Tag reading device

Abstract

The present invention discloses a tag reading device, which provides a reading process of an RFID tag while suppressing a temperature rise. According to an embodiment, the tag reading device has an antenna, a communication control circuit, a temperature measuring device, a data storage device, and a processor. The communication control circuit controls an output signal output from the antenna and a signal received by the antenna. The temperature measuring device measures the temperature inside a body. The data storage device stores a set value for an output value of an output signal corresponding to a temperature detected by the temperature measuring device. The processor sets the output value of the output signal corresponding to the temperature detected by the temperature measuring device to the communication control circuit according to the set value stored in the data storage device, and performs reading of an RFID tag using the communication control circuit and the antenna.

Description

[0001] This application claims priority from Japanese patent application No. JP2020-029096, filed on February 25, 2020, and cites the contents of the above application, the disclosure of which is hereby incorporated by reference in its entirety. Technical Field

[0002] An embodiment of the present invention relates to a tag reading device. Background Art

[0003] When a tag reading device continuously and repeatedly performs the reading process of an RFID tag (hereinafter, also referred to as a wireless tag), the temperature of the body will rise. When the temperature of the body rises and exceeds the allowable temperature of a component, the tag reading device may malfunction. In order to prevent malfunctions caused by temperature rise, existing tag reading devices sometimes stop operation when a predetermined critical temperature such as the allowable temperature of a component is reached to prevent the temperature from rising.

[0004] However, if the tag reading device suddenly stops due to an unexpected temperature rise during the continuous reading of the RFID tag, the reading rate will be greatly reduced. For example, in a tag reading system, the tag reading device is moved while the result obtained by continuously reading the RFID tag is used to perform processing such as searching for the RFID tag or identifying the object. In such a tag reading system, if the tag reading device suddenly stops due to an unexpected temperature rise, there is a problem that the expected processing result expected by the operator cannot be obtained. Summary of the invention

[0005] In order to solve the above-mentioned problem, an object of the present invention is to provide a tag reading device capable of performing a reading process of an RFID tag while suppressing a temperature rise.

[0006] According to an embodiment, a tag reading device includes an antenna, a communication control circuit, a temperature measuring device, a data memory, and a processor. The communication control circuit controls an output signal output from the antenna and a signal received by the antenna. The temperature measuring device measures the temperature inside the body. The data memory stores a set value for an output value of an output signal corresponding to the temperature detected by the temperature measuring device. The processor sets the output value of the output signal corresponding to the temperature detected by the temperature measuring device to the communication control circuit according to the set value stored in the data memory, and performs reading of an RFID tag using the communication control circuit and the antenna.

[0007] According to the above-mentioned tag reading device, it is possible to perform a reading process by adjusting the output value of the output signal while measuring the temperature change.

[0008] In the above-mentioned tag reading device, the processor further sets an interval at which the communication control circuit outputs the output signal from the antenna based on the temperature measured by the temperature measuring device together with the output value.

[0009] According to the above-mentioned tag reading device, the output interval of the output signal can be adjusted while measuring the temperature change.

[0010] In the above-mentioned tag reading device, the data memory stores step-by-step setting values ​​for multiple temperature ranges specified by multiple thresholds, and the processor sets the output value of the output signal based on the setting value for the temperature range stored in the data memory, including the temperature detected by the temperature measuring device.

[0011] According to the above-mentioned tag reading device, the output value of the output signal can be adjusted according to the temperature range.

[0012] The tag reading device described above also includes a communication interface for communicating with a host device, wherein the data storage device stores setting values ​​for each action mode, and the processor sets the output value of the output signal based on the setting value corresponding to the action mode specified by the host device.

[0013] According to the above-mentioned tag reading device, the output value can be set according to the operation mode.

[0014] In the above-mentioned tag reading device, which has a communication interface for communicating with a host device, the processor sends information indicating the output value of the output signal to the host device together with tag information of the RFID tag read using the communication control circuit and the antenna.

[0015] According to the above-mentioned tag reading device, the output value can be sent to the host device, so the host device can detect the tag.

[0016] Another aspect of the present invention is a tag reading device comprising: an antenna; a communication control circuit that controls an output signal output from the antenna and a signal containing tag information of an RFID tag received by the antenna; a temperature meter that measures the temperature inside a body; an output setting unit that sets an output value of the output signal; and a processor that causes the output value of the output setting unit to decrease in a stepwise manner according to a rise in the temperature measured by the temperature meter.

[0017] According to the above-described tag reading device, it is possible to provide a tag reading device that performs a reading process of an RFID tag while suppressing a temperature rise.

[0018] The tag reading device described above also includes a communication interface for communicating with a host device, and the processor sends information indicating the output value of the output signal to the host device together with tag information of the RFID tag read using the communication control circuit and the antenna.

[0019] According to the above-mentioned tag reading device, the output value can be sent to the host device, so the host device can detect the tag.

[0020] In the above-mentioned tag reading device, the processor further sends the RSSI value to the host device based on the tag information of the RFID tag and the output value of the output signal.

[0021] According to the above-mentioned tag reading device, the RSSI value can be transmitted to the host device, so that the host device can detect the movement of the tag.

[0022] The tag reading device further includes a time timer for outputting a next output signal after stopping the output of the output signal, and the processor extends the time measured by the timer stepwise according to the increase in the temperature measured by the temperature measuring device.

[0023] According to the above-mentioned tag reading device, the temperature rise can be further suppressed.

[0024] Another aspect of the present invention is a tag reading device comprising: an antenna; a communication control circuit that controls an output signal output from the antenna and a signal received by the antenna; a temperature meter that measures the temperature inside a body; a timer that measures the time to output the next output signal after stopping the output of the output signal; and a processor that extends the time measured by the timer in a step-by-step manner according to the increase in temperature measured by the temperature meter.

[0025] According to the above-described tag reading device, it is possible to provide a tag reading device that performs a reading process of an RFID tag while suppressing a temperature increase. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A block diagram schematically shows a configuration example of a tag reading system including a tag reading device according to an embodiment.

[0027] Figure 2 It is a diagram showing a first application example of the tag reading system in the embodiment.

[0028] Figure 3 It is a diagram showing a second application example of the tag reading system in the embodiment.

[0029] Figure 4It is a diagram showing a configuration example of a setting table stored in a data memory of a tag reading device in an embodiment.

[0030] Figure 5 This is a flowchart for explaining an example of the operation of the tag reading device in the embodiment.

[0031] Description of Reference Numerals

[0032] 1(101, 201)…Tag reading system

[0033] 10 (110, 210) ... tag reading device

[0034] 11(111, 211)…upper device

[0035] 21…Processor

[0036] 24…Communication control circuit

[0037] 25…Antenna

[0038] 26…Communication interface

[0039] 29…Data storage

[0040] 30…Timer

[0041] 46…Output setting unit

[0042] 48…Thermistor (temperature measuring device). DETAILED DESCRIPTION

[0043] Hereinafter, embodiments will be described with reference to the drawings.

[0044] First, the configuration of the tag reading device 10 and the tag reading system 1 including the tag reading device 10 according to the embodiment will be described.

[0045] Figure 1 It is a block diagram schematically showing a configuration example of a tag reading system 1 including a tag reading device 10 according to the embodiment.

[0046] like Figure 1 As shown, the tag reading system 1 in the embodiment includes a tag reading device 10 and a host device 11. In the tag reading system 1, the tag reading device 10 reads an RFID tag (wireless tag). The host device 11 estimates the position of the RFID tag or identifies the item with the read RFID tag based on the result obtained by the tag reading device 10 continuously reading the RFID tag.

[0047] For example, the tag reading system is applied as a search system for searching for items with RFID tags located in a predetermined area such as a warehouse or a store. In the tag reading system 1 as such a search system, the tag reading device 10 continuously reads the RFID tag while moving the tag reading device 10 relative to the RFID tag. The host device 11 obtains the reading result of the RFID tag from the tag reading device, and detects the change in the relative position of the tag reading device and the RFID tag based on the obtained reading result. The reading result of the RFID tag also includes information indicating the strength of the received signal received by the tag reading device from the RFID tag. The host device 11 detects the change in the relative position of the tag reading device and the RFID tag based on the change in the strength of the received signal arranged in time order.

[0048] In addition, in the present embodiment, the tag reading device 10 is moved while continuously reading the RFID tags attached to articles such as commodities. The host device 11 performs predetermined processing (search processing, article reading processing) based on the reading results of the continuously read RFID tags. However, the tag reading system 1 may also be: a tag reading device set at a predetermined position continuously reads the RFID tags attached to the moving articles.

[0049] The tag reading device 10 receives a response signal from an RFID tag within the communication range through wireless communication, thereby reading the information recorded in the RFID tag. For example, the tag reading device may be a portable device that an operator operates manually, or may be mounted on a mobile object.

[0050] The tag reading device 10 sends an electric wave requesting a response to the RFID tag at a set intensity (output value). The tag reading device 10 receives a response signal from the RFID tag corresponding to the electric wave requesting a response. The tag reading device 10 receives a response signal indicating tag information from an RFID tag (an RFID tag activated by the emitted electric wave) within the communication range. In addition, if there are multiple RFID tags within the communication range, the tag reading device receives response signals indicating the tag information of each of these RFID tags.

[0051] In addition, the tag reading device 10 measures the RSSI value indicating the strength of the response signal (received signal) received from the RFID tag. The tag reading device 10 may also provide the tag information contained in the response signal from the RFID tag together with the RSSI value as the reading result of the RFID tag to the host device 11. In addition, the tag reading device 10 may also send the output value when the response signal is received in the reading result of the RFID tag to the host device 11.

[0052] The RFID tag is attached to an article such as a commodity or a component, and the tag information containing information identifying the article is recorded in the internal memory. The RFID tag is activated by the radio wave from the tag reading device 10. The RFID tag outputs a response signal according to the read command from the tag reading device 10, and the response signal contains the tag information recorded in its own memory. The RFID tag operates according to the radio wave (output signal) from the tag reading device 10. Therefore, the strength of the response signal output by the RFID tag is also affected by the strength (output value) of the radio wave emitted from the tag reading device 10.

[0053] The host device 11 is an information processing terminal having a function of communicating with the tag reading device 10. For example, the host device 11 is an information processing terminal such as a smartphone or a tablet PC having a display device with a touch screen as a user interface. In addition, the host device 11 may also have a communication interface capable of communicating with the tag reading device, or may be an information processing device set at a specific location.

[0054] exist Figure 1 In the illustrated configuration example, the host device 11 includes a processor 12 , a memory 13 , a communication interface (I / F) 14 , a display 15 , an input device 16 , and the like.

[0055] The processor 12 performs control of each part and data processing. The processor 12 is, for example, a CPU. In the host device 11, the processor 12 executes the program stored in the memory 13, thereby realizing various actions. For example, the processor 12 detects the movement of the RFID tag or the change in the relative position between the tag reading device 10 and the RFID tag based on the reading result of the RFID tag obtained from the tag reading device 10. These processes are realized by the processor 12 executing the application program installed in the memory 13.

[0056] The communication I / F 14 is an interface for communicating with an external device. In the present embodiment, the communication I / F 14 is an interface for communicating with the tag reading device 10. The communication I / F 14 may be a device corresponding to the communication function of the tag reading device 10. The communication I / F 14 may be an interface for wired communication or an interface for wireless communication. For example, the communication I / F 14 is implemented by a LAN interface, a USB (Universal Serial Bus) interface, a Bluetooth (registered trademark) interface, or a Wifi interface.

[0057] The display 15 is a device for displaying information. For example, the display 15 displays the detection result of the RFID tag (for example, the movement of the RFID tag), etc. The input device 16 is a device for the operator to input operation instructions, etc. The display 15 and the input device 16 are composed of, for example, a display device with a touch screen.

[0058] Next, the structure of the tag reading device 10 in the embodiment will be described.

[0059] exist Figure 1 In the illustrated configuration example, the tag reading device 10 includes a processor 21 , a ROM 22 , a RAM 23 , a communication control circuit 24 , an antenna 25 , a communication interface (I / F) 26 , a display 27 , a power supply 28 , a data storage 29 , and a timer 30 .

[0060] The processor 21 controls each part. The processor 21 includes, for example, a CPU or other computing circuit. The processor 21 executes a program to control each part and perform various data processing. In addition, the processor 21 may also have an internal memory. The processor 21 executes a program stored in the ROM 22 or the internal memory to perform various processing. For example, the processor 21 interprets the instruction received from the host device 11 by the communication I / F 26 and performs processing corresponding to the instruction.

[0061] ROM 22 is a non-volatile memory that cannot be rewritten. ROM 22 stores programs executed by processor 21, etc. RAM 23 is a volatile memory that temporarily stores data. For example, RAM 23 functions as a working memory or a buffer memory. RAM 23 has a buffer memory that stores the reading results of RFID tags.

[0062] The communication control circuit 24 and the antenna 25 constitute an RFID interface for reading RFID tags.

[0063] The communication control circuit 24 includes a control circuit for communicating with the RFID tag via the antenna 25. The communication control circuit 24 transmits the transmission signal (radio wave) supplied from the processor 21 from the antenna 25 at a set output value. The antenna 25 outputs the transmission signal supplied from the communication control circuit 24 as a radio wave that the RFID tag can receive.

[0064] In addition, the communication control circuit 24 not only outputs the transmission signal to the antenna 25, but also provides the signal received by the antenna 25 as reception data to the processor 21. That is, the antenna 25 receives the response signal from the RFID tag, and the communication control circuit 24 processes the response signal (reception signal) received by the antenna 25 and provides it to the processor 21. For example, the communication control circuit 24 provides the processor 21 with the tag information contained in the reception signal from the RFID tag and the RSSI value indicating the strength of the reception signal.

[0065] The communication I / F 26 is an interface for communicating with an external device. In the tag reading system 1, the communication I / F 26 is a communication interface for communicating with the host device 11. The communication I / F 26 can be an interface for communication connection with the host device 11. The communication I / F 26 can be an interface for wired communication or an interface for wireless communication. For example, the communication I / F 26 is implemented by a LAN interface, a USB (Universal Serial Bus) interface, a Bluetooth (registered trademark) interface, or a Wifi interface.

[0066] The display 27 is a display device for displaying the operating state of the RFID tag. The display 27 is composed of, for example, an LED or the like.

[0067] The power supply 28 provides power for operating the tag reading device 10. The power supply 28 provides power for operation to each part of the tag reading device 10. For example, if the tag reading device is a portable device, the power supply 28 is implemented by a rechargeable battery. In addition, if the tag reading device is a desktop device that can be connected to a commercial power supply, the power supply 28 is composed of a power supply circuit connected to the commercial power supply.

[0068] The data memory 29 is a rewritable nonvolatile memory. The data memory 29 stores setting values ​​for various processes. The setting values ​​stored in the data memory 29 are, for example, information that can be updated according to the application mode. The data memory 29 can also store application programs. In addition, the data memory 29 can also store information such as processing results that should be retained even after the power is turned off.

[0069] The timer 30 measures time. The timer 30 measures the elapsed time according to the control from the processor 21. For example, the timer 30 measures the elapsed time from the stop of the reading action (output of the output signal) to the start of the next reading action (output of the next output signal). The processor 21 starts the reading action when the reading interval (rest time) is reached, wherein the reading interval is set by the elapsed time from the stop of the reading action to the start of the next reading action measured by the timer 30.

[0070] In addition, Figure 1 In the structural example shown, the communication control circuit 24 has a modulation unit (modulation circuit) 41, a transmitting side amplifier (amplifier circuit) 42, a directional coupler (coupler) 43, a receiving side amplifier (amplifier circuit) 44, a demodulation unit (demodulation circuit) 45, an output setting unit (output level setting circuit) 46, a level detection unit (receiving level detection circuit) 47 and a thermistor 48, etc.

[0071] The modulation unit 41 is a modulation circuit that modulates a waveform signal (carrier) according to input data. The modulation unit 41 modulates the carrier according to the transmission data sent from the processor 21. The transmission side amplifier 42 is an amplifier circuit that amplifies the input signal. The transmission side amplifier 42 amplifies the output signal of the modulation unit 41. The directional coupler 43 includes a circuit that provides the output signal of the transmission side amplifier 42 to the antenna 25. As a result, the communication control circuit 24 outputs the carrier modulated according to the transmission data from the antenna 25.

[0072] The RFID tag receives the radio waves transmitted from the antenna 25. The RFID tag recognizes, for example, a read command included in the signal received from the antenna 25. When recognizing the read command, the RFID tag outputs the data (tag information) stored in its own memory as radio waves, for example, by backscatter modulation.

[0073] The antenna 25 receives the radio waves output by the RFID tag. The directional coupler 43 includes a circuit that obtains the received signal received by the antenna 25 and provides the obtained received signal to the receiving side amplifier 44. The receiving side amplifier 44 is an amplifier circuit that amplifies the input signal. The receiving side amplifier 44 amplifies the received signal received by the antenna 25. The demodulator 45 is a demodulator circuit that demodulates the data superimposed on the waveform signal (carrier). The demodulator 45 demodulates the data (tag information) contained in the received signal amplified by the receiving side amplifier 44.

[0074] The antenna 25 can be a device for transmitting and receiving radio waves, wherein the radio waves are transmitted and received between the antenna 25 and the RFID tag. That is, the antenna 25 sends a signal provided to the RFID tag and receives the radio waves output by the RFID tag. In the present embodiment, the antenna 25 is configured to send electromagnetic waves to the reading area. The tag reading device 10 is configured to communicate with the RFID tags attached to all the commodities arranged in the reading area via the antenna 25. The antenna 25 is, for example, a planar antenna. However, the antenna 25 is not limited to a specific structure.

[0075] The output setting unit 46 is a setting circuit for setting the intensity (output value) of the signal to be output. The output setting unit 46 controls so that the intensity of the signal output to the amplifier 42 becomes the set output value. The amplifier 42 amplifies the signal provided from the modulator 41 to the output value set by the output setting unit 46, and outputs it to the coupler 43. Thus, the antenna 25 transmits the output signal (radio wave) of the output value set by the output setting unit 46 and provided from the amplifier 42 via the coupler 43.

[0076] The level detection unit 47 is a level detection circuit that detects (measures) the strength of a signal. The level detection unit 47 detects the strength of a signal input to the receiving side amplifier 44. The reception signal received by the antenna 25 is input to the receiving side amplifier 44 via the coupler 43. That is, the level detection unit 47 is configured to detect an RSSI value indicating the strength of the reception signal (response signal from the RFID tag) received by the antenna 25.

[0077] The thermistor 48 is a temperature measuring device (temperature measuring device). The thermistor 48 measures the temperature inside the machine body. For example, the thermistor 48 detects the temperature on a substrate that is disposed inside the machine body and forms the communication control circuit 24. The thermistor 48 provides information indicating the detected temperature to the processor 21. The processor 21 performs operation control such as communication control based on the temperature detected by the thermistor 48.

[0078] Next, an application example of the tag reading system 1 in the embodiment will be described.

[0079] First, a first application example of the tag reading system 1 in the embodiment will be described.

[0080] Figure 2 This is a diagram for explaining a configuration example of an RFID tag search system 101 as a first application example of the tag reading system 1 in the embodiment.

[0081] The search system 101 as the tag reading system 1 is a system for searching for a specific RFID tag (RFID tag attached to a specific product) T in the search area R. For example, when searching for a specific product in a warehouse or a store, the search system 101 estimates the location of the RFID tag attached to the product based on the reading result of the RFID tag T obtained by the tag reading device 110. The search system 101 displays the estimated location of the RFID tag and notifies the operator of the location. Thus, the search system 101 can assist the operator in finding the specific product.

[0082] As Figure 2 The search system 101 of the tag reading system 1 shown includes a portable tag reading device 110 and a host device 111 connected to the tag reading device 110. Figure 2 In the structural example shown, the tag reading device 110 is Figure 1 In the modified example of the tag reading device 10 shown in FIG. 1 , the host device 111 is Figure 1 A modified example of the host device 11 is shown.

[0083] Figure 2 The tag reading device 110 shown in FIG. Figure 1The control system shown in the figure has a gripping unit 121 gripped by an operator and a holding unit 122 holding a host device 111. The tag reading device 110 is set in the holding unit 122, and the operator grips the gripping unit 121 to operate. For example, the operator moves the tag reading device 110, changes the communication range (RFID tag reading range) R, and searches in the search area until the desired RFID tag T is detected.

[0084] In addition, the host device 111 has Figure 1 The control system shown in the figure has a display device with a touch screen as a display 15 and an input device 16. For example, the host device 111 is implemented by a portable information terminal such as a smartphone or a tablet PC. The host device 111 notifies the operator of the position of the RFID tag T estimated based on the reading result of the RFID tag obtained by the tag reading device 110.

[0085] In the search system 101, the operator moves the tag reading device 110 in a state where the host device 111 is installed by hand, thereby searching for RFID tags T. In the search system 101, the tag reading device 110 reads RFID tags at a predetermined reading interval within the communication range R that changes due to the movement of the operator. The tag reading device 110 provides the host device 111 with the reading results of the RFID tags within the communication range that changes according to the operation of the operator. The tag reading device 110 provides (transmits) the tag information (ID) such as EPC, the RSSI value of the received signal, and the output value during the reading action as the reading results of each RFID tag to the host device 111.

[0086] The host device 111 detects the desired reading result of the RFID tag from the tag reader 110 based on the reading result of the RFID tag T. The host device 111 estimates the position of the RFID tag T based on the desired reading result of the RFID tag T. For example, the host device 111 detects the position of the RFID tag T or the change in the relative position between the tag reader 110 and the RFID tag based on the RSSI value or the like included in the reading result of the RFID tag. The strength (RSSI value) of the signal received by the tag reader 110 from the RFID tag T changes due to the change in the strength (output value) of the radio wave output by the tag reader 110. Therefore, the host device 111 obtains the output value when the tag reader 110 reads the RFID tag T, and estimates the position of the RFID tag T based on the change in the RSSI value based on the output value. The host device 111 displays information indicating the position of the RFID tag T estimated based on the reading result of the RFID tag T on the display device 131 with a touch screen.

[0087] Next, a second application example of the tag reading system 1 in the embodiment will be described.

[0088] Figure 3 1 is a diagram showing a configuration example of an article reading system (inventory counting system) 201 as a second application example of the tag reading system 1 in the embodiment.

[0089] The article reading system 201 of the tag reading system 1 is a system for reading the RFID tags T attached to articles (goods) placed at predetermined locations such as shelves. For example, the article reading system 201 is a system for determining the goods present at predetermined locations by reading the RFID tags T attached to each good at predetermined locations such as shelves. For example, during inventory operations, an operator can read the RFID tags T attached to each good at a shelf through the tag reading device 210, thereby determining the goods present at the shelf.

[0090] As Figure 3 The article reading system 201 of the tag reading system 1 shown includes a portable tag reading device 210 and a host device 211 connected to the tag reading device 210. Figure 3 In the structural example shown, the tag reading device 210 is Figure 1 In the modified example of the tag reading device 10 shown in FIG. 1 , the host device 211 is Figure 1 A modified example of the host device 11 is shown.

[0091] The tag reading device 210 and the host device 211 can be Figure 2 The tag reading device 110 shown in FIG. 1 has the same structure as the host device 111. Figure 1 The control system shown in FIG. 1 includes a gripping unit 221 gripped by an operator and a holding unit 122 holding a host device 211. In addition, the host device 111 includes Figure 1 The control system shown in the figure is configured to include a display device with a touch panel as a display 15 and an input device 16. For example, the host device 111 is implemented by a portable information terminal such as a smartphone or a tablet PC.

[0092] In the article reading system 201, the operator holding the gripping portion 221 operates the tag reading device 210 in a state where the host device 211 is set on the holding portion 222. For example, the operator moves the tag reading device 210 in the following manner: within the communication range (RFID tag reading range) R of the tag reading device 210, thereby reading the entire shelf.

[0093] In the article reading system 201, the tag reading device 210 reads the RFID tag T located in the communication range R that changes due to the movement of the operator at a predetermined reading interval. The tag reading device 210 provides the reading results of the RFID tags in the communication range R that changes according to the operation of the operator to the host device 211. The tag reading device 210 provides the tag information (ID) such as EPC and the output value during the reading operation as the reading results of each RFID tag T to the host device 211.

[0094] The host device 211 determines the items with the RFID tag T read based on the reading results of each RFID tag T obtained from the tag reading device 210. The host device 211 determines the items with the RFID tag T based on the tag information of the read RFID tag T. In addition, the host device 211 can also be configured to: determine information indicating how many of a certain type of commodity there are based on the serial number inherent to each RFID tag T contained in the tag information. The host device 211 can display information indicating the items determined based on the reading results of the RFID tag T in the display device 131 with a touch screen. In addition, the host device 211 can also provide information indicating the items determined based on the reading results of each RFID tag T to a higher-level device (such as a management server).

[0095] In addition, the search system as the first application example and the article reading system as the second application example can be implemented by the same hardware structure. Therefore, the search system 101 as the first application example and the article reading system as the second application example can also be implemented by mode switching. For example, the host device 11 (111, 211) can also make the tag reading device 10 (110, 210) operate in the mode specified by the operator.

[0096] Next, the setting information stored in the data memory 29 of the tag reading device 10 will be described. Figure 4 1 is a diagram showing a configuration example of a setting table 51 and a setting table 52 indicating setting values ​​set so that the tag reading device 10 in the embodiment performs a reading operation according to the internal temperature of the device.

[0097] exist Figure 4 In the example shown, a first setting table 51 corresponding to the first operation mode and a second setting table 52 corresponding to the second operation mode are stored in the data memory 29. The setting table 51 and the setting table 52 are stored in the data memory 29. The setting table 51 and the setting table 52 stored in the data memory 29 may be updateable. In addition, a new setting table corresponding to a new operation condition (e.g., an operation mode) may be added to the data memory 29.

[0098] Figure 4The first setting table 51 and the second setting table 52 shown have the same structure but different setting values. However, the plurality of setting tables stored in the data memory 29 may have different structures.

[0099] exist Figure 4 In the illustrated configuration example, the setting tables 51 and 52 set output values ​​P and rest time D for each temperature range defined by a plurality of threshold values ​​for temperature a. Temperature a is the temperature inside the tag reading device 10. In the present embodiment, temperature a is the temperature measured by the thermistor 48. The output value P represents a set value for the magnitude of the output signal (radio wave) output from the antenna 25. The rest time D is a set value for the interval (reading interval) of the continuously executed reading action of the RFID tag.

[0100] The first setting table 51 shows the setting values ​​of the output value P and the rest time D in the first operation mode. In the first setting table 51, the output value and the rest time are set corresponding to the three threshold values ​​th11, th12, and th13 for the temperature a. Here, regarding the three threshold values ​​th11, th12, and th13, it is assumed that the first threshold value th11<the second threshold value th12<the third threshold value th13.

[0101] For example, when the temperature a is below the first threshold value th11, the output value P is set to the initial value (standard value) p10, and the rest time D is set to the initial value (standard value) d10. When the temperature a is below the first threshold value th11, the temperature in the tag reading device 10 is a normal value (a temperature that does not require temperature suppression control), and the output value P and the rest time D are set to the standard setting values.

[0102] When the temperature a is greater than the first threshold value th11 and less than the second threshold value th12, the output value P is set to a value obtained by subtracting the first output adjustment value p11 from the initial value (standard value) p10. In this case, the rest time D is set to a value obtained by adding the first time adjustment value d11 to the initial value (standard value) d10.

[0103] When the temperature a is greater than the first threshold value th12 and less than the third threshold value th13, the output value P is set to a value obtained by subtracting the first output adjustment value p11 and the second output adjustment value p12 from the initial value (standard value) p10. In this case, the rest time D is set to a value obtained by adding the first time adjustment value d11 and the second time adjustment value d12 to the initial value (standard value) d10.

[0104] Thus, as the temperature a increases, the output value P decreases stepwise. As the temperature a increases, the rest time D increases stepwise.

[0105] When the temperature a is greater than the third threshold value th13, the RFID tag reading operation becomes an error. That is, when the temperature a is greater than the third threshold value th13, the temperature in the tag reading device 10 is an abnormal value that cannot be operated, and the RFID tag reading operation is stopped (prohibited).

[0106] In addition, the second setting table 52 shows the setting values ​​of the output value P and the rest time D in the second operation mode different from the first operation mode. In the second setting table 52, the output value P and the rest time D are set corresponding to the three threshold values ​​th21, th22, and th23 for the temperature a. Here, the three threshold values ​​th21, th22, and th23 are set to the first threshold value th21<the second threshold value th22<the third threshold value th23. In addition, the three threshold values ​​th21, th22, and th23 may be the same value as the threshold values ​​th11, th12, and th23, or may be different values.

[0107] For example, when the temperature a is below the first threshold value th21, the output value P is set to the initial value (standard value) p20, and the rest time D is set to the initial value (standard value) d20. When the temperature a is below th21, the temperature in the tag reading device 10 is a normal value (a temperature that does not require temperature suppression control), and the output value P and the rest time D are set to the standard setting values.

[0108] When the temperature a is greater than the first threshold value th21 and less than the second threshold value th22, the output value P is set to a value obtained by subtracting the first output adjustment value p21 from the initial value (standard value) p20. In this case, the rest time D is set to a value obtained by adding the first time adjustment value d21 to the initial value (standard value) d20.

[0109] When the temperature a is greater than the second threshold value th22 and less than the third threshold value th23, the output value P is set to a value obtained by subtracting the first output adjustment value p21 and the second output adjustment value p22 from the initial value (standard value) p20. In this case, the rest time D is set to a value obtained by adding the first time adjustment value d21 and the second time adjustment value d22 to the initial value (standard value) d20.

[0110] When the temperature a is greater than the third threshold th23, the RFID tag reading operation becomes an error. That is, when the temperature a is greater than the third threshold th23, the temperature in the tag reading device 10 becomes an abnormal value that cannot be operated, and the RFID tag reading operation is stopped (prohibited).

[0111] In addition, the output adjustment values ​​p21 and p22 of the second setting table 52 may be the same as or different from the output adjustment values ​​p11 and p12 of the first setting table 51. In addition, the time adjustment values ​​d21 and d22 of the second setting table 52 may be the same as or different from the time adjustment values ​​d11 and d12 of the first setting table 51. In addition, any of the output adjustment values ​​p11, p12, p21, p22 or the time adjustment values ​​d11, d12, d21, d22 may be "0".

[0112] like Figure 4 As shown in the figure, in the setting table, each action mode can be set. For example, in the action mode that prioritizes maintaining the reading interval, it can be set to prioritize reducing the output value and suppressing the extension of the rest time in response to the temperature rise. In addition, in the action mode that prioritizes maintaining the output value (communication range), it can be set to prioritize reducing the decrease in the output value and prioritize extending the rest time in response to the temperature rise.

[0113] For example, in the search system described as the first application example, the location of the RFID tag is unknown. Therefore, when the action mode is the search system, the setting of increasing the reading interval and maintaining the priority output value (without reducing the communication range) is considered. As a result, the following action setting can be achieved: the RFID tag attached to the item can be searched while maintaining the search range in a wide range.

[0114] In the article reading system described as the second application example, the reading target area (e.g., shelf) is determined, but it is required to reliably read the RFID tags located in the reading target area. Therefore, in the case where the action mode is the article reading system, the following setting is considered: in response to the temperature rise, the output value is reduced, and the maintenance of the reading interval is prioritized (the reading interval is not increased). As a result, the following action setting can be achieved: even if the operator causes the tag reading device to operate quickly, the RFID tags attached to the articles located in the reading target area such as the shelf can be reliably read.

[0115] Next, the operation of the tag reading device 10 in the embodiment will be described.

[0116] Figure 5 This is a flowchart for explaining an example of the operation of the tag reading device 10 in the embodiment.

[0117] The processor 21 of the tag reading device 10 starts the continuous reading process (search process, article reading process) of the RFID tag in response to a request from the host device 11 connected via the communication I / F 26. When the processor 21 starts reading the RFID tag, it obtains the temperature a detected by the thermistor 48 (ACT 10). In addition, when the reading starts, the processor 21 starts measuring the elapsed time t using the timer 30 (ACT 12).

[0118] In addition, when starting to read, the processor 21 sets the output value P and the reading interval D to the standard value (initial value) (ACT11). The output value P and the reading interval D are stored in the register provided in the RAM 23. That is, the processor 21 sets the output value P stored in the register to the standard value p0 (p10, p20), and sets the reading interval D to the standard value d0 (d10, d20). Therefore, in ACT11, P = p0 (p10, p20), and D = d0 (d10, d20).

[0119] After acquiring the temperature a, the processor 21 determines a setting table corresponding to the operation mode for setting the output value P and the reading interval D. After determining the setting table corresponding to the operation mode, the processor 21 compares the temperature a with the first threshold th1 (th11, th21) of the setting table (ACT13).

[0120] When the temperature a is equal to or lower than the first threshold value th1 (th11, th21) in the setting table (ACT13, No), the process proceeds to ACT19.

[0121] When the temperature a is greater than the first threshold value th1 of the setting table (ACT13, yes), the processor 21 updates the output value P and the reading interval D according to the setting table (ACT14). That is, the processor 21 subtracts the output adjustment value p1 (p11, p21) from the output value P stored in the register, thereby P=p0-p1. In addition, the processor 21 adds the time adjustment value d1 (d11, d21) to the reading interval D stored in the register, thereby D=d0+d1.

[0122] After comparing the temperature a with the first threshold th1 (th11, th21) of the setting table, the processor 21 compares the temperature a with the second threshold th2 (th12, th22) of the setting table (ACT 15).

[0123] When the temperature a is lower than the second threshold value th2 of the setting table (ACT 15, No), the processor 21 determines the output value P and the reading interval D stored in the register and proceeds to ACT 19. That is, when the first threshold value th1 < a ≤ the second threshold value th2, the output value P is P = p0-p1, and the reading interval D is D = d0+d1.

[0124] When the temperature a is greater than the second threshold th2 (th12, th22) of the setting table (ACT15, yes), the processor 21 updates the output value P and the reading interval D according to the setting table (ACT16). That is, when the second threshold th2 < a, the processor 21 further subtracts the output adjustment value p2 (p12, p22) from the output value P (p0-p1) stored in the register, thereby P = p0-p1-p2. In addition, when the second threshold th2 < a, the processor 21 adds the time adjustment value d2 (d12, d22) to the reading interval D (d0+d1) stored in the register, thereby D = d0+d1+d2.

[0125] After comparing the temperature a with the second threshold th2 (th12, th22) of the setting table, the processor 21 compares the temperature a with the third threshold th3 (th13, th23) of the setting table (ACT 17).

[0126] When the temperature a is lower than the third threshold th3 of the setting table (ACT 17, YES), the processor 21 proceeds to ACT 19. That is, when the second threshold th2 < a ≤ the third threshold th3, the output value P is P = p0-p1-p2, and the reading interval D is D = d0+d1+d2.

[0127] In addition, when the temperature a is greater than the third threshold value th3 (ACT17, No), the processor 21 performs error processing (ACT18) according to the setting table. That is, when the third threshold value th3 < a, the processor 21 stops the reading action and performs error processing. As an error processing, the processor 21 displays the error condition through the display 27. In addition, the processor 21 can also notify the upper device 11 of the situation where the reading action is stopped due to the increase in the temperature of the body. In addition, when the temperature a is greater than the third threshold value th3 (ACT17, No), the processor 21 enters ACT22 and waits for the temperature to drop. However, when the temperature a is greater than the third threshold value th3, the processor 21 can also stop the continuous reading process and forcibly end a series of processes.

[0128] After determining the output value P and the reading interval D, the processor 21 determines whether the elapsed time t reaches the reading interval D (ACT19). When the elapsed time t reaches the reading interval D (ACT19, yes), the processor 21 issues an output signal through the output value P determined according to the temperature, thereby executing the RFID tag reading action (ACT20) (the processor 21 and the timer 30 are linked to each other to extend the rest time stepwise according to the increase in temperature. That is, the timer 30 extends the measurement time).

[0129] As a reading action of the RFID tag, the processor 21 specifies the output value P determined according to the temperature to the output setting unit 46 of the communication control circuit 24, so that the output signal output from the antenna 25 is the output value P (the output setting unit 46 reduces the output value stepwise according to the increase in temperature based on the specification of the processor 21). After specifying the output value, the processor 21 uses the communication control circuit 24 to send the output signal containing the read command from the antenna 25 at the specified output value. For example, the communication control circuit 24 generates a modulated signal that modulates the carrier with the read command through the modulation unit 41. The transmitting side amplifier 42 amplifies the modulated signal from the modulation unit 41 to the output value set by the output setting unit 46. The modulated signal amplified by the amplifier 42 to the set output value is provided to the antenna 25 via the directional coupler 43. As a result, the antenna 25 sends the output signal representing the read command as an electric wave of the set output value.

[0130] The RFID tag existing in the reading area to which the output signal from the antenna 25 is transmitted is activated by receiving the output signal from the antenna 25 and recognizes the read command. The RFID tag that recognizes the read command transmits a response signal, for example, by backscatter modulation, and the response signal includes the tag information stored in its own memory.

[0131] The antenna 25 receives a response signal representing tag information from the RFID tag. The signal received by the antenna 25 is provided to the receiving side amplifier 44 via the directional coupler 43. The received signal amplified by the amplifier 44 is input to the demodulator 45, and a signal representing tag information of the RFID tag is demodulated. The signal demodulated by the demodulator 45 is provided to the processor 21 as tag information (ID) read from the RFID tag.

[0132] In addition, the received signal input to the receiving side amplifier 44 (the response signal received by the antenna 25 from the RFID tag) is also input to the level detection unit 47. The level detection unit 47 measures the strength of the received signal and provides the RSSI value indicating the measured strength of the received signal to the processor 21. Thus, the processor 21 obtains the tag information (ID) of the RFID tag provided from the demodulation unit 45 and the RSSI value of the received signal from the RFID tag as the reading result of the RFID tag.

[0133] The processor 21 stores the tag information and RSSI value obtained through the communication control circuit 24 and the antenna 25 in correspondence with the output value in the buffer memory provided in the RAM 23. Thus, each time an RFID tag is read, the tag information (ID), RSSI value, and output value are stored in the buffer memory as a set of RFID tag reading results.

[0134] During the execution of the reading operation, the processor 21 determines whether the first reading operation is stopped (ACT21). If it is determined that the first reading operation is stopped (ACT21, yes), the processor 21 temporarily stops the reading operation (ACT22) and determines whether to end the continuous reading (ACT23). For example, if the processor 21 determines that an instruction requesting the end is received from the host device 11, the continuous reading process is ended.

[0135] If the continuous reading is not completed, that is, if the next reading operation is to be performed (ACT 23, No), the processor 21 returns to ACT 10 and performs the above operation again. Thus, the processor 21 repeatedly performs the RFID tag reading operation until it is determined that the continuous reading is completed.

[0136] In addition, when the continuous reading is finished (ACT23, yes), the processor 21 sends the reading result of the RFID tag stored in the buffer memory set in the RAM 23 to the host device 11 (ACT24). The processor 21 sends the reading result of the RFID tag to the host device 11, wherein the reading result of the RFID tag includes the tag information, RSSI value and output value of the RFID tag as a set of information. However, the information sent to the host device can be determined according to the operation mode. For example, the tag information corresponding to the output value can be sent to the host device 11, or only the tag information can be sent.

[0137] The host device 11 obtains the result of reading the RFID tag at the reading interval set according to the temperature as the time-sequential RFID tag reading result through the communication I / F 14. The processor 12 of the host device 11 performs processing such as estimating the position of a specific RFID tag or identifying an item with an RFID tag based on the RFID tag reading result obtained from the tag reading device 10 through the communication I / F 14. For example, the host device 11 can also estimate the position where the RFID tag exists based on the communication range (reading range) based on the output value included in the reading result of the RFID tag.

[0138] According to the above-mentioned operation example, the tag reading device in the embodiment sets the output value of the output signal output from the antenna according to the temperature in the device. In addition, the tag reading device adjusts the reading interval of the RFID tag according to the temperature in the device. Thus, the tag reading device can suppress the temperature rise in the device and prevent the components in the device from being damaged due to high temperature.

[0139] In addition, the tag reading device in the embodiment maintains setting information corresponding to the operation mode, and sets the output value and reading interval set according to the temperature based on the setting information corresponding to the operation mode. Thus, the tag reading device can set the control for suppressing the temperature rise according to the operation mode as the tag reading system, and can suppress the temperature rise in a manner that can obtain a reading result matching the operation mode.

[0140] In addition, although the case where the output value P is decreased stepwise as the temperature rises is given as an example, it is also possible to increase the output value P when the temperature rises. When there is still a margin between the temperature exceeding th13 and th23, the output value P can be increased even if the temperature rises. It is possible to temporarily read RFID tags in a wider range. In addition, although the case where the rest time D is extended as the temperature rises is given as an example, it is also possible to shorten the rest time D when the temperature rises. When there is still a margin between the temperature exceeding th13 and th23, the rest time D can be shortened even if the temperature rises. It is possible to temporarily read RFID tags in a shorter period of time.

[0141] In addition, the data storage device 29 may also be provided in the cloud.

[0142] In addition, in the above-mentioned embodiment, the case where the program executed by the processor is pre-stored in the memory in the device is described. However, the program executed by the processor can also be downloaded from the network to the device, or installed from a storage medium to the device. The storage medium can be a storage medium that can store programs and can be read by the device. In addition, the functions obtained by pre-installation or downloading can also be realized by cooperating with the OS (operating system) etc. inside the device.

[0143] Several embodiments of the present invention have been described, but these embodiments are only provided as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the scope of the invention. These embodiments or their variations are included in the scope or gist of the invention, and are included in the invention described in the claims and their equivalents.

Claims

1. A label reading device, characterized in that: have: antenna; a communication control circuit that controls an output signal output from the antenna and a signal received by the antenna; A temperature measuring device for measuring the temperature inside the machine body; a data memory storing a set value for an output value of the output signal corresponding to the temperature detected by the temperature measuring device and data indicating that a reading operation is stopped; as well as a processor that sets an output value of the output signal corresponding to the temperature detected by the temperature measuring device to the communication control circuit according to the set value stored in the data memory, and executes reading of the RFID tag using the communication control circuit and the antenna, The data memory stores setting values ​​for a plurality of temperature ranges defined by a first threshold, a second threshold greater than the first threshold, and a third threshold greater than the second threshold. When a reference value is stored as a set value below a first threshold value, and the second threshold value has a margin to a third threshold value, when the temperature range is greater than the first threshold value and less than the second threshold value, a value higher than the reference value is stored; when the temperature range is greater than the second threshold value and less than the third threshold value, a value lower than the reference value is stored; and when the temperature is greater than the third threshold value, data indicating that the reading action is stopped is stored.

2. The tag reading device according to claim 1, wherein: The processor further sets an interval at which the communication control circuit outputs the output signal from the antenna based on the temperature measured by the temperature measuring device together with the output value.

3. The tag reading device according to claim 1 or 2, wherein: It has a communication interface for communicating with the host device. The data memory stores setting values ​​for each action mode. The processor sets an output value of the output signal based on a setting value corresponding to an operation mode designated by the host device.

4. The tag reading device according to claim 1 or 2, wherein: The tag reading device also has a communication interface for communicating with a host device. The processor transmits information indicating an output value of the output signal together with tag information of the RFID tag read by using the communication control circuit and the antenna to the host device.

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