 13 extending from the document supply port 11 to the document discharge port 17 is U-shaped in the vertical direction. In the document conveying apparatus 1 that is compactly designed in such a shape, the fan 34 efficiently cools the inside of the apparatus by the fan 34 and effectively improves the conveying performance of the document D. Therefore, it is possible to greatly improve the stability of document conveyance.

  Although the embodiments of the present invention have been described above, the scope of the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the invention.

  For example, in the above embodiment, the wind direction varying mechanism 40 uses the sector gear 41, the pinion 42, and the rack 43 to move the variable vane 45 up and down in conjunction with the vertical movement of the lift member 4. The configuration of the wind direction varying mechanism 40 is not limited to this, and the variable vanes 45 may be moved up and down by controlling functional members such as a motor and a solenoid.

  In addition, two fans 34 are separately provided between the adjacent rollers 20b. However, the number, arrangement location, and the like are not limited to this, and other configurations may be used.

  The present invention can be used in all document conveying apparatuses applicable to image forming apparatuses.

1 is a schematic vertical sectional front view of a document conveying device according to an embodiment of the present invention. FIG. 2 is a schematic vertical sectional front view showing a document feeding portion of the document conveying device of FIG. 1. FIG. 2 is a perspective view of the conveyance unit of the document feeding unit, viewed from the left in FIG. FIG. 2 is a perspective view of the conveyance unit of the document feeding unit, viewed from the right side of FIG. FIG. 5 is a perspective view of the transport unit of the document feeding unit as viewed from above, and shows a state where the transport guide member is removed. It is a vertical cross-section part enlarged front view which shows a wind direction variable mechanism periphery. FIG. 3 is a perspective view of the document conveying device viewed from the direction of the document placing tray. FIG. 2 is a perspective view of the document conveying device viewed from the direction of the document placing tray, and shows a state where the document placing tray is removed. It is a partial enlarged front view which shows the detail of a wind direction variable mechanism. FIG. 9 is a partially enlarged front view showing details of the air direction variable mechanism, and shows a state where the conveyance of the original has progressed from FIG. 9. FIG. 7 is a partially enlarged front view of the vertical section showing the periphery of the wind direction variable mechanism, and shows a state where the conveyance of the original has progressed from FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Document conveying apparatus 2 Document loading tray 3 Document discharge tray 4 Lift member 5 Housing 10 Document feeding section 11 Document supply port 13 Document transport path 14 First document reading section 15 Second document reading section 16 Second document reading Device 17 Document discharge port 20 Large-diameter conveying roller (conveying roller)
20b Roller 26 Side wall member 27 Ventilation hole 30 Transport unit 32, 33 Control board 34 Fan 34a Inlet port 34b Exhaust port 35 Exhaust grill 40 Wind direction variable mechanism 41 Fan gear 42 Pinion 43 Rack 44 Slide member 45 Variable wing plate

Claims (6)

In a document conveying device that separates and conveys documents stacked on a document placing tray one by one so as to read image data on a document surface,
A fan for cooling the inside is provided in such a direction that air flows through the document conveyance path on the upstream side of the fan and flows from the upstream side to the downstream side in the document conveyance direction, and is discharged from the exhaust port of the fan. A wind direction variable mechanism for switching the air wind direction from the downstream end face direction of the bundle of documents stacked on the document placing tray to the document discharge port direction for discharging the document to the document discharge tray provided on the most downstream side of the document transport path. An original conveying apparatus comprising:   2. The document conveying device according to claim 1, wherein the wind direction varying mechanism changes the wind direction in accordance with the number of documents stacked on the document placing tray and / or the number of sheets supplied from the document placing tray. .   The wind direction varying mechanism includes a fan-shaped gear attached to a lift member of the document placing tray that moves up and down according to a change in the number of stacked documents, a pinion that meshes with the fan-shaped gear, a rack that meshes with the pinion, and a rack that A slide member attached and slidably moved along with the rotation of the pinion, and a variable wing plate that is rotatably supported by the slide member in a downstream portion in the air flow direction and changes the wind direction as the slide member moves. The document feeder according to claim 1 or 2.   4. The fan according to claim 1, wherein an air inlet of the fan is directed to a document surface that contacts a peripheral surface of a conveyance roller provided upstream of the fan in a document conveyance direction. 5. Document transport apparatus described in 1.   5. The plurality of transport rollers are provided in a document width direction perpendicular to the document transport direction, and the fan is provided so as to circulate air between two adjacent rollers. Document transport apparatus described in 1.   The document placement tray and the document discharge tray are configured in two upper and lower stages with the document transport direction opposite to each other, a document supply port for feeding a document from the document placement tray, and a document discharge tray The document discharge port for discharging the document is provided on the same side of each tray, and the document transport path extending from the document supply port to the document discharge port is curved in a U-shape in the vertical direction. The document conveying device according to claim 1, wherein

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