Printing apparatus and method for controlling the printing apparatus

Abstract

To suppress erroneous determination of a near-end state of roll paper R.SOLUTION: A printing device 1 includes: a roll paper storage unit that stores roll paper; a platen roller 65 that transports recording paper pulled out from the roll paper; an optical sensor 75 that outputs different outputs according to a diameter of the roll paper; and a control unit 100 that determines whether the roll paper is in a near-end state, using an output of the optical sensor 75, in which the control unit 100 determines whether or not the roll paper is in the near-end state without using the output detected by the optical sensor 75 when the platen roller 65 is accelerated.SELECTED DRAWING: Figure 14

Description

Technical Field

[0001] The present invention relates to a printing apparatus and a method for controlling the printing apparatus.

Background Art

[0002] As disclosed in Patent Document 1, there is known a printing apparatus including a roll paper storage unit that stores roll paper, a transport roller that transports recording paper drawn from the roll paper, a detection unit that performs different outputs according to the diameter of the roll paper, and a control unit that determines whether or not the roll paper is in a near-end state using the output of the detection unit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the printing apparatus of Patent Document 1, since the position of the roll paper is not stable during the acceleration drive of the transport roller, there is a possibility of erroneously determining whether or not the roll paper is in a near-end state.

Means for Solving the Problems

[0005] The printing apparatus of the present invention includes a roll paper storage unit that stores roll paper, a transport roller that transports recording paper drawn from the roll paper, a detection unit that performs different outputs according to the diameter of the roll paper, and a control unit that determines whether or not the roll paper is in a near-end state using the output of the detection unit. The control unit determines whether or not the roll paper is in a near-end state without using the output detected by the detection unit during the acceleration drive of the transport roller.

[0006] The present invention provides a control method for a printing apparatus comprising: a roll paper storage unit for storing roll paper; a transport roller for transporting recording paper pulled out from the roll paper; a detection unit that outputs different values ​​depending on the diameter of the roll paper; and a control unit that uses the output of the detection unit to determine whether or not the roll paper is in a near-end state. The method involves a printing apparatus that performs the step of determining whether or not the roll paper is in a near-end state without using the output detected by the detection unit when the transport roller is accelerated. [Brief explanation of the drawing]

[0007] [Figure 1] This is a perspective view of a printing device. [Figure 2] This is a perspective view of a printing device showing the opening / closing cover in the open position. [Figure 3] This is a cross-sectional view of a printing device. [Figure 4] This is a perspective view of the first-rotation lever. [Figure 5] This is a perspective view of the second-rotating lever. [Figure 6] This is a cross-sectional view of a printing apparatus showing a state where the space between the light guide tube and the light receiving element is blocked. [Figure 7] This is a cross-sectional view of a printing apparatus showing the state in which the space between the light guide tube and the light receiving element is open. [Figure 8] This is a cross-sectional view showing a state in a printing apparatus installed in the first position where the diameter of the roll paper stored in the roll paper storage section is larger than the third diameter. [Figure 9] This is a cross-sectional view showing a state in a printing apparatus installed in the first orientation, where the diameter of the roll paper stored in the roll paper storage section is smaller than the third diameter and larger than the first diameter. [Figure 10] This is a cross-sectional view showing a state in a printing apparatus installed in a first position, where the diameter of the roll paper stored in the roll paper storage section is smaller than the first diameter. [Figure 11] This is a cross-sectional view showing a state in a printing apparatus installed in the second orientation where the diameter of the roll paper stored in the roll paper storage section is larger than the fourth diameter. [Figure 12]This is a cross-sectional view showing a state in a printing apparatus installed in the second orientation, where the diameter of the roll paper stored in the roll paper storage section is smaller than the fourth diameter and larger than the second diameter. [Figure 13] This is a cross-sectional view showing a state in a printing apparatus installed in the second orientation where the diameter of the roll paper stored in the roll paper storage section is smaller than the second diameter. [Figure 14] This is a control configuration for a printing device. [Figure 15] This figure shows an example of the output of an optical sensor. [Figure 16] This is a magnified view of a portion of Figure 15. [Figure 17] This figure shows an example of a determination voltage, which is the result of determining whether or not the roll of paper is in a near-end state. [Figure 18] This flowchart shows the startup process flow. [Figure 19] This flowchart shows the print processing flow. [Figure 20] This is a flowchart following Figure 19. [Modes for carrying out the invention]

[0008] The printing device and its control method will be described below with reference to the attached drawings. Printing device 1 is used, for example, as a receipt printer. In some drawings, directions using the XYZ Cartesian coordinate system shown in each figure will be used for explanation purposes only and will not limit the following embodiments in any way. The +X direction is an example of the "right direction", the -X direction is an example of the "left direction", the +Y direction is an example of the "backward direction", the -Y direction is an example of the "forward direction", the +Z direction is an example of the "upward direction", and the -Z direction is an example of the "downward direction".

[0009] [Printing device configuration] As shown in FIG. 1, the printing apparatus 1 is formed in a substantially rectangular parallelepiped shape, and a discharge port 3 is provided on the first surface A in the -Y direction. The printed recording paper P is discharged from the discharge port 3 (see FIG. 8). The printing apparatus 1 can be installed in a first posture in which the first surface A faces the -Y direction (see FIG. 8) and a second posture in which the first surface A faces the +Z direction (see FIG. 11).

[0010] In the following description, unless otherwise specified, the directions in the XYZ orthogonal coordinate system mean the directions in the printing apparatus 1 installed in the first posture. Also, the XYZ orthogonal coordinate systems shown in the respective figures represent the directions in the printing apparatus 1 installed in the first posture in FIGS. 1 to 10, and represent the directions in the printing apparatus 1 installed in the second posture in FIGS. 11 to 13.

[0011] The printing apparatus 1 includes an apparatus case 5 and an opening / closing cover 7. The apparatus case 5 constitutes the outer shell of the printing apparatus 1 and is formed in a box shape with the surface in the -Y direction open. Inside the apparatus case 5, a roll paper storage section 15 (see FIG. 2) is provided.

[0012] As shown in FIG. 2, the roll paper storage section 15 stores a roll paper R (see FIG. 8) around which a recording paper P serving as a printing medium is wound. The roll paper R is inserted into the roll paper storage section 15 in a drop-in manner so that the rotation axis direction of the roll paper R is parallel to the X direction. That is, the roll paper storage section 15 does not include a support shaft inserted into the core of the roll paper R, and includes a first placement surface 27 and a second placement surface 29 on which the outer peripheral surface Ra of the roll paper R is placed. The roll paper storage section 15 rotatably supports the roll paper R by placing the outer peripheral surface Ra of the roll paper R on the first placement surface 27 or the second placement surface 29.

[0013] The roll paper storage section 15 can selectively store a roll paper R of the first width and a roll paper R of a second width larger than the first width. The first width is, for example, 58 mm, and the second width is, for example, 80 mm.

[0014] <0When a roll of paper R of the first width is stored in the roll paper storage section 15, two roll paper guides 17 are attached to the roll paper storage section 15 (see Figure 2). When a roll of paper R of the second width is stored in the roll paper storage section 15, the two roll paper guides 17 are removed from the roll paper storage section 15. The two roll paper guides 17 are formed in a plate shape and are attached to the roll paper storage section 15, distributed between the +X end and the -X end. Therefore, the center of the roll paper R in the width direction when the roll paper R of the first width is stored in the roll paper storage section 15 and the center of the roll paper R in the width direction when the roll paper R of the second width is stored in the roll paper storage section 15 are approximately the same.

[0015] The roll paper storage section 15 includes a first side wall 23, a second side wall 25, a first mounting surface 27, a second mounting surface 29, a first recess 31 (see Figure 3), and a second recess 33.

[0016] The first side wall 23 and the second side wall 25 are arranged side by side in the X direction, with the second side wall 25 positioned in the +X direction relative to the first side wall 23. The +Y end of the first side wall 23 is provided with a retractable recess 35 that allows the retraction of the second retractable portion 89 (described later) and a suppression recess 37 that allows the retraction of the second suppression portion 95 (described later) (see Figure 3).

[0017] The two roll paper guides 17 are installed between the first side wall 23 and the second side wall 25. When the two roll paper guides 17 are installed in the roll paper storage section 15 and a roll of paper R of the first width is stored in the roll paper storage section 15, both end faces (not shown) of the roll paper R located between the two roll paper guides 17 slide against the roll paper guides 17. When the two roll paper guides 17 are removed from the roll paper storage section 15 and a roll of paper R of the second width is stored in the roll paper storage section 15, both end faces of the roll paper R located between the first side wall 23 and the second side wall 25 slide against the first side wall 23 and the second side wall 25.

[0018] The first mounting surface 27 and the second mounting surface 29 are provided between the first side wall 23 and the second side wall 25. The first mounting surface 27 is located in the -Z direction in the roll paper storage section 15, and the second mounting surface 29 is located in the +Y direction in the roll paper storage section 15. The wall portion having the first mounting surface 27 is referred to as the first wall portion 41, and the wall portion having the second mounting surface 29 is referred to as the second wall portion 43 (see Figure 10).

[0019] The first mounting surface 27 becomes the bottom of the roll paper storage section 15 when the printing device 1 is set up in the first position, and the outer peripheral surface Ra of the roll paper R is placed on it (see Figure 8). The first mounting surface 27 is inclined toward the first recess 31. That is, the first mounting surface 27 is an inclined surface in which the end in the -Y direction is located in the -Z direction compared to the end in the +Y direction (see Figure 10).

[0020] Furthermore, the first mounting surface 27 is provided with a first retractable opening 51 spaced in the +X direction from the first side wall 23. The first retractable opening 51 is located in the overlapping area of ​​the first mounting surface 27 between the area on which the outer surface Ra of the first width roll paper R is mounted and the area on which the outer surface Ra of the second width roll paper R is mounted. The first retractable part 77, which will be described later, extends and retracts from the first retractable opening 51.

[0021] Of the two roll paper guides 17, the roll paper guide 17 in the -X direction is provided between the first side wall 23 and the first retractable opening 51. Therefore, even when two roll paper guides 17 are installed in the roll paper storage section 15, it is possible to prevent the retraction of the first retractable section 77 from being obstructed by the roll paper guide 17 in the -X direction.

[0022] The second mounting surface 29 becomes the bottom of the roll paper storage section 15 when the printing device 1 is set up in the second position, and the outer surface Ra of the roll paper R is placed on it (see Figure 11). The second mounting surface 29 is formed as a curved surface with a substantially arc shape.

[0023] Furthermore, a second retractable opening 59 is provided on the second mounting surface 29, positioned in the +X direction relative to the first side wall 23. Part of the second retractable opening 59 is provided in the overlapping area of ​​the second mounting surface 29 between the area on which the outer surface Ra of the first width roll paper R is placed and the area on which the outer surface Ra of the second width roll paper R is placed. The second retractable opening 59 is provided in the -Z direction relative to the second recess 33 and is formed in a substantially rectangular shape that is long in the X direction. A second retractable part 89, which will be described later, extends and retracts from the second retractable opening 59.

[0024] The first recess 31 is provided between the first mounting surface 27 and the opening / closing cover 7. The first recess 31 extends in a groove-like manner in the X direction.

[0025] The second recess 33 is located at the part of the second mounting surface 29 that is curved in a roughly arc shape, that is, the part that is at the bottom when the printing device 1 is installed in the second orientation. The second recess 33 extends in a groove-like manner in the X direction.

[0026] The opening / closing cover 7 opens and closes the roll paper storage section 15. The opening / closing cover 7 is mounted on the -Z end of the device case 5 so as to be rotatable around an axis substantially parallel to the X direction. The discharge port 3 is provided between the tip of the opening / closing cover 7, i.e., the +Z end, and the device case 5. The discharge port 3 is formed in a substantially rectangular shape that is long in the X direction. In addition, an open lever 63 is provided at the corner of the first surface A in both the -X and +Z directions (see Figure 1). The user can open the opening / closing cover 7 by operating the open lever 63.

[0027] As shown in Figure 3, the printing apparatus 1 includes a platen roller 65, a thermal head 67, an auto cutter 69, a first rotating lever 71, a second rotating lever 73, and an optical sensor 75 (see Figure 6). The platen roller 65 is an example of a "conveyor roller".

[0028] The platen roller 65 is installed inside the opening / closing cover 7 so that its rotation axis is approximately parallel to the X direction. The platen roller 65 grips the recording paper P between itself and the thermal head 67 and rotates using the transport motor 92 (see Figure 14) as the drive source to pull the recording paper P from the roll paper R stored in the roll paper storage section 15 and transport it toward the discharge port 3. When the printing device 1 is set up in the first position, the recording paper P is pulled out from the +Y direction in the roll paper R (see Figure 8). When the printing device 1 is set up in the second position, the recording paper P is pulled out from the -Y direction in the roll paper R (see Figure 11).

[0029] The thermal head 67 is located inside the apparatus case 5, facing the platen roller 65. The thermal head 67 is equipped with multiple heating elements (not shown) and prints on the recording paper P drawn from the roll paper R.

[0030] The auto cutter 69 is located near the discharge port 3 and, using a cutter motor (not shown) as its driving source, cuts the recording paper P behind the printed portion, in the width direction, i.e., in the X direction. More specifically, the auto cutter 69 cuts the recording paper P leaving approximately the center of the recording paper P in the width direction intact, so that the cut recording paper P remains at the discharge port 3.

[0031] The first rotating lever 71, the second rotating lever 73, and the optical sensor 75 are used to determine the near-end state of the roll paper R. As will be described in detail later, the printing device 1 uses the optical sensor 75 to detect the rotation state of the first rotating lever 71 and the second rotating lever 73, and determines whether or not the roll paper R is in the near-end state based on the output of the detection result. Hereinafter, detecting the rotation state of the first rotating lever 71 and the second rotating lever 73 using the optical sensor 75 will be referred to as "detecting the lever state." The optical sensor 75 will output the detection result immediately after detecting the lever state.

[0032] The first rotating lever 71 is positioned in the -Z direction relative to the roll paper storage section 15. The first rotating lever 71 extends in the Y direction and is rotatable in a seesaw-like manner with approximately the middle of the Y direction as the pivot point. The second rotating lever 73 is positioned in the -X direction relative to the roll paper storage section 15. The second rotating lever 73 extends in the Z direction and is rotatable with its end in the +Z direction as the pivot point. The optical sensor 75 is located outside the roll paper storage section 15 and is positioned in the +Y and -Z directions relative to the roll paper storage section 15 (see Figure 6).

[0033] As shown in Figure 4, the first rotating lever 71 comprises a first retractable portion 77, a first connecting portion 79, a first blocking portion 81, and a first shaft portion 83.

[0034] The first retractable portion 77 constitutes approximately half of the first rotating lever 71 in the -Y direction and is formed in a wedge shape extending in the Y direction. The first retractable portion 77 rotates around the first shaft portion 83, thereby extending and retracting from the first retractable opening 51 provided on the first mounting surface 27. Of the first retractable portion 77, the first retractable surface 85 on which the outer peripheral surface Ra of the roll paper R is placed becomes approximately flush with the first mounting surface 27 when the first retractable portion 77 is retracted into the first mounting surface 27 (see Figure 3). In other words, when the first retractable portion 77 retracts into the first mounting surface 27, it becomes approximately flush with the first mounting surface 27. The first retractable portion 77 may also be described as the "first contact portion" that contacts the outer peripheral surface Ra of the roll paper R.

[0035] The first connecting portion 79 constitutes approximately half of the first rotating lever 71 in the +Y direction and is formed in the shape of a roughly rectangular plate. The first connecting portion 79 connects the first retractable portion 77 and the first blocking portion 81.

[0036] The first blocking portion 81 protrudes in the +Z direction from the -X and +Y ends of the first connecting portion 79 and is formed in a substantially polygonal plate shape. The first blocking portion 81 rotates integrally with the first retractable portion 77 around the first shaft portion 83, thereby blocking (see Figure 6) or opening (see Figure 7) the space between the light guide tube 101 and the light receiving element 99, which will be described later.

[0037] The first shaft portion 83 extends in the X direction, passing through approximately the center of the first rotating lever 71 in the Y direction. The first rotating lever 71 rotates about the first shaft portion 83. The first rotating lever 71 is subjected to a force by a first spring (not shown) in the direction in which the first retractable portion 77 protrudes from the first mounting surface 27, that is, clockwise when viewed from the +X direction.

[0038] As shown in Figure 5, the second rotating lever 73 comprises a second fan section 87, a second retractable section 89, a second blocking section 91, a second shaft section 93, and a second suppression section 95.

[0039] The second fan section 87 is formed in a roughly fan-shaped plate form and is provided approximately parallel to the YZ plane.

[0040] The second retractable portion 89 protrudes in the +X direction from approximately the middle of the second fan portion 87 in the Z direction, i.e., the radial direction of the second fan portion 87. The second retractable portion 89 is formed in a roughly rectangular plate shape and is provided approximately parallel to the XY plane. The second retractable portion 89 retracts and extends from the second retractable opening 59 provided on the second mounting surface 29 by rotating around the second shaft portion 93. The second retractable portion 89 may also be described as the "second contact portion" that contacts the outer peripheral surface Ra of the roll paper R.

[0041] The second blocking portion 91 is provided on the radially outer side of the second fan portion 87. The second blocking portion 91 is formed in a substantially arc-shaped plate and is provided substantially parallel to the YZ plane. The second blocking portion 91 rotates integrally with the second retractable portion 89 around the second shaft portion 93, thereby blocking (see Figure 6) or opening (see Figure 7) the space between the light guide tube 101 and the light receiving element 99, which will be described later.

[0042] The second shaft portion 93 protrudes in the +X direction from the +Z end of the second fan portion 87. The second rotation lever 73 rotates around the second shaft portion 93. The second rotation lever 73 is subjected to force by a second spring (not shown) in the direction that causes the second retractable portion 89 to protrude from the second mounting surface 29, that is, clockwise when viewed from the +X direction.

[0043] The second restraining portion 95 is located between the second shaft portion 93 and the second retractable portion 89, and protrudes from the second fan portion 87 in a substantially cylindrical shape in the +X direction. The second restraining portion 95 rotates integrally with the second retractable portion 89 around the second shaft portion 93, thereby extending and retracting from the second restraining opening 61 provided on the second mounting surface 29.

[0044] As shown in Figures 6 and 7, the optical sensor 75 is a light-transmitting sensor and comprises a light-emitting element 97, a light-receiving element 99, and a light guide tube 101.

[0045] The light-emitting element 97 is positioned in the -Z direction relative to the second side wall 25. The light-emitting element 97 emits detection light in the -X direction toward the light-receiving element 99. The light-receiving element 99 is positioned in the -X direction relative to the light-emitting element 97. The light-receiving element 99 receives the detection light emitted from the light-emitting element 97. The light guide tube 101 is located between the light-emitting element 97 and the light-receiving element 99 and extends in the X direction. The light guide tube 101 guides the detection light emitted from the light-emitting element 97 to the light-receiving element 99.

[0046] The optical sensor 75 outputs a first output if the detection light emitted from the light-emitting element 97 is not received by the light-receiving element 99, that is, if the space between the light guide tube 101 and the light-receiving element 99 is blocked by at least one of the first blocking section 81 and the second blocking section 91. The optical sensor 75 also outputs a second output if the detection light emitted from the light-emitting element 97 is received by the light-receiving element 99, that is, if the space between the light guide tube 101 and the light-receiving element 99 is not blocked by either the first blocking section 81 or the second blocking section 91. The first output indicates that the diameter of the roll paper R is greater than or equal to a predetermined diameter, and the second output indicates that the diameter of the roll paper R is less than a predetermined diameter. If the diameter of the unused roll paper R is, for example, 80 mm, then the predetermined diameter is, for example, 23 mm.

[0047] [Detection of lever state] Referring to Figures 8 to 10, the behavior of the first rotation lever 71 and the second rotation lever 73 as the recording paper P is consumed and the diameter of the roll paper R decreases when the printing device 1 is installed in the first position will be explained. In the following explanation, the first diameter refers to the diameter of the roll paper R that is the threshold for whether or not the first retractable part 77 protrudes from the first mounting surface 27 when the printing device 1 is installed in the first position. The third diameter refers to the diameter of the roll paper R that is the threshold for whether or not the second retractable part 89 protrudes from the second mounting surface 29 when the printing device 1 is installed in the first position. The first diameter is smaller than the third diameter. That is, when the printing device 1 is installed in the first position, the first diameter corresponds to the predetermined diameter described above, and when the diameter of the roll paper R becomes less than the first diameter, the optical sensor 75 outputs a second output.

[0048] As shown in Figure 8, when an unused roll of paper R, i.e., a roll of paper R with a diameter larger than the third diameter, is inserted into the roll paper storage section 15 and the outer surface Ra of the roll of paper R is placed on the first mounting surface 27, the first retractable part 77 is pressed down by the roll of paper R and retracts into the first mounting surface 27, and the second retractable part 89 is pressed down by the roll of paper R and retracts into the second mounting surface 29. As a result, the first blocking part 81 blocks the space between the light guide tube 101 and the light receiving element 99, and the second blocking part 91 blocks the space between the light guide tube 101 and the light receiving element 99. Therefore, the optical sensor 75 outputs a first output.

[0049] As shown in Figure 9, when the recording paper P is consumed to a certain extent and the diameter of the roll paper R becomes larger than the first diameter but smaller than the third diameter, the second retractable part 89 is released from being held down by the roll paper R and protrudes from the second mounting surface 29. On the other hand, the first retractable part 77 remains retracted into the first mounting surface 27, held down by the roll paper R. At this time, the second blocking part 91 opens the space between the light guide tube 101 and the light receiving element 99, but the first blocking part 81 remains blocked between the light guide tube 101 and the light receiving element 99. Therefore, the optical sensor 75 produces the first output.

[0050] As shown in Figure 10, as the recording paper P is further consumed and the diameter of the roll paper R becomes smaller than the first diameter, the first retractable part 77 is released from being held down by the roll paper R and protrudes from the first mounting surface 27. The second retractable part 89 remains protruding from the second mounting surface 29. At this time, the first blocking part 81 opens the space between the light guide tube 101 and the light receiving element 99. The second blocking part 91 also remains open between the light guide tube 101 and the light receiving element 99. Therefore, when the diameter of the roll paper R becomes smaller than the first diameter, the optical sensor 75 outputs a second output. In this way, when the printing device 1 is installed in the first position, as the diameter of the roll paper R decreases, the second retractable part 89 and then the first retractable part 77 protrude in that order.

[0051] When the printing device 1 is set up in the first position, the roll paper R moves in the -Y direction toward the first recess 31 due to the inclination of the first mounting surface 27 as the diameter of the roll paper R decreases. The roll paper R also moves in the -Y direction when the recording paper P is pulled in the -Y and +Z directions by the platen roller 65. When the diameter of the roll paper R becomes smaller than the first diameter, the roll paper R enters the first recess 31 (see Figure 10).

[0052] Furthermore, after the roll paper R moves in the -Y direction and enters the first recess 31, the first retractable portion 77 that protrudes from the first mounting surface 27 is positioned in the +Y direction relative to the roll paper R (see Figure 10). Therefore, the first retractable portion 77 that protrudes from the first mounting surface 27 suppresses the roll paper R from moving in the +Y direction from the first recess 31. This prevents the first retractable portion 77 from retracting again due to being pushed by the roll paper R that has moved in the +Y direction from the first recess 31, and consequently suppresses false detections where the diameter of the roll paper R and the output of the optical sensor 75 are different.

[0053] Referring to Figures 11 to 13, the behavior of the first and second rotation levers 71 and 73 will be explained as the recording paper P is consumed and the diameter of the roll paper R decreases when the printing device 1 is installed in the second position. In the following explanation, the second diameter refers to the diameter of the roll paper R that is the threshold for whether or not the second retractable part 89 protrudes from the second mounting surface 29 when the printing device 1 is installed in the second position. The fourth diameter refers to the diameter of the roll paper R that is the threshold for whether or not the first retractable part 77 protrudes from the first mounting surface 27 when the printing device 1 is installed in the second position. The second diameter is smaller than the fourth diameter. That is, when the printing device 1 is installed in the second position, the second diameter corresponds to the predetermined diameter described above, and when the diameter of the roll paper R becomes less than the second diameter, the optical sensor 75 outputs a second output. The second diameter may be the same value as the first diameter described above, or it may be a different value. Furthermore, the fourth diameter may be the same value as the third diameter mentioned above, or it may be a different value.

[0054] As shown in Figure 11, when an unused roll of paper R, i.e., a roll of paper R with a diameter greater than the fourth diameter, is inserted into the roll paper storage section 15 and the outer surface Ra of the roll of paper R is placed on the second mounting surface 29, the first retractable part 77 is pressed down by the roll of paper R and retracts into the first mounting surface 27, and the second retractable part 89 is pressed down by the roll of paper R and retracts into the second mounting surface 29. As a result, the first blocking part 81 blocks the space between the light guide tube 101 and the light receiving element 99, and the second blocking part 91 blocks the space between the light guide tube 101 and the light receiving element 99. Therefore, the optical sensor 75 outputs a first output.

[0055] As shown in Figure 12, when the recording paper P is consumed to a certain extent and the diameter of the roll paper R becomes larger than the second diameter but smaller than the fourth diameter, the first retractable part 77 is released from being held down by the roll paper R and protrudes from the first mounting surface 27. On the other hand, the second retractable part 89 remains retracted into the second mounting surface 29, held down by the roll paper R. At this time, the first blocking part 81 opens the space between the light guide tube 101 and the light receiving element 99, but the second blocking part 91 remains blocked between the light guide tube 101 and the light receiving element 99. Therefore, the optical sensor 75 produces the first output.

[0056] As shown in Figure 13, as the recording paper P is further consumed and the diameter of the roll paper R becomes smaller than the second diameter, the second retractable part 89 is released from being held down by the roll paper R and protrudes from the second mounting surface 29. The first retractable part 77 remains protruding from the first mounting surface 27. At this time, the second blocking part 91 opens the space between the light guide tube 101 and the light receiving element 99. The first blocking part 81 remains open between the light guide tube 101 and the light receiving element 99. Therefore, when the diameter of the roll paper R becomes smaller than the second diameter, the optical sensor 75 outputs a second output. In this way, when the printing device 1 is installed in the second position, the first retractable part 77 and then the second retractable part 89 protrude in that order as the diameter of the roll paper R decreases.

[0057] When the printing device 1 is installed in the second orientation, a second recess 33 is provided in the -Z direction relative to the roll paper R placed on the second mounting surface 29. When the diameter of the roll paper R becomes smaller than the second diameter, the roll paper R fits into the second recess 33 (see Figure 13).

[0058] The second retractable portion 89 protrudes from the second mounting surface 29 on the side furthest from the platen roller 65 relative to the second recess 33, that is, on the side opposite to the side from which the recording paper P is pulled out relative to the roll paper R that has entered the second recess 33. Therefore, even if the amount of protrusion of the second retractable portion 89 is increased, it is possible to suppress the obstruction of the pulling out of the recording paper P by the protruding second retractable portion 89.

[0059] [Control related to determining the near-end state of roll paper] Referring to Figure 14, the control configuration of the printing device 1 will be described. Note that the determination of the near-end state of the roll paper R is performed in the same way regardless of whether the printing device 1 is in the first or second position. The printing device 1 comprises a control unit 100, an optical sensor 75, a transport motor 92, a platen roller 65, an LED (Light Emitting Diode) 94, and a communication unit 96. The optical sensor 75 is an example of a "detection unit". The LED 94 is an example of a "notification unit".

[0060] The control unit 100 includes a CPU (Central Processing Unit) 110, a ROM (Read Only Memory) 120, and a RAM (Random Access Memory) 130.

[0061] ROM 120 stores firmware 121. Firmware 121 is a control program for the CPU 110 to execute various processes. For example, the CPU 110 executes the startup process (see Figure 18) and the printing process (see Figures 19 and 20) described later, based on this firmware 121. Note that the printing process is an example of a "control method for a printing device".

[0062] The control unit 100 may use a hardware circuit such as an ASIC (Application Specific Integrated Circuit) as the processor instead of the CPU 110. Alternatively, the processor may be configured in which one or more CPUs and hardware circuits such as ASICs work together.

[0063] The RAM 130 has a detection counter 131. The detection counter 131 is a counter used in startup processing and printing processing. The CPU 110 updates the value of the detection counter 131 based on the output of the lever state detected by the optical sensor 75.

[0064] As described above, the optical sensor 75 outputs different values ​​depending on the rotational state of the first rotation lever 71 and the second rotation lever 73. More specifically, in both the first and second postures, the optical sensor 75 outputs a first value when at least one of the first retractable portion 77 of the first rotation lever 71 and the second retractable portion 89 of the second rotation lever 73 is retracted, and outputs a second value when both are protruding.

[0065] The optical sensor 75 periodically detects the lever state at least while the platen roller 65 is in operation. For example, the optical sensor 75 repeatedly detects the lever state every 20ms while the platen roller 65 is in operation. In addition, the optical sensor 75 detects the lever state M times every 20ms (where M is an integer such that M ≥ 2) at least when the printing device 1 is started up and when the platen roller 65 stops running. In this embodiment, the value of M is set to "5". When the value of M is "5", the optical sensor 75 detects the lever state over a period of 100ms when the printing device 1 is started up and when the platen roller 65 stops running. In the following description, it is assumed that the optical sensor 75 repeatedly detects the lever state every 20ms while the printing device 1 is powered on, regardless of whether the platen roller 65 is in operation or not, and outputs a signal each time a signal is detected.

[0066] The transport motor 92 is a drive source that drives the platen roller 65. The platen roller 65 is a transport roller that transports the recording paper P drawn from the roll paper R.

[0067] LED94 indicates whether the roll paper R is in a near-end state. The control unit 100 turns off LED94 while it determines that the roll paper R is not in a near-end state, and turns on LED94 when it determines that the roll paper R is in a near-end state.

[0068] The communication unit 96 communicates with an external device (not shown). For example, the communication unit 96 receives print data from an external device such as a PC (Personal Computer). Based on the received print data, the control unit 100 drives the transport motor 92 and the thermal head 67 to print on the recording paper P.

[0069] With the above configuration, the control unit 100 uses the output of the optical sensor 75 to determine whether the roll paper R is in a near-end state. More specifically, the control unit 100 uses the output of the optical sensor 75 to determine whether the roll paper R is in a near-end state, except when the platen roller 65 is being accelerated. In other words, the control unit 100 determines whether the roll paper R is in a near-end state without using the output detected by the optical sensor 75 when the platen roller 65 is being accelerated. This is because when the platen roller 65 is being accelerated, the roll paper R flaps on the first mounting surface 27 or the second mounting surface 29, making it easy to misdetermine the near-end state. For example, when the printing device 1 is installed in a first position, the first retractable part 77 may protrude even if the roll paper R is greater than or equal to the first diameter, or conversely, the first retractable part 77 may retract even if the roll paper R is less than the first diameter. Therefore, when the platen roller 65 is accelerated, the diameter of the roll paper R and the output of the optical sensor 75 tend to differ, and as a result, the control unit 100 is more likely to misjudge the near-end state. Accordingly, the control unit 100 can suppress misjudgment of the near-end state by invalidating the detection result output from the optical sensor 75 when the platen roller 65 is accelerated.

[0070] In this embodiment, the control unit 100 performs accelerated driving for a certain period of time from the start of driving the platen roller 65 during printing, then performs constant-speed driving, and then decelerates driving. That is, regardless of the received print data, the control unit 100 sets a certain period of time from the start of driving the platen roller 65 as an accelerated driving period, and invalidates the output detected during this accelerated driving period. The start of driving the platen roller 65 refers to the start of driving the transport motor 92. The certain period of time, i.e., the accelerated driving period, is, for example, 500 ms.

[0071] The control unit 100 performs a first printing-time determination control to determine whether the roll paper R is in a near-end state, using the output repeatedly received from the optical sensor 75 after the platen roller 65 has finished accelerating and until the platen roller 65 has finished driving. The first printing-time determination control is an example of the "first determination control". The first printing-time determination control is performed in the printing-time processing described later (see Figures 19 and 20).

[0072] In the first printing determination control, the control unit 100 determines whether a second output has been made N times (where N is an integer such that N ≥ 2) consecutively each time an output is made from the optical sensor 75. If the control unit 100 determines that a second output has been made N times consecutively, it determines that the roll paper R is in a near-end state. If it determines that a second output has not been made N times consecutively, it determines that the roll paper R is not in a near-end state. In this embodiment, the value of N is set to "5".

[0073] Furthermore, the control unit 100 performs a second printing-time determination control to determine whether the roll paper R is in a near-end state, using M outputs (where M is an integer such that M ≥ 2), i.e., 5 outputs, that are output when the platen roller 65 has finished driving. The second printing-time determination control is an example of "second determination control". The second printing-time determination control is also performed in the printing-time processing described later (see Figures 19 and 20).

[0074] In the second printing determination control, the control unit 100 determines whether a second output was generated from the optical sensor 75 all five times. If it determines that a second output was generated all five times, it determines that the roll paper R is in a near-end state. If it determines that a first output was generated even once out of the five times, it determines that the roll paper R is not in a near-end state.

[0075] The first printing judgment control will be explained with specific examples, referring to Figures 15 to 17. Figure 15 is a graph showing the output voltage 141, which is the output of the optical sensor 75, as the outer diameter of the roll paper R decreases from 30 mm to 18 mm. Figure 16 is an enlarged view of a part of Figure 15. Figure 17 is a graph showing the judgment voltage 142, which is the judgment result determined by the control unit 100 as to whether or not the roll paper R is in the near-end state.

[0076] Figure 15 illustrates how the outer dimensions of the roll paper R decrease as the printing device 1 repeatedly receives the same print data from an external device and repeats the printing operation based on the received print data.

[0077] As described above, the control unit 100 determines whether the roll paper R is in a near-end state using the output detected by the optical sensor 75 when the platen roller 65 is not being accelerated. In other words, the control unit 100 disables the output detected by the optical sensor 75 when the platen roller 65 is being accelerated, and determines whether the roll paper R is in a near-end state.

[0078] In Figure 15, the acceleration period of the platen roller 65, that is, the period from the start of driving the platen roller 65 until a certain time has elapsed, is shown by the square wave 150. In Figure 15, the low period of the square wave 150 represents the non-acceleration period of the platen roller 65, and the high period of the square wave 150 represents the acceleration period of the platen roller 65. In other words, the low period of the square wave 150 represents the period when the output is enabled, and the high period of the square wave 150 represents the period when the output is disabled.

[0079] As shown in Figure 16, during the High period of the rectangular wave 150, i.e., the acceleration drive period of the platen roller 65, the position of the roll paper R in the roll paper storage section 15 is unstable, resulting in large variations in the value of the output voltage 141. Therefore, the control unit 100 uses the output voltage 141 output during the Low period of the rectangular wave 150 to determine whether the roll paper R is in a near-end state. The output voltage 141 is determined to be either a first output or a second output, with 2V as the threshold. Specifically, if the output voltage 141 is less than 2V, the control unit 100 determines that a first output has been output, indicating that the diameter of the roll paper R is greater than or equal to a predetermined diameter. If the output voltage is 2V or greater, the control unit 100 determines that a second output has been output, indicating that the diameter of the roll paper R is less than a predetermined diameter.

[0080] Figure 17 shows the determination voltage 142, which is the determination result of whether the control unit 100 is in a near-end state based on the output voltage 141 shown in Figure 16. In other words, Figure 17 shows the determination result of the near-end state when the control unit 100 performs the first printing determination control based on the output of the square wave 150 during the low period in Figure 16.

[0081] The determination voltage 142 indicates that if it is 2V, the roll paper R is not in a near-end state, and if it is 3V, the roll paper R is in a near-end state. Therefore, the graph in Figure 17 shows that the roll paper R is not in a near-end state until its diameter is approximately 22.9 mm, and that it is determined to be in a near-end state when its diameter falls below approximately 22.9 mm. Based on the determination voltage 142 shown in Figure 17, the control unit 100 controls the lighting of the LED 94 by issuing an on command or an off command to the LED 94.

[0082] Referring to the flowchart in Figure 18, the startup process will be explained. The startup process is executed when the power to the printer 1 is turned on.

[0083] In step S01, the printing device 1 determines whether the opening / closing cover 7 is closed or not. If the printing device 1 determines that the opening / closing cover 7 is closed, it proceeds to step S02. If the printing device 1 determines that the opening / closing cover 7 is not closed, it repeats step S01.

[0084] In step S02, the printing device 1 determines whether 500ms has elapsed since the opening / closing cover 7 was closed. If the printing device 1 determines that 500ms has elapsed since the opening / closing cover 7 was closed, it proceeds to step S03. If the printing device 1 determines that 500ms has not elapsed since the opening / closing cover 7 was closed, it repeats step S02.

[0085] In step S03, the printing device 1 detects the lever state five times every 20ms using the optical sensor 75. If the output of the optical sensor 75 is the second output, the printing device 1 increments the detection counter 131.

[0086] In step S04, the printing device 1 determines, based on the detection in step S21, whether or not the second output was performed all five times. That is, the printing device 1 determines whether or not the count value of the detection counter 131 is "5". If the printing device 1 determines that the second output was performed all five times, it proceeds to step S05. If the printing device 1 determines that the first output was performed at least once out of the five times, it proceeds to step S07.

[0087] In step S05, the printing device 1 determines that the roll paper R is in a near-end state.

[0088] In step S06, the printing device 1 indicates that the roll paper R is in the near-end state. In step S06, the printing device 1 lights up the LED 94. After step S06, the printing device 1 proceeds to step S09.

[0089] In step S07, the printing device 1 determines that the roll paper R is not in the near-end state.

[0090] In step S08, the printing device 1 indicates that the roll paper R is not in the near-end state. In step S08, the printing device 1 maintains the off state of the LED 94.

[0091] In step S09, the printer 1 resets the count value of the detection counter 131. After step S09, the printer 1 terminates the startup process.

[0092] In the flowchart of Figure 18, steps S04, S05, and S07 are startup determination controls, which are the same as the second print determination control described above. Hereinafter, the startup determination control, the first print determination control, and the second print determination control will be collectively referred to as "determination controls."

[0093] Furthermore, although not shown in the flowchart of Figure 18, if the printing device 1 starts driving the platen roller 65 before the five outputs in step S03 are completed, it will invalidate the output of S03. In this case, if the output of step S03 is invalidated, the printing device 1 maintains the state before the execution of step S03 as a determination of the near-end state.

[0094] Referring to Figures 19 and 20, the flow of the printing process will be explained. The printing process is the process that is executed when the printing device 1 receives print data and starts the printing operation based on the received print data.

[0095] In step S11 of Figure 19, the printing apparatus 1 starts accelerating the platen roller 65.

[0096] In step S12, the printing device 1 determines whether or not the acceleration drive of the platen roller 65 has finished. In this embodiment, the printing device 1 determines that the acceleration drive of the platen roller 65 has finished when a certain amount of time, i.e., 500 ms, has elapsed since the start of the acceleration drive of the platen roller 65 in step S11. If the printing device 1 determines that the acceleration drive of the platen roller 65 has finished, it proceeds to step S13. If the printing device 1 determines that the acceleration drive of the platen roller 65 has not finished, it repeats step S12.

[0097] In step S13, the printing device 1 detects the lever state using the optical sensor 75. Here, the printing device 1 detects the lever state only once. If the output of the optical sensor 75 is the second output, the printing device 1 increments the detection counter 131.

[0098] In step S14, the printing device 1 determines, based on the detection in the preceding step S13, whether or not the second output has been performed five times consecutively. That is, the printing device 1 determines whether or not the count value of the detection counter 131 is "5". If the printing device 1 determines that the second output has been performed five times consecutively, it proceeds to step S15. If the printing device 1 determines that the second output has not been performed five times consecutively, it proceeds to step S19.

[0099] In step S15, the printing device 1 determines that the roll paper R is in a near-end state.

[0100] In step S16, the printing device 1 indicates that the roll paper R is in the near-end state. In step S16, the printing device 1 lights up the LED 94.

[0101] In step S17, the printing device 1 determines whether the platen roller 65 has finished driving, that is, whether the printing operation has finished. If the printing device 1 determines that the platen roller 65 has finished driving, it proceeds to step S18. If the printing device 1 determines that the platen roller 65 has not finished driving, it repeats step S17.

[0102] In step S18, the printer 1 resets the count value of the detection counter 131. After step S18, the printer 1 terminates the printing process.

[0103] In step S19, the printing device 1 determines that the roll paper R is not in the near-end state.

[0104] In step S20, the printing device 1 notifies that the roll paper R is not in the near-end state. In step S20, the printing device 1 maintains the off state of the LED 94.

[0105] In step S21, the printing device 1 determines whether the platen roller 65 has finished driving, that is, whether the printing operation has finished. If the printing device 1 determines that the platen roller 65 has finished driving, it proceeds to step S22. If the printing device 1 determines that the platen roller 65 has not finished driving, it returns to step S13.

[0106] In step S22, the printing device 1 resets the count value of the detection counter 131.

[0107] In step S23 of Figure 20, the printing device 1 detects the lever state five times every 20ms using the optical sensor 75. When the output of the optical sensor 75 is the second output, the printing device 1 increments the detection counter 131.

[0108] In step S24, the printing device 1 determines, based on the detection in step S23, whether or not the second output was performed all five times. That is, the printing device 1 determines whether or not the count value of the detection counter 131 is "5". If the printing device 1 determines that the second output was performed all five times, it proceeds to step S25. If the printing device 1 determines that the first output was performed at least once out of the five times, it proceeds to step S27.

[0109] In step S25, the printing device 1 determines that the roll paper R is in a near-end state.

[0110] In step S26, the printing device 1 indicates that the roll paper R is in the near-end state. In step S26, the printing device 1 lights up the LED 94. After step S26, the printing device 1 proceeds to step S29.

[0111] In step S27, the printing device 1 determines that the roll paper R is not in the near-end state.

[0112] In step S28, the printing device 1 indicates that the roll paper R is not in the near-end state. In step S28, the printing device 1 maintains the off state of the LED 94.

[0113] In step S29, the printer 1 resets the count value of the detection counter 131. After step S29, the printer 1 terminates the printing process.

[0114] In the flowcharts of Figures 19 and 20, steps S14, S15, and S19 are included in the first print-time determination control described above. Also, steps S24, S25, and S27 are included in the second print-time determination control described above.

[0115] Furthermore, although not shown in the flowcharts of Figures 19 and 20, if the printing device 1 starts driving the platen roller 65 before the five outputs in step S23 are completed, it will invalidate the output of step S23. In other words, if the printing device 1 needs to start printing the next received print data after the printing operation of the print data has finished in the printing process while the process of step S23 is being executed, it will invalidate the output of step S23. In this way, if the output in step S23 is invalidated, the printing device 1 maintains the state before the execution of step S23 as a determination of the near-end state.

[0116] Furthermore, although not shown in the flowcharts of Figures 19 and 20, the printing device 1 will stop the printing process if it determines that the roll paper R is in a real-end state while printing is in progress. The real-end state of the roll paper R refers to the state where there is no more roll paper R left. The real-end state is determined, for example, as follows: When the roll paper R reaches the real-end state, the end of the recording paper P wound around the roll paper R separates from the core of the roll paper R and is transported along the transport path of the recording paper P. The printing device 1 determines that the roll paper R is in a real-end state by detecting that the recording paper P has run out using a detection device (not shown) provided on the transport path.

[0117] As described above, the printing apparatus 1 according to this embodiment determines whether the roll paper R is in a near-end state without using the output of the optical sensor 75 when the platen roller 65 is accelerated. As a result, the printing apparatus 1 can determine whether the roll paper R is in a near-end state using the output of the optical sensor 75 detected when the position of the roll paper R is stable, and thereby can suppress misdetermination of the near-end state.

[0118] Furthermore, in the first printing judgment control, the printing device 1 uses the output repeatedly generated between the end of acceleration drive of the platen roller 65 and the end of drive of the platen roller 65 to determine whether or not the roll paper R is in a near-end state. Therefore, the printing device 1 can quickly determine when the roll paper R is in a near-end state.

[0119] Furthermore, in the first printing judgment control, the printing device 1 determines that the roll paper R is in a near-end state when the second output is performed five times consecutively. Therefore, compared to the case where the printing device 1 determines that the roll paper R is in a near-end state when the second output is performed only once, it can suppress erroneous judgments.

[0120] Furthermore, in the second printing judgment control, the printing device 1 uses the output of five readings detected when the platen roller 65 has finished driving to determine whether or not the roll paper R is in a near-end state. In this way, the printing device 1 uses the output detected by the optical sensor 75 when the position of the roll paper R is stable to determine whether or not the roll paper R is in a near-end state, thus suppressing misjudgment of the near-end state.

[0121] Furthermore, in the second printing judgment control, the printing device 1 determines that the roll paper R is in a near-end state if it determines that the second output has been performed all five times. Therefore, the printing device 1 can suppress erroneous judgments that would occur if the roll paper R were in a near-end state when its diameter was greater than or equal to a predetermined diameter.

[0122] Furthermore, if the printing device 1 starts driving the platen roller 65 before the five outputs required for startup judgment control are completed, it disables the output. Similarly, if the printing device 1 starts driving the platen roller 65 before the five outputs required for the second printing judgment control are completed, it disables the output. In this way, the printing device 1 disables the output detected by the optical sensor 75 when the position of the roll paper R is unstable, thereby suppressing misjudgment of the near-end state of the roll paper R.

[0123] Furthermore, the printing device 1 illuminates the LED 94 when it determines that the roll paper R is in a near-end state, and turns off the LED 94 when it determines that the roll paper R is not in a near-end state. In this way, the printing device 1 can inform the user whether or not the roll paper R is in a near-end state.

[0124] Furthermore, the printing device 1 detects the lever state using an optical sensor 75. However, using an optical sensor 75 in this way makes it easy for the diameter of the roll paper R and the output of the optical sensor 75 to differ, and consequently, for the near-end state of the roll paper R to be misjudged. Nevertheless, the printing device 1 can effectively suppress misjudgments through the judgment control described above.

[0125] Furthermore, the optical sensor 75 outputs different values ​​depending on the diameter of the roll paper R placed on the first mounting surface 27 or the second mounting surface 29 of the roll paper storage section 15. When the roll paper R is placed on the mounting surface in this manner, the roll paper R flutters on the mounting surface when the platen roller 65 is accelerated, so the diameter of the roll paper R and the output of the optical sensor 75 tend to differ, and consequently, the near-end state is easily misjudged. However, the printing apparatus 1 can effectively suppress misjudgments through the judgment control described above.

[0126] Furthermore, the optical sensor 75 outputs different values ​​depending on the movement of the first retractable part 77 of the first rotating lever 71 and the second retractable part 89 of the second rotating lever 73. With this configuration, the printing device 1 can detect whether the diameter of the roll paper R is greater than or equal to a predetermined diameter without any problems, even when the roll paper guide 17 (see Figure 2) is attached to the roll paper storage section 15.

[0127] In addition, the following modifications can be adopted instead of the above-described embodiment. [Example 1] The printing device 1 may be equipped with optical sensors 75 corresponding to the first rotating lever 71 and the second rotating lever 73, respectively. That is, the printing device 1 may be configured to include a first optical sensor that detects the protrusion and retraction of the first retractable part 77 of the first rotating lever 71, and a second optical sensor that detects the protrusion and retraction of the second retractable part 89 of the second rotating lever 73. In this case, the printing device 1 determines that a second output has been made if both the first optical sensor and the second optical sensor produce an output indicating the protruding state of the first retractable part 77 and the second retractable part 89, and determines that a first output has been made otherwise.

[0128] [Differentiation 2] The printing device 1 may also detect the diameter of the roll paper R in the roll paper storage section 15 by utilizing the fact that when the diameter of the roll paper R decreases, the position of the core of the roll paper R moves in the -Z direction. For example, the printing device 1 may be provided with a rotating lever that swings to enter the space of the core of the roll paper R when the diameter of the roll paper R becomes less than or equal to a predetermined diameter. In this case, the "detection unit" only needs to detect the swing of the rotating lever.

[0129] [Difference 3] The printing apparatus 1 may also detect the diameter of the roll paper R in the roll paper storage section 15 by utilizing the fact that when the diameter of the roll paper R decreases, the position of the outer surface Ra of the roll paper R changes. For example, the printing apparatus 1 may be provided with a light-emitting section that irradiates light onto the side surface of the roll paper R and a light-receiving section that receives the light reflected from the side surface of the roll paper R. In this case, the "detection section" may detect the diameter of the roll paper R depending on whether or not the light-receiving section receives reflected light.

[0130] [Differentiation Example 4] The printing device 1 may also have a support shaft inserted into the core of the roll paper R, instead of the paper drop-in method. In this case, the printing device 1 may detect the diameter of the roll paper R by utilizing the fact that the position of the outer surface Ra of the roll paper R changes as the diameter of the roll paper R decreases, similar to the modification 3.

[0131] [Difference 5] The printing device 1 may use a mechanical switch instead of an optical sensor 75 to detect the diameter of the roll paper R. For example, in the modified example 2, the "detection unit" may be a mechanical switch that can be switched on and off by the swinging of a rotating lever.

[0132] [Modification 6] The printing device 1 may perform the second printing determination control not only after determining in the first printing determination control that the roll paper R is not in a near-end state, but also after determining that the roll paper R is in a near-end state. That is, in the flowcharts of Figures 19 and 20, the printing device 1 may proceed to step S23 in Figure 20 after S18.

[0133] [Difference 7] In the startup determination control and the second printing determination control, the printing device 1 may determine whether the roll paper R is in the near-end state each time the lever state is detected, rather than determining whether the roll paper R is in the near-end state after the lever state has been detected five times. In this case, the printing device 1 may determine that the roll paper R is in the near-end state if the second output is given from the optical sensor 75 five times in a row, and determine that the roll paper R is not in the near-end state at the time the first output is given from the optical sensor 75.

[0134] [Differentiation 8] The printing device 1 may not set the acceleration drive period to a fixed time regardless of the print data received from the external device, but rather may set the acceleration drive period to a variable time according to the received print data. For example, the printing device 1 may be configured to determine the acceleration drive period according to the print length of the recording paper P based on the print data.

[0135] [Modification 9] The printing device 1 may determine that the acceleration of the platen roller 65 has ended not by waiting a certain period of time after the start of acceleration of the platen roller 65, but by waiting according to the state of the transport motor 92. For example, the printing device 1 may determine that the acceleration of the platen roller 65 has ended when the torque of the transport motor 92 falls below a certain value and a certain period of time has elapsed, or when the torque of the transport motor 92 drops to a certain value.

[0136] [Example 10] The printing device 1 may indicate that the roll paper R is in a near-end state by turning off the LED 94, rather than by turning on the LED 94. In other words, the printing device 1 may turn on the LED 94 while it has determined that the roll paper R is not in a near-end state, and turn off the LED 94 when it has determined that the roll paper R is in a near-end state.

[0137] [Example 11] The printing device 1 may use a method other than the LED 94 to indicate whether or not the roll paper R is in a near-end state. For example, the "notification unit" may be an audio output unit that provides notification by sound, or a display unit that provides notification by displaying characters or images.

[0138] [Example 12] The optical sensor 75 does not necessarily need to periodically detect the lever state while the platen roller 65 is in motion or while the printing device 1 is powered on; it may repeatedly detect the lever state irregularly.

[0139] [Modified example 13] The printing method of the printing device 1 is not limited to the thermal method; for example, it may be an inkjet method or an electrophotographic method. Also, the roll paper R may be a printing medium other than paper, such as film, wound around it.

[0140] [Example 14] The firmware 121 of the printing apparatus 1 according to the above embodiment may be provided to the customer as a program. Alternatively, a storage medium on which the firmware 121 of the printing apparatus 1 according to the above embodiment is recorded may be provided to the customer. Furthermore, modifications can be made as appropriate without departing from the spirit of the present invention.

[0141] [Note] The following is an addendum regarding the printing equipment, printing system, and printing method. The printing apparatus 1 includes a roll paper storage section 15 for storing the roll paper R, a platen roller 65 for transporting the recording paper P drawn from the roll paper R, an optical sensor 75 that outputs different values ​​depending on the diameter of the roll paper R, and a control unit 100 that uses the output of the optical sensor 75 to determine whether or not the roll paper R is in a near-end state. The control unit 100 determines whether or not the roll paper R is in a near-end state without using the output detected by the optical sensor 75 when the platen roller 65 is accelerated.

[0142] The control method for the printing apparatus 1 includes a roll paper storage section 15 for storing the roll paper R, a platen roller 65 for transporting the recording paper P drawn from the roll paper R, an optical sensor 75 that outputs different values ​​depending on the diameter of the roll paper R, and a control unit 100 that uses the output of the optical sensor 75 to determine whether or not the roll paper R is in a near-end state. The printing apparatus 1 performs the step of determining whether or not the roll paper R is in a near-end state without using the output detected by the optical sensor 75 when the platen roller 65 is accelerated.

[0143] With this configuration, the printing device 1 determines whether the roll paper R is in a near-end state without using the output detected by the optical sensor 75 when the platen roller 65 is accelerated. Therefore, the printing device 1 can suppress misdetermination of the near-end state caused by the instability of the position of the roll paper R when the platen roller 65 is accelerated.

[0144] In the above-described printing apparatus 1, it is preferable that the optical sensor 75 repeatedly outputs an output after the platen roller 65 has finished accelerating and until the platen roller 65 has finished driving, and the control unit 100 uses the repeatedly outputted output to perform a first determination control to determine whether or not the roll paper R is in a near-end state.

[0145] With this configuration, the printing device 1 can quickly make a determination between the end of the accelerated drive of the platen roller 65 and the end of the drive of the platen roller 65.

[0146] In the above-described printing apparatus 1, the optical sensor 75 outputs either a first output indicating that the diameter of the roll paper R is greater than or equal to a predetermined diameter, or a second output indicating that the diameter of the roll paper R is less than a predetermined diameter. In the first determination control, the control unit 100 determines whether the second output has been made N times in a row (where N is an integer such that N ≥ 2) each time an output is made. If it is determined that the second output has been made N times in a row, it is determined that the roll paper R is in a near-end state. If it is determined that the second output has not been made N times in a row, it is preferable to determine that the roll paper R is not in a near-end state.

[0147] With this configuration, the printing device 1 can suppress misdetermination of the near-end state compared to the case where the roll paper R is determined to be in the near-end state only when the second output is performed once.

[0148] In the above-described printing apparatus 1, it is preferable that the optical sensor 75 outputs M times (where M is an integer such that M ≥ 2) when the platen roller 65 finishes driving, and the control unit 100 uses the M outputs to perform a second determination control to determine whether or not the roll paper R is in a near-end state.

[0149] With this configuration, the printing device 1 determines the near-end state of the roll paper R using the output detected when the position of the roll paper R is stable, thereby suppressing misdetermination of the near-end state.

[0150] In the printing apparatus 1 described above, the optical sensor 75 outputs either a first output indicating that the diameter of the roll paper R is greater than or equal to a predetermined diameter, or a second output indicating that the diameter of the roll paper R is less than a predetermined diameter. In the second determination control, the control unit 100 determines whether the second output was made in all M attempts. If it is determined that the second output was made in all M attempts, it is determined that the roll paper R is in a near-end state. If it is determined that the first output was made in at least one of the M attempts, it is preferable to determine that the roll paper R is not in a near-end state.

[0151] With this configuration, the printing device 1 can suppress erroneous judgments that determine a near-end state is occurring when the diameter of the roll paper R is greater than or equal to a predetermined diameter.

[0152] In the above-described printing apparatus 1, it is preferable that the control unit 100 disables the output if it starts driving the platen roller 65 after the platen roller 65 has finished driving but before the M output cycles have finished.

[0153] With this configuration, the printing device 1 disables output if the position of the roll paper R becomes unstable due to the start of driving the platen roller 65, thereby suppressing misjudgment of the near-end state of the roll paper R.

[0154] In the above-described printing apparatus 1, it is preferable to further include an LED 94, and to cause the control unit 100 to notify the LED 94 whether or not the roll paper R is in a near-end state.

[0155] With this configuration, the printing device 1 can inform the user whether or not the roll paper R is in a near-end state.

[0156] In the above-described printing apparatus 1, it is preferable to have an optical sensor 75 that outputs different values ​​depending on the diameter of the roll paper R.

[0157] With this configuration, even when using an optical sensor 75 that is prone to misdetecting the diameter of the roll paper R when the position of the roll paper R is unstable, the printing device 1 can suppress misjudgment of the near-end state of the roll paper R.

[0158] In the printing apparatus 1 described above, the roll paper storage section 15 has a first mounting surface 27 and a second mounting surface 29 on which the outer peripheral surface Ra of the roll paper R is placed, and it is preferable that the optical sensor 75 outputs different values ​​depending on the diameter of the roll paper R placed on the first mounting surface 27 or the second mounting surface 29.

[0159] With this configuration, the printing apparatus 1 can suppress misjudgment of the near-end state of the roll paper R, even in a configuration where the diameter of the roll paper R is easily misdetected due to the roll paper R flapping on the first mounting surface 27 or the second mounting surface 29 when the platen roller 65 is accelerated.

[0160] In the printing apparatus 1 described above, the optical sensor 75 is preferably provided so as to be able to extend and retract on the first mounting surface 27 and the second mounting surface 29, respectively. When the diameter of the roll paper R is greater than or equal to a predetermined diameter, the outer peripheral surface Ra is pressed down by the roll paper R placed on the first mounting surface 27 or the second mounting surface 29 and retracts into the first mounting surface 27 or the second mounting surface 29. When the diameter of the roll paper R is less than the predetermined diameter, the first retractable portion 77 and the second retractable portion 89 are released from being pressed down by the roll paper R and protrude from the first mounting surface 27 or the second mounting surface 29. It is preferable to perform different outputs depending on the retraction of these portions.

[0161] With this configuration, the printing device 1 can suppress misjudgment of the near-end state of the roll paper R, even when a member that restricts the position of the roll paper R in the width direction is used. [Explanation of Symbols]

[0162] 1…Printing device, 15…Roll paper storage section, 27…First mounting surface, 29…Second mounting surface, 65…Platen roller, 75…Optical sensor, 77…First retractable part, 89…Second retractable part, 94…LED, 100…Control unit, P…Recording paper, R…Roll paper, Ra…Outer surface.

Claims

1. A roll paper storage section having a mounting surface on which the outer surface of a roll of paper is placed, and which houses the roll of paper, A transport roller for transporting the recording paper drawn from the aforementioned roll of paper, A detection unit that outputs different values ​​depending on the diameter of the roll paper placed on the mounting surface, both when the transport roller is accelerated and when it is not accelerated. A control unit that determines whether the roll paper is in a near-end state using the output performed by the detection unit at times other than when the transport roller is being accelerated, without using the output performed by the detection unit when the transport roller is being accelerated, A printing apparatus characterized by being equipped with

2. The control unit is The printing apparatus according to claim 1, characterized in that, among the outputs performed other than during the acceleration drive, a first determination control is performed to determine whether or not the roll paper is in a near-end state, using the outputs that are repeatedly performed between the end of the acceleration drive of the transport roller and the end of the drive of the transport roller.

3. The detection unit is The system outputs either a first output indicating that the diameter of the roll paper is greater than or equal to a predetermined diameter, or a second output indicating that the diameter of the roll paper is less than the predetermined diameter. The control unit, The printing apparatus according to claim 2, characterized in that, each time the output is performed, it is determined whether the second output has been performed N times in a row (where N is an integer such that N ≥ 2), and if it is determined that the second output has been performed N times in a row, it is determined that the roll paper is in a near-end state, and if it is determined that the second output has not been performed N times in a row, it is determined that the roll paper is not in a near-end state.

4. The control unit is The printing apparatus according to any one of claims 1 to 3, characterized in that a second determination control is performed to determine whether or not the roll paper is in a near-end state, using the output of M times (where M is an integer such that M ≥ 2) that is performed at the end of the drive of the transport roller, out of the output that is performed at times other than the acceleration drive.

5. The detection unit is The system outputs either a first output indicating that the diameter of the roll paper is greater than or equal to a predetermined diameter, or a second output indicating that the diameter of the roll paper is less than the predetermined diameter. The control unit, The printing apparatus according to claim 4, characterized in that, in the second determination control, it is determined whether the second output was performed in all M cycles, and if it is determined that the second output was performed in all M cycles, it is determined that the roll paper is in a near-end state, and if it is determined that the first output was performed in at least one of the M cycles, it is determined that the roll paper is not in a near-end state.

6. The control unit, The printing apparatus according to claim 4 or 5, characterized in that if the drive of the transport roller is started after the drive of the transport roller has finished but before the M output cycles have finished, the output is disabled.

7. Furthermore, with the addition of a news department, The control unit, The printing apparatus according to any one of claims 1 to 6, characterized in that the notification unit notifies whether or not the roll of paper is in a near-end state.

8. The detection unit is The printing apparatus according to any one of claims 1 to 7, characterized in that it has an optical sensor that performs different outputs depending on the diameter of the roll paper.

9. The detection unit is A printing apparatus according to any one of claims 1 to 8, characterized in that a retractable portion is provided on the mounting surface so as to be able to extend and retract, and when the diameter of the roll paper is equal to or greater than a predetermined diameter, the outer surface is pressed by the roll paper placed on the mounting surface and retracts into the mounting surface, and when the diameter of the roll paper is less than the predetermined diameter, the retractable portion is released from being pressed by the roll paper and protrudes from the mounting surface, and different outputs are performed according to the extension and retraction of the retractable portion.

10. A roll paper storage section having a mounting surface on which the outer surface of the roll paper is placed, and which houses the roll paper, A transport roller for transporting the recording paper drawn from the aforementioned roll of paper, A detection unit that outputs different values ​​depending on the diameter of the roll paper placed on the mounting surface, both when the transport roller is accelerated and when it is not accelerated. A printing apparatus comprising a control unit that determines whether or not the roll paper is in a near-end state using the output of the detection unit, A method for controlling a printing apparatus, characterized in that, without performing the step of determining whether the roll paper is in a near-end state using the output performed by the detection unit when the transport roller is accelerated, the detection unit performs the step of determining whether the roll paper is in a near-end state using the output performed at times other than when the transport roller is accelerated.

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