JP5201422B2 - Wireless tag communication device - Google Patents

Description

  The present invention relates to a wireless tag communication device that transmits and receives information to and from a wireless tag by wireless communication.

  Conventionally, a wireless tag communication device for improving communication performance with a wireless tag provided on an object housed in a box or the like has already been disclosed (for example, see Patent Document 1).

  In this prior art, a plurality of objects to which wireless tags are respectively attached are stored in a storage container such as a box, and the storage container is placed on a rotary table. Around the turntable, a plurality of antennas for the RFID tag reader are provided in different directions, up, down, left and right. When the turntable on which the storage container is placed rotates in the horizontal direction, the direction of the tag antenna of the wireless tag attached to each object changes in the horizontal plane. As a result, the direction of the tag antenna matches one of the plurality of antennas of the wireless tag reading device during the rotation. Thereby, when the match is established, the wireless tag reader can reliably read information from the wireless tag.

JP 2009-223480 A

  In the above prior art, when the positional relationship between the device antenna of the wireless tag communication device and the tag antenna of the wireless tag is not suitable for wireless communication, the information reading performance of the wireless tag communication device is improved by improving the positional relationship. improves. However, since the device antenna located outside the storage container is configured to communicate with the wireless tag inside the storage container, there is a limit to improving the information reading performance from a plurality of wireless tags inside the storage container. there were. In addition, when communication is attempted with the device antenna close to the storage container or a plurality of wireless tags in the storage container, there are a plurality of wireless tags, storage containers, etc. in the immediate vicinity of the device antenna. The deviation of the impedance of the antenna cannot be ignored. The above prior art does not consider such an impedance shift, and it is difficult to improve the information reading performance in that sense.

  An object of the present invention is to provide a wireless tag communication device capable of reliably performing smooth wireless communication with a plurality of wireless tags in a storage container and improving information reading performance.

  In order to achieve the above object, the first invention is configured in a substantially linear shape so that it can be inserted into a predetermined storage container, and is connected to the device antenna for wireless communication with a wireless tag. A main body housing provided with a communication circuit for performing predetermined processing relating to wireless communication, and provided at an end portion of the main body housing, the device antenna is placed in a first position and an upright position that stand upright with respect to the main body housing Switching support means for supporting switching to a substantially orthogonal second position, insertion detection means for detecting a state in which the device antenna is inserted into the predetermined storage container, and the insertion A detection means for determining whether or not the state in which the device antenna is inserted into the predetermined storage container is detected, and depending on the determination result of the insertion determination means, the device amplifier And having a matching means for matching controlling the impedance of Na.

  The wireless tag communication device according to the first aspect of the present invention includes a main body housing, a device antenna, and switching support means. The device antenna is configured in a substantially linear shape, and can be switched to either the first position or the second position via the switching support means.

  In the first position, the device antenna stands upright with respect to the main body housing. In the first position, the device antenna is used by being inserted into a predetermined storage container in which a plurality of wireless tags are arranged. The electromagnetic wave radiation direction from the substantially linear device antenna is a direction orthogonal to the axis. Therefore, in the first position, electromagnetic waves are radiated toward the periphery of the device antenna inserted in the storage container. Thus, the wireless tag communication device can perform wireless communication with the plurality of wireless tags present around the device antenna in the storage container.

  In the second position, the device antenna is in a direction orthogonal to the first position, in other words, a direction along the main body housing. As described above, the electromagnetic wave radiation direction from the substantially linear device antenna is a direction orthogonal to the axis. Therefore, in this second position, the device antenna can radiate electromagnetic waves in a direction linearly away from the main body housing. As a result, the wireless tag communication device can perform wireless communication with a wireless tag that is remote from the device.

  On the other hand, when the device antenna performs wireless communication with a plurality of wireless tags in the storage container as described above, since there are a plurality of wireless tags, storage containers, etc. in the immediate vicinity of the device antenna, the impedance of the device antenna is reduced. The deviation cannot be ignored. Therefore, in the first invention of the present application, an insertion detection means for detecting the insertion state of the device antenna is provided, and the insertion determination means determines whether the inserted state is detected by the insertion detection means. Then, according to the determination result, the matching unit performs matching control on the impedance of the device antenna. Accordingly, when the device antenna is inserted into the storage container and wireless communication is performed with respect to a plurality of wireless tags, the impedance of the device antenna can be set to a value suitable for the communication state at a short distance.

  As described above, according to the first invention of the present application, the operator can insert the device antenna into the storage container, and the impedance of the device antenna is adjusted to a suitable value by the insertion. Therefore, wireless communication can be smoothly performed with respect to a plurality of wireless tags in the storage container, and information reading performance can be improved. In addition, the operator can perform wireless communication with a wireless tag away from the device by switching the device antenna from the first position to the second position.

  According to a second aspect of the present invention, in the first aspect, the device antenna is configured to have a variable axial length, and includes a length detection unit that detects the axial length of the device antenna, and the matching unit. Is characterized by matching the impedance of the device antenna in accordance with the axial length of the device antenna detected by the length detection means.

  By making the axial length of the device antenna variable, even when electromagnetic waves of a plurality of types of frequencies are used, it is possible to easily realize an antenna length suitable for the wavelength corresponding to each frequency. At this time, the electrical length of the antenna changes as the axial length of the device antenna changes, but the matching means tracks the change in electrical length by matching the impedance according to the axial length. Impedance values can be reliably matched.

  According to a third invention, in the first or second invention, the device antenna is moved to the second position by the switching detection means for detecting a state in which the device antenna is switched to the second position, and the switch detection means. Switching determining means for determining whether a switched state is detected, wherein the matching means performs matching control of impedance of the device antenna according to a determination result of the switching determination means. To do.

  As described above, when wireless communication is performed with respect to a wireless tag that is remote from the device, the deviation of the impedance of the device antenna is not a problem. On the other hand, when the device antenna performs wireless communication with a plurality of wireless tags in the storage container, a deviation in impedance of the device antenna cannot be ignored. Accordingly, in the third invention of the present application, a switching detection means for detecting that the device antenna has been switched to the second position is provided. Then, the switching determination unit determines whether or not the switching state to the second position is detected, and the matching unit performs matching control of the impedance of the apparatus antenna according to the determination result. Thus, when the device antenna is not switched to the second position and remains in the first position, the impedance of the device antenna can be set to a value for short-range communication. As a result, when the operator inserts the device antenna into the storage container as the first position, the impedance of the device antenna is reliably adjusted to a value suitable for short-range communication. On the other hand, smooth wireless communication can be reliably performed.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, there is provided a communication instruction unit that allows an operator to instruct the start of wireless communication, and the switching determination unit causes the switching detection unit to switch the device antenna to the second position. When it is determined that it has not been detected, and the insertion determination unit determines that the insertion detection unit has not detected the state in which the device antenna is inserted into the predetermined storage container, the communication Instruction determining means for determining whether or not the wireless communication start instruction is issued by the instruction means; and notification means for performing a predetermined warning notification when the instruction determining means determines that the wireless communication start instruction is received. It is characterized by having.

  As described above, in the first position, the device antenna is in a state suitable for short-range communication to the wireless tag in the storage container. Therefore, it is not preferable that wireless communication is performed without being inserted into the storage container even though the device antenna is in the first position because the communication characteristics of the device antenna do not match. Therefore, in the fourth invention of the present application, the instruction determination means determines whether or not the communication instruction means gives an instruction to start wireless communication when the operator erroneously operates in the state as described above, and the determination is satisfied. In the case of notification, the notification means performs a predetermined warning notification. Thereby, it can be made to recognize reliably that it is said state with respect to an operator.

  In a fifth aspect of the present invention based on any one of the first to fourth aspects, the device antenna has a width-direction dimension or a thickness-direction dimension of a tip portion larger than a width-direction dimension or a thickness-direction size other than the tip portion. It is configured to be small.

  Thus, even when a large number of articles provided with wireless tags are packed in the storage container, the operator can easily and smoothly insert the device antenna into the storage container.

  According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the insertion determination unit determines that the insertion detection unit has detected the insertion state of the device antenna into the predetermined storage container. In this case, the apparatus has a communication control means for controlling to start wireless communication by the device antenna.

  Thus, when the operator inserts the device antenna into the storage container, no separate operation is required, and wireless communication by the device antenna is started. As a result, the operation burden on the operator can be reduced and the convenience can be improved.

  A seventh invention is characterized in that, in any one of the first to sixth inventions, there is provided a grip portion which is located at a lower portion of the main body casing and can be gripped by an operator.

  Accordingly, the portable wireless tag communication device can smoothly perform wireless communication with respect to a plurality of wireless tags in the storage container, and can also perform wireless communication with respect to the wireless tag that is remote from the device.

  According to the present invention, smooth wireless communication can be reliably performed with a plurality of wireless tags in a storage container, and communication performance can be improved.

It is a perspective view which shows the operation | movement aspect of the reader which is embodiment of the radio | wireless tag communication apparatus of this invention. It is explanatory drawing which shows the usage condition of a reader. It is a functional block diagram which shows the functional structure of a reader. It is a flowchart which shows the control procedure performed at the time of radio | wireless communication. It is a flowchart which shows the detailed procedure of step S100 in FIG. It is a flowchart which shows the control procedure performed in the modification which starts communication without a trigger when insertion of an apparatus antenna is detected. It is a top view which shows the operation | movement aspect of the apparatus antenna in the modification which comprised the axial direction length variably. It is a block diagram which shows the functional structure of the reader in the case of the apparatus antenna in the modification which comprised the axial direction length variably. It is a perspective view which shows the operation | movement aspect of the apparatus antenna in the modification which is a dipole antenna. It is explanatory drawing which shows the reader | leader in the case of the modification made into the stationary type.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1A, a portable reader 1 that is a wireless tag communication device of the present embodiment includes a gun-type reader body 10 and a personal information terminal that is a portable information terminal attached to the reader body 10. And Digital Assistant (hereinafter referred to as “PDA”) 30. The reader main body 10 includes a rectangular tube-shaped main body housing 2 that includes various communication circuits (see FIG. 3 described later) that perform predetermined processing related to wireless communication. A handle 3 as a gripping part that can be gripped and communicated by an operator is provided on one side in the longitudinal direction of the main body housing 2, that is, on the lower part on the rear end side.

  On the upper surface of the main body housing 2, an attaching / detaching portion 4 for detachably attaching the PDA 30 is provided. A device antenna 50 and a proximity sensor 22 as insertion detection means are provided on the other side in the longitudinal direction of the main housing 2, that is, on the front end. The PDA 30 includes a slot 31 whose front end is open. An electronic medium 32 such as an SD memory card is inserted into the slot 31 so that it can be inserted and removed.

  The handle 3 includes a trigger switch 6 as communication instruction means. The trigger switch 6 is used for instructing start or stop of wireless communication with the wireless tag T.

  In this example, the device antenna 50 is formed of a tapered rectangular tube-shaped conductor having a tip width direction dimension smaller than the other width direction dimensions. This device antenna is a λ / 4 monopole antenna having a length corresponding to a quarter of the frequency λ and grounded at one end.

  The device antenna 50 is rotatably attached to an antenna support 51 provided as a switching support means also serving as a power feeding unit provided at the front end of the main body housing 2. Thereby, when the operator rotates the device antenna 50 by hand, the device antenna 50 is positioned at the first position in FIG. On the other hand, it can be switched to the second position in FIG. 1B, which is bent in the lateral direction and is substantially orthogonal to the upright position.

  An example of a usage state when the device antenna 50 is switched to the first position is shown in FIG. In FIG. 2A, a plurality of articles to which the wireless tags T are attached are stored in the storage container 40. In this case, the communication function of the reader 1 is set for short-distance communication, which will be described later, and the device antenna 50 in an upright state with respect to the main body housing 2 is inserted into the storage container 40 in which the plurality of wireless tags T are arranged. And used. At this time, the device antenna 50 can be easily inserted into the storage container 40 due to the tapered shape. In addition, you may provide a stopper so that it may not bend in the middle of insertion. Further, the device antenna 50 is not limited to a tapered rectangular tube shape. That is, other shapes may be used as long as the width direction dimension or the thickness direction dimension of the tip portion is smaller than the width direction dimension or the thickness direction dimension other than the tip portion.

  In addition, the electromagnetic wave radiation direction from the device antenna 50 is a direction orthogonal to the axis of the device antenna 50 when inserted into the storage container 40. Therefore, electromagnetic waves are radiated from the device antenna 50 inserted into the storage container 40 toward the periphery of the device antenna 50, and the reader 1 is connected to a plurality of short-range wireless devices existing around the device antenna 50 in the storage container 40. Wireless communication with the tag T can be reliably performed.

  The device antenna 50 can be inserted into the storage container 40 by using a notch 41 for a handle provided on the opposite side surface of the storage container 40 or a gap between the upper lid 42 of the storage container 40. it can.

  On the other hand, FIG. 2B shows an example of the usage state when the device antenna 50 is switched to the second position. In FIG. 2B, the reader 1 in this case has a communication function set for long-distance communication, and performs wireless communication with a plurality of wireless tags T separated from the reader 1. In this case, since the electromagnetic wave radiation direction from the device antenna 50 is orthogonal to the axis of the device antenna 50, the device antenna 50 bent in a lateral direction with respect to the main body housing 2 is straight from the main body housing 2. Radiate electromagnetic waves in a direction away from the target. Accordingly, the reader 1 can perform wireless communication with a plurality of wireless tags T separated from the reader 1.

  Returning to FIG. 1A and FIG. 1B, a known bending sensor 23 (see FIG. 3 described later) such as a load cell is built in the antenna support portion 51 as a switching detection means. When the device antenna 50 switched to the first position rotates, the bending sensor 23 is turned on, thereby detecting that the device antenna 50 has been switched from the first position to the second position.

  The proximity sensor 22 is a push-type mechanical sensor or an optical sensor. The proximity sensor 22 indicates that the device antenna 50 in the state of being switched to the first position is inserted into the storage container 40, or the push button is pressed against the side wall of the storage container 40 or the storage container for irradiated light. It is detected by a change in the amount of light reflected by the 40 side walls.

  The reader body 10 and the PDA 30 are connected to each other so as to be able to transmit and receive information via a cable 20 (see FIG. 3) such as a universal serial bus (USB) cable. The connection between the reader body 10 and the PDA 30 is not limited to a wired cable, and may be a wireless connection such as Bluetooth.

  Next, the functional configuration of the reader 1 will be described with reference to FIG.

  In FIG. 3, the reader main body 10 of the reader 1 includes the trigger switch 6, the device antenna 50, the communication control unit 11, the control circuit 12, the transmission circuit 15, the reception circuit 16, and the antenna duplexer 17. The proximity sensor 22, the bending sensor 23, and a matching mechanism 26 as a matching means are provided.

  The communication control unit 11 controls information communication performed between the PDA 30 and the cable 20.

  The control circuit 12 includes a CPU and a memory such as a ROM and a RAM (not shown). The control circuit 12 controls the entire operation of the reader body 10 by executing a program stored in advance in the ROM while using the temporary storage function of the RAM.

  The transmission circuit 15 and the reception circuit 16 access the RFID tag circuit section To of the RFID tag T existing in the predetermined communication range S via the device antenna 50, and perform transmission / reception of information. As described above with reference to FIGS. 2A and 2B, the communication range S includes not only long-distance communication with the wireless tag T located away from the device antenna 50 but also the device antenna 50. It is a communicable range including short-distance communication with the surrounding wireless tag T. The transmission circuit 15 and the reception circuit 16 are connected to the antenna duplexer 17, and the antenna duplexer 17 is connected to the device antenna 50 via the matching mechanism 26.

  The wireless tag circuit unit To includes a tag antenna 151 and an IC circuit unit 150. The tag antenna 151 transmits and receives information. The IC circuit unit 150 includes a memory unit (not shown) that stores information.

  The matching mechanism 26 uses the impedance matching circuit 27a for short-distance communication, the impedance matching circuit 27b for long-distance communication, and the switching control signal from the control circuit 12 to connect the impedance matching circuit 27a or 27b to the antenna duplexer 17 and the device. A pair of circuit changeover switches 28 that operate in conjunction with each other are provided so as to be selectively connected to the antenna 50.

  In the above description, the antenna duplexer 17 is used to transmit and receive information with one device antenna 50. However, the present invention is not limited to this. That is, the device antenna 50 may be provided for each of the transmission circuit 15 and the reception circuit 16 without providing the antenna duplexer 17. In this case, the matching mechanism 26 may be installed between the transmission circuit 15 and the reception circuit 16 and each device antenna 50.

  On the other hand, the PDA 30 includes a control unit 35 that controls the entire PDA 30. An operation unit 34, a notification unit 36, a storage unit 37, and an external communication unit 38 are connected to the control unit 35 via the bus 32.

  The operation unit 34 includes, for example, numeric keys and operation buttons, and various operation inputs are performed by the operator.

  The notification unit 36 includes, for example, a speaker or a liquid crystal display, and performs various notifications including a warning notification described later.

  The storage unit 37 stores various information, various programs, and the like.

  The external communication unit 38 controls information communication performed with the reader body 10 via the cable 20.

  A control procedure executed by the control circuit 12 of the reader 1 during wireless communication will be described with reference to the flowchart of FIG. In FIG. 4, this flow is shown in FIG. 4, for example, when the PDA 30 is mounted on the mounting unit 4 of the reader main body 10 and the PDA 30 is connected to the reader main body 10 via the cable 20. To begin.

  First, in step S5, the control circuit 12 initializes a first flag for warning, which will be described later, and sets F = 0.

  Thereafter, in step S <b> 10, the control circuit 12 determines whether or not the device antenna 50 is bent based on the detection signal of the bending sensor 23. If the operator folds the device antenna 50 and switches to the second position in order to perform wireless communication with the plurality of wireless tags T separated from the reader 1, the determination is satisfied, and the routine goes to Step S15.

  In step S15, the control circuit 12 outputs a control signal to the matching mechanism 26, and switches the circuit selector switch 28 to the impedance matching circuit 27b side for long-distance communication. Thereby, the apparatus antenna 50, the transmission circuit 15, and the reception circuit 16 are connected via the antenna duplexer 17 and the impedance matching circuit 27b. Thereby, the impedance of the device antenna 50 is changed to an impedance for long-distance communication suitable for the folded device antenna 50 to communicate with a plurality of wireless tags T separated from the reader 1. Thereafter, the process proceeds to step S40.

  On the other hand, if the apparatus antenna 50 is not bent in step S10, the determination is not satisfied, and the apparatus antenna 50 is regarded as being in the first position upright with respect to the main body housing 2 of the reader 1, and the process proceeds to step S20. In step S <b> 20, the control circuit 12 determines whether or not the device antenna 50 is inserted into the storage container 40 based on the detection result of the proximity sensor 22. If the device antenna 50 is inserted into the storage container 40, the determination at Step S20 is satisfied, and the routine goes to Step S25.

  In step S25, the control circuit 12 sets the first flag to F = 0, and then proceeds to step S30. In step S30, the control circuit 12 outputs a control signal to the matching mechanism 26, and switches the circuit selector switch 28 to the impedance matching circuit 27a side for near field communication. As a result, the device antenna 50 is connected to the transmission circuit 15 and the reception circuit 16 via the antenna duplexer 17 and the impedance matching circuit 27a for near field communication. Thereby, the impedance of the device antenna 50 is suitable for short-range communication suitable for the device antenna 50 inserted into the storage container 40 to communicate with the plurality of wireless tags T around the device antenna 50 in the storage container 40. The impedance is changed. Thereafter, the process proceeds to step S40.

  On the other hand, if the device antenna 50 is not inserted into the storage container 40 in step S20, the determination is not satisfied, and the control circuit 12 sets the first flag to F = 1, and then proceeds to step S40.

  In step S40, the control circuit 12 determines whether or not the trigger switch 6 is turned on. When the operator holds the handle 3 of the reader 1 and presses the trigger switch 6, the detection signal is input to the control circuit 12, the determination in step S40 is satisfied, and the process proceeds to step S45. If the trigger switch 6 has not been pressed, the determination is not satisfied and the routine returns to step S5, and the same procedure from step S5 is repeated.

  In step S45, the control circuit 12 determines whether or not the first flag is F = 1. As described above, when the device antenna 50 is not bent and is not inserted, F = 1, so the determination is satisfied. This determination has the following significance. That is, when the device antenna 50 is not bent, the device antenna 50 is inserted into the storage container 40 and short-range communication with the plurality of wireless tags T in the storage container 40 is scheduled. Nevertheless, when the determination is satisfied, that is, when the device antenna 50 is bent but not inserted into the storage container 40, the device antenna 50 is in a use state incompatible with the above. In such a case, the determination at step S45 is not satisfied, and the routine goes to step S50.

  In step S50, the control circuit 12 outputs a control signal to the notification unit 36 of the PDA 30 via the communication control unit 11 of the reader body 20, the cable 20, the external communication unit of the PDA 30, and the control unit 35. In response to this, the notification unit 36 notifies a non-compliance warning that the use state of the device antenna 50 is non-conforming by voice, flashing light, a text message, etc., and alerts the operator. Thereafter, this flow is terminated.

  On the other hand, when the device antenna 50 is bent and when the device antenna 50 is not bent and inserted, F = 0 as described above, and thus the determination in step S45 is not satisfied. In this case, unlike the above, since the device antenna 50 is in a usage state that matches the above, and there is no need for a warning, the process proceeds to the communication processing in step S100.

  In step S100, a communication process (see FIG. 5 described later) with the wireless tag T via the device antenna 50 is performed, and then this flow ends.

  In the flowchart of FIG. 4 described above, the procedure of step S10 constitutes the switching determination unit described in each claim. Further, the procedure of step S20 constitutes an insertion determination means, the procedure of step S45 constitutes an instruction determination means, and the procedure of step S50 constitutes a notification means.

  The communication process in step S100 will be described with reference to the flowchart in FIG.

  First, in step S110, the control circuit 12 starts reading information by wireless communication from the wireless tag T within the communication range S. Specifically, the control circuit 12 of the reader 1 transmits a tag reading signal for reading information stored in the RFID tag circuit section To of the RFID tag T within the communication range S via the transmission circuit 15 and the reader antenna 10. It transmits to the RFID circuit part To and prompts a reply. The communication range S is a short-range range around the device antenna 50 inserted into the storage container 40 in which the wireless tag T is stored when the device antenna 50 is not bent (see FIG. 2A). When the device antenna 50 is bent, it is a long distance range away from the reader 1 (see FIG. 2B).

  Then, the process proceeds to step S120, and the control circuit 12 determines whether information has been acquired from the wireless tag T within the communication range S by wireless communication. Specifically, the control circuit 12 determines whether or not the response signal returned from the RFID tag circuit section To within the communication range S corresponding to the tag reading signal has been received via the device antenna 50 and the receiving circuit 16. To do. Until the response signal is received, the determination in step S120 is not satisfied and the process stands by in a loop. When the response signal is received, the determination in step S120 is satisfied, and the control circuit 12 acquires information stored in the RFID circuit section To based on the received response signal, and the process proceeds to step S125.

  In step S125, the control circuit 12 outputs the information acquired from the RFID tag circuit unit To of the RFID tag T to the PDA 30 via the communication control unit 11 and the cable 20. Thereby, the control unit 35 of the PDA 30 receives the information acquired from the RFID tag circuit unit To of the RFID tag T via the cable 20 and the external communication unit 38. Then, the control unit 35 performs predetermined processing such as displaying the information acquired from the RFID tag circuit unit To of the RFID tag T on the notification unit 36 and storing the information in the storage unit 37.

  Thereafter, the process proceeds to step S130, and the control circuit 12 determines whether or not the trigger switch 6 is turned off. Until the trigger switch 6 is turned off, the determination is not satisfied and the process returns to step S115, and reading of information from the wireless tag T is repeated. When the trigger switch 6 is turned off, the determination at step S130 is satisfied, and the routine goes to step S135.

  In step S135, the control circuit 12 stops reading information by wireless communication from the wireless tag T in the communication range S.

  Then, the process proceeds to step S140, and the control circuit 12 determines whether or not a predetermined end operation, for example, the reader 1 is turned off. If the ending operation has not been performed, the determination is not satisfied and the routine returns to step S10 and the same procedure is repeated. If an end operation has been performed, the determination is satisfied and this flow ends.

  As described above, in the reader 1 of the present embodiment, in a state where the device antenna 50 is switched to the first position, the reader antenna 1 is used by being inserted into the predetermined storage container 40 in which the plurality of wireless tags T are arranged. An electromagnetic wave is radiated toward the periphery of the device antenna 50. Thereby, the reader 1 can perform wireless communication with the plurality of wireless tags T existing around the device antenna 50 in the storage container 40.

  At this time, when the device antenna 50 performs wireless communication with respect to the plurality of wireless tags T in the storage container 40 as described above, the plurality of wireless tags T, the storage container 40, and the like exist in the immediate vicinity of the device antenna 50. Therefore, the deviation of the impedance of the device antenna 50 cannot be ignored. In the present embodiment, a proximity sensor 22 that detects the insertion state of the device antenna 50 is provided, and it is determined whether or not the insertion state is detected by the proximity sensor 22. When the device antenna 50 is inserted, the circuit selector switch 28 is switched so that the impedance matching circuit 27a for near field communication is connected to the antenna duplexer 17 and the device antenna 50. As a result, when the device antenna 50 is inserted into the storage container 40 and performs wireless communication with respect to the plurality of wireless tags T, the impedance of the device antenna 50 may be set to a value suitable for the communication state in the short distance. it can.

  On the other hand, in a state where the device antenna 50 is switched to the second position, the device antenna 50 can radiate electromagnetic waves in a direction linearly away from the main body housing 2. As a result, the reader 1 can perform wireless communication with the wireless tag T remote from the reader 1.

  As described above, according to the present embodiment, the operator can insert the device antenna 50 into the storage container 40, and the impedance of the device antenna 50 is adjusted to a suitable value by the insertion. Therefore, wireless communication can be smoothly performed with respect to the plurality of wireless tags T in the storage container 40, and information reading performance can be improved. The operator can also perform wireless communication with the wireless tag T away from the reader 1 by switching the device antenna 50 from the first position to the second position.

  In the present embodiment, in particular, a bending sensor 23 is provided for detecting that the device antenna 50 has been switched to the second position for performing wireless communication with the plurality of wireless tags T in the storage container 40. . As described above, when wireless communication is performed with respect to the wireless tag T that is away from the reader 1, the deviation of the impedance of the device antenna 50 is not a problem. On the other hand, when the device antenna 50 performs wireless communication with respect to the plurality of wireless tags T in the storage container 40, a deviation in impedance of the device antenna 50 cannot be ignored. Therefore, the matching mechanism 26 performs impedance matching control, specifically, increase / decrease control of the device antenna 50 according to whether the bending sensor 23 detects that the device antenna 50 has been switched to the second position. . Thereby, when the device antenna 50 is not switched to the second position and remains in the first position, the impedance of the device antenna 50 can be set to a value for short-range communication (see step S30 in FIG. 4). ). As a result, when the operator inserts the device antenna 50 into the storage container 40 as the first position, the impedance of the device antenna 50 is reliably adjusted to a value suitable for short-range communication. Thus, smooth wireless communication can be reliably performed with respect to the wireless tag T.

  Further, as described above, at the first position, the device antenna 50 is in a state suitable for short-range communication with the wireless tag T in the storage container 40. Therefore, it is not preferable that wireless communication is performed without being inserted into the storage container 24 even though the device antenna 50 is in the first position because the communication characteristics of the device antenna 24 are not met. Therefore, in the present embodiment, in particular, in step S45 of FIG. 4, it is determined whether the operator has erroneously instructed to start wireless communication in the non-conforming state as described above, and if the determination is satisfied, A predetermined warning notification is performed in S50. Thereby, it can be made to recognize reliably that it is said non-conformity state to an operator.

  Further, particularly in the present embodiment, the device antenna 50 is configured such that the width-direction dimension or the thickness-direction dimension of the distal end portion is smaller than the width-direction dimension or the thickness direction dimension other than the distal end portion. Thereby, even when many articles provided with the wireless tag T are packed in the storage container 40, the operator can easily and smoothly insert the device antenna 50 into the storage container 40.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit and technical idea of the present invention. Hereinafter, such modifications will be described in order. In each figure, the same reference numerals are given to the same parts as those in the above embodiment, and the description will be omitted or simplified as appropriate.

(1) When communication is started without a trigger when insertion of a device antenna is detected In this modification, when it is determined that the proximity sensor 22 has detected the insertion state of the device antenna 50, the operator The wireless communication by the apparatus antenna 50 is automatically started without turning on the trigger switch 6 according to.

  Control during wireless communication in this modification will be described with reference to FIG. 6, steps S7, S27, and S42 related to the second flag F1 for starting communication are added to the flowchart of FIG. 4 of the above embodiment. That is, step S7 is provided between step S5 and step S10, step S27 is provided between step S25 and step S30, and step S42 is provided between step S40 and step S5 and step S45. Yes.

  Similar to the above embodiment, first, in step S5, the control circuit 12 initializes the first flag to F = 0, and then proceeds to newly provided step S7. In step S7, the control circuit 12 initializes the second flag F1 and sets F1 = 0.

  Subsequent steps S10, S20, and S25 are the same as in the above embodiment, and the control circuit 12 determines whether or not the device antenna 50 is bent to the second position, and if this determination is not satisfied. It is determined whether or not the device antenna 50 is inserted into the storage container 40. If this determination is satisfied, the first flag is set to F = 0. When step S25 ends, the process proceeds to newly provided step S27.

  In step S27, the second flag F1 is set to F1 = 1. Thereafter, Step S30 and Step S40 are the same as in the above embodiment.

  In step S40, the control circuit 12 determines whether or not the trigger switch 6 is turned on, as in the above embodiment. When the trigger switch 6 is turned on and the determination is satisfied, the control circuit 12 executes Step S45 and Step S50 or Step S100 as in the above embodiment. That is, when the first flag F is 0 and the determination of step S45 is not satisfied, the control circuit 12 performs the communication process of step S100, and when the first flag F is 1 and the determination of step S45 is satisfied, the control circuit 12 is step S50. Warning notification. Thereafter, this flow is terminated.

  On the other hand, when the trigger switch 6 is not turned on and the determination is not satisfied in step S40, the process proceeds to newly provided step S42.

  In step S42, the control circuit 12 determines whether or not the second flag F1 is F1 = 1. If the device antenna 50 is bent to the second position, and if the device antenna 50 is not bent to the second position but not inserted into the storage container 40, the determination is satisfied because F1 = 0. Instead, the process returns to step S5, and the procedure after step S5 is repeated.

  On the other hand, when the device antenna 50 is inserted into the storage container 40 without being bent to the second position, since F1 = 1 in step S27, the determination in step S42 is satisfied, and the above-described case is satisfied. Control goes to step S45. In this case, since F = 0 in step S25 before step S27, the determination in step S45 is not satisfied, and the communication process in step S100 is executed. Thereby, the wireless communication by the apparatus antenna 50 is automatically started without the operator turning on the trigger switch 6.

  In addition, in the above, the procedure of step S42 comprises the communication control means as described in each claim.

  According to this modification, when the operator inserts the device antenna 50 into the storage container 40, no separate operation is required and wireless communication by the device antenna 50 is started. As a result, the operation burden on the operator can be reduced and the convenience can be improved.

(2) When the axial length of the device antenna is variably configured In the above embodiment, the device antenna 50 is formed in a tapered rectangular tube shape, and the axial length is fixed. The thickness may be variable.

  That is, as shown in FIG. 7A, the device antenna 52 of this modification is configured by fitting antenna rods 52a to 52d made of a plurality of cylindrical conductors having different cross-sectional dimensions so as to be extendable. The device antenna 52 is attached to the antenna support portion 51 at the position of the antenna rod 52a having the maximum cross section. As shown in FIG. 7A, the device antenna 52 has the shortest length in which the antenna rods 52a to 52d are expanded and contracted from each other as shown in FIG. Up to the length, the axial length can be changed in a plurality of stages, for example, three stages. In addition, in response to the fact that the axial length of the device antenna 52 can be changed in three stages as described above, a length sensor 24 for detecting the axial length of the device antenna 52 is provided (described later). 8).

  As shown in FIG. 8, the reader main body 10 of the reader 1 according to the present modification includes a matching mechanism 26 that includes three impedance matching circuits 27 a 1 for short-range communication corresponding to three-stage length changes of the device antenna 52. 27a2 and 27a3, and an impedance matching circuit 27b for long-distance communication are provided. Then, the control circuit 12 outputs a switching control signal to the circuit selector switch 28 according to the detection result of the axial length of the device antenna 52 by the length sensor 24. The circuit changeover switch 28 selects one of the impedance dance matching circuits 27a1, 27a2, and 27a3 for short-range communication and the impedance dance matching circuit 27b for long-range communication as the antenna duplexer 17 and the device antenna 52. Switching connection is unified. Thereby, the impedance of the device antenna 52 is matched and controlled to an appropriate value according to the axial length of the device antenna 52 detected by the length sensor 24.

  In the above description, it is assumed that when the operator inserts the device antenna 52 into the storage container 40 without bending it, the length is changed in a plurality of stages, and a plurality of impedance dance matching circuits 27a1 for short-range communication are used. 27a2 and 27a3 are provided, but the present invention is not limited to this. On the contrary, assuming that the operator changes the length in a plurality of stages when the apparatus antenna 52 is bent and used, a plurality of impedance dance matching circuits for long-distance communication may be provided and switched. . It is not limited to this. Further, a large number of impedance dance matching circuits may be provided in multiple stages from a short distance to a middle distance and then used as appropriate.

  As described above, in the present modification, the axial length of the device antenna 52 is made variable, so that even when electromagnetic waves of a plurality of types of frequencies are used, the antenna length suitable for the wavelength corresponding to each frequency can be easily obtained. Can be realized. At this time, although the electrical length of the antenna changes as the axial length of the device antenna 52 changes, the matching mechanism 26 tracks the change in the electrical length by matching the impedance according to the axial length. Thus, the impedance value can be surely adapted.

(3) When the device antenna is a dipole antenna In the above embodiment, the device antenna 50 is a λ / 4 monopole antenna that is used with one end grounded, but is a non-grounded λ / 2 dipole antenna. Also good. FIG. 9 shows an operation mode of the device antenna of this modification.

  As shown in FIG. 9, in the device antenna 54 of this modification, an antenna piece 54 a made of a conductor having a length corresponding to a quarter of the frequency λ is attached to the antenna support 51 so as to be symmetrical. Yes. The antenna support portion 51 has substantially the same length as the antenna piece 54 a and is provided upright with respect to the main body housing 2 at the front end portion of the main body housing 2 of the reader main body 10. The antenna piece 54a is formed in a tapered shape so as to be easily inserted when the device antenna 54 is inserted into the storage container 40.

  When the operator rotates the device antenna 54 by hand, the device antenna 54 is in the first position in FIG. 9A standing upright with respect to the main body housing 2 and in the lateral direction with respect to the main body housing 2. And can be switched to the second position in FIG. 9B which is substantially orthogonal to the first position.

  According to this modification, even when a dipole antenna is used, the same effect as in the above embodiment can be obtained.

(4) When the reader is a stationary type In the above-described embodiment, the portable reader 1 having the gun-type reader body 10 is shown as the wireless tag communication device, but a stationary reader may be used. A reader of this modification is shown in FIG.

  As shown in FIG. 10, the reader 1 </ b> A of this modification includes a table-shaped main body housing 2 </ b> A and a device antenna 56. A communication circuit (not shown) that is connected to the device antenna 56 and performs predetermined processing related to wireless communication is provided in the main body housing 2A. The device antenna 56 is rotatably attached to the upper surface of the main housing 2A by the antenna support portion 51. When the operator rotates the device antenna 56 by hand, the device antenna 56 is bent in the lateral direction with respect to the main body housing 2A and the first position where the device antenna 56 stands upright upward. The position can be switched to a second position substantially orthogonal to the position.

  In the first position where the device antenna 56 stands upright, the reader 1 </ b> A of the present modified example presses the storage container 40 from above on the device antenna 56, and stabs the device antenna 56 from the bottom of the storage container 40 into the storage container 40. Insert (see arrow). Thereby, similarly to the said embodiment, the apparatus antenna 56 can perform radio | wireless communication with the some radio | wireless tag T arrange | positioned in the storage container 40. FIG.

  In the present modification, even when a stationary reader is used, the same effect as in the above embodiment can be obtained.

(5) Others In the above description, the case where the device antennas 50, 52, 54, and 56 are inserted into the storage container 40 mainly from the holes provided in the storage container 40 has been described as an example. The lid of 40 may be opened slightly to create a gap, and the device antenna may be inserted into the storage container through the gap.

  In the above description, the device antennas 50, 52, 54, and 56 are rotatably supported at the first position and the second position. However, the present invention is not limited to this. That is, the device antennas 50, 52, 54, and 56 may be provided so as to be attachable / detachable with respect to the main body housings 2 and 2A so as to be in the first position and the second position, respectively. In these cases, the same effect as described above is obtained.

  The embodiment and the modification of the present invention have been described above. However, the present invention is not limited to this, and the methods according to the above-described embodiment and each modification may be used in appropriate combination other than those described above.

  In addition, although not illustrated one by one, the present invention is implemented with various modifications within a range not departing from the gist thereof.

1,1A reader (wireless tag communication device)
2,2A Main unit housing 6 Trigger switch (communication instruction means)
10 Reader body 22 Proximity sensor (insertion detection means)
23 Bending sensor (switching detection means)
24 Length sensor (length detection means)
26 Matching means 40 Storage container 50, 52 Device antenna 54, 56 Device antenna 51 Switching support means T Wireless tag

Claims (7)

A device antenna configured to be inserted into a predetermined storage container in a substantially linear shape, and for wireless communication with a wireless tag;
A main body housing provided with a communication circuit connected to the device antenna for performing predetermined processing relating to wireless communication;
A switch provided at an end of the main body casing and supporting the device antenna so as to be switchable between a first position standing upright with respect to the main body casing and a second position substantially orthogonal to the upright position. Support means;
Insertion detecting means for detecting a state in which the device antenna is inserted into the predetermined storage container;
Insertion determination means for determining whether or not the apparatus antenna is inserted into the predetermined storage container by the insertion detection means;
In accordance with the determination result of the insertion determination means, matching means for matching and controlling the impedance of the device antenna;
A wireless tag communication device comprising: The device antenna is configured to have a variable axial length,
A length detecting means for detecting the axial length of the device antenna;
The matching means includes
2. The RFID tag communication apparatus according to claim 1, wherein the impedance of the apparatus antenna is matched and controlled according to the axial length of the apparatus antenna detected by the length detection means. Switching detection means for detecting a state in which the device antenna is switched to the second position;
Switching determination means for determining whether or not the state where the device antenna is switched to the second position is detected by the switching detection means;
Have
The matching means includes
The wireless tag communication device according to claim 1 or 2, wherein matching control is performed on the impedance of the device antenna in accordance with a determination result of the switching determination unit. A communication instruction means by which an operator can instruct start of wireless communication;
The switching determination unit determines that the switching detection unit has not detected the switching state of the device antenna to the second position, and the insertion determination unit causes the insertion detection unit to detect the predetermined state of the device antenna. Instruction determining means for determining whether the communication instruction means has instructed to start the wireless communication when it is determined that the state inserted into the storage container has not been detected;
A notification means for performing a predetermined warning notification when it is determined by the instruction determination means that there is an instruction to start the wireless communication;
The wireless tag communication apparatus according to claim 3, further comprising: The device antenna is
The width direction dimension or thickness direction dimension of a front-end | tip part is comprised so that it may become smaller than the width direction dimension or thickness direction dimension other than the said front-end | tip part, The structure of Claim 1 thru | or 4 characterized by the above-mentioned. The wireless tag communication device according to any one of claims. Communication control for controlling to start wireless communication by the device antenna when the insertion determination unit determines that the insertion detection unit has detected the insertion state of the device antenna in the predetermined storage container. The wireless tag communication apparatus according to claim 1, further comprising: means. The wireless tag communication device according to claim 1, further comprising a grip portion that is positioned at a lower portion of the main body housing and can be gripped by an operator.

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