Image forming apparatus and information processing apparatus

Abstract

To reduce the possibility of erroneously determining that a conveyance failure has occurred.SOLUTION: An image forming apparatus 100 includes: an image forming unit P for forming an image on a recording medium; an operation unit 110 for allowing a user to input information; and a main control unit 101. When image formation on a clear file is instructed and a first size relating to the size of the clear file is input through the operation unit 110, the main control unit 101 sets the length in a conveyance direction of the clear file as a first length. When image formation on a recording medium other than the clear file is instructed and a first size relating to the size of the recording medium other than the clear file is input through the operation unit 110, the main control unit 101 sets the length in a conveyance direction of the recording medium other than the clear file as a second length. The first length is longer than the second length.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus that forms an image on a recording material by an electrophotographic method or an electrostatic recording method. [Background technology]

[0002] Image forming devices generally print images using paper or the like defined in the Japanese Industrial Standards as a recording material. Image forming devices can use various types and sizes of paper, as well as clear files, as recording materials. Patent Document 1 discloses an image forming device that conveys clear files. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-198394 Summary of the Invention [Problem to be solved by the invention]

[0004] Since clear files are used to store standard-sized paper, they are wider and longer than standard-sized paper. When forming an image on such a clear file, there is a risk that the size of the clear file may be the cause of a misfeed.

[0005] In view of the above-mentioned problems, the present invention has as its main object to reduce the possibility of determining that a transport failure has occurred. [Means for solving the problem]

[0006] The image forming apparatus of the present invention comprises a selection means capable of selecting between a first mode in which an image is formed on a first recording material having at least one closed side and a second mode in which an image is formed on a second recording material having no closed side; an input means for inputting information regarding the size of the recording material; an image forming means for forming an image on the recording material; and a control means for, when the first mode is selected by the selection means and the first size is input by the input means as information regarding the size of the first recording material, setting the length in the transport direction of the first recording material to a first length, and, when the second mode is selected by the selection means and the first size is input by the input means as information regarding the size of the second recording material, setting the length in the transport direction of the second recording material to a second length, wherein the first length is longer than the second length. Another aspect of the image forming apparatus of the present invention comprises a selection means capable of selecting between a first mode in which an image is formed on a first recording material having at least one closed side and a second mode in which an image is formed on a second recording material having no closed side; an input means for inputting information regarding the size of the recording material; an image forming means for forming an image on the recording material; and a control means for determining the inter-paper distance during transport based on a reference length obtained by adding the first paper length to an allowable difference between a first paper length in the recording material transport direction set by the input means and an actual second paper length in the recording material transport direction, wherein the allowable difference when the first mode is selected by the selection means is greater than the allowable difference when the second mode is selected by the selection means. The information processing device of the present invention is an information processing device that is communicatively connected to an image forming device having an image forming means that forms an image on a recording material, and is equipped with an input means for inputting information regarding the size of the recording material, a selection means that can select between a first mode in which an image is formed on a first recording material having at least one closed side and a second mode in which an image is formed on a second recording material that does not have a closed side, and a control means that, when the first mode is selected by the selection means and the first size is input by the input means as information regarding the size of the first recording material, sets the length in the transport direction of the first recording material to a first length, and when the second mode is selected by the selection means and the first size is input by the input means as information regarding the size of the second recording material, sets the length in the transport direction of the second recording material to a second length, wherein the first length is longer than the second length. Another aspect of the information processing device of the present invention is an information processing device that is communicatively connected to an image forming device having an image forming means that forms an image on a recording material, and that comprises: an input means for inputting information regarding the size of the recording material; a selection means that can select between a first mode in which an image is formed on a first recording material having at least one closed side and a second mode in which an image is formed on a second recording material that does not have a closed side; and a control means that determines the paper-to-paper distance based on a reference length obtained by adding the first paper length to an allowable difference between a first paper length in the recording material transport direction set by the input means and an actual second paper length in the recording material transport direction, wherein the allowable difference when the first mode is selected by the selection means is a larger value than the allowable difference when the second mode is selected by the selection means. [Effects of the Invention]

[0007] According to the present invention, it is possible to reduce the possibility of erroneously determining that a recording material conveyance failure has occurred. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram illustrating the configuration of an image forming system. [Figure 2] An example diagram comparing the sizes of a clear file and a sheet. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. 1 is a diagram illustrating the configuration of an image forming apparatus. [Figure 6] 10 is a view showing an example of a paper type selection screen. [Figure 7] 10 is a flowchart showing a process up to the start of image forming processing. [Figure 8] FIG. 10 is a diagram illustrating a standard size setting screen. [Figure 9] 10A and 10B are diagrams illustrating examples of guide screens. [Figure 10] FIG. [Figure 11] 10A and 10B are diagrams illustrating examples of a setting screen for document size and double-sided printing. [Figure 12] (a) and (b) are explanatory diagrams of the verification results. [Figure 13] 10 is a flowchart showing a process up to the start of image forming processing. [Figure 14] (a) and (b) are explanatory diagrams of the verification results. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings. In this embodiment, an electrophotographic image forming apparatus will be described as an example, but the present invention is also effective in other image forming apparatuses such as an inkjet type.

[0010] 1 is a configuration diagram of an image forming system including an image forming apparatus according to this embodiment. The image forming system 1X includes an image forming apparatus 100 that forms a toner image on a recording material S, and an operation unit 110 that has a display 111. The image forming system 1X may also include other post-process units such as a relay device or a finisher device.

[0011] The relay device is disposed between the image forming apparatus 100 and various front and rear processing units. The relay device reverses the recording material S conveyed from the image forming apparatus 100 and conveys it to the front and rear processing units, or temporarily stacks it before conveying it to the front and rear processing units. The finisher device performs post-processing such as punching to make holes in the recording material S and stapling to bundle and staple multiple sheets of recording material S, and discharges the bundle of recording materials S after post-processing to a discharge tray. In addition to these post-processing units, the image forming system 1X may also be provided with a recording material supplying device that stores a large amount of recording material S inside and feeds the stored recording materials S to the image forming apparatus 100.

[0012] (Image forming device) The image forming apparatus 100 of this embodiment is a tandem-type full-color printer using an electrophotographic method. Note that the image forming apparatus 100 may also be configured to form images using an electrostatic recording method. The image forming apparatus 100 includes an image forming unit Pa that forms a yellow image, an image forming unit Pb that forms a magenta image, an image forming unit Pc that forms a cyan image, and an image forming unit Pd that forms a black image.

[0013] Image forming apparatus 100 forms a toner image on recording material S based on data related to the toner image contained in image data acquired from external device 1000, such as a document reading device (not shown) or a personal computer communicatively connected to image forming apparatus 100. In addition to sheets made of ordinary paper, such as plain paper, cardboard, rough paper, textured paper, and coated paper, in this embodiment, a clear file made of a plastic sheet material formed into a bag shape can be used as recording material S. Because it is formed into a bag shape, the clear file can store sheets.

[0014] A clear file is made by folding a sheet of plastic material, for example, so that at least one of the overlapping edges (edges) is open and the remaining edges (edges) are closed. In other words, a clear file has at least one closed edge. The open edge (edge) is called the "opening part," and the closed edge (edge) is called the "fixed part." Fixed parts include a folded part formed by folding the plastic material, and a closed part where the edges are fixed using heat or ultrasonic welding, or by bonding with adhesives, etc. Typically, a clear file is closed by fixing two edges, and the remaining two edges are open.

[0015] The conveying process of the recording material S will be described. The recording material S is stored and stacked in a cassette 10, or is stacked on a tray 17. The recording material S is fed from the cassette 10 or the tray 17 by a supply roller 13 in accordance with the timing of image formation. The tray 17 is provided so that it can be opened and closed by the user, for example. The recording material S fed by the supply roller 13 is conveyed to a registration roller 12 arranged midway along a conveying path 114. The registration roller 12 performs skew correction and timing correction on the recording material S before conveying it to a secondary transfer portion T2. ​​The secondary transfer portion T2 is a transfer nip formed by an inner secondary transfer roller 14 and an outer secondary transfer roller 11. The secondary transfer portion T2 transfers a toner image onto the recording material S by applying a secondary transfer voltage to the outer secondary transfer roller 11.

[0016] If the actual length of the recording material S in the conveying direction (hereinafter referred to as "paper length") differs from the set length, it becomes difficult to form an image on the recording material S at the specified position, resulting in a jam of the recording material S. For example, a clear file is larger in size (width and length) than the standard size in order to accommodate standard-sized paper. Generally, a clear file is configured to be larger than standard-sized paper by, for example, 5 to 15 mm in both length and width. Therefore, sheets can be stored without protruding from the clear file. Figure 2 shows a comparison example of the sizes of a clear file and a sheet. The recording material, which is a clear file, is larger in size than standard-sized sheet A (L101 > L103, L102 > L104). Therefore, if the clear file is conveyed with the paper length set to L103, the actual paper length is L101, making the clear file more likely to be detected as a jam than standard-sized paper.

[0017] The allowable difference between the actual sheet length of the recording material S that allows an image to be formed at a predetermined position and the set sheet length is called the jam margin. In this embodiment, a detector 115 for detecting the actual sheet length of the recording material S is provided on the conveying path 114 upstream of the registration rollers 12 in the conveying direction. If the sheet length detected by the detector 115 is longer than the length obtained by adding the jam margin to the set sheet length according to the size of the recording material S (hereinafter referred to as the "jam reference length"), a jam is detected.

[0018] In this embodiment, the jam margin is 5 mm. For example, if the A4 standard size paper length is set to 297 mm, the jam reference length is 302 mm. A clear file for A4 standard size is longer than the A4 standard size paper length, for example, 310 mm, because it needs to store A4 standard size sheets. When such a clear file is transported as A4 standard size recording material S, the paper length detected by detector 115 is longer than the jam reference length. This causes a jam to be detected.

[0019] By lengthening the jam reference length (jam margin), jams will not be detected even if A4-sized clear files are fed as standard A4 size files. However, in this case, the feed interval (paper distance) when feeding the clear files will increase, which may reduce productivity. For this reason, the jam reference length must be set optimally.

[0020] In this embodiment, detector 115 detects the passage of the leading and trailing edges of recording material S in the conveying direction during conveyance. Based on the difference (t) in the passage times of the leading and trailing edges and the conveying speed (v) of recording material S, the distance (d = t × v) from the leading edge to the trailing edge of recording material S is calculated. This distance (d) is detected as the actual paper length of recording material S. Note that the paper length of recording material S may also be detected by other methods.

[0021] This section describes the image forming process in which a toner image is transported to the secondary transfer unit T2 at the same time as the process in which the recording material S is transported to the secondary transfer unit T2. The configuration of the image forming units Pa, Pb, Pc, and Pd will be described. The image forming units Pa, Pb, Pc, and Pd are configured in approximately the same manner except that the colors of the images (toner images) they form are different: yellow, magenta, cyan, and black. Here, we will describe the image forming unit Pd, which forms a black toner image, and will omit descriptions of the other image forming units Pa, Pb, and Pc.

[0022] The image forming unit Pd mainly includes a developing unit 1d, a charging unit 2d, a photosensitive drum 3d, a photosensitive drum cleaner 4d, an exposure unit 5d, and a primary transfer roller 6d. The photosensitive drum 3d is a photosensitive member having a photosensitive layer on its surface and rotates around the drum axis. The charging unit 2d uniformly charges the surface of the rotating photosensitive drum 3d. The exposure unit 5d forms an electrostatic latent image on the charged surface of the photosensitive drum 3d by irradiating it with a laser beam driven based on an image signal. The developing unit 1d develops the electrostatic latent image formed on the photosensitive drum 3d using a developer to form a black toner image on the surface of the photosensitive drum 3d.

[0023] The primary transfer roller 6d is disposed in a position facing the photosensitive drum 3d across the intermediate transfer belt 80. When a primary transfer voltage is applied, the primary transfer roller 6d transfers the toner image formed on the photosensitive drum 3d onto the intermediate transfer belt 80. Residual toner remaining on the photosensitive drum 3d after transfer is collected by the photosensitive drum cleaner 4d.

[0024] Similarly, a yellow toner image is formed on the photosensitive drum 3a of the image forming station Pa, and the toner image is transferred onto the intermediate transfer belt 80 by the primary transfer roller 6a. A magenta toner image is formed on the photosensitive drum 3b of the image forming station Pb, and the toner image is transferred onto the intermediate transfer belt 80 by the primary transfer roller 6b. A cyan toner image is formed on the photosensitive drum 3c of the image forming station Pc, and the toner image is transferred onto the intermediate transfer belt 80 by the primary transfer roller 6c.

[0025] The intermediate transfer belt 80 is an endless belt that is stretched around the inner secondary transfer roller 14 and tension rollers 15 and 16, and is driven in the direction of arrow R2. In this embodiment, the tension roller 16 also serves as a drive roller that drives the intermediate transfer belt 80. The image formation processes of the image forming units Pa to Pd are performed at such a timing that the transferred toner images of each color are sequentially superimposed on the intermediate transfer belt 80. As a result, a full-color toner image is finally formed on the intermediate transfer belt 80.

[0026] The intermediate transfer belt 80 rotates to transport the toner image to the secondary transfer portion T2. ​​The transport of the toner image to the secondary transfer portion T2 is synchronized with the timing at which the recording material S is transported to the secondary transfer portion T2. ​​This allows the toner image to be transferred to a predetermined position on the recording material S. Any residual toner remaining on the intermediate transfer belt 80 after transfer by the secondary transfer portion T2 is removed by a transfer cleaner 22.

[0027] Through the above-described conveying process and image forming process, a toner image is carried on the recording material S. The recording material S is conveyed from the secondary transfer unit T2 to the fixing unit 50. The fixing unit 50 applies heat and pressure to the recording material S bearing the toner image, thereby fixing the toner image to the recording material S. To this end, the fixing unit 50 has a first roller incorporating a heat source and a second roller biased toward the first roller, and the recording material S is nipped and conveyed between the first roller and the second roller. During this process, the recording material S is heated by the heat source and pressurized by the second roller. As a result, the toner image carried by the recording material S is melted and mixed, and fixed to the recording material S as a full-color image.

[0028] The recording material S on which the image has been fixed is guided by a flapper 300 to either a conveying path 301 or a conveying path 305. The flapper 300 guides the recording material S to the conveying path 305 when the printing surface (image forming surface) is not turned over in single-sided printing or when printing on both sides is completed in double-sided printing. The recording material S guided to the conveying path 305 is discharged outside the image forming apparatus 100.

[0029] When printing on the front side (first side) is completed in double-sided printing, or when the printed side is to be reversed in single-sided printing, the flapper 300 guides the recording material S to a conveying path 301. The recording material S is conveyed to a reversing unit 302 via the conveying path 301. The recording material S conveyed to the reversing unit 302 has its conveying direction reversed, and is guided by a flapper 303 to either the conveying path 301 or a double-sided conveying path 304. The conveying direction is reversed in the reversing unit 302, and the recording material S is conveyed to the conveying path 301 or the double-sided conveying path 304, whereby the printed side of the recording material S is reversed.

[0030] When the printing surface is to be reversed in single-sided printing, the flapper 303 guides the recording material S to a conveying path 301. The recording material S guided to the conveying path 301 is discharged from the conveying path 301 to the outside of the image forming apparatus 100 via a conveying path 305. When printing on the front side is completed in double-sided printing, the flapper 303 guides the recording material S to a double-sided conveying path 304. The recording material S guided to the double-sided conveying path 304 is conveyed to a secondary transfer unit T2. As a result, an image is printed on the back side (second side) of the recording material S.

[0031] The developer used in this embodiment is a two-component developer containing toner and a carrier. The toner contains a binder resin, a colorant, and a release agent (wax). Known binder resins can be used. Examples of binder resins that can be used include vinyl copolymers such as styrene-(meth)acrylic copolymers, polyester resins, hybrid resins in which vinyl copolymer units and polyester units are chemically bonded, epoxy resins, and styrene-butadiene copolymers. Known colorants can be used for each of the colors yellow, magenta, cyan, and black.

[0032] Examples of the release agent that can be used include aliphatic hydrocarbon waxes, oxides of aliphatic hydrocarbon waxes, and block copolymers thereof. Examples of aliphatic hydrocarbon waxes include low-molecular-weight polyethylene, low-molecular-weight olefin copolymer waxes, microcrystalline waxes, Fischer-Tropsch waxes, and paraffin waxes. Examples of oxides of aliphatic hydrocarbon waxes include oxidized polyethylene waxes. Block copolymers include waxes whose main component is fatty acid ester, ester waxes, and partially or completely deoxidized fatty acid esters such as deoxidized carnauba wax. Examples of waxes whose main component is fatty acid ester include carnauba wax and Montan acid ester wax. Ester waxes are synthetic reaction products of higher fatty acids, such as behenyl behenate and behenyl stearate, with higher alcohols.

[0033] The operation of such an image forming apparatus 100 is controlled by a main control unit 101. Fig. 3 is an explanatory diagram of the main control unit 101. The main control unit 101 can communicate with a printer unit 120 and an operation unit 110. The printer unit 120 includes each unit used in the image forming process described above.

[0034] The main control unit 101 has a CPU (Central Processing Unit) 102, a ROM (Read Only Memory) 103, a RAM (Random Access Memory) 104, and an image processing unit 105. The CPU 102 controls the overall operation of the image forming system 1X by executing computer programs stored in the ROM 103. The RAM 104 provides a work area for the CPU 102 when executing processing. The image processing unit 105 performs predetermined image processing on image data acquired from the external device 1000, such as converting the image data into a format processable by the exposure devices 5a to 5d of the image forming units Pa to Pd, to generate image signals, which are then transmitted to the image forming units Pa to Pd. The main control unit 101 also detects a jam when the paper length detected by the detector 115 is longer than the jam reference length.

[0035] The printer unit 120 includes a stacking unit 124, a conveying unit 123, a fixing unit 122, and an image forming unit P. The image forming unit P represents the image forming units Pa to Pd described above. The stacking unit 124 is a cassette 10 and a tray 17, and stores or stacks the recording material S. The conveying unit 123 feeds the recording material S from the stacking unit 124, conveys it to the secondary transfer unit T2 and the fixing unit 50, and discharges it outside the image forming system 1X. The conveying unit 123 includes a supply roller 13, a registration roller 12, and flappers 300 and 303. The fixing unit 122 is the fixing unit 50 described above, and fixes the toner image on the recording material S. The image forming unit P forms toner images of each color as described above. The image forming unit P controls the driving of laser light output from the exposure units 5a to 5d based on an image signal acquired from the image processing unit 105.

[0036] In order to perform optimal print settings, the image forming apparatus 100 of this embodiment requires that a paper type be set in response to a user's instruction using the operation unit 110. The operation unit 110 is a user interface having an input interface and a display 111, which is an output interface. The operation unit 110 is used, for example, to obtain the paper type setting for the recording material S used in image formation. FIG. 4 is an explanatory diagram of the configuration of the operation unit 110.

[0037] The operation unit 110 of this embodiment has, as input interfaces, a setting key 1002, a power saving key 1003, a group of hard keys 1104, a reset key 1105, a stop key 1106, and a start key 1107. The operation unit 110 may also have, as an input interface, a touch panel provided on the display 111. The contents input via the input interface (for example, information necessary for creating job information such as the type of recording material S, the number of copies to be printed, and output attribute information) are transmitted to the CPU 102. Using the input interface, the user can input information.

[0038] The setting key 1002 is pressed to perform various settings such as paper type settings. The power-saving key 1003 is pressed to transition the image forming apparatus 100 to or from sleep mode. When the power-saving key 1003 is pressed in normal mode, the image forming apparatus 100 transitions to sleep mode, and when the power-saving key 1003 is pressed in sleep mode, the image forming apparatus 100 transitions to normal mode. The hard key group 1104 includes a numeric keypad, a clear key, and an authentication key. The reset key 1105 is pressed to reset various settings. The stop key 1106 is pressed to stop an ongoing operation. The start key 1107 is pressed to start a printing operation or to instruct the start of other functions. The start key 1107 is equipped with a two-color LED (light emitting diode) of green and red (not shown). The start key 1107 indicates that operation can be started when lit green, and indicates that operation cannot be started when lit red.

[0039] The various keys described above are hardware keys, but may also be realized as software keys displayed on the display 111. Also, the various keys may be realized as a combination of hardware keys and software keys.

[0040] (Examples of other image forming devices) The image forming apparatus 100 illustrated in FIG. 1 prints an image on a recording material S while transporting the recording material S in a horizontal direction parallel to the bottom surface of the image forming apparatus 100. In other words, the transport path 114 along which the recording material S is transported is a horizontal path extending horizontally. Some image forming apparatuses print images on the recording material S while transporting it in a vertical direction (vertical direction) perpendicular to the bottom surface of the image forming apparatus (vertical path). FIG. 5 is a structural diagram of such an image forming apparatus. This image forming apparatus 201 is a tandem-intermediate transfer laser beam printer that utilizes an electrophotographic process. The image forming apparatus 201 forms and outputs a full-color or monochrome image on the recording material S, which is a recording medium, based on image data acquired from an external device 1000 (see FIG. 1) via a network or image data acquired from an image reading device 202 provided above.

[0041] The image forming apparatus 201 has components for forming an image inside a main body 201A, and is provided with an image reading device 202 and an operation unit 502 having a configuration similar to that of the operation unit 110 in Fig. 1 on the upper part of the main body 201A. Between the main body 201A and the image reading device 202 of the image forming apparatus 201, there is provided a discharge space D having a stacking section 223 to which the recording material S after image formation is discharged.

[0042] The image reading device 202 is a scanner that reads an image from a document and generates image data. The image reading device 202 is used, for example, when copying a document. The image reading device 202 of this embodiment is configured as a part of the image forming device 201. However, the image reading device 202 may also be configured as a separate device from the image forming device 201 and electrically connected to the image forming device 201.

[0043] The image forming apparatus 201 includes, in a main body 201A, an image forming mechanism 201B, an intermediate transfer unit 201C, a secondary transfer unit 201D, a fixing unit 201E, and a cassette paper feed unit 230. The main body 201 is also provided with a manual paper feed unit 235.

[0044] The cassette paper feed unit 230 feeds the recording material S from a paper feed cassette 231 that stores the recording material S. The cassette paper feed unit 230 includes a pickup roller 232 and a separation unit that includes a feed roller 233 and a retard roller 234 for separating the recording material S fed from the pickup roller 232. The recording material S is fed one sheet at a time from the paper feed cassette 231 by the pickup roller 232 and the separation unit. In this embodiment, a configuration in which multiple cassette paper feed units 230 (four in this example) are provided is described, but any number of cassette paper feed units 230 may be used. The recording material S fed from the cassette paper feed unit 230 is conveyed to registration rollers 240 via conveyance rollers 280 and 290. A detector 115 similar to that in the image forming apparatus 100 is provided between the conveyance roller 280 and the conveyance roller 290 to detect the actual sheet length of the recording material S.

[0045] In addition to the cassette paper feed unit 230, the recording material S can also be fed from a manual paper feed unit 235. The manual paper feed unit 235 is provided with a tray 236 on which the user manually places the recording material S. Similar to the cassette paper feed unit 230, the manual paper feed unit 235 is provided with a pickup roller and a separation unit, and feeds the recording material S one sheet at a time from the tray 236. The recording material S fed from the manual paper feed unit 235 is also conveyed to the registration rollers 240 via conveyance rollers 280 and 290.

[0046] The image forming mechanism 201B is a four-drum full-color system and includes a laser scanner 210 and four image forming units 211 for forming toner images of four colors: yellow (Y), magenta (M), cyan (C), and black (K). Each image forming unit 211 includes a photosensitive drum 212, a charger 213, and a developing unit 214. A toner cartridge 215 is disposed above the image forming unit 211. The toner cartridge 215 supplies toner to the developing unit 214.

[0047] The intermediate transfer unit 201C includes an intermediate transfer belt 216 wound around a drive roller 216a and a tension roller 216b. Four primary transfer rollers 219 are provided inside the intermediate transfer belt 216 and contact the intermediate transfer belt 216 at positions facing the respective photosensitive drums 212. The intermediate transfer belt 216 is rotated in the direction of the arrow by a drive roller 216a driven by a drive unit (not shown).

[0048] The secondary transfer unit 201D includes a secondary transfer roller 217 disposed opposite the drive roller 216a with the intermediate transfer belt 216 interposed therebetween. The fuser 201E is disposed downstream of the secondary transfer roller 217 in the conveyance direction of the recording material S, and includes a pressure roller 220a and a heating roller 220b. A first discharge roller 225a, a second discharge roller 225b, and a duplex reversing unit 201F are disposed downstream of the fuser 201E in the conveyance direction of the recording material S. The duplex reversing unit 201F includes a reversing roller 222 that can rotate forward and backward, and a re-conveying path R that conveys the recording material S with an image formed on one side thereof to the image forming mechanism 201B.

[0049] The image forming apparatus 201 configured as described above operates as follows. The image forming apparatus 201 receives an instruction to start a print job, as well as image data from the image reading device 202 or the external device 1000, and forms an image on the recording material S according to the image data. Note that a print job refers to a series of operations that execute a conveying process and an image forming process based on a print signal that instructs image formation on the recording material S, from when printing of the image is completed until the recording material S is discharged onto the stacking unit 223. The image forming apparatus 201 receives an instruction to start the print job from the operation unit 502 or the external device 1000.

[0050] The image forming mechanism 201B uniformly charges the surfaces of the photosensitive drums 212 to a potential of a predetermined polarity using the chargers 213. The laser scanner 210 irradiates the uniformly charged surfaces of the photosensitive drums 212 with laser light modulated based on image data. As a result, an electrostatic latent image corresponding to the corresponding color (yellow, magenta, cyan, or black) is formed on the surface of each photosensitive drum 212.

[0051] The image forming mechanism 201B develops the electrostatic latent images formed on the photosensitive drums 212 by the developing devices 214. On each photosensitive drum 212, the electrostatic latent images are developed with toner of the corresponding color, thereby forming a toner image of the corresponding color. The toner images are sequentially transferred by primary transfer rollers 219 from the photosensitive drums 212 onto the rotating intermediate transfer belt 216 in a superimposed state. As a result, a full-color toner image is formed on the intermediate transfer belt 216. The intermediate transfer belt 216 conveys the toner image to the secondary transfer unit 201D by rotating.

[0052] In parallel with this toner image formation operation, recording material S is conveyed one sheet at a time to registration rollers 240 by cassette paper feed unit 230 or manual paper feed unit 235. Registration rollers 240 correct skew of the conveyed recording material S. After skew correction, the recording material S is conveyed by registration rollers 240 to secondary transfer unit 201D in accordance with the timing at which the toner image carried by intermediate transfer belt 216 is conveyed to secondary transfer unit 201D. Secondary transfer unit 201D transfers the full-color toner image from intermediate transfer belt 216 onto recording material S by a secondary transfer bias applied to secondary transfer roller 217.

[0053] The recording material S onto which the toner image has been transferred is transported to a fixing device 201E. The fixing device 201E sandwiches and transports the recording material S in a roller nip formed by a pressure roller 220a and a heating roller 220b. When sandwiching and transporting the recording material S, the fixing device 201E heats the recording material S with the heating roller 220b, thereby melting and mixing the toner of each color on the recording material S. The fixing device 201E also pressurizes the recording material S with the pressure roller 220a, thereby fixing the melted and mixed toner to the recording material S. At this time, the adhesive force of the melted toner causes the recording material S to stick to the heating roller 220b.

[0054] The recording material S with the fixed image is discharged to the discharge space D by either the first discharge roller 225a or the second discharge roller 225b. The recording material S is stacked on a stacking section 223 that protrudes from the bottom surface of the discharge space D. When an image is to be formed on both sides of the recording material S, the recording material S with the image fixed on one side is transported to a re-conveyance path R by the reversing roller 222 and transported again to the image forming mechanism 201B, where an image is formed on the inverted side. The re-conveyance path R is configured to transport the recording material S to a transport path between the transport roller 290 and the registration roller 240.

[0055] In this way, in the image forming apparatus 201, the recording material S is transported along a transport path (vertical path) that extends in the vertical direction. During image formation, the recording material S is transported from the registration roller 240 to the fixing device 201E from the bottom to the top in the vertical direction, with the top side at the leading edge. When transported along the re-conveyance path R, the recording material S is transported from the top to the bottom in the vertical direction, with the bottom side at the leading edge.

[0056] The operation of the image forming apparatus 201 is controlled by a main control unit 101 similar to that shown in Fig. 3. In this case, the stacking unit 124 of the printer unit 120 includes a cassette paper feed unit 230 and a manual paper feed unit 235. The conveying unit 123 includes various rollers such as conveying rollers 280 and 290 and a registration roller 240. The fixing unit 122 includes a fixing device 201E. The image forming unit P includes an image forming unit 211.

[0057] In this embodiment, printing on a clear file is possible by selecting the type of paper (recording material S) to be used for printing from a paper type selection screen. Fig. 6 is a diagram showing an example of the paper type selection screen. A selection screen 1201 is displayed on the display 111. On the selection screen 1201, any recording material S can be selected, and a clear file is provided as an optional paper type.

[0058] When the user selects and presses "clear file" from the pull-down menu on the selection screen 1201, the background of the selected area is displayed in inverse video. Then, when the user presses the confirm button 1203, the fact that the clear file has been selected as the paper type is input to the main control unit 101. The CPU 102 then sets the type of recording material S to clear file.

[0059] ROM 103 stores setting information (image forming conditions) for image formation to prevent degradation of transportability and image quality in accordance with the clear file. CPU 102 acquires the setting information for the clear file from ROM 103 and uses it to control image formation by printer unit 120. This prevents degradation of transportability, such as jams, when printing on a clear file. ROM 103 also stores, as standard sizes, the paper length of standard-size sheets and the paper length of the clear file that contains the sheets. In other words, two paper lengths are associated with one standard size.

[0060] Example 1 An example will be described in which an image is printed using a clear file as recording material S. FIG. 7 is a flowchart showing the process up to the start of the image formation process. In this process, the paper length is changed depending on the type of recording material S, even when the same standard size is set. For example, when an A4 standard size clear file is set as recording material S, the paper length is changed to a paper length longer than that of a normal A4 standard size.

[0061] The main control unit 101 determines whether a clear file is set for the recording material S through the paper type setting (S101). The paper type setting is performed using the selection screen 1201 in FIG. 6 above. When a clear file is set, this is called the first mode, and when a single sheet other than a clear file that does not have a fixed portion or an open portion (does not have a closed side) is set, this is called the second mode.

[0062] If a clear file is set for the recording material S (S101: Y), the main control unit 101 sets a standard size for clear files. FIG. 8 is an example of a standard size setting screen displayed on the display 111. A list of standard sizes for clear files stored in the ROM 103 is displayed on the setting screen 1302. The user selects a standard size for clear files corresponding to the recording material S from the setting screen 1302 using the operation unit 110 and presses the enter button 1303. By pressing the enter button 1303, the main control unit 101 sets the standard size for clear files selected from the operation unit 110 (paper length). The setting content is saved in, for example, the RAM 104. If there is no standard size corresponding to the setting screen 1302, the user can set the paper length of the recording material S using the hard key group 1104 by pressing the set button 1301.

[0063] If a clear file is not set for the recording material S (S101: N), the main control unit 101 sets a standard size for a general sheet (S103). In this case, the standard size setting screen is the same as that shown in FIG. 8. A list of standard sheet sizes stored in the ROM 103 is displayed on the setting screen 1302. The user selects a standard size corresponding to the recording material S from the setting screen 1302 using the operation unit 110 and presses the OK button 1303. By pressing the OK button 1303, the main control unit 101 sets the standard size (paper length) of the sheet selected from the operation unit 110. The setting content is saved in, for example, the RAM 104. If there is no standard size corresponding to the setting screen 1302, the user can set the paper length of the recording material S using the hard key group 1104 by pressing the setting button 1301.

[0064] In this case, even if the paper size is the same, the paper length set by the process of S102 is longer than the paper length set by the process of S103. This is because the paper length of the clear file is set in the process of S102, and the clear file can store paper of the same standard size.

[0065] When the size setting is complete, the main control unit 101 starts the job when the start key 1107 on the operation unit 110 is pressed (S104). The main control unit 101 determines a jam reference length from the set size (paper length) and causes the conveying unit 123 to convey the recording material S at a paper-to-paper distance according to the jam reference length. As a result, even if the recording material S is a clear file, the occurrence of a jam is suppressed and an image is printed.

[0066] When forming an image on a clear file, the clear file is placed on the tray 17 before the job starts. At this time, the main control unit 105 may display a guide screen on the display 111 to guide the clear file in the orientation when placed. FIG. 9 is an example of such a guide screen. The guide screen 1701 in FIGS. 9(a) and 9(b) instructs the user to place the clear file on the tray 17 with the folded portion facing the leading edge in the conveyance direction, and also instructs the side to be printed. Here, the side to be printed is referred to as the obverse side. 9A is a message urging the user to place the clear file with the folded portion of the clear file facing up in the conveying direction. The image forming apparatus 100 prints an image on the recording material S while conveying it in a horizontal lateral path. In this case, by placing the clear file on the tray 17 with the print surface facing up, the image is printed on the surface of the clear file. 9(b) is a message urging the user to place the clear file with the folded portion of the clear file facing up in the conveying direction. The image forming apparatus 201 prints an image on the recording material S while conveying it in a vertical path. In this case, by placing the clear file on the tray 236 with the front side, which is the printing side, facing down, the image is printed on the front side of the clear file.

[0067] When double-sided printing is performed, the main control unit 101 may display on the display 111 a guide screen, as in single-sided printing, that guides the orientation of the recording material S when it is placed, as shown in FIG. 9. When double-sided printing is performed, once an image is formed on the first side of the clear file, it is temporarily ejected outside the machine. Thereafter, the printed side (image-formed side) is inverted to the second side, and the clear file is placed again on the tray 17. Although this is the same guide screen as when single-sided printing is performed, its meaning is different.

[0068] The guide screen 1701 in FIG. 9(a) is a message urging the user to place the clear file with the front side (first side) facing up, with the folded part of the clear file at the leading edge in the conveyance direction and the closed part at the rear side. The guide screen 1701 in FIG. 9(a) is displayed when an image is to be formed on the first side. The guide screen 1701 in FIG. 9(b) is a message urging the user to place the clear file with the back side (second side) facing up, with the folded part of the clear file at the leading edge in the conveyance direction and the closed part at the front side. The guide screen 1701 in FIG. 9(b) is displayed when an image is to be formed on the second side after printing on the first side is completed. The front side and the rear side are directions perpendicular to the conveyance direction, and the front side of the image forming apparatus 100 is the front side, and the rear side of the image forming apparatus 100 is the rear side.

[0069] This instruction is a message when placing a clear file on tray 17 of image forming apparatus 100, and when placing a clear file on tray 236 of image forming apparatus 201, the front and back sides are instructed to be reversed. That is, when using image forming apparatus 201, guide screen 1701 in Fig. 9(b) is displayed when forming an image on the first side, and guide screen 1701 in Fig. 9(a) is displayed when forming an image on the second side.

[0070] In this way, the guide screen 1701 is a message to prompt the user to place the clear file on the tray 17, 236 so that the fixed part of the clear file is at the leading edge in the transport direction. If the clear file is transported with the open part at the leading edge, a jam may occur. By transporting the clear file with the fixed part at the leading edge, the possibility of a jam occurring can be reduced.

[0071] Furthermore, when performing double-sided printing, the main control unit 101 may display an instruction screen shown in Fig. 10 on the display 111. This instruction screen is displayed on the display 111 at the start of a job or when image formation on the first side is completed and the clear file is ejected. When the main control unit 101 detects that printing on the front side (first side) is completed and the clear file has been placed on the tray 17, it erases the instruction screen of Fig. 10 from the display 111 and starts printing on the back side (second side).

[0072] In the present embodiment, various printing-related settings are configured by the user operating the operation unit 110. However, similar processing is possible when the user operates the external device 1000. The external device 1000 is an information processing device equipped with an input device and a display. The external device 1000 has the functions of the main control unit 101 and, for example, a printer driver for using the image forming system 1X is installed in the external device 1000. The printer driver displays screens for selecting items to be set in the screens of FIGS. 6 and 8 on the display of the external device 1000 as processing progresses. The display of the external device 1000 may also display a guide screen of FIG. 9 or an instruction screen of FIG. 10 as processing progresses. FIG. 11 is an exemplary diagram of a setting screen for document size and double-sided printing displayed on the display 1502 of the external device 1000. Even when the settings are configured by the external device 1000, printing on a clear file is possible.

[0073] We verified the effectiveness of storing paper lengths corresponding to standard sizes for clear files in the ROM 103 in addition to the paper lengths of standard-sized sheets. Here, we used clear files as the recording material S and verified whether or not paper could be passed through by changing the standard size settings. Figure 12 is an explanatory diagram of the verification results.

[0074] Fig. 12(a) shows the paper length when the recording material S is transported with its long side in the transport direction. As the paper lengths for each size from A3 to B5, the paper length of a sheet (standard paper length) and the paper length of a clear file (clear file length) are stored in ROM 103. Fig. 12(b) shows the paper length when the recording material S is transported with its short side in the transport direction. As the paper lengths for each size from A3 to B5, the paper length of a sheet (standard paper length) and the paper length of a clear file (clear file length) are stored in ROM 103.

[0075] When the recording material S is a clear file and the paper length is set to the standard paper length, a jam is detected, but when the paper length is set to the clear file length, no jam is detected. This result shows that regardless of whether the conveyance direction is the long side or short side of the recording material S, if the paper length for a clear file is set, a jam will not be detected. In other words, when a clear file is selected as the recording material S on the selection screen 1201 in FIG. 6 and the paper size is set on the setting screen 1302 in FIG. 8, if the paper size is set to be larger than the standard sheet size, jam detection will be suppressed.

[0076] Example 2 A case where an image is printed using a clear file as the recording material S will be described. In the first embodiment, standard sizes (paper lengths) are prepared separately for sheets and clear files. In the second embodiment, the occurrence of jams is suppressed by adjusting the jam margin according to the type of recording material S. FIG. 13 is a flowchart showing the process up to the start of image formation processing in the second embodiment.

[0077] The main control unit 101 displays the paper type selection screen of FIG. 6 on the display 111, and allows the user to select the paper type (S201). The main control unit 101 acquires information indicating the paper type selection result from the operation unit 110. The main control unit 101 displays the standard size setting screen of FIG. 8 on the display 111, and allows the user to select the standard size (S202). The main control unit 101 acquires information indicating the standard size selection result from the operation unit 110. The standard size in this case is the standard size for sheets, not the standard size for clear files. This sets the paper length of the recording material S.

[0078] The main control unit 101 determines whether the paper type selected in S201 is a clear file (S203). The first mode is when a clear file is selected, and the second mode is when a single sheet of paper that does not have a fixed portion or an open portion (no closed side) other than a clear file is selected. If the paper type is a clear file (S203: Y), the main control unit 101 changes the jam margin to a value corresponding to a clear file (S204). Specifically, the jam margin is changed to a value larger than that for a sheet. The main control unit 101 starts the job when the start key 1107 on the operation unit 110 is pressed (S205). If the paper type is not a clear file (S203: N), the main control unit 101 does not change the jam margin, and starts the job when the start key 1107 on the operation unit 110 is pressed (S205). The jam margin is changed depending on the size of the recording material S. For example, the larger the size of the recording material S, the larger the jam margin is set.

[0079] As in the first embodiment, when forming an image on a clear file, before the job starts, a guide screen as shown in Fig. 9 may be displayed on the display 111. In addition, in the case of double-sided printing, an instruction screen as shown in Fig. 10 may be displayed on the display 111.

[0080] The main control unit 101 determines the jam reference length from the set jam margin, and causes the conveying unit 123 to convey the recording material S at a paper-to-paper distance according to the jam reference length. If the paper type of the recording material S is a clear file, the jam margin is set to a value corresponding to the clear file, so the jam reference length is longer than in the case of a sheet. As a result, even if the recording material S is a clear file, jam detection is suppressed and an image is printed.

[0081] As in the first embodiment, in the second embodiment, the user can operate the external device 1000 to make various settings related to printing. On the display of the external device 1000, a screen for setting the items set on the screens of Fig. 6 and Fig. 8 is displayed by the printer driver as the processing progresses. Also, on the display of the external device 1000, a guide screen of Fig. 9 or an instruction screen of Fig. 10 may be displayed as the processing progresses. Even when the settings are made by the external device 1000, printing onto a clear file is possible.

[0082] The effectiveness of the process of changing the jam margin as described above was verified. Here, a standard A4 size clear file was used as the recording material S, and it was verified whether or not the paper could be passed with different jam margins. Figure 14 is an explanatory diagram of the verification results.

[0083] FIG. 14(a) shows the relationship between the increase in the jam margin and whether or not a jam occurred. By increasing the jam margin, jams are suppressed and paper can be passed through. FIG. 14(b) shows the increase in the jam margin where no jam occurred when standard-sized clear files of A3 to B5 sizes are passed through. Note that the increase in the jam margin is an example, and paper can be passed through for each size as long as the increase is between 5 mm and 25 mm. In other words, these results show that the jam margin needs to be set according to the size of the clear file.

Claims

1. a selection means for selecting between a first mode for forming an image on a first recording material having at least one closed side and a second mode for forming an image on a second recording material having no closed side; an input means for inputting information regarding the size of the recording material; an image forming means for forming an image on a recording material; a control unit that sets a length of the first recording material in the conveying direction to a first length when the first mode is selected by the selection unit and a first size is input by the input unit as information about the size of the first recording material, and that sets a length of the second recording material in the conveying direction to a second length when the second mode is selected by the selection unit and the first size is input by the input unit as information about the size of the second recording material, The first length is longer than the second length. Image forming device.

2. the control means sets a first inter-sheet distance when the first recording material is conveyed when the first mode is selected by the selection means to be larger than a second inter-sheet distance when the second recording material is conveyed when the second mode is selected by the selection means.

2. The image forming apparatus according to claim 1.

3. the control means determines the inter-sheet distance based on a reference length obtained by adding the first sheet length to an allowable difference between a first sheet length in the recording material transport direction set by the input means and an actual second sheet length in the recording material transport direction.

3. The image forming apparatus according to claim 2.

4. a tolerance when the first mode is selected by the selection means is greater than a tolerance when the second mode is selected by the selection means; 4. The image forming apparatus according to claim 3.

5. When the first mode is selected by the selection means, the control means causes the display means to display a setting screen for setting a standard size of the recording material, and sets the first length based on the standard size set from the setting screen by the input means, and when the second mode is selected by the selection means, causes the display means to display the setting screen, and sets the second length based on the standard size set from the setting screen by the input means.

2. The image forming apparatus according to claim 1.

6. The recording medium further includes a storage unit for storing the first length corresponding to the standard size of the first recording material and the second length corresponding to the standard size of the second recording material, When the first mode is selected by the selection means, the control means acquires the first length of the first recording material from the storage means based on the standard size set from the setting screen by the input means, and when the second mode is selected by the selection means, acquires the second length of the second recording material from the storage means based on the standard size set from the setting screen by the input means.

6. The image forming apparatus according to claim 5.

7. a selection means for selecting between a first mode for forming an image on a first recording material having at least one closed side and a second mode for forming an image on a second recording material having no closed side; an input means for inputting information regarding the size of the recording material; an image forming means for forming an image on a recording material; a control means for determining a distance between sheets during conveyance based on a reference length obtained by adding the first sheet length to an allowable difference between a first sheet length in the conveyance direction of the recording material set by the input means and an actual second sheet length in the conveyance direction of the recording material, a tolerance when the first mode is selected by the selection means is greater than a tolerance when the second mode is selected by the selection means; Image forming device.

8. The control means changes the allowable amount in accordance with the size of the recording material.

8. The image forming apparatus according to claim 7.

9. When the first mode or the second mode is selected by the selection means, the control means causes the display means to display a setting screen for setting a standard size of the recording material, and acquires the first paper length based on the standard size set on the setting screen by the input means.

8. The image forming apparatus according to claim 7.

10. The control unit detects a jam when the second paper length is longer than the reference length.

8. The image forming apparatus according to claim 7.

11. a detection means for detecting the length of the recording material in the conveying direction is provided in the conveying path of the recording material; The control unit obtains the second paper length from the detection unit.

8. The image forming apparatus according to claim 7.

12. The first recording material is a clear file made of plastic and formed into a bag shape.

8. The image forming apparatus according to claim 1.

13. An information processing apparatus communicably connected to an image forming apparatus including an image forming unit that forms an image on a recording material, an input means for inputting information regarding the size of the recording material; a selection means for selecting between a first mode for forming an image on a first recording material having at least one closed side and a second mode for forming an image on a second recording material having no closed side; a control unit that sets a length of the first recording material in the conveying direction to a first length when the first mode is selected by the selection unit and a first size is input by the input unit as information about the size of the first recording material, and that sets a length of the second recording material in the conveying direction to a second length when the second mode is selected by the selection unit and the first size is input by the input unit as information about the size of the second recording material, The first length is longer than the second length. Information processing device.

14. An information processing apparatus communicably connected to an image forming apparatus including an image forming unit that forms an image on a recording material, an input means for inputting information regarding the size of the recording material; a selection means for selecting between a first mode for forming an image on a first recording material having at least one closed side and a second mode for forming an image on a second recording material having no closed side; a control unit that determines the distance between sheets based on a reference length obtained by adding the first sheet length to an allowable difference between a first sheet length in the recording material transport direction set by the input unit and an actual second sheet length in the recording material transport direction, the tolerance when the first mode is selected by the selection means is greater than the tolerance when the second mode is selected by the selection means, Information processing device.

Images