JP2008083442A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus, where the turning direction of an opening/closing cover and a manual paper feed tray and the pull-out direction of a carrier unit are all on the same face side of an apparatus body, further, the manual paper feed tray constitutes a part of the opening/closing cover and is constituted so as to be opened, together with the opening/closing cover, and the manual paper feed tray is pulled out together with a paper conveying unit, by which the paper conveying unit can be pulled out, even while the opening/closing cover is opened. <P>SOLUTION: The manual paper feed tray 6 is formed, in such a manner that when the manual paper feed tray 6 is opened, together with the opening/closing cover 24, the upper edge part 6b of the manual paper feed tray 6 becomes horizontal. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus in which a paper transport unit for transporting paper is provided so as to be able to be pulled out from an image forming apparatus main body in an image forming apparatus such as a copying machine or a printer.

  2. Description of the Related Art Conventionally, in an image forming apparatus such as a printer, a paper feed cassette that accommodates paper at the bottom of the apparatus main body is detachably attached to the apparatus main body, and a pickup roller or the like disposed above the paper feed cassette A sheet feeding unit configured to sequentially feed the sheets stored in the sheet feeding cassette one by one and transport the sheet to an image forming unit and a fixing unit by a transport roller, thereby forming an image on the sheet. Has been.

  Here, in the image forming apparatus configured as described above, the paper supplied from the paper feeding cassette is jammed on the upstream side or the downstream side in the paper conveyance direction of the image forming unit or the fixing unit, and a jam occurs. There is. In such a case, in order to enable the jam processing to be performed easily and quickly, the separation feeding unit and the conveyance roller described above are unitized as a sheet conveyance unit and can be pulled out from the apparatus main body. A forming apparatus has been developed (for example, Patent Document 1).

  Further, in general, in an image forming apparatus, when a paper having a different size or type from the paper stored in the paper feed cassette is used, it is not necessary to store the target paper in the paper feed cassette each time. In many cases, a manual feed tray that can supply paper without using a paper feed cassette is provided. However, when the paper supplied from the manual feed tray is jammed, it is easy to handle a jam. An image forming apparatus has been developed in which a manual feed tray can be pulled out integrally with the above-described paper transport unit so that it can be performed (for example, Patent Document 2).

  By the way, in the image forming apparatus, in order to maintain an intermediate transfer member or the like disposed inside the apparatus or to replace a toner container filled with toner, an opening / closing that can be opened / closed on a part of the outer cover is provided. Although the cover is provided, in the image forming apparatus described in Patent Document 2, the opening direction of the opening / closing cover and the direction in which the manual feed tray and the paper transport unit are pulled out are unified on the front side of the apparatus main body. These workability are further improved.

Further, in the image forming apparatus described in Patent Document 2, the manual feed tray is configured to be openable and closable with respect to the apparatus main body in order to reduce the size of the apparatus main body, and is further closed to reduce the number of parts of the apparatus main body. The manual feed tray constitutes a part of the exterior cover of the apparatus main body. A part of the exterior cover on the front side of the apparatus main body on which the manual feed tray is arranged is an open / close cover that can be opened and closed for maintenance. In order to enlarge the opening, the open / close cover and the manual feed tray The rotation fulcrum is provided on a concentric shaft so that when the opening / closing cover is opened, the manual feed tray is also opened together with the opening / closing cover, thereby improving workability such as maintenance.
JP 2003-177649 A JP 2006-184855 A

  However, as in the image forming apparatus described in Patent Document 2, if the opening direction of the opening / closing cover and the direction for pulling out the manual feed tray and the paper transport unit are unified on the front side of the apparatus main body, a paper jam occurs. In this case, the user may accidentally open the open / close cover without pulling out the paper transport unit. At this time, since the jammed paper cannot be seen even if the opening / closing cover is opened, the user notices that it is necessary to pull out the paper transport unit, and pulls out the paper transport unit without closing the open / close cover. was there.

  Here, in the image forming apparatus 100 described in Patent Document 2, the sheet conveying unit 103 is placed on the front side of the apparatus main body (right side in FIG. 6) in a state where the manual feed tray 102 is opened together with the opening / closing cover 101 as shown in FIG. When pulled out, the upper end portion 102a of the manual feed tray 102 comes into contact with the inner edge 101a of the opening / closing cover 101, and the upper end portion 102a of the manual feed tray 102 may be deformed or damaged. Therefore, after closing the opening / closing cover 101, the paper transport unit 103 has to be pulled out, and workability at the time of jam processing is not good.

  In the present invention, in view of the above-described circumstances, the rotation direction of the open / close cover and the manual feed tray and the drawing direction of the paper transport unit are all on the same surface side of the apparatus main body, and the manual feed tray constitutes a part of the open / close cover. In addition, in the image forming apparatus configured to be opened together with the opening / closing cover and further configured to pull out the manual feed tray together with the sheet conveying unit, the sheet conveying unit can be pulled out even when the opening / closing cover is opened. It is an object of the present invention to provide an image forming apparatus that can be used.

  To achieve the above object, the present invention comprises an opening / closing cover configured to be openable / closable on a side surface of an exterior cover with a lower end as a rotation fulcrum, and a part of the opening / closing cover. A manual feed tray configured to be opened and closed independently is provided at the center, and the manual feed tray and a manual feed path through which paper fed from the manual feed tray is conveyed are unitized as a paper feed unit. In the image forming apparatus in which the paper transport unit is configured to be able to be pulled out from the apparatus main body, the manual feed tray is surrounded by the open cover at an upper end and a side end in a state of being opened together with the open / close cover. A surface of the upper end facing the inner edge of the opening / closing cover is formed so as to have a downward slope on the horizontal or inner surface side.

  According to the present invention, in the image forming apparatus having the above-described configuration, a sheet feeding cassette that stores a bundle of sheets is provided at a lower portion of the apparatus main body, and sheets are supplied to the sheet conveying unit from the sheet feeding cassette. The pickup roller and the feed roller that perform the transfer, and the sheet conveyance path for conveying the sheet to the transfer area are unitized.

  Further, according to the present invention, in the image forming apparatus having the above-described configuration, the paper feed cassette is configured to be drawable from the apparatus main body, and when the paper transport unit is pulled out from the apparatus main body, the paper feed cassette is pulled out at the same time. It is characterized by that.

  According to the first configuration of the present invention, when the manual feed tray is opened, the upper end of the manual feed tray is formed to be horizontal or the height of the upper end is lowered as it approaches the inner edge. Even if the paper transport unit is pulled out of the main body with the tray open together with the open / close cover, the upper end of the manual feed tray contacts the inner edge of the open / close cover, and the upper end of the manual feed tray is deformed or damaged. Therefore, the paper transport unit can be pulled out with the open / close cover open, and the jam handling workability can be improved.

  According to the second configuration of the present invention, in the image forming apparatus having the first configuration, the sheet transport unit and the manual transport path are exposed to the outside of the apparatus body by pulling out the sheet transport unit from the apparatus body. Therefore, it is possible to easily remove the jammed paper in the paper conveyance path or the manual conveyance path.

  According to the third configuration of the present invention, in the image forming apparatus having the second configuration, when a paper jam occurs in a state where the paper straddles the paper feed cassette and the paper transport path, the paper transport unit is pulled out. At this time, since the paper is prevented from being damaged, the paper can be easily removed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of an image forming apparatus according to the present invention, and shows a color laser printer as an example. FIG. 2 is an overall perspective view showing a state where the manual feed tray is opened, and FIG. 3 is an overall perspective view showing a state where the toner container is being removed. In FIG. 1, the right side is the front side of the image forming apparatus.

  A paper feed cassette 2 for storing a bundle of paper is provided at the lower part of the image forming apparatus main body 1. The paper P stored above the paper feed side (right side in FIG. 1) of the paper feed cassette 2 is provided. Is disposed in order from the uppermost sheet, and further, on the downstream side in the sheet conveying direction, a feed roller 4 is disposed to convey the sheet P fed by the pickup roller 3 further downstream. Yes.

  The sheet feeding cassette 2 is provided with a retard roller 5 so as to be in pressure contact with the feed roller 4. When a plurality of sheets P are simultaneously fed from the pickup roller 3, the feed roller 4 and the retard roller 5 are retarded. By rolling the paper P at the nip portion with the roller 5, double feeding is prevented. The paper feed cassette 2 is configured to be detachable from the apparatus main body 1 and can be removed by being pulled out to the front side of the apparatus main body 1.

  A manual feed tray 6 is provided on the front side of the apparatus main body 1 so as to constitute a part of the exterior cover. The manual feed tray 6 is configured such that a lower end portion thereof is rotatably supported by a rotation fulcrum 6a with respect to the apparatus main body 1, and is configured to be able to be opened and closed by rotating about this, as shown in FIG. By opening the manual feed tray 6, paper can be placed on the manual feed tray 6. In the vicinity of the rotation fulcrum 6a, a manual transport path R2 for transporting the paper P placed on the manual feed tray 6 to a paper transport path R1 described later is provided, and along this manual transport path R2. A paper feed roller 7 is disposed.

  A reversing roller 8 is disposed above the feed roller 4 to convey the paper P supplied from the paper feed cassette 2 or the manual feed tray 6 to the rear of the apparatus main body 1. In the apparatus main body 1, a paper conveyance path R1 for conveying the paper P from the reverse roller 8 to the rear of the apparatus main body 1 is provided, and the paper is reversed in order from the upstream in the paper conveyance direction along the paper conveyance path R1. A roller 8, a registration roller pair 9, a secondary transfer roller 10, and a fixing roller pair 11 are arranged.

  An intermediate transfer belt 12 that is an intermediate transfer member is rotatably disposed above the sheet conveyance path R1. The intermediate transfer belt 12 is stretched around a driving roller 13, a driven roller 14, a tension roller 15 and a primary transfer roller 16, and when the driving roller 13 is rotationally driven, a clock as indicated by an arrow A along with the above-described rollers. It is designed to rotate in the direction. A sheet made of dielectric resin is used for the intermediate transfer belt 12, and a belt in which both ends thereof are overlapped and joined to form an endless shape, or a belt without a seam (seamless) is preferably used.

  The driving roller 13 abuts on the secondary transfer roller 10 via the intermediate transfer belt 12 to form a secondary transfer area, and downstream of the abutting portion (secondary transfer area) in the rotation direction of the intermediate transfer belt 12. On the side, the cleaning roller 17 is pressed against the intermediate transfer belt 12 so as to face the driving roller 13. Further, the primary transfer roller 16 is in contact with a photosensitive drum 18 which is an image carrier via the intermediate transfer belt 12.

  The photosensitive drum 18 is driven to rotate counterclockwise by a driving device (not shown), and the charging roller 19, which is a contact type charger, the developing unit 20, the primary transfer roller 16, and the cleaning unit 21 are sequentially arranged from above along the rotation direction. Is arranged. The charging roller 19 abuts on the upper portion of the photosensitive drum 18 and rotates following the rotation of the photosensitive drum 18. A toner container 22 that supplies toner to the developing unit 20 is disposed above the cleaning unit 21, and a laser optical unit 23 that uses a known optical system is disposed above the developing unit 20. Yes.

  The toner container 22 disposed in the apparatus main body 1 is configured to be detachable from the apparatus main body 1 in order to facilitate toner replenishment work, and the apparatus main body 1 can be attached and detached. A part of the exterior cover on the front side is an openable / closable cover 24. Then, as shown in FIG. 3, the opening / closing cover 24 is pivoted about the pivot fulcrum 24a and opened to open the portion, and the toner container 22 can be replaced through the opening. It has become.

  Further, in the apparatus main body 1 according to the present invention, the opening formed by opening the opening / closing cover 24 is made larger so that maintenance of the intermediate transfer belt 12 and the like can be performed from this opening. On the front side of the main body 1, almost the entire surface except for the paper feed cassette 2 is an open / close cover 24. For this reason, the above-described manual feed tray 6 is also a part of the opening / closing cover 24. By providing the rotation fulcrum 24a of the opening / closing cover 24 on the axis concentric with the rotation fulcrum 6a of the manual feed tray 6, the manual feed tray 6 is provided. Can be opened and closed together with the opening / closing cover 24. When the opening / closing cover 24 is opened, the manual feed tray 6 is also opened at the same time.

  The developing unit 20 has a substantially cylindrical shape as a whole, and is supported rotatably at both ends thereof. The interior of the developing unit 20 is divided into four rooms by a cross-shaped partition wall, which corresponds to toners of each color of black (K), cyan (C), magenta (M), and yellow (Y). Four developing units 25K, 25C, 25M, and 25Y are configured. In addition, arrangement | positioning of the image development apparatus to illustrate is an example, Comprising: It is not limited to this.

  Each of the developing devices 25K to 25Y includes developing rollers 26, 27, 28, and 29 that are individually driven to rotate. Further, a driving unit (not shown) is connected to the developing unit 20, and by driving the driving unit, the developing unit 20 rotates, and any of the developing rollers 26 to 29 of the developing devices 25K to 25Y. These are selectively arranged to face the photosensitive drum 18 so that the developing operation is performed.

  The downstream end portion of the paper transport path R1 is provided with a paper discharge path R3 for transporting the paper P after image fixing upward and discharging it to the discharge tray 30 so as to be continuous therewith. A transport roller pair 31 is disposed along R3, and a discharge roller pair 32 is disposed at the downstream end of the paper discharge path R3. Further, the transport roller pair 31 and the discharge roller pair 32 also serve as switchback rollers when performing duplex printing, and the upstream end of the paper discharge path R3 is connected to the transport roller pair 31 and A duplex printing conveyance path R4 is provided for conveying the paper P switched back by the discharge roller pair 32 to the secondary transfer region again.

  This duplex printing conveyance path R4 extends from the upstream end of the paper discharge path R3 to the lower side of the apparatus main body 1, changes the paper conveyance direction to the front of the apparatus main body 1 at the upper part of the paper feed cassette 2, and its downstream end is a reverse roller. 8 and upstream of the registration roller pair 9 so as to merge with the sheet conveyance path R1, and along the duplex printing conveyance path R4, the duplex conveyance roller pairs 33, 34, 35 is arranged.

  Regarding the image forming operation by the image forming apparatus configured as described above, first, the operation during single-sided printing will be described. When the photosensitive drum 18 is rotationally driven, the charging roller 19 is driven to rotate, and the surface of the photosensitive drum 18 is uniformly charged. Based on the input image signal, the laser optical unit 23 operates to irradiate the charged photosensitive drum 18 with laser light, and an electrostatic latent image is formed on the surface of the photosensitive drum 18. The electrostatic latent image thus formed is developed by the developing unit 20 as described above, and is primarily transferred by the primary transfer roller 16 onto the intermediate transfer belt 12 that rotates clockwise.

  That is, in the case of monochrome image formation, a black toner image is formed on the photosensitive drum 18 by disposing only the developing roller 26 of the developing device 25K so as to face the photosensitive drum 18 on which the electrostatic latent image is formed. The black toner image formed on the photosensitive drum 18 is transferred onto the rotating intermediate transfer belt 12 by the primary transfer roller 16 to form a monochrome image.

  In the case of color image formation, the developing unit 20 is rotated by driving the driving unit, and the developing rollers 26 to 29 of the four developing devices 25K to 25Y are sequentially and selectively arranged to face the photosensitive drum 18. The toner images of the respective colors are formed on the photosensitive drum 18, and the toner images of the respective colors formed on the photosensitive drum 18 are transferred onto the intermediate transfer belt 12 that is sequentially rotated by the primary transfer roller 16, and these are transferred. A color image is formed by superposition. In the case of color image formation, the cleaning roller 17 is separated from the intermediate transfer belt 12 during the primary transfer operation.

  Then, in a predetermined secondary transfer region, intermediate transfer is performed by the secondary transfer roller 10 onto the paper P that is supplied from the paper feed cassette 2 or the manual feed tray 6 and further transported through the paper transport path R1 by the registration roller pair 9. A monochrome image or a color image on the belt 12 is secondarily transferred at once. The sheet P on which the monochrome image or the color image is transferred in this way is transported through the sheet transport path R1, and the toner image on the sheet P is heated and fixed by the fixing roller pair 11. After fixing, the paper P is transported from the paper transport path R1 to the paper discharge path R3, and is discharged to the discharge tray 30 by the transport roller pair 31 and the discharge roller pair 32.

  The untransferred toner that remains on the photosensitive drum 18 without being primary transferred is removed by the cleaning unit 21, and the untransferred toner that remains on the intermediate transfer belt 12 without being secondary transferred is removed by the cleaning roller 17. Removed. The removed toner is conveyed to a waste bottle (not shown) by a toner collecting device such as a collecting screw.

  Next, the operation during duplex printing will be described. First, an image is formed on the surface of the paper P in the same manner as in the single-side printing described above. Then, the sheet P that has undergone single-sided printing is discharged from the sheet transport path R1 to the discharge tray 30 via the discharge path R3. In the case of double-sided printing, the trailing edge of the sheet P is the discharge path R3. When entering, the rotation direction of the conveyance roller pair 31 and the discharge roller pair 32 is reversed, and the paper P is pulled back into the apparatus main body 1. The pulled-back paper P is not returned to the paper transport path R1, but is transported to the duplex printing transport path R4.

  Then, the sheet P conveyed to the duplex printing conveyance path R4 is conveyed by the duplex conveyance roller pairs 33, 34 and 35 and returned to the upstream side of the registration roller pair 9 in the sheet conveyance path R1, and is the same as in the above-described single-side printing. After the image is also formed on the remaining back surface, the sheet is discharged to the discharge tray 30 via the paper transport path R1 and the paper discharge path R3.

  In the image forming apparatus configured as described above, the paper P transported in the apparatus main body 1 may be jammed in the middle of the paper transport path R1 or the duplex printing transport path R4. Therefore, a portion surrounded by a broken line in FIG. 1 is unitized as a paper transport unit 36 and configured to be able to be pulled out from the apparatus main body 1. By removing the paper transport unit 36, jamming can be easily performed. Can be done.

  Hereinafter, the paper transport unit 36 will be described with reference to FIGS. 1, 4, and 5. 4 is an overall perspective view showing a state in which the paper transport unit is pulled out, and FIG. 5 is a partial cross-sectional view showing a state in which the opening / closing cover is opened.

  As indicated by a broken line in FIG. 1, a part of the sheet conveyance path R1, and a pickup roller 3, a feed roller 4, a reverse roller 8, a registration roller pair 9, and a secondary transfer roller 10 disposed along the sheet conveyance path R1. The pair of double-sided conveyance rollers 34 and 35 arranged along the manual conveyance route R2, the duplex printing conveyance route R3, and the duplex printing conveyance route R3 are unitized as a sheet conveyance unit 36.

  In addition, when paper is fed from the manual feed tray 6, the paper P may be jammed at a position straddling the manual feed tray 6 and the manual feed path R2, so that jam processing in such a case is facilitated. The manual feed tray 6 is also configured to be pulled out integrally with the paper transport unit 36. Further, since the paper P may be jammed at a position straddling the paper feed cassette 2 and the paper transport path R1, when the paper transport unit 35 is pulled out, the paper feed cassette 2 is also pulled out at the same time.

  When a jam occurs, as shown in FIG. 4, by pulling out the paper transport unit 36 to the front side of the apparatus body 1, one of the manual transport path R2, the paper transport path R1, and the duplex printing transport path R3 is displayed. The sheet P can be exposed to the outside of the apparatus main body 1, and the paper P jammed in each conveyance path can be easily removed by pulling out the paper conveyance unit 36 from the apparatus main body 1 in this way.

  Here, when performing the jam processing, the user may accidentally open the opening / closing cover 24 without pulling out the paper transport unit 36. At this time, since the jammed paper P cannot be visually recognized even when the opening / closing cover 24 is opened, the user may pull out the paper transport unit 36 without closing the opening / closing cover 24. Therefore, in the image forming apparatus 1 according to the present invention, the upper end portion 6b of the manual feed tray 6 is formed in a tapered shape having a predetermined angle, and the manual feed tray 6 is opened together with the opening / closing cover 24 as shown in FIG. In this case, the upper end 6b of the manual feed tray 6 is configured to be horizontal.

  As a result, even when the paper transport unit 36 is pulled out to the front side of the apparatus main body 1 (right side in FIG. 5) with the opening / closing cover 24 opened, the upper end 6b of the manual feed tray 6 contacts the inner edge 24b of the opening / closing cover 24. Since the upper end portion 6b of the manual feed tray 6 is not deformed or damaged, the paper transport unit 36 can be pulled out with the open / close cover 24 opened, and the jam handling workability can be improved. it can.

  As described above, the taper angle of the upper end portion 6b of the manual feed tray 6 is determined by the surface where the upper end portion 6b of the manual feed tray 6 faces the inner edge 24b when the manual feed tray 6 is opened together with the opening / closing cover 24. In addition to being formed so as to be horizontal, the same effect can be obtained even when the surface where the upper end portion 6b of the manual feed tray 6 and the inner edge 24b face each other becomes an inclined surface that becomes lower as it approaches the inner surface side.

  In addition, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above embodiment, the upper end portion 6b of the manual feed tray 6 is formed in a tapered shape. However, when the manual feed tray 6 is opened, the upper end portion 6b of the manual feed tray 6 is formed in an arc shape if the height decreases from the outer surface side toward the inner surface side. May be.

  In the above embodiment, the portion surrounded by the broken line in FIG. 1 is unitized as the paper transport unit 36. However, the paper transport unit is not limited to this configuration. For example, only the manual tray 6 and the manual transport path R2 are included. May be a paper transport unit. Furthermore, in the above-described embodiment, a color laser printer has been illustrated and described as an example of an image forming apparatus, but the configuration of the present invention can also be applied to a monochrome printer.

  INDUSTRIAL APPLICABILITY The present invention can be used in an image forming apparatus such as a copying machine or a printer in which a paper transport unit that transports paper is provided so as to be able to be pulled out from the apparatus main body.

FIG. 3 is a side sectional view of the image forming apparatus according to the present invention. FIG. 3 is an overall perspective view showing a state where a manual feed tray is opened. FIG. 4 is an overall perspective view showing the middle of removing the toner container. FIG. 4 is an overall perspective view showing a state in which the paper transport unit is pulled out. These are the fragmentary sectional views which show the state which opened the opening-and-closing cover. These are the fragmentary sectional views which show the structure of the conventional manual feed tray and the opening / closing cover.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Paper feed cassette 3 Pickup roller 4 Feed roller 6 Manual feed tray 6a Rotation fulcrum 6b Upper end part 7 Paper feed roller 8 Reverse roller 9 Registration roller pair 10 Secondary transfer roller 24 Opening / closing cover 24a Rotation fulcrum 24b Inner edge 33, 34, 35 Double-sided conveyance roller pair 36 Paper conveyance unit R1 Paper conveyance path R2 Manual conveyance path R3 Paper discharge path R4 Double-sided printing conveyance path

Claims (3)

An opening / closing cover configured to be openable / closable with the lower end as a pivot point on the side of the exterior cover;
A part of the open / close cover, and a manual feed tray configured to be independently openable / closable around a pivot point of the open / close cover; and
In the image forming apparatus in which the manual feed tray and a manual feed path through which the paper supplied from the manual feed tray is conveyed are unitized as a paper feed unit, and the paper feed unit can be pulled out from the apparatus main body. ,
When the manual feed tray is opened together with the open / close cover, the upper end and the side end are surrounded by the open cover, and the surface of the upper end facing the inner edge of the open / close cover is on the horizontal or inner surface side. An image forming apparatus having a downward slope. The lower part of the apparatus main body is provided with a paper feed cassette for storing a bundle of paper,
2. The paper transport unit includes a pickup roller and a feed roller for supplying paper from the paper feed cassette, and a paper transport path for transporting the paper to a transfer area. Image forming apparatus.   3. The image according to claim 2, wherein the paper feed cassette is configured to be drawable from the apparatus main body, and the paper feed cassette is pulled out simultaneously when the paper transport unit is pulled out from the apparatus main body. Forming equipment.

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