Powered Device

Abstract

To provide a power reception device which can receive adequate power according to an operation state of the power reception device.SOLUTION: A flash memory stores a connection time counter. The connection time counter segments and counts connection time with a power supply device in one time of charging to a battery, as an operation state of a power reception device. The power reception device detects a USB specification operation mode of the power supply device, via a cable, when connected with the power supply device via the cable. The power reception device executes first specific processing, and specifies the connection time of a time section corresponding to a counter with the highest value, as a specific value of the operation state, among counters of each time section in the connection time counter. The power reception device determines a power reception current, based on the USB specification operation mode of the detected power supply device, the specified specific value, and a first power reception determination table stored by a ROM.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a power receiving device. [Background technology]

[0002] The power supply system of Patent Document 1 is composed of a power supply device and a power receiving device. The power supply device and the power receiving device are compatible with USB-PD (Universal Serial Bus-Power Delivery), and can supply power from the power supply device to the power receiving device depending on the results of communication between the devices. In the power supply system, the received power received by the power receiving device is determined based on the loss in the connection cable, which is the power receiving path. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-148621 Summary of the Invention [Problem to be solved by the invention]

[0004] The operating status of a power receiving device varies depending on the user who operates the power receiving device. For example, a certain user may operate the power receiving device infrequently. In this case, sufficient power is supplied to the power receiving device even if the received power is reduced. However, in the power supply system described above, the received power is not supplied according to the operating status of the power receiving device. Therefore, depending on the operating status of the power receiving device, excessive received power may be supplied to the power receiving device. This may cause problems such as deterioration of the power receiving device or excessive heat generation in the power receiving device.

[0005] An object of the present invention is to provide a power receiving device that can receive appropriate power depending on the operating status of the power receiving device. [Means for solving the problem]

[0006] A power receiving device according to one embodiment of the present invention is a power receiving device that determines and receives power within the range of a power supply capacity that indicates the power that can be supplied by a power supply device, and is characterized in that it comprises: a memory unit that stores a first operating status that is a past operating status of the power receiving device; a detection means that detects the power supply capacity of the power supply device; a situation determination means that determines a specific value related to the first operating status from the memory unit; and a determination means that determines the received power based on the power supply capacity detected by the detection means and the specific value determined by the situation determination means.

[0007] According to this aspect, the power receiving device stores a first operating status, which is a past operating status. The power receiving device determines the received power based on the power supply capability of the power supply device and a specific value related to the first operating status of the power receiving device. This allows the power receiving device to receive appropriate power depending on the operating status.

[0008] The power receiving device of this aspect may include a battery that is charged with the received power received from the power supply device, and the first operating status may be a connection time between the power receiving device and the power supply device during a single charge of the battery. The power receiving device determines the received power based on the connection time between the power supply device and the battery during a single charge of the battery. This allows the power receiving device to charge the battery with appropriate power depending on the past connection time between the power receiving device and the power supply device.

[0009] In the power receiving device of this aspect, the determining means may determine a lower power within the range of the power supply capacity as the received power, the larger the specific value related to the connection time identified by the situation identifying means. If the power receiving device has been connected to the power supply device for a long time, the determining means determines a lower power within the range of the power supply capacity as the received power. If the power receiving device has been connected to the power supply device for a long time in the past, there is a high possibility that the user will stop charging the battery immediately after starting charging and will not operate the power receiving device. Therefore, the power receiving device can sufficiently charge the battery without heating it with a small received power.

[0010] The power receiving device of this aspect may include a time classification means for classifying the connection times stored in the memory unit into time segments divided by the length of the connection times, and a time counting means for counting the number of times the connection times are classified into each of the time segments by the time classification means, and the situation identification means may identify the connection time in the time segment with the largest number of counts by the time counting means as the specific value. In the power receiving device, it is highly likely that the battery will be charged during the connection time in the time segment with the largest number of counts by the time counting means. The power receiving device determines the receiving power based on the connection time in the time segment with the largest number of counts by the time counting means. This allows the power receiving device to charge the battery with appropriate power.

[0011] In the power receiving device of this aspect, the situation determination means may determine the average connection time stored in the storage unit as the specific value. The power receiving device determines the receiving power based on the average past connection time with the power supply device. Since excessive power is prevented from being received by the battery, the power receiving device can charge the battery with appropriate power.

[0012] The power receiving device of this aspect includes a battery that is charged with the received power received from the power supply device, and a printing unit that is driven by the power stored in the battery and prints an image on a medium, and the first operating state may be a first printing volume printed by the printing unit using the power stored in the battery after a single charge. In the power receiving device, after the battery is charged, the printing unit prints on the medium. The power receiving device determines the received power based on the first printing volume from the past. This allows the power receiving device to charge the battery with appropriate power according to the first printing volume.

[0013] In the power receiving device of this aspect, the determining unit may determine a smaller power within the range of the power supply capacity as the received power, the smaller the specific value for the first printing volume identified by the situation identifying unit. When the first printing volume is small, the power receiving device determines a smaller power within the range of the power supply capacity as the received power. If the first printing volume has been small in the past, the user is likely to frequently charge the power receiving device after completing charging of the battery. Therefore, the power receiving device can print using its printing unit even if the battery is only charged a small amount at a time. Therefore, the power receiving device can charge the battery to a level that allows printing using the printing unit without causing heat generation in the battery.

[0014] The power receiving device of this aspect may include a quantity classification means for classifying the first printing amounts stored in the memory unit into quantity categories divided by the size of the first printing amounts, and a quantity counting means for counting the number of times the first printing amounts have been classified into each of the quantity categories by the quantity classification means, and the situation identification means may identify the first printing amount in the quantity category with the largest number of counts by the quantity counting means as the specific value. In the power receiving device, the printing unit is likely to print only the first printing amount in the quantity category with the largest number of counts by the quantity counting means. The power receiving device determines the received power based on the first printing amount in the quantity category with the largest number of counts by the quantity counting means. This allows the power receiving device to charge a battery with appropriate power.

[0015] In the power receiving device of this aspect, the situation determination means may determine the average value of the first printing volume stored in the memory unit as the specific value. The power receiving device determines the receiving power based on the average value of the first printing volume printed by the printing unit during a single charge of the battery in the past. This prevents the battery from receiving excessive power compared to the power consumed by printing, allowing the power receiving device to charge the battery with appropriate power.

[0016] In the power receiving device of this aspect, the situation identification means may identify the maximum value of the first printing amount stored in the memory unit as the specific value. The power receiving device determines the receiving power based on the maximum value of the first printing amount printed by the printing unit in a single charge of the battery in the past. In the power receiving device, it is likely that the printing unit will print an amount smaller than the maximum value of the first printing amount in the past. Since excessive receiving power is prevented from being received by the battery, the power receiving device can charge the battery with appropriate power.

[0017] The power receiving device of this aspect may include an acquisition means for acquiring a second operating status, which is a current operating status of the power receiving device, and the status identification means may identify the specific value based on the second operating status acquired by the acquisition means. The power receiving device acquires the second operating status, which is the current operating status. The power receiving device identifies the specific value related to the first operating status based on the second operating status. This allows the power receiving device to receive appropriate power according to the first operating status and the second operating status.

[0018] The power receiving device of this aspect includes a battery that is charged with the received power received from the power supply device, and a printing unit that is driven by the power stored in the battery and prints an image on a medium. The first operating status is a second print volume that the printing unit prints in each time period of a day using the power of the charged battery, and the second operating status is a connection start time when the power receiving device is currently connected to the power supply device for charging the battery. The power receiving device may include a time period identification means that identifies which time period the connection start time acquired by the acquisition means corresponds to, and the status identification means may identify the second print volume for the time period identified by the time period identification means as the specific value. In the power receiving device, after the battery is charged, the printing unit prints on a medium. The power receiving device identifies which time period the connection start time when the power supply device is connected corresponds to. The power receiving device determines the received power based on the second print volume that the printing unit printed in the time period corresponding to the connection start time. This allows the power receiving device to charge the battery with an appropriate amount of power depending on the frequency of printing during the time period when the power supply device is connected.

[0019] In the power receiving device of this aspect, the determination unit may determine a smaller power within the range of the power supply capacity as the received power, the smaller the second printing volume identified by the situation identification unit. If the second printing volume is small during a time period when the power supply device is connected, the power receiving device determines a smaller power within the range of the power supply capacity as the received power. If the power supply device is connected during a time period when the second printing volume is small, the user is unlikely to print using the printing unit during that time period. Therefore, the power receiving device can sufficiently charge the battery without heating it with the small received power.

[0020] In the power receiving device of this aspect, the determining means may determine the received power by calculating the power supply capacity detected by the detecting means and the specific value identified by the status identifying means. The power receiving device determines the received power by calculating the power supply capacity of the power supply device and the specific value related to the operating status of the power receiving device. This allows the power receiving device to receive more appropriate power depending on the operating status.

[0021] The power receiving device of this aspect may include a second storage unit that stores a database indicating the relationship between the power supply capacity, the specific value, and the received power, and the determination unit may determine the received power by referring to the database stored in the second storage unit based on the power supply capacity detected by the detection unit and the specific value identified by the situation identification unit. The power receiving device determines the received power by referring to the database stored in the second storage unit based on the power supply capacity of the power supply device and the specific value related to the operating situation of the power receiving device. This allows the power receiving device to receive appropriate power according to the operating situation in a simple manner.

[0022] In the power receiving device of this aspect, the determination means may include a provisional determination means for determining a provisional received power, which is the provisional received power, based on the power supply capacity detected by the detection means and the specific value determined by the situation determination means, a loss determination means for determining a loss that would occur if the provisional received power determined by the provisional determination means were received from the power supply device, a determination means for determining whether the loss determined by the loss determination means is equal to or greater than a predetermined threshold, and a final determination means for determining, if the determination means determines that the loss exceeds the predetermined threshold, a power smaller than the provisional received power determined by the provisional determination means as the received power. Depending on the connection state with the power supply device, the power receiving device may receive power greater than the received power. The power receiving device determines the provisional received power based on the power supply capacity of the power supply device and the operating status of the power receiving device, and determines the loss that would occur if the provisional received power were received. When the identified loss is equal to or greater than a predetermined threshold, the power receiving device determines, as the received power, a power that is smaller than the tentative received power determined by the tentative determination means, thereby preventing the power receiving device from receiving excessive power. [Brief explanation of the drawings]

[0023] [Figure 1] 2 is a diagram showing an electrical system of the power receiving device 1. FIG. [Figure 2] 1 is a diagram illustrating USB standard operating modes. [Figure 3] 2 is a block diagram showing the electrical configuration of the power receiving device 1. FIG. [Figure 4] 10 is a diagram illustrating a flow from when a power receiving device determines the amount of power to be received depending on the operating status to when the power receiving device starts receiving power from a power feeding device. FIG. [Figure 5] FIG. 2 is a conceptual diagram of a connection time counter 71. [Figure 6] 10 is a conceptual diagram of a first power reception determination table 81. FIG. [Figure 7] 10 is a flowchart of a first power receiving process. [Figure 8] FIG. 10 is a conceptual diagram of a sheet number counter 72. [Figure 9] 10 is a conceptual diagram of a second power reception determination table 82. FIG. [Figure 10] 10 is a flowchart of a second power receiving process. [Figure 11] 10 is a flowchart of a first printing process. [Figure 12] FIG. 10 is a conceptual diagram of a time zone counter 73. [Figure 13] 10 is a conceptual diagram of a third power reception determination table 83. FIG. [Figure 14] 10 is a flowchart of a third power receiving process. [Figure 15] 10 is a flowchart of a second printing process. DETAILED DESCRIPTION OF THE INVENTION

[0024] A first embodiment of the present invention will be described below with reference to the drawings. The drawings are used to explain technical features that can be adopted by the present invention. The configurations of the devices shown in the drawings are merely illustrative examples and are not intended to be limiting.

[0025] <Power receiving device 1> The power receiving device 1 is a thermal transfer printer that is driven by power stored in a battery 63. The power receiving device 1 can print characters (objects such as letters, symbols, numbers, and figures) on a print medium (for example, a thermal label). The power receiving device 1 charges the battery 63 with the power received from the power supply device 99.

[0026] The configuration of the power receiving device 1 will be described with reference to FIG. 1. The power receiving device 1 includes a housing 2. An input unit 5, a display unit 6, and a USB connector 91 are provided on the surface of the housing 2. The input unit 5 can accept user operations. The display unit 6 is a liquid crystal display that displays various information. The USB connector 91 is a connection port for connecting to a USB device such as a power supply device 99 via a cable 98 that conforms to the USB standard. The USB connector 91 relays the received power received from the power supply device 99 to the inside of the power receiving device 1.

[0027] Inside the housing 2 are a mounting unit 3, a print head 21, a CPU 51, a USB PD controller 60, a first line 33, and a second line 34. A battery 63 can be detachably attached to the mounting unit 3. The battery 63 is, for example, a lithium-ion battery or an electric double-layer capacitor. The print head 21 generates heat using power supplied from the battery 63, enabling it to print on the print medium.

[0028] The CPU 51 performs overall control of the power receiving device 1. When power supply conforming to the USB PD standard is possible from the power supply device 99 via the cable 98, the USB PD controller 60 negotiates with the power supply device 99 regarding the received power to be received from the power supply device 99 under the control of the CPU 51.

[0029] The first line 33 connects the battery 63 attached to the attachment unit 3 to the USB connector 91. The first line 33 transmits the received power relayed by the USB connector 91 to the battery 63 attached to the attachment unit 3. A switch 35 and a charging circuit 61 are provided on the first line 33. The switch 35 is provided upstream of the charging circuit 61 in the power transmission from the USB connector 91 to the battery 63 on the first line 33.

[0030] The switch 35 switches between an ON state and an OFF state in response to an instruction output from the CPU 51. When the switch 35 is in the ON state, the first line 33 transmits the received power relayed by the USB connector 91 to the charging circuit 61. When the switch 35 is in the OFF state, the first line 33 stops transmitting the received power relayed by the USB connector 91 to the charging circuit 61.

[0031] The charging circuit 61 is an electronic circuit for controlling charging of the battery 63. The charging circuit 61 includes an FET 62, which is a switching element. The FET 62 is, for example, a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor). The FET 62 switches between an ON state and an OFF state in response to an instruction output from the CPU 51. When the FET 62 is in the ON state, the first line 33 transmits the received power transmitted to the charging circuit 61 to the battery 63. When the FET 62 is in the OFF state, the first line 33 stops transmitting the received power transmitted to the charging circuit 61 to the battery 63.

[0032] The second line 34 connects the battery 63 attached to the attachment portion 3 to the print head 21. The second line 34 transmits power discharged from the battery 63 to the print head 21. The second line 34 is provided with a drive circuit 31. The drive circuit 31 is an electronic circuit for controlling the drive of the print head 21. The drive circuit 31 includes an FET 32, which is a switching element. The FET 32 is, for example, a MOSFET. The FET 32 switches between an ON state and an OFF state in response to an instruction output from the CPU 51. When the FET 32 is in the ON state, the second line 34 transmits power discharged from the battery 63 to the print head 21. When the FET 32 is in the OFF state, the second line 34 stops transmitting power from the battery 63 to the print head 21.

[0033] <Power Supply Device 99> The power supply device 99 is, for example, a general-purpose personal computer, a mobile terminal, a tablet terminal, etc. The power supply device 99 supplies power to the power receiving device 1 connected via a cable 98. The power supply device 99 supplies power corresponding to one of the USB standard operation modes shown in FIG. 2 to the power receiving device 1.

[0034] <Electrical configuration of power receiving device 1> 3, the electrical configuration of the power receiving device 1 will be described. The power receiving device 1 includes a CPU 51, a ROM 52, a RAM 53, a flash memory 54, a USB PD controller 60, and an input / output interface (hereinafter referred to as an input / output I / F) 59. The ROM 52, the RAM 53, the flash memory 54, the USB PD controller 60, and the input / output I / F 59 are each electrically connected to the CPU 51.

[0035] The CPU 51 executes various programs for controlling the power receiving device 1. The ROM 52 stores various programs, dot patterns of characters to be printed, a first power receiving determination table 81 (see FIG. 6), a second power receiving determination table 82 (see FIG. 9), and a third power receiving determination table 83 (see FIG. 13), which will be described later, and the like. The RAM 53 temporarily stores flags such as a charging flag, which will be described later, the number of sheets printed by the print head 21 on the print medium, various calculation results, and the like. The flash memory 54 stores various settings of the power receiving device 1, a connection time counter 71 (see FIG. 5), a sheet number counter 72 (see FIG. 8), and a time period counter 73 (see FIG. 12), which will be described later, and the like. The USB PD controller 60 communicates with the power supply device 99 in response to instructions output by the CPU 51.

[0036] The CPU 51 is electrically connected to the input unit 5, display unit 6, clock 41, switch 35, drive circuits 12, 31, charging circuit 61, and USB connector 91 via the input / output I / F 59. The input unit 5 inputs the results of accepting user operations to the CPU 51. The display unit 6 displays various information in accordance with instructions output by the CPU 51. The clock 41 inputs a clock signal for measuring time to the CPU 51. The switch 35 switches between an ON state and an OFF state in accordance with instructions output by the CPU 51. The voltage detection unit 64 detects the magnitude of the voltage supplied from the charging circuit 61 to the battery 63 and inputs the detected voltage to the CPU 51.

[0037] The drive circuit 12 is electrically connected to the carry motor 11. The CPU 51 controls the drive circuit 12 to control the transport of the print medium by the carry motor 11. The drive circuit 31 is electrically connected to the print head 21. The drive circuit 31 includes an FET 32. The CPU 51 controls the drive circuit 31 to switch the FET 32 between an ON state and an OFF state. The charging circuit 61 is electrically connected to a battery 63. The charging circuit 61 includes an FET 62 and a voltage detection unit 64. The CPU 51 controls the charging circuit 61 to switch the FET 62 between an ON state and an OFF state. The voltage detection unit 64 detects the voltage supplied to the battery 63 and inputs it to the CPU 51.

[0038] The power receiving device 1 does not charge the battery 63 and print with the print head 21 simultaneously. When charging the battery 63, the CPU 51 turns the switch 35 and FET 62 to the ON state and turns the FET 32 to the OFF state (see FIG. 1). Power is supplied from the power supply device 99 via the first line 33, and the battery 63 charges. When printing on the print medium, the CPU 51 turns the switch 35 and FET 62 to the OFF state and turns the FET 32 to the ON state (see FIG. 1). The power receiving device 1 prints on the print medium with the print head 21 while driving the transport motor 11 to transport the print medium.

[0039] The power supply device 99 is electrically connected to the CPU 51 and the USB PD controller 60 via the USB connector 91 and the input / output I / F 59. When the power supply device 99 supports the USB PD standard in the USB standard operation mode shown in FIG. 2 , the CPU 51 communicates with the power supply device 99 via the USB PD controller 60. In this case, the CPU 51 receives power rules related to the power that the power supply device 99 can supply. Under the control of the CPU 51, the USB PD controller 60 requests the power supply device 99 to select the desired receiving power from the power supply device 99 based on the power rules, and receives the power. When the power supply device 99 supports a USB standard operation mode other than the USB PD standard shown in FIG. 2 , the CPU 51 receives the desired receiving power from the power supply device 99 within the power range compatible with the USB standard operation mode.

[0040] <Flow until power receiving device 1 receives power> 4 to 6, a flow until the power receiving device 1 starts receiving power from the power supply device 99 will be described. Before the power receiving device 1 starts receiving power, the FETs 32 and 62 and the switch 35 are all in the OFF state. The power receiving device 1 receives appropriate power from the power supply device 99 according to the operating status of the power receiving device 1, which differs for each user. The operating status may be, for example, the connection time with the power supply device 99 during one charge of the battery 63, the number of pages printed by the print head 21 during one charge of the battery 63, and the frequency of printing by the print head 21 during the time period when charging of the battery 63 begins. The power receiving device 1 of the first embodiment receives appropriate power from the power supply device 99 according to the connection time with the power supply device 99 during one charge of the battery 63.

[0041] When the power receiving device 1 is connected to the power supply device 99 via the cable 98, it detects the USB standard operation mode of the power supply device 99 (P1). The power receiving device 1 determines the receiving voltage based on the USB standard operation mode of the power supply device 99 and the amount of power that the cable 98 can transmit (P2). If the power supply device 99 supports the USB PD standard of the USB standard operation mode shown in FIG. 2, the power receiving device 1 determines the receiving voltage to be 15 V. If the power supply device 99 supports a USB standard operation mode other than the USB PD standard shown in FIG. 2, the power receiving device 1 determines the receiving voltage to be 5 V.

[0042] The power receiving device 1 identifies a specific value (P3). The specific value is a specific numerical value related to the operating status of the power receiving device 1. The power receiving device 1 identifies the specific value based on the operating status. The power receiving device 1 of the first embodiment identifies the specific value related to the connection time based on the connection time with the power supply device 99 during one charge of the battery 63.

[0043] The power receiving device 1 of the first embodiment refers to a connection time counter 71 (see FIG. 5) when identifying a specific value. The connection time counter 71 is stored in the flash memory 54. The connection time counter 71 counts the connection time with the power supply device 99 by dividing it into segments. The connection time with the power supply device 99 is measured each time the battery 63 is charged. Hereinafter, the divided connection time is referred to as a time segment. In the connection time counter 71, the time segments are equal to or greater than 0 hours but less than 2 hours, equal to or greater than 2 hours but less than 3 hours, equal to or greater than 3 hours but less than 4 hours, and equal to or greater than 4 hours.

[0044] When receiving power from the power supply device 99 this time, the power receiving device 1 specifies, as the specific value, the time segment corresponding to the highest counter value in the connection time counter 71. In the case of the connection time counter 71 shown in FIG. 5, the power receiving device 1 specifies, as the specific value, a time segment that is equal to or greater than 3 hours and less than 4 hours.

[0045] The power receiving device 1 provisionally determines the receiving current based on the USB standard operation mode of the power supply device 99 detected in P1 and the specific value of the operating condition identified in P3 (P4). When provisionally determining the receiving current, the power receiving device 1 refers to a first power receiving determination table 81 (see FIG. 6) stored in the ROM 52. For example, if the USB standard operation mode of the power supply device 99 is the USB Type-C (3 A) standard and the specific value of the operating condition identified is 3 hours or more but less than 4 hours, the power receiving device 1 provisionally determines the receiving current to be 1.0 A. In the first power receiving determination table 81, the longer the connection time with the power supply device 99, which is the specific value of the operating condition, the smaller the current provisionally determined to be within the range of current that can be output in the USB standard operation mode.

[0046] The power receiving device 1 determines whether the provisionally determined receiving current is 0.5 A (P5). 0.5 A is the minimum current that can be transmitted via the cable 98, which is a USB cable.

[0047] If the provisionally determined receiving current exceeds 0.5 A, the power receiving device 1 executes a load test (P6). In the load test, the power receiving device 1 notifies the power supply device 99 of the receiving voltage determined in P2 and the receiving current provisionally determined in P4. The power supply device 99 outputs the power notified from the power receiving device 1 to the power receiving device 1. The power receiving device 1 turns the switch 35 and the FET 62 on for one second, and then turns the switch 35 and the FET 62 off. For one second while the switch 35 and the FET 62 are on, power is supplied from the power supply device 99 to the battery 63. The power receiving device 1 detects the voltage supplied to the battery 63 using the voltage detection unit 64. The power receiving device 1 calculates a voltage drop by subtracting the voltage detected by the voltage detection unit 64 from the receiving voltage notified to the power supply device 99.

[0048] The power receiving device 1 determines whether the load test is successful based on the magnitude relationship between the voltage drop and a threshold (P7). The threshold is a predetermined value based on the USB standard operation mode of the power supply device 99 detected in P1. If the voltage drop is equal to or less than the threshold, the power receiving device 1 determines that the load test is successful. If the voltage drop exceeds the threshold, the power receiving device 1 determines that the load test is unsuccessful.

[0049] If the load test is determined to be unsuccessful, the power receiving device 1 subtracts 0.5 A from the provisionally determined receiving current and determines the resulting current as the receiving current (P8). The power receiving device 1 then determines again whether the receiving current after subtracting 0.5 A is 0.5 A.

[0050] If the receiving current is 0.5 A, or if a receiving current exceeding 0.5 A is determined to pass the load test, the power receiving device 1 officially determines the provisionally determined receiving current as the receiving current for charging the battery 63 (P9).

[0051] The power receiving device 1 notifies the power supply device 99 of the received power that is a combination of the received voltage determined in P2 and the received current determined in P9 (P10). The power supply device 99 outputs the received power notified by the power receiving device 1 to the power receiving device 1. The power receiving device 1 turns on the switch 35 and the FET 62. The received power is supplied from the power supply device 99 to the battery 63 (P11).

[0052] <First incoming call processing> 7, the first power receiving process executed by the CPU 51 will be described. The first power receiving process is a process in which the power receiving device 1 receives power from the power supply device 99 based on the connection time with the power supply device 99 during one charge of the battery 63. At the start of the first power receiving process, the FETs 32 and 62 and the switch 35 are all in the OFF state. When the power supply device 99 is connected to the USB connector 91 via the cable 98, the CPU 51 reads out a program stored in the ROM 52 and executes the first power receiving process.

[0053] When the first power receiving process is started, the CPU 51 starts measuring the connection time with the power supply device 99 (S1). The CPU 51 detects the USB standard operation mode of the power supply device 99 via the cable 98 (S2). The CPU 51 determines the receiving voltage based on the detected USB standard operation mode of the power supply device 99 and the amount of power that the cable 98 can transmit (S3).

[0054] The CPU 51 executes a first identification process (S4). In the first identification process, the CPU 51 identifies, as a specific value, the time segment corresponding to the highest counter value in the connection time counter 71 (see FIG. 5). The CPU 51 provisionally determines the receiving current based on the USB standard operation mode of the power supply device 99 detected in S2, the specific value identified in S4, and a first power receiving determination table 81 (see FIG. 6) stored in the ROM 52 (S5).

[0055] The CPU 51 determines whether the receiving current provisionally determined in S5 is 0.5 A (S6). If the receiving current provisionally determined is 0.5 A (S6: YES), the CPU 51 shifts the process to S10.

[0056] If the provisionally determined receiving current exceeds 0.5 A (S6: NO), the CPU 51 executes a load test (S7). The CPU 51 determines whether the load test is passed (S8). If the voltage drop in the load test is equal to or less than the threshold, the CPU 51 determines that the load test is passed (S8: YES). The CPU 51 proceeds to S10.

[0057] If the voltage drop in the load test exceeds the threshold, the CPU 51 determines that the load test has failed (S8: NO). The CPU 51 determines the receiving current to be the current obtained by subtracting 0.5 A from the provisionally determined receiving current (S9). The CPU 51 returns the process to the determination in S6. If the receiving current after subtracting 0.5 A is 0.5 A (S6: YES), the CPU 51 proceeds to S10. If the receiving current after subtracting 0.5 A exceeds 0.5 A (S6: NO), the CPU 51 executes the load test process again (S7).

[0058] The CPU 51 determines the receiving current (S10). The CPU 51 notifies the power supply device 99 of the received power based on the determined combination of the receiving voltage and receiving current (S11). The power supply device 99 outputs the power notified from the power receiving device 1 to the power receiving device 1. The CPU 51 turns on the switch 35 and the FET 62. The power supply device 99 starts supplying the received power notified in S11 to the battery 63 (S12).

[0059] The CPU 51 determines whether the cable 98 has been unplugged and the connection with the power supply device 99 has been released (S13). The CPU 51 repeats the determination in S13 until it determines that the connection with the power supply device 99 has been released (S13: NO). If it determines that the connection with the power supply device 99 has been released (S13: YES), the CPU 51 ends the counting of the connection time with the power supply device 99, which began in S1 (S14).

[0060] The CPU 51 executes a connection time classification process (S15). In the connection time classification process, the CPU 51 classifies the measured connection time with the power supply device 99 into a corresponding time segment from among the multiple time segments in the connection time counter 71. The CPU 51 adds 1 to the counter value corresponding to the time segment into which the connection time was classified in S15, and stores the counter value in the flash memory 54, thereby updating the connection time counter 71 (S16). The CPU 51 ends the first power receiving process.

[0061] <Actions and Effects of First Embodiment> In the power receiving device 1 of the first embodiment, the flash memory 54 stores, as an operating status of the power receiving device 1, a connection time counter 71 that counts a connection time with the power supply device 99 in a single charging of the battery 63 by dividing the connection time into segments. When the power receiving device 1 is connected to the power supply device 99 via the cable 98, the CPU 51 of the power receiving device 1 detects the USB standard operation mode of the power supply device 99 via the cable 98 (S2). The CPU 51 executes a first determination process to determine, as a specific value, the connection time of the time segment corresponding to the counter with the highest value among the counters for each time segment in the connection time counter 71 (S4). The CPU 51 determines the power receiving current based on the detected USB standard operation mode of the power supply device 99, the determined specific value, and a first power receiving determination table 81 stored in the ROM 52 (S5 to S10). According to this embodiment, the power receiving device 1 stores, as a past operating status, a connection time counter 71 relating to the connection time with the power supply device 99 in a single charging of the battery 63. The power receiving device 1 detects the USB standard operation mode, which is the power supply capability of the power supply device 99. The power receiving device 1 determines the received power based on a specific value related to the connection time with the power supply device 99, within the range of power that the power supply device 99 can supply. This allows the power receiving device 1 to receive appropriate power depending on the operating status.

[0062] The power receiving device 1 regards the connection time with the power supply device 99 during one charging of the battery 63 as the operating status of the power receiving device 1. The power receiving device 1 determines the received power based on the connection time with the power supply device 99 during one charging of the battery 63. This allows the power receiving device 1 to charge the battery 63 with appropriate power depending on the past connection time with the power supply device 99.

[0063] In the first power receiving determination table 81, the longer the connection time with the power supply device 99, which is a specific value of the operating status, the smaller the current determined as the received current within the range of current that can be output in the USB standard operating mode. If the connection time with the power supply device 99 has been long, there is a high possibility that the user will stop charging the battery 63 immediately after starting charging the battery 63 and will not operate the power receiving device 1. Therefore, the power receiving device 1 can sufficiently charge the battery 63 without heating it with a small received power.

[0064] When charging the battery 63, the CPU 51 executes a connection time classification process to classify the measured connection time with the power supply device 99 into a corresponding time segment among the multiple time segments in the connection time counter 71 (S15). The CPU 51 updates the connection time counter 71 by adding 1 to the counter value corresponding to the time segment into which the connection time has been classified and storing the result in the flash memory 54 (S16). In a first identification process, the CPU 51 identifies the connection time of the time segment corresponding to the counter with the highest value among the counters for each time segment in the connection time counter 71 as a specific value (S4). When charging the battery 63, it is highly likely that charging will be performed during the connection time of the time segment corresponding to the counter with the highest value in the connection time counter 71. The power receiving device 1 determines the received power based on the connection time of the time segment corresponding to the counter with the highest value in the connection time counter 71. This enables the power receiving device 1 to charge the battery 63 with appropriate power.

[0065] The CPU 51 determines the receiving current based on the USB standard operation mode of the power supply device 99 detected via the cable 98, a specific value determined from the operating status, and the first power receiving determination table 81 stored in the ROM 52. This allows the power receiving device 1 to receive appropriate power according to the operating status in a simple manner.

[0066] The CPU 51 provisionally determines the receiving current based on the USB standard operation mode of the power supply device 99 detected via the cable 98, a specific value determined from the operating status, and the first power receiving determination table 81 stored in the ROM 52 (S5). The CPU 51 executes a load test and calculates a voltage drop (S7). The CPU 51 determines whether the load test passes or fails by determining whether the voltage drop exceeds a threshold (S8). If the CPU 51 determines that the load test executed with the provisionally determined receiving current fails because the voltage drop exceeds the threshold, it subtracts 0.5 A from the provisionally determined receiving current to set the receiving current as the current (S9). If the CPU 51 determines that the load test executed with the provisionally determined receiving current passes because the voltage drop is equal to or less than the threshold, it finally determines the provisionally determined receiving current as the current (S10). This prevents the power receiving device 1 from receiving excessive power from the power supply device 99.

[0067] <Modification of the first embodiment> The first embodiment is not limited to the above and various modifications are possible. The power receiving device 1 may appropriately change the method for specifying the specific value in the first specification process. For example, the power receiving device 1 may calculate an average value of past connection times with the power supply device 99 and specify the average value as the specific value in the first specification process. In this case, the flash memory 54 stores the timed connection time with the power supply device 99 when charging the battery 63. The power receiving device 1 determines the received power based on the average value of past connection times with the power supply device 99. This prevents the battery 63 from receiving excessive power. Therefore, the power receiving device 1 can charge the battery 63 with appropriate power.

[0068] In the first embodiment, the CPU 51 determines that the load test has failed when the voltage drop has exceeded the threshold value, but it may also determine that the load test has failed when the voltage drop is equal to or greater than the threshold value.

[0069] Second Embodiment A second embodiment of the present invention will now be described. The power receiving device 1 of the second embodiment differs from the power receiving device 1 of the first embodiment in that the operating status is the number of pages printed by the print head 21 per charge of the battery 63 (number of printed pages), that a second power receiving process is executed when receiving power from the power supply device 99, and that a first printing process is executed. Below, configurations having the same functions as the power receiving device 1 of the first embodiment and processes similar to the first power receiving process are assigned the same reference numerals as the power receiving device 1 of the first embodiment, and descriptions thereof will be omitted or simplified.

[0070] The identification of the operating status and the provisional determination of the provisional current in the second embodiment will be described with reference to Figures 4, 8, and 9. The power receiving device 1 in the second embodiment identifies a specific value relating to the number of sheets printed per charge of the battery 63 based on the sheet count counter 72 (see Figure 8) (P3, see Figure 4).

[0071] The sheet number counter 72 is stored in the flash memory 54. The sheet number counter 72 counts the number of printed sheets per charge of the battery 63 in categories. Hereinafter, the categoryed number of printed sheets will be referred to as the sheet number category. The sheet number counter 72 has the following number categories: 0 to 5 sheets, 6 to 10 sheets, 11 to 15 sheets, and 16 or more sheets.

[0072] As a specific value of the operating status, the power receiving device 1 sets the specific value to the number category corresponding to the counter with the highest value among the counters for each number category in the number counter 72. In the case of the number counter 72, the power receiving device 1 sets 11 to 15 as the specific value.

[0073] The power receiving device 1 provisionally determines the power receiving current based on the detected USB standard operation mode of the power supply device 99, the specific value determined from the operating status, and the second power receiving determination table 82 (see FIG. 9) (P4, see FIG. 4). The second power receiving determination table 82 is stored in the ROM 52. For example, if the USB standard operation mode of the power supply device 99 is the USB Type-C (3 A) standard and the specific value of the determined operating status is 11 to 15 sheets, the power receiving device 1 provisionally determines the power receiving current to be 1.5 A. In the second power receiving determination table 82, the smaller the number of printed sheets, which is the specific value of the operating status, the smaller the provisionally determined power receiving current is within the range of current that can be output in the USB standard operation mode.

[0074] <Second power receiving process> The second power receiving process executed by the CPU 51 will be described with reference to Figure 10. The second power receiving process is a process in which the power receiving device 1 receives power from the power supply device 99 based on the number of pages printed by the print head 21 per charge of the battery 63. At the start of the second power receiving process, the FETs 32 and 62 and the switch 35 are all in the OFF state. When the power supply device 99 is connected to the USB connector 91 via the cable 98, the CPU 51 reads out a program stored in the ROM 52 and executes the second power receiving process.

[0075] When the second power receiving process is started, the CPU 51 detects the USB standard operation mode of the power supply device 99 (S2). The CPU 51 determines the power receiving voltage (S3).

[0076] The CPU 51 executes a second determination process (S24). In the second determination process, the CPU 51 determines the number of printed sheets for the sheet count category corresponding to the counter with the highest value among the counters for each sheet count category in the sheet count counter 72 (see FIG. 8) as a specific value. The CPU 51 provisionally determines the receiving current based on the detected USB-standard operating mode of the power supply device 99, the specific value determined in S24, and the second power receiving determination table 82 (see FIG. 9) stored in the ROM 52 (S5).

[0077] The CPU 51 determines whether the receiving current provisionally determined in S5 is 0.5 A (S6). If the provisionally determined receiving current is 0.5 A (S6: YES), the CPU 51 shifts the process to S10. If the provisionally determined receiving current exceeds 0.5 A (S6: NO), the CPU 51 executes a load test (S7). The CPU 51 determines whether the load test executed in S7 is passed (S8). If the load test is judged to be passed (S8: YES), the CPU 51 shifts the process to S10. If the load test is judged to be failed (S8: NO), the CPU 51 subtracts 0.5 A from the provisionally determined receiving current and sets the result as the receiving current (S9). The CPU 51 returns the process to the judgment of S6.

[0078] The CPU 51 determines the receiving current (S10). The CPU 51 notifies the power supply device 99 of the receiving power corresponding to the determined combination of the receiving voltage and receiving current (S11). The power supply device 99 outputs the power notified by the power receiving device 1 to the power receiving device 1. The CPU 51 turns on the switch 35 and the FET 62 to start supplying the receiving power to the battery 63 (S12).

[0079] The CPU 51 turns ON the charging flag stored in the RAM 53 (S25). The charging flag is set to 1 and turned ON when the battery 63 is charged, and is set to 0 and turned OFF when printing is performed by the print head 21 after the battery 63 is charged. The CPU 51 then ends the second power receiving process.

[0080] <First printing process> The first printing process executed by the CPU 51 will be described with reference to Figure 11. The first printing process is a process in which the power receiving device 1 of the second embodiment prints on a print medium using the print head 21. When the first printing process starts, the power receiving device 1 and the power supply device 99 are not connected via the cable 98, and the FETs 32 and 62 and the switch 35 are all in the OFF state. When the user operates the input unit 5 and issues a command to execute the first printing process, the CPU 51 reads out a program stored in the ROM 52 and executes the first printing process.

[0081] When the first print process is started, the CPU 51 determines whether the current printing will be performed immediately after charging the battery 63 (S31). The CPU 51 makes the determination in S31 based on the charge flag stored in the RAM 53. If the charge flag is ON and the current printing will be performed immediately after charging the battery 63 (S31: YES), the CPU 51 initializes the counter value of the sheet number counter 72 (see FIG. 8) stored in the flash memory 54 to 0 (S32). The CPU 51 turns OFF the charge flag stored in the RAM 53 (S33) and proceeds to S34. If the charge flag is OFF and the current printing will not be performed immediately after charging the battery 63 (S31: NO), the CPU 51 proceeds to S34.

[0082] The CPU 51 acquires the number of sheets printed by the print head 21 stored in RAM 53 (S34). The CPU 51 executes a sheet count classification process (S35). In the sheet count classification process, the CPU 51 classifies the number of sheets printed acquired in S34 into the corresponding sheet count category among the multiple sheet count categories in the sheet count counter 72. The CPU 51 adds 1 to the counter value corresponding to the sheet count category into which the number of sheets printed in S35 was classified, and stores the counter value in flash memory 54, thereby updating the sheet count counter 72 (S36). The CPU 51 executes a printing process (S37). In the printing process, the CPU 51 drives the transport motor 11 and the print head 21 to print on the number of sheets of printing media acquired in S34 while transporting the printing medium.

[0083] <Actions and Effects of Second Embodiment> In the power receiving device 1 of the second embodiment, the number of pages printed by the print head 21 per charge of the battery 63 is used as the operating status of the power receiving device 1. In the power receiving device 1, after the battery 63 is charged, the print head 21 prints on the print medium. The power receiving device 1 determines the receiving power based on the number of pages printed per charge of the battery 63. This allows the power receiving device 1 to charge the battery 63 with appropriate power according to the number of pages printed per charge of the battery 63 up to now.

[0084] In the second power receiving determination table 82, the smaller the number of printed pages, which is a specific value of the operating status, the smaller the current determined as the receiving current within the range of current that can be output in the USB standard operating mode. If the number of printed pages per charge of the battery 63 has been small up to now, the user is likely to charge the battery 63 frequently. Therefore, the power receiving device 1 can print using the print head 21 even if the amount of power charged to the battery 63 per charge is small. Therefore, the power receiving device 1 can charge the battery 63 to an extent that does not cause the battery 63 to heat up and that allows the print head 21 to print.

[0085] When executing the first printing process, the CPU 51 executes a sheet count classification process to classify the current number of printed sheets into a corresponding sheet count category among the multiple sheet count categories in the sheet count counter 72 (S35). The CPU 51 updates the sheet count counter 72 by adding 1 to the counter value corresponding to the sheet count category into which the number of printed sheets has been classified and storing the result in the flash memory 54 (S36). In a second identification process, the CPU 51 identifies the number of printed sheets in the sheet count category corresponding to the counter with the highest value among the counters for each time category in the sheet count counter 72 as a specific value (S24). In the first printing process, the power receiving device 1 is likely to perform printing with the number of printed sheets in the sheet count category corresponding to the counter with the highest value in the sheet count counter 72. The power receiving device 1 determines the received power based on the number of printed sheets in the sheet count category corresponding to the counter with the highest value in the sheet counter 72. This allows the power receiving device 1 to charge the battery 63 with appropriate power.

[0086] <Modification of the second embodiment> The second embodiment is not limited to the above and various modifications are possible. The power receiving device 1 may appropriately change the method for specifying the specific value in the second specification process. For example, in the second specification process, the power receiving device 1 may calculate the average number of pages printed per charge of the battery 63 and specify this average value as the specific value. In this case, the flash memory 54 stores the number of pages printed on the print medium by the print head 21 each time the first printing process is executed. The power receiving device 1 determines the receiving power based on the average number of pages printed per first printing process. This prevents the battery 63 from receiving excessive power compared to the power consumed from the battery 63 during printing. Therefore, the power receiving device 1 can charge the battery with appropriate power.

[0087] As another example of specifying the specific value, the power receiving device 1 may obtain the maximum number of pages printed so far per charge of the battery 63 in the second specifying process and specify this maximum value as the specific value. In this case, the flash memory 54 stores the number of pages printed on the print medium by the print head 21 each time the first printing process is executed. The power receiving device 1 determines the receiving power based on the maximum number of pages printed so far in the first printing process. In the first printing process, the power receiving device 1 is likely to print fewer pages than this maximum number. This prevents the battery 63 from receiving excessive receiving power. Therefore, the power receiving device 1 can charge the battery 63 with appropriate power.

[0088] The operating status in the second embodiment may be related to the amount of printing that the print head 21 does on the print medium. For example, the operating status in the second embodiment may be the number of dots of an image that is printed on the print medium per one charge of the battery 63. The operating status in the second embodiment may also be the number of times the first printing process is performed per one charge of the battery 63.

[0089] Third Embodiment A third embodiment of the present invention will now be described. The power receiving device 1 of the third embodiment differs from the power receiving devices 1 of the first and second embodiments in that the third embodiment executes a third power receiving processing point when receiving power from the power supply device 99, using the frequency of printing performed by the print head 21 during the time period when charging of the battery 63 begins (printing frequency) as the operating status. Below, configurations having similar functions to the power receiving devices 1 of the first and second embodiments, and processes similar to the first power receiving process, second power receiving process, and first printing process, are assigned the same reference numerals as the power receiving devices 1 of the first and second embodiments, and descriptions thereof will be omitted or simplified.

[0090] 4, 12, and 13, the identification of the operating status and the provisional determination of the provisional current in the third embodiment will be described. In the power receiving device 1 of the third embodiment, a specific value of the printing frequency in the time period when charging of the battery 63 starts, which is the operating status, is identified. The specific value is identified based on the number of times printing is performed in each time period (number of prints), which is the first operating status, and the time when the power receiving device 1 is connected to the power supply device 99 when charging the battery 63 (connection start time), which is the second operating status.

[0091] The power receiving device 1 of the third embodiment identifies a specific value related to the number of sheets printed per charge of the battery 63 based on a time zone counter 73 (see FIG. 12) (P3, see FIG. 4). The time zone counter 73 is stored in the flash memory 54. The time zone counter 73 counts the number of prints in each time zone of a day, which is the first operating status. In the third embodiment, the time zones are divided into three-hour intervals, such as 0:00 to 3:00, 3:00 to 6:00, 6:00 to 9:00, ..., 18:00 to 21:00, and 21:00 to 24:00. The time zone counter 73 stores the total number of prints and the printing frequency derived from the total number and the number of prints counted in each time zone.

[0092] The power receiving device 1 acquires the connection start time, which is the second operating status, based on the clock 41. The power receiving device 1 classifies the connection start time into the corresponding time slot in the time slot counter 73. The power receiving device 1 identifies the printing frequency of the time slot into which the connection start time is classified, among the time slots in the time slot counter 73, as a specific value. For example, if the connection start time is 5:00 PM, the power receiving device 1 identifies 32.7% as the specific value.

[0093] The power receiving device 1 provisionally determines the power receiving current based on the detected USB standard operation mode of the power supply device 99, the specific value determined from the operating status, and a third power receiving determination table 83 (see FIG. 13) (P4, see FIG. 4). The third power receiving determination table 83 is stored in the ROM 52. For example, if the USB standard operation mode of the power supply device 99 is the USB Type-C (3 A) standard and the specific value of the determined operating status is 32.7%, the power receiving device 1 provisionally determines the power receiving current to be 3.0 A. In the third power receiving determination table 83, the lower the printing frequency in the time period into which the connection start time falls, the smaller the current provisionally determined to be within the range of current that can be output in the USB standard operation mode as the power receiving current.

[0094] <Third power reception processing> 14, the second power receiving process executed by the CPU 51 will be described. The third power receiving process is a process in which the power receiving device 1 receives power from the power supply device 99 based on the printing frequency in the time period into which the connection start time is classified as the operating status of the power receiving device 1. At the start of the third power receiving process, the FETs 32 and 62 and the switch 35 are all in the OFF state. When the power supply device 99 is connected to the USB connector 91 via the cable 98, the CPU 51 reads out a program stored in the ROM 52 and executes the third power receiving process.

[0095] When the third power receiving process is started, the CPU 51 acquires the connection start time based on the clock 41 (S41). The CPU 51 detects the USB standard operation mode of the power supply device 99 (S2). The CPU 51 determines the power receiving voltage (S3).

[0096] The CPU 51 executes a first time period classification process (S42). In the first time period classification process, the CPU 51 classifies the connection start time acquired in S41 into the corresponding time period in the time period counter 73 (see FIG. 12).

[0097] The CPU 51 executes a third identification process (S43). In the third identification process, the CPU 51 identifies, as a specific value, the printing frequency of the time period into which the connection start time is classified among the time periods in the time period counter 73. The CPU 51 provisionally determines the receiving current based on the detected USB standard operating mode of the power supply device 99, the specific value identified in S43, and a third power receiving determination table 83 (see FIG. 13) stored in the ROM 52 (S5).

[0098] The CPU 51 determines whether the receiving current provisionally determined in S5 is 0.5 A (S6). If the provisionally determined receiving current is 0.5 A (S6: YES), the CPU 51 shifts the process to S10. If the provisionally determined receiving current exceeds 0.5 A (S6: NO), the CPU 51 executes a load test (S7). The CPU 51 determines whether the load test executed in S7 is passed (S8). If the load test is judged to be passed (S8: YES), the CPU 51 shifts the process to S10. If the load test is judged to be failed (S8: NO), the CPU 51 subtracts 0.5 A from the provisionally determined receiving current and sets the result as the receiving current (S9). The CPU 51 returns the process to the judgment of S6.

[0099] The CPU 51 determines the receiving current (S10). The CPU 51 notifies the power supply device 99 of the receiving power corresponding to the determined combination of the receiving voltage and receiving current (S11). The power supply device 99 outputs the power notified by the power receiving device 1 to the power receiving device 1. The CPU 51 turns on the switch 35 and the FET 62 to start supplying the receiving power to the battery 63 (S12). The CPU 51 ends the third power receiving process.

[0100] <Second printing process> The second printing process executed by the CPU 51 will be described with reference to Figure 15. The second printing process is a process in which the power receiving device 1 of the third embodiment prints on a print medium using the print head 21. When the second printing process starts, the power receiving device 1 and the power supply device 99 are not connected via the cable 98, and the FETs 32 and 62 and the switch 35 are all in the OFF state. When the user operates the input unit 5 and issues a command to execute the second printing process, the CPU 51 reads out a program stored in the ROM 52 and executes the second printing process.

[0101] When the second print process is started, the CPU 51 acquires the time when the second print process is started (print start time) based on the clock 41 (S51). The CPU 51 executes a second time zone classification process (S52). In the second time zone classification process, the CPU 51 classifies the print start time acquired in S51 into the corresponding time zone in the time zone counter 73 (see FIG. 12).

[0102] The CPU 51 updates the time zone counter 73 (S53). In updating the time zone counter 73, the CPU 51 adds 1 to the counter value corresponding to the time zone into which the print start time was classified in S52. The CPU 51 adds 1 to the total number of prints on the print medium. The CPU 51 derives the printing frequency from the total number of prints and the counter value for each time zone. The CPU 51 stores the updated time zone counter 73, including the counter value for each time zone, the total number of prints, and the printing frequency for each time zone, in the flash memory 54.

[0103] The CPU 51 executes the printing process (S37). In the printing process, the CPU 51 drives the transport motor 11 and the print head 21 to transport the printing medium and print on the number of sheets of printing medium acquired in S34.

[0104] <Actions and Effects of Third Embodiment> In the power receiving device 1 of the third embodiment, the CPU 51 acquires the connection start time when charging the battery 63 (S41). The CPU 51 executes a third identification process (S43). In the third identification process, the CPU 51 identifies, as a specific value, the printing frequency in the time period into which the connection start time is classified, based on the connection start time as the second operating status. In this way, the printing frequency in the time period in which charging of the battery 63 is started, which is identified as a specific value of the operating status, is based on the number of times of printing in each time period, which is the first operating status, and the connection start time, which is the second operating status. Therefore, the power receiving device 1 can receive appropriate power based on the two operating statuses.

[0105] The power receiving device 1 defines the number of prints in each time period as a first operating status and the connection start time as a second operating status. In the third power receiving process, the power receiving device 1 executes a first time period classification process and classifies the connection start time into the corresponding time period in the time period counter 73 (S42). In the third identification process, the CPU 51 sets the printing frequency in the time period into which the connection start time is classified as a specific value (S43). This allows the power receiving device 1 to charge the battery with appropriate power according to the printing frequency in the time period to which the power supply device 99 is connected.

[0106] The printing frequency in a time period into which the connection start time, which is a specific value of the operating status, is classified decreases as the number of times printing occurs in the time period into which the connection start time is classified. In the third power receiving determination table 83, the lower the printing frequency in a time period into which the connection start time is classified, the smaller the current determined as the receiving current within the range of current that can be output in the USB standard operating mode. In other words, the lower the number of times printing occurs in a time period into which the connection start time is classified, the smaller the current determined as the receiving current within the range of current that can be output in the USB standard operating mode. If the power supply device 99 is connected during a time period in which the number of times printing occurs is low, the user is unlikely to print using the power receiving device 1 during that time period. Therefore, the power receiving device 1 can sufficiently charge the battery 63 without causing heat generation with a small amount of received power.

[0107] <Modification of the third embodiment> The second embodiment is not limited to the above and can be modified in various ways. The first operating status in the third embodiment may be related to the amount of printing that the print head 21 has done on the print medium. For example, the operating status in the second embodiment may be the number of pages that have been printed on the print medium by the print head 21. The first operating status may also be the number of times the first printing process has been performed per charge of the battery 63.

[0108] <Modifications of the First to Third Embodiments> The present invention is not limited to the first to third embodiments described above, and various modifications are possible. The configuration of the power receiving device 1 may be modified as appropriate. For example, the power receiving device 1 may not include a battery 63. In this case, the power receiving device 1 receives power from the power supply device 99 according to the operating status, and drives the print head 21 with the received power to perform printing. The power receiving device 1 may not include a print head 21. In this case, the power receiving device 1 drives the carry motor 11 and the like with power from the battery 63.

[0109] In the first to third embodiments, the power receiving device 1 and the power supply device 99 are connected via a cable 98, which is a USB cable, but the power receiving device 1 only needs to determine the received power within the range of power that the power supply device 99 can supply, and is not limited to power transmission based on the USB standard.

[0110] The operating status is not limited to those in the first to third embodiments. For example, the operating status may be the time when the power receiving device 1 is turned on after one charge of the battery 63.

[0111] In the first to third embodiments, the current value subtracted from the provisionally determined receiving current in the process of S9 is not limited to 0.5 A. Furthermore, the current value subtracted from the provisionally determined receiving current in the process of S9 does not have to be the same every time. For example, in the first embodiment, the amount subtracted from the provisionally determined receiving voltage when it is determined that the load test has failed may be the current immediately to the left of the current corresponding to the identified connection time in the first power receiving determination table 81.

[0112] In the first to third embodiments, the CPU 51 determines the receiving voltage based on the detected USB standard operating mode. Alternatively, the CPU 51 may tentatively determine the receiving voltage based on the detected USB standard operating mode. In this case, the CPU 51 may change the tentatively determined receiving voltage based on a specific value of the operating condition. Furthermore, when changing the receiving voltage based on a specific value of the operating condition, the CPU 51 does not need to determine the receiving power based on the specific value of the operating condition. In other words, the CPU 51 may determine at least one of the receiving voltage and receiving current that determine the receiving power based on the specific value of the operating condition.

[0113] In the first to third embodiments, the CPU 51 determines the receiving current by referring to the first power receiving determination table 81, the second power receiving determination table 82, or the third power receiving determination table 83 stored in the ROM 52 based on the USB standard operation mode of the power supply device 99 detected via the cable 98 and a specific value determined from the operating status. Alternatively, the CPU 51 may calculate the receiving current using a formula based on the USB standard operation mode and the specific value determined from the operating status. For example, in the first embodiment, the receiving current I may be determined by calculating it from the formula I=W / (V·t) using the amount of power W required to fully charge the battery 63, the receiving voltage V determined from the USB standard operation mode, and the connection time t determined from the operating status. In this case, the power receiving device 1 can receive more appropriate power depending on the operating status.

[0114] The steps of the first power receiving process, the second power receiving process, the third power receiving process, the first printing process, and the second printing process are not limited to being executed by the CPU 51. Some or all of the steps of the first power receiving process, the second power receiving process, the third power receiving process, the first printing process, and the second printing process may be executed by another electronic device (e.g., an ASIC). The steps of the first power receiving process, the second power receiving process, the third power receiving process, the first printing process, and the second printing process may be distributed and processed by multiple electronic devices (e.g., multiple CPUs). The scope of the present invention also includes an embodiment in which an operating system (OS) running on the power receiving device 1 executes some or all of the steps of the first power receiving process, the second power receiving process, the third power receiving process, the first printing process, and the second printing process based on instructions from the CPU 51.

[0115] The programs for executing the first power receiving process, the second power receiving process, the third power receiving process, the first printing process, and the second printing process may be downloaded (i.e., transmitted as a transmission signal) from a server connected to a network (not shown), and stored in the flash memory 54. In this case, the programs for executing the first power receiving process, the second power receiving process, the third power receiving process, the first printing process, and the second printing process may be stored in a non-transitory storage medium such as an HDD provided in the server.

[0116] <Other> In the above embodiment, the flash memory 54 is an example of a "storage unit" of the present invention. The processing of S2 is an example of a "detection means" of the present invention. The processing of S4, S24, and S43 is an example of a "situation identification means" of the present invention. The processing of S5 to S10 is an example of a "detection means" of the present invention. The battery 63 is an example of a "cell" of the present invention. The processing of S15 is an example of a "time classification means" of the present invention. The processing of S16 is an example of a "time counting means" of the present invention. The print head 21 is an example of a "printing unit" of the present invention. The number of printed sheets is an example of a "first printing amount" of the present invention. The sheet number category is an example of a "quantity category" of the present invention. The processing of S35 is an example of a "quantity classification means" of the present invention. The processing of S36 is an example of a "quantity counting means" of the present invention. The processing of S41 is an example of an "acquisition means" of the present invention. The number of prints is an example of a "second printing amount" of the present invention. The processing of S42 is an example of a "time period identification means" of the present invention. The first power receiving determination table 81, the second power receiving determination table 82, and the third power receiving determination table 83 are examples of the "database" of the present invention. The ROM 52 is an example of the "second memory unit" of the present invention. The processing of S5 is an example of the "provisional determination means" of the present invention. The voltage drop is an example of the "loss" of the present invention. The processing of S7 is an example of the "loss identification means" of the present invention. The judgment of S8 is an example of the "judgment means" of the present invention. The processing of S9 is an example of the "main determination means" of the present invention. [Explanation of symbols]

[0117] 1 Power receiving device 21 Print head 41 Clock 51 CPU 54 Flash Memory 63 Battery 91 USB connector 98 Cable 99 Power Supply Equipment

Claims

1. A power receiving device that determines and receives power within a range of power supply capacity that indicates power that can be supplied by a power supply device, a storage unit that stores a first operating status that is a past operating status of the power receiving device; a detection means for detecting the power supply capacity of the power supply device; a status specifying means for specifying a specific value relating to the first operating status from the storage unit; a determination means for determining the received power based on the power supply capability detected by the detection means and the specific value specified by the situation specification means; a battery that is charged by the power received from the power supply device; a printing unit that is driven by the power charged in the battery and prints an image on a medium; Equipped with The power receiving device, wherein the first operating condition is a first print volume printed by the printing unit using power from the battery charged in a single charge.

2. A power receiving device that determines and receives power within a range of power supply capacity that indicates the power that can be supplied by a power supply device, a storage unit that stores a first operating status that is a past operating status of the power receiving device; a detection means for detecting the power supply capacity of the power supply device; a status specifying means for specifying a specific value relating to the first operating status from the storage unit; a determination means for determining the received power based on the power supply capability detected by the detection means and the specific value specified by the situation specification means; a battery that is charged by the received power received from the power supply device; Equipped with the first operating condition is a connection time between the battery and the power supply device during a single charge of the battery; a time classification means for classifying the connection times stored in the storage unit into time segments determined by the lengths of the connection times; a time counting means for counting the number of times the connection time is classified into each of the time segments by the time classification means; Further provided with The power receiving device, wherein the situation specifying means specifies, as the specific value, the connection time in the time segment in which the number of times counted by the time counting means is the greatest.

3. A power receiving device that determines and receives power within a range of power supply capacity that indicates the power that can be supplied by a power supply device, a storage unit that stores a first operating status that is a past operating status of the power receiving device; a detection means for detecting the power supply capacity of the power supply device; a status specifying means for specifying a specific value relating to the first operating status from the storage unit; a determination means for determining the received power based on the power supply capability detected by the detection means and the specific value specified by the situation specification means; a battery that is charged by the received power received from the power supply device; Equipped with the first operating condition is a connection time between the battery and the power supply device during a single charge of the battery; The power receiving device, wherein the situation specifying means specifies an average value of the connection time stored in the storage unit as the specified value.

4. The power receiving device according to claim 2 or 3, wherein the determining means determines a smaller power within the range of the power supply capacity as the received power, the larger the specific value related to the connection time identified by the situation identifying means.

5. The power receiving device according to claim 1, characterized in that the determination means determines a smaller power within the range of the power supply capacity as the received power, the smaller the specific value for the first printing volume identified by the situation identification means.

6. an amount classification means for classifying the first printing amount stored in the storage unit into amount classes that are classified according to the size of the first printing amount; an amount counting means for counting the number of times the first printing amount is classified into each of the amount categories by the amount classifying means; Equipped with The situation specifying means specifies the first printing amount in the amount category that has been counted the most times by the amount counting means as the specified value. The power receiving device according to claim 1 or 5,

7. 7. The power receiving device according to claim 1, wherein the condition specifying unit specifies the average value of the first print volume stored in the storage unit as the specified value.

8. 8. The power receiving device according to claim 1, wherein the situation specifying unit specifies the maximum value of the first printing amount stored in the storage unit as the specified value.

9. A power receiving device that determines and receives power within a range of power supply capacity that indicates power that can be supplied by a power supply device, a storage unit that stores a first operating status that is a past operating status of the power receiving device; a detection means for detecting the power supply capacity of the power supply device; a status specifying means for specifying a specific value relating to the first operating status from the storage unit; a determination means for determining the received power based on the power supply capability detected by the detection means and the specific value specified by the situation specification means; an acquisition means for acquiring a second operating status which is a current operating status of the power receiving device; The power receiving device, wherein the condition specifying means specifies the specific value based on the second operating condition acquired by the acquiring means.

10. a battery that is charged by the power received from the power supply device; a printing unit that is driven by the power charged in the battery and prints an image on a medium; Equipped with the first operating status is a second print volume printed by the printing unit in each time period in a day using the power of the charged battery, The second operating status is a connection start time of the current connection with the power supply device for charging the battery, the power receiving device includes a time zone specification unit that specifies to which time zone the connection start time acquired by the acquisition unit corresponds; The situation specifying unit specifies the second print volume for the time period specified by the time period specifying unit as the specified value. The power receiving device according to claim 9 .

11. The power receiving device according to claim 10 , wherein the determining unit determines, as the second print volume identified by the situation identifying unit is smaller, a smaller amount of power within the range of the power supply capacity as the received power.

12. A power receiving device that determines and receives power within a range of power supply capacity that indicates power that can be supplied by a power supply device, a storage unit that stores a first operating status that is a past operating status of the power receiving device; a detection means for detecting the power supply capacity of the power supply device; a status specifying means for specifying a specific value relating to the first operating status from the storage unit; a determination means for determining the received power based on the power supply capability detected by the detection means and the specific value specified by the situation specification means; The power receiving device, wherein the determining means determines the received power by performing calculations based on the power supply capability detected by the detecting means and the specific value identified by the situation identifying means.

13. A power receiving device that determines and receives power within a range of power supply capacity that indicates power that can be supplied by a power supply device, a storage unit that stores a first operating status that is a past operating status of the power receiving device; a detection means for detecting the power supply capacity of the power supply device; a status specifying means for specifying a specific value relating to the first operating status from the storage unit; a determination means for determining the received power based on the power supply capability detected by the detection means and the specific value specified by the situation specification means; a second storage unit that stores a database indicating a relationship between the power supply capability, the specific value, and the received power; The power receiving device is characterized in that the determination means determines the received power by referring to the database stored in the second memory unit from the power supply capacity detected by the detection means and the specific value identified by the situation identification means.

14. A power receiving device that determines and receives power within a range of power supply capacity that indicates power that can be supplied by a power supply device, a storage unit that stores a first operating status that is a past operating status of the power receiving device; a detection means for detecting the power supply capacity of the power supply device; a status specifying means for specifying a specific value relating to the first operating status from the storage unit; a determination means for determining the received power based on the power supply capability detected by the detection means and the specific value specified by the situation specification means; Equipped with The determining means a provisional determination means for determining a provisional received power, which is the provisional received power, based on the power supply capacity detected by the detection means and the specific value specified by the situation specification means; a loss specifying means for specifying a loss that will occur when the temporary received power determined by the temporary determination means is received from the power supply device; a determination means for determining whether the loss identified by the loss identification means is equal to or greater than a predetermined threshold; a final determination means for determining, when the determination means determines that the loss exceeds a predetermined threshold, a power smaller than the provisional received power determined by the provisional determination means as the received power; A power receiving device comprising:

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