Sheet pressure bonding device

Abstract

To provide a sheet pressure bonding device enabling the operation in a short time.SOLUTION: A sheet pressure bonding device 100 comprises a pressure bonding unit 4 that performs pressure bonding of a sheet of a single sheet. The pressure bonding unit 4 comprises a pair of pressure rollers 6, 7 that press the sheet, and heating devices 8, 9 separated from at least one of the pressure rollers 6 and 7 to heat the pressure roller. At least the surface of the pressure rollers 6, 7 is made of metals. The heating devices 8, 9 heat the pressure rollers 6, 7 by electromagnetic induction.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a sheet pressing device. [Background technology]

[0002] A pressure-bonded print is used in which recording medium sheets are overlapped and pressure-bonded. An example of a pressure-bonded print is a pressure-bonded postcard. To manufacture a pressure-bonded print, a pressure-bonding device having a pressure roller and a heat source is used (see, for example, Patent Document 1). The pressure-bonding device uses a heat source to heat the recording medium sheet, and presses the recording medium sheet with the pressure roller. This produces a pressure-bonded print in which the recording medium sheet is pressure-bonded so that it can be peeled off. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-152378 A Summary of the Invention [Problem to be solved by the invention]

[0004] The above-mentioned pressing device requires a long time for operation because it takes time to preheat the pressure roller.

[0005] An object of one aspect of the present invention is to provide a sheet pressing device that can operate in a short time. [Means for solving the problem]

[0006] One aspect of the present invention is a sheet pressing device having a pressing unit that presses a single-piece sheet, the pressing unit including a pair of pressure rollers that press the sheet, and a heating device that is spaced apart from at least one of the pressure rollers and heats the pressure roller, the pressure roller having at least a surface formed of metal, The heating device heats the pressure roller by electromagnetic induction, thereby providing a sheet pressing device.

[0007] It is preferable that the outer circumferential length of the pressure roller is equal to or greater than the length of the sheet.

[0008] It is preferable that the sheet pressing device further includes a temperature measuring unit that measures the surface temperature of one of the pair of pressure rollers as the measurement object, the heating device is provided on each of the pressure rollers, and the pressure roller as the measurement object is closer to the heating device than the other pressure roller.

[0009] It is preferable that the sheet pressing device further includes a control unit that controls the heating temperature of the heating device.

[0010] It is preferable that the heating device, which heats one of the pair of pressure rollers, is located at an angle of 30 degrees or more and 100 degrees or less around the central axis of the pressure roller with respect to a reference line extending in a direction in which the pressure roller moves away from the other pressure roller.

[0011] At least one of the pair of pressure rollers is movable in a direction in which the pair of pressure rollers move apart, and when the separation distance between the pair of pressure rollers is at its maximum, it is preferable that the separation distance between the pressure roller and the heating device that heats the pressure roller is 0.2 mm or more and 20 mm or less. Effect of the Invention

[0012] According to one aspect of the present invention, it is possible to provide a sheet pressing device that can operate in a short time. [Brief description of the drawings]

[0013] [Figure 1] 1 is a configuration diagram of a sheet pressure-bonding device according to a first embodiment. FIG. [Diagram 2] 2 is a configuration diagram of a pressing unit of the sheet pressing device according to the first embodiment. FIG. [Diagram 3] 2 is a configuration diagram of a pressing unit of the sheet pressing device according to the first embodiment. FIG. [Figure 4] 3 is a configuration diagram of a pressure roller of the sheet pressure bonding device according to the first embodiment. FIG. [Diagram 5] FIG. 2 is a configuration diagram of a first heating device of the sheet pressure-bonding device according to the first embodiment. [Figure 6] FIG. 3 is a configuration diagram of a second heating device of the sheet pressure-bonding device according to the first embodiment. [Figure 7] 11 is a configuration diagram of a pressing unit of a sheet pressing device according to a second embodiment. FIG. [Figure 8] 13 is a configuration diagram of a pressing unit of a sheet pressing device according to a third embodiment. FIG. [Figure 9] 13 is a configuration diagram of a pressing unit of a sheet pressing device according to a fourth embodiment. FIG. [Figure 10] FIG. 2 is a development view of the front surface of the base sheet. [Figure 11] FIG. 2 is a development view of the back surface of the base sheet. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a sheet pressing device according to an embodiment of the present invention will be described in detail with reference to the drawings.

[0015] [Sheet compression device] (First embodiment) FIG. 1 is a configuration diagram of a sheet pressing device 100 according to the first embodiment. FIG. 2 is a configuration diagram of the pressing unit 4 as viewed from the side. FIG. 2 is a view as viewed from a direction parallel to the central axes of the pressure rollers 6 and 7. FIG. 3 is a configuration diagram of the pressing unit 4 as viewed from the front side. FIG. 4 is a configuration diagram of the pressure rollers 6 and 7. FIG. 5 is a configuration diagram of a first heating device 8. FIG. 6 is a configuration diagram of a second heating device 9.

[0016] As shown in FIG. 1, the sheet pressing device 100 includes a hopper unit 1, a sheet supply unit 2, a sheet folding unit 3, a pressing unit 4, and a stacker unit 5.

[0017] The hopper section 1 holds a plurality of base sheets 10. The base sheet 10 is a single-piece sheet. The hopper section 1 can hold a plurality of base sheets 10 in a stacked state. The sheet supply unit 2 feeds the base sheets 10 held in the hopper unit 1 one by one. The sheet folding unit 3 folds the base sheet 10. The sheet folding unit 3 overlaps the base sheet 10 so as to fold it in half or in thirds, for example. The base sheet 10 becomes a folded sheet 20 by being folded. The folded sheet 20 is simply referred to as a "sheet 20".

[0018] As shown in Figures 2 and 3, the pressing unit 4 includes a pair of pressure rollers 6, 7 and a pair of heating devices 8, 9. The pressure rollers 6, 7 are a first pressure roller 6 and a second pressure roller 7, respectively. The pressure rollers 6, 7 are arranged in parallel so that their rotation axes are parallel. The outer peripheral surface (surface) of the first pressure roller 6 is a roller surface 6a (pressure surface). The outer peripheral surface (surface) of the second pressure roller 7 is a roller surface 7a (pressure surface).

[0019] At least the roller surfaces 6a, 7a of the pressure rollers 6, 7 are made of metal. The pressure rollers 6, 7 are made of, for example, solid metal. That is, the pressure rollers 6, 7 have a solid structure made entirely of metal. Since the pressure rollers 6, 7 have a solid structure, the heat capacity is large. Therefore, local temperature deviations can be reduced. Therefore, the pressure rollers 6, 7 can sufficiently heat the entire sheet 20.

[0020] Examples of metals constituting the pressure rollers 6, 7 include iron, stainless steel, nickel, aluminum, and copper. The metals constituting the pressure rollers 6, 7 may be alloys containing one or more of these metals. If the pressure rollers 6, 7 are made of a magnetic material such as iron, the temperature rise speed can be increased when heating by electromagnetic induction. The roller surfaces 6a, 7a are, for example, mirror-finished.

[0021] The pressure rollers 6 and 7 are preferably arranged such that the roller surfaces 6a and 7a are not in contact with each other. The distance between the first pressure roller 6 and the second pressure roller 7 is smaller than the thickness of the sheet 20 (e.g., a postcard folded in three) before it is pressed.

[0022] The outer circumferential length of the pressure rollers 6, 7 is preferably equal to or greater than the length of the sheet 20. The "length of the sheet 20" refers to the length of the sheet 20 in the conveying direction in the pressure bonding section 4 (the length in the left-right direction in FIG. 4). When the outer circumferential length of the pressure rollers 6, 7 is equal to or greater than the length of the sheet 20, the pressure rollers 6, 7 at a high temperature can be brought into contact with the entire length of the sheet 20, so that the sheet 20 can be heated sufficiently. In contrast, if the outer circumferential length of the pressure rollers 6, 7 is shorter than that of the sheet 20, a portion of the roller surface 6a, 7a of the pressure rollers 6, 7 will come into contact with the sheet 20 multiple times, and the temperature of that portion of the roller surface 6a, 7a may become lower.

[0023] The outer diameter of the pressure rollers 6, 7 is preferably, for example, 100 mm or more. When the outer diameter of the pressure rollers 6, 7 is in this range, curling of the sheet 20 can be suppressed. When the outer diameter of the pressure rollers 6, 7 is in this range, the temperature can be maintained high, so that high-speed pressing can be handled. When the outer diameter of the pressure rollers 6, 7 is in this range, the strength of the pressure rollers 6, 7 is sufficient, so deformation or movement of the pressure roller in the direction of releasing the pressure hardly occurs. In addition, when the outer diameter of the pressure rollers 6, 7 is 100 mm or more, the outer periphery length is about 314 mm or more, so that, for example, when the sheet 20 is A4 size (length 297 mm), the high-temperature pressure rollers 6, 7 can be brought into contact with the entire length of the sheet 20. Therefore, the sheet 20 can be sufficiently heated.

[0024] The outer diameter of the pressure rollers 6, 7 is preferably, for example, 150 mm or less. When the outer diameter of the pressure rollers 6, 7 is in this range, the curvature of the outer peripheral surface is large and the area involved in the pressing is small, so that sufficient pressure can be applied to the sheet 20. When the outer diameter of the pressure rollers 6, 7 is in the above range, the curvature of the outer peripheral surface is large, so that the sheet 20 is less likely to stick to the pressure rollers 6, 7. Therefore, sheet jams (sheet clogging) are less likely to occur.

[0025] 4, the pressure rollers 6, 7 are rotatable in opposite directions, and the sheet 20 is pulled between the pressure rollers 6, 7 by the rotational force. The pressure rollers 6, 7 sandwich the sheet 20 between the roller surfaces 6a, 7a and pressurize it in the thickness direction. As a result, the pressure rollers 6, 7 releasably adhere the sheet 20.

[0026] As shown in FIG. 2 and FIG. 3, the heating devices 8 and 9 are a first heating device 8 and a second heating device 9, respectively. The first heating device 8 uses electromagnetic induction to heat the first pressure roller 6. The first heating device 8 includes, for example, a heating unit 23 and a control unit 24. 5, the heating unit 23 has a core 21 and a work coil 22. The heating unit 23 is disposed across the length of the first pressure roller 6, facing the roller surface 6a of the first pressure roller 6 (see FIGS. 2 and 3).

[0027] The core 21 is formed of, for example, a ferromagnetic material. The core 21 includes a base 21A, a central core portion 21B, and two side core portions 21C. The central core portion 21B protrudes from the center of the base 21A in a direction perpendicular to the base 21A. The two side core portions 21C protrude in a direction perpendicular to the base 21A at intervals from the central core portion 21B. The protruding direction of the central core portion 21B and the side core portions 21C is a direction approaching the first pressure roller 6. The work coil 22 is formed, for example, by winding a Litz wire around the central core portion 21B.

[0028] When a high-frequency current is applied to the work coil 22, a magnetic flux 25 is generated. The magnetic flux 25 passes, for example, from the central core portion 21B through the base portion 21A and the side core portion 21C to the outside of the core 21 and then returns to the central core portion 21B. The magnetic flux 25 passes through the inside of the first pressure roller 6. An eddy current is generated inside the first pressure roller 6 by electromagnetic induction. The first pressure roller 6 is heated by eddy current loss (Joule heat) and hysteresis loss. In this way, the heating devices 8 and 9 can heat the pressure rollers 6 and 7 from the outside without contact.

[0029] The heating temperature of the sheet 20 by the heating devices 8 and 9 may be, for example, 50° C. or higher. By setting the heating temperature within this range, the sheet 20 can be pressed and peeled off. The heating temperature may be, for example, 90° C. or lower. By setting the heating temperature within this range, the sheet 20 can be pressed and peeled off.

[0030] 6, the second heating device 9 includes a heating unit 23, similar to the first heating device 8. The heating unit 23 heats the second pressure roller 7 by electromagnetic induction.

[0031] As shown in Fig. 2, reference lines S1 and S2 are defined. Reference line S1 extends in a direction in which the first pressure roller 6 moves away from the second pressure roller 7. Reference line S2 extends in a direction in which the second pressure roller 7 moves away from the first pressure roller 6. The first heating device 8 is located at a position where an angle θ1 about the central axis C1 of the first pressure roller 6 is about 45 degrees with respect to the reference line S1. The second heating device 9 is located at a position where an angle θ2 about the central axis C2 of the second pressure roller 7 is about 90 degrees with respect to the reference line S2.

[0032] The control unit 24 controls the heating conditions of the heating devices 8 and 9. The control unit 24 can control, for example, the heating temperature of the pressure rollers 6 and 7 by the heating devices 8 and 9. Therefore, the control unit 24 can switch between the presence and absence of heating by the heating devices 8 and 9. Therefore, when a sheet 20 that requires heating is used, the pressure rollers 6 and 7 can be heated by the heating devices 8 and 9. When a general sheet (a sheet that does not require heating) is used, the pressing unit 4 can be operated without heating by the heating devices 8 and 9. In this way, the sheet pressing device 100 can select processing conditions according to the characteristics of multiple types of sheets.

[0033] 10 and 11 show an example of a base sheet to be pressure-bonded by the sheet pressure-bonding device 100. Fig. 10 is a development of the front side of the base sheet. Fig. 11 is a development of the back side of the base sheet. The base sheet is, for example, a postcard 91 folded in three.

[0034] The tri-folded postcard 91 is composed of a base sheet 92 that is three times the size of a standard postcard. The tri-folded postcard 91 is divided into three areas by fold lines 93 (93a, 93b). The front surface of the left side area A has destination information 94 printed thereon, such as the recipient's name and address. The back surface of the left side area A, both sides of the central area B, and the front surface of the right side area C of the base sheet 92 have concealed information printed thereon 95. A peelable adhesive layer 96 is formed on the entire front surfaces of the central area B and the right side area C, and on the entire back surfaces of the left side area A and the central area B. The adhesive layer 96 may be capable of temporarily adhering the two overlapping surfaces with weak adhesive strength. Depending on the application, it is also possible to change the coating concentration of the adhesive layer, change the adhesive material, or adjust the pressure to be applied, thereby making it possible to adhere the base sheet in a manner that makes it difficult to peel off.

[0035] The tri-fold postcard 91 is folded into a Z-shape at the fold lines 93a and 93b, and the adhesive layers 96 of the overlapping surfaces of each section are overlapped to form a folded sheet. Pressure is applied to this folded sheet by the pressure rollers 6 and 7. As a result, the overlapping surfaces of the folded sheet are peelably bonded to each other via the adhesive layers 96 (see FIG. 4).

[0036] [Effects of the sheet pressure-bonding device of the first embodiment] The sheet pressing device 100 of this embodiment includes heating devices 8 and 9 that heat the pressure rollers 6 and 7 by electromagnetic induction. The heating devices 8 and 9 have higher thermal efficiency than heating devices of other types (for example, heating by a heater inside the roller). Therefore, the temperature rise speed is fast. For example, the pressure rollers 6 and 7 can be heated to a high temperature (for example, 50°C to 80°C) in a few minutes. Therefore, the sheet pressing device 100 can operate in a short time.

[0037] The heating devices 8 and 9 heat by electromagnetic induction, and therefore can quickly restore the temperature of the pressure rollers 6 and 7 that have been cooled by contact with the sheet 20. The heating devices 8 and 9 also have the advantage of being highly thermally efficient, making it possible to reduce power consumption.

[0038] The heating devices 8, 9 heat the pressure rollers 6, 7 by electromagnetic induction, so temperature control is easier than with heating devices that use other methods (for example, heating by a heater inside the roller). The heating devices 8, 9 use electromagnetic induction heating, so they are also suitable in terms of safety when using large currents. The heating devices 8, 9 can heat the pressure rollers 6, 7 without contact, so they can be easily added to existing sheet pressing devices. Therefore, they are also suitable in terms of the manufacturing costs of the sheet pressing device.

[0039] The heating devices 8, 9 are separate from the pressure rollers 6, 7 and heat the pressure rollers 6, 7 from the outside without contact, so that the roller surfaces 6a, 7a of the pressure rollers 6, 7 can be heated sufficiently compared to heating devices using other methods (for example, heating using a heater inside the roller).

[0040] [Sheet compression device] (Second embodiment) Fig. 7 is a configuration diagram of the pressure-bonding unit 204 of the sheet pressure-bonding device 200 according to the second embodiment. Fig. 7 is a configuration diagram of the pressure-bonding unit 204 as viewed from the side. The same reference numerals are used for configurations common to other embodiments, and description thereof will be omitted.

[0041] As shown in FIG. 7, the first heating device 208 is installed above the first pressure roller 6. The second heating device 209 is installed below the second pressure roller 7. The pressure rollers 6, 7 can move toward each other and away from each other. The pressure rollers 6, 7 can move up and down in FIG. 7, and the height positions can be adjusted. In FIG. 7(A), the first pressure roller 6 is at the lowermost position (lowest position). The second pressure roller 7 is at the uppermost position (highest position). Therefore, the separation distance G1 between the pressure rollers 6, 7 is at the minimum value. The separation distance L1 between the first pressure roller 6 and the first heating device 208 is at the maximum value.

[0042] In Fig. 7(B), the first pressure roller 6 is at the highest position (highest position). The second pressure roller 7 is at the lowest position (lowest position). Therefore, the separation distance G2 between the pressure rollers 6, 7 is at a maximum value. The separation distance L2 between the first pressure roller 6 and the first heating device 208 is at a minimum value.

[0043] It is desirable that the separation distance L2 between the first pressure roller 6 and the first heating device 208 when the separation distance between the pressure rollers 6, 7 is at its maximum value be 0.2 mm or more and 20 mm or less. If the separation distance L2 is 0.2 mm or more, it is possible to prevent foreign matter (dust, etc.) from accumulating in the gap between the pressure rollers 6, 7. If the separation distance L2 is 20 mm or less, it is possible to increase the efficiency of heat transfer from the first heating device 208 to the first pressure roller 6.

[0044] In this embodiment, both pressure rollers 6 and 7 are movable toward and away from each other, but only one of the pair of pressure rollers may be movable toward and away from the other pressure roller. For example, only the second pressure roller 7 of the pressure rollers 6 and 7 may be movable in the vertical direction. That is, the sheet pressing device may be such that at least one of the pressure rollers is movable toward and away from the other pressure roller.

[0045] When the second pressure roller 7 of the pressure rollers 6, 7 is movable in the vertical direction, it is desirable that the distance between the second pressure roller 7 and the second heating device 209 when the distance between the pressure rollers 6, 7 is at its maximum value be 0.2 mm or more and 20 mm or less.

[0046] [Sheet compression device] (Third embodiment) Fig. 8 is a configuration diagram of a pressure-bonding unit 304 of a sheet pressure-bonding device 300 according to the third embodiment. Fig. 8 is a configuration diagram of the pressure-bonding unit 304 as viewed from the side. Configurations common to other embodiments are given the same reference numerals and descriptions thereof will be omitted.

[0047] As shown in Fig. 8(A), the first pressure roller 6 is in the lowermost position. The first heating device 308 is closest to the first pressure roller 6 at the center in the height direction (closest point C3). The first heating device 308 is a heating device that heats the first pressure roller 6. In Fig. 8(B), the first pressure roller 6 is in the uppermost position.

[0048] The first heating device 308 is located at an angle θ1 around the central axis of the first pressure roller 6 with respect to the reference line S1. The angle θ1 represents the position of the closest point C3 of the first heating device 308 with respect to the reference line S1. The closest point C3 of the first heating device 308 is the point closest to the first pressure roller 6. The angle θ1 is preferably 30 degrees or more and 100 degrees or less. The angle θ1 may be 60 degrees or more and 100 degrees or less.

[0049] 8(A) and 8(B), when the angle θ1 is 30 degrees or more, the separation distance L between the first pressure roller 6 and the first heating device 308 can be kept small even when the vertical position of the first pressure roller 6 is adjusted. When the angle θ1 is 100 degrees or less, the separation distance L between the first pressure roller 6 and the first heating device 308 can be kept small even when the vertical position of the first pressure roller 6 is adjusted. Therefore, the first heating device 308 can efficiently heat the first pressure roller 6 regardless of the vertical position of the first pressure roller 6.

[0050] 8(A), in this embodiment, the angle θ1 is approximately 90 degrees. Therefore, the first heating device 308 is positioned to the side of the first pressure roller 6. With this configuration, even if the vertical position of the first pressure roller 6 is adjusted, the separation distance L between the first pressure roller 6 and the first heating device 308 can be maintained approximately constant.

[0051] [Sheet compression device] (fourth embodiment) Fig. 9 is a configuration diagram of a pressing unit 404 of a sheet pressing device 400 according to the fourth embodiment. Fig. 9 is a configuration diagram of the pressing unit 404 as viewed from the side. Configurations common to other embodiments are given the same reference numerals and descriptions thereof will be omitted.

[0052] 9, the sheet pressing device 400 includes a temperature measuring unit 401 that measures the surface temperature of one of the pressure rollers 6, 7 (first pressure roller 6). The temperature measuring unit 401 is disposed facing the roller surface 6a of the first pressure roller 6 and spaced apart from the roller surface 6a. The first pressure roller 6 is the object of measurement by the temperature measuring unit 401.

[0053] Temperature measuring unit 401 is installed at a position where angle θ1 with respect to reference line S1 is about 45 degrees, for example. First pressure roller 6 and second pressure roller 7 are the same in material, shape, outer diameter, and the like.

[0054] The first heating device 408 is installed above the first pressure roller 6. The second heating device 409 is installed below the second pressure roller 7. L3 is the separation distance between the first pressure roller 6 and the first heating device 408. L4 is the separation distance between the second pressure roller 7 and the second heating device 409.

[0055] When the pressure rollers 6 and 7 are farthest apart (when the separation distance between the pressure rollers 6 and 7 reaches the maximum value), it is desirable that the separation distance L3 between the first pressure roller 6 and the first heating device 408 is smaller than the separation distance L4 between the second pressure roller 7 and the second heating device 409. That is, it is preferable that "L3 < L4" holds. In other words, it is preferable that the first pressure roller 6 is closer to the corresponding heating device 408 than the second pressure roller 7.

[0056] When "L3 < L4" is satisfied, the distance from the heating device 409 increases in the second pressure roller 7 where the temperature is not measured. Therefore, in the second pressure roller 7, it is possible to suppress the temperature from becoming higher than that of the first pressure roller 6. Thus, safety can be enhanced. Since the sheet pressing device 400 is provided with the temperature measurement unit 401 only on one of the pressure rollers 6 and 7 (the first pressure roller 6), temperature management becomes easier compared to the case of measuring the temperatures of both pressure rollers 6 and 7. Since the sheet pressing device 400 is provided with the temperature measurement unit 401 only on one of the pressure rollers 6 and 7 (the first pressure roller 6), the manufacturing cost can be suppressed compared to the case of providing temperature measurement units on both pressure rollers 6 and 7.

[0057] As described above, the embodiments of the present invention have been explained. However, each configuration and their combinations in the embodiments are examples, and additions, omissions, substitutions, and other changes of the configuration are possible without departing from the spirit of the present invention. Also, the present invention is not limited by the embodiments. The base sheet shown in Fig. 10 and Fig. 11 is a Z-shaped tri-fold postcard, but the folding form of the base sheet is not limited to tri-fold. The base sheet may be a V-shaped bi-fold sheet. The folding form may be bi-fold, tri-fold, or quadruple, depending on the application. The base sheet may be a structure in which multiple sheets are overlapped.

[0058] In the sheet pressing device 100 shown in FIG. 1, multiple base sheets 10 held in a hopper section 1 are supplied to a sheet folding section 3, but the sheet pressing device may also be configured to supply the base sheets as a continuous sheet, cut the continuous sheet into single-piece sheets, and then supply the sheets to the sheet folding section 3.

[0059] The pressure roller may be made of metal only in a depth region (surface region) including the roller surface (surface). It is desirable that at least the roller surface of both of the pair of pressure rollers is made of metal, but at least the roller surface of only one of the pair of pressure rollers may be made of metal. In other words, the pressing portion may be made of metal at least in the roller surface of at least one of the pressure rollers. [Explanation of symbols]

[0060] 4,204,304,404...pressure bonding section, 6...first pressure roller (pressure roller), 7...second pressure roller (pressure roller), 8,208,308...first heating device (heating device), 9,409...second heating device (heating device), 20...folded sheet (sheet), 24...control section, 100,200,300,400...sheet pressure bonding device, 401...temperature measurement section, C1...center axis of first pressure roller, C2...center axis of second pressure roller

Claims

1. A sheet pressing device including a pressing unit that presses a single-piece sheet, The crimping portion is A pair of pressure rollers for pressing the sheet; a heating device spaced apart from at least one of the pressure rollers and configured to heat the pressure roller; At least a surface of the pressure roller is made of metal, the heating device heats the pressure roller by electromagnetic induction; Sheet crimping device.

2. The outer circumferential length of the pressure roller is equal to or greater than the length of the sheet.

2. The sheet pressing device according to claim 1.

3. a temperature measuring unit for measuring a surface temperature of one of the pair of pressure rollers as a measurement target, The heating device is provided for each of the pressure rollers, The pressure roller to be measured is closer to the heating device than the other pressure roller.

2. The sheet pressing device according to claim 1.

4. Further comprising a control unit for controlling the heating temperature of the heating device.

2. The sheet pressing device according to claim 1.

5. the heating device for heating one of the pair of pressure rollers is located at an angle of 30 degrees or more and 100 degrees or less around the central axis of the pressure roller with respect to a reference line extending in a direction in which the pressure roller moves away from the other pressure roller; 2. The sheet pressing device according to claim 1.

6. At least one of the pair of pressure rollers is movable in a direction in which the pair of pressure rollers move away from each other, When the distance between the pair of pressure rollers is maximum, the distance between the pressure roller and the heating device for heating the pressure roller is 0.2 mm or more and 20 mm or less.

2. The sheet pressing device according to claim 1.

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