Printer and program

Abstract

To provide a printer and a program that can shorten a work time and simplify replacing work by automatically determining replacement of a thermal head.SOLUTION: A printer which comprises a thermal head which has a plurality of heaters arrayed in a line further comprises: a measurement part which measures resistance values of the respective heaters; a storage part which stores operational information representing an operational state of the thermal head; a determination part which determines whether the thermal head has been replaced based upon change tendencies of a reference resistance value having been measured by the measurement part in the past and the respective resistance values of the heaters that the measurement part has measured; and an update part which updates the operational information when the determination part determines that the thermal head has been replaced.SELECTED DRAWING: Figure 4

Description

[Technical Field]

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

[0002] Conventionally, printers that print characters and the like on thermal paper using a line thermal head equipped with multiple heating elements along a line that intersects with the paper transport direction are known. The printer applies heat to the thermal paper using the heating elements, causing the thermal layer of the thermal paper to develop color, thereby printing.

[0003] In the above printer, when the thermal head is replaced, information related to the operation of the thermal head (hereinafter also referred to as operation information), such as the length of paper printed using the thermal head (hereinafter also referred to as travel distance), is initialized. Conventionally, a technology has been proposed in which, when the thermal head is replaced, the replacement history of parts stored inside the printer is recorded, and the operation information is initialized based on the recorded replacement history. Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above-mentioned technology for initializing operational information requires recording the replacement history in order to initialize the operational information, which is time-consuming for the worker, and there is also the problem that, for example, if there is a omission in the replacement record, the mileage will not be initialized.

[0005] The problem to be solved by the present invention is to provide a printer and a program that can automatically determine when to replace a thermal head, thereby reducing the time required for the work and simplifying the replacement work. [Means for solving the problem]

[0006] The printer of the embodiment is a printer equipped with a thermal head having a plurality of heaters arranged in a line, and is equipped with: a measurement unit that measures the resistance value of each of the heaters; a memory unit that stores operational information indicating the operational status of the thermal head; a judgment unit that judges whether the thermal head has been replaced based on the trend of change between a reference resistance value previously measured by the measurement unit and the resistance value of each of the heaters measured by the measurement unit; and an update unit that updates the operational information when the judgment unit judges that the thermal head has been replaced. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view showing an example of the appearance of a thermal printer according to the first embodiment. [Figure 2] FIG. 2 is a diagram schematically illustrating an example of the internal configuration of the thermal printer according to the first embodiment. [Figure 3] FIG. 3 is a block diagram showing an example of the hardware configuration of the thermal printer according to the first embodiment. [Figure 4] FIG. 4 is a block diagram showing an example of the functional configuration of the thermal printer according to the first embodiment. [Figure 5] FIG. 5 is a table showing an example of the results of resistance values ​​measured by the thermal printer of the first embodiment. [Figure 6] FIG. 6 is a flowchart showing an example of processing executed by the thermal printer of the first embodiment. [Figure 7] FIG. 7 is a block diagram showing an example of the functional configuration of a thermal printer according to the second embodiment. [Figure 8] FIG. 8 is a graph showing an example of the distribution tendency of the reference resistance value in the thermal printer of the second embodiment. [Figure 9] FIG. 9 is a graph showing an example of a distribution tendency of resistance values ​​measured by the thermal printer of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] (First embodiment) A thermal printer 1 according to an embodiment will now be described with reference to the drawings. FIG. 1 is a perspective view showing an example of the exterior of a thermal printer (hereinafter also referred to as printer) 1. The thermal printer 1 is connected to a host device (not shown in the figure, which in this embodiment is a POS (Point of Sales) terminal) and functions as a receipt printer that receives print data, such as transaction information, from the POS terminal and prints receipts. Note that this is just one example of how the thermal printer 1 can be used, and it may also be used in other fields. Furthermore, the method by which the thermal printer 1 obtains print data is not limited to receiving it from a host device, and other methods are also possible.

[0009] The thermal printer 1 comprises an upper housing 2 and a lower housing 3. The upper housing 2 is rotatably mounted on the lower housing 3 around one end 4 as an axis. When the upper housing 2 is rotated from the state shown in Fig. 1, the interior of the thermal printer 1 is opened. An operation unit 5 is provided on the top surface of the upper housing 2.

[0010] The operation unit 5 has multiple operation buttons 6. The operation unit 5 is used to input various commands to the thermal printer 1, including turning the power on and off. Some of the operation buttons 6 have light-emitting units. The light-emitting units are composed of, for example, LEDs (Light Emitting Diodes). The thermal printer 1 also has an issuing port 7. The issuing port 7 ejects printed receipts 8 from inside the thermal printer 1 to the outside.

[0011] Figure 2 is a diagram showing a schematic diagram of an example of the internal structure of the thermal printer 1. As shown in Figure 2, the thermal printer 1 includes a holding unit 11, a plurality of guide rollers 12, a platen 13, a thermal head 14, a cutter 15 consisting of a pair of blades, and the like.

[0012] The holder 11 rotatably holds the rolled thermal paper 16. The guide rollers 12 guide the thermal paper 16 unwound from the holder 11 between the platen 13 and the thermal head 14. Two pairs of guide rollers 12 are provided in the transport path from the holder 11 to between the platen 13 and the thermal head 14.

[0013] The platen 13, while sandwiching the thermal paper 16 between it and the thermal head 14, rotates using a transport motor as a drive source to transport the thermal paper 16. The transport motor is, for example, a stepping motor. The platen 13 and transport motor together form a transport unit 18 that transports the thermal paper 16.

[0014] The thermal head 14 is a line thermal head in which multiple heating elements (hereinafter also referred to as heaters) are provided on a line along a direction (direction perpendicular to the paper surface in FIG. 2 ) that intersects (orthogonal in this embodiment) the transport direction of the thermal paper 16. The thermal head 14 is urged toward the platen 13 with a predetermined pressure. The thermal head 14 prints on the thermal paper 16 transported by the transport unit 18 by generating heat from the heating elements to apply thermal energy to the thermal paper 16.

[0015] The cutter 15 is formed by combining a fixed blade and a movable blade, both of which are flat and have the same shape, and by sliding the movable blade relative to the fixed blade, it is possible to cut the thermal paper 16 conveyed by the conveying section 18 at any position. In Figure 2, the fixed blade is located at the top and the movable blade is located at the bottom.

[0016] The movable blade is driven by a cutter motor and can move up and down in Figure 2. The movable blade is normally positioned downwards to allow the thermal paper 16 to pass between it and the fixed blade, and then moves upwards when cutting the thermal paper 16. The thermal paper 16 cut by the cutter 15 is issued as a receipt 8 from the issuing port 7.

[0017] Fig. 3 is a diagram showing an example of the hardware configuration of the printer 1 according to this embodiment. As shown in Fig. 3, the printer 1 includes a CPU (Central Processing Unit) 31, a ROM (Read Only Memory) 32, a RAM (Random Access Memory) 33, an I / F (Interface) 34, an auxiliary storage device 35, and the like, which are interconnected via a bus 36.

[0018] The CPU 31 is a calculation device that controls the overall operation of the printer 1. The CPU 31 is an example of a processor in the printer 1 of this embodiment, and another processor or processing circuit may be provided instead of the CPU 31. The ROM 32 stores programs and the like that realize various processes by the CPU 31. The RAM 33 is, for example, a main storage device of the printer 1, and stores data necessary for various processes by the CPU 31.

[0019] The I / F 34 is an interface for transmitting and receiving data. The I / F 34 is also an interface for communicating with a POS terminal, which is a higher-level device. The auxiliary storage device 35 stores various data such as programs executed by the CPU 31. The auxiliary storage device 35 also stores operational information. The auxiliary storage device 35 is configured with a rewritable non-volatile storage medium such as an EEPROM (Electrically Erasable Programmable Read-Only Memory). The auxiliary storage device 35 may also be configured to use a partial area within the ROM 32.

[0020] Here, the operational information will be described. The operational information indicates the operational status of the thermal head 14, for example, the travel distance of the thermal head 14. The travel distance of the thermal head 14 is, for example, a recorded value obtained by counting the number of steps of the conveyance motor that rotates the platen 13 and the number of rotations of the platen 13 when printing with the thermal head 14. The operational information may also include the replacement history (replacement date and time) of the thermal head 14. Note that the recording of the operational information is performed by the CPU 31 or a functional unit realized by the CPU 31.

[0021] Next, we will explain the functional configuration of the printer 1. Figure 4 is a block diagram showing an example of the functional configuration of the printer 1. The printer 1 realizes the following functions as a measurement unit 41, a registration unit 42, a determination unit 43, an update unit 44, and a notification unit 45 by the CPU 31 operating in accordance with a program stored in the ROM 32. Note that each of these functions may also be configured as hardware.

[0022] The measuring unit 41 measures the resistance value of each of the heaters arranged in a line on the thermal head 14. Specifically, the measuring unit 41 measures the resistance value of the heater when the printer 1 is started. There is no particular restriction on the method for measuring the resistance value of the heater, and various methods can be used.

[0023] For example, the measurement unit 41 measures the resistance value of each heater by individually applying a predetermined measurement voltage (and current) to each heater when the printer 1 is started up. Specifically, the measurement unit 41 reads the applied resistance value of each heater via an A / D (Analog-To-Digital) converter and obtains the read resistance value as the measurement result.

[0024] The registration unit 42 stores the resistance value of each heater measured by the measurement unit 41 in the RAM 33 or the like. The registration unit 42 also stores (hereinafter also referred to as registering) the resistance value of each heater measured under predetermined conditions in a non-volatile storage medium such as the auxiliary storage device 35 as a reference resistance value.

[0025] Specifically, the registration unit 42 registers the heater measurement value measured when the printer 1 is first started as the reference resistance value in the auxiliary storage device 35. Here, the first start-up refers to the timing when the printer 1 is started for the first time after its manufacture.

[0026] Furthermore, when the determination unit 43 determines that the thermal head has been replaced, the registration unit 42 registers as the reference resistance value the resistance value measured by the measurement unit 41 at the time the determination unit 43 made the determination. In this manner, in this embodiment, by the registration unit 42 registering the reference resistance value, it is possible to grasp the change in the resistance value of the heater when the thermal head 14 is replaced.

[0027] The determination unit 43 determines whether the thermal head has been replaced based on the tendency of change between the reference resistance value registered by the registration unit 42 and the resistance value of each heater measured by the measurement unit 41.

[0028] Generally, the characteristics of each heater that makes up a thermal head, that is, the tendency of the resistance value of each heater, differ from one thermal head to another. Therefore, by measuring the resistance value of the heaters in a thermal head and comparing the tendency, it is possible to determine whether the thermal head is the same or a different thermal head. In other words, if the tendency of the heater resistance value changes, it can be determined that the thermal head has been replaced.

[0029] When the thermal head 14 is replaced, the printer 1 of this embodiment stores the resistance values ​​of multiple heaters as reference resistance values ​​in the auxiliary storage device 35. The determination unit 43 compares the trend of the stored reference resistance values ​​with the trend of the resistance values ​​of each heater measured by the measurement unit 41, and determines whether the thermal head has been replaced based on the trend of changes in both resistance values.

[0030] Here, the processing executed by the determination unit 43 will be described with reference to FIG. 5. FIG. 5 shows the measurement results of the resistance values ​​of each heater measured by the measurement unit 41 when the printer 1 is started. For ease of explanation, FIG. 5 illustrates the results of multiple measurements taken by the measurement unit 41, but in this embodiment, it is sufficient that the resistance value most recently measured by the measurement unit 41 is stored in RAM 33 or the like. In FIG. 5, the resistance value for measurement number 1 represents the reference resistance value. Also, in FIG. 5, the heater numbers correspond to the positions of the heaters arranged on the thermal head 14 and indicate the arrangement order of the heaters.

[0031] For example, the determination unit 43 determines whether the thermal head 14 has been replaced based on the change trend in the resistance value of each heater, which is obtained by calculating the difference between the resistance value of the same heater (heater number) at measurement number 1 and the resistance value at measurement number 2. In this case, there is no difference in the resistance value of each heater, and the trend in the resistance value has not changed, so the determination unit 43 determines that the thermal head 14 has not been replaced.

[0032] Also, for example, the judgment unit 43 calculates the difference in resistance value corresponding to each heater between the result of measurement 1 and the result of measurement N, and makes a judgment. In this case, the difference in resistance value between each heater is about 20, but the difference value is approximately the same for each heater. This is a result of using the printer 1. In such a case, since the trend in the resistance value of the heaters as a whole has not changed, the judgment unit 43 determines that the thermal head 14 has not been replaced.

[0033] Furthermore, for example, the determination unit 43 determines the difference in resistance value corresponding to each heater between the result of measurement 1 and the result of measurement N+1. In this case, the difference in value for each heater is 12 for heater 1, 10 for heater 2, 8 for heater 3, 6 for heater 4, 4 for heater 5, 2 for heater 6, 0 for heater 7, etc., and there is variation for each heater. Since such variation indicates a change in the trend of the resistance values, the determination unit 43 determines that the thermal head 14 has been replaced.

[0034] In this way, the determination unit 43 checks the change trend of the resistance value of each heater by comparing it with the reference resistance value when the printer 1 is started. Then, the determination unit 43 can automatically determine that the thermal head has been replaced based on the change trend of the resistance value of each heater. Note that, although the determination unit 43 determines the difference between the reference resistance value and the measured resistance value for each heater, the determination method is not limited to this.

[0035] The update unit 44 updates the operational information when the determination unit 43 determines that the thermal head 14 has been replaced. For example, the update unit 44 resets the mileage included in the operational information stored in the auxiliary storage device 35 to 0. Furthermore, for example, the update unit 44 records the date and time when the thermal head 14 was replaced in the operational information in the auxiliary storage device 35 based on the date and time measured by an RTC (Real Time Clock) or the like.

[0036] This reduces the amount of work required and shortens the work time by having the update unit 44 update the operational information of the thermal head 14 when the thermal head 14 is replaced. Furthermore, automatic updating by the update unit 44 prevents the initialization of the operational information from being overlooked, simplifying the work of replacing the thermal head 14.

[0037] When the determination unit 43 determines that the thermal head 14 has been replaced, the notification unit 45 issues a notification that the thermal head 14 has been replaced. Specifically, the notification unit 45 notifies the POS terminal connected to the printer 1 by displaying a message on the display device of the POS terminal to notify that the thermal head 14 has been replaced. Furthermore, when the notification unit 45 determines that the thermal head 14 has been replaced, it turns on a light-emitting unit of the printer 1 to notify that the thermal head 14 has been replaced. However, the content of the notification is not limited to this.

[0038] In this embodiment, the determining unit 43 and the notifying unit 45 are described separately, but these functions may be provided by a single functional unit.

[0039] Next, a description will be given of an example of the operation of the printer 1. Fig. 6 is a flowchart showing an example of processing executed by the printer 1 according to this embodiment. The processing of this flowchart is started, for example, when the printer 1 is started.

[0040] First, the measuring unit 41 measures the resistance value of each heater in the thermal head 14 in the printer 1 (step S1).

[0041] Next, the judgment unit 43 compares the reference resistance value with the resistance value of each heater measured by the measurement unit 41 (step S1), and determines whether the thermal head has been replaced based on the change trend of the resistance value (step S2).

[0042] If the determining unit 43 determines that the thermal head has not been replaced (step S2: No), this process ends.

[0043] On the other hand, if the determining unit 43 determines that the thermal head has been replaced (step S2: Yes), the process proceeds to step S3.

[0044] Next, the registration unit 42 registers the reference resistance value based on the resistance value of the heater measured by the measurement unit 41 (step S3). Furthermore, the update unit 44 updates the operation information (step S4). After the update process is completed, the process proceeds to step S5.

[0045] Next, the notification unit 45 issues a notification that the thermal head 14 has been replaced (step S5). After the notification process is completed, this process ends.

[0046] As described above, in the printer 1 according to this embodiment, the measurement unit 41 measures the resistance value of each heater in the thermal head 14. The determination unit 43 determines whether the thermal head 14 has been replaced based on the trend of change between the reference resistance value and the resistance value of each heater measured by the measurement unit 41. If it is determined that the thermal head 14 has been replaced, the update unit 44 updates the operational information.

[0047] As a result, if it is determined that the thermal head 14 has been replaced, the reference heater resistance value is registered. The printer 1 can determine that the thermal head 14 has been replaced because the reference resistance value has been registered. Furthermore, the printer 1 can update its operational information because the thermal head 14 has been replaced. Furthermore, by updating the operational information, the printer 1 can shorten the work time and simplify the replacement work.

[0048] (Second embodiment) The second embodiment will be described with reference to the drawings.

[0049] Next, a second embodiment will be described. Explanations of parts common to the first embodiment will be omitted where appropriate. Note that the same components as those in the first embodiment will be given the same reference numerals and explanations will be omitted where appropriate.

[0050] In the first embodiment, the resistance values ​​of the heaters are directly compared to determine the change in resistance when the thermal head is replaced. In the second embodiment, the resistance values ​​of the heaters are statistically analyzed to determine the change in resistance when the thermal head is replaced.

[0051] Specifically, the printer 1 according to the second embodiment further includes a calculation unit 46. The calculation unit 46 calculates the distribution tendency of the resistance values ​​of the heaters based on the resistance values ​​measured by the measurement unit 41.

[0052] 7, the calculation unit 46 calculates the distribution tendency of the resistance value of each heater based on the resistance value measured by the measurement unit 41. Here, the distribution tendency of the resistance value calculated by the calculation unit 46 will be described with reference to FIGS.

[0053] FIG. 8 is a graph of the reference resistance values, with the heater number of each heater on the horizontal axis and the resistance value [Ω] on the vertical axis. The calculation unit 46 graphs the resistance values ​​measured by the measurement unit 41 to understand the distribution trend of the resistance values ​​of each heater. For example, the trend of the reference resistance values ​​shown in FIG. 7 is such that graph GR1 has seven peaks and six valleys. Also, graph GR1 has one location where the resistance value tends to fall below line L1, which indicates 700 Ω.

[0054] 9 is a graph of the resistance values ​​measured by the measuring unit 41 at measurement count N+1. The trend of the measured resistance values ​​shown in FIG. 9 is such that, for example, graph GR2 has eight peaks and eight valleys. The trend of the reference values ​​shown in FIG. 9 is such that, for example, graph GR2 has two points where the resistance value falls below line L1, which indicates 700 Ω.

[0055] In this way, by using the distribution tendency of the resistance value of the thermal head calculated by the calculation unit 46, it is possible to easily grasp the tendency of the resistance value of the entire heater that constitutes the thermal head.

[0056] Furthermore, the determination unit 43 determines whether or not the thermal head 14 needs to be replaced based on the distribution trend of the reference resistance values ​​calculated by the calculation unit 46 and the distribution trend of the measured resistance values. For example, when comparing Figures 8 and 9, the distribution trends of the resistance values ​​of the serval head are different, so the determination unit 43 determines that the thermal head 14 has been replaced. As a result, the determination unit 43 can automatically determine whether or not the thermal head 14 needs to be replaced by using the distribution trend of the resistance values.

[0057] The above-described embodiment can be modified as needed by partially changing the configuration or functions of each of the above-described devices. Therefore, several modifications of the above-described embodiment will be described below as other embodiments. The following mainly focuses on differences from the above-described embodiment, and detailed descriptions of commonalities with the content already described will be omitted. The modifications described below may be implemented individually or in appropriate combination.

[0058] (Variation 1) In the above-described embodiment, the determination unit 43 determines whether the thermal head needs to be replaced by calculating the difference between the reference resistance value and the measured resistance value. The determination unit 43 also determines whether the thermal head needs to be replaced by comparing the distribution trend of the reference resistance value with the distribution trend of the calculated resistance value. However, the present invention is not limited to this. For example, the determination unit 43 may determine whether the thermal head needs to be replaced by using the least squares error method between the reference resistance value and the measured resistance value.

[0059] (Variation 2) In the above-described embodiment, when the determination unit 43 determines that the thermal head has been replaced, the registration unit 42 registers the resistance value measured by the measurement unit 41 at the time the determination unit 43 made the determination as the reference resistance value, but this is not limited to this. For example, the registration unit 42 registers the resistance value measured by the measurement unit 41 as the reference resistance value each time it is measured. Furthermore, the determination unit 43 may determine whether the thermal head has been replaced based on the trend of change between the reference resistance value registered by the registration unit 42 (the previous measurement result) and the resistance value of each heater measured by the measurement unit 41 (the current measurement result). This can achieve the same effects as the above-described embodiment.

[0060] (Variation 3) For example, the measurement unit 41 stores the measurement results of the resistance values ​​of the heaters measured by the measurement unit 41 as a table in the auxiliary storage device 35. It is also possible to refer to the table for the change trend of the resistance value of each heater, and determine whether the thermal head has been replaced based on the change trend of the resistance value measured by the measurement unit 41. This makes it possible to achieve the same effects as the above-mentioned embodiment.

[0061] In the above embodiment, the control program executed by the printer 1 may be provided by being recorded on a computer-readable recording medium such as a CD-ROM. Also, the control program executed by the printer 1 of the above embodiment may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network, or may be provided via a network such as the Internet.

[0062] Although an embodiment of the present invention has been described above, this embodiment is presented as an example and is not intended to limit the scope of the invention. This embodiment can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. This embodiment and its modifications are included within the scope and spirit of the invention, and are also included in the inventions described in the claims and their equivalents. [Explanation of symbols]

[0063] 1. Printer 2 Upper housing 3 Lower housing 4 One end side 5 Control section 6 Operation buttons 7 Issuance Port 8. Receipts 11 Holding part 12 Guide roller 13 Platen 14 Thermal head 15 cutters 16 Thermal paper 18 Conveyor 31 CPU 32 ROM 33 RAM 34 Interface 35 Auxiliary storage device 41 Measuring part 42 Registration Department 43 Judgment Department 44 Update section 45 Information Department 46 Calculation section [Prior art documents] [Patent documents]

[0064] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-201017

Claims

1. In a printer equipped with a thermal head having a plurality of heaters arranged in a line, a measuring unit that measures the resistance value of each of the heaters; a storage unit that stores operational information indicating an operational state of the thermal head; a determination unit that determines whether the thermal head has been replaced based on a change tendency between a reference resistance value previously measured by the measurement unit and the resistance value of each of the heaters measured by the measurement unit; and an update unit that updates the operational information when the determination unit determines that the thermal head has been replaced; A printer comprising:

2. the measurement unit measures the resistance value when the printer is started up; The printer of claim 1 .

3. a registration unit that registers the reference resistance value in a nonvolatile storage medium; 3. The printer according to claim 1, wherein the registration unit registers the resistance value measured by the measurement unit when the thermal head is replaced as the reference resistance value in the storage medium.

4. a calculation unit that calculates a distribution tendency of the resistance values ​​of the heaters based on the resistance values ​​measured by the measurement unit, the determination unit determines whether the thermal head has been replaced based on the distribution tendency of the reference resistance value calculated by the calculation unit and the distribution tendency of the resistance value measured by the measurement unit. The printer according to any one of claims 1 to 3.

5. a notification unit that notifies the user that the thermal head has been replaced when the determination unit determines that the thermal head has been replaced; The printer according to any one of claims 1 to 4.

6. A computer for a printer equipped with a thermal head having a plurality of heaters arranged in a line, a measuring step of measuring a resistance value of each of the heaters; a storage step of storing operational information indicating an operational state of the thermal head; a determination step of determining whether the thermal head has been replaced based on a change tendency between a reference resistance value previously measured in the measurement step and the resistance value of each of the heaters measured in the measurement step; an updating step of updating the operational information when it is determined in the determining step that the thermal head has been replaced; A program that executes the following.

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