Recording material determination device, recording material determination method, program, and image forming apparatus

Abstract

To accurately determine coincidence or noncoincidence of a recording material without causing reduction of productivity during image formation.SOLUTION: A recording material determination device 1 comprises: a conveyance unit 6A that conveys recording materials 25 on a conveyance path 5; detection units 8a-8f that are installed on the midway of the conveyance path 5 and that detect characteristic values of the currently conveyed recording materials 25; and a control unit that controls driving of the conveyance unit 6A, and stops a first recording material 25 of the recording materials 25 at the detection units 8a-8f while not stopping a second recording material 25 conveyed after the first recording material 25 at the detection units 8a-8f. The control unit determines whether the second recording material 25 has changed with respect to the first recording material 25 on the basis of the first characteristic value detection result of the first recording material 25 detected by the detection units 8a-8f and the second characteristic value detection result of the second recording material 25 detected by the detection units 8a-8f.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a recording material determination device, a recording material determination method, a program, and an image forming apparatus.

Background Art

[0002] Conventionally, in image forming apparatuses such as copiers, printers, and multifunctional devices, information regarding the recording material stored in the paper feed tray is registered in advance in the controller, and based on the information registered in advance in this controller, the timing of conveying the recording material and the timing of forming an image on the recording material are determined. Therefore, if the information of the recording material registered in advance in the controller is different from the actual recording material sent out from the paper feed tray in the image forming apparatus, a deviation occurs in the timing of conveying the recording material and the timing of forming an image on the recording material. This deviation in the timing of conveying the recording material in the image forming apparatus causes problems such as paper jams and deformation of the recording material. Further, the deviation in the timing of forming an image on the recording material causes a problem of deterioration of image quality.

[0003] Therefore, conventionally known image forming apparatuses have installed a media sensor (detection means) in the middle of the conveyance path of the recording material, detect the characteristic values of the recording material conveyed along the conveyance path by the media sensor, and use the characteristic values of the recording material to discriminate the type, basis weight, or brand of the recording material. Then, this conventional image forming apparatus compares the discrimination result of the recording material with the information of the recording material registered in advance in the controller, and when the discrimination result of the recording material and the registered information of the recording material do not match, warns the user via display means (for example, a liquid crystal display panel), and avoids the occurrence of problems caused by the difference between the information of the recording material registered in advance in the controller and the actual recording material sent out from the paper feed tray. Further, considering that a plurality of types of recording materials are mixed in the paper feed tray, this conventional image forming apparatus performs type detection on all of the recording materials sent out from the paper feed tray to the conveyance path, and determines whether or not the subsequent recording materials have changed based on the type of the first recording material (see Patent Document 1).

Prior Art Documents

[0004] [Patent Document 1] Japanese Patent Publication No. 2015-160737 [Overview of the project] [Problems that the invention aims to solve]

[0005] However, in conventional image forming machines, all recording material sent from the paper tray to the transport path is stopped at the detection unit, and the characteristic values ​​of the recording material are detected by a media sensor installed in the detection unit. While this allows for high-precision detection of the characteristic values ​​of the recording material, it results in a decrease in productivity during image formation (a decrease in printing speed (sheets / minute)) because each sheet of recording material is stopped at the detection unit.

[0006] Furthermore, in conventional image forming apparatuses, the characteristic values ​​of the recording material as it moves along the transport path are detected by a media sensor installed in the detection unit without stopping the recording material after it is fed from the paper tray onto the transport path. In such cases, the orientation of the recording material changes depending on the transport conditions (a deviation occurs from the reference orientation of the recording material), and the detection position of the recording material may deviate from the reference detection position of the detection unit. In such conventional image forming apparatuses, if a detection error occurs in the detection value of the first recording material, the detection value including this detection error is used as a reference to determine whether it matches or does not match the subsequent recording material. This leads to a problem where the accuracy of determining whether the recording materials match or not deteriorates.

[0007] The object of the present invention is to provide a recording material determination device, a recording material determination method, a program for the recording material determination device, and an image forming apparatus that can accurately determine whether recording materials match or not without causing a decrease in productivity during image formation. [Means for solving the problem]

[0008] The recording material determination device according to claim 1 is A transport unit that transports recording material along a transport path, A detection unit is installed in the middle of the transport path to detect characteristic values ​​of the recording material while it is being transported. The system includes a control unit that controls the drive of the transport unit, stops the first recording material among the recording materials at the detection unit, and does not stop the second recording material, which is transported after the first recording material, at the detection unit. The control unit receives the first characteristic value detection result of the first recording material detected by the detection unit and the second characteristic value detection result of the second recording material detected by the detection unit. By comparing these, it is determined whether the second characteristic value detection result falls within a predetermined threshold based on the first characteristic value detection result. , determine whether the second recording material has changed relative to the first recording material. death, The control unit sets the predetermined threshold for determining whether the first recording material and the second recording material have changed to a smaller value as the thickness of the first recording material increases.

[0009] Furthermore, claims 12 The recording material determination method of the described invention is: By the transport unit A transport step that transports the recording material along the transport path, A detection step in which a detection unit installed in the middle of the transport path detects the characteristic values ​​of the recording material being transported, The system includes a control step that controls the drive of the transport unit, stops the first recording material among the recording materials at the detection unit, and does not stop the second recording material, which is transported after the first recording material, at the detection unit. The control step involves the detection of a first characteristic value of the first recording material detected by the detection unit and the detection of a second characteristic value of the second recording material detected by the detection unit. By comparing these, and determining whether the second characteristic value detection result falls within a predetermined threshold based on the first characteristic value detection result, Determining whether the second recording material has changed relative to the first recording material. death, The control step involves setting a predetermined threshold for determining whether the first recording material and the second recording material have changed to a smaller value as the thickness of the first recording material increases.

[0010] Claim 13 The program of the invention described is Claim 12 The recording material determination method described above is executed by a computer.

[0011] Claim 14 The image forming apparatus of the invention described above is Claim 1 ~ 11The recording material determination device according to any one of the following, and an image forming unit that forms an image on the recording material.

Advantages of the Invention

[0012] According to the present invention, it is possible to accurately determine whether the recording materials match or do not match without causing a decrease in productivity during image formation.

Brief Description of the Drawings

[0013] [Figure 1] It is a configuration diagram of an image forming apparatus including a recording material determination device according to a first embodiment of the present invention. [Figure 2] It is a diagram showing a part of the recording material determination device in FIG. 1 in an enlarged manner. [Figure 3] It is a functional block diagram showing a control structure of an image forming apparatus including a recording material determination device. [Figure 4] It is a flowchart showing an operating state of the recording material determination device. [Figure 5] It is a diagram comparing and showing a case where a characteristic value of a first recording material is detected when the first recording material is stopped by a detection unit and a case where the characteristic value is detected without the first recording material being stopped by the detection unit. [Figure 6] It is a diagram showing the determination of the type of recording material based on a discrimination algorithm. [Figure 7] It is a diagram for explaining a determination threshold value in a control unit. [Figure 8] It is a flowchart showing an operating state of the recording material determination device according to Modification 1. [Figure 9] It is a flowchart showing an operating state of the recording material determination device according to Modification 2. [Figure 10] It is a configuration diagram of an image forming apparatus including a recording material determination device according to a second embodiment of the present invention.

Modes for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

[0015] <First Embodiment> Figure 1 is a diagram showing the configuration of an image forming apparatus 2 equipped with a recording material determination device 1 according to the first embodiment of the present invention.

[0016] As shown in Figure 1, the image forming apparatus 2 is configured such that sheet-like recording material 25 loaded in a paper feed tray (paper feed section) 3 is fed one sheet at a time to a transport path 5 by a paper feed roller 4, and the recording material 25 fed to the transport path 5 is transported along the transport path 5 by a transport section 6A composed of multiple transport roller pairs 6. Along the transport path 5, there are multiple detection sections 8a to 8f (as many as there are detection means 7a to 7f) that detect the characteristic values ​​(basis weight, paper thickness, etc.) of the recording material 25 using detection means 7a to 7f. Downstream of the transport direction of the recording material 25 relative to these detection sections 8a to 8f, there is an image forming section 10 that forms toner images of C (cyan), M (magenta), Y (yellow), and K (black), an intermediate transfer belt 11 to which the toner images formed by the image forming section 10 are transferred, and a secondary transfer roller 12 that secondarily transfers the toner images transferred to the intermediate transfer belt 11 to the recording material 25. The intermediate transfer belt 11 and the secondary transfer roller 12 constitute the transfer section 13 that transfers the toner image onto the recording material 25.

[0017] The recording material 25 onto which the toner image has been transferred is fed to the fuser unit 14, where the toner image is fixed by heating and pressurizing. In the case of a single-sided printing job, the recording material 25 that has passed through the fuser unit 14 is transported along the transport path 5 (5a) by the transport roller pair 6 and sequentially discharged onto the output tray 15. In the case of a double-sided printing job, the recording material 25 that has passed through the fuser unit 14 is transported to the double-sided printing transport path 16, where it is reversed, transported sequentially to the transfer unit 13 and the fuser unit 14, and then discharged onto the output tray 15 by the transport roller pair 6. If post-processing such as stapling is to be performed on the recording material 25 that has passed through the fuser unit 14, the transport path 5 (5b) of the recording material 25 is switched, the fixed recording material 25 is fed to the post-processing device 17, and the recording material 25 after post-processing is discharged onto the output tray (output unit) 18.

[0018] Furthermore, as shown in Figure 1, the image forming apparatus 2 has a document reading device (image reading unit) 21 installed on top of the main body 20 of the image forming apparatus, and an operation unit 23 equipped with a display means 22 (for example, a liquid crystal display panel). The operation unit 23 is equipped with a numeric keypad (input means) 24 for pre-setting various data in the RAM 28B or storage unit 31 of the control unit 28, and a liquid crystal display panel (display means 22) that enables character input and can display various data (see Figure 3). Note that the operation unit 23 is not limited to one installed on the main body 20 of the image forming apparatus, but may be an external PC or external information terminal device connected via the communication unit 32 (see Figure 3).

[0019] Figure 2 is an enlarged view of a part of the recording material determination device 1 shown in Figure 1. As shown in Figures 1 and 2, the recording material determination device 1 includes a plurality of transport roller pairs 6 that transport the recording material 25 fed from the paper tray 3 along the transport path 5, and a driving means (gears, belt, etc.) 27 that transmits the rotation of a motor 26 to these transport roller pairs 6. As shown in Figure 2, the motor 26 is driven and controlled by a control unit 28. The recording material 25 transported by the plurality of transport roller pairs 6 to the detection unit 8a (8b to 8f) has its characteristic values ​​detected by detection means 7a (7b to 7f) located in the detection unit 8a (8b to 8f).

[0020] Figure 3 is a functional block diagram showing the control structure of the image forming apparatus 2 equipped with the recording material determination device 1. Figure 4 is a flowchart showing the operating state of the recording material determination device 1.

[0021] As shown in Figure 3, the control unit 28 is a computer equipped with, for example, a CPU 28A, RAM 28B, ROM 28C, etc. In this embodiment, the CPU 28A reads various processing programs stored in the ROM 28C in response to operation signals input from the operation unit 23 or instruction signals received via the communication unit 32, loads them into the work area of ​​the RAM 28B, and, in cooperation with the various processing programs loaded into the RAM 28B, comprehensively controls the operation of the image forming apparatus 2.

[0022] In explaining the flowchart in Figure 4, the first recording material 25 sent from the paper feed tray 3 to the transport path 5 will be referred to as the first recording material 25, and any recording material 25 sent from the paper feed tray 3 to the transport path 5 after the first recording material 25 will be referred to as the second recording material 25. First, when a print job is started, in the recording material determination device 1 according to this embodiment, if the control unit 28 determines that there is no recording material information for the first recording material 25 in the paper feed tray 3 (step S1; YES), it transports the first recording material 25 to each detection unit 8a to 8f located along the transport path 5, and stops the first recording material 25 at each detection unit 8a to 8f. The control unit 28 then controls the operation of the transport roller pair 6 so that the first recording material 25 remains stopped at each detection unit 8a to 8f until the characteristic values ​​of the first recording material 25 (at least surface properties, stiffness, resistance, moisture content, basis weight, and paper thickness) are detected by the detection means 7a to 7f. The control unit 28 also causes each detection unit 8a to 8f to detect the characteristic values ​​of the first recording material 6 by the detection means 7a to 7f. The recording material information in the paper feed tray 3 consists of data from the recording material 25 detected by detection means (various paper information detection sensors, such as a size detection sensor) installed in the paper feed tray 3, and paper information input to the RAM 28B or storage unit 31 by the operation unit 23, which corresponds to the first characteristic detection result described later, and is recorded in the RAM 28B or storage unit 31 in a readable manner. The storage unit 31 is composed of storage means such as an HDD (hard disk drive) or SSD (solid state drive), and stores various programs and various setting data in a readable and writable manner.

[0023] As shown in Figures 1 to 3, the detection means 7a to 7f are installed in multiple detection units 8a to 8f provided along the transport path 5, and consist of sensors for detecting various characteristic values ​​of the recording material 25 (at least one of surface properties, stiffness, resistance, moisture content, basis weight, or paper thickness). Specifically, the detection means 7a to 7f consist of multiple types of sensors, including an optical sensor for detecting the surface properties of the recording material 25 (e.g., roughness, gloss), a mechanical stiffness detection sensor for detecting the stiffness of the recording material 25 (e.g., bending strength), a resistance sensor for detecting the resistance value of the recording material 25, a moisture detection sensor using near-infrared light for detecting the moisture content of the recording material 25, a basis weight detection sensor for detecting the basis weight of the recording material 25 (e.g., an optical sensor that measures basis weight from transmitted and reflected light irradiated onto the recording material 25), and a paper thickness detection sensor for detecting paper thickness (such as a rotary encoder that detects paper thickness from the displacement between the transport roller pair 6). The characteristic values ​​of the first recording material 25 detected by the respective detection means 7a to 7f of each of the detection units 8a to 8f are stored in the RAM 28B or storage unit 31 in a readable format as the first characteristic detection result (step S2). In this embodiment, the recording material determination device 1 is illustrated in which six detection units 8a to 8f are installed along the transport path 5, and different detection means 7a to 7f are installed in each detection unit 8a to 8f. However, the device is not limited to this configuration, and the number of detection units and detection means corresponding to the characteristic values ​​of the recording material 25 to be detected can be installed. Also, although Figure 1 shows a configuration in which each detection unit 8a to 8f detects one type of characteristic value, a configuration in which one detection unit detects multiple types of characteristic values ​​is also possible.

[0024] Next, as shown in Figures 3, 4, and 6, the control unit 28 of the recording material determination device 1 uses the first characteristic detection results stored in the RAM 28B or storage unit 31 (detection values ​​corresponding to each recording material characteristic value, and at least surface properties, stiffness, resistance, moisture content, basis weight, and paper thickness) to perform type determination of the recording material 25 based on a preset determination algorithm (step S3). As a result of this type determination, at least the type, basis weight, or paper profile is determined.

[0025] Next, as shown in Figures 3 and 4, the control unit 28 determines whether the result of type discrimination (at least one of type, basis weight, or paper profile) matches the paper information of the recording material 25 (as recording material information, at least one of type, basis weight, or paper profile corresponding to the result of type discrimination) that has been previously registered in the RAM 28B or storage unit 31 (step S4). The RAM 28B or storage unit 31 stores the information of the recording material 25 (type, basis weight, brand, paper profile, etc.) set by the user (input from the operation unit 23). This paper information of the recording material 25 stored in the RAM 28B or storage unit 31 is used when deciding which of the multiple paper feed trays 3 to use, and is also used when deciding the timing of image formation on the recording material 25.

[0026] Furthermore, the control unit 28 may omit step S3 (determination of paper type, basis weight, and paper profile) by determining whether the first characteristic detection result (at least one of surface properties, stiffness, or resistance) stored in the RAM 28B or storage unit 31 matches the information of the recording material 25 (at least one of surface properties, stiffness, or resistance) set in advance by the user, and instead determine whether the information of the recording material 25 set in the recording material determination device 1 matches the first characteristic detection result (step S4).

[0027] Next, as shown in Figures 3 and 4, when the control unit 28 determines that the recording material information set in the recording material determination device 1 (paper information registered in RAM 28B or storage unit 31) matches the type determination result (or the first characteristic detection result) (step S4; YES), it controls the operation of the transport roller pair 6 (transport unit 6A) so that the second recording material 25 can be transported without being stopped by the detection units 8a to 8f (step S5). As a result, the characteristic values ​​(at least one of basis weight, paper thickness, or moisture content) of the second recording material 25 are detected by the detection means 7a to 7f installed in the detection units 8a to 8f while it is being transported (step S5). The characteristic values ​​of the second recording material 25, which is transported without being stopped by each detection unit 8a to 8f, are then stored in the RAM 28B or storage unit 31 in a readable format as the second characteristic detection result.

[0028] Next, as shown in Figures 3 and 4, the control unit 28 compares the first characteristic detection result and the second specific detection result to determine whether the difference between the two is within the judgment threshold. If the difference between the two is within the judgment threshold (step S6; YES), it determines that the first recording material 25 and the second recording material 25 are identical (the first recording material 25 and the second recording material 25 have not changed) and proceeds to step S7. In Figure 4, the result detected when stopped (A) corresponds to at least one of the moisture content, basis weight, or paper thickness of the first characteristic detection result, and the result detected while transporting (B) corresponds to at least one of the moisture content, basis weight, or paper thickness of the second characteristic detection result.

[0029] Figure 7 is a diagram illustrating the judgment thresholds in the control unit 28. The judgment thresholds for moisture content and basis weight shown in Figure 7 are calculated based on the ratio of the detected value (second characteristic detection result) obtained by transporting the recording material 25 to the detected value (first characteristic detection result) obtained by stopping the recording material 25. The judgment threshold for paper thickness shown in Figure 7 is calculated as the difference between the detected value (first characteristic detection result) obtained by stopping the recording material 25 to the detected value (second characteristic detection result) obtained by transporting the recording material 25.

[0030] Next, as shown in Figures 3 and 4, in step S7, if the control unit 28 determines that the print job is not finished or that there is paper being fed from the same paper tray 3 (step S7; NO), it detects the characteristic value of the second recording material 25 (step S5), and the comparison between the first characteristic detection result and the second characteristic detection result continues (steps S6-S7). On the other hand, as shown in Figure 4, if a recording material detection sensor (not shown) installed in the paper tray 3 detects that the print job is finished or that there is no more paper being fed from the same paper tray 3, and a detection signal is input from the recording material detection sensor (step S7; YES), the control unit 28 stops the operation of the paper feed roller 4 and terminates this process.

[0031] Furthermore, in Figures 3 and 4, if the control unit 28 determines in step S1 that there is recording material information in the paper feed tray 3 (step S1; NO), it performs a type determination of the recording material 25 in the paper feed tray 3 and determines at least one of the following: the type of recording material 25, the basis weight, or the paper profile (step S3).

[0032] Furthermore, as shown in Figures 3 and 4, if the control unit 28 determines that the result of type determination in step S3 or the first characteristic detection result does not match the recording material information set in the recording material determination device 1 (step S4; NO), it displays on the display means 22 of the operation unit 23 and / or notifies the operator visually and / or audibly that the first recording material 25 (transfer material) does not match the recording material information set in the recording material determination device 1, and / or notifies the operator through a speaker (not shown) (step S8).

[0033] Furthermore, as shown in Figures 3 and 4, if the control unit 28 determines that the first characteristic detection result and the second characteristic detection result do not match (step S6; NO), it displays the mismatch between the first recording material 25 (transfer material) and the second recording material 25 (transfer material) on the display means 22 of the operation unit 23 and / or notifies the operator visually and / or audibly through a speaker (not shown) (step S8).

[0034] Figure 5 is a diagram comparing the case where the characteristic value is detected when the first recording material 25 is stopped at the detection units 8a to 8f (when transport variations are eliminated) and the case where the characteristic value is detected when the first recording material 25 is not stopped at the detection units 8a to 8f (when transport variations are present).

[0035] As shown in Figure 5, by stopping the first recording material 25 at the detection units 8a to 8f and detecting the characteristic values ​​of the first recording material 25 with the detection means 7a to 7f, it is determined that there is no deviation in the transport of the first recording material 25 (no deviation from the design reference value of 1.00), and when the characteristic values ​​of the second recording material 25 (the second and subsequent recording materials 25) are detected based on the characteristic values ​​of the first recording material 25, all characteristic values ​​are within the judgment threshold (±2%).

[0036] In contrast, when the first recording material 25 is transported and its characteristic value is detected, if there is a deviation in the transport of the first recording material 25, a deviation (a deviation from the design reference value of 1.00) will occur in the detection result of the characteristic value of the first recording material 25. If the characteristic value of the second recording material 25 (the second and subsequent recording materials 25) is detected based on the characteristic value of the first recording material 25 including this deviation (as the center of the judgment threshold), even if the detection results of all characteristic values ​​are within ±2% of the design reference value of 1.00, there is a possibility that it will be incorrectly judged as being outside the judgment threshold (within ±2%), resulting in an inaccurate measurement result of the characteristic value of the recording material 25, and an inaccurate judgment result by the control unit 28. Thus, the recording material judgment device 1 according to this embodiment stops the first recording material 25 with the detection units 8a to 8f and detects the characteristic value of the first recording material 25 in this stopped state, so that the judgment work by the control unit 28 is performed accurately.

[0037] As described above, with the recording material determination device 1 of this embodiment, the first recording material 25 is stopped at each detection unit 8a to 8f, while the second recording material 25 is passed through each detection unit 8a to 8f while being transported. Therefore, the matching or mismatch of the recording material 25 can be accurately determined without causing a decrease in productivity during image formation.

[0038] (Variation 1) Figure 8 is a flowchart of a modified example 1 of the recording material determination device 1 according to the first embodiment. Since steps S1 to S7 of the flowchart relating to this modified example are the same as those in the flowchart shown in Figure 4, redundant explanations will be omitted, and the differences from the flowchart shown in Figure 4 will be described in detail.

[0039] As shown in Figures 3 and 8, when the control unit 28 of the recording material determination device 1 determines that the first characteristic detection result and the second characteristic detection result do not match (step S6), the control unit 28 activates the transport path switching flap (purge means) 35 shown in Figure 1, and the transport path switching flap 35 guides the second recording material 25 from the normal transport path 5 to the purge transport path 36, and the second recording material 25 is discharged into the output tray (purge tray) 15 (purged (step S10)). In this modified example, when the control unit 28 of the recording material determination device 1 determines that the first characteristic detection result and the second characteristic detection result do not match (step S6), the control unit 28 stops the formation of a toner image on the intermediate transfer belt 11 by the image forming unit 10, and the transfer of the toner image to the second recording material 25 is prevented, making it possible to reuse the second recording material 25 discharged into the purge output tray 15.

[0040] Furthermore, as shown in Figure 3, the control unit 28 of the recording material determination device 1 of this modified example may, when purging the second recording material 25, display the mismatch between the first recording material 25 (transfer material) and the second recording material 25 (transfer material) on the display means 22 of the operation unit 23 and / or notify the user via a speaker (not shown), as described in the first embodiment.

[0041] According to the modified recording material determination device 1 described above, the same effects as the recording material determination device 1 according to the first embodiment can be obtained.

[0042] (Modification 2) Figure 9 is a flowchart of a modified example 2 of the recording material determination device 1 according to the first embodiment. Steps S1 to S4 and S7 to S8 of the flowchart relating to this modified example are the same as those in the flowchart shown in Figure 4, so redundant explanations will be omitted, and the differences from the flowchart shown in Figure 4 will be described in detail.

[0043] As shown in Figure 9, the control unit 28 of the recording material determination device 1 determines that the result of type determination matches the recording material information (paper information registered in RAM 28B or storage unit 31) set in RAM 28B or storage unit 31 (step S4), and determines that the detection result of the resistance value of the first recording material 25 is above a threshold (step S20), changes the gain of the gain changing circuit 33 (for example, an operational amplifier) ​​of the detection means for detecting moisture content (increases the gain), detects the moisture content of the first recording material 25 with the changed gain, and stores the characteristic value (moisture content) of the first recording material 25 in readable storage in RAM 28B or storage unit 31 as the first characteristic detection result (step S21). The control unit 28 also detects the characteristic value (moisture content) of the second recording material 25 using the detection means while maintaining the changed gain, and stores the detection result in readable storage in RAM 28B or storage unit 31 as the second characteristic detection result (step S5).

[0044] Furthermore, as shown in Figure 9, the control unit 28 compares the first characteristic detection result and the second specific detection result and determines whether the difference between the two is within the judgment threshold (step S6). In Figure 9, the result of detecting the first recording material 25 while it is stopped by the detection units 8a to 8f (Aa) is the first characteristic detection result, and the result of detecting the second recording material 25 while it is transported by the detection units 8a to 8f (B) is the second characteristic detection result. The first characteristic detection result and the second characteristic detection result compared by the recording material determination means 34 relate to moisture content, basis weight, and paper thickness.

[0045] According to this modified example, the recording material determination device 1 can achieve the same effects as the recording material determination device 1 according to the first embodiment.

[0046] Furthermore, according to the modified recording material determination device 1, the gain changing circuit 33 of the detection means for detecting the moisture content of the recording material 25 can accurately detect the moisture content by changing the gain of the gain changing circuit 33 when the resistance value of the first recording material 25 is greater than a threshold value.

[0047] <Second Embodiment> Figure 10 is a configuration diagram of an image forming apparatus 2 equipped with a recording material determination device 1 according to a second embodiment of the present invention.

[0048] As shown in Figure 10, the image forming apparatus 2 is composed of three units (37A, 37B, and 37C), from the first unit 37A to the third unit 37C. Sheet-shaped recording material 25 loaded on the paper feed tray (paper feed section) 3 is fed one sheet at a time to the transport path 5 by the paper feed roller 4, and the recording material 25 fed to the transport path 5 is transported along the transport path 5 by a transport section 6A consisting of multiple pairs of transport rollers 6. The transport path 5 has a horizontal transport path 38 that extends laterally from the first unit 37A to the third unit 37C, a first vertical transport path (first purge transport path) 40 that branches off from the horizontal transport path 38 in the second unit 37B and extends upward, and a second vertical transport path (second purge transport path) 41 that branches off from the horizontal transport path 38 in the third unit 37C and extends upward.

[0049] Furthermore, in the horizontal transport path 38 within the first unit 37A, detection units 8a to 8c and detection means 7a to 7c for detecting the moisture content, basis weight, and paper thickness of the first and second recording materials 25 are arranged side by side in the horizontal direction.

[0050] Furthermore, in the first vertical transport path 40 within the second unit 37B, detection units 8d to 8f and detection means 7d to 7f for detecting the surface properties, stiffness, and resistance of the first recording material 25 are arranged vertically. Within the second unit 37B, the transport direction of the recording material 25 can be switched between the horizontal transport path 38 and the first vertical transport path 40 by a first transport path switching flap (first purging means) 42 installed at the branching point of both transport paths 38 and 40.

[0051] Furthermore, within the third unit 37C, the horizontal transport path 38 and the second vertical transport path 41 are configured such that the transport direction of the recording material 25 can be switched by a second transport path switching flap (second purging means) 43 installed at the branching point of both transport paths 38 and 41.

[0052] In the third unit 37C, an image forming unit 44 consisting of a photoreceptor drum and the like, a transfer roller 45, a fixing unit 46, and a second transport path switching flap 43 are arranged sequentially from the upstream side to the downstream side in the transport direction of the horizontal transport path 38.

[0053] Furthermore, a first paper output tray (first purge tray) 47 is installed at the upper open end of the first vertical transport path 40 of the second unit 37B. Also, a second paper output tray (second purge tray) 48 is installed at the upper open end of the second vertical transport path 41 of the third unit 37C. In addition, a third paper output tray 50 is installed at the downstream open end of the horizontal transport path 38 of the third unit 37C in the recording material transport direction.

[0054] In such a recording material determination device 1, the first recording material 25 sent from the paper feed tray 3 to the transport path 5 is stopped at each detection unit 8a to 8c of the horizontal transport path 38 of the first unit 37A, where its characteristic values ​​are detected. After being guided to the first vertical transport path 40 by the first transport path switching flap 42, it is stopped at each detection unit 8d to 8f of the first vertical transport path 40, where its characteristic values ​​are detected, and then it is discharged into the first output tray 47.

[0055] Furthermore, in the recording material determination device 1, the second recording material 25 sent from the paper feed tray 3 to the transport path 5 is allowed to pass through the detection units 8a to 8c of the horizontal transport path 38 of the first unit 37A without being stopped, and characteristic values ​​are detected by the detection means 7a to 7c of each detection unit 8a to 8c.

[0056] Subsequently, as shown in Figures 3, 4, or 8, the recording material determination device 1 according to this embodiment compares the first characteristic detection result and the second characteristic detection result by the control unit 28. If it is determined that the result of the comparison is not within the determination threshold (step S6), the display means 22 of the operation unit 23 and / or the speaker notify that the first recording material 25 (transfer material) and the second recording material 25 (transfer material) are inconsistent. The second recording material 25 is then guided to the first longitudinal transport path 40 by the first transport path switching flap 42 and ejected (purged) into the first paper output tray 47. Alternatively, the second recording material 25 may be guided by the first transport path switching flap 42 to the horizontal transport path 38 side of the third unit 37C without being guided to the first vertical transport path 40 by the first transport path switching flap 42, and without a toner image being formed by the image forming unit 44 and the transfer roller 45, it may be guided by the second transport path switching flap 43 to the second vertical transport path 41 and discharged to the second output tray 48 via the second vertical transport path 41 (it may also be purged).

[0057] The recording material determination device 1 according to this embodiment, as described above, can obtain the same effects as the recording material determination device 1 according to the first embodiment.

[0058] (Other variations) The control unit 28 may set a smaller threshold for determining whether the first recording material 25 and the second recording material 25 have changed, as the thickness of the first recording material 25 increases.

[0059] Furthermore, the control unit 28 may correct the threshold value used to determine whether the first recording material 25 and the second recording material 25 have changed, based on the second characteristic detection result.

[0060] Furthermore, while the recording material determination device 1 is exemplified in the first and second embodiments as being applicable to an image forming apparatus 2 using an electrophotographic printing method, it is not limited to this and can also be applied to inkjet image forming apparatuses and other image forming apparatuses using other printing methods. [Explanation of Symbols]

[0061] 1. Recording material determination device 2 Image forming apparatus 5. Conveyor path 6A Conveyor Unit 8a~8f Detection section 10 Image forming unit 15 Purge Tray 22 Display means 25 Recording materials 28 Control Unit 33 Gain Change Circuit 44 Image forming unit 47, 48 Purge tray

Claims

1. A transport unit that transports recording material along a transport path, A detection unit is installed in the middle of the transport path to detect characteristic values ​​of the recording material while it is being transported. The system includes a control unit that controls the drive of the transport unit, stops the first recording material among the recording materials at the detection unit, and does not stop the second recording material, which is transported after the first recording material, at the detection unit. The control unit compares the first characteristic value detection result of the first recording material detected by the detection unit with the second characteristic value detection result of the second recording material detected by the detection unit, and determines whether the second characteristic value detection result falls within a predetermined threshold based on the first characteristic value detection result, thereby determining whether the second recording material has changed relative to the first recording material. The control unit sets the predetermined threshold for determining whether the first recording material and the second recording material have changed to a smaller value as the thickness of the first recording material increases. Recording material identification device.

2. The control unit causes the detection unit to detect at least one of the basis weight, paper thickness, and moisture content of the recording material as the characteristic value. The recording material determination device according to claim 1.

3. The control unit uses the first characteristic value detection result to determine whether the first recording material is a set recording material or not. The recording material determination device according to claim 1.

4. The control unit causes the detection unit to detect at least one of the surface properties, stiffness, and resistance value of the recording material as the characteristic value, and performs the determination based on at least one of the surface properties, stiffness, and resistance value. The recording material determination device according to claim 3.

5. The control unit determines at least one of the following: the type, basis weight, and paper profile of the first recording material and the set recording material. The recording material determination device according to claim 3.

6. When the control unit determines that the second recording material has changed relative to the first recording material, it causes the determination result to be displayed on the display means. The recording material determination device according to claim 1.

7. When the control unit determines that the second recording material has changed relative to the first recording material, it causes the transport unit to transport the second recording material to the purge tray. The recording material determination device according to claim 1.

8. If the control unit determines that the first recording material is not the designated recording material, it will display the determination result on the display means. The recording material determination device according to claim 3.

9. The detection unit includes a gain changing circuit, The control unit changes the gain of the gain changing circuit based on the first characteristic value detection result. The recording material determination device according to claim 2.

10. The control unit causes the detection unit to detect the resistance value of the first recording material, and if the resistance value among the first characteristic value detection results is greater than or equal to a threshold, it increases the gain of the gain changing circuit. The recording material determination device according to claim 9.

11. The control unit corrects the predetermined threshold value based on the second characteristic value detection result. The recording material determination device according to claim 1.

12. A transport step in which a transport unit transports recording material along a transport path, A detection step in which a detection unit installed in the middle of the transport path detects the characteristic values ​​of the recording material being transported, The system includes a control step that controls the drive of the transport unit, stops the first recording material among the recording materials at the detection unit, and does not stop the second recording material, which is transported after the first recording material, at the detection unit. The control step compares the first characteristic value detection result of the first recording material detected by the detection unit with the second characteristic value detection result of the second recording material detected by the detection unit, and determines whether the second characteristic value detection result falls within a predetermined threshold based on the first characteristic value detection result, thereby determining whether the second recording material has changed relative to the first recording material. The control step involves setting a predetermined threshold for determining whether the first recording material and the second recording material have changed to a smaller value as the thickness of the first recording material increases. Method for determining recording material.

13. A program that causes a computer to execute the recording material determination method described in claim 12.

14. A recording material determination device according to any one of claims 1 to 11, An image forming apparatus comprising an image forming unit that forms an image on the recording material.

Images