JP2006213507A - Image forming system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming system improved in productivity by arranging a sheet postprocessing device between a sheet feeding device and an image forming device. <P>SOLUTION: The image forming system 30 comprises the image forming device 1 forming an image, the sheet feeding device 3 feeding sheets to the image forming device 1, and the sheet postprocessing device 2 performing postprocessing to the sheet on which the image is formed. The sheet postprocessing device 2 is arranged between the image forming device 1 and the sheet feeding device 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention includes a sheet supply device, an image forming device, and a sheet post-processing device, and an image forming method in which the sheet post-processing device is disposed between the sheet supply device and the image forming device to improve productivity. It is about the system.

  2. Description of the Related Art Conventionally, there is an image forming system formed by connecting an image forming apparatus that forms an image on a sheet and a sheet post-processing apparatus that performs post-processing on an image-formed sheet discharged from the image forming apparatus (Patent Document). 1).

  In recent years, there has been an increasing demand for such an image forming system to improve the productivity of the entire image forming system, including not only the speed at which an image is formed on a sheet but also the post-processing of the sheet and the work of an operator. ing.

  A conventional image forming system 600 shown in FIG. 3 includes a sheet feeding device (hereinafter, “ The paper deck is called “paper deck” 603.

  The image forming apparatus 601 includes an image reader unit 200 and a printer 300. The sheet post-processing device 602 includes a folding device 400 and a finisher main body 500.

  The document image read by the image reader unit 200 is subjected to image processing and sent to the exposure control unit 110. The exposure control unit 110 irradiates the photosensitive drum 111 with laser light corresponding to the image signal. An electrostatic latent image is formed on the photosensitive drum 111 where the laser beam is irradiated. The electrostatic latent image is developed with toner by the developing device 113 and visualized as a toner image.

  On the other hand, the sheet fed from any of the cassettes 114 and 115, the manual sheet feeding unit 125, the duplex conveyance path 124, and the paper deck 3 passes through the conveyance roller pair 131 to the stopped registration roller pair 126. The leading edge hits the nip of the roller pair and temporarily stops. Thereafter, the registration roller pair 126 takes a timing to align the position with the toner image on the photosensitive drum 111, starts to rotate, and feeds the sheet between the photosensitive drum 111 and the transfer device 116. The transfer device 116 transfers the toner image on the photosensitive drum 111 to a sheet.

  The toner image is permanently fixed by the fixing device 117 on the sheet on which the toner image is transferred. The sheet that has passed through the fixing device 117 is once guided to the path 122 by the flapper 121, and after the trailing end passes through the flapper 121, is switched back and is guided to the flapper 121 again to the discharge roller pair 118. It is burned. As a result, the sheet is discharged from the printer 300 by the discharge roller pair 118 with the surface onto which the toner image is transferred facing down (face down). This is called reverse paper discharge. By discharging the sheet face down, the sheet can be printed on the correct page when forming an image in order from the first page, such as when using the document feeder 100 or when printing an image output from a computer. In order.

  Note that a hard sheet such as an OHP sheet is manually fed from the manual sheet feeding unit 125 and is not guided to the path 122, and the surface onto which the toner image is transferred is faced up from the discharge roller pair 118. Discharged. In addition, the sheet for image formation on both sides is guided straight from the fixing device 117 to the discharge roller pair 118, and immediately after the trailing edge passes through the flapper 121, is switched back and passed by the guidance of the flapper 121. 122 is guided to the double-sided conveyance path 124.

  The sheet discharged from the discharge roller pair 118 is sent to the folding device 400. The folding device 400 performs a process of folding the sheet into a Z shape. A sheet that is designated for folding processing in A3 size or B4 size is subjected to folding processing by the folding device 400. The other sheets are sent to the finisher main body 500 as they are. The finisher main body 500 performs post-processing such as bookbinding, binding, and punching by the bookbinding unit 800. In addition, an inserter 900 is provided on the upper portion of the finisher body 500. The inserter 900 is configured to send a cover sheet, a slip sheet, and the like to the finisher body 500.

  In recent years, there is an increasing demand for the image forming system 600 to improve productivity (= number of image prints per hour). Accordingly, it is conceivable to increase the sheet conveyance speed of the image forming process unit 604 from the photosensitive drum 111 to the fixing device 117. However, when the sheet conveying speed is increased, the operation load of the image forming apparatus 601 and the fixing device 117 increases, and the operations thereof become unstable and the image quality may be deteriorated. Therefore, in recent image forming systems, instead of suppressing the sheet conveyance speed of the image forming process unit 604 as much as possible, productivity is improved by shortening the sheet interval in the printer 300 such as exposure, development, transfer, and fixing as much as possible.

  However, in the conventional image forming apparatus system 600, when the sheet interval is shortened, the next succeeding sheet catches up while the preceding sheet is temporarily stopped by the registration roller pair 126. In the above-described reverse discharge, when the preceding sheet passes through the fixing device 117 and is once guided to the conveyance path 122 by the flapper 121, before the trailing edge of the preceding sheet exits the flapper 121, the next succeeding sheet is detected. The sheet reaches the flapper 121, and the succeeding sheet catches up with the preceding sheet. In this way, catching up with the succeeding sheet after the preceding sheet causes a jam.

  Therefore, in order to prevent the succeeding sheet from catching up with the preceding sheet, the sheet conveying speed in the pair of conveying rollers 131, 132, 133, and 134 other than the image forming process unit 604 is increased to widen the sheet interval. Can be considered.

  That is, the conveyance roller pair 131, 132, 133 conveys the sheet from the cassette 114, 115, the paper deck 603, etc. to the registration roller pair 126 at a sheet conveyance speed faster than the sheet conveyance speed of the image forming process unit. Then, the registration roller pair 126 takes the supply timing of the sheet to the photosensitive drum 111 and conveys the sheet to the photosensitive drum 111 and the transfer device 116 at a sheet conveying speed of the image forming process unit 204. Further, the conveying roller pair 134 and the like increase the sheet conveying speed again when the trailing edge of the sheet passes through the fixing device 117, and at a sheet conveying speed at which the subsequent sheet cannot catch up at the time of reverse discharge. Transport.

  The above image forming system forms a black and white image. However, in recent years, a full color image forming system using an image forming apparatus that forms a full color image on the image forming apparatus has been widely used. Yes. This full-color image forming system has a tendency to increase the speed, functionality, reliability, and capacity of each device as productivity increases (not a feature limited to full color). For this reason, the image forming apparatus, the sheet supply apparatus, and the like become large, and the length of the entire system may be several meters. Such a full-color image forming system is generally used for business such as copying and printing.

  Note that the overall length of the system is not limited to the full-color image forming system. Also in the image forming system 600 that forms a black and white image on a sheet, the productivity tends to increase as the productivity increases.

JP 2000-21803 A

  However, the conventional image forming system has the following problems.

  That is, in order to increase the productivity, when changing the sheet conveyance speed, it is necessary for each roller pair for sheet conveyance to repeat stop, acceleration, deceleration, steady rotation of multiple speeds, reverse rotation, and the like. Stepping motors are often used to achieve this.

  The stepping motor will step out when it accelerates or decelerates rapidly. For this reason, the stepping motor requires a certain amount of acceleration / deceleration time. The acceleration / deceleration time is determined by how much the sheet interval increase rate in the sheet conveying unit is set with respect to the sheet interval in the image forming apparatus. The larger the ratio, the longer the acceleration / deceleration time.

  On the other hand, the seat is moving during acceleration / deceleration. If the sheet conveyance path is too short, sufficient acceleration / deceleration time cannot be obtained. In order to solve this problem, you can choose between using a more powerful motor and accelerating or decelerating in a short time, or making the conveyance path long enough to increase the acceleration / deceleration time. become. Even if it solves by any method, it becomes factors, such as an increase in apparatus cost, an increase in power consumption, and an enlargement of an apparatus. Further, if neither of them can be selected, the sheet interval in the image forming process unit 604 has to be made wider than a desired value to sacrifice image quality.

  There are also problems from the following viewpoints.

  That is, an image forming system used for business such as copying and printing requires an operator to perform a large amount of printing work in as short a time as possible. For this reason, it is necessary not only to improve the productivity of the image forming system itself, but also to make the image forming system easy to work for the operator.

  However, the image forming system 600 shown in FIG. 3 includes a large-capacity sheet feeding device 603 and a sheet post-processing device 602 on both sides of the image forming device 601. Further, an apparatus operation unit (not shown) of the image forming system and the image reader unit 200 are also arranged in the center of the system. For this reason, when the entire image forming system becomes longer, a position where a new sheet is replenished to the sheet feeding device 603, a position where the entire system is operated, a post-processed sheet (a sheet that has been bound, a folding process, and a punch process) For example, a position where a sheet to be inserted is taken out, a position where a sheet to be inserted into the inserter 900 is installed, and the like, the movement distance when the operator works is long and the work range is wide. As a result, the operator's work efficiency was poor.

  Recently, the image reader unit 200 can be separately placed on a side desk or the like, or a general-purpose personal computer is connected to the image forming system 601 and the apparatus is operated from the personal computer. There are things that can be done. In this case, the work efficiency of the operator is slightly improved, but on the other hand, there is a problem that the exclusive area of the entire image forming system increases.

  An object of the present invention is to provide an image forming system in which a sheet post-processing apparatus is disposed between a sheet supply apparatus and an image forming apparatus to improve productivity.

  In order to achieve the above object, an image forming system of the present invention includes an image forming apparatus that forms an image on a sheet, a sheet supply device that supplies the sheet to the image forming apparatus, and post-processing the sheet on which the image is formed. The sheet post-processing apparatus is provided, and the sheet post-processing apparatus is disposed between the image forming apparatus and the sheet supply apparatus.

  In the image forming system of the present invention, since the sheet feeding device and the sheet post-processing device are arranged next to each other, a position where a new sheet is replenished to the sheet feeding device, the post-processed sheet is transferred from the sheet post-processing device. The positions to be taken out approach each other, the moving distance when the operator works is shortened, and the working range of the operator can be narrowed. As a result, the image forming system of the present invention can improve the work efficiency of the operator and increase the productivity.

  Hereinafter, an image forming system according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. The same parts as those in the prior art will be described with the same reference numerals.

  FIG. 1 is a schematic cross-sectional view along the sheet conveying direction of an image forming system according to an embodiment of the present invention. The image forming system 30 includes an image forming apparatus 1, a sheet post-processing apparatus 2, a sheet feeding apparatus 3 (hereinafter referred to as “paper deck”), and an image reading apparatus 4, and forms an image on a sheet. Post-processing is performed. A sheet post-processing apparatus 2 is disposed between the sheet supply apparatus 3 and the image forming apparatus 1.

  The image reading device 4 is not necessarily required. An image may be formed on the sheet in response to an image information signal from the outside. The image forming system of the present embodiment forms a toner image on a sheet, but it may be a printer that forms an image on a sheet by ejecting ink from an inkjet.

  The entire image forming system 30 is controlled by a control unit 33 provided in the image forming apparatus 1. The control unit 33 is not limited to the image forming apparatus 1 and may be provided in another place.

  The image forming apparatus 1 includes an exposure control unit 110, a photosensitive drum 111, a developing unit 113, a transfer unit 116, a fixing unit 117 as a fixing unit, a discharge roller pair 118, a flapper 121, a conveyance path 122, a duplex conveyance path 124, and a rotation. A registration roller pair 126 as a body pair is provided.

  The sheet post-processing apparatus 2 includes a folding device 400 and a finisher main body 500.

  The paper deck 3 includes a plurality of sheet storage units 31 and 32 (two in this example), a feeding roller group 11 and 12 and the like, and stores a large amount of sheets and supplies them to the image forming apparatus 1. It can be done.

  The image reading device 4 is provided on the paper deck 3. The image reading device 4 includes a document feeder 100, a platen glass 102, a lamp 103, a scanner unit 104, mirrors 105, 106, and 107, a lens 108, an image sensor 109, a paper discharge tray 112, and the like.

  The finisher body 500 includes a stack tray 700 for stacking sheets that have been post-processed such as staples and punches, a sample tray 701 for stacking sheets that are not post-processed and sheets that are output as samples, a bookbinding unit 800, and a bookbinding unit. A tray 702 on which a bundle of sheets bound in 800 is stacked, an inserter 900, and the like are provided.

  From the sheet storage unit 31 (or 32) by the feeding roller group 11 (or 12) by the conveyance paths 13 and 16 as the supply guide path and a plurality of conveyance roller groups 15 provided along the conveyance paths 13 and 16. The fed sheet is guided and conveyed to the image forming apparatus 1. The conveyance path 13 is a part of the conveyance path that passes under the sheet post-processing apparatus 2 and reaches the image forming apparatus 1. A sensor 14 is provided in the transport path 13. The sensor 14 can detect the positions of the leading edge and the trailing edge of the sheet. When the trailing edge of the sheet passes through the sensor 14, the conveying roller group 15 starts to rotate at an accelerated speed and reaches a steady rotational speed after a predetermined acceleration time. During this time, the sheet reaches the conveyance path 16.

  A sensor 17 is provided in the transport path 16. The sensor 17 detects the arrival of the sheet front end. When the leading edge of the sheet is detected by the sensor 17, the transport roller group 18 disposed on the downstream side of the transport path 16 starts decelerating rotation. The downstream end of the conveyance path 16 extends to the registration roller pair 126.

  A sensor 19 is provided immediately before the registration roller pair 126. The sensor 19 detects that the leading edge of the sheet has surely reached the nip of the registration roller 126. When the sheet reaches the sensor 19 while decelerating, the registration roller pair 126 stops rotating. The sheet abuts against the nip of the registration roller pair 126 whose rotation is stopped to form a loop, and then temporarily stops. Then, the registration roller pair 126 restarts in synchronization with a toner image formed on the photosensitive drum 111 described later.

  In the image forming system 30 of the present embodiment, when the sheet of the maximum imageable length is temporarily stopped after the loop is formed by the registration roller pair 126, the trailing edge of the sheet is substantially the same as that in FIG. It stops at the position indicated by the broken line A. For this reason, the conveyance roller group 18 must be stopped while the sheet is stopped. When the sheet is continuously conveyed, the control unit 33 determines the speed increase rate of the conveyance roller group 15 so that the subsequent sheet does not enter the stopped conveyance roller group 18, and sets the necessary sheet interval. Secured.

  On the other hand, the document image read by the image reader unit 200 is subjected to image processing and sent to the exposure control unit 110. The exposure control unit 110 irradiates the photosensitive drum 111 with laser light corresponding to the image signal. An electrostatic latent image is formed on the photosensitive drum 111 where the laser beam is irradiated. The electrostatic latent image is developed with toner by the developing device 113 and visualized as a toner image.

  The sheet is fed between the photosensitive drum 111 and the transfer unit 116 by the above restart of the registration roller pair 126 in time with the toner image formed on the photosensitive drum 111. The transfer device 116 transfers the toner image on the photosensitive drum 111 to a sheet. Then, the fixing device 117 fixes the toner image on the sheet. The sheet reaches the flapper 121. In the case of duplex image formation, the sheet is guided to the conveyance path 122. When the trailing edge of the sheet passes through the flapper 20, the roller pair 21 is reversed. At the same time, the flapper 20 is switched. As a result, the sheet is switched back and sent to the duplex conveying path 124, and a toner image is formed on the other surface. In the transfer device 116, a portion that transfers an image to a sheet such as the photosensitive drum 111 constitutes an image forming unit.

  A case where the sheet is conveyed to the sheet post-processing apparatus 2 will be described.

  The flapper 121 guides the sheet in the horizontal direction and guides the sheet to the transport path 25 as a processing guide path. On the other hand, a sensor 26 that detects a sheet is provided on the downstream side of the fixing device 117 in the sheet conveyance direction. When the trailing edge of the sheet passes through the sensor 26, the transport roller group 23 starts rotating at an increased speed. The sheet is accelerated by the sheet post-processing apparatus 2 until a sheet interval necessary for various processes such as sheet alignment is reached, and then sent to the sheet post-processing apparatus 2 at a steady conveyance speed. The sheet post-processing apparatus 2 performs various processes on the sheet as in the conventional example, and then discharges the sheet to one of the three trays 700, 701, and 702. The sheets are stacked on the discharged tray.

  FIG. 2 is a partial external perspective view of the image forming system 30 shown in FIG.

  An image reading device 4 is installed on the paper deck 3, and an operation unit 5 that controls the entire image forming system 30 is installed on the operator side (front) of the image reading device 4. A take-out door 27 is provided in front of the sheet post-processing apparatus 2 so that a sheet processed by the sheet post-processing apparatus 2 can be taken out from the front. A rotation hinge 28 as a hinge portion of the take-out door 27 is provided on the side far from the paper deck 3 (left side in FIG. 2), and is loaded on the stack tray 700, the sample tray 701, and the tray 702 from the paper deck 3 side. It is easy to take out the used sheet.

  The image forming system 30 having the above-described configuration is a part of the entire image forming system 300 that is accessed when an operator performs normal work, such as the image reading device 4, the operation unit 5, the take-out door 27 of the sheet post-processing device 2, and the inserter 900. They are collectively provided on one side (in the present embodiment, the right side). For this reason, the operator can work in a small work range regardless of the length and size of the image forming system 30. Accordingly, the work efficiency of the image forming system 30 as a whole is significantly improved.

  Further, since the image forming system 30 has the conveyance path 13 for guiding the sheet from the paper deck 3 to the photosensitive drum 111 below the sheet post-processing apparatus 2, the sheet post-processing apparatus 2 is substantially longer than the conventional one. Accordingly, the length of the conveyance path 13 can be increased, and an acceleration distance sufficiently necessary for accelerating the sheet can be obtained. As a result, the image forming system can easily manage the sheet speed without increasing the overall length, and can improve productivity. In addition, it is not necessary to rapidly accelerate or decelerate a stepping motor (not shown) that rotates the transport roller group 15 and the like, and motor step-out can be prevented. Further, it is possible to prevent the motor from becoming large and to reduce the cost of the image forming system 30. Power consumption can be reduced and economic efficiency can be improved.

  Further, when the image forming system 30 conveys the image-formed sheet to the sheet post-processing apparatus 2, the image forming system 30 passes the conveyance path 25 provided in the upper part of the image forming apparatus 1. The sheet can be naturally conveyed to the sheet post-processing apparatus 2 in the face-down state without performing the reverse of the sheet by the switch-back conveyance that realizes the face-down discharge that has been conventionally performed.

  Therefore, the image forming system 30 of this embodiment can obtain a sufficiently long acceleration distance without enlarging the entire image forming system. In addition, the subsequent sheet does not catch up during the switchback reversal described in the conventional example, and the sheet can be accelerated until the sheet interval required by the sheet post-processing apparatus 2 is reached. As a result, the image forming system 30 can easily manage the sheet speed and improve the productivity.

  In addition, when the transport path 25 is provided in the state where the image reader unit 200 and the operation unit are installed at the upper portion as in the image forming apparatus 601 illustrated in FIG. 3, the height of the image forming system is increased. In the image forming system 30 according to the embodiment, since the conveyance path 25 is provided on the upper part of the image forming apparatus 1 in which the image reading device 4 and the operation unit 5 are not provided, the height can be reduced.

  In the image forming system 30 shown in FIG. 1, since the inserter 900 is installed above the sheet folding device 400 and the finisher body 500, the document feeder 100, the image reader unit 200, And the operation part 5 is installed. However, in the case of a large-capacity sheet folding device 400 without the inserter 900 and the finisher main body 500, the image reader unit 200, the document feeding device 100, and the operation unit 5 can be installed on the top thereof. In this case, since nothing is provided at the top of the paper deck 3, there is no height restriction, and the number of sheets stored in the paper deck 3 and the number and types of sheet storage sections can be increased.

1 is a schematic cross-sectional view along the sheet conveying direction of an image forming system according to an embodiment of the present invention. FIG. 2 is a partial external perspective view of the image forming system shown in FIG. 1. FIG. 10 is a schematic cross-sectional view along a sheet conveying direction of a conventional image forming system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Sheet post-processing apparatus 3 Sheet supply apparatus 4 Image reading apparatus 5 Operation part 13 Conveyance path (supply guide path)
16 Transport pass (supply guide pass)
25 Transport pass (processing guide pass)
27 Removal door 28 Rotating hinge (hinge)
DESCRIPTION OF SYMBOLS 30 Image forming system 31 Sheet storage part 32 Sheet storage part 33 Control part 100 Document feeder 111 Photosensitive drum (image formation means)
116 Transfer device (image forming means)
117 Fixing device (fixing means)
121 Flapper 122 Conveying path 126 Registration roller pair (rotating body pair)
200 Image reader unit 400 Folding device 500 Finisher body 700 Stack tray 701 Sample tray 702 Tray 800 Bookbinding unit 900 Inserter

Claims (7)

An image forming apparatus for forming an image on a sheet;
A sheet supply device for supplying a sheet to the image forming apparatus;
A sheet post-processing device that performs post-processing on the sheet on which the image is formed,
An image forming system, wherein the sheet post-processing apparatus is disposed between the image forming apparatus and the sheet supply apparatus.   The image forming system according to claim 1, wherein a supply guide path for guiding a sheet from the sheet supply apparatus to the image forming apparatus is provided below the sheet post-processing apparatus.   The image forming system according to claim 1, wherein a processing guide path for guiding a sheet from the image forming apparatus to the sheet post-processing apparatus is provided in an upper part of the image forming apparatus. Image forming means having image forming means for transferring a toner image to a sheet, a pair of rotating bodies for conveying the sheet to the image forming means upstream of the image forming means in the sheet conveying direction, and a fixing means for fixing the toner image to the sheet Equipment,
A sheet supply device for supplying a sheet to the image forming apparatus;
A sheet post-processing apparatus disposed between the image forming apparatus that performs post-processing on a sheet on which an image is formed and the sheet supply apparatus;
A supply guide path provided below the sheet post-processing apparatus for guiding the sheet from the sheet supply apparatus to the rotating body pair;
A processing guide path provided at an upper part of the image forming apparatus for guiding a sheet from the fixing unit to the sheet post-processing apparatus;
An image forming system comprising:   5. The image according to claim 1, wherein an operation unit for operating the image forming system is disposed in at least one of the sheet supply device and the sheet post-processing device. 6. Forming system.   An image reading device that reads image information recorded on a document and sends the image information to the image forming apparatus is disposed on at least one of the sheet supply device and the sheet post-processing device. 6. The image forming system according to any one of 1 to 5. A take-out door for taking out a sheet processed by the sheet post-processing apparatus is provided on a front surface of the sheet post-processing apparatus, and a hinge portion of the take-out door is located on the image forming apparatus side. The image forming system according to claim 1.

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