Recording material conveying device and image forming system

Abstract

To provide a recording material conveyance device which can suppress lowering of reliability at the time of image formation.SOLUTION: A recording material conveyance device includes a first conveyance part for conveying a recording material supplied from a recording material supply part, a second conveyance part which is branched from the first conveyance part and conveys a recording material without through an image formation part, a third conveyance part which is branched from the first conveyance part and conveys the recording material through the image formation part, and a detection part for detecting recording material characteristics of the recording material. The recording material whose recording material characteristics have been detected by the detection part can be discharged from the second conveyance part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a recording material transport device and an image forming system having the recording material transport device. [Background technology]

[0002] In an image forming apparatus, multiple types of recording materials may be used. In this case, the quality of the formed image can be improved by appropriately setting the image forming conditions such as the transfer voltage and fixing temperature of the toner during image formation according to the type and physical properties of the recording material. In addition, by conveying the recording material under more appropriate conveying conditions according to the type and physical properties of the recording material, it is possible to suppress the occurrence of recording material conveying failure such as jams, image misalignment, recording material deviation, etc.

[0003] As an image forming apparatus that optimizes image formation conditions according to the type and physical properties of such recording materials, for example, a configuration has been proposed in which a detection unit for detecting the type and physical properties of the recording material (hereinafter referred to as recording material characteristics) is arranged in the recording material transport path (for example, Patent Document 1).Furthermore, a configuration has been proposed in which, if the recording material characteristics detected by the detection unit differ from the settings, the recording material is discharged from the image forming apparatus without forming an image on it (for example, see Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-128269 A [Patent Document 2] JP 2020-8621 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-mentioned image forming apparatus, the recording material whose recording material characteristics have been detected is discharged after passing through the image forming section. However, if a recording material having characteristics (electrification, creases, thickness, stiffness, moisture content, etc.) that are not suitable for image formation is passed through the image forming section, there is a possibility that the reliability of image formation will decrease. For example, if a recording material that has been deformed due to creases or the like is transported, transport problems such as paper jams (so-called jams) are likely to occur, and transport reliability during image formation will decrease. In addition, for example, when the detection section measures electrical resistance as a recording material characteristic, the recording material may be charged. For example, when the recording material is paper, which is an insulator, the surface electrical resistance is 10 10 ~10 12 In this case, the residual potential of the recording material is not discharged in a short time, and the recording material sticks to the image forming unit, and the transfer of the charge, which is important in the electrophotographic process, is not performed correctly. This may cause a decrease in the reliability of the image forming operation in the image forming unit.

[0006] In order to solve the above-mentioned problems, the present invention provides a recording material conveying device and an image forming system capable of suppressing a decrease in reliability during image formation. [Means for solving the problem]

[0007] The recording material conveying device of the present invention comprises: a conveying path for conveying the recording material supplied from the recording material supplying section to an image forming section; a branching path branching off from the conveying path; and a detection section disposed on the conveying path upstream of the branching point of the branching path and detecting a value corresponding to a recording material characteristic of the recording material. Equipped with.

[0008] The image forming system of the present invention includes an image forming unit for forming an image on a recording material, a conveying path for conveying the recording material supplied from the recording material supplying section to an image forming section; a branching path branching off from the conveying path; and a detection section disposed on the conveying path upstream of the branching point of the branching path and detecting a value corresponding to a recording material characteristic of the recording material. Equipped with. Effect of the Invention

[0009] According to the present invention, it is possible to provide a recording material conveying device and an image forming system capable of suppressing a decrease in reliability during image formation. [Brief description of the drawings]

[0010] [Figure 1]1 is a diagram showing a schematic configuration of an image forming system according to a first embodiment. [Diagram 2] 1 is a system block diagram of an image forming system according to a first embodiment. [Diagram 3] 2 is a functional block diagram of a control unit of the image forming system according to the first embodiment. FIG. [Figure 4] 6 is a flowchart of a detection process of recording material characteristics in the image forming system according to the first embodiment. [Diagram 5] FIG. 13 is a diagram showing a schematic configuration of an image forming system according to a second embodiment. [Figure 6] 10 is a flowchart of a detection process of recording material characteristics in an image forming system according to a second embodiment. [Figure 7] FIG. 13 is a diagram showing a schematic configuration of an image forming system according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, examples of embodiments of the present invention will be described, but the present invention is not limited to the following examples. The explanation will be given in the following order. 1. First embodiment of recording material conveying device and image forming system 2. Second embodiment of recording material conveying device and image forming system 3. Third embodiment of recording material conveying device and image forming system

[0012] 1. Recording Material Conveying Device and Image Forming System FIG. 1 shows a schematic configuration diagram of an image forming system including a recording material conveying device according to the present embodiment. The image forming system 10 shown in FIG. 1 includes a recording material supplying device 100, a recording material conveying device 400, an image forming device 200, and a post-processing device 300. In the image forming system 10, a recording material S loaded in a recording material supplying device 100 is supplied to an image forming device 200 via a recording material conveying device 400. Then, after an image is formed on the recording material S by the image forming device 200, the recording material S is conveyed from the image forming device 200 to a post-processing device 300. Then, after a predetermined post-processing is performed on the recording material S after the image forming process in the post-processing device 300, the recording material S is discharged from the post-processing device 300.

[0013] [Recording material supply device] In the image forming system 10, the recording material supplying device 100 stores recording materials for image formation, and supplies a recording material S to the image forming apparatus 200 in accordance with an image formation job. As shown in Fig. 1, the recording material supplying device 100 includes a conveying section 50, and a recording material supplying section 70 as a recording material storage section.

[0014] The recording material supplying section 70 is composed of, for example, a plurality of paper feed trays arranged inside the recording material supplying device 100. The recording material supplying section 70 is capable of loading a plurality of sheets of recording material S in a stacked state. Fig. 1 illustrates a configuration including four recording material supplying sections 70 arranged vertically. Each recording material supplying section 70 individually stores recording materials of different types and sizes.

[0015] The transport section 50 includes a take-out roller (not shown) that takes out the recording material from each recording material supply section 70, and a plurality of transport rollers 54 that are provided along a predetermined recording material transport path for transporting the recording material. Therefore, the transport path of the transport section 50 merges the plurality of recording material supply sections 70 into one path and is connected to the recording material transport device 400. As a result, the transport section 50 drives the transport rollers 54 to transport the recording material S fed from the recording material supply section 70 to the recording material transport device 400.

[0016] [Recording material transport device] The recording material conveying device 400 includes an entrance 55 through which the recording material S is conveyed into the recording material conveying device 400, a first conveying section 51, a second conveying section 52, and a third conveying section 53 which convey the recording material S, a first discharge section 56 and an exit 57 which convey the recording material S, and a first detection section 71 and a second detection section 72 as detection sections which detect the characteristics of the recording material S.

[0017] (Transportation section) The recording material conveying device 400 includes a first conveying section 51, a second conveying section 52, and a third conveying section 53. The first conveying section 51, the second conveying section 52, and the third conveying section 53 include a plurality of conveying rollers 54 and the like for conveying the recording material S along a conveying path constituting each conveying section.

[0018] The first conveying section 51 constitutes a conveying path between an entrance 55 through which the recording material S is conveyed from the recording material supplying device 100 to the recording material conveying device 400, and a branching section 58 at which the second conveying section and the third conveying section branch off from the first conveying section 51. That is, the conveying path of the recording material S branches off into the second conveying section and the third conveying section on the downstream side of the first conveying section 51 and the branching section 58 in the recording material conveying direction. With this configuration, the recording material conveyed by the first conveying section 51 is conveyed to either the second conveying section or the third conveying section on the downstream side of the branching section 58.

[0019] The second conveying section 52 constitutes a conveying path from a branching section 58 to a first discharge section 56 provided at the top of the recording material conveying device 400, downstream of the first conveying section 51 in the recording material conveying direction. The recording material S conveyed from the first conveying section 51 to the second conveying section 52 through the branching section 58 is discharged from the first discharge section 56 to the outside of the recording material conveying device 400 and the image forming system 10. For this reason, the second conveying section 52 is provided in the recording material conveying device 400 in order to convey the recording material S without passing through the image forming section 240 of the image forming apparatus 200.

[0020] The third conveying section 53 constitutes a conveying path from the branching section 58 to the discharge outlet 57 on the downstream side of the first conveying section 51 in the recording material conveying direction. The recording material S conveyed from the first conveying section 51 to the second conveying section 52 through the branching section 58 passes through the discharge outlet 57 and is conveyed from the recording material conveying device 400 to the image forming apparatus 200. For this reason, the third conveying section 53 is provided in the recording material conveying device 400 in order to convey the recording material S via the image forming section 240 of the image forming apparatus 200. In addition, the image forming system 10 is configured so that the recording material S transported by the third conveying section 53 is discharged from the second discharge section 351 arranged in the post-processing device 300, but when the recording material transporting device 400 is used alone, the discharge outlet 57 is used as the discharge section (second discharge section) for the recording material S transported by the third conveying section 53.

[0021] The first conveying section 51 is provided with a second detection section 72 that detects the characteristics of the recording material S. Also, the second conveying section 52 is provided with a first detection section 71 that detects the characteristics of the recording material S. The recording material S conveyed to the first conveying section 51 has its recording material characteristics detected by a second detection section 72 arranged in the path. Furthermore, the recording material S conveyed from the first conveying section 51 to the second conveying section 52 through the branching section 58 has its recording material characteristics detected by a first detection section 71 arranged in the path. The first detection section 71 is arranged along the conveying path of the second conveying section 52 between the branching section 58 and the first discharge section 56. The second detection section 72 is arranged along the conveying path of the first conveying section 51 between the entrance 55 and the branching section 58.

[0022] That is, in the first conveying section 51, the second detection section 72 is disposed upstream of the branching section 58 in the recording material conveying direction, and in the second conveying section 52, the first detection section 71 is disposed downstream of the branching section 58 in the recording material conveying direction. Only the recording material S conveyed from the first conveying section 51 to the second conveying section 52 is conveyed to the first detection section 71. On the other hand, all the recording material S conveyed through the first conveying section 51 is conveyed to the second detection section 72, so that the recording material S conveyed from the first conveying section 51 to the second conveying section 52 and passing through the branching section 58 and conveyed from the first conveying section 51 to the third conveying section 53 is also conveyed to the second detection section 72.

[0023] For this reason, the first detection section 71 detects the recording material characteristics of only a portion of the recording materials S that are transported to the recording material transport device 400, and that pass through the branching section 58 and are transported by the second transport section 52. The second detection section 72 can detect the recording material characteristics of all the recording materials S transported to the recording material transport device 400, regardless of whether the transport path after passing through the branching section 58 is the second transport section 52 or the third transport section 53. In FIG. 1, an example in which two media sensors are arranged as the first detection unit 71 and the second detection unit 72 is shown.

[0024] The second transport section 52 is preferably configured such that the transport distance of the recording material S downstream of the branching section 58 is equal to or greater than the length of the long side of the recording material S that can be accommodated in the recording material supplying device 100 and transported by the recording material transporting device 400. For example, the second transport section 52 is preferably configured to have a length equal to or greater than the long side of the maximum standard size, excluding long paper such as roll paper. The transport distance of the recording material S upstream of the branching portion 58 of the first transport section 51 is not particularly limited as long as the required number of second detection sections 72 can be arranged and the recording material S can be transported stably.

[0025] It is preferable that the third conveying section 53 is configured such that the conveying distance of the recording material S from the branching section 58 to the discharge outlet 57 is shorter than the length of the second conveying section 52. It is preferable that the third conveying section 53 is configured such that the conveying distance of the recording material S from the branching section 58 to the discharge outlet 57 is the shortest.

[0026] (Detection unit) The first detection unit 71 detects the recording material characteristics of the recording material S transported to the second transport unit 52 under the control of the control unit 90 (FIG. 2). The second detection unit 72 detects the recording material characteristics of the recording material S transported to the first transport unit 51 under the control of the control unit 90 (FIG. 2). The first detection unit 71 and the second detection unit 72 are each constituted by, for example, a known media sensor.

[0027] The first detection section 71 disposed in the second conveying section 52 preferably detects the recording material characteristics in a state where the conveyance of the recording material S is stopped or in a state where the conveyance of the recording material S is slower than the normal conveying speed for image formation. By detecting the recording material characteristics in a stopped state or a low-speed conveying state of the recording material S, it is possible to improve the detection accuracy of the recording material characteristics. For this reason, it is preferable that the first detection section 71 is provided with a sensor that detects the recording material characteristics in a state where the conveyance of the recording material S is stopped or the conveying speed is slowed, which makes it possible to improve the detection accuracy of the recording material characteristics.

[0028] Moreover, it is preferable that the second detection section 72 disposed in the first transport section 51 detects the recording material characteristics while the recording material S is being transported at the normal transport speed during image formation. By detecting the recording material characteristics at the normal transport speed, it is possible to detect the recording material characteristics without reducing the productivity of the image formation job. For this reason, it is preferable that the second detection section 72 is provided with a sensor that detects the recording material characteristics of the recording material S in the transported state.

[0029] The first detection unit 71 and the second detection unit 72 detect the type (e.g., plain paper, high-quality paper, glossy paper, etc.) and size of the recording material S, and the physical properties of the recording material S. Examples of the physical properties of the recording material S that are detected include the thickness, basis weight, surface condition such as smoothness, stiffness, charge amount, moisture content, and grain (angle of the fiber direction of the recording material).

[0030] Furthermore, the first detection unit 71 and the second detection unit 72 are equipped with various sensors for detecting recording material characteristics. For example, the first detection unit 71 and the second detection unit 72 are equipped with an imaging type sensor for detecting the type of recording material S. The imaging type sensor is equipped with a light source that irradiates light onto the front surface of the recording material S, a light source that irradiates light from the back surface of the recording material S, and an imaging element that images the front surface of the recording material S. An image of the reflective state when the front surface of the recording material S is irradiated and an image of the transmissive state when the back surface of the recording material S is irradiated are obtained.

[0031] The first detection unit 71 also includes an optical sensor and a weight sensor for detecting the size, weight, and basis weight of the recording material S. The optical sensor has a light receiving element that detects the edge of the recording material S on an inspection table through which the conveyed recording material S passes. The weight sensor detects the weight per unit area of ​​the recording material S from the change in weight of the inspection table when the recording material S passes. The size and area of ​​the recording material S are detected from the output of the optical sensor, and the basis weight can be obtained from the weight per unit area of ​​the recording material S detected by the weight sensor.

[0032] For example, the first detection unit 71 has a sensor that detects the electrical characteristics of the recording material S as the recording material characteristics. The first detection unit 71 detects the electrical resistance value, charge amount, moisture content, etc. of the recording material S as the recording material characteristics of the recording material S by charging the recording material S with the sensor. Further, for example, the first detection unit 71 has a sensor that detects the recording material characteristics by a test that directly contacts the recording material S. The first detection unit 71 detects the stiffness of the recording material S as the recording material characteristic by the sensor that directly contacts the recording material S.

[0033] The second detection section 72 preferably includes a sensor that detects the recording material characteristics without contacting the recording material S. The second detection section 72 detects the recording material characteristics without deforming the recording material due to an external force, thereby making it possible to suppress the occurrence of transport problems, paper jams (so-called jams), and the like when the recording material S is transported in the image forming apparatus 200, particularly when the recording material S is transported in the image forming section 240 or the fixing section 248. Moreover, the second detection unit 72 preferably includes a sensor that detects the recording material characteristics without charging the recording material S. By detecting the recording material characteristics without charging the recording material S, the second detection unit 72 can accurately detect transport problems (jams) caused by the recording material S sticking during transport, and transfer of charges that are important in the electrophotographic process in the image forming unit 240, such as the transfer of a toner image from the intermediate transfer belt 246 to the recording material S. Since the second detection unit 72 detects the recording material characteristics in a non-contact and non-charged manner, the image forming system 10 can suppress a decrease in the reliability of image formation by reducing problems with the transport of the recording material S and improving the transfer accuracy in image formation.

[0034] [Image forming device] The image forming apparatus 200 shown in FIG. 1 includes an operation display unit 220, a scanner 230, an image forming unit 240, a conveying unit 250, and the like.

[0035] The operation display unit 220 is composed of an operation section and a display section. The display unit is configured with a display device such as an LCD (Liquid Crystal Display), and displays various screens according to instructions of a display signal input from the control unit 90 (FIG. 2). The operation unit includes a touch panel formed to cover the display screen of the display unit, and various operation buttons such as numeric buttons and a start button, and outputs an operation signal based on a user's operation to a control unit 90 described later. The operation unit accepts operation instructions from the user.

[0036] Scanner 230 optically scans an original document transported from an ADF (Auto Document Feeder) onto a contact glass or an original document placed on the contact glass, forms an image of the reflected light of light scanned from a light source onto the original document on the light receiving surface of a CCD (Charge Coupled Device) sensor, reads the original document image, A / D converts the read image, and generates image data.

[0037] The image forming unit 240 forms an image on the recording material S based on image data. The image forming unit 240 includes photoconductor drums 241Y, 241M, 241C, and 241K corresponding to the respective colors of yellow (Y), magenta (M), cyan (C), and black (K), charging units 242Y, 242M, 242C, and 242K, exposure units 243Y, 243M, 243C, and 243K, developing units 244Y, 244M, 244C, and 244K, and primary transfer rollers 245Y, 245M, 245C, and 245K. The image forming unit 240 also includes an intermediate transfer belt 246, a secondary transfer roller 247, and a fixing unit 248.

[0038] The charging sections 242Y, 242M, 242C, and 242K uniformly charge the photoconductor drums 241Y, 241M, 241C, and 241K. The exposure units 243Y, 243M, 243C, and 243K are composed of a laser light source, a polygon mirror, a lens, and the like, and scan and expose the surfaces of the photoconductor drums 241Y, 241M, 241C, and 241K with a laser beam based on image data of each color to form an electrostatic latent image. The developing units 244Y, 244M, 244C, and 244K develop the electrostatic latent images on the photoconductor drums 241Y, 241M, 241C, and 241K by attaching toner of each color to the electrostatic latent images.

[0039] The primary transfer rollers 245Y, 245M, 245C, and 245K sequentially transfer (primary transfer) the toner images of each color formed on the photoconductor drums 241Y, 241M, 241C, and 241K onto the intermediate transfer belt 246. That is, a color toner image is formed on the intermediate transfer belt 246 in which the toner images of four colors are superimposed. The secondary transfer roller 247 transfers the color toner image on the intermediate transfer belt 246 all at once onto one side of the recording material S supplied from the supply tray (secondary transfer). The fixing unit 248 fixes the toner image onto the recording material S by applying heat and pressure to the recording material S by passing the recording material S through a nip portion formed by a fixing roller and a pressure roller.

[0040] The conveying section 250 includes a plurality of conveying rollers 54 and the like that are provided along a predetermined conveying path for conveying the recording material S. The conveying section 250 conveys the recording material along the predetermined conveying path in the image forming apparatus 200 by driving the conveying rollers 54. Then, the recording material S after image formation is conveyed to the post-processing apparatus 300.

[0041] [Post-processing device] The post-processing device 300 receives the recording material S on which an image has been formed by the image forming device 200. The post-processing device 300 includes, for example, a plurality of post-processing units, and a predetermined post-processing is performed in a post-processing unit designated by a job. For example, the post-processing device 300 includes post-processing units that perform processes such as perforation, folding, foil stamping, binding, cutting, stapling, gluing, and binding. In the post-processing device 300, the recording material S on which the image forming process has been performed and which has been transported from the image forming device 200 is transported by a transport section 350 to a post-processing unit (not shown), where a predetermined post-processing is performed on the recording material S. The recording material S transported by the transport section 350 is discharged from a second discharge section 351 provided along the transport path, and is discharged onto a paper discharge tray 352.

[0042] [System block diagram] Fig. 2 shows a system block diagram of each device constituting the image forming system 10 shown in Fig. 1 described above. As shown in Fig. 2, the image forming system 10 includes a control unit 90, a storage unit 98, a communication unit 99, a scanner 230, an image processing unit 80, a recording material supply unit 70, an image forming unit 240, a first detection unit 71, a second detection unit 72, and conveying units 51, 52, 53, 250, and 350. Note that, in the following, a description of the configuration that overlaps with the description of the image forming system 10 shown in Fig. 1 described above will be omitted.

[0043] The control unit 90 is composed of, for example, a CPU (Central Processing Unit) 91, a ROM (Read Only Memory) 92, and a RAM (Random Access Memory) 93. The CPU 91 reads out various processing programs stored in the ROM 92, loads them in the RAM 93, and centrally controls the operations of each part of the image forming system 10 according to the loaded programs. The ROM 92 stores various processing programs for controlling each unit of the image forming system 10, parameters and table data required for executing the programs, various files, and the like. The RAM 93 is made up of a volatile semiconductor memory, and forms a work area for temporarily storing various processing programs read from the ROM 92, input or output data, parameters, etc., during various processes executed and controlled by the CPU 91.

[0044] The storage unit 98 stores, for example, image data received from an external device. The storage unit 98 also stores various processing programs executed by the CPU 91, information on the processing functions of the device itself required to execute the programs, image data read by the scanner 230, image data input from a client device (not shown) and the like, recording material characteristics of the recording material S detected by the first detection unit 71 and the second detection unit 72, and the like. The storage unit 98 may be configured, for example, by a non-volatile memory such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or a flash memory.

[0045] The communication unit 99 is composed of a NIC (Network Interface Card), a modem, etc., and connects the recording material supplying device 100, the recording material conveying device 400, the image forming device 200, and the post-processing device 300 to a communication network such as a LAN (Local Area Network) or a WAN (Wide Area Network), and transmits and receives various data between external information devices (e.g., client devices).

[0046] The operation display unit 220 is composed of a touch panel or the like having a pressure-sensitive or capacitance-type operation unit (touch sensor) with transparent electrodes arranged in a grid pattern on a display unit such as an LCD (Liquid Crystal Display) or an organic EL (Electro Luminescence) display, and functions as a display unit and an operation unit. The display unit displays various operation screens according to a display control signal input from the control unit 90. The operation unit accepts various input operations by the user and outputs operation signals to the control unit 90.

[0047] The scanner 230 optically scans an original placed on a contact glass and reads the original image by forming an image of reflected light from the original on the light receiving surface of a CCD (Charge Coupled Device) sensor. The image (analog image signal) read by the scanner 230 is subjected to predetermined image processing in the image processing unit 80.

[0048] The image processing unit 80 is composed of a circuit that performs analog-to-digital (A / D) conversion processing and a circuit that performs digital image processing. The image processing unit 80 generates digital image data by performing A / D conversion processing on an analog image signal from the scanner 230. The image processing unit 80 also analyzes a print job acquired from an external information device (e.g., a client device) and rasterizes each page of the document to generate digital image data. Then, the image processing unit 80 performs image processing such as color conversion processing, correction processing (shading correction, etc.) according to initial settings or user settings, and compression processing on the image data as necessary, and outputs the image data after image processing to the image forming unit 240.

[0049] [Functional configuration of the control unit] Next, a description will be given of the functional configuration of the control unit 90. Fig. 3 shows a functional block diagram of the control unit 90. As shown in Fig. 3, the control unit 90 has a paper feed control unit 94, a transport control unit 95, a detection control unit 96, and an image formation control unit 97.

[0050] The paper feed control unit 94 controls the supply of the recording material S from the recording material supply unit 70 to the conveying unit 50 in the recording material supplying device 100. The paper feed control unit 94 supplies the recording material S to the conveying unit 50 in accordance with the conveying control of the recording material S by the conveying control unit 95.

[0051] The conveyance control unit 95 controls the operation of the conveyance mechanism for the recording material S between and within the recording material supplying device 100, the recording material conveying device 400, the image forming device 200, and the post-processing device 300 constituting the image forming system 10. For example, the conveyance control unit 95 controls the driving of the conveyance unit 50 of the recording material supplying device 100, the first conveyance unit 51, the second conveyance unit 52, and the third conveyance unit 53 of the recording material conveying device 400, the conveyance unit 250 of the image forming device 200, and the conveyance unit 350 of the post-processing device 300, and other conveyance units of the image forming system 10, thereby controlling the conveyance of the recording material S. The conveyance control unit 95 controls the stop of driving of each driving unit, the adjustment of the timing of starting driving and the driving speed, etc., according to the conveyance conditions in accordance with the recording material characteristics of the recording material S. Through this control, the driving units are linked between the devices of the image forming system 10, and the conveyance of the recording material S in the image forming system 10 is controlled.

[0052] Furthermore, the transport control unit 95 sets transport conditions for the recording material S according to the recording material characteristics acquired by the detection control unit 96. For example, the transport control unit 95 acquires transport conditions according to the recording material characteristics from data stored in the memory unit 98 or the like. Then, the transport control unit 95 sets transport conditions for each of the components of the transport unit 50, the first transport unit 51, the second transport unit 52, the third transport unit 53, the transport unit 250, and the transport unit 350 based on the data acquired from the memory unit 98 or the like.

[0053] Furthermore, in the recording material conveying device 400, the conveying control section 95 selects the conveying path of the recording material S conveyed by the first conveying section 51 from either the second conveying section 52 or the third conveying section 53, and switches the conveying path of the recording material S at the branching section 58. Then, the conveying control section 95 controls the driving of the second conveying section 52 or the third conveying section 53 selected as the conveying path to convey the recording material S. When conveying multiple recording materials S in a print job, the conveying control section 95 conveys at least one sheet of recording material S to the second conveying section 52.

[0054] The conveyance control unit 95 drives the first conveying unit 51 and the third conveying unit 53 to convey the recording material S at a normal speed during image formation. The conveyance control unit 95 conveys the recording material S at the first conveying unit 51 and the third conveying unit 53, thereby conveying the recording material S from the recording material conveying device 400 to the image forming device 200.

[0055] Furthermore, the conveyance control unit 95 reduces the conveyance speed in the second conveying unit 52 after the entire recording material S has been conveyed to the second conveying unit 52, that is, after the rear end of the recording material S has passed the branching unit 58. Then, after the recording material S reaches the first detection unit 71 that detects the recording material characteristics, the conveyance control unit 95 conveys the recording material S at a reduced speed to a speed at which the first detection unit 71 can detect the recording material characteristics with high accuracy. Furthermore, after conveying the recording material S to a position at which the first detection unit 71 can detect the recording material characteristics, the conveyance control unit 95 may stop conveying the recording material S until detection of the recording material characteristics by the first detection unit 71 is completed. Furthermore, the conveyance control section 95 conveys the recording material S after the recording material characteristics have been detected in the second conveying section 52 , and discharges it from the first discharging section 56 to the outside of the recording material conveying device 400 .

[0056] The detection control unit 96 controls the detection of the recording material characteristics of the recording material S by the first detection unit 71 and the second detection unit 72. For example, when the recording material S is conveyed to the second conveying unit 52 in which the first detection unit 71 is provided, the detection control unit 96 instructs the first detection unit 71 to execute detection of the recording material characteristics. Based on this instruction, the first detection unit 71 starts detecting the recording material characteristics of the recording material S. In addition, the detection control unit 96 instructs the second detection unit 72 to execute detection of the recording material characteristics while the recording material S is passing through the first conveying unit 51 in which the second detection unit 72 is provided.

[0057] Furthermore, the detection control unit 96 receives various data detected by the sensors of the first detection unit 71 and the second detection unit 72, and calculates the recording material characteristics of the recording material S based on this data. For example, in a configuration in which the image forming system 10 includes a plurality of first detection units 71, the detection control unit 96 combines the data acquired from the plurality of first detection units 71 and calculates the recording material characteristics of the recording material S. In a configuration in which the image forming system 10 includes a plurality of second detection units 72, the detection control unit 96 combines the data acquired from the plurality of second detection units 72 and calculates the recording material characteristics of the recording material S.

[0058] The image formation control unit 97 controls the image forming operation in the image forming unit 240 of the image forming apparatus 200. The image formation control unit 97 also sets image forming conditions according to the recording material characteristics acquired by the detection control unit 96. For example, the image formation control unit 97 acquires the image forming conditions according to the recording material characteristics from data stored in the storage unit 98 or the like. Then, the image formation control unit 97 sets operating conditions for each component of the image forming unit 240 based on the data acquired from the storage unit 98 or the like. Then, according to the set operating conditions, the image formation control unit 97 controls the operation of each component of the image forming unit 240 to form an image on the recording material S based on the image data.

[0059] [Detection of recording material characteristics] Next, a description will be given of a process for detecting recording material characteristics in the image forming system 10. A flowchart of the process for detecting recording material characteristics is shown in Fig. 4. Note that the flowchart shown in Fig. 4 mainly describes the conveyance of the recording material in the recording material conveying device 400 and the detection of the recording material characteristics.

[0060] First, in the image forming system 10, the control section 90 conveys the recording material S from the conveying section 50 of the recording material supplying device 100 to the first conveying section 51 of the recording material conveying device 400 (step S101). Next, the control section 90 determines whether or not a measurement mode is set in response to an instruction from a user or the like so that the recording material characteristics of the recording material S are detected by the first detection section 71 (step S102).

[0061] If measurement is set at the first detection unit 71 (Yes in step S102), the transport control unit 95 switches the transport path of the recording material S transported to the first transport unit 51 at the branching unit 58 and transports the recording material S to the second transport unit 52 (step S103). Then, the detection control unit 96 detects the recording material characteristics of the recording material S transported to the second transport unit 52 using the first detection unit 71 (step S104). Then, during the period when the first detection unit 71 is detecting the recording material characteristics, the transport control unit 95 stops transporting the recording material S in the second transport unit 52 or transports it at a low speed. In addition, after the recording material S passes through the branching unit 58, the transport control unit 95 may transport the next recording material S from the recording material supply device 100 to the first transport unit 51 while the first detection unit 71 is detecting the recording material characteristics.

[0062] If measurement by the first detection unit 71 is not set (No in step S102), the control unit 90 determines whether the measurement mode is set to detect the recording material characteristics of the recording material S by the second detection unit 72 at the instruction of a user or the like (step S105). When the measurement by the second detection unit 72 is set (Yes in step S105), the detection control unit 96 detects the recording material characteristics of the recording material S transported to the first transport unit 51 using the second detection unit 72 (step S106). At this time, while the second detection unit 72 is detecting the recording material characteristics, it is preferable that the transport control unit 95 transports the recording material S without changing the transport speed in the first transport unit 51.

[0063] Next, the detection control unit 96 determines whether the recording material characteristics of the recording material S detected by the second detection unit 72 are within an appropriate range set as an image forming condition (step S107). If measurement at the second detection unit 72 is not set (No in step S105), or if the recording material characteristics of the recording material S are within the appropriate range (Yes in step S107), the conveying control unit 95 switches the conveying path at the branching unit 58 and conveys the recording material S conveyed by the first conveying unit 51 to the third conveying unit 53 (step S108). Then, the conveyance control unit 95 conveys the recording material S conveyed by the third conveying unit 53 from the discharge opening 57 (step S109). By conveying the recording material S from the discharge opening 57, the conveyance control unit 95 conveys the recording material S from the recording material conveying device 400 to the image forming apparatus 200.

[0064] If the recording material characteristics of the recording material S are not within the appropriate range (No in step S107), the conveying control unit 95 switches the conveying path of the recording material S conveyed to the first conveying unit 51 at the branching unit 58 and conveys the recording material S to the second conveying unit 52 (step S110).

[0065] After the recording material characteristics of the recording material S are detected by the first detection unit 71 in step S104, or after the recording material S is transported to the second transport unit 52 in step S110, the transport control unit 95 discharges the recording material S transported by the second transport unit 52 from the first discharge unit 56 (step S111). After the recording material S is discharged from the first discharge portion 56 or the discharge port 57, the process according to this flowchart ends.

[0066] In the process according to the above-described flowchart, the recording material S whose recording material characteristics are to be detected by the first detection unit 71 is transported from the first transport unit 51 to the second transport unit 52, and the recording material characteristics are detected by the first detection unit 71. Then, the recording material S whose recording material characteristics have been detected by the first detection unit 71 is discharged from the first discharge unit 56 of the recording material transport device 400 without being transported to the image forming device 200. In this way, the recording material S that has been charged by electrical detection in the first detection unit 71 or the recording material S that has been folded or the like due to contact can be discharged outside the image forming system 10 without being transported to the image forming unit 240 of the image forming device 200.

[0067] This prevents the occurrence of transport problems (jams) in the image forming section 240 due to the charged recording material S sticking to the transport section, and inhibits the obstruction of charge transfer in the electrophotographic process, thereby preventing a decrease in the reliability of image formation. Furthermore, it is possible to prevent occurrence of transport problems such as jams caused by the recording material being deformed by an external force when detecting the recording material characteristics.

[0068] Furthermore, for recording material S whose recording material characteristics are not detected by first detection unit 71, second detection unit 72 disposed in first conveying unit 51 detects the recording material characteristics. If the recording material characteristics detected by second detection unit 72 are not within a predetermined range, this recording material S is conveyed to second conveying unit 52 and discharged from first discharge unit 56. In particular, if the recording material characteristics such as paper type, thickness, and charge rate are outside the predetermined range, the recording material S is not conveyed to image forming unit 240 but is discharged to the outside, thereby suppressing the occurrence of conveyance failure (jam) and deterioration of reliability due to inhibition of charge transfer in the electrophotographic process.

[0069] 2. Second embodiment of recording material conveying device and image forming system Next, a second embodiment of the recording material conveying device and image forming system will be described. Note that the image forming system of the second embodiment differs from the image forming system of the first embodiment only in the configuration of the recording material conveying section from the recording material conveying device to the post-processing device and the arrangement of the detection section. Therefore, only the configuration related to the recording material conveying section and the detection section will be described, and the description of the same configuration as the first embodiment will be omitted.

[0070] The configuration of a recording material conveying device and an image forming system according to the second embodiment is shown in Fig. 5. As shown in Fig. 5, an image forming system 20 is composed of a recording material supplying device 100, a recording material conveying device 500, an image forming device 200A, and a post-processing device 300A. In the image forming system 20 shown in Fig. 5, the recording material supplying device 100 has the same configuration as in the first embodiment described above.

[0071] [Recording material transport device] The recording material conveying device 500 includes an entrance 55 through which the recording material S is conveyed into the recording material conveying device 500, a first conveying section 51A that conveys the recording material S, and an exit 57 through which the recording material S is conveyed from the first conveying section 51A to the image forming device 200A. The first conveying section 51A also includes a first detection section 71 and a second detection section 72 for detecting the recording material characteristics of the recording material S.

[0072] In the first conveying section 51A, the second detection section 72 is disposed upstream in the recording material conveying direction from the first detection section 71. Furthermore, a plurality of the first detection sections 71 and the second detection sections 72 are provided on the first conveying section 51A. The order in which the first detection sections 71 and the second detection sections 72 are disposed does not matter, and either one may be disposed on the upstream side, and the first detection sections 71 and the second detection sections 72 may be mixed. It is preferable that the first conveying section 51A is configured to have a length from the entrance 55 to the exit 57 such that the conveying distance of the recording material S is the shortest.

[0073] [Image forming device] The image forming apparatus 200A can have the same configuration as that of the above-described first embodiment, except for the configuration of the recording material transport path.

[0074] The image forming apparatus 200A has a part of the first conveying section 51A, a second conveying section 52A branched off from the first conveying section 51A downstream in the recording material conveying direction, and a third conveying section 53A. The image forming apparatus 200A further has a branching section 58 where the second conveying section 52A and the third conveying section 53A branch off from the first conveying section 51A, and a junction section 59 where the branched third conveying section 53A rejoins the second conveying section 52A.

[0075] The second conveying section 52A constitutes a conveying path for conveying the recording material S out of the image forming apparatus 200A without passing through the image forming section 240. That is, the second conveying section 52A includes a conveying path from the branching section 58 in the image forming apparatus 200A to the branching section 354 in the post-processing device 300A. Therefore, the recording material S conveyed to the second conveying section 52A is conveyed from the first conveying section 51A through the branching section 58 to the second conveying section 52A, and further through the junction section 59 to be conveyed to the post-processing device 300A.

[0076] The third conveying section 53A constitutes a conveying path that passes the recording material S to the image forming section 240. The third conveying section 53A includes a conveying path from the branching section 58 to the junction section 59 in the image forming device 200. For this reason, the recording material S conveyed to the third conveying section 53A is conveyed from the first conveying section 51A through the branching section 58 to the third conveying section 53A, passes through the image forming section 240 and the fixing section 248 by the third conveying section 53A, and is then conveyed from the third conveying section 53A to the second conveying section 52A at the junction section 59 and conveyed to the post-processing device 300A.

[0077] [Post-processing device] The configuration of the post-processing device 300A can be the same as that of the first embodiment described above, except for the configurations of the recording material transport path and the paper discharge unit. The post-processing device 300A includes a part of the second conveying section 52A, a fourth conveying section 353 branched off from the second conveying section 52A downstream in the recording material conveying direction, a fifth conveying section 350, and a branching section 354 where the fourth conveying section 353 and the fifth conveying section 350 branch off from the second conveying section 52A. The post-processing device 300A also includes a first discharge section 355 to which the recording material S conveyed by the fourth conveying section 353 is discharged, and a paper discharge tray 356 on which the recording material S discharged from the first discharge section 355 is stacked. The post-processing device 300A further includes a second discharge section 351 to which the recording material S conveyed by the fifth conveying section 350 is discharged, and a paper discharge tray 352 on which the recording material S discharged from the second discharge section 351 is stacked.

[0078] In the post-processing device 300A, the recording material S conveyed by the second conveying section 52A, i.e., the recording material S that has not passed through the image forming section 240, is conveyed from the branching section 58 to the fourth conveying section 353. Then, the recording material S conveyed by the fourth conveying section 353 is discharged to the first discharge section 355.

[0079] In the post-processing device 300A, the recording material S that has been conveyed through the third conveying section 53A and passed through the image forming section 240 is conveyed to the fifth conveying section 350. Then, the recording material S conveyed through the fifth conveying section 350 is discharged to the second discharge section 351.

[0080] [Functional configuration of the control unit] The functional configuration of the control unit 90 in the image forming system 20 can be the same as that of the first embodiment described above.

[0081] The conveyance control unit 95 conveys the recording material S at the first conveyance unit 51A in the recording material conveying device 500. Then, in the image forming apparatus 200A, the conveyance control unit 95 selects the conveyance path of the recording material S from the first conveyance unit 51A to either the second conveyance unit 52A or the third conveyance unit 53A, and switches the conveyance path of the recording material S at the branching unit 58. Then, the conveyance control unit 95 controls the driving of the second conveyance unit 52A or the third conveyance unit 53A selected as the conveyance path, and conveys the recording material S. Furthermore, in the post-processing device 300A, the conveyance control unit 95 selects the conveyance path of the recording material S from the second conveyance unit 52A to either the fourth conveyance unit 353 or the fifth conveyance unit 350, and switches the conveyance path of the recording material S at the branching unit 354. Then, the control unit 352 controls the driving of the fourth conveying unit 353 or the fifth conveying unit 350 selected as the conveying path, conveys the recording material S, and discharges the recording material S from the first discharge unit 355 or the second discharge unit 351.

[0082] Furthermore, the conveyance control section 95 switches the conveyance path at the branching section 58 in the image forming apparatus 200A for the recording material S whose recording material characteristics have been detected by the first detection section 71, and conveys the recording material S to the second conveyance section 52A. On the other hand, the conveyance control section 95 switches the conveyance path at the branching section 58 in the image forming apparatus 200A for the recording material S whose recording material characteristics have not been detected by the first detection section 71, and conveys the recording material S to the third conveyance section 53A. As a result, the conveyance control section 95 conveys the recording material S, whose recording material characteristics have been detected by the first detection section 71, through a conveyance path within the image forming apparatus 200A that bypasses the image forming section 240 without passing through the image forming section 240. In this configuration, the recording material, whose recording material characteristics have been detected by the first detection section 71, does not pass through the image forming section 240, so that a decrease in the reliability of the image forming system 20 can be suppressed.

[0083] Furthermore, the conveyance control section 95 also switches the conveyance path at the branching section 58 in the image forming apparatus 200A and conveys the recording material S, whose recording material characteristics are detected to be outside the appropriate range by the second detection section 72, to the second conveyance section 52A. As a result, within the image forming apparatus 200A, the recording material S, whose recording material characteristics are outside the appropriate range, is conveyed on a conveyance path that bypasses the image forming section 240. As a result, the recording material outside the appropriate range does not pass through the image forming section 240, and a decrease in the reliability of the image forming system 20 can be suppressed.

[0084] [Detection of recording material characteristics] Next, a description will be given of a process for detecting recording material characteristics in the image forming system 20. A flowchart of the process for detecting recording material characteristics is shown in Fig. 6. Note that the flowchart shown in Fig. 6 mainly describes the conveyance of the recording material in the image forming system 20 and the detection of recording material characteristics.

[0085] First, in the image forming system 20, the control section 90 conveys the recording material S from the conveying section 50 of the recording material supplying device 100 to the first conveying section 51A of the recording material conveying device 500 (step S201). Next, the control unit 90 determines whether or not a measurement mode is set in response to an instruction from a user or the like so that the recording material characteristics of the recording material S are detected by the first detection unit 71 (step S202).

[0086] If measurement is set in the first detection unit 71 (Yes in step S202), the detection control unit 96 uses the first detection unit 71 to detect the recording material characteristics of the recording material S being transported to the first transport unit 51A (step S203).

[0087] If measurement by the first detection unit 71 is not set (No in step S202), the control unit 90 determines whether the measurement mode is set to detect the recording material characteristics of the recording material S by the second detection unit 72 at the instruction of a user or the like (step S204). If measurement is set in the second detection unit 72 (Yes in step S204), the detection control unit 96 uses the second detection unit 72 to detect the recording material characteristics of the recording material S being transported to the first transport unit 51A (step S205).

[0088] Next, the detection control unit 96 determines whether the recording material characteristics of the recording material S detected by the second detection unit 72 are within an appropriate range set as an image forming condition (step S206). If measurement by the second detection unit 72 is not set (No in step S204), or if the recording material characteristics of the recording material S are within the appropriate range (Yes in step S206), the conveying control unit 95 switches the conveying path at the branching unit 58 for the recording material S conveyed by the first conveying unit 51A in the image forming device 200A, and conveys the recording material S to the third conveying unit 53A (step S207). Then, the conveyance control section 95 conveys the recording material S conveyed by the third conveyance section 53A to the image forming section 240, and the image formation control section 97 drives the image forming section 240 to form an image on the recording material S (step S208).

[0089] Next, the conveying control unit 95 conveys the recording material S conveyed by the third conveying section 53A in the image forming device 200A from the junction 59 to the second conveying section 52A, and then switches the conveying path at the branching section 354 in the post-processing device 300A to convey the recording material S from the second conveying section 52A to the fifth conveying section 350 (step S209). Then, the conveyance control unit 95 discharges the recording material S conveyed by the fifth conveying unit 350 from the second discharge unit 351 (step S210). By discharging the recording material S from the second discharge unit 351, the conveyance control unit 95 discharges the recording material S on which the image has been formed from the image forming system 20.

[0090] If the recording material characteristics of the recording material S are not within the appropriate range (No in step S206), or after the first detection unit 71 detects the recording material characteristics of the recording material S in step S203, the conveying control unit 95 switches the conveying path at the branching unit 58 for the recording material S conveyed by the first conveying unit 51A in the image forming device 200A, and conveys the recording material S to the second conveying unit 52A (step S211). Then, the conveying control unit 95 causes the recording material S conveyed by the second conveying section 52A in the image forming device 200A to pass through the junction 59, and switches the conveying path at the branching section 354 in the post-processing device 300A to convey the recording material S from the second conveying section 52A to the fourth conveying section 353 (step S212). Then, the conveyance control unit 95 discharges the recording material S conveyed by the fourth conveying unit 353 from the first discharge unit 355 (step S213). By discharging the recording material S from the first discharge unit 355, the conveyance control unit 95 discharges the recording material S on which no image has been formed from the image forming system 20. After the recording material S is discharged from the first discharge portion 355 or the second discharge portion 351, the process according to this flowchart ends.

[0091] In the process according to the above-mentioned flow chart, the first detection unit 71 disposed in the first conveying unit 51A detects the recording material characteristics of the recording material S for which the first detection unit 71 has set the detection of the recording material characteristics. The recording material S for which the first detection unit 71 has performed the detection of the recording material characteristics is conveyed to the second conveying unit 52A, so that the recording material S is conveyed inside the image forming device 200A without passing through the image forming unit 240, and is discharged from the first discharge unit 355 of the post-processing device 300A. This allows the recording material S that has been charged by electrical detection in the first detection unit 71 or the recording material S that has been folded or the like due to contact to be discharged outside the image forming system 20 without being conveyed to the image forming unit 240 of the image forming device 200A.

[0092] This makes it possible to suppress the occurrence of transport problems (jams) in the image forming system 20 due to the charged recording material S sticking to the transport section in the image forming section 240, as well as the obstruction of charge transfer in the electrophotographic process, thereby suppressing a decrease in the reliability of image formation. Furthermore, it is possible to prevent occurrence of transport problems such as jams caused by the recording material being deformed by an external force when detecting the recording material characteristics.

[0093] Furthermore, for recording material S whose recording material characteristics are not detected by first detection unit 71, second detection unit 72 disposed in first conveying section 51A detects the recording material characteristics. Then, when the recording material characteristics detected by second detection unit 72 are not within a predetermined range, this recording material S is conveyed to second conveying section 52A, where it is conveyed through image forming device 200A without passing through image forming section 240, and is discharged from first discharge section 355 of post-processing device 300A. This makes it possible to suppress the occurrence of conveyance failure (jam) and deterioration of reliability due to obstruction of charge transfer in the electrophotographic process in image forming system 20.

[0094] 3. Third embodiment of recording material conveying device and image forming system Next, a recording material conveying device and an image forming system according to a third embodiment will be described. Note that the image forming system according to the third embodiment differs from the image forming system according to the second embodiment only in the arrangement of the first detection unit. Therefore, only the configuration related to the first detection unit will be described, and the description of the same configuration as the first and second embodiments will be omitted.

[0095] The configuration of a recording material conveying device and an image forming system according to the third embodiment is shown in Fig. 7. As shown in Fig. 7, an image forming system 30 is composed of a recording material supplying device 100, a recording material conveying device 600, an image forming apparatus 200B, and a post-processing device 300A. In the image forming system 30 shown in Fig. 5, the recording material supplying device 100 and the post-processing device 300A have the same configuration as those in the second embodiment. Moreover, the recording material conveying device 600 and the image forming apparatus 200B have the same configuration as those in the second embodiment, except for the arrangement of a first detection unit 71.

[0096] [First detection section] 7, the first detection unit 71 is disposed in the second conveying unit 52A in the image forming apparatus 200B. Therefore, in the recording material conveying device 600, only the first conveying unit 51A and the second detection unit 72 are disposed. Furthermore, the image forming apparatus 200B has a second conveying section 52A branched off from the first conveying section 51A at a branching section 58, and a third conveying section 53, downstream of the first conveying section 51A in the recording material conveying direction. In the image forming apparatus 200B, a first detection section 71 is disposed in the second conveying section 52A.

[0097] [Functional configuration of the control unit] The functional configuration of the control unit 90 in the image forming system 30 can be the same as that of the first and second embodiments described above.

[0098] The conveyance control unit 95 conveys the recording material S by the first conveyance unit 51A in the recording material conveying device 600. Then, the recording material characteristics of the recording material S are detected by the second detection unit 72 disposed in the first conveyance unit 51A.

[0099] Furthermore, the conveyance control section 95 switches the conveyance path at the branching section 58 in the image forming apparatus 200B for the recording material S, whose recording material characteristics are to be detected by the first detection section 71, and conveys the recording material S to the second conveyance section 52A. Then, the first detection section 71 disposed in the second conveyance section 52A detects the recording material characteristics of the recording material S. On the other hand, the conveyance control section 95 switches the conveyance path at the branching section 58 in the image forming apparatus 200B for the recording material S whose recording material characteristics are not detected by the first detection section 71, and conveys the recording material S to the third conveyance section 53A.

[0100] As a result, the conveyance control section 95 conveys the recording material S, whose recording material characteristics are detected by the first detection section 71, through a conveyance path that bypasses the image forming section 240 within the image forming apparatus 200B without passing through the image forming section 240. In this configuration, the recording material, whose recording material characteristics are detected by the first detection section 71, does not pass through the image forming section 240, so that a decrease in the reliability of the image forming system 20 can be suppressed.

[0101] Furthermore, the conveyance control section 95 also switches the conveyance path at the branching section 58 in the image forming apparatus 200B and conveys the recording material S, whose recording material characteristics are detected to be outside the appropriate range by the second detection section 72, to the second conveyance section 52A. As a result, in the image forming apparatus 200B, the recording material S, whose recording material characteristics are outside the appropriate range, is conveyed on a conveyance path that bypasses the image forming section 240. As a result, the recording material outside the appropriate range does not pass through the image forming section 240, and a decrease in the reliability of the image forming system 20 can be suppressed.

[0102] The present invention is not limited to the configurations described in the above-mentioned embodiments, and various modifications and variations are possible without departing from the scope of the present invention. [Explanation of symbols]

[0103] 10,20,30 Image forming system, 50,250 Conveying section, 51,51A First conveying section, 52,52A Second conveying section, 53,53A Third conveying section, 54 Conveying roller, 55 Inlet, 56,355 First discharge section, 57 Outlet, 58,354 Branching section, 59 Junction section, 70 Recording material supplying section, 71 First detection section, 72 Second detection section, 80 Image processing section, 90 Control section, 91 CPU, 92 ROM, 93 RAM, 94 Paper feed control section, 95 Conveying control section, 96 Detection control section, 97 Image forming control section, 98 Memory section, 99 Communication section, 100 Recording material supplying device, 200,200A,200B Image forming apparatus, 220 Operation display section, 230 Scanner, 240 Image forming section, 241Y, 241M, 241C, 241K photoconductor drum, 242Y, 242M, 242C, 242K charging section, 243Y, 243M, 243C, 243K exposure section, 244Y, 244M, 244C, 244K developing section, 245Y, 245M, 245C, 245K primary transfer roller, 246 intermediate transfer belt, 247 secondary transfer roller, 248 fixing section, 300, 300A post-processing device, 350 fifth conveying section, 351 second discharge section, 352, 356 discharge tray, 353 fourth conveying section, 400, 500, 600 recording material conveying device

Claims

1. a conveying path for conveying the recording material supplied from the recording material supplying unit to the image forming unit; a branch path that branches off from the conveying path and conveys the recording material without passing through the image forming unit; a first detection unit disposed on the branch path and detecting a value corresponding to a recording material characteristic of the recording material after the branch; a second detection unit that is disposed on the conveying path upstream of a branching portion of the branching path and detects a value corresponding to a recording material characteristic of the recording material; Equipped with Recording material transport device.

2. the transport path includes a first transport section that transports the recording material supplied from the recording material supply section, and a third transport section that transports the recording material downstream of the branching section so as to transport the recording material via the image forming section, The branch path includes a second conveying section that is branched from the first conveying section and is configured to convey the recording material without passing through the image forming section. The recording material transport device according to claim 1 .

3. The branch path is a path through which the recording material can be discharged. The recording material transport device according to claim 1 .

4. While the first detection unit detects a value corresponding to the recording material characteristic of the first recording material in the second conveying unit, the first conveying unit and the third conveying unit convey a second recording material. The recording material transport device according to claim 2 .

5. While the first detection unit is detecting a value corresponding to the recording material characteristic, the second transport unit stops transporting the recording material or reduces a transport speed of the recording material. The recording material transport device according to claim 2 .

6. The second detection unit detects a value corresponding to the recording material characteristic without decreasing a conveying speed of the recording material. The recording material transport device according to claim 1 .

7. In a job in which a plurality of recording materials are conveyed, the first detection unit detects a value corresponding to the recording material characteristic in the second conveying unit only for some of the recording materials. The recording material transport device according to claim 2 .

8. The second conveying section has a first discharge section that discharges the recording material after the first detection section detects a value corresponding to a recording material characteristic. The recording material transport device according to claim 2 .

9. A conveying distance of the recording material of the second conveying section is equal to or longer than a long side of a maximum size of a standard form that can be conveyed, downstream of the branching section in a conveying direction of the recording material. The recording material transport device according to claim 2 .

10. The first detection unit detects an electrical resistance value of the recording material as a value corresponding to the recording material characteristic. The recording material transport device according to claim 1 .

11. The first detection unit detects stiffness of the recording material as a value corresponding to the recording material characteristic. The recording material transport device according to claim 1 .

12. The second detection unit detects a value corresponding to the recording material characteristic without contacting the recording material. The recording material transport device according to claim 1 .

13. The second detection unit detects a value corresponding to the recording material characteristic without charging the recording material. The recording material transport device according to claim 1 .

14. An image forming system having an image forming unit that forms an image on a recording material, a conveying path for conveying the recording material supplied from a recording material supplying unit to the image forming unit; a branch path that branches off from the conveying path and conveys the recording material without passing through the image forming unit; a first detection unit disposed on the branch path and detecting a value corresponding to a recording material characteristic of the recording material after the branch; a second detection unit that is disposed upstream of the branching point of the branching path in the conveying path and detects a value corresponding to a recording material characteristic of the recording material; Image forming system.

15. the transport path includes a first transport section that transports the recording material supplied from the recording material supply section, and a third transport section that transports the recording material downstream of the branching section so as to transport the recording material via the image forming section, The branch path includes a second conveying section that is branched from the first conveying section and is configured to convey the recording material without passing through the image forming section. The imaging system of claim 14.

16. The second conveying section has a first discharge section that discharges the recording material after the first detection section detects a value corresponding to a recording material characteristic. The imaging system of claim 15.

17. The transport path of the recording material is selected from the second transport section and the third transport section based on a value corresponding to the recording material characteristic detected by the second detection section. The imaging system of claim 15.

18. a junction where the second conveying section and the third conveying section join together downstream of the image forming section in the conveying direction of the recording material, and the recording material is discharged downstream of the junction in the conveying direction of the recording material. The imaging system of claim 15.

19. a second discharge portion that discharges the recording material after branching again downstream of the junction in the recording material conveying direction; 20. The imaging system of claim 18.

20. The first detection unit detects an electrical resistance value of the recording material as a value corresponding to the recording material characteristic. The imaging system of claim 14.

21. The first detection unit detects a stiffness of the recording material as a value corresponding to the recording material characteristic. The imaging system of claim 14.

22. The second detection unit detects a value corresponding to the recording material characteristic without contacting the recording material. The imaging system of claim 14.

23. The second detection unit detects a value corresponding to the recording material characteristic without charging the recording material. The imaging system of claim 14.

Images