JP2006153973A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus with a manual paper supply unit avoiding jamming or slanted transporting. <P>SOLUTION: A paper transporting path 10 is installed in a second quadrant and a third quadrant of a rectangular coordinate system with a rotational center of a photoreceptor drum 132 provided in a unit for black 131B as an origin. Furthermore, the manual paper supply unit 22 is installed in a fourth quadrant of the rectangular coordinate system. Therefore, it is not necessary to provide a manual paper supply transporting path 27 at an acute angle to the paper transporting path 10. As the result, even when thick paper or strong paper is used for paper sheet Q, occurrences of jamming and the slanted transporting can be effectively suppressed and stable paper supply can be carried out. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer apparatus, and a facsimile apparatus, and more particularly to an image forming apparatus including a manual sheet feeding device as a sheet feeding path.

In recent years, in order to shorten the conveyance path and increase the printing speed, an image forming apparatus having a vertical conveyance path extending in a substantially vertical direction (vertical direction) has been adopted. In general, in such an image forming apparatus, two paths of a sheet feeding cassette and a manual sheet feeding unit are provided as a sheet feeding path to the image forming unit, and the two paths before the registration roller or the upstream relay roller. Are supposed to join. Among these, the manual paper feed unit includes a manual paper feed tray and a paper feed roller, and the paper placed on the manual paper feed tray is fed from the manual paper feed tray by the rotation operation of the paper feed roller. Is sent out to the paper transport path. (For example, refer to Patent Document 1).
JP 2003-73038 A

  However, in the conventional image forming apparatus having the vertical conveyance path, the sheet conveyance path is provided on the side surface side in the image forming apparatus, and the manual sheet feeding unit is provided on the sheet conveyance path side. Therefore, it is necessary to provide the manual paper feed path at a steep angle with respect to the paper path. In addition, the paper placed on the manual paper feed unit may be not only thin paper with weak stiffness but also thick paper or strong paper. Therefore, when such a stiff paper is used in a state where the manual paper feeding path is provided at a steep angle with respect to the paper feeding path, jamming and oblique feeding occur, and stable feeding is performed. There was a problem that it became difficult.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus including a manual sheet feeding unit that can avoid jamming and oblique conveyance.

  In order to achieve the above object, according to the first aspect of the present invention, there is provided an image forming apparatus that includes an apparatus main body and an image carrier that is rotatably supported in a predetermined direction and forms an image on a sheet. Disposed on the upstream side of the image forming unit and transports the sheet toward the image forming unit, and disposed on the downstream side of the image forming unit. The image forming unit forms an image and discharges the sheet. Connects the paper discharge path for storing paper, the paper transport path provided between the paper feed section and the paper discharge section, the manual paper feed unit for transporting paper into the main unit, and the manual paper feed unit and paper transport path. In the image forming apparatus including the manual sheet feeding conveyance path, the sheet conveyance path is disposed in the second quadrant and the third quadrant of the rectangular coordinate system with the rotation center of the image carrier as the origin, and the rectangular coordinate system A manual feed unit is arranged in the fourth quadrant. .

  According to the first aspect of the present invention, there is no need to provide the manual paper feed path at a steep angle with respect to the paper path. Therefore, even when thick paper or stiff paper is used, it is possible to suppress the occurrence of jamming and oblique conveyance in the manual paper feeding unit, and stable paper feeding can be performed.

  According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the paper feed unit is arranged in the third quadrant and the fourth quadrant of the rectangular coordinate system, and the manual paper feed conveyance path is It is arranged above the paper portion and in the fourth quadrant of the rectangular coordinate system.

  According to the second aspect of the present invention, it is possible to effectively utilize the empty space above the sheet feeding unit when providing the manual sheet feeding conveyance path in the apparatus main body. Accordingly, it is not necessary to provide a manual paper feed conveyance path on the end side in the image forming apparatus provided with the paper conveyance path, and it is possible to avoid an increase in the size of the apparatus.

  According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect, a manual paper feed transport unit having a manual paper feed transport path is provided. It is provided so that it can be opened and closed with respect to the main body.

  According to the third aspect of the present invention, even when a jam occurs in the manual paper feed conveyance path, the jam handling is performed only by opening the manual paper feed conveyance unit when processing the jammed paper. Yes. Therefore, operability when removing jammed paper is improved, and jam processing is facilitated.

  According to the present invention, it is possible to suppress the occurrence of jamming and oblique conveyance in the manual sheet feeding unit, and it is possible to perform stable sheet feeding.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram illustrating an overall configuration of an image forming apparatus according to an embodiment of the present invention, and FIG. 2 is a perspective view illustrating an external configuration of the image forming apparatus according to an embodiment of the present invention. As shown in FIG. 1, the image forming apparatus 1 is a so-called vertical conveyance type image forming apparatus, and the image forming apparatus 1 is disposed below the box-shaped apparatus main body 2 and the apparatus main body 2. The sheet feeding unit 3, the image forming unit 4 disposed above the sheet feeding unit 3, the fixing unit 5 disposed on the upper left side of the image forming unit 4, and the apparatus main body 2 are disposed above. And a discharge unit 6.

  The paper feed unit 3 is disposed on the upstream side of the image forming unit 4 and includes a paper feed cassette 7 in which the paper P is stored. Then, the sheet P is fed from the sheet feeding cassette 7 to the sheet conveying section 9 via the pair of rolling rollers 11a and 11b for preventing the feeding of the sheet P fed by the rotation of the sheet feeding roller 8. Sent out. The sheet P is conveyed toward the image forming unit 4 by a sheet conveying path 10 provided between the sheet feeding unit 3 and the discharge unit 6 via the registration roller pairs 12a and 12b. It has become. The paper feed cassette 7 is configured to be detachable from the apparatus main body 2.

  The image forming unit 4 forms a predetermined toner image on the paper P by an electrophotographic process. The image transfer unit 131 and a transfer belt onto which the toner image is transferred by the image transfer unit 131. 136 and a secondary transfer roller 137 for further transferring the toner image on the transfer belt 136 to the paper P conveyed from the paper feed cassette 7. The secondary transfer roller 137 is provided at a position immediately to the left of the image transfer unit 131.

  The image forming apparatus 1 in the present embodiment is a so-called tandem type color image forming apparatus, and the image transfer units 131 are sequentially arranged from the upstream side (the right side of the paper surface of FIG. 1) to the downstream side. A yellow unit 131Y, a magenta unit 131M, a cyan unit 131C, and a black unit 131B are provided. Each of these units 131Y, 131M, 131C, 131B is positioned and attached to each device in the apparatus main body 2 with a predetermined relative positional relationship.

  Each of the units 131Y, 131M, 131C, and 131B includes a photosensitive drum 132 as an example of an image carrier that is pivotally supported in a predetermined direction (counterclockwise) at the center position, and each photosensitive drum. A developing device 133 is provided on the right side of 132 in FIG. Then, the toner is supplied from the developing device 133 to the peripheral surface of the photosensitive drum 132 that rotates about the axis in the counterclockwise direction, whereby a toner image is formed on the peripheral surface of the photosensitive drum 132. ing.

  Further, a cleaning device 20 is provided at the upper left position of each photosensitive drum 132 in FIG. 1 to remove the residual toner on the circumferential surface of the photosensitive drum 132 and clean it. A charging device is positioned below the cleaning device 20. 134 is provided. The peripheral surface of the photosensitive drum 132 cleaned by the cleaning device 20 is directed to the charger 134 for a new charging process.

  An exposure device 135 is provided immediately below the photosensitive drum 132. The exposure device 135 irradiates the peripheral surface of the photosensitive drum 132 uniformly charged by the charger 134 with laser light based on image data input from an image reading device (not shown). An electrostatic latent image is formed on the peripheral surface of each photosensitive drum 132. By supplying toner from the toner container of the developing device 133 to the electrostatic latent image, a toner image is formed on the peripheral surface of the photosensitive drum 132, and this toner image is transferred onto the paper P being conveyed by the transfer belt 136. It is transcribed.

  The transfer belt 136 is stretched between the driving roller 136a and the driven roller 136b so that the surface side thereof is in contact with the circumferential surface of the photosensitive drum 132 at a position immediately above the units 131Y, 131M, 131C, and 131B. A primary transfer roller 136c is provided directly above each photosensitive drum 132 via a transfer belt 136. The transfer belt 136 is lifted from the photosensitive drum 132 by being pressed by the primary transfer roller 136c. Is to be prevented.

  The toner image formed on each photosensitive drum 132 at a predetermined time lag with the rotation of the transfer belt 136 driven by the driving roller 136a is rotated clockwise in the overcoating state by the primary transfer roller 136c. Is transferred to the surface of the transfer belt 136 that circulates around the surface. Next, the color image formed on the surface of the transfer belt 136 is transferred to the secondary transfer roller 137 and the driving roller 136a by the paper feeding unit 3 arranged on the upstream side of the image forming unit 4 (the lower side of the paper surface in FIG. 1). Are transferred onto the paper P conveyed between the two, and a color transfer image is formed on the paper P.

  Further, a transfer belt cleaning device 138 is provided on the right side of the driven roller 136b, and the toner remaining on the surface of the transfer belt 136 after the transfer of the toner image onto the paper P is transferred by the transfer belt cleaning device 138. Removed. As a result, the cleaned transfer belt 136 is supplied to the photosensitive drum 132.

  The fixing unit 5 performs a fixing process on the transfer image transferred to the paper P by the image forming unit 4. The fixing unit 5 is disposed opposite to the heat roller 141 heated by the energization heating element and the heat roller 141. Is provided with a pressure roller 142 that is pressed against and contacted with the peripheral surface of the heat roller 141. The transferred image transferred to the paper P by the secondary transfer roller 137 in the image forming unit 4 is fixed by a fixing process by heating when the paper P passes between the heat roller 141 and the pressure roller 142. The Thereafter, the paper is discharged to the discharge unit 6 disposed on the downstream side of the image forming unit 4 (upper side of the paper surface in FIG. 1) via the discharge roller pair 13, and the paper P is accommodated in the discharge unit 6. It is the composition which becomes.

  Further, in the image forming apparatus 1 according to the present embodiment, a reverse conveyance unit 14 is disposed, and the reverse conveyance unit 14 is disposed on the side surface 1a side of the apparatus main body 2 as shown in FIG. Yes. Further, a reverse conveyance path 15 extends along the side surface 1 a in the reverse conveyance unit 14, and the reverse conveyance path 15 is disposed on the side surface 1 a side with respect to the paper conveyance path 10. The reverse conveyance path 15 is for inverting the paper P on which image formation has been performed on one side and conveying the paper P to the image forming unit 4. Each is formed so as to be connected to the upstream side and the downstream side of the sheet conveyance path 10.

  When the paper P is reversely conveyed, when the paper P having an image fixed on one surface is discharged by the discharge roller pair 13 for a predetermined length, the discharge roller pair 13 is reversely driven to switch back. Then, by conveying the paper P toward the reverse conveyance path 15, the front and back of the paper P are reversed and re-conveyed to the image forming unit 4. A branching means is provided at the connecting position of the reverse conveying path 15 and the paper conveying path 10, and the operation of the branching means is controlled by turning on and off a driving mechanism such as a solenoid, whereby the paper P is transferred to the reverse conveying path 15. It is good also as a structure conveyed toward.

  The reversed paper P is guided to the reverse conveyance path 15 and is conveyed again to the upstream area of the paper conveyance path 10 via the conveyance roller pairs 17 to 19. Then, the sheet is conveyed toward the image forming unit 4 through the sheet conveying path 10, the image is formed on the other surface of the sheet P by the image forming unit 4, the transferred image is fixed by the fixing unit 5, and then the discharge roller pair The sheet is discharged to the discharge unit 6 via 13.

  In the present embodiment, a manual paper feed unit 22 for carrying the paper Q into the apparatus main body 2 is provided. The manual paper feed unit 22 includes a manual paper feed tray 23 and a pickup roller 24. . The paper Q placed on the manual paper feed tray 23 is rotated by a pick-up roller 24 so as to prevent the multi-feed of the fed paper Q, and a manual paper feed unit 22. The paper is fed from the manual paper feed tray 23 to the paper transport path 10 through a manual paper feed transport path 27 connecting the paper transport path 10 and the paper transport path 10. The manual paper feed tray 23 is pivotally supported with respect to the apparatus main body 2 so as to be opened and closed.

  Here, the present embodiment is characterized in the arrangement of the paper transport path 10 and the manual paper feed unit 22. That is, as shown in FIG. 1, the sheet conveyance path 10 is placed in the second quadrant and the third quadrant of a rectangular coordinate system with the rotation center of the photosensitive drum 132 provided in the black unit 131B as the origin. And the manual sheet feeding unit 22 is arranged in the fourth quadrant of the rectangular coordinate system.

  With this arrangement, it is not necessary to provide the manual paper feed path 27 at a steep angle with respect to the paper path 10. Therefore, even when thick paper or stiff paper is used as the paper Q, it is possible to effectively suppress the occurrence of jamming and oblique conveyance, and stable paper feeding can be performed.

  In the present embodiment, as shown in FIG. 1, the paper feed unit 3 (or the paper feed cassette 7) is arranged in the third quadrant and the fourth quadrant of the rectangular coordinate system and manually feeds. A conveyance path 27 is disposed above the sheet feeding unit 3 and in the fourth quadrant of the rectangular coordinate system.

  In the conventional image forming apparatus, in order to avoid inconveniences such as a jam, it is necessary to provide a manual feed conveyance path having a sufficient length on the side surface side in the apparatus main body where the sheet conveyance path is provided. Therefore, there is a problem that the apparatus becomes large and the installation width of the image forming apparatus becomes large.

  On the other hand, in the present embodiment, by arranging the paper feed unit 3 and the manual paper feed conveyance path 27 as described above, when the manual paper feed conveyance path 27 is provided in the apparatus main body 2, It is possible to effectively use the empty space 30 of the system. Therefore, it is not necessary to provide the manual paper feed conveyance path 27 on the side surface portion 1a side in the apparatus main body 2 provided with the paper conveyance path 10, and it is possible to avoid an increase in the size of the apparatus.

  As described above, the paper conveyance path 10 is disposed in the second quadrant and the third quadrant of the rectangular coordinate system with the rotation center of the photosensitive drum 132 as the origin, and is manually fed into the fourth quadrant of the rectangular coordinate system. By arranging the unit 22, it is possible to effectively suppress the occurrence of jam and oblique conveyance. However, a jam may occur in the manual paper feed conveyance path 27.

  Therefore, in the present embodiment, as shown in FIG. 1, a manual paper feed conveyance unit 28 having a manual paper feed conveyance path 27 is provided, and the manual paper feed conveyance unit 28 can be opened and closed with respect to the apparatus main body 2. It is set as the structure provided in.

  As an opening / closing mechanism of the manual sheet feeding / conveying unit 28, for example, a guide rail (not shown) is provided in the above-described empty space 30, and a slide rail (not shown) is provided in the manual sheet feeding / conveying unit 28. . Then, the manual sheet feeding / conveying unit 28 is inserted into the empty space 30 of the apparatus main body 2 and the slide rail is engaged with the guide rail so that the manual sheet feeding / conveying unit 28 is moved in the direction of arrow A shown in FIG. When pushed in, the slide rail slides on the guide rail, and the manual sheet feeding / conveying unit 28 can be mounted on the apparatus main body 2 (see FIG. 3 described later). Conversely, by pulling out the manual paper feed conveyance unit 28 in the direction of arrow B shown in FIG. 3 to be described later, the slide rail slides on the guide rail and the manual paper feed conveyance unit 28 is pulled out. (See FIG. 4 described later). In the present embodiment, the same paper feed cassette 7 can be opened and closed (or detachable) with respect to the apparatus body 2 by adopting the same opening / closing mechanism for the paper feed cassette 7 described above. It is configured as follows.

  Further, as shown in FIG. 1, the manual sheet feeding / conveying unit 28 includes the above-described manual sheet feeding / conveying path 27, sheet conveying guide members 28 a and 28 b for guiding conveyance of the sheet Q, and a plurality of conveying roller pairs 29. It is comprised by. Further, the paper transport guide member 28 a is provided so as to be detachable from the manual paper feed transport unit 28.

  Next, jam processing will be described with reference to the drawings. FIG. 3 is an external perspective view showing a state in which the paper feed cassette is opened in the image forming apparatus according to the embodiment of the present invention, and FIG. 4 is a manual feed cassette and manual feed in the image forming apparatus according to the embodiment of the present invention. It is an external appearance perspective view which shows the state which opened the paper feeding conveyance unit. FIG. 5 is an external perspective view showing a state when the jammed paper is removed in the image forming apparatus according to the embodiment of the present invention.

  When the jam processing is performed, first, from the state shown in FIG. 2, the paper feed cassette 7 is pulled out in the direction of arrow B to obtain the state shown in FIG. Next, from the state where the paper feeding cassette 7 is opened as shown in FIG. 3, the manual paper feeding / conveying unit 28 is pulled out in the direction of the arrow B to the state shown in FIG. Then, from the state shown in FIG. 4, by removing the paper transport guide member 28a detachably provided from the manual paper feed transport unit 28 from the manual paper feed transport unit 28, the state shown in FIG. In this state, the jammed paper in the manual paper feed conveyance path 27 is removed.

  As described above, in the present embodiment, the manual sheet feeding / conveying unit 28 having the manual sheet feeding / conveying path 27 is provided to be openable and closable with respect to the apparatus main body 2. Therefore, even when a jam occurs in the manual paper feed path 27, the jam processing can be performed only by opening the manual paper feed unit 28 when processing the jammed paper. The operability when removing the jammed paper is improved, and the jam processing is facilitated.

  In addition, the said embodiment is only an explanatory example, The scope of the present invention is not limited to the said embodiment, Based on the meaning of this invention, the shape, dimension, material, etc. of each component are changed. It is possible that they are not excluded from the scope of the present invention.

  For example, in the above-described embodiment, the description has been given using the tandem color image forming apparatus in which a plurality of image transfer units are arranged along the paper conveyance direction. However, the present invention is an image having only one image forming unit. A configuration applied to the forming apparatus may be employed.

  In the above embodiment, a printer is shown as an example of the image forming apparatus. However, it goes without saying that other image forming apparatuses such as a facsimile and a digital copying machine may be used.

  As an application example of the present invention, it relates to an image forming apparatus such as a copying machine, a printer apparatus, a facsimile apparatus or the like, and particularly includes an image forming apparatus provided with a manual sheet feeding device as a sheet feeding path.

1 is a schematic diagram illustrating an overall configuration of an image forming apparatus according to an embodiment of the present invention. 1 is a perspective view showing an external configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is an external perspective view showing a state in which a paper feed cassette is opened in the image forming apparatus according to the embodiment of the present invention. FIG. 3 is an external perspective view showing a state in which a paper feed cassette and a manual paper feed conveyance unit in the image forming apparatus according to the embodiment of the present invention are opened. 1 is an external perspective view showing a state when removing jammed paper in an image forming apparatus according to an embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 1a ... Side part, 2 ... Apparatus main body, 3 ... Paper feed part, 4 ... Image forming part, 5 ... Fixing part, 6 ... Discharge part, 7 ... Paper feed cassette, 8 ... Paper feed roller, DESCRIPTION OF SYMBOLS 9 ... Paper conveyance part, 10 ... Paper conveyance path, 14 ... Reverse conveyance part, 15 ... Reverse conveyance path, 22 ... Manual feed unit, 23 ... Manual feed tray, 27 ... Manual feed conveyance path, 28 ... Manual feed Paper transport unit, 28a ... paper transport guide member, 28b ... paper transport guide member, 30 ... empty space, 131 ... image transfer unit, 131B ... black unit, 131C ... cyan unit, 131M ... magenta unit, 131Y ... yellow Unit, 132 ... photosensitive drum, P ... paper, Q ... paper

Claims (3)

An image forming unit having an apparatus main body and an image carrier rotatably supported in a predetermined direction, and forming an image on a sheet; the image forming unit disposed upstream of the image forming unit; A paper feed unit that conveys the paper toward the paper, a discharge unit that is disposed on the downstream side of the image forming unit, that forms an image by the image forming unit, and that stores the discharged paper, A sheet conveyance path provided between the sheet feeding unit and the discharge section, a manual sheet feeding unit for carrying the sheet into the apparatus main body, and a manual sheet feeding conveyance path for connecting the manual sheet feeding unit and the sheet conveyance path. In an image forming apparatus comprising:
The sheet conveyance path is disposed in the second quadrant and the third quadrant of the rectangular coordinate system with the rotation center of the image carrier as the origin, and the manual sheet feeding unit is disposed in the fourth quadrant of the rectangular coordinate system. An image forming apparatus.   The sheet feeding unit is disposed in the third quadrant and the fourth quadrant of the rectangular coordinate system, and the manual sheet feeding conveyance path is located above the sheet feeding unit and in the fourth quadrant of the rectangular coordinate system. The image forming apparatus according to claim 1, wherein the image forming apparatus is disposed on the screen.   The manual feed / conveyance unit having the manual feed / conveyance path is provided, and the manual feed / conveyance unit is provided to be openable and closable with respect to the apparatus main body. Item 3. The image forming apparatus according to Item 2.

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