Printing device, and drive control method of printing device

Abstract

The present application provides a printing device that appropriately controls the tension of a label sheet and the tension of a backing sheet and appropriately controls the conveying speed of the label sheet, and a driving control method of the printing device. The printing device includes a first roller disposed upstream of a peeling section, a second roller disposed downstream of the peeling section, a first motor that drives the first roller, a second motor that drives the second roller, and a control section that includes a first motor control section that adjusts a first voltage applied to the first motor based on information related to the conveying speed and the conveying acceleration of the label sheet so that the load torque of the first motor becomes a target torque, and a second motor control section that feedback-controls a second voltage applied to the second motor based on information related to the conveying speed of the backing sheet so that the conveying speed of the backing sheet becomes a target conveying speed.

Description

Technical Field

[0001] This invention relates to a printing apparatus and a method for driving and controlling the printing apparatus. Background Technology

[0002] A printer with a label peeling mechanism is known.

[0003] For example, the label printer described in Patent Document 1 includes: a print head that prints on label paper; a conveyor roller that is positioned upstream of the print head on the label paper conveying path and conveys the label paper downstream; a peeling roller that is positioned downstream of the print head and peels the label off the backing paper by conveying the backing paper in a direction different from the label's travel direction; and a control unit that controls the rotation of the conveyor roller and the peeling roller. The control unit controls the current value supplied to the peeling motor that rotates the peeling roller so that the conveying force of the peeling roller conveying the backing paper is above the minimum force required to peel off the label and exceeds the maximum frictional force between the peeling roller and the backing paper. The maximum frictional force and the maximum frictional force between the conveyor roller and the label paper are set such that the conveying force of the peeling roller is below the conveying force of the peeling roller, which sets the label paper conveying error generated by the conveyor roller to an allowable value.

[0004] However, in the label printer described in Patent Document 1, the tension of the liner paper is controlled by the friction between the peeling roller and the liner paper. Therefore, the tension of the liner paper depends on the coefficient of friction, the winding angle, and the pressing force, making it difficult to stabilize. Unstable liner paper tension can lead to poor peeling due to decreased tension and poor paper feeding accuracy due to increased tension.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2021-28117 Summary of the Invention

[0006] One embodiment of the printing apparatus includes: a printhead for printing on label paper on which a label is pasted onto backing paper; a peeling section for peeling the label off the backing paper; a first roller disposed upstream of the peeling section on the label paper transport path; a second roller disposed downstream of the peeling section on the backing paper transport path; a first drive unit for driving the first roller; a second drive unit for driving the second roller; and a control unit for controlling the first drive unit and the second drive unit, wherein the control unit adjusts the voltage applied to the first drive unit to a predetermined value for the load torque of the first drive unit based on information related to the transport speed and transport acceleration of the label paper, and provides feedback control to the voltage applied to the second drive unit to a predetermined speed for the transport speed of the backing paper based on information related to the transport speed of the backing paper.

[0007] In another embodiment of the driving control method for a printing apparatus, the printing apparatus includes: a print head for printing on label paper on which a label is pasted onto backing paper; a peeling section for peeling the label off the backing paper; a first roller disposed upstream of the peeling section on the label paper transport path; a second roller disposed downstream of the peeling section on the backing paper transport path; a first drive unit for driving the first roller; a second drive unit for driving the second roller; and a control unit for controlling the first drive unit and the second drive unit. The driving control method for the printing apparatus includes: a first step in which the control unit adjusts the voltage applied to the first drive unit to a predetermined value based on information related to the transport speed and transport acceleration of the label paper; and a second step in which the control unit performs feedback control on the voltage applied to the second drive unit to a predetermined speed based on information related to the transport speed of the backing paper. Attached Figure Description

[0008] Figure 1 This diagram illustrates an example of the overall structure of the label printer involved in this embodiment.

[0009] Figure 2 This is a diagram illustrating an example of the structure of the main parts of a label printer.

[0010] Figure 3 This is a diagram illustrating an example of the structure of the control unit.

[0011] Figure 4A graph showing an example of the rotational speed, voltage, and load torque of the first motor.

[0012] Figure 5 A flowchart illustrating an example of the control of the first motor.

[0013] Figure 6 A flowchart illustrating an example of the control of a second motor. Detailed Implementation

[0014] Hereinafter, this embodiment will be described with reference to the accompanying drawings.

[0015] Figure 1 The diagram shows an example of the overall structure of the label printer 1 according to this embodiment.

[0016] Label printer 1 is a printer that uses label paper P as a printing medium, for example, by inkjet printing, to print text, images, graphics, etc.

[0017] Label printer 1 corresponds to an example of a "printing device".

[0018] The label paper P has a backing paper Pa and multiple labels Pb. The backing paper Pa is a continuous strip of paper. The labels Pb are adhered to the surface of the backing paper Pa, and the labels Pb are peelable and cut to predetermined sizes at equal intervals along the length of the backing paper Pa. The backing paper Pa and the labels Pb can be made of paper or other materials. The label paper P is placed in the label printer 1 as a roll of paper R wound into a roll shape.

[0019] The label printer 1 includes a printing section 3 and a peeling section 4, which are the main body of the label printer 1. The peeling section 4 may be integrally formed with the printing section 3, or it may be a component that can be detached from the printing section 3.

[0020] The peeling section 4 is a device that performs the process of peeling the label Pb from the backing paper Pa on the label paper P printed by the printing section 3; it is also called a peeling machine. The label printer 1 is capable of performing a non-peeling mode in which the printed label paper P is discharged while the label Pb remains adhered to the backing paper Pa, and a peeling mode in which the printed label Pb is discharged after being peeled from the backing paper Pa. In this embodiment, the peeling mode will be described.

[0021] The printing unit 3 prints each label Pb on the label paper P based on commands sent by a computer (not shown) and printing data, and through the print head 8. Furthermore, the printing unit 3 transports the label paper P along the transport path of the label paper P. In the following text, the upstream and downstream of the transport path will sometimes be referred to simply as upstream and downstream.

[0022] like Figure 1 As shown, the printing unit 3 includes: a storage unit 29, an unwinding roller 10, a first roller 11, an impression plate 12, a guide member 13, a printing head 8, and a control unit 40.

[0023] The storage section 29 is a space for storing the roll of paper R, and the label paper P is unwound from the roll of paper R placed in the storage section 29. The unwinding roller 10 consists of a pair of rollers arranged opposite each other, and conveys the label paper P unwound from the roll of paper R downstream.

[0024] The first roller 11 consists of a pair of rollers arranged opposite each other, which clamp the label paper P being conveyed by the unwind roller 10 and convey it toward the downstream printing head 8.

[0025] The unwinding roller 10 is connected to an unwinding motor (not shown) and rotates under the power of the unwinding motor. The first roller 11 is connected to the first motor M1 directly or via gears, belts, etc., and rotates under the power of the first motor M1.

[0026] The first motor M1 corresponds to an example of the "first drive unit".

[0027] Regarding the first roller 11 and the first motor M1, please refer to Figure 2 as well as Figure 3 Let's explain further.

[0028] The impression plate 12 is positioned downstream of the first roller 11 on the transport path of the label paper P. The impression plate surface 12a, which is the upper surface of the impression plate 12, is in contact with the backing paper Pa of the label paper P and supports the label paper P from below. Multiple air inlets (not shown) are formed on the impression plate surface 12a. Each air inlet is connected to a suction fan (not shown). By operating the suction fan, air is drawn in through the air inlets, thereby adsorbing the label paper P onto the impression plate surface 12a.

[0029] The print head 8 is positioned opposite the impression plate surface 12a. The print head 8 has rows of nozzles (not shown) corresponding to one or more colors of ink, and ejects ink from the nozzles constituting each row. The print head 8 prints the label Pb by ejecting ink onto the label Pb located on the impression plate surface 12a based on printing data. The label paper P printed by the print head 8 is then conveyed to the downstream peeling section 4 via the first roller 11.

[0030] Although this embodiment describes the case where the label printer 1 prints on the label Pb using an inkjet method, it is not limited to the inkjet method.

[0031] Downstream of the print head 8, a guide member 13 is disposed. The guide member 13 supports the label paper P printed by the print head 8 from below between the impression plate 12 and the peeling section 4. The label paper P is conveyed towards the downstream peeling section 4 by passing above the guide member 13.

[0032] The peeling section 4 includes a peeling member 30 and a second roller 31. The peeling member 30 is located downstream of the guide member 13 of the printing section 3. The peeling member 30 has a guide surface 30a that contacts the backing paper Pa of the label paper P and supports the label paper P from below, and a peeling edge 30b with an acute angle formed at the top of the guide surface 30a. The label paper P, guided by the guide member 13, is conveyed above the guide surface 30a of the peeling member 30.

[0033] The second roller 31 consists of a pair of rollers arranged opposite each other, and conveys the liner paper Pa by clamping it. The second roller 31 is connected to the second motor M2 directly or via gears, belts, etc., and is rotated by the power of the second motor M2.

[0034] The second motor M2 corresponds to an example of the "second drive unit".

[0035] Regarding the second roller 31 and the second motor M2, please refer to Figure 2 as well as Figure 3 Let's explain further.

[0036] When the label printer 1 is operated in peel mode, the user performs the operation of clamping the backing paper Pa of the label paper P with the second roller 31 before printing begins. The second roller 31 is positioned below the peeling member 30 and clamps the backing paper Pa downwards. The backing paper Pa of the label paper P, conveyed on the guide surface 30a, is bent by the peeling edge 30b and pulled downwards by the second roller 31. The tension of the second roller 31 causes the label Pb to float off the backing paper Pa at the peeling edge 30b and be peeled off. The peeled label Pb... Figure 1 The label Pb protrudes to the left from the peeling section 4. The label Pb protruding from the peeling section 4 is collected by the user. On the other hand, the backing paper Pa, which is conveyed by the second roller 31 in a direction different from that of the label Pb, is discharged below the second roller 31.

[0037] In the above structure, the unwinding roller 10, the first roller 11, the impression plate 12, the guide member 13, and the guide surface 30a of the peeling member 30 form a transport path for the label paper P in the printing section 3. Furthermore, the peeling edge 30b and the second roller 31 form part of the transport path for the backing paper Pa.

[0038] The control unit 40 controls the operation of each component constituting the label printer 1. In this embodiment, the control unit 40 controls the driving of the first roller 11 and the second roller 31. That is, the control unit 40 controls the first motor M1 and the second motor M2.

[0039] Regarding control unit 40, please refer to Figure 2 as well as Figure 3 Let's explain further.

[0040] Next, refer to Figure 2 as well as Figure 3 The driving method of the first roller 11 and the driving method of the second roller 31 will be described.

[0041] Figure 2 This is a diagram showing an example of the structure of the main part of label printer 1. Figure 3 The diagram shows an example of the structure of the control unit 40.

[0042] like Figure 2 As shown, the first roller 11 has a first drive roller 11a and a first driven roller 11b that clamp the label paper P. The first motor M1 drives the first drive roller 11a to rotate. The first driven roller 11b is supported in a manner that allows it to rotate along with the label paper P conveyed by the rotation of the first drive roller 11a.

[0043] The second roller 31 has a second drive roller 31a and a second driven roller 31b that clamp the backing paper Pa of the label paper P. The second motor M2 drives the second drive roller 31a to rotate. The second driven roller 31b is supported in a manner that allows it to rotate with the conveying of the backing paper Pa achieved by the rotation of the second drive roller 31a.

[0044] In the first roller 11, in order to hold the label paper P, the first driven roller 11b presses the first drive roller 11a with a force F1. That is, the first drive roller 11a is pressed with a force F1 at the contact point with the label paper P, which is approximately perpendicular to the orientation of the label paper P.

[0045] The surface of the first drive roller 11a is formed by spraying or by applying a powder coating to the surface. In this case, the coefficient of friction μ1 between the first drive roller 11a and the label paper P becomes a sufficiently large value so that the label paper P does not slip relative to the surface of the first drive roller 11a. The surface of the first driven roller 11b is formed of rubber, for example.

[0046] Tension TP is the tension applied to the label paper P between the first roller 11 and the second roller 31. Tension TP satisfies the following equation (1).

[0047] TP<μ1×F1 (1)

[0048] The control unit 40 controls the tension TP by controlling the drive of the first motor M1. For example, the control unit 40 controls the generating torque TE1 produced by the first motor M1 in a manner that makes the tension TP consistent with the target tension value TT.

[0049] In this embodiment, the case where the target tension value TT is a fixed value will be described. In this case, the control unit 40 controls the load torque TL1 applied from the label paper P to the first roller 11 in a manner consistent with the target torque TS corresponding to the target tension value TT. That is, the control unit 40 controls the generating torque TE1 generated by the first motor M1 in a manner that makes the load torque TL1 a target torque TS that is a fixed value.

[0050] In addition, the tension target value TT is set to a value that prevents slack or deflection on the label paper P between the first roller 11 and the second roller 31.

[0051] Regarding the handling of control unit 40, please refer to... Figure 3 Let's explain further.

[0052] In the second roller 31, in order to clamp the liner paper Pa, the second driven roller 31b presses the second drive roller 31a with a force F3. That is, the second drive roller 31a is pressed by the second driven roller 31b with a force F3 at the contact point with the liner paper Pa, which is approximately perpendicular to the direction of travel of the liner paper Pa. The coefficient of friction μ3 is the coefficient of friction between the second drive roller 31a and the liner paper Pa.

[0053] The surface of the second drive roller 31a is formed by spraying or by applying a powder coating to its surface. In this case, the coefficient of friction μ3 between the second drive roller 31a and the liner paper Pa becomes a sufficiently large value so that the liner paper Pa does not slip relative to the surface of the second drive roller 31a. The surface of the second driven roller 31b is, for example, formed of rubber.

[0054] Tension TP is the tension applied to the backing paper Pa between the first roller 11 and the second roller 31. Tension TP satisfies the following equation (2).

[0055] TP<μ3×F3 (2)

[0056] The control unit 40 controls the drive of the second motor M2 in such a way that the conveying speed VP of the liner paper Pa is consistent with the target conveying speed VT. The target conveying speed VT varies in a roughly trapezoidal shape, for example, and the target conveying speed VT corresponding to the rotation angle φ of the second drive roller 31a is stored in a table.

[0057] For example, the target conveying speed VT is set to zero during the period when the print head 8 prints the label paper P, and during the period from when the label Pb reaches the peeling position PP where the label Pb protrudes from the peeling section 4 until the label Pb is recycled by the user.

[0058] Furthermore, after printing the label paper P, a target conveying speed VT is set by accelerating at a fixed acceleration, maintaining a fixed speed, and then decelerating at a fixed acceleration. As a result, the drive of the second motor M2 is controlled to accelerate at a fixed acceleration, maintain a fixed speed, and then decelerate at a fixed acceleration, thereby conveying the label Pb to the peeling position PP.

[0059] The target conveying speed VT corresponds to the "predetermined speed".

[0060] Next, refer to Figure 3 The structure of the control unit 40 will now be explained.

[0061] like Figure 3 As shown, in the control unit 40, the rotation angle θ of the first drive roller 11a is input from the first rotary encoder 11c, and the rotation angle φ of the second drive roller 31a is input from the second rotary encoder 31c.

[0062] The first rotary encoder 11c is disposed, for example, at the end of the first drive roller 11a in the width direction, and detects the rotation angle θ of the first drive roller 11a. The first rotary encoder 11c outputs a detection signal representing the rotation angle θ to the control unit 40.

[0063] Although this embodiment describes the case where the first rotary encoder 11c is disposed on the first drive roller 11a, it is not limited thereto. The first rotary encoder 11c may also be disposed on the first motor M1 and detect the rotation angle of the drive shaft of the first motor M1.

[0064] The second rotary encoder 31c is, for example, disposed at the end of the second drive roller 31a in the width direction, and detects the rotation angle φ of the second drive roller 31a. The second rotary encoder 31c outputs a detection signal representing the rotation angle φ to the control unit 40.

[0065] Although this embodiment describes the case where the second rotary encoder 31c is configured on the second drive roller 31a, it is not limited to this. The second rotary encoder 31c may also be configured on the second motor M2 and detect the rotation angle of the drive shaft of the second motor M2.

[0066] The control unit 40 controls the first voltage V1 applied to the first motor M1. Furthermore, the control unit 40 controls the second voltage V2 applied to the second motor M2.

[0067] Furthermore, although this embodiment describes the control unit 40 controlling the first voltage V1 and the second voltage V2, it is not limited to this. The control unit 40 may also control the first voltage V1 and the second voltage V2 via a voltage control circuit.

[0068] The control unit 40 includes a processor 40A and a memory 40B.

[0069] Memory 40B is a storage device that non-volatilely stores programs or data executed by processor 40A. Memory 40B is composed of semiconductor storage elements such as magnetic storage devices, flash ROM (Read Only Memory), or other types of non-volatile storage devices. Furthermore, memory 40B may also include RAM (Random Access Memory) that constitutes the working area of ​​processor 40A. Additionally, memory 40B may also include non-volatile storage devices such as HDD (Hard Disk Drive) and SSD (Solid State Drive).

[0070] The memory 40B stores the data processed by the control unit 40 or the control program 43 executed by the processor 40A.

[0071] The processor 40A can consist of a single processor or be configured with multiple processors functioning as the processor 40A.

[0072] The control unit 40 can be constructed, for example, using integrated circuits. Integrated circuits include LSIs, ASICs (Application-Specific Integrated Circuits), and PLDs (Programmable Logic Devices). PLDs may include, for example, FPGAs (Field-Programmable Gate Arrays). Furthermore, analog circuitry can be included as part of the integrated circuit structure, or it can be a combination of a processor and an integrated circuit. Combinations of processors and integrated circuits are referred to as microcontrollers (MCUs), SoCs (System-on-a-chip), system LSIs, chipsets, etc.

[0073] The control unit 40 functionally includes a first motor control unit 41 and a second motor control unit 42. Specifically, the processor 40A reads and executes the control program 43 stored in the memory 40B, thereby functioning as both the first motor control unit 41 and the second motor control unit 42.

[0074] The first motor control unit 41 adjusts the first voltage V1 applied to the first motor M1 in a manner that makes the load torque TL1 of the first motor M1 the target torque TS, based on information related to the conveying speed and conveying acceleration of the label paper P.

[0075] The target torque TS corresponds to an example of a "predetermined value".

[0076] Information related to the conveying speed and conveying acceleration of the label paper P includes, for example, the angular velocity ω1 and angular acceleration α1 of the first roller 11 during rotation.

[0077] The angular velocity ω1 can be represented by the following equation (3).

[0078] ω1=dθ / dt (3)

[0079] That is, the angular velocity ω1 is obtained by differentiating the rotation angle θ with respect to time t.

[0080] The angular acceleration α1 can be represented by the following equation (4).

[0081] α1=d 2 θ / dt 2 (4)

[0082] That is, the angular acceleration α1 is obtained by differentiating the rotation angle θ twice with respect to time t. In other words, the angular acceleration α1 is obtained by differentiating the angular velocity ω1 with respect to time t.

[0083] Furthermore, for convenience, the following explanation will focus on the case where the rotational speed of the first motor M1 is the same as the rotational speed of the first roller 11. That is, the explanation will focus on the case where the reduction ratio is "1". Additionally, the explanation will focus on the case where the first motor M1 is a DC motor.

[0084] The relationship between the first voltage V1(t) applied to the first motor M1 and the current I1(t) flowing in the first motor M1 can be expressed by the following equation (5).

[0085] Mathematical formula 1:

[0086]

[0087] Here, constant R1 represents the resistance value of the first motor M1, constant L1 represents the inductance of the first motor M1, and constant K1 represents the torque constant, i.e., the back electromotive force constant, of the first motor M1.

[0088] Since the time required for the current I1 to reach its steady-state value is much shorter than the time required for the angular velocity ω1 (=dθ1 / dt) to reach its steady-state value, in this embodiment, the term representing the time change of the current I1(t), that is, the second term on the right side of equation (5), is set to zero. As a result, equation (6) can be obtained.

[0089] V1(t)=R1×I1(t)+K1×ω1 (6)

[0090] The generating torque TE1 produced by the first motor M1 can be obtained by the following formula (7).

[0091] TE1=K1×I1(t) (7)

[0092] The equation of motion for the first motor M1 can be expressed by the following equation (8).

[0093] TM1=J1×α1+C1×ω1 (8)

[0094] Here, load torque TM1 represents the load torque of the first motor M1, constant J1 represents the moment of inertia of the first motor M1, and constant C1 represents the viscous load of the first motor M1.

[0095] The generating torque TE1 produced by the first motor M1 can be obtained by using the load torque TM1 of the first motor M1 and by the following formula (9).

[0096] TE1 = TM1 + TL1 (9)

[0097] Here, load torque TL1 represents the load torque applied from the label paper P to the first motor M1.

[0098] Using equation (6), the current I1(t) in equation (7) is eliminated. The equation obtained after eliminating the current I1(t) in equation (7) and equation (8) are substituted into equation (9). When solving for the first voltage V1(t), the following equation (10) can be obtained.

[0099] Mathematical formula 2:

[0100]

[0101] The first motor control unit 41 adjusts the first voltage V1 applied to the first motor M1 to the first voltage V1 obtained in equation (10) in such a way that the load torque TL1 of the first motor M1 becomes a predetermined value.

[0102] In this embodiment, the first motor control unit 41 controls the load torque TL1 to match the target torque TS, which is a fixed value. That is, the first motor control unit 41 adjusts the first voltage V1 applied to the first motor M1 to the first voltage V1 obtained in equation (10) so that the load torque TL1 matches the target torque TS, which is a fixed value. By controlling the first voltage V1 applied to the first motor M1 in this way, the tension TP is controlled to match the target tension value TT.

[0103] In other words, the first motor control unit 41 can control the first voltage V1 applied to the first motor M1 by using the first voltage V1 applied to the first motor M1 based on the angular velocity ω1 and angular acceleration α1 of the first roller 11 in rotation and using Equation (10), thereby controlling the tension TP to be consistent with the tension target value TT.

[0104] The second motor control unit 42 performs feedback control on the second voltage V2 applied to the second motor M2 in a manner that makes the conveying speed VP of the liner paper Pa a predetermined speed, based on information related to the rotation angle φ of the second drive roller 31a and the conveying speed VP of the liner paper Pa. The information related to the conveying speed VP of the liner paper Pa is the angular velocity ω2 of the second roller 31 during rotation. The relationship between the conveying speed VP of the liner paper Pa and the angular velocity ω2 of the second roller 31 during rotation can be expressed by the following equation (11).

[0105] VP=R2×ω2 (11)

[0106] Here, the constant R2 represents the radius of the second roller 31.

[0107] On the other hand, in the same manner as equation (6) above, we can obtain equation (12).

[0108] V2(t)=R2×I2(t)+K2×ω2 (12)

[0109] Here, constant R2 represents the resistance value of the second motor M2, and constant K2 represents the torque constant, i.e., the back electromotive force constant, of the second motor M2.

[0110] Furthermore, the generating torque TE2 produced by the second motor M2 can be expressed by the following formula (13).

[0111] TE2=K2×I2(t) (13)

[0112] For example, when the generating torque TE2 produced by the second motor M2 is a fixed value, when the current I1(t) flowing in the first motor M1 in equation (12) is eliminated by using equation (13), the following equation (14) can be obtained.

[0113] V2(t)=R2×TE2 / K2+K2×ω2 (14)

[0114] That is, to increase the angular velocity ω2 of the second roller 31 during rotation, it is only necessary to increase the second voltage V2 applied to the second motor M2. Conversely, to decrease the angular velocity ω2 of the second roller 31 during rotation, it is only necessary to decrease the second voltage V2 applied to the second motor M2. In other words, the second voltage V2 can be used as a control variable to control the conveying speed VP.

[0115] The second motor control unit 42 calculates the angular velocity ω2 of the second roller 31 based on the rotation angle φ of the second roller 31, and calculates the measured value VQ of the conveying speed VP using equation (11). Furthermore, it calculates the difference ΔV between the target conveying speed VT corresponding to the rotation angle φ of the second roller 31 and the measured value VQ of the conveying speed VP, and performs feedback control, for example, PID control, on the second voltage V2 applied to the second motor M2 as a control variable in a manner that makes the difference ΔV zero.

[0116] By adopting this method, the second motor control unit 42 controls the conveying speed VP to the target conveying speed VT.

[0117] Next, refer to Figure 4 Here is a specific example of the operation of the first motor control unit 41. Figure 4 Here is a graph representing an example of the angular velocity ω1 of the first motor M1, the first voltage V1, and the load torque TL1. Figure 4 The simulation results of the angular velocity ω1, the first voltage V1, and the load torque TL1 of the first motor M1 are shown.

[0118] exist Figure 4 The upper part shows the curve of angular velocity ω1. Figure 4 The middle section shows a graph of the first voltage V1. Figure 4 The lower half shows a graph of the load torque TL1.

[0119] exist Figure 4 In the curve graph shown in the upper part, the vertical axis represents the angular velocity ω1, and the horizontal axis represents the time t.

[0120] Curve G1 represents the change in angular velocity ω1. Figure 4In this example, we will explain the variation of angular velocity ω1, as shown in graph G1, for example, in the form of a waveform obtained by half-wave rectification of a sinusoidal current. For instance, during the period from 0 to 0.025 seconds, angular velocity ω1 accelerates from 0 to 1900 rpm. Furthermore, during the period from 0.025 seconds to 0.05 seconds, angular velocity ω1 decelerates from 1900 rpm to 0 rpm. During the period from 0.05 seconds to 0.1 seconds, angular velocity ω1 remains at 0.

[0121] exist Figure 4 In the curve graph shown in the middle part, the vertical axis represents the first voltage V1, and the horizontal axis represents time t. Curve G2 represents the change of the first voltage V1. In addition, the first voltage V1 is controlled by the first motor control unit 41 and based on the above formula (10).

[0122] As shown in graph G2, the first voltage V1 is maintained at -12V during the period when the angular velocity ω1 is kept at 0, for example, during the period from 0.05 seconds to 0.1 seconds. That is, during this period, the first motor M1 drives the first roller 11 in the negative direction. The negative direction refers to the direction in which the roll of paper R is driven in the opposite direction to the direction of travel.

[0123] During the period from 0 seconds to 0.018 seconds, the first voltage V1 increases from -12V to 1.22V. Furthermore, during the period from 0.018 seconds to 0.043 seconds, the first voltage V1 decreases from 1.22V to -15.53V. Additionally, during the period from 0.043 seconds to 0.05 seconds, the first voltage V1 increases from -15.53V to -12V. That is, when the first motor M1 is accelerated, the first voltage V1 increases due to the rotational inertia and viscous load of the first motor M1. When the first motor M1 is decelerated, the first voltage V1 decreases due to the rotational inertia of the first motor M1, and increases due to the viscous load of the first motor M1.

[0124] exist Figure 4 The lower half of the graph shows the curve, where the vertical axis represents the load torque TL1 and the horizontal axis represents time t.

[0125] In curve G3, the load torque TL1 is kept at a roughly fixed value, i.e., -0.02 Nm. A negative load torque TL1 indicates that the first motor M1 is subjected to a load in the direction of travel of the label paper P due to the tension TP applied to the label paper P between the first roller 11 and the second roller 31.

[0126] For reference Figure 4As explained, when the first voltage V1 is controlled by the first motor control unit 41 based on the above formula (10) to change the angular velocity ω1 of the first motor M1, the load torque TL1 can be kept at a roughly fixed value.

[0127] Next, refer to Figure 5 as well as Figure 6 The processing of the control unit 40 will be explained. Figure 5 Here is a flowchart illustrating an example of the control of the first motor M1 implemented by the first motor control unit 41.

[0128] In addition, Figure 5 In this section, we will explain the case where the load torque TL1 is preset to a target torque TS as a fixed value, with the tension TP being the target tension value TT.

[0129] like Figure 5 As shown, firstly, in step S101, the first motor control unit 41 obtains the rotation angle θ of the first drive roller 11a from the first rotary encoder 11c.

[0130] Next, in step S103, the first motor control unit 41 calculates the angular velocity ω1 of the first drive roller 11a by differentiating the rotation angle θ with time t.

[0131] Next, in step S105, the first motor control unit 41 calculates the angular acceleration α1 of the first drive roller 11a by differentiating the angular velocity ω1 with time t.

[0132] Next, in step S107, the first motor control unit 41 calculates the first voltage V1 by substituting the load torque TL1, angular velocity ω1 and angular acceleration α1 into the above equation (10).

[0133] Next, in step S109, the first motor control unit 41 adjusts the first voltage V1 applied to the first motor M1 to the calculated first voltage V1. After that, the process returns to step S101.

[0134] Steps S107 and S109 correspond to an example of “first step”.

[0135] By adopting this method, the first motor control unit 41 adjusts the first voltage V1 applied to the first motor M1 to the first voltage V1 calculated using the above formula (10). Therefore, it is possible to control the tension TP in a way that makes the tension target value TT1 consistent.

[0136] Figure 6Here is a flowchart illustrating an example of the control of the second motor M2 implemented by the second motor control unit 42.

[0137] like Figure 6 As shown, firstly, in step S201, the second motor control unit 42 obtains the rotation angle φ of the second drive roller 31a from the second rotary encoder 31c.

[0138] Next, in step S203, the second motor control unit 42 calculates the angular velocity ω2 of the second drive roller 31a by differentiating the rotation angle φ with time t.

[0139] Next, in step S205, the second motor control unit 42 calculates the measured value VQ of the conveying speed VP of the liner paper Pa based on the calculated angular velocity ω2.

[0140] Next, in step S207, the second motor control unit 42 calculates the difference ΔV between the measured value VQ of the calculated conveying speed VP and the target conveying speed VT corresponding to the rotation angle φ.

[0141] Next, in step S209, the second motor control unit 42 performs PID control on the second voltage V2 applied to the second motor M2 as a control variable in a manner that makes the difference ΔV zero. After that, the process returns to step S201.

[0142] Steps S207 and S209 correspond to an example of “second step”.

[0143] By employing this method, the second motor control unit 42 performs PID control on the second voltage V2 applied to the second motor M2 as a control variable, such that the difference ΔV between the measured value VQ of the conveying speed VP and the target conveying speed VT is zero. Therefore, the second motor control unit 42 can control the conveying speed VP to match the target conveying speed VT.

[0144] The above is for reference only. Figures 1-6As explained, the label printer 1 according to this embodiment includes: a print head 8 that prints a label Pb onto a backing paper Pa; a peeling section 4 that peels the label Pb off the backing paper Pa; a first roller 11 disposed upstream of the peeling section 4 on the transport path of the label paper P; a second roller 31 disposed downstream of the peeling section 4 on the transport path of the backing paper Pa; a first motor M1 that drives the first roller 11; a second motor M2 that drives the second roller 31; and a control unit 40 that controls the first motor. The control unit 40 controls M1 and the second motor M2. It includes: a first motor control unit 41, which adjusts the first voltage V1 applied to the first motor M1 to make the load torque TL1 of the first motor M1 a target torque TS based on information related to the conveying speed VP and conveying acceleration of the label paper P; and a second motor control unit 42, which performs feedback control on the second voltage V2 applied to the second motor M2 to make the conveying speed VP of the liner paper Pa a target conveying speed VT based on information related to the conveying speed VP of the liner paper Pa.

[0145] According to this structure, the first motor control unit 41 adjusts the first voltage V1 applied to the first motor M1 to make the load torque TL1 of the first motor M1 the target torque TS based on information related to the conveying speed VP and conveying acceleration of the label paper P. Therefore, the load torque TL1 of the first motor M1 can be controlled to be the target torque TS. Therefore, appropriate control can be performed to make the tension TP between the first roller 11 and the second roller 31 consistent with the target tension value TT.

[0146] Furthermore, the second motor control unit 42 performs feedback control on the second voltage V2 applied to the second motor M2 based on information related to the conveying speed VP of the liner paper Pa, in a manner that makes the conveying speed VP of the liner paper Pa a target conveying speed VT. Therefore, it is possible to appropriately control the conveying speed VP of the liner paper Pa to be a target conveying speed VT.

[0147] Furthermore, in the label printer 1 according to this embodiment, the information related to the conveying speed VP and conveying acceleration of the label paper P is the angular velocity ω1 and angular acceleration α1 of the first roller 11 during rotation.

[0148] According to this structure, the first motor control unit 41 adjusts the first voltage V1 applied to the first motor M1 based on the angular velocity ω1 and angular acceleration α1 of the first roller 11 during rotation. Therefore, it is possible to appropriately control the load torque TL1 of the first motor M1 to be the target torque TS.

[0149] Furthermore, in the label printer 1 according to this embodiment, the information related to the conveying speed PV of the backing paper Pa is the angular velocity ω2 of the second roller 31 during rotation.

[0150] According to this structure, the second motor control unit 42 performs feedback control on the second voltage V2 applied to the second motor M2 based on the angular velocity ω2 of the second roller 31 during rotation. Therefore, it is possible to appropriately control the conveying speed VP of the liner paper Pa to be the target conveying speed VT.

[0151] Furthermore, in the label printer 1 according to this embodiment, the first motor control unit 41 adjusts the first voltage V1 applied to the first motor M1 by means of formula (A) so that the load torque TL1 of the first motor M1 becomes the target torque TS.

[0152] Mathematical formula 3:

[0153]

[0154] Here, V1(t) on the left represents the voltage applied to the first motor M1. In addition, α1 on the right represents the angular acceleration of the first roller 11, ω1 represents the angular velocity of the first roller 11, and TL1 represents the load torque of the first motor M1.

[0155] According to this structure, the first voltage V1 applied to the first motor M1 can be appropriately controlled in such a way that the load torque TL1 of the first motor M1 becomes the target torque TS.

[0156] Furthermore, in the label printer 1 according to this embodiment, the surfaces of the first roller 11 and the second roller 31 are formed by spraying or by applying powder coating to the surface.

[0157] According to this structure, it is possible to suppress the slippage of the label paper P relative to the surface of the first roller 11. In addition, it is possible to suppress the slippage of the backing paper Pa relative to the surface of the second roller 31.

[0158] In the control method of the label printer 1 according to this embodiment, the label printer 1 includes: a print head 8 that prints a label Pb onto a backing paper Pa; a peeling section 4 that peels the label Pb off the backing paper Pa; a first roller 11 that is disposed upstream of the peeling section 4 on the transport path of the label paper P; a second roller 31 that is disposed downstream of the peeling section 4 on the transport path of the backing paper Pa; a first motor M1 that drives the first roller 11; a second motor M2 that drives the second roller 31; and a control unit 40 that controls the first motor M1 and the second motor M2. The control method of the label printer 1 includes: a first step in which the control unit 40 adjusts the first voltage V1 applied to the first motor M1 to make the load torque TL1 of the first motor M1 a target torque TS based on information related to the conveying speed VP and conveying acceleration of the label paper P; and a second step in which the control unit 40 performs feedback control on the second voltage V2 applied to the second motor M2 to make the conveying speed VP of the liner paper Pa a target conveying speed VT based on information related to the conveying speed VP of the liner paper Pa.

[0159] Therefore, the control method of the label printer 1 according to this embodiment achieves the same effect as the label printer 1 according to this embodiment.

[0160] Furthermore, this embodiment is merely one way of representing the present invention, and it can be arbitrarily modified and applied within the scope of the present invention.

[0161] For example, although the case where the first drive unit in this embodiment is a first motor M1 has been described, it is not limited thereto. The first drive unit may also include a voltage control circuit that controls the first voltage V1 supplied to the first motor M1.

[0162] Furthermore, although the second drive unit in this embodiment has been described as the second motor M2, it is not limited thereto. The second drive unit may also include a voltage control circuit that controls the second voltage V2 supplied to the second motor M2.

[0163] Although this embodiment describes the case where the target torque TS is a fixed value, it is not limited to this. For example, the target torque TS can also be determined based on the size of the label paper P.

[0164] also, Figure 3The functional units shown represent parts of the functional structure, and the specific installation method is not particularly limited. That is, it is not necessarily required to install hardware corresponding to each functional unit individually; a structure in which multiple functional units' functions are implemented by executing a program through a single processor can also be used. Furthermore, in the above embodiments, a portion of the function implemented in software can be implemented in hardware, or a portion of the function implemented in software can be implemented in hardware. Moreover, the specific detailed structure of each part of the label printer 1 can be arbitrarily modified without departing from the spirit of the present invention.

[0165] In addition, for example Figure 5 as well as Figure 6 The processing unit in the flowchart is a unit divided according to the main processing content for easy understanding of the processing of the control unit 40. This invention is not limited to the method or name of the processing unit division. It can also be further divided into more processing units according to the processing content. Furthermore, a processing unit can be divided to include more processes. Moreover, the order of processing can be appropriately changed without affecting the main idea.

[0166] Furthermore, the control method for the label printer 1 can be implemented by having the processor 40A of the control unit 40 execute the control program 43 stored in the memory 40B. Moreover, this control program 43 can be pre-recorded in a computer-readable recording medium.

[0167] As a recording medium, magnetic, optical, or semiconductor memory devices can be used. Specifically, examples include floppy disks, HDDs (Hard Disk Drives), CD-ROMs (Compact Disk Read Only Memory), DVDs (Digital Versatile Discs), Blu-ray discs, optical disks, flash memory, and card-type recording media, which can be either portable or stationary.

[0168] Furthermore, the recording medium can also be a non-volatile storage device such as RAM, ROM, or HDD, which is an internal storage device of the label printer 1. Additionally, the control program 43 can be pre-stored in a server device or the like, and then downloaded from the server device to the control unit 40 of the label printer 1, thereby enabling the functional modules of the control unit 40 of the label printer 1.

[0169] Symbol Explanation

[0170] 1…Label printer (printing unit); 3…Printing section; 4…Peeling section; 8…Print head; 10…Unwind roller; 11…First roller; 11a…First drive roller; 11b…First driven roller; 11c…First rotary encoder; 30…Peeling component; 30b…Peeling edge; 31a…Second drive roller; 31b…Second driven roller; 31c…Second rotary encoder; 40…Control unit; 40A…Processor; 40B…Memory; 41…First motor control unit; 42…Second motor control unit; 4 3…Control program; I1…Current; M1…First motor (first drive unit); M2…Second motor (second drive unit); P…Label paper; Pa…Backing paper; Pb…Label; PV…Conveying speed; TE1, TE2…Generated torque; TL1…Load torque; TM1…Load torque; TS…Target torque; TP…Tension; TT…Target tension value; V1…First voltage; V2…Second voltage; VP…Conveying speed; θ, φ…Rotation angle; ω1, ω2…Angular velocity; α1…Angular acceleration.

Claims

1. A printing apparatus comprising: The print head prints on the label paper that is pasted onto the backing paper; A peeling section that peels the label off the backing paper; The first roller is positioned upstream of the peeling section on the label paper's transport path; The second roller is positioned downstream of the peeling section on the conveying path of the liner paper. A first drive unit drives the first roller; The second drive unit drives the second roller; The control unit controls the first drive unit and the second drive unit. The control unit adjusts the voltage applied to the first drive unit to a predetermined value based on information related to the conveying speed and acceleration of the label paper, and performs feedback control on the voltage applied to the second drive unit to a predetermined speed based on information related to the conveying speed of the backing paper.

2. The printing apparatus as claimed in claim 1, wherein, Information related to the conveying speed and acceleration of the label paper includes the angular velocity and angular acceleration of the first roller during rotation.

3. The printing apparatus as claimed in claim 1 or claim 2, wherein, The information related to the conveying speed of the liner paper is the angular velocity of the second roller during rotation.

4. The printing apparatus as claimed in claim 1, wherein, The control unit adjusts the voltage applied to the first drive unit by means of formula (A) to make the load torque of the first drive unit a predetermined value. Equation (A) is: Here, V1(t) on the left represents the voltage applied to the first drive unit, and J1 on the right represents the moment of inertia of the first drive unit, R1 represents the resistance value of the first drive unit, K1 represents the torque constant of the first drive unit, C1 represents the viscous load of the first drive unit, α1 represents the angular acceleration of the first roller, ω1 represents the angular velocity of the first roller, and TL1 represents the load torque of the first drive unit.

5. The printing apparatus as claimed in claim 1, wherein, The surfaces of the first roller and the second roller are formed by spraying or by applying powder coating to the surface.

6. A method for driving and controlling a printing apparatus, the printing apparatus comprising: The print head prints on the label paper that is pasted onto the backing paper; A peeling section that peels the label off the backing paper; The first roller is positioned upstream of the peeling section on the label paper's transport path; The second roller is positioned downstream of the peeling section on the conveying path of the liner paper. A first drive unit drives the first roller; The second drive unit drives the second roller; The control unit controls the first drive unit and the second drive unit. The driving control method for the printing apparatus includes: In the first step, the control unit adjusts the voltage applied to the first drive unit in a manner that makes the load torque of the first drive unit a predetermined value based on information related to the conveying speed and conveying acceleration of the label paper. In the second step, the control unit performs feedback control on the voltage applied to the second drive unit in a manner that makes the conveying speed of the liner paper a predetermined speed, based on information related to the conveying speed of the liner paper.

Images