JP2007279168A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of preventing the increase of a cost and the upsizing of the apparatus, and also, capable of enhancing an operation rate. <P>SOLUTION: A plurality of sheet feeding units 4 and 6 are connected in series to the image forming apparatus main body 1 including an image forming part 101, and also, an escape unit 3 having a common conveying path 35 for conveying the sheets fed from the plurality of sheet feed units 4 and 6 and an escape conveying path 31 branching from the common conveying path 35 in order to discharge the sheets is provided on the downstream side of the sheet feed unit 4 arranged on the downmost side among the plurality of sheet feed units 4 and 6, are provided. The abnormality of the sheet passing through the common conveying path 35 is detected by an abnormality detection sensor S, and also, the abnormality-detected sheet is discharged through the escape conveying path 31 based on the detection result by the abnormality detection sensor S. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus in which a plurality of sheet feeding units that store and feed sheets are connected in series to an image forming apparatus main body.

  In recent years, a field called POD (Print On Demand) has attracted attention as a field related to digital copying machines and printing. Here, since this POD can meet the demand for various types and small lots and the contents can be changed, it is suitable for production of documents such as manuals, personal pamphlets and the like.

  An image forming apparatus such as a digital copying machine capable of such on-demand printing has improved in image quality to a level close to a printed matter due to recent high image quality. For this reason, it has come to be used for printing brochures such as catalogs and product manuals, or booklets such as distributions in offices.

  By the way, as an image forming apparatus corresponding to on-demand printing, in order to support various sheets, as shown in FIG. There are things that are connected in series.

  Also, there is a sheet processing apparatus 2002 that performs a folding process, a stapling process, a punching process, a bookbinding process, and the like on a sheet output from the image forming apparatus main body 2000. Further, there is a structure in which a plurality of insert sheet supply units for supplying an insert sheet are provided in series with the sheet processing apparatus 2002 on the downstream side of the image forming apparatus main body 2000.

  The insert sheet refers to a sheet such as a photographic image or a partition sheet that is inserted between sheets on which an image is formed when bookbinding or the like is performed with a sheet on which images are continuously formed in the image forming apparatus main body 2000. .

  By providing the sheet processing apparatus 2002 and the insert sheet supply unit on the downstream side of the image forming apparatus main body 2000 in this way, processing of the sheet on which the image has been formed is performed by a series of job operations.

  By the way, as such an image forming apparatus, there is one in which a plurality of sheet processing apparatuses having different functions are connected to the image forming apparatus main body 2000 so that different processes are continuously performed on sheets. Further, in order to prevent a reduction in operating rate, there is a type in which each sheet processing apparatus is provided with a sub discharge tray.

  If an abnormality such as double feeding or skew feeding of sheets is detected during sheet processing, the sub discharge tray provided in the closest sheet processing apparatus on the upstream side of the sheet processing apparatus that detected the abnormality In addition, double-feed or skewed sheets are discharged (see Patent Document 1).

JP 2005-343661 A

  Here, in such a conventional image forming apparatus, in order to guide the multi-feed or skewed sheet or the like to the sub paper discharge tray of the sheet processing apparatus on the upstream side of the sheet processing apparatus in which the abnormality is detected, It is necessary to provide a sheet conveyance path for discharging in the sheet processing apparatus.

  However, when each sheet processing apparatus is provided with a sheet conveying path for discharge in this way, the number of sheet conveying paths increases, and as a result, jamming occurs not only in the sheet conveying path but also in the branching section. As a result, it becomes difficult to convey the sheet stably. Note that this is not limited to the sheet processing apparatus, and if the paper feed decks 2001 connected in cascade are configured in the same manner, there is a high possibility that a jam will occur in the sheet conveyance path or branching section. It becomes difficult to convey the sheet stably.

  Further, as the number of sheet conveying paths for discharge increases in this way, the number of parts increases and the product cost increases, and the entire apparatus increases in size. Furthermore, since the multi-feed and skewed sheets discharged from the discharge sheet conveying path are discharged to separate sheet processing apparatuses or sheet feeding decks 2001, it takes time to collect the sheets. there were.

  Therefore, the present invention has been made in view of such a situation, and an object thereof is to provide an image forming apparatus capable of preventing an increase in cost and an increase in size of the apparatus and improving an operating rate. To do.

  The present invention includes an image forming apparatus main body including an image forming unit that forms an image on a sheet, a plurality of sheet feeding units that are connected in series to the image forming apparatus main body and feed a stored sheet, A common conveyance path that is connected to a downstream side of the sheet feeding unit disposed at the most downstream of the plurality of sheet feeding units and that conveys the sheet from the plurality of sheet feeding units, and for discharging the sheet An escape unit having an escape conveyance path branched from the common conveyance path, and an abnormality detection sensor for detecting an abnormality of a sheet passing through the common conveyance path, and an abnormality is detected based on the detection of the abnormality detection sensor. The discharged sheet is discharged from the escape conveyance path.

  As in the present invention, an escape unit that discharges a sheet in which an abnormality is detected is provided on the downstream side of the sheet feeding unit that is arranged on the most downstream side among the plurality of sheet feeding units connected to the image forming apparatus main body. Thus, an increase in cost and an increase in size of the apparatus can be prevented. Furthermore, the utilization rate can be improved.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a schematic configuration of an image forming apparatus according to an embodiment of the present invention.

  In FIG. 1, 1A is an image forming apparatus, 1 is an image forming apparatus main body constituting the image forming apparatus 1A, and a first sheet feeding unit 4 and a second sheet feeding are provided on one side of the image forming apparatus main body 1. The unit 6 is connected in series (double connection). Further, an escape unit 3 described later is connected between the image forming apparatus main body 1 and the first sheet feeding unit 4.

  Further, between the first sheet feeding unit 4 and the second sheet feeding unit 6, there is a delivery unit 5 for delivering the sheet from the second sheet feeding unit 6 to the first sheet feeding unit 4. It is connected.

  The other side of the image forming apparatus main body 1 is connected to a sheet processing apparatus 7 that performs a folding process, a stapling process, a punching process, a bookbinding process, and the like on the sheet output from the image forming apparatus main body 1. .

  Here, the image forming apparatus main body 1 includes an electrophotographic image forming unit 101 including a photosensitive drum 103 and the like. In addition, sheet feeding decks 109 and 111 which are sheet storage units for storing sheets, and sheet feeding units 113 and 115 for feeding sheets stored in the sheet feeding decks 109 and 111 are provided. A registration roller 119 for correcting the skew of the sheet and aligning the toner image on the photosensitive drum 103 and the sheet is disposed on the upstream side of the image forming unit 101.

  When the image forming operation is started in the image forming apparatus main body 1 having such a configuration, the image forming unit 101 forms a toner image on the photosensitive drum 103 by an exposure unit, a development unit, and the like (not shown).

  The sheets stored in the sheet feeding decks 109 and 111 are conveyed to the registration rollers 119 via the sheet conveying path 117 by the sheet feeding units 113 and 115. Thereafter, after the skew is corrected by the registration roller 119, the sheet is conveyed between the photosensitive drum 103 and the transfer roller 105 at a predetermined timing.

  As a result, the toner image formed on the photosensitive drum 103 is transferred to the sheet with the transfer roller 105, and then the sheet is heated and pressed by the fixing roller pair 107 to fix the toner image on the sheet. The sheet on which the toner image is fixed in this manner is discharged from the image forming apparatus main body 1 to the sheet processing apparatus 7 by the discharge roller 120, and predetermined processing such as stapling and bookbinding is performed in the sheet processing apparatus 7.

  On the other hand, the first sheet feeding unit 4 includes first to third sheet feeding decks 40, 41, and 42, which are sheet storage units for storing sheets. Further, the first sheet feeding unit 4 feeds the sheets stored in the first to third sheet feeding decks 40, 41, and 42, for example, first to third sheet feeding units of an air feeding type. It has sending parts 43, 44, and 45A.

  Here, the first to third sheet feeding units 43, 44, and 45A are selectively driven based on a signal from a control device C to be described later, and the first to third sheet feeding decks 40, 41, and 42 are driven. The sheets stored in are respectively sent out toward the escape unit 3. The sheet sent out in this way is then conveyed to the image forming unit 101 via the escape unit 3.

  In FIG. 1, reference numeral 45 denotes a first common transport path disposed horizontally between the first paper feed deck 40 and the second paper feed deck 41. The first common transport path 45 is connected to the second common transport path 35 of the escape unit 3 and the third common transport path 55 of the delivery unit 5.

  The first common conveyance path 45 is connected to first to third sheet conveyance paths 46, 47, and 48 for conveying sheets from the first to third sheet feeding decks 40, 41, and 42. In the third sheet conveyance paths 46, 47, 48, conveyance roller pairs 49 are arranged at predetermined intervals. Then, after the sheets from the first to third sheet feeding units 43, 44, and 45 are conveyed along the first to third sheet conveyance paths 46, 47, and 48 by the conveyance roller pair 49, the first It is conveyed to the common conveyance path 45.

  The second sheet feeding unit 6 has the same configuration as the first sheet feeding unit 4. That is, the air for feeding sheets from the fourth to sixth sheet feeding decks 60, 61, 62 and the fourth to sixth sheet feeding decks 60, 61, 62, which are sheet storage units for storing sheets, respectively. The fourth to sixth sheet feeding units 63, 64, and 65A of the sheet feeding method are provided.

  Here, the fourth to sixth sheet feeding units 63, 64, 65A are selectively driven based on a signal from the control device C, and are stored in the fourth to sixth sheet feeding decks 60, 61, 62. Each sheet is sent out toward the delivery unit 5. The sheet fed in this way is then conveyed to the image forming unit 101 via the delivery unit 5, the first sheet feeding unit 4, and the escape unit 3.

  A fourth common transport path 65 is horizontally disposed between the fourth paper feed deck 60 and the fifth paper feed deck 61, and the fourth common transport path 65 is the third common transport path of the delivery unit 5. It is connected to the path 55. Accordingly, the second common conveyance path 35 of the escape unit 3, the first common conveyance path 45 of the first sheet feeding unit 4, the third common conveyance path 55 of the third delivery unit 5, and the second sheet feeding unit 6. The 4th common conveyance path 65 is horizontally arranged on a straight line, and a horizontal conveyance path is constituted.

  In the fourth common conveyance path 65 of the second sheet feeding unit 6, fourth to sixth sheet conveyance paths 66, 67, 68 for guiding sheets from the fourth to sixth sheet feeding decks 60, 61, 62 are provided. Is connected. Further, a pair of conveying rollers 69 is arranged in the fourth to sixth sheet conveying paths 66, 67, 68 at a predetermined interval.

  Then, the sheet from the fourth to sixth sheet feeding units 63, 64, 65 is conveyed along the fourth to sixth sheet conveying paths 66, 67, 68 by the conveying roller pair 69, and then the fourth. It is conveyed to the third common conveyance path 55 of the delivery unit 5 through the common conveyance path 65. The delivery unit 5 is provided with a sheet conveyance roller pair 51 for conveying the sheet along the third common conveyance path 55.

  The escape unit 3 includes an escape conveyance path 31 that branches off from the second common conveyance path 35 and guides the sheet by making a U-turn to the escape tray 33 disposed on the top of the first sheet feeding unit 4. Yes. In the escape conveyance path 31, conveyance roller pairs 32 for conveying the sheet are arranged at a predetermined interval.

  Further, a flapper 36 for selectively allowing the sheet to enter the escape conveyance path 31 is provided at a branch point between the escape conveyance path 31 and the second common conveyance path 35.

  On the other hand, a multi-feed detection sensor S is disposed in the first common transport path 45, and the double-feed detection sensor S allows the second sheet feeding unit 6 and the first to third paper feeding decks 40, 41, 42. An abnormal conveyance state such as double feeding of the sheet conveyed from is detected. The double feed detection sensor S, which is an abnormality detection sensor, may detect not only the double feed of the sheet but also that the sheet is skewed to the extent that the registration roller 119 cannot correct it.

  Here, in FIG. 1, C is a control device, and a signal from the double feed detection sensor S is input to the control device C. When the double feed detection sensor S detects the double feed of the sheet, the control device C is provided with a flapper shown in FIG. 2 provided at a branch point between the second common transport path 35 and the escape transport path 31. 36 is switched to the escape conveyance path 31 side. Thereby, the double-fed sheets are directed to the escape conveyance path 31 of the escape unit 3, and are then discharged to the escape tray 33.

  Further, based on the signal from the control device C, the sheet feeding units 113, 115, 43, 44, 45A, 63, 64, 65A, the conveying roller pairs 32, 49, 69, and the like are appropriately driven.

  By the way, in the present embodiment, the escape unit 3 is arranged only on the downstream side of the most downstream first sheet feeding unit 4 among the first and second sheet feeding units 4 and 6 that are connected in series. Has been.

  Next, an image forming operation in the image forming apparatus 1A having such a configuration will be described.

  First, one of the first to sixth sheet feeding decks 40, 41, 42, 60, 61, 62 of the first and second sheet feeding units 4, 6 is fed by a sheet feeding signal from the control device C. A paper deck is selected. In addition, among the first to sixth sheet feeding units 43, 44, 45A, 63, 64, and 65A, one sheet feeding unit corresponding thereto is driven to feed the sheet.

  For example, when the third sheet feeding deck 42 is selected, the sheet stored in the third sheet feeding deck 42 is sent out by the third sheet feeding unit 45A, and the sheet conveying roller 48 passes through the sheet conveying path 48. The pair 49 is sent to the first common transport path 45. Thereafter, the sheet is sent to the image forming unit 101 of the image forming apparatus main body 1 through the first common transport path 45 and the second common transport path 35 of the escape unit 3 to form an image.

  By the way, when the sheet sent out from the selected paper feed deck is double fed, the first common transport path through which the upstream sheet of the escape unit 3 always passes regardless of the paper feed deck sent out. Double feed is detected by the double feed detection sensor S arranged at 45.

  When the double feed detection sensor S detects the double feed of the sheet in this way, the control device C switches the flapper 36 of the escape unit 3 to the escape conveyance path 31 side indicated by a broken line. As a result, the double-fed sheets are conveyed to the escape conveyance path 31 side and discharged to the escape tray 33. As a result, it is possible to discharge the fed sheets without sending them to the image forming unit 101.

  As described above, the second sheet feeding unit is provided by providing the escape unit 3 on the downstream side of the first sheet feeding unit 4 arranged on the most downstream side of the two (plurality) of sheet feeding units 4 and 6. 6 does not require the escape unit 3 to be arranged. For this reason, it is possible to reduce the number of escape conveyance paths 31 for discharging a sheet in which an abnormality such as double feeding is detected, thereby reducing the occurrence of a jam or the like, increasing the cost, and increasing the size of the apparatus. This can be prevented and the operating rate can be improved.

  Further, since sheets in which an abnormality such as double feeding is detected are collected in one place on the escape tray 33 without being dispersed, processing of the sheet in which the abnormality is detected becomes easy.

  In the present embodiment, the image forming apparatus (image forming system) in which the two sheet feeding units 4 and 6 are connected to the image forming apparatus main body 1 has been described, but three or more sheets are provided in the image forming apparatus main body 1. It is also possible to connect a feeding unit. Even when three or more sheet feeding units are connected in this way, the same effect can be obtained by arranging the escape unit 3 on the downstream side of the sheet feeding unit arranged on the most downstream side. Can do.

  In the present embodiment, sheet feeding units 4 and 6 for feeding sheets to the image forming apparatus main body 1 are disposed upstream of the image forming apparatus main body 1, and the sheet feeding units 4 and 6 are disposed. The configuration in which an abnormality such as double feeding in the printer is detected and discharged to the escape tray 33 has been described. However, the present invention is not limited to this. For example, the present invention can be applied to a case where a plurality of insert paper supply units for supplying insert sheets as a sheet feeding unit are connected to the downstream side of the image forming apparatus main body 1 as a sheet feeding unit.

  In the image forming apparatus configured as described above, the escape unit is connected only to the downstream side of the most downstream insert paper supply unit of the plurality of insert paper supply units. Thereby, the same effect can be acquired.

1 is a diagram illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 4 is a diagram illustrating a configuration of a first sheet feeding unit provided in the image forming apparatus. 1 is a diagram illustrating a schematic configuration of a conventional image forming apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus main body 1A Image forming apparatus 3 Escape unit 4 First sheet feeding unit 6 Second sheet feeding unit 31 Escape conveyance path 33 Escape tray 35 Second common conveyance path 36 Flappers 40, 41, 42 First to second 3 sheet feeding decks 43, 44, 45A 1st to 3rd sheet feeding unit 45 1st common conveyance path 60, 61, 62 4th to 6th sheet feeding decks 63, 64, 65A 4th to 6th sheet feeding Part 101 Image forming part C Control device S Double feed detection sensor

Claims (6)

An image forming apparatus main body including an image forming unit for forming an image on a sheet;
A plurality of sheet feeding units connected in series to the main body of the image forming apparatus and feeding sheets stored therein;
A common conveyance path that is connected to a downstream side of the sheet feeding unit disposed at the most downstream of the plurality of sheet feeding units and that conveys the sheet from the plurality of sheet feeding units, and for discharging the sheet An escape unit with an escape conveyance path branched from the common conveyance path;
An abnormality detection sensor for detecting an abnormality of the sheet passing through the common conveyance path,
An image forming apparatus, wherein a sheet in which an abnormality is detected is discharged from the escape conveyance path based on detection by the abnormality detection sensor.   The abnormality detection sensor is provided in a common conveyance path of the escape unit, and an escape tray from which the sheet in which the abnormality is detected is discharged from the escape conveyance path is provided in an upper part of the sheet feeding unit arranged on the most downstream side. The image forming apparatus according to claim 1. Each of the plurality of sheet feeding units includes a plurality of sheet storage units, and a common conveyance path through which the sheets fed from the plurality of sheet storage units pass,
The common transport path of the plurality of sheet feeding units is connected to form a horizontal transport path, and the horizontal transport path and the common transport path of the escape unit are connected horizontally. Item 3. The image forming apparatus according to Item 1 or 2.   The flapper which selectively makes the sheet | seat in which the said abnormality was detected go to the said escape conveyance path at the branch point of the common conveyance path of the said escape unit, and the said escape conveyance path, The Claim 1 thru | or 3 characterized by the above-mentioned. The image forming apparatus according to claim 1.   5. The plurality of sheet feeding units are connected in series via the escape unit to the upstream side of the image forming apparatus main body, and feed sheets to the image forming apparatus main body. The image forming apparatus according to any one of the above. The plurality of sheet feeding units are connected in series to the downstream side of the image forming apparatus main body, and insert sheets between sheets after image formation conveyed from the image forming apparatus main body. The image forming apparatus according to any one of claims 1 to 4.

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