Printer device

Abstract

To provide a printer device capable of performing printing by reducing a winding curl generated in roll paper.SOLUTION: According to an aspect of the present disclosure, a printer apparatus includes an accommodating unit that accommodates a sheet wound in a roll shape, a conveying unit that pulls out the sheet from the accommodating unit and conveys the sheet, a printing unit that performs printing on the sheet conveyed by the conveying unit, a damper portion that is provided between the accommodating unit and the printing unit and abuts on the sheet from a winding outer surface side to apply an elastic force to the sheet, and a guide portion that is provided to face the damper portion and forms a conveying path of the sheet having a curved surface opposite to a winding curl of the sheet between the guide portion and the damper portion.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] FIELD An embodiment of the present invention relates to a printer device. [Background technology]

[0002] Conventionally, printers that pull paper from a roll of paper and print on the paper are known. For example, in a thermal printer, which is one example of a printer, paper is pulled from the roll by a transport roller such as a platen roller, and printing is performed by a thermal head positioned opposite the platen roller. Some printers also have a cutter mechanism that cuts off the printed portion of the paper.

[0003] However, paper pulled from a paper roll tends to curl due to its tendency to curl, and the smaller the diameter (winding diameter) of the roll paper, the greater the curvature. In the printer described above, when curled paper is transported, the leading edge of the paper may get caught on unevenness or gaps in the transport path, causing a jam.

[0004] However, conventional printers often lack a mechanism for removing curls from roll paper (a curl removal mechanism). While a printer has been proposed that can change between a straightening position and a retracted position by controlling the position of a transport roller that corrects the curl of roll paper according to the roll diameter (number of rolls) of the roll paper, the configuration is complex and there is room for further improvement. Summary of the Invention [Problem to be solved by the invention]

[0005] The problem to be solved by the present invention is to provide a printer device that can perform printing while reducing curling tendency that occurs in roll paper. [Means for solving the problem]

[0006] The printer device of the embodiment includes a storage unit, a transport unit, a printing unit, a damper unit, and a guide unit. The storage unit stores paper wound in a roll. The transport unit pulls out the paper from the storage unit and transports it. The printing unit prints on the paper transported by the transport unit. The damper unit is provided between the storage unit and the printing unit and contacts the outer surface of the roll of the paper to apply an elastic force to the paper. The guide unit is provided opposite the damper unit and forms a transport path for the paper between the damper unit and the guide unit, with a curved surface opposite to the curl of the paper. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view showing an example of the appearance of a printer apparatus according to an embodiment. [Figure 2] FIG. 2 is a diagram illustrating an example of the internal structure of the printer device according to the embodiment. [Figure 3] FIG. 3 is a partial enlarged view of the platen roller and the first guide portion shown in FIG. [Figure 4] FIG. 4 is a diagram illustrating an example of a hardware configuration of a printer apparatus according to an embodiment. [Figure 5] FIG. 5 is a flowchart showing an example of a printing process performed by the printer device of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments will be described in detail with reference to the drawings. However, the present invention is not limited to the embodiments described below.

[0009] 1 is a perspective view showing an example of the appearance of a printer device 1 according to an embodiment. In this embodiment, the printer device 1 is a thermal printer, and is an example of a printer device.

[0010] In the drawings described below, the left-right direction (X direction), front-back direction (Y direction), and up-down direction (Z direction) of the printer device 1 will be described using the mutually perpendicular X-axis, Y-axis, and Z-axis. In the following description, when simply referred to as the X-axis, Y-axis, or Z-axis, it refers to the respective axial direction and includes two opposite directions. Furthermore, when the positive direction of the X-axis is specified, it refers to a direction from the right to the left, when the positive direction of the Y-axis is specified, it refers to a direction from the rear to the front, and when the positive direction of the Z-axis is specified, it refers to a direction from the bottom to the top.

[0011] The printer device 1 includes a lower housing 11, an upper cover 12, and an outlet 13. The lower housing 11 is a box-shaped container with an opening on one side. The lower housing 11 is provided with a connection terminal (not shown) used to connect to an external device such as a host computer that manages the printer device 1, a power terminal (not shown) that supplies power to the printer body, and the like. The upper cover 12 opens and closes the storage section 15. The upper cover 12 is an example of a lid. One end of the upper cover 12 is rotatably supported on the lower housing 11 by an upper cover rotation shaft 14 (see FIG. 2), and the upper cover 12 opens and closes the opening of the lower housing 11 as it rotates. The lower housing 11 and the upper cover 12 together form a housing 10.

[0012] The discharge port 13 is a gap-like opening through which paper is discharged. In FIG. 1, an example in which the discharge port 13 is provided on the top surface of the printer device 1 is shown.

[0013] Next, the internal structure of the printer device 1 will be described with reference to Fig. 2. Fig. 2 is a diagram showing an example of the internal structure of the printer device 1 according to the embodiment. Fig. 2 also shows a schematic cross section of the printer device 1 shown in Fig. 1 in the YZ direction taken along line AA.

[0014] 2, the printer device 1 stores roll paper 30, which is a long piece of paper 31 wound around a roll core 32, inside the housing 10. The printer device 1 performs printing while pulling out the paper 31 from the stored roll paper 30.

[0015] The paper 31 is, for example, thermal paper. The paper 31 may also be thermal label paper. The thermal label paper may be a strip of labels of a predetermined size attached to a strip of backing paper, or it may be strip-shaped labels without a backing paper. In the following, of the surfaces of the paper 31 pulled out from the paper roll 30, the surface located on the outside (outer periphery) of the paper roll 30 will be referred to as the "outer winding surface side," and the other surface located on the inside (inner periphery) of the paper roll 30 will be referred to as the "inner winding surface side."

[0016] The printer device 1 includes a housing 10 therein, which includes a housing portion 15, a platen roller 16, a thermal head 17, a cutter mechanism 18, and a first guide portion 19.

[0017] Storage section 15 is an example of a storage section. Storage section 15 is a space provided inside housing 10 for storing roll paper 30. Storage section 15 stores roll paper 30 inserted inside housing 10.

[0018] The storage unit 15 also has a roll paper rotation unit 151 on the bottom surface that contacts the stored roll paper 30, for rotating the roll paper 30. The roll paper rotation unit 151 is an example of a rotation unit.

[0019] The roll paper rotation unit 151 is formed by rollers, belts, etc. that can rotate the roll paper 30 in the transport direction (the feed direction and backfeed direction described below). The roll paper rotation unit 151 is driven by a drive source (not shown), such as a stepping motor. Note that the storage unit 15 does not necessarily have to be configured with a roll paper rotation unit 151.

[0020] The storage unit 15 is also provided with a sensor unit 152 for detecting the diameter and remaining amount of the roll paper 30, as well as when the roll paper 30 is nearing the end. The sensor unit 152 is an example of a sensor unit. There are no particular restrictions on the form of the sensor unit 152, and it may be realized by, for example, a reflective photosensor.

[0021] In this embodiment, the storage unit 15 does not support the roll core 32 of the paper roll 30, but the so-called throw-in method is used. However, this is not the only possible configuration. For example, the storage unit 15 may be provided with a bearing or the like to support the roll core 32 of the paper roll 30 in a rotatable manner.

[0022] When using the throw-in method, the printer 1 may be provided with a member (hereinafter also referred to as a flapper) for pressing the roll paper 30 stored in the storage section 15 from above against the inner wall of the storage section 15. In this case, one end of the flapper is rotatably attached to the back side of the top cover 12, for example, and the other end is urged toward the bottom of the storage section 15 by a urging member such as a torsion spring.

[0023] The platen roller 16 is an example of a conveying unit. The platen roller 16 is provided, for example, on the rear side of the top cover 12. The platen roller 16 rotates when a driving force is transmitted from a driving source such as a stepping motor (not shown). The platen roller 16 pulls out paper 31 from the roll paper 30 stored in the storage unit 15 and conveys it toward the discharge opening 13.

[0024] The thermal head 17 is an example of a printing unit. The thermal head 17 is installed, for example, on the inner surface of the lower housing 11. The thermal head 17 abuts against the platen roller 16 when the upper cover 12 is closed.

[0025] The thermal head 17 has a structure in which a plurality of heating elements are aligned. The paper 31 is conveyed toward the discharge port 13 while being sandwiched between the thermal head 17 and the platen roller 16. The thermal head 17 prints on the paper 31 sandwiched between the thermal head 17 and the platen roller 16 by heating the heating elements corresponding to the print pattern.

[0026] Hereinafter, the clamping position between the thermal head 17 and the platen roller 16 will also be referred to as the printing position. The transport direction of the paper 31 transported from the roll paper 30 toward the discharge port 13 will also be referred to as the "feed direction." Transporting in the opposite direction to the feed direction will also be referred to as "backfeed," and the transport direction during backfeeding will also be referred to as the backfeed direction. Furthermore, when the terms "upstream" and "downstream" are used in the transport direction, they refer to the "upstream" and "downstream" sides of the transport direction, respectively.

[0027] The cutter mechanism 18 is an example of a cutting unit. The cutter mechanism 18 is installed, for example, on the rear surface side of the upper cover 12. When the upper cover 12 is closed, the cutter mechanism 18 is located between the thermal head 17 (and the platen roller 16) and the discharge port 13.

[0028] The cutter mechanism 18 has a first blade 181 and a second blade 182. One of the first blade 181 and the second blade 182 is a fixed blade and the other is a movable blade. The first blade 181 and the second blade 182 are arranged opposite each other with the conveyance path of the paper 31 in between. The cutter mechanism 18 also has a drive source for driving the movable blade. The cutter mechanism 18 cuts the paper 31 placed between the fixed blade and the movable blade by moving the movable blade toward the fixed blade.

[0029] In this embodiment, the cutter mechanism 18 is configured to be integrally provided in the printer device 1, but the present invention is not limited to this, and the cutter mechanism 18 may be configured to be detachable from the printer device 1.

[0030] The first guide portion 19 is provided, for example, on the rear surface side of the upper cover 12, around the platen roller 16. Specifically, the first guide portion 19 is provided between the platen roller 16 and the cutter mechanism 18, and functions as a guide member for smoothly moving the paper 31 being transported between the platen roller 16 and the cutter mechanism 18. Note that the first guide portion 19 may also be configured to rotatably hold the platen roller 16.

[0031] The printer device 1 rotates the platen roller 16 in the feed direction to pull out paper 31 from the roll paper 30 and performs printing using the thermal head 17. The printer device 1 discharges the printed portion of the roll paper 30 from the discharge port 13 and cuts that portion using the cutter mechanism 18, outputting the print result. The printer device 1 then transports the paper 31 in the backfeed direction to return the leading edge of the paper 31 to the printing position of the thermal head 17, preparing for the next print.

[0032] The printer device 1 also includes a damper unit 20. The damper unit 20 is an example of a damper unit. The damper unit 20 is provided inside the lower housing 11, between the storage unit 15 and the platen roller 16. The damper unit 20 abuts against one side of the paper 31 (the outer surface side of the roll) and applies an elastic force to the paper 31, thereby reducing the tension applied to the paper 31 when it is pulled out by the platen roller 16.

[0033] Specifically, the damper section 20 has a frame section 201 and a rotating roller 202. The frame section 201 is, for example, a plate-like member provided across the width direction (X direction) of the printer device 1. The rotating roller 202 is provided on the upper end side (one end side) of the frame section 201 and is rotatable in the transport direction of the paper 31.

[0034] The lower end (other end) of the frame unit 201 is rotatably fixed to a rotation shaft (hereinafter also referred to as a frame rotation shaft) provided across the width direction (X direction) of the printer device 1. The frame unit 201 is biased in the clockwise direction indicated by arrow A in the figure by a biasing member such as a torsion spring.

[0035] As a result, the rotating roller 202 contacts and presses one side (outer surface side of the roll) of the paper 31 being transported by the platen roller 16, thereby forming a convex area (hereinafter also referred to as a buffer area) on the paper 31.

[0036] Furthermore, when tension is applied to the paper 31 due to transport in the feed direction by the platen roller 16, the rotation roller 202 is pressed by the tension generated in the paper 31, causing the frame section 201 to rotate counterclockwise. At this time, the tension generated in the paper 31 is buffered by the buffer area, reducing the effect of this tension on the roll paper 30.

[0037] In this way, the damper section 20 reduces the tension applied to the paper 31 by forming a buffer area between the platen roller 16 and the roll paper 30. This allows for stable transport of the paper 31, thereby improving print quality.

[0038] The rotation range of the frame portion 201 is limited to a range between the rotation position in the biased state shown by the solid line in Fig. 2 and the rotation position shown by the dashed line in Fig. 2. Hereinafter, this rotation position in the biased state will also be referred to as the "biased position."

[0039] Incidentally, paper 31 that is pulled out from roll paper 30 will curl according to its tendency to roll. For example, in the configuration shown in Figure 2, paper 31 will curl inward toward the inside of the roll, as indicated by arrow B. Also, the smaller the diameter (winding diameter) of roll paper 30, the greater the curvature of the curl.

[0040] When curled paper 31 is transported, the leading edge of paper 31 may get caught on unevenness or gaps on the transport path, causing a jam. For example, in the configuration of Figure 2, the leading edge of paper 31 may get caught in the gap between platen roller 16 and first guide part 19, as shown in Figure 3.

[0041] Fig. 3 is a partially enlarged view of the platen roller 16 and first guide portion 19 shown in Fig. 2. As shown in Fig. 3, the first guide portion 19 has a wall surface 191 for guiding the paper 31 in the tangential direction of the platen roller 16 with which the paper 31 comes into contact. In addition, a gap 192 is provided between the platen roller 16 and the wall surface 191 to allow the platen roller 16 to rotate smoothly.

[0042] Immediately after the paper 31 is loaded into the printer 1, the curl of the paper 31 is gentle and the leading edge of the paper 31 is positioned downstream in the transport direction beyond the gap 192, so there is little chance that the leading edge of the paper 31 will get caught in the gap 192. However, as the winding diameter of the roll paper 30 becomes smaller, the curl of the paper 31 becomes stronger, and the likelihood that the leading edge of the paper 31 will get caught in the gap 192 increases.

[0043] For example, if the printed portion of the paper is cut by the cutter mechanism 18 and then the paper is fed back to the printing position of the thermal head 17, the leading edge of the paper 31 needs to be stopped near the gap 192, and therefore the leading edge of the paper 31 may get caught in the gap 192. Here, FIG. 3 shows a state in which the leading edge of the paper 31 has gotten caught in the gap 192.

[0044] To prevent the leading edge of paper 31 from entering gap 192, it is possible to position the leading edge of paper 31 downstream away from gap 192 (for example, at a position facing wall surface 191). However, in this case, the leading edge of paper 31 is moved away from the printing position, resulting in extra space at the leading edge of paper 31 where no printing is performed, which hinders efficient printing.

[0045] Therefore, the printer device 1 of this embodiment is provided with a second guide section 21 to reduce curling that occurs in the paper 31. The second guide section 21 will be described below.

[0046] The second guide section 21 is an example of a guide section. The second guide section 21 is provided, for example, on the rear surface side of the upper cover 12, in a position facing the damper section 20. Between the second guide section 21 and the damper section 20, a conveyance path for the paper 31 is formed, which has a curved surface opposite to the curl of the paper 31.

[0047] Specifically, the second guide section 21 has an upstream contact section 211 and a downstream contact section 212 that contact the other surface (the inner surface of the roll) of the paper 31 at two positions sandwiching the damper section 20 in the biased position. The upstream contact section 211 and the downstream contact section 212 are examples of contact sections, and are guide members such as plate-like members that extend downward from the upper side of the printer device 1.

[0048] The upstream contact portion 211 is provided upstream of the damper portion 20 in the biased position and adjacent to the damper portion 20. The tip of the upstream contact portion 211 extends to a position lower in the height direction of the printer device 1 than the damper portion 20 in the biased position. A rotating roller 2111 that can rotate in the transport direction is provided at the tip of the upstream contact portion 211. The tip of the upstream contact portion 211 may have a curved shape with chamfered corners.

[0049] The downstream contact portion 212 is provided downstream of the damper portion 20 in the biased position and at a position separated from the damper portion 20. The tip of the upstream contact portion 211 extends in the height direction of the printer device 1 to a position that is approximately the same as or higher than the damper portion 20 in the biased position. Specifically, the downstream contact portion 212 is provided at a position and height that does not interfere with the rotational movement of the damper portion 20. A rotating roller 2121 that can rotate in the transport direction is provided at the tip of the downstream contact portion 212. The tip of the downstream contact portion 212 may have a curved shape with chamfered corners.

[0050] Additionally, the second guide section 21, together with the damper section 20, forms a transport path for the paper sheet 31. Specifically, the paper sheet 31 is inserted between the damper section 20 and the second guide section 21, and is transported between the upstream contact section 211, the damper section 20, and the downstream contact section 212.

[0051] Here, the upstream contact portion 211, the damper portion 20, and the downstream contact portion 212 form a curved surface opposite to the curl of the paper sheet 31. Specifically, the upstream contact portion 211 and the downstream contact portion 212 come into contact with the position corresponding to the base of the buffer region (convex region) of the paper sheet 31 formed by the damper portion 20 from the inner surface side of the winding, thereby forming a curved surface in the paper sheet 31 opposite to the curling tendency.

[0052] The paper 31 passing through the damper section 20 and the second guide section 21 is curved (warped) in the direction opposite to the curling tendency in the transport path formed by the damper section 20 and the second guide section 21. In other words, the damper section 20 and the second guide section 21 curve the paper 31 in the direction opposite to the curling tendency, so that the paper 31 can be sent to the thermal head 17 with the curling tendency reduced (or corrected).

[0053] This allows the printer device 1 to reduce the occurrence of jams by reducing the likelihood that the leading edge of the paper 31 will get caught on unevenness or gaps on the transport path. For example, in the configuration shown in Figure 2, the leading edge of the paper 31 can be prevented from getting caught in the gap between the platen roller 16 and the first guide part 19, so the leading edge of the paper 31 can be fed back close to the printing position, enabling efficient printing.

[0054] Next, the hardware configuration of the printer device 1 will be described with reference to Fig. 4. Fig. 4 is a diagram showing an example of the hardware configuration of the printer device 1 according to the embodiment.

[0055] As shown in FIG. 4, the printer device 1 includes a computer configuration including a CPU (Central Processing Unit) 101, a RAM (Random Access Memory) 102, a storage unit 103, and the like.

[0056] The CPU 101 is an example of a processor and control unit, and performs overall control of each unit of the printer device 1. The RAM 102 is a volatile storage medium, and is used as a workspace for the CPU 101. For example, the RAM 102 is used as a storage area for temporarily storing print data to be printed on the paper 31. The print data is data to be printed.

[0057] The storage unit 103 is a non-volatile storage medium such as a ROM (Read Only Memory) or flash memory. The storage unit 103 stores various programs executed by the CPU 101 and setting information. For example, the storage unit 103 stores a program related to the printing process described below. The storage unit 103 also stores setting information that defines the relationship between the diameter of the roll paper 30 and the winding operation described below. As an example, the storage unit 103 stores setting information that associates the diameter of the roll paper 30 with the number of winding operations.

[0058] The program executed by the printer device 1 of this embodiment may be configured to be provided by recording it in an installable or executable file format on a computer-readable recording medium such as a CD-ROM, a flexible disk (FD), a CD-R, or a DVD (Digital Versatile Disk).

[0059] Furthermore, the program executed by the printer device 1 of this embodiment may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. Also, the operating program executed by the printer device 1 of this embodiment may be provided or distributed via a network such as the Internet.

[0060] Furthermore, the CPU 101 is connected to a transport driver 104, a head driver 105, and a cutter driver .

[0061] The transport drive unit 104 drives the roll paper rotation unit 151 and the platen roller 16 to control the transport of the paper 31. Specifically, under the control of the CPU 101, the transport drive unit 104 controls the operation of a drive source (not shown) that drives the roll paper rotation unit 151 and the platen roller 16, thereby transporting the paper 31 in the feed direction and the backfeed direction.

[0062] The roll paper rotating unit 151 and the platen roller 16 may be driven by a common drive source, or may be driven by independent drive sources.

[0063] The head driving unit 105 controls the operation of the thermal head 17 by applying electricity to the thermal head 17. Specifically, under the control of the CPU 101, the head driving unit 105 generates a pulse signal (strobe signal) for driving (generating heat) the thermal head 17. Then, the head driving unit 105 causes the heating elements of the thermal head 17 to generate heat using the generated strobe signal.

[0064] The cutter driving unit 106 drives the cutter mechanism 18 to control the operation of the cutter mechanism 18. Specifically, under the control of the CPU 101, the cutter driving unit 106 cuts the paper 31 by controlling the operation of a drive source (not shown) that drives a movable blade.

[0065] A communication interface (I / F) 107 is also connected to the CPU 101. The communication interface 107 is an interface for communicating with a host device (external device) such as a POS terminal. The communication interface 107 is, for example, an infrared communication such as IrDA, a USB (Universal Serial Bus), a LAN (Local Area Network), RS-232C, Bluetooth (registered trademark), etc. The CPU 101 exchanges various information with the host device via the communication interface 107.

[0066] 2. The sensor device provided in the printer device 1 is not limited to the sensor unit 152. For example, the printer device 1 may be provided with an open / close sensor that detects whether the top cover 12 is open or closed, a temperature sensor that measures the temperature of the thermal head 17, or the like.

[0067] In the printer device 1 configured as described above, for example, the CPU 101 acquires print data transmitted from the host device via the communication interface 107. The acquired print data is temporarily stored in the RAM 102, and an image corresponding to the print data is printed on the paper 31 under the control of the CPU 101. More specifically, the CPU 101 controls the transport driver 104 to transport the paper 31 in the feed direction. The CPU 101 also controls the operation of the head driver 105 based on the print data to print an image corresponding to the print data on the paper 31 being transported in the feed direction. Next, when the paper 31 on which printing has been completed is discharged from the discharge port 13, the CPU 101 stops transport in the feed direction and controls the operation of the cutter driver 106 to cut the portion of the paper 31 on which printing has been performed. The CPU 101 then transports the leading edge of the paper 31 in the backfeed direction to the printing position of the thermal head 17, and waits for the next printing.

[0068] When transporting paper 31 in the backfeed direction, CPU 101 preferably controls roll paper rotation unit 151 to rotate roll paper 30 in the backfeed direction, thereby winding up paper 31. When transporting paper 31 in the feed direction, CPU 101 may control roll paper rotation unit 151 to rotate roll paper 30 in the feed direction, or may stop roll paper rotation unit 151.

[0069] Furthermore, when the reel diameter (remaining amount) of the roll paper 30 detected by the sensor unit 152 falls below a threshold, the CPU 101 executes a plying operation that repeatedly transports the paper in the backfeed direction and the forward direction. The amount of feed in the forward direction and the number of repetitions can be set arbitrarily. For example, the amount of feed in the forward direction may be a fixed value, or the amount of feed may be dynamically changed depending on the print data to be printed next. The number of repetitions may be a fixed value, such as one time, or may be dynamically changed depending on the reel diameter (remaining amount). These settings for the plying operation are stored, for example, in the setting information.

[0070] The transport in the backfeed direction is performed within a range where the leading edge of the paper 31 does not exceed the printing position of the thermal head 17. The timing and number of times the paper 31 is plied is not particularly important. For example, the paper 31 may be plied at the same time as the paper 31 is plied after being cut.

[0071] In this way, when the winding diameter of the paper 31 falls below the threshold, the printer device 1 repeats transport in the backfeed direction and the forward direction, thereby performing an operation of plying the paper 31 in the damper section 20 and the second guide section 21. As a result, even if the curvature of the curl that occurs in the paper 31 increases as the winding diameter decreases, the printer device 1 can reduce (or correct) the curling tendency of the paper 31 through the plying operation. Therefore, the printer device 1 can reduce the occurrence of jams caused by the curling tendency of the paper 31, allowing for efficient printing.

[0072] Next, an example of the printing process performed by the printer device 1 will be described with reference to Fig. 5. Fig. 5 is a flowchart showing an example of the printing process performed by the printer device 1 of the embodiment.

[0073] First, the CPU 101 of the printer device 1 controls the transport drive unit 104 to transport the paper 31 in the feed direction (step S11). Next, the CPU 101 controls the head drive unit 105 to print characters (or images) based on the print data on the paper 31 (step S12). Next, the CPU 101 controls the cutter drive unit 106 to cut off the leading edge of the paper 31 on which printing has been performed (step S13).

[0074] Next, CPU 101 determines whether the diameter of roll paper 30 has fallen below a threshold value based on the detection result of sensor unit 152 (step S14). If the diameter of roll paper 30 is equal to or greater than the threshold value (step S14; No), CPU 101 controls conveyance drive unit 104 to feed paper 31 back to the printing position (step S16).

[0075] On the other hand, if the winding diameter of the roll paper 30 falls below the threshold (step S14; Yes), the CPU 101 controls the transport drive unit 104 to perform a winding operation that transports the paper 31 in the backfeed direction and the forward direction a predetermined number of times (step S15). Then, when the winding operation is completed, the CPU 101 proceeds to step S16 and transports the paper 31 to the printing position.

[0076] Next, CPU 101 determines whether or not to end the printing process (step S17). For example, CPU 101 determines to end the printing process when a pre-specified number of sheets have been printed.

[0077] If it is determined that the printing process should not be ended (step S17; No), CPU 101 returns the process to step S11 to continue printing on paper 31. If it is determined that the printing process should be ended (step S17; Yes), CPU 101 ends this process.

[0078] As described above, the printer device 1 according to this embodiment comprises a storage section 15 that stores paper 31 wound in a roll, a platen roller 16 that pulls out the paper 31 from the storage section 15 and transports it, a thermal head 17 that prints on the transported paper 31, a damper section 20 that is provided between the storage section 15 and the thermal head 17 and abuts against the outer surface of the roll of the paper 31 to apply an elastic force to the paper 31, and a second guide section 21 that is provided opposite the damper section 20 and forms a transport path for the paper 31 between it and the damper section 20, with a curved surface that is opposite to the curl of the paper 31.

[0079] As a result, the printer device 1 can reduce (or correct) any curling that occurs in the paper 31 as the paper passes through the damper section 20 and the second guide section 21, making it possible to print on paper 31 with reduced curling. Furthermore, the printer device 1 can reduce fluctuations in tension applied to the paper 31 using the damper section 20, making it possible to achieve stable transport. Therefore, the printer device 1 can efficiently print on the paper 31 and improve print quality.

[0080] Although the embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, modifications, and combinations can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the inventions and their equivalents as set forth in the claims. [Explanation of symbols]

[0081] 1. Printer device 15 Storage section 151 Roll paper rotating unit 152 Sensor unit 16 Platen roller 17 Thermal head 18 Cutter mechanism 19 First guide section 20 Damper section 201 Frame section 202 Rotating Roller 21 Second guide section 211 Upstream contact part 2111 Rotating roller 212 Downstream contact part 2121 Rotating roller 30 rolls of paper 31 Paper 32 Roll core [Prior art documents] [Patent documents]

[0082] [Patent Document 1] Japanese Patent Publication No. 63-074862

Claims

1. a storage section for storing paper wound in a roll; a conveying unit that draws out the paper from the storage unit and conveys it; a printing unit that prints on the paper transported by the transport unit; a damper section provided between the storage section and the printing section, the damper section contacting the outer surface of the roll of the paper to apply an elastic force to the paper; a guide section that is provided opposite the damper section and forms a conveyance path for the paper between the damper section and the guide section, the conveyance path having a curved surface opposite to the curl of the paper; A printer device comprising:

2. the damper section presses the paper from the outer surface side of the roll to form a convex region on the paper that is curved in the opposite direction to the curl of the paper, the guide portion has a contact portion that contacts the paper from the inside surface side of the roll at a position corresponding to the base of the convex region.

2. The printer device according to claim 1.

3. a sensor unit for detecting a roll diameter of the paper stored in the storage unit; a control unit that controls the operation of the transport unit; Further provided with When the roll diameter of the paper falls below a threshold, the control unit causes the conveying unit to perform a rolling operation a predetermined number of times, which repeats conveying the paper in a first conveying direction toward the printing unit and conveying the paper in a second conveying direction opposite to the first conveying direction.

2. The printer device according to claim 1.

4. a rotating unit that rotates the roll of paper stored in the storage unit in the second transport direction, the control unit controls the operation of the rotation unit when transporting the paper in the second transport direction, thereby rotating the rolled paper in the second transport direction.

4. The printer device according to claim 3.

5. a cutting unit that cuts the portion of the paper that has been printed by the printing unit; the control unit causes the conveying unit to perform the threading operation every time the paper is cut by the cutting unit.

5. The printer device according to claim 3 or 4.

Images