Paper winder and paper winding method

Abstract

A paper winding device comprises a first winding core formed on a first arm that rotates around a rotation axis, on which paper is to be wound, a first motor that drives the first winding core, a second winding core formed on a second arm that rotates around a rotation axis, on which paper is to be wound after the first winding core, and a control device that performs rotational control of the first motor and the second motor. In rotational control, the control device performs tension correction control by switching the control mode of the second motor from speed control to torque control and adjusting the torque value of the second motor so that the paper tension is within a target range, when the torque value of the second motor is greater than or equal to a torque reference value, after the paper winding by the first winding core is completed and after the position of the second winding core becomes a position to be wound by the rotation of the second arm.

Description

Technology Field

[0001] The present disclosure relates to a paper winding device. Background Technology

[0002] Patent Document 1 discloses a technique for continuously winding a web, which is a strip-like sheet material such as paper or film, by a plurality of winding rolls. In this prior art, the web is cut when the winding roll on which the web is to be wound is replaced. Specifically, the web is cut while in contact with the outer surface of the winding core on which the web is to be newly wound. Prior art literature

[0003] Japanese Published Patent Application No. 2015-048173 The problem to be solved

[0004] However, when paper is wound continuously using multiple cores, a traverse cutter is sometimes used to cut the paper when changing the winding roll after the winding of the paper by the core is completed. When cutting the paper with a traverse cutter, a situation occurs where both the winding roll and the new core required to wind the paper are winding the paper.

[0005] In this case, when cutting the paper with a traverse cutter, if the new core is not in a suitable operating state for winding the paper, there is a risk that wrinkles or collapse of the paper winding may occur in the paper wound on the new core.

[0006] One objective of the present disclosure is to provide a technology that can improve the stability of paper winding by using a new core when replacing a winding roll. means of solving the problem

[0007] A first aspect of the present disclosure relates to a paper winding device for winding paper. The paper winding device comprises a first winding core formed on a first arm that rotates around a rotation axis, on which paper is to be wound, a first motor for driving the first winding core, a second winding core formed on a second arm that rotates around a rotation axis, on which paper is to be wound after the first winding core, a second motor for driving the second winding core, and a control device for controlling the rotation of the first motor and the second motor. In rotational control, the control device performs tension correction control by adjusting the torque value of the second motor so that the paper tension is within the target range, when the torque value of the second motor is greater than or equal to the torque reference value during the operation of the traverse cutter that cuts the paper near the second winding core after the paper winding by the first winding core is completed and after the position of the second winding core becomes the position where the paper is to be wound by the pivoting of the second arm.

[0008] The second aspect of the present disclosure, in addition to the first aspect, further has the following features. The torque reference value is the torque value of the first motor when the tension of the paper during winding of the first core paper is within the target range.

[0009] A third aspect of the present disclosure, in addition to the second aspect, further has the following features. The torque reference value is additionally a value obtained by adding the mechanical loss of at least the second motor to the torque value of the first motor.

[0010] The fourth aspect of the present disclosure, in addition to the third aspect, further has the following feature: the mechanical loss is periodically updated during the driving of the second motor.

[0011] The fifth aspect of the present disclosure, in addition to the first aspect, further has the following features. In rotational control, the control device further sets the control mode of the first motor to stop driving the first motor after switching the control mode of the second motor from speed control to torque control, and also after the operation of the traverse cutter is completed.

[0012] A sixth aspect of the present disclosure relates to a paper winding method for winding paper. The paper winding method comprises, during the operation of a traverse cutter that cuts paper near a second winding core after the paper is wound by a first winding core formed on a first arm rotating around a rotation axis and after the position of the second winding core formed on a second arm rotating around a rotation axis becomes the position where the paper is wound, determining whether the torque value of a second motor driving the second winding core is greater than or equal to a torque reference value; if the torque value of the second motor is determined to be greater than or equal to the torque reference value, switching the control mode of the second motor from speed control to torque control; and performing tension correction control to adjust the torque value of the second motor so that the tension of the paper is within a target range. Effects of the invention

[0013] According to the present disclosure, when a traverse cutter that cuts paper is in operation, if the torque value of the second motor is greater than or equal to a torque reference value, tension correction control is performed by switching the control mode of the second motor from speed control to torque control and adjusting the torque value of the second motor so that the tension of the paper is within a target range. By doing so, the stability of winding paper with a new core when changing the winding roll can be improved. Brief explanation of the drawing

[0014] FIG. 1 is a drawing for explaining the overview of a paper winding device related to an embodiment. FIG. 2 is a drawing for explaining the overview of a paper winding device related to an embodiment. FIG. 3 is a drawing for explaining a specific example of a paper winding device related to an embodiment. FIG. 4 is a drawing for explaining a specific example of a paper winding device related to an embodiment. FIG. 5 is a flowchart showing a processing example of a paper winding device related to an embodiment. Specific details for implementing the invention

[0015] With reference to the attached drawings, a paper winding device and a paper winding method related to an embodiment of the present disclosure will be described. In addition, common elements in each drawing are given the same reference numeral, and redundant descriptions are omitted.

[0016] 1. Overview

[0017] 1-1. Configuration of the Paper Winding Device

[0018] FIG. 1 is a diagram for explaining the overview of a paper winding device (1) related to an embodiment. The paper winding device (1) is a turret-type device that continuously winds paper (50) by means of a plurality of winding cores. The paper (50) is, for example, thick paper having a thickness of 800 μm. The paper winding device (1) is equipped with a paper winding mechanism (2), a paper cutting part (3), and a control device (100).

[0019] The paper winding mechanism (2) includes arm portions (10) (first arm (10a), second arm (10b), third arm (10c), and fourth arm (10d)). Each of the arms has a mechanism that rotates in at least one direction around a rotation axis (10e) formed at one end of each arm. These arms may have a cross-shaped structure, as shown in FIG. 1(A).

[0020] Each of the arms performs a rotation at a predetermined angle at predetermined timings after the operation of the paper winding device (1) begins. Alternatively, it performs a rotation at a predetermined angle upon receiving a rotation instruction from the control device (100) described later.

[0021] A first coil (11) is formed at the other end of the first arm (10a). Also, a second coil (12) is formed at the other end of the second arm (10b). A guide roller (13) is formed at the other end of the third arm (10c). And, a guide roller (14) is formed at the other end of the fourth arm (10d).

[0022] The first core (11) is the core of the object on which the paper (50) is to be wound. The second core (12) is the core on which the paper (50) is to be wound after the first core (11). The second core (12) is located on the opposite side of the first core (11) via a rotation axis (10e), for example, as shown in FIG. 1(A). When the position of either the first core (11) or the second core (12) is the position on which the paper (50) is to be wound, the paper (50) is wound by said core. The position on which the paper (50) is to be wound is, for example, the position of the first core (11) shown in FIG. 1(A).

[0023] The guide roller (14) guides the paper (50) wound on the first core (11) after the paper (50) is wound on the first core (11), and also between the point where the second core (12) is positioned to be wound on the paper (50) by the turning of the second arm (10b) and the point where the paper (50) is cut. Although not illustrated, the guide roller (13) guides the paper (50) wound on the second core (12) after the paper (50) is wound on the second core (12), and also between the point where the first core (11) is positioned to be wound on the paper (50) by the turning of the first arm (10a) and the point where the paper (50) is cut.

[0024] The paper winding mechanism (2) additionally includes a first motor (21) and a second motor (22). The first motor (21) is a motor that drives the first winding core (11) and is fixedly mounted on the first winding core (11). The second motor (22) is a motor that drives the second winding core (12) and is fixedly mounted on the second winding core (12). The first motor (21) and the second motor (22) receive a command from the control device (100) described later to start or stop driving.

[0025] When the position of either the first core (11) or the second core (12) is a position where paper (50) is to be wound, the winding of paper (50) by the core is realized by driving the motor corresponding to the core.

[0026] The paper cutting section (3) includes a first touch arm (30) and a second touch arm (40). The first touch arm (30) is a mechanical device for pressing the paper (50) against the outer surface of the second core (12) at the time of cutting the paper (50) so that the second core (12) can wind the paper (50) after cutting.

[0027] The first touch arm (30) has a mechanism for pivoting based on a rotation axis (30a) formed at one end of the first touch arm (30). Here, the movement of the first touch arm (30) pivoting clockwise at the point in FIG. 1 is referred to as forward, and the movement of the first touch arm (30) pivoting counterclockwise at the point in FIG. 1 is referred to as backward. The first touch arm (30) moves forward before cutting the paper (50) and moves backward after cutting the paper (50).

[0028] Specifically, the first touch arm (30) advances simultaneously with the completion of the operation of the paper winding mechanism (2), as shown in FIG. 1(B). Also, the first touch arm (30) retracts simultaneously with the completion of cutting the paper (50) by the traverse cutter (40c) described later.

[0029] When the first touch arm (30) moves forward, the paper (50) is pressed against the outer surface of the second core (12) by the nip roll (30b) formed at the other end of the first touch arm (30). This allows the second core (12) to wind the paper (50) after cutting.

[0030] The second touch arm (40) is a mechanical device for cutting paper (50). The second touch arm (40) has a mechanism for pivoting based on a rotation axis (40a) formed at one end of the second touch arm (40). At the point in FIG. 1, the movement of the second touch arm (40) pivoting counterclockwise is referred to as forward, and at the point in FIG. 1, the movement of the second touch arm (40) pivoting clockwise is referred to as backward. The second touch arm (40) moves forward before cutting the paper (50) and moves backward after cutting the paper (50).

[0031] Specifically, the second touch arm (40) advances simultaneously with the completion of the operation of the paper winding mechanism (2), as shown in FIG. 1(B). Also, the second touch arm (40) retracts simultaneously with the completion of cutting the paper (50) by the traverse cutter (40c) described later.

[0032] The second touch arm (40) has a core fixing device (40b) that can insert and fix the second core (12) formed at the other end of the second touch arm (40), and when cutting the paper (50), the second core (12) is fixed by the core fixing device (40b).

[0033] The second touch arm (40) has a traverse cutter (40c) formed between one end of the second touch arm (40) and the other end of the second touch arm (40). The traverse cutter (40c) is a cutter that cuts paper (50). The traverse cutter (40c) is stored in the second touch arm (40) except when cutting paper (50) and is used only when cutting paper (50). An image of the traverse cutter (40c) in use is shown, for example, as in FIG. 1(B).

[0034] The traverse cutter (40c) cuts the paper (50) near the second core (12) after the second core (12) has reached the position where the paper (50) is to be wound. The position where the paper (50) is cut is, for example, between one end of the second touch arm (40) (rotation axis (40a)) and the other end of the second touch arm (40) (core fixing member (40b)), as shown in FIG. 1(B), and is also a position near the second core (12). An overview of the method of cutting the paper (50) by the traverse cutter (40c) will be described later.

[0035] The control device (100) is a controller that performs rotational control of the first motor (21) and the second motor (22). The controller is, for example, a PLC (Programmable Logic Controller). In addition, the control device (100) includes a driver that drives the first motor (21) and the second motor (22). In addition, the control device (100) stores a paper winding program (not shown). By the control device (100) executing the paper winding program, the function of rotational control of the first motor (21) and the second motor (22) is realized.

[0036] The control device (100) is connected to the first motor (21), the second motor (22), the arm section (10), the first touch arm (30), and the second touch arm (40), respectively. Each of the control device (100) and each of the devices is connected, for example, by a cable.

[0037] The control device (100) receives a pivot start flag of at least the second arm (10b) from the arm portion (10). Also, the control device (100) receives a forward start flag of at least the first touch arm (30) from the first touch arm (30). Also, the control device (100) receives a retraction start flag of at least the second touch arm (40) from the second touch arm (40). Details regarding the rotation control of the first motor (21) and the second motor (22) by the control device (100) will be described later.

[0038] 1-2. Example of Traverse Cutter Operation

[0039] FIG. 2 is a diagram for explaining the overview of the cutting method of the traverse cutter (40c) in the paper winding device (1) related to the embodiment. Specifically, FIG. 2 shows a time series of operation examples of the traverse cutter (40c) cutting the paper (50) near the second winding core (12) after the paper (50) is wound by the first winding core (11) and after the position of the second winding core (12) becomes the position where the paper (50) is to be wound by the rotation of the second arm (10b).

[0040] As shown in FIG. 2, the traverse cutter (40c) cuts the paper (50) in a direction perpendicular to the length direction of the paper (50) (cutting direction) while the paper (50) is pressed against the outer surface of the second core (12) by the nip roll (30b). Since the cutting speed of the traverse cutter (40c) is matched to the winding speed of the paper (50), the paper (50) wound on the first core (11) is cut by the traverse cutter (40c) at a diagonal angle of 45 degrees relative to the winding direction.

[0041] Additionally, the traverse cutter (40c) has a range of motion (60) formed in the cutting direction. As shown in FIG. 2, the traverse cutter (40c) cuts the paper (50) according to the range of motion (60). Also, when the width of the paper (50) is W [m] and the speed of the paper (50) wound on the first core (11) is V [m / min], the cutting time of the traverse cutter (40c) is expressed by the following equation (1).

[0042]

[0043] For example, when the width of the paper (50) is 2.01 [m] and the speed of the paper (50) is 20 [m / min], the cutting time of the traverse cutter (40c) is 6.03 [s].

[0044] After the paper (50) is cut by the traverse cutter (40c), each of the two separated pieces of paper (50) is wound onto the first core (11) and the second core (12), respectively. In this way, the winding roll can be replaced after the winding of the paper (50) by the first core (11) is completed while the paper winding device (1) is operated continuously.

[0045] 2. Specific example

[0046] 2-1. Example of Motor Rotation Control

[0047] FIG. 3 is a drawing for explaining a specific example of a paper winding device (1) related to an embodiment. Specifically, FIG. 3 shows an example of rotational control of a first motor (21) and a second motor (22) in a control device (100) of a paper winding device (1). In addition, the processing of the part shown in FIG. 3(A) is performed by a sequential mechanical operation, and control by the control device (100) is not performed. Based on this, an example of rotational control of the first motor (21) and the second motor (22) by the control device (100) will be explained below.

[0048] The control device (100) receives a pivot start flag for the second arm (10b) from the arm part (10) after the completion of winding the paper (50) by the first core (11) at the timing shown in FIG. 3(B).

[0049] Then, the control device (100) sets the control mode of the second motor (22) to drive the second motor (22). Specifically, the control device (100) sets the control mode of the second motor (22) to speed control. Speed ​​control is controlling the rotational speed of the motor to drive it within the range of the target speed.

[0050] When the control mode of the second motor (22) is set to speed control, the driving state of the second motor (22) transitions in the order of a stopped state and an accelerated state. This allows the second motor (22) to be driven. After that, the second motor (22) is controlled so that the speed of the second motor (22) is driven within the range of the target speed.

[0051] Additionally, the control device (100) switches the control mode of the second motor (22) from speed control to torque control during the operation of the traverse cutter (40c), and at a timing when the torque value of the second motor (22) satisfies a predetermined condition. Torque control is a control that drives the motor's generated torque within the range of a target torque.

[0052] During the operation of the traverse cutter (40c), the timing at which the torque value of the second motor (22) satisfies a predetermined condition is, for example, the position shown in FIG. 3(C). The predetermined condition means a condition in which the torque value of the second motor (22) is greater than or equal to a torque reference value. Details regarding the setting of the torque reference value will be described later.

[0053] Here, we consider how the control device (100) determines the timing during the operation of the traverse cutter (40c). The time period during the operation of the traverse cutter (40c) is calculated by the equation (1) described above. Therefore, the control device (100) only needs to determine the start time of the operation of the traverse cutter (40c). The start time of the operation of the traverse cutter (40c) is, for example, the time obtained by adding a predetermined time period (first time period) to the start time of rotation of the second arm (10b) after the completion of winding the paper (50) of the first core (11) (timing shown in FIG. 3(B)). Or, it is the time obtained by adding a predetermined time period (second time period) to the start time of forward movement of the first touch arm (30) (timing shown in FIG. 3(D)).

[0054] In addition, the first time zone and the second time zone may be information of a predetermined time zone or information of a time zone obtained by measurement.

[0055] Based on this, the control device (100) sets the turning start flag of the second arm (10b) received from the second arm (10b) as the turning start time of the second arm (10b). Alternatively, it sets the forward start flag of the first touch arm (30) received from the first touch arm (30) as the forward start time of the first touch arm (30). Then, the control device (100) adds a first time period to the turning start time of the second arm (10b). Alternatively, it adds a second time period to the forward start time of the first touch arm (30). By doing so, the control device (100) can determine the operation start time of the traverse cutter (40c).

[0056] Additionally, the control device (100) performs tension correction control for the second motor (22) during the operation of the traverse cutter (40c) at a timing when the torque value of the second motor (22) satisfies the predetermined conditions described above. That is, at the said timing, the control device (100) performs tension correction control for the second motor (22) while switching the control mode of the second motor (22) from speed control to torque control. Tension correction control is the adjustment of the motor's torque value so that the tension of the paper (50) is within the target range.

[0057] Additionally, the control device (100) sets the control mode of the first motor (21) to stop driving the first motor (21) after switching the control mode of the second motor (22) from speed control to torque control, and also after the operation of the traverse cutter (40c) is completed. Specifically, the control device (100) switches the control mode of the first motor (21) from torque control to stop. When the control mode of the first motor (21) is set to stop, the driving state of the first motor (21) transitions in the order of deceleration state and stop state. By doing so, the driving of the first motor (21) can be stopped.

[0058] Here, consider how the control device (100) determines the time of completion of the operation of the traverse cutter (40c). The time of completion of the operation of the traverse cutter (40c) may be, for example, the time of start of retraction of the second touch arm (40) (timing shown in FIG. 3(E)). The control device (100) sets the retraction start flag of the second touch arm (40) received from the second touch arm (40) as the time of start of retraction of the second touch arm (40). By doing so, the control device (100) can determine the time of completion of the operation of the traverse cutter (40c).

[0059] 2-2. Example of Setting Torque Reference Values

[0060] The control device (100) sets a torque reference value after the second motor (22) starts driving, as shown in FIG. 4. The torque reference value is the torque value of the first motor (21) when the tension of the paper (50) during winding of the first core (11) is within the target range. The torque value of the first motor (21) used to set the torque reference value may be a predetermined data, or it may be data obtained from the first core (11) immediately before the paper (50) is wound onto the second core (12).

[0061] Additionally, the torque reference value may be the value obtained by adding at least the mechanical loss of the second motor (22) to the torque value of the first motor (21). Mechanical loss refers to mechanical loss that depends on the rotational speed of the motor. The mechanical loss varies depending on the individual difference of the second motor (22) and is calculated periodically during the operation of the second motor (22). Also, the mechanical loss used to set the torque reference value is updated periodically.

[0062] Additionally, the control device (100) determines whether the torque value of the second motor (22) is greater than or equal to the torque reference value during the operation of the traverse cutter (40c). If the torque value of the second motor (22) is determined to be greater than or equal to the torque reference value, the control device (100) switches the control mode of the second motor (22) from speed control to torque control, as shown in FIG. 4. Furthermore, the control device (100), while switching the control mode of the second motor (22) from speed control to torque control, also performs tension correction control for the second motor (22), as shown in FIG. 4.

[0063] 2-3. Effects

[0064] In this way, in the paper winding device (1) related to the embodiment, when the torque value of the second motor (22) is greater than or equal to the torque reference value during the operation of the traverse cutter (40c), tension correction control is performed to adjust the torque value of the second motor (22) so that the tension of the paper (50) is within the target range, while switching the control mode of the second motor (22) from speed control to torque control. By doing so, the stability of winding the paper (50) with a new winding core when changing the winding roll can be improved.

[0065] 3. Treatment Example

[0066] FIG. 5 is a flowchart showing an example of processing of a control device (100) in a paper winding device (1) related to an embodiment.

[0067] In step S100, the control device (100) sets the control mode of the second motor (22) to speed control based on the turning start flag of the second arm (10b). After that, the processing proceeds to step S110.

[0068] In step S110, the control device (100) sets a torque reference value for controlling the rotation of the second motor (22). After that, the processing proceeds to step S120.

[0069] In step S120, the control device (100) determines whether the traverse cutter (40c) is in operation. If it is determined that the traverse cutter (40c) is in operation (step S120; Yes), the process proceeds to step S130. Otherwise (step S120; No), the process returns to step S120.

[0070] In step S130, the control device (100) determines whether the torque value of the second motor (22) is greater than or equal to the torque reference value. If it is determined that the torque value of the second motor (22) is greater than or equal to the torque reference value (step S130; Yes), the processing proceeds to step S140. Otherwise (step S130; No), the processing returns to step S130.

[0071] In step S140, the control device (100) switches the control mode of the second motor (22) from speed control to torque control. After that, the processing proceeds to step S150.

[0072] In step S150, the control device (100) performs tension correction control for the second motor (22). After that, the processing proceeds to step S160. In addition, the processing of step S150 is performed simultaneously with the processing of step S140 described above.

[0073] In step S160, the control device (100) switches the control mode of the first motor (21) from torque control to stop. Explanation of the symbols

[0074] 1 : Paper winding device 2: Paper winding mechanism 3: Paper cutting section 10 : Aambu 10a : 1st arm 10b : 2nd arm 10c: 3rd arm 10d : 4th arm 11: First Authority 12: Second Authority 13: Guide roller 21: 1st motor 22: 2nd motor 30: 1st touch arm 30a : Rotation axis 30b: Nip roll 40: 2nd touch arm 40a : Rotation axis 40b : Winding core fixing device 40c: Traverse cutter 50 : Paper 60: Range of motion 100: Control unit

Claims

Claim 1 A paper winding device for winding paper comprises: a first winding core formed on a first arm pivoting around a rotation axis for the purpose of winding the paper; a first motor for driving the first winding core; a second winding core formed on a second arm pivoting around the rotation axis for the purpose of winding the paper after the first winding core; a second motor for driving the second winding core; and a control device for performing rotational control of the first motor and the second motor. In the rotational control, the control device, during the operation of a traverse cutter that cuts the paper near the second winding core after the winding of the paper by the first winding core is completed and after the position of the second winding core becomes the position for winding the paper by pivoting the second arm, if the torque value of the second motor is greater than or equal to a torque reference value, the control mode of the second motor is switched from speed control to torque control. A paper winding device configured to perform tension correction control to adjust the torque value of the second motor so that the tension of the paper is within a target range, wherein the torque reference value is the torque value of the first motor when the tension of the paper is within the target range during the winding of the paper of the first core immediately before the paper is wound onto the second core. Claim 2 delete Claim 3 A paper winding device for winding paper comprises: a first winding core formed on a first arm pivoting around a rotation axis for the purpose of winding the paper; a first motor for driving the first winding core; a second winding core formed on a second arm pivoting around the rotation axis for the purpose of winding the paper after the first winding core; a second motor for driving the second winding core; and a control device for performing rotational control of the first motor and the second motor. In the rotational control, the control device, during the operation of a traverse cutter that cuts the paper near the second winding core after the winding of the paper by the first winding core is completed and after the position of the second winding core becomes the position for winding the paper by pivoting the second arm, if the torque value of the second motor is greater than or equal to a torque reference value, the control mode of the second motor is switched from speed control to torque control. A paper winding device configured to perform tension correction control to adjust the torque value of the second motor so that the tension of the paper is within a target range, wherein the torque reference value is a value obtained by adding at least the mechanical loss of the second motor to the torque value of the first motor immediately before the paper is wound onto the second core. Claim 4 A paper winding device according to claim 3, characterized in that the mechanical loss is periodically updated during the operation of the second motor. Claim 5 A paper winding device according to any one of claims 1, 3, and 4, characterized in that, in the rotational control, the control device is further configured to set the control mode of the first motor to stop driving the first motor after switching the control mode of the second motor from speed control to torque control, and also after the operation of the traverse cutter is completed. Claim 6 A paper winding method for winding paper, comprising: determining whether the torque value of a second motor driving the second winding core is greater than or equal to a torque reference value; switching the control mode of the second motor from speed control to torque control; and performing tension correction control to adjust the torque value of the second motor so that the tension of the paper is within a target range, wherein the torque reference value is the first winding core of the object to be wound, formed on a first arm pivoting around a rotation axis, after the completion of winding the paper by a first winding core of the object to be wound the paper formed on a first arm pivoting around the rotation axis, and after the position of the second winding core of the object to be wound the paper following the first winding core formed on the second arm pivoting around the rotation axis becomes the position to be wound the paper, wherein the torque reference value is the first winding core immediately before the paper is wound on the second winding core A paper winding method characterized by the torque value of a first motor driving a first winding core when the tension of the paper during winding is within the target range. Claim 7 A paper winding method for winding paper, comprising: determining whether the torque value of a second motor driving the second winding core is greater than or equal to a torque reference value; switching the control mode of the second motor from speed control to torque control; and performing tension correction control to adjust the torque value of the second motor so that the tension of the paper is within a target range, wherein the torque reference value is the first winding core formed on a first arm rotating around a rotation axis after the completion of winding of the paper by a first winding core of an object to be wound, and after the position of the second winding core of an object to be wound after the first winding core formed on a second arm rotating around the rotation axis becomes the position to be wound of the paper, wherein the torque reference value is the first winding core immediately before the paper is wound on the second winding core A paper winding method characterized by the torque value of a first motor that drives the paper being the sum of the mechanical loss of at least the second motor.

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