Paper characteristic detection apparatus, image forming system, and computer program product

Abstract

The invention provides a paper characteristic detection device, an image forming system and a computer program product, which can restrain reduction of detection precision of paper thickness of a recording medium. A sheet characteristic detection device includes a nip portion that nips a recording medium, a sheet thickness detection sensor, and a control portion. The paper thickness detection sensor detects displacement of the recording medium in the thickness direction in the nip. The control unit calculates the thickness of the recording medium on the basis of a detection value detected by the paper thickness detection sensor. In addition, the control unit corrects the detection value or the thickness detected by the paper thickness detection sensor according to the length of the recording medium in the width direction orthogonal to the conveyance direction or the length of the recording medium in the width direction of the portion in contact with the nip, and acquires the thickness of the recording medium.

Description

TECHNICAL FIELD

[0001] The present application relates to a paper property detection device, an image forming system, and a computer program product. BACKGROUND

[0002] An image forming system is provided with an image forming device that forms an image on a paper sheet, and a paper sheet supply device that supplies the paper sheet to the image forming device. In the image forming device, an image is formed on the paper sheet in accordance with output job information. In addition, the image forming system has a paper property detection device that detects the size and kind of the paper sheet before an image is formed on the paper sheet.

[0003] As such a paper property detection device in the related art, there is, for example, a device described in Patent Literature 1. In Patent Literature 1, a technology is described that is provided with a first roller and a second roller that sandwich a recording medium to convey, a roller shaft that rotatably supports the second roller, a shaft support portion, and a displacement detection portion. In addition, the shaft support portion movably supports the roller shaft in a thickness direction of the recording medium. Further, the displacement detection portion detects displacement in the thickness direction in the second roller.

[0004] PRIOR ART DOCUMENTS

[0005] Patent Literature 1: Japanese Patent Application Publication No. 2021-42049 SUMMARY

[0006] However, in the technology described in Patent Literature 1, it is known that in a case where the width of the recording medium and the length of the recording medium that contacts the sandwiching portion are shorter than the member that sandwiches the recording medium, even the same thickness of the recording medium, depending on the size of the recording medium, there are cases where a deviation occurs. Therefore, in the technology described in Patent Literature 1, there is a problem that the detection accuracy of the thickness of the recording medium decreases.

[0007] The present application aims to provide a paper property detection device, an image forming system, and a computer program product that can suppress a decrease in the detection accuracy of the thickness of the recording medium.

[0008] To solve the above problem and achieve the object of the present application, the paper property detection device of the present application is provided with a sandwiching portion that sandwiches a recording medium, a thickness detection sensor, and a control portion. The thickness detection sensor detects displacement in a thickness direction of the recording medium in the sandwiching portion. The control portion calculates the thickness of the recording medium based on a detection value detected by the thickness detection sensor. In addition, the control portion corrects the detection value or the thickness detected by the thickness detection sensor based on a length in a width direction of the recording medium that is orthogonal to the conveying direction or a length in the width direction of a portion of the recording medium that contacts the sandwiching portion, and acquires the thickness of the recording medium.

[0009] The image forming system of the present application includes: an image forming apparatus that forms an image on a recording medium; and a paper characteristic detection apparatus that is disposed on an upstream side of a conveying direction of the recording medium with respect to the image forming apparatus, and detects a characteristic of the recording medium. As the paper characteristic detection apparatus, the above-described paper characteristic detection apparatus is used.

[0010] In addition, the computer program product of the present application is a computer program product that causes the paper characteristic detection apparatus to execute the processes shown in (1) to (3) below.

[0011] (1) a process of detecting displacement in a thickness direction of the recording medium in a clamping portion that clamps the recording medium;

[0012] (2) a process of acquiring a length in a width direction of the recording medium that is orthogonal to the conveying direction or a length in the width direction of a portion of the recording medium that contacts the clamping portion; and

[0013] (3) a process of correcting a detected value or a thickness that is detected based on the length in the width direction of the recording medium or the length in the width direction of the portion of the recording medium that contacts the clamping portion, and acquiring a thickness of the recording medium.

[0014] According to the paper characteristic detection apparatus, the image forming system, and the computer program product described above, it is possible to suppress a decrease in detection accuracy of the thickness of the recording medium. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a schematic configuration diagram showing the overall configuration of an image forming system to which an embodiment example of the present application pertains.

[0016] Figure 2 is a block diagram showing the hardware configuration of a paper characteristic detection apparatus to which an embodiment example of the present application pertains.

[0017] Figure 3 is a schematic configuration diagram of a paper physical characteristic detection portion to which an embodiment example of the present application pertains.

[0018] Figure 4 is a cross-sectional view showing a clamping portion of a paper physical characteristic detection portion to which an embodiment example of the present application pertains.

[0019] Figure 5 is a diagram showing a schematic configuration of a paper physical characteristic detection portion to which an embodiment example of the present application pertains, and is a diagram showing a state in which a paper is clamped.

[0020] Figure 6 is a diagram showing a clamping portion of a paper physical characteristic detection portion to which an embodiment example of the present application pertains, and is a cross-sectional view showing a state in which a paper is clamped.

[0021] Figure 7 is a schematic configuration view showing a paper size detection section according to an embodiment of the present application.

[0022] Figure 8 is an explanatory view showing a difference in the amount of displacement of a driven roller shaft of a paper physical property detection section due to a difference in paper size (width direction length), Figure 8 A of is an example in which the paper width is shorter than the roller width, Figure 8 B of is an example in which the paper width is longer than the roller width.

[0023] Figure 9 is a table showing a change amount and a change ratio of a detection value of a paper thickness detection sensor and an actual paper thickness due to a difference in paper width (CD length) of a paper, and Figure 9 B of is a graph showing a detection value of a paper thickness detection sensor due to a difference in paper width of a paper.

[0024] Figure 10 is a graph showing an outline of a process for obtaining a correction coefficient.

[0025] Figure 11 is a flowchart showing an obtaining action of a correction coefficient in an image forming system according to an embodiment of the present application.

[0026] Figure 12 is a flowchart showing a calibration action in an image forming system according to an embodiment of the present application.

[0027] Figure 13 is a flowchart showing a paper thickness calculation action in an image forming system according to an embodiment of the present application.

[0028] Figure 14 is a flowchart showing one example of a paper thickness detection action in an image forming system according to an embodiment of the present application.

[0029] Figure 15 is an explanatory view showing a modification example of a paper thickness detection action in an image forming system according to an embodiment of the present application.

[0030] Figure 16 is a graph showing one example of a correction table in an image forming system according to an embodiment of the present application.

[0031] Figure 17 is an explanatory view showing a modification example of a paper thickness detection action in an image forming system according to an embodiment of the present application.

[0032] Figure 18is a view showing another example of the correction table in the image forming system according to the embodiment example of the present application.

[0033] Figure 19 is a flowchart showing a modification example of the paper thickness detection operation in the image forming system according to the embodiment example of the present application.

[0034] Figure 20 is a view showing another example of the correction table in the image forming system according to the embodiment example of the present application. DETAILED DESCRIPTION

[0035] Hereinafter, a manner for implementing the image forming system according to the present application will be described with reference to Figures 1-20 , to which like reference numerals are attached to common components in each drawing. In addition, the present application is not limited to the following manner.

[0036] 1. Embodiment Example

[0037] 1-1. Structure of Image Forming System

[0038] First, the overall structure of the image forming system according to the embodiment example of the present application (hereinafter referred to as "the present example") will be described. Figure 1 is a schematic configuration view of the image forming system 1 according to the present example.

[0039] As shown in Figure 1 , the image forming system 1 has a paper feeding unit 10 that feeds paper sheets S, an image forming apparatus 20, and a paper characteristic detection apparatus 30. The paper feeding unit 10, the image forming apparatus 20, and the paper characteristic detection apparatus 30 are connected to a network such as a LAN, and are connected to each other via the network. In addition, in the image forming system 1, from the upstream side of a paper sheet conveying path, the paper feeding unit 10, the paper characteristic detection apparatus 30, and the image forming apparatus 20 are arranged in this order and are connected in series.

[0040] The paper feeding unit 10 is arranged at the most upstream of the image forming system 1. It is configured to have a plurality of paper cassettes, and is capable of storing a large number of paper sheets. The paper feeding unit 10 feeds the paper sheets S stored in the paper cassettes to the paper characteristic detection apparatus 30 using a paper sheet conveying section.

[0041] In addition, as the image forming system 1, an example in which the paper feeding unit 10 is provided is described, but the present application is not limited thereto, and the image forming system 1 can not be provided with the paper feeding unit 10.

[0042] The paper characteristic detection device 30 detects characteristics of the paper sheet S conveyed, such as a paper type, a basis weight, a thickness, a surface property, a base, and a color of the paper sheet S. In addition, the paper characteristic detection device 30 has a paper size detection section 50 that detects a size of the paper sheet S, and a paper physical characteristic detection section 60 that detects a thickness of the paper sheet S. Further, the paper characteristic detection device 30 has a conveyance section 31 that conveys the paper sheet S, and a paper discharge section 32 that branches from the conveyance section 31 and discharges the paper sheet S to a paper discharge tray.

[0043] The paper size detection section 50 and the paper physical characteristic detection section 60 are disposed on the conveyance section 31. In addition, the paper size detection section 50 is disposed on an upstream side in a conveyance direction compared to the paper physical characteristic detection section 60. In addition, on a downstream side in the conveyance direction compared to the paper physical characteristic detection section 60 in the conveyance section 31, a branch section of the paper discharge section 32 is disposed. Further, the paper sheet S conveyed from the conveyance section 31 is conveyed to the image forming device 20.

[0044] The image forming device 20 forms an image on the paper sheet S supplied in accordance with the output job information and the image data. In addition, the image forming device 20 is, for example, a device that forms an image on the paper sheet S by an electrophotographic method. The image forming device 20 has a paper conveyance section 230, an operation display panel 240, an image forming section 270, a fixing section 280, and a reverse conveyance section 290.

[0045] The operation display panel 240 that is a report presentation section is disposed on an upper portion of a frame of the image forming device 20. The operation display panel 240 is a structure in which a display panel and a touch panel (operation section) are overlapped, and can realize an operation of a user and a display of information. The operation display panel 240 is, for example, a touch panel constituted of a display such as a liquid crystal display device (LCD) or an organic ELD (Electro Luminescence Display).

[0046] The operation display panel 240 is one example of a display section and an input section, and displays an instruction menu for a user, information related to acquired image data, and the like. Further, the operation display panel 240 has a plurality of keys, receives an input of various instructions, characters, numerical data, and the like performed by a key operation of the user, and outputs an input signal to a control section of the image forming device 20 and the paper characteristic detection device 30.

[0047] Further, in the present example, as the operation display panel 240, an example in which an input section and a display section are integrally constituted is described, but is not limited thereto, and the operation section and the display section can be separately constituted.

[0048] The paper sheet conveying section 230 conveys the paper sheet S supplied from the paper sheet supply unit 10 to the image forming section 270, the fixing section 280, the reverse conveying section 290, or the paper sheet discharge tray.

[0049] The image forming section 270 has, for example, a plurality of image forming units of colors (cyan, magenta, yellow, black, and the like), and is capable of forming a color toner image on a paper sheet. Downstream of the paper sheet conveying direction of the image forming section 270, the fixing section 280 that conveys a paper sheet on which a toner image is formed is arranged.

[0050] The fixing section 280 fixes a toner image transferred to a paper sheet S to the paper sheet S by applying pressure and heat to the paper sheet S. The paper sheet S on which the fixing process is performed by the fixing section 280 is conveyed to the reverse conveying section 290 or the paper sheet discharge tray by the paper sheet conveying section 230.

[0051] The reverse conveying section 290 is provided with a reversing section that reverses a paper sheet S. The paper sheet S that is reversed in the front and back or the top and bottom by the reversing section is conveyed to the upstream side of the image forming section 270 or the downstream side of the fixing section 280 via the reverse conveying section 290.

[0052] 1-2. Hardware configuration

[0053] Next, the hardware configuration of the paper sheet property detection device 30 will be described with reference to Figure 2

[0054] Figure 2 is a block diagram that shows the hardware configuration of the paper sheet property detection device 30.

[0055] As shown in Figure 2 , the paper sheet property detection device 30 has a control section 101, a paper sheet size detection section 50, a paper sheet physical property detection section 60, and a paper sheet conveying roller drive source 121 that drives the conveying section 31. The paper sheet size detection section 50 has a linear CIS (Contact Image Sensor) 151 that detects the size of a paper sheet S. The paper sheet physical property detection section 60 has a paper thickness detection sensor 161 and a paper leading end detection sensor 162. The paper thickness detection sensor 161 detects the thickness of a paper sheet S. The paper leading end detection sensor 162 detects the upper end, i.e., the leading end, of the conveying direction of a paper sheet S that is conveyed to the paper sheet physical property detection section 60. In addition, the control section 101 is connected to the operation display panel of the image forming device 20 via a serial communication (UART) circuit 106.

[0056] ​The control section 101 has, for example, a CPU (Central Processing Unit) 102, an EEPROM (Electrically Erasable Programmable Read-Only Memory) 103 which is one example of a display storage section, an LED drive circuit 104, a motor drive circuit 105, and a serial communication circuit 106. The EEPROM 103, the LED drive circuit 104, the motor drive circuit 105, and the serial communication circuit 106 are connected to the CPU 102.

[0057] A program or the like which is executed by the CPU 102 is stored in the EEPROM 103, and is used as a work area of the CPU 102. In addition, in the EEPROM 103, a correction coefficient K, a correction table which are used when the thickness of the paper sheet S is calculated are stored.

[0058] The LED drive circuit 104 is connected to the paper size detection section 50. Also, the LED drive circuit 104 outputs a drive signal to an LED which is one example of a display light source provided to the paper size detection section 50.

[0059] The motor drive circuit 105 is connected to the paper conveying roller drive source 121. The motor drive circuit 105 controls the drive of the paper conveying roller drive source 121 in accordance with a control signal from the CPU 102. Thus, the conveying of the paper sheet S which is fed in the paper property detection device 30 is controlled.

[0060] The CPU 102 has a thickness calculation section 111, a paper size calculation section 112, a physical property detection control section 113, and a paper size detection control section 114. The thickness calculation section 111 is connected to the thickness detection sensor 161 and the paper leading end detection sensor 162. Also, the thickness calculation section 111 receives a pulse signal from the thickness detection sensor 161 and a paper detection signal from the paper leading end detection sensor 162. In addition, the thickness calculation section 111 calculates the thickness of the paper sheet S in accordance with these signals, the size information of the paper sheet S, the correction coefficient K, the correction table which are stored in the EEPROM 103.

[0061] Furthermore, the paper thickness calculation unit 111 is connected to the physical property detection and control unit 113. The physical property detection and control unit 113 controls the paper physical property detection unit 60 via the paper thickness calculation unit 111. Additionally, the physical property detection and control unit 113 acquires the paper size information input by the user to the operation display panel 240 via the serial communication circuit 106. If the user does not input paper size information to the operation display panel 240, the physical property detection and control unit 113 acquires the paper size information calculated by the paper size calculation unit 112 via the paper size detection and control unit 114 (described later).

[0062] The paper size calculation unit 112 calculates the size of the paper S based on the output signal from the CIS 151 provided in the paper size detection unit 50. Furthermore, the paper size calculation unit 112 is connected to the paper size detection control unit 114. The paper size detection control unit 114 controls the paper size detection unit 50 via the paper size calculation unit 112. Additionally, the paper size detection control unit 114 sends the paper size information calculated by the paper size calculation unit 112 to the physical property detection control unit 113.

[0063] 1-3. Structural Example of Paper Physical Property Testing Unit

[0064] Next, refer to Figures 3-6 This describes the structure of the paper physical properties detection unit 60.

[0065] Figure 3 as well as Figure 5 This is a schematic structural diagram showing the paper physical property detection unit 60. Figure 4 as well as Figure 6 This is a cross-sectional view showing the paper physical property detection unit 60. Furthermore, Figure 3 as well as Figure 4 This shows the state without paper (S). Figure 5 as well as Figure 6 The state of having paper S is shown.

[0066] like Figure 3 As shown, the paper physical property detection unit 60 includes a drive roller 61, a driven roller 62, a first roller 63 indicating the first clamping part, a second roller 64 indicating the second clamping part, a force application member 65, a support part 67, and a paper thickness detection sensor 161.

[0067] The drive roller shaft 61 is connected to the paper conveyor roller drive source 121. The drive roller shaft 61 is rotated by the paper conveyor roller drive source 121. The drive roller shaft 61 is orthogonal to the conveying direction and is arranged parallel to the width direction of the paper S.

[0068] In this example, the drive roller shaft 61 is provided with two first rollers 63. The two first rollers 63 are arranged at intervals along the axial direction of the drive roller shaft 61. Furthermore, the two first rollers 63 rotate as the drive roller shaft 61 rotates.

[0069] The driven roller shaft 62 is arranged axially parallel to the drive roller shaft 61. The driven roller shaft 62 is also arranged opposite the drive roller shaft 61. The driven roller shaft 62 is rotatably supported. Furthermore, the driven roller shaft 62 is supported in a manner that allows it to move towards and away from the drive roller shaft 61. While the drive roller shaft 61 is rotatably supported, its movement towards and away from the driven roller shaft 62 is restricted.

[0070] The driven roller shaft 62 is provided with two second rollers 64. The two second rollers 64 are arranged at intervals in the direction of the driven roller shaft 62. The two second rollers 64 are opposite to the first roller 63 provided on the drive roller shaft 61. Furthermore, as... Figure 5 as well as Figure 6 As shown, the first roller 63 and the second roller 64 hold the paper S.

[0071] Furthermore, force-applying members 65 are respectively disposed at both ends of the driven roller shaft 62 along its axial direction. One end of the force-applying member 65 abuts against the driven roller shaft 62. The other end of the force-applying member 65 is disposed on the support portion 67 opposite to the driven roller shaft 62. Moreover, the force-applying member 65 applies force to the driven roller shaft 62 toward the drive roller shaft 61.

[0072] By applying force to the driven roller shaft 62 toward the drive roller shaft 61, thus... Figure 4 As shown, the second roller 64, supported on the driven roller shaft 62, applies force toward the first roller 63. Furthermore, when the first roller 63 is rotated, the second roller 64 also rotates together with the first roller 63. Additionally, by rotating both the first roller 63 and the second roller 64, as shown... Figure 5 as well as Figure 6 As shown, the first roller 63 and the second roller 64 transport the paper S held in the grip.

[0073] As the force-applying component 65, a compression disc spring may be used, for example. However, the force-applying component 65 is not limited to a compression disc spring, but may include various other elastic components such as leaf springs and rubber.

[0074] Additionally, the lever of the paper thickness detection sensor 161 abuts between the two second rollers 64 in the driven roller shaft 62. The paper thickness detection sensor 161 is disposed on the side of the driven roller shaft 62 opposite to the drive roller shaft 61.

[0075] like Figure 5 as well as Figure 6As shown, when the paper S enters between the first roller 63 and the second roller 64, the driven roller shaft 62 overcomes the force applied by the force-applying member 65 and displaces away from the drive roller shaft 61. Additionally, the lever of the paper thickness detection sensor 161, which abuts against the driven roller shaft 62, also rotates away from the drive roller shaft 61. Furthermore, the paper thickness detection sensor 161 detects the paper thickness of the paper S based on the rotation angle of the lever. The paper thickness calculation unit 111 calculates the paper thickness of the paper S based on the detection values ​​of the paper thickness detection sensor 161 when there is no paper S between the first roller 63 and the second roller 64, and when there is paper S between the first roller 63 and the second roller 64.

[0076] In addition, such as Figure 6 As shown, a paper tip detection sensor 162 is disposed downstream of the first roller 63 and the second roller 64 in the conveying direction. The paper tip detection sensor 162 detects the tip of the paper S. Furthermore, the control unit 101 determines whether there is paper S between the first roller 63 and the second roller 64 based on the paper detection information from the paper tip detection sensor 162.

[0077] Furthermore, the first roller 63 may be made of resin, for example. And the second roller 64 may be made of elastic rubber, for example. Moreover, the materials of the first roller 63 and the second roller 64 are not limited to the materials described above. For example, the first roller 63 may be made of metal or rubber, and the second roller 64 may be made of metal or resin.

[0078] Furthermore, although examples of rollers as rotating bodies being used as the first clamping part and the second clamping part have been described, this is not a limitation; flat or roughly semi-circular guide plates may also be used.

[0079] 1-4. Structural Example of Paper Size Inspection Unit

[0080] Next, refer to Figure 7 This explains the structure of the paper size detection unit 50.

[0081] Figure 7 This is a schematic structural diagram showing the paper size detection unit 50.

[0082] like Figure 7 As shown, the paper size detection unit 50 has a CIS151 that is longer than the width T of the paper S being transported. Furthermore, the CIS151 is a sensor that integrates multiple light-receiving units, multiple LEDs representing the light source, and a lens for optical imaging.

[0083] Multiple LEDs illuminate the paper S. Multiple light-receiving units receive the light reflected from the paper S. While conveying the paper S, the light-receiving units of the CIS151 detect the boundary lines of the front and rear ends of the paper S, as well as the boundary lines of both ends in the width direction of the paper S. Furthermore, the paper size calculation unit 112 calculates the length T in the width direction of the paper S and the length L in the direction parallel to the conveying direction of the paper S based on the output signal from the CIS.

[0084] 2. Differences in the displacement of the driven roller shaft due to variations in paper size.

[0085] Next, refer to Figures 8-9 This explains the difference in displacement of the driven roller 62 of the paper physical property detection unit 60 caused by the difference in the length of the paper in the width direction (hereinafter referred to as the paper width).

[0086] Figure 8 A and Figure 8 Figure B is an explanatory diagram showing the difference in displacement of the driven roller 62 of the paper physical property detection unit 60 due to differences in paper size (length in the width direction). Furthermore, in Figure 8 A and Figure 8 In section B, an example is given where the axial length (hereinafter referred to as the roll width) of one end of the two first rolls 63 and the two second rolls 64 is 130 mm.

[0087] in addition, Figure 9 Table A shows the changes in the paper thickness detected by the paper thickness sensor 161 and the actual paper thickness, as well as the percentage changes, due to variations in the paper width (CD length). Furthermore, Figure 9 B is a graph showing the detection values ​​of the paper thickness detection sensor 161 due to the difference in paper width. Figure 9 The horizontal axis of B indicates the paper width. Figure 9 The vertical axis of A represents the detected value. Figure 9 A and Figure 9 In B, the basis weight is shown to be 68 g / m³. 2 Paper and 128g / m 2 Data on the paper.

[0088] like Figure 8 As shown in B, when the width of the tested paper S2 is sufficiently longer than the roll width, i.e., the paper width is 130 mm or more, the paper S2 makes full-surface contact with both the first roll 63 and the second roll 64. Therefore, no collapse occurs in the second roll 64. The result is as follows: Figure 9 A and Figure 9As shown in B, the detected value of the paper thickness sensor 161 is no different from the actual paper thickness, and the amount and percentage of change are approximately 0. That is, when the width of the paper S2 is sufficiently longer than the width of the roll, the paper thickness of the paper S2 can be detected with high precision.

[0089] In contrast, when the width of the paper S1 being tested is shorter than the width of the roller, the paper S1 only contacts a portion of the first roller 63 and the second roller 64. Furthermore, pressure is applied locally to the portion of the second roller 64 that contacts the paper S1, causing the second roller 64 to partially collapse. Therefore, the displacement of the driven roller shaft 62 supporting the second roller 64 is reduced.

[0090] Therefore, as Figure 9 A and Figure 9 As shown in Figure B, the difference between the detected value of the paper thickness sensor 161 and the actual paper thickness increases, resulting in a decrease in the detection accuracy of the paper thickness of paper S1. The same result can be observed when using papers with different basis weights.

[0091] Furthermore, the shorter the paper width, the greater the amount of collapse on the second roll 64. Therefore, as... Figure 9 A and Figure 9 As shown in B, it can be seen that the shorter the paper width, the lower the detection accuracy proportionally.

[0092] In the control unit 101 of the image forming system 1 in this example, the detection value of the paper physical property detection unit 60 is corrected and controlled according to the paper width to improve the detection accuracy of paper thickness.

[0093] 3. Actions

[0094] 3-1. Obtaining the correction coefficient

[0095] First, refer to Figures 10-13 This indicates the action taken to obtain the correction coefficient K used for correction control.

[0096] Figure 10 This is a graph showing a summary of the methods used to obtain the correction coefficients. Figure 10 The horizontal axis indicates the general dimensions of the paper. Figure 10 The vertical axis shows the paper thickness measurement value. Figure 11 This is a flowchart illustrating the process of obtaining the correction coefficient K. Figure 12 This is a flowchart illustrating the calibration process. Figure 13 This is a flowchart illustrating the paper thickness calculation process.

[0097] exist Figures 10-13In the example shown, using general paper sizes, an example is given of feeding A6 size (105mm wide), which is shorter than the roll width, and A4 size (210mm wide), which is longer than the roll width, in the paper characteristic detection device 30 to obtain a correction coefficient K. Furthermore, the following actions are performed during the adjustment operation in the production process of the image forming system 1.

[0098] First, such as Figure 11 As shown, the control unit 101 issues the following instructions to the operator via the operation display panel 240: It instructs the operator to place A4-sized paper into the first paper tray of the paper feeding unit 10, and instructs the operator to place A6-sized paper into the second paper tray of the paper feeding unit 10. Additionally, the control unit 101 sets the width x1 (105mm) of the A6-sized paper to the EEPROM 103, and sets the width x2 (210mm) of the A4-sized paper to the EEPROM 103 (step S11).

[0099] Then, the operator places one A4-sized sheet of paper into the first paper feed tray and one A6-sized sheet of paper into the second paper feed tray. Next, the control unit 101 determines whether the paper setting is complete (step S12). If the control unit 101 determines that the paper setting is complete during the processing of step S12 (yes determination in step S12), it determines whether there is paper in the first paper feed tray (step S13).

[0100] In step S13, if the control unit 101 determines that there is paper in the first paper feed box (yes determination in step S13), it performs the calculation of the paper thickness of A4 size paper (step S14).

[0101] In step S14, calibration is first performed, and then the paper is fed into the paper characteristic detection device 30 to perform paper detection using the paper physical characteristic detection unit 60. Then, the paper thickness is calculated using the paper thickness calculation unit 111.

[0102] Here, refer to Figure 12 This indicates the calibration procedure.

[0103] like Figure 12 As shown, the paper thickness calculation unit 111 waits for an initialization instruction from the physical property detection and control unit 113 (step S31). When the initialization instruction is given, the paper thickness calculation unit 111 clears all the detection values ​​and calculation values ​​from the paper thickness detection sensor 161 to zero (step S32).

[0104] Next, the paper thickness calculation unit 111 waits for a detection start instruction from the physical property detection control unit 113 (step S33). Then, the paper thickness calculation unit 111 waits for a measurement start instruction from the control unit 101 (step S34). Next, the paper thickness calculation unit 111 obtains the sensor count value (detection value) from the paper thickness detection sensor 161 (step S35). Then, the paper thickness calculation unit 111 records the detection value (no paper value) of the state in which the paper is not feeding in the paper physical property detection unit 60 to an example of the storage unit EEPROM 103 (step S36). Thus, the calibration operation is completed.

[0105] Next, refer to Figure 13 This explains the paper detection operation performed by the paper physical property detection unit 60 and the paper thickness calculation operation performed by the paper thickness calculation unit 111.

[0106] like Figure 13 As shown, the paper thickness calculation unit 111 waits for a detection start instruction from the physical property detection control unit 113 (step S41). Then, the paper thickness calculation unit 111 waits for a measurement start instruction from the control unit 101 (step S42).

[0107] Next, the paper thickness calculation unit 111 determines whether the paper front detection sensor 162 has detected paper, that is, whether there is paper in the paper physical property detection unit 60 (step S43). If it is determined in step S43 that there is paper in the paper physical property detection unit 60 (yes determination in step S43), the paper thickness calculation unit 111 obtains the sensor count value (detection value) from the paper thickness detection sensor 161 (step S44). Then, the paper thickness calculation unit 111 records the detection value (paper presence value) of the paper feeding state in the paper physical property detection unit 60 into an example of the EEPROM 103 representing the storage unit (step S45).

[0108] Next, the paper thickness calculation unit 111 calculates the paper thickness measurement value (step S46). In step S46, the paper thickness calculation unit 111 calculates the paper thickness measurement value by subtracting the paperless value obtained during the calibration operation from the paper-containing value obtained in step S45. Then, the paper thickness calculation unit 111 records the calculated paper thickness measurement value into the EEPROM 103 (step S47). Thus, the paper detection operation performed by the paper physical property detection unit 60 and the paper thickness calculation operation performed by the paper thickness calculation unit 111 are completed.

[0109] Return to Figure 11The paper thickness calculation unit 111 stores the paper thickness measurement value calculated in step S14 as the paper thickness detection value Y2 of A4 size paper in EEPROM 103 (step S15). Next, the control unit 101 determines whether the paper whose paper thickness has been measured should be discharged to the paper discharge tray of the image forming apparatus 20 or the paper characteristic detection device 30 (step S16).

[0110] If, in step S16, it is determined that paper has been discharged into the paper tray (yes determination in step S16), it is determined whether there is paper in the second paper feed box (step S17). If, in step S17, the control unit 101 determines that there is paper in the second paper feed box (yes determination in step S17), it performs a calculation of the thickness of A6-sized paper (step S18). Furthermore, the calculation operation in step S18 is the same as the calculation operation in step S14, so its explanation is omitted.

[0111] The paper thickness calculation unit 111 stores the paper thickness measurement value calculated in step S18 as the paper thickness detection value Y1 for A6 size paper in EEPROM 103 (step S19). As a result, the following can be obtained: Figure 10 The data shown is linear.

[0112] Next, the control unit 101 determines whether the paper for which the paper thickness measurement has been performed has been discharged into the paper discharge tray of the image forming apparatus 20 or the paper characteristic detection device 30 (step S20). If it is determined in step S20 that the paper has been discharged into the paper discharge tray ("yes" determination in step S20), the paper thickness calculation unit 111 calculates the correction coefficient K (step S21).

[0113] In addition, it is possible to obtain from Figure 10 The slope of the linear data shown is used to obtain the correction coefficient K. That is, when the paper width of A6 size paper is set as X1, the paper width of A4 size paper is set as X2, the detection value of A6 size paper is set as Y1, and the detection value of A4 size paper is set as Y2, the correction coefficient K can be calculated according to the following mathematical formula 1.

[0114] [Mathematical Expression 1] K = (Y2 - Y1) / (X2 - X2)

[0115] Next, the control unit 101 determines whether the calculated correction coefficient K > 0 (step S22). If the control unit 101 determines that the correction coefficient K > 0 during the processing of step S22 (yes determination in step S22), the control unit 101 stores the calculated correction coefficient K in EEPROM 103 (step S23). Thus, the calculation of the correction coefficient K is completed.

[0116] Furthermore, if the control unit 101 determines in step S22 that the correction coefficient K is 0 or below (No determination in step S22), the control unit 101 determines that the adjustment operation has failed (step S24). Then, the control unit 101 returns to the process of step S11 and performs the operation of obtaining the correction coefficient K again. As a result, the correction coefficient K can be reliably obtained in the adjustment operation in the production process of the image forming system 1.

[0117] 3-2. An example of paper thickness detection operation

[0118] Next, refer to Figure 14 This is an example illustrating a paper thickness detection action that uses the aforementioned correction factor K.

[0119] Figure 14 This is a flowchart illustrating the paper thickness detection process.

[0120] like Figure 14 As shown, the control unit 101 first determines whether the operation of the image forming system 1 has started (step S51). If it is determined in step S51 that the operation has started, the paper thickness calculation operation of the paper being transported to the paper characteristic detection device 30 is performed (step S52). In step S52, calibration is first performed, and then the paper is fed in the paper characteristic detection device 30, and the paper detection operation is performed by the paper physical characteristic detection unit 60. Then, the paper thickness calculation operation is performed by the paper thickness calculation unit 111. Furthermore, the process of step S52 is the same as that of steps S14 and S18 described above, so its description is omitted.

[0121] Next, the control unit 101 stores the paper thickness measurement value calculated in step S52 as Z1 in the EEPROM 103 (step S53). Next, the control unit 101 determines whether there is information related to the paper width and paper size of the measured paper from the operation display panel 240 (step S54).

[0122] If, during the processing of step S54, it is determined that paper width dimension information is available from the operation display panel 240 (a "yes" determination is made in step S54), the control unit 101 obtains the paper width dimension information from the operation display panel 240 (step S55). Conversely, if, during the processing of step S54, it is determined that paper width dimension information is not available from the operation display panel 240 (a "no" determination is made in step S54), the control unit 101 obtains the paper width dimension information from the paper size detection unit 50 (step S56).

[0123] After obtaining the paper width information, the control unit stores the paper width information as paper width X3 in EEPROM 103 (step S57). Next, it determines whether the stored paper width X3 is greater than or equal to the roll width (e.g., 130 mm) (step S58). If the control unit 101 determines in step S58 that the paper width X3 is greater than or equal to the roll width (e.g., 130 mm), the paper thickness calculation unit 111 does not perform the calculation for correction, but instead sets the measured detection value Z1 calculated in step S52 as the corrected detection value Z2 (step S59). Then, the control unit 101 outputs the corrected detection value Z2 as the paper thickness.

[0124] Furthermore, if the control unit 101 determines in step S58 that the paper width X3 is less than the roll width (e.g., 130 mm), the control unit 101 reads the correction coefficient K from the EEPROM 103 (step S60). Next, the paper thickness calculation unit 111 uses the correction coefficient K to correct the measured detection value Z1 calculated in step S52, and calculates the corrected detection value Z2 (step S61). For example, if the roll width is 130 mm, the corrected detection value Z2 is calculated according to the following mathematical formula 2.

[0125] [Mathematical Expression 2] Z2=(130-X3)×K+Z1

[0126] Then, the control unit 101 outputs the corrected detection value Z2 as the paper thickness. Thus, the paper thickness detection operation performed by the image forming system 1 is completed.

[0127] Thus, according to the image forming system 1 of this example, when the paper width is less than the roll width, paper thickness correction is performed in steps S60 and S61. Therefore, even when the paper width is less than the roll width and the detection accuracy is reduced due to the second roll 64 being compressed, paper thickness can still be accurately detected. As a result, the reduction in the detection accuracy of the paper thickness value can be suppressed.

[0128] 3-3. Variations in paper thickness detection procedures

[0129] Next, refer to Figures 15-20 This illustrates a variation of the paper thickness detection procedure.

[0130] Figure 15 as well as Figure 17 This is an explanatory diagram showing a variation of the paper thickness detection operation. Figure 16 as well as Figure 18 The calibration table shown is used in a variation of the paper thickness detection operation.

[0131] like Figure 15As shown, in the paper physical property detection unit 60 described above, a paper thickness detection sensor 161 is arranged between the two second rollers 64. Here, the interval between the two second rollers 64 is set to, for example, 30 mm. Therefore, the actual contact length (hereinafter referred to as the contact width) x 4 between the second roller 64 and the paper S2 is the value obtained by subtracting the interval between the two second rollers 64 from the paper width.

[0132] Furthermore, in the paper thickness detection operation involved in the modified example, a pre-made... Figure 16 The correction table shown is then stored in EEPROM 103. (This is part of the process of creating...) Figure 16 When using the calibration table shown, the contact width X4 is calculated by subtracting two intervals of the second roller 64 from the paper width X3. Furthermore, calibration values ​​H corresponding to multiple paper widths X3 and contact widths X4 are measured and used as... Figure 16 The correction table shown is stored in EEPROM 103.

[0133] in addition, Figure 17 This is a diagram showing a modified example of the paper physical property detection section. Figure 17 In the paper physical property detection unit 60B shown, the paper thickness detection sensor 161 is disposed at one end of the driven roller shaft 62 along its axial direction. Therefore, the second roller 64 is not divided into multiple parts. Figure 17 In the paper physical property detection unit 60B shown, the actual contact length (hereinafter referred to as contact width) X4 between the second roller 64 and the paper S2 is consistent with the paper width X3.

[0134] exist Figure 17 The paper physical property detection unit 60B shown also has... Figure 16 Similarly, the calibration table shown can be created by measuring the calibration values ​​H corresponding to multiple paper widths X3 and contact widths X4. Figure 18 The correction table is shown. And, Figure 18 The calibration table shown is stored in EEPROM 103.

[0135] Next, refer to Figure 19 This illustrates a variation of the paper thickness detection procedure.

[0136] Figure 19 This is a flowchart illustrating a variation of the paper thickness detection operation.

[0137] like Figure 19 As shown, the processing of steps S71 to S77 is similar to... Figure 14The processes in steps S51 to S57 are the same, so their descriptions are omitted. When the paper width dimension information storage process in step S77 ends, the control unit 101 calculates the paper contact width X4 based on the paper width X3 (step S78). In the process of step S78, in Figure 15 In the case of the paper physical property detection unit 60 shown, the contact width X4 (X4 = X3 - 30) is obtained by subtracting the interval of two second rollers 64 (e.g., 30 mm) from the paper width X3. Furthermore, in Figure 17 In the case of the paper physical property detection unit 60B shown, the paper width X3 becomes the contact width X4 (X4 = X3). That is, regarding the contact width, the contact width with the actual paper is obtained based on information related to the configuration of the roller itself (the width of the roller itself, its position on the conveying path of the roller itself, including the aforementioned interval, etc.).

[0138] Next, the control unit 101 reads the correction amount H corresponding to the calculated contact width X4 from the correction table pre-stored in the EEPROM 103 (step S79). Then, the paper thickness calculation unit 111 uses the read correction amount H to correct the measured detection value Z1 calculated in step S72, and calculates the corrected detection value Z2 (step S80). In the processing of step S80, the corrected detection value Z2 is calculated according to the following mathematical formula 3.

[0139] [Mathematical Formula 3] Z2 = Z1 + H

[0140] Furthermore, the control unit 101 outputs the corrected detection value Z2 as the paper thickness. Thus, the paper thickness detection operation performed by the image forming system 1 is completed.

[0141] Even in paper thickness detection operations using such a calibration table, when the paper contact width is less than the roll width, the detection value can be corrected according to the calibration value, thus suppressing the decrease in the detection accuracy of the paper thickness.

[0142] In addition, the amount of collapse of the second roller 64 will vary depending on the material of the second roller 64. Figure 20 Is with Figure 16 The calibration table shown is for the second roller 64 made of different materials. Furthermore, in the event that the second roller 64 is replaced with a roller of a different material during maintenance or other operations, the operator will retrieve the calibration table stored in EEPROM 103 from... Figure 16 The correction table shown has been changed to Figure 20 The calibration table shown is used to obtain the optimal calibration value by using a calibration table suitable for the material of the second roll 64 during paper thickness detection, thereby improving the detection accuracy of the paper thickness.

[0143] The calibration table stored in EEPROM 103 is appropriately modified according to the material of the roller and the structure of the paper physical property detection unit. In addition, multiple calibration tables can be stored in EEPROM 103 according to the material of the roller and the structure of the paper physical property detection unit, and the best calibration table can be selected from multiple calibration tables when performing paper thickness detection.

[0144] The above description of the embodiments, including their effects, has been provided. However, the invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the invention as described in the claims.

[0145] In the above-described embodiments, an example of the operation being performed by the control unit 101 of the paper characteristic detection device 30 was presented, but the implementation is not limited to this. For example, it may also be performed by a control unit that controls the image forming apparatus 20 or a control unit that controls the image forming system 1 as a whole. Furthermore, the paper characteristic detection device 30 may be installed within the image forming apparatus 20.

[0146] Furthermore, although paper has been used as an example of a recording medium, it is not limited to this. Various other media such as film and cloth can be used as recording media.

[0147] Furthermore, the aforementioned components, functions, and processing units can be partially or entirely implemented in hardware, such as through integrated circuit design. Alternatively, the aforementioned components and functions can be implemented in software by a processor interpreting and executing programs that perform each function. The programs, tables, files, and other information implementing these functions can be stored in recording devices such as memory, hard disks, SSDs (Solid State Drives), or recording media such as IC cards, SD cards, and DVDs.

[0148] Furthermore, the terms “parallel” and “orthogonal” are used in this specification, but they do not only mean strictly “parallel” and “orthogonal”, but also include “parallel” and “orthogonal”, and can also refer to a state of “approximately parallel” and “approximately orthogonal” within the range where they can perform their functions.

[0149] [Explanation of Symbols]

[0150] 1: Image forming system; 10: Paper feeding unit; 20: Image forming apparatus; 30: Paper characteristic detection device; 31: Conveying section; 32: Paper discharge section; 50: Paper size detection section; 60, 60B: Paper physical characteristic detection section; 61: Drive roller; 62: Driven roller; 63: First roller (first clamping section); 64: Second roller (second clamping section); 65: Force application component; 67: Support section; 101: Control section; 102: CPU; 103: EEPROM (storage section); 10 4: LED driver circuit; 105: Motor drive circuit; 106: Serial communication circuit; 111: Paper thickness calculation unit; 112: Paper size calculation unit; 113: Physical property detection and control unit; 114: Paper size detection and control unit; 121: Paper conveying roller drive source; 161: Paper thickness detection sensor; 162: Paper front end detection sensor; 230: Paper conveying unit; 240: Operation display panel (input unit); 270: Image forming unit; 280: Fixing unit; 290: Flip conveying unit.

Claims

1. A paper characteristic detection device, comprising: Clamping section, for clamping the recording medium; A paper thickness detection sensor detects the displacement of the recording medium in the thickness direction within the clamping portion; and The control unit calculates the thickness of the recording medium based on the detection value detected by the paper thickness detection sensor. The control unit corrects the detection value or the thickness detected by the paper thickness detection sensor based on the length of the width direction of the recording medium orthogonal to the conveying direction or the length of the width direction of the portion of the recording medium in contact with the clamping part, and obtains the thickness of the recording medium.

2. The paper characteristic detection device according to claim 1, wherein, The clamping part is a roller.

3. The paper characteristic detection device according to claim 2, wherein, The clamping part has: Roller 1; and The second roller is arranged opposite to the first roller. The paper characteristic detection device includes a roller shaft that can rotatably support the second roller. The paper thickness detection sensor detects the displacement in the thickness direction of the roller.

4. The paper characteristic detection device according to claim 1, wherein, The clamping part is formed of a flexible component.

5. The paper characteristic detection device according to claim 3, wherein, At least one of the first roller and the second roller is formed of a resilient component.

6. The paper characteristic detection device according to claim 1, wherein, The paper characteristic detection device includes an input section for inputting the size of the recording medium. The control unit obtains the length of the recording medium in the width direction from the size information input to the input unit.

7. The paper characteristic detection device according to claim 1, wherein, The paper characteristic detection device includes a dimension detection unit that detects the length of the recording medium in the width direction. The control unit obtains the length of the recording medium in the width direction from the information detected by the size detection unit.

8. The paper characteristic detection device according to claim 7, wherein, The size detection unit is a linear sensor disposed along the paper conveying path.

9. The paper characteristic detection device according to claim 1, wherein, The length of the portion of the recording medium that contacts the clamping part is obtained based on information related to the configuration of the clamping part and the length of the recording medium in the width direction orthogonal to the conveying direction.

10. The paper characteristic detection device according to claim 1, wherein, If the length of the recording medium in the width direction is greater than the length of the clamping part in the width direction, the control unit will not perform the correction of the detection value or the thickness.

11. The paper characteristic detection device according to claim 1, wherein, The control unit changes the detection value or the thickness correction according to the material of the clamping part.

12. The paper characteristic detection device according to claim 1, wherein, The paper characteristic detection device includes a storage unit that stores correction coefficients for correcting the detection value based on the width length of the recording medium or the width length of the portion of the recording medium in contact with the clamping part. The control unit obtains the correction coefficient from the storage unit and corrects the detected value.

13. The paper characteristic detection device according to claim 1, wherein, The paper characteristic detection device includes a storage unit that stores a calibration table, which has multiple calibration values ​​that correct the detection value based on the length in the width direction of the recording medium or the length in the width direction of the portion of the recording medium that contacts the clamping part. The control unit obtains the calibration table from the storage unit, and corrects the detection value based on the multiple calibration values ​​in the calibration table.

14. An image forming system, comprising: An image forming apparatus that forms an image on a recording medium; and A paper characteristic detection device is disposed upstream of the image forming apparatus in the transport direction of the recording medium, and detects the characteristics of the recording medium. The paper characteristic detection device includes: The clamping part clamps the recording medium; A paper thickness detection sensor detects the displacement of the recording medium in the thickness direction within the clamping portion; and The control unit calculates the thickness of the recording medium based on the detection value detected by the paper thickness detection sensor. The control unit corrects the detection value or the thickness detected by the paper thickness detection sensor based on the length of the width direction of the recording medium orthogonal to the conveying direction or the length of the width direction of the portion of the recording medium in contact with the clamping part, and obtains the thickness of the recording medium.

15. A computer program product that causes a paper characteristic detection device to perform: The process of detecting the displacement of the recording medium in the thickness direction within the clamping part of the clamp holding the recording medium; The process of obtaining the length of the recording medium in the width direction orthogonal to the conveying direction, or the length of the portion of the recording medium in the width direction that contacts the clamping part; and The process of correcting the detected value or the thickness based on the length in the width direction of the recording medium or the length in the width direction of the portion of the recording medium that contacts the clamping part, thereby obtaining the thickness of the recording medium.

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