JP2019061305A - Crime prevention alarm device - Google Patents

Abstract

To provide a crime prevention alarm device that can automatically determine the opening/closing state of a fitting without a built-in battery of a slave unit mounted on the fitting.SOLUTION: A crime prevention alarm device 1 of this embodiment comprises: an RF tag 10 mounted on the open/close section of a window 2; and an alarm device 11 for a radio communication with the RF tag 10. The alarm device 11 includes: a reader-writer antenna 112 to be used for the radio communication with the RF tag 10; a reader-writer unit 111 for sending a carrier wave to supply an electric power to the RF tag 10, and for performing processing to obtain the reception state of the radio wave sent by the RF tag 10; and an alarm control unit 110 for performing processing to determine the opening/closing state of the window 2 on which the RF tag 10 sending the radio wave is mounted by obtaining the reception state of the radio wave sent by the RF tag 10 from the reader-writer unit 111.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a security alarm device that automatically detects opening and closing of a fixture such as a window or a door provided in a building such as a residence and notifies an alarm sound.

  Conventional security alarm devices that automatically detect the opening and closing of fixtures such as windows and doors provided in buildings such as residences and report an alarm sound are a child machine that incorporates a sensor used for detecting the opening and closing of a fixture, and a child machine And at least a base unit for wireless communication.

  It is common to use a magnetic sensor as a sensor for detecting the opening and closing of the fixture, and the child device of the security alarm device disclosed in Patent Document 1 is taken to the fixture as a sensor for automatically detecting the opening and closing of the fixture. It incorporates a magnetic sensor that measures the magnetic force generated by the magnet. The child device of the security alarm device disclosed in Patent Document 1 transmits the measurement result of the magnetic force to the parent device of the security alarm device by wireless communication, and the parent device of the security alarm device changes the magnetic force caused by the opening of the fixture. Automatically detect that the fixture has opened.

  In the conventional security alarm device described above, in addition to the parent device for notifying an alarm sound, a power supply is also required for a child device incorporating a sensor such as a magnetic sensor. The parent machine of the crime prevention alarm device can supply power from the electricity distribution panel of the building because the installation place of the parent machine can be decided arbitrarily, but the child machine of the crime prevention alarm device installed in the window or door opens and closes the fixtures In order to install in a part, as described in Patent Document 2, it is common for a child device to incorporate a battery.

JP, 2011-3168, A JP, 2011-3167, A

  However, there is a problem in the security alarm device in which the battery supplying power is built in the slave unit, the security alarm device does not operate normally when the power of the battery built in the slave unit is exhausted.

  Therefore, an object of the present invention is to provide a security alarm device capable of automatically judging the open / close state of a fixture such as a window or a door without incorporating a battery in a child machine installed in the fixture such as a window or a door. .

  The present invention for solving the above-mentioned problems is a security alarm device provided with an RF tag attached to an opening and closing part of a fixture and an alarm device wirelessly communicating with the RF tag. In order to solve the problems described above, the alarm device according to the present invention has an antenna used for wireless communication with the RF tag, transmits a carrier wave that supplies power to the RF tag, and transmits the RF tag. The reader / writer unit performs processing to acquire the reception status of the radio wave, and the reception status of the radio wave transmitted by the RF tag is acquired from the reader / writer unit, and the opening / closing state of the fixture attached with the RF tag transmitting the radio wave It is a burglar alarm system characterized by having an alarm control part which performs processing to judge.

  As the reception status of the radio wave transmitted by the RF tag, the received radio wave intensity when the radio wave transmitted by the RF tag is received can be used. When using the received radio wave intensity when the radio wave transmitted by the RF tag is used, the reader / writer unit of the alarm device according to the present invention receives the received radio wave intensity when the radio wave transmitted by the RF tag is received The alarm control unit of the alarm device according to the present invention acquires the situation and determines the open / close state of the fixture, the received radio wave intensity when the fixture is closed and the received radio wave intensity acquired by the reader / writer unit When the difference is greater than or equal to the threshold value, processing is performed to determine that the fixture attached with the RF tag has become open.

  As the reception status of the radio wave transmitted by the RF tag, the reception status of the tag identifier placed on the radio wave can be used. When the reception status of the tag identifier placed on the radio wave transmitted by the RF tag is used, the security alarm device according to the present invention is configured to receive the carrier wave that reaches the RF tag in any one of the open state and the closed state. A radio wave blocking member arranged to block is provided. In addition, when the RF tag according to the present invention receives a command for reading the tag identifier, it transmits a radio wave carrying the tag identifier stored in the RF tag, and the reader / writer unit of the alarm device according to the present invention After transmitting the carrier wave carrying the command, the tag control unit acquires the tag identifier carried on the radio wave as the reception status of the radio wave sent out by the RF tag, and the alarm control unit of the alarm device according to the present invention A process of determining the open / close state of the fixture is performed based on whether or not the tag identifier registered in the alarm control unit has been acquired.

  When the radio wave blocking member is arranged to block the carrier wave reaching the RF tag when the fixture attached with the RF tag is closed, the reader / writer unit of the alarm device according to the present invention is the RF tag The tag control unit acquires the tag identifier on the radio wave sent out as the reception status, and the alarm control unit determines the tag identifier registered in the alarm control unit as the processing for determining the open / close state of the fixture. When it is acquired, processing is performed to determine that the fixture attached with the RF tag has become open. Further, when the radio wave blocking member is disposed to block the carrier wave reaching the RF tag when the fixture attached with the RF tag is open, the reader / writer unit of the alarm device according to the present invention The tag control unit acquires the tag identifier on the radio wave transmitted by the RF tag as the reception status, and the alarm control unit determines the open / close state of the fixture by processing the tag identifier registered in the alarm control unit. If the writer unit does not acquire the information, it is determined that the fixture on which the RF tag is attached is in the open state.

  The above-described security alarm device according to the present invention uses a carrier wave so that the open / close state of the fixture can be automatically determined and the alarm sound can be notified even if the child machine installed in the fixture such as a window or door does not incorporate a battery. It has a function to automatically determine the open / close state of the fixture based on the reception status of radio waves sent from the RF tag by attaching an RF tag supplied with power to the opening / closing part of the fixture.

A figure explaining composition of a crime prevention alarm device concerning this embodiment. The block diagram of the crime prevention alarm device concerning this embodiment. A figure explaining basic operation of an alarm control part with which a crime prevention alarm device is provided. The figure explaining the relationship between the opening / closing state of a window, and received electromagnetic wave intensity. FIG. 7 is a diagram for explaining processing of determining an open / close state of a window in the first embodiment. FIG. 7 is a view for explaining the arrangement of the radio wave blocking member in the second embodiment. FIG. 8 is a diagram for explaining processing of determining the open / close state of the window in the second embodiment. FIG. 14 is a view for explaining the arrangement of the radio wave blocking member in the third embodiment. FIG. 14 is a diagram for explaining processing of determining the open / close state of the window in the third embodiment.

  We will now describe preferred embodiments of the present invention. The following description does not limit the technical scope of the present invention, and is described to aid understanding.

  FIG. 1 is a diagram for explaining the configuration of the security alarm device 1 according to the present embodiment. The crime prevention alarm device 1 according to the present embodiment uses the RF tag 10 used for individual identification by wireless to automatically determine the open / close state of a member such as a door provided in a building such as a residence and to generate an alarm sound. It is an apparatus configured to notify.

  In FIG. 1, the fixture is illustrated as a window 2, and the security alarm device 1 according to the present embodiment uses the RF tag 10 attached to the opening / closing portion of the window 2 and the window 2 using the communication status with the RF tag 10. The alarm device 11 is provided to notify an alarm when the open / close state is determined and the open state is determined.

  In the security alarm device 1 according to the present embodiment, the RF tag 10 is a device attached to the opening / closing portion of the window 2, and the alarm device 11 is an device attached in a state of being fixed at a location away from the window 2. In FIG. 1, the window 2 provided in the room of the building has two interior windows 20 as the inside and the outside window 21 as the outside, and the inside window 20 and the outside window 21 are crescent lock 22 A lockable sliding window is used, and an RF tag 10 is attached to each of an inner window 20 and an outer window 21 serving as an opening and closing part of the window 2 which is a sliding window.

  The position to attach the RF tag 10 may be arbitrary as long as it is the opening and closing part of the window 2, but in this embodiment, the RF tag 10 is attached to a position close to the ceiling of the pull side 23 in each of the inner window 20 and the outer window 21. There is. The reason why the RF tag 10 is attached near the ceiling is because it is difficult for a human hand to reach the RF tag 10. The alarm device 11 is attached at a position capable of wirelessly communicating with the RF tag 10 attached to the opening and closing portion of the window 2. In FIG. 1, the alarm device 11 is fixedly attached to a wall where the window 2 is not provided as a position where wireless communication can be performed with the RF tag 10 attached to each of the inner window 20 and the outer window 21.

  Details of the security alarm device 1 according to the present embodiment will be described. FIG. 2 is a block diagram of the security alarm device 1 according to the present embodiment.

  A commercially available product (general-purpose product) can be used as the RF tag 10 of the security alarm device 1 according to the present embodiment. The type of the RF tag 10 may be an active type that operates with power supplied from a built-in battery, but in the present embodiment, it is a passive type that operates with a carrier wave from a reader / writer. The communication method according to the passive type RF tag 10 includes an electromagnetic induction method of supplying power and transferring data using a magnetic field, but in the present embodiment, a carrier wave of UHF band (952.2 to 953.8 MHz band) is used The radio wave system is used to supply power and transfer data.

  The RF tag 10 of the security alarm device 1 according to the present embodiment has two radiation elements and a feeding circuit so that power supply and data transfer can be performed using radio waves in the UHF band (952.2 to 953.8 MHz band). An IC chip 100 connected to the antenna 101 and a feeding circuit of the tag antenna 101 is incorporated. The IC chip 100 built in the RF tag 10 stores a tag identifier used to identify the RF tag 10, and when it receives a carrier wave on which a command (for example, a read command) for reading the tag identifier is modulated and received, the tag antenna 101 And transmit the radio wave on which the tag identifier stored in the IC chip 100 is modulated.

  In the case of a window having a configuration in which a glass is inserted into an aluminum window sash, when the RF tag 10 is attached to the aluminum sash, the communication characteristics of the RF tag 10 are significantly impaired due to the effect of the aluminum window sash, When the RF tag 10 is attached to the aluminum window sash, a device such as providing a magnetic material such as ferrite between the aluminum window sash and the RF tag 10 is required.

  The alarm device 11 of the crime prevention alarm device 1 according to the present embodiment transmits a carrier wave for supplying power to the RF tag 10 or receives a reader / writer antenna 112 used for receiving a radio wave transmitted by the RF tag 10 A reader / writer unit 111 that executes processing related to communication, an alarm control unit 110 configured with a processor, a memory, and the like, and an alarm unit 113 that notifies an alarm.

  When the radio communication frequency with the RF tag 10 is in the UHF band, a dipole antenna or a planar antenna is used for the reader / writer antenna 112 of the reader / writer unit 111. After transmitting the carrier wave for supplying power to the RF tag 10, the reader / writer unit 111 of the security alarm device 1 modulates a command for reading the tag identifier from the RF tag 10 and transmits the carrier wave loaded thereon. Further, when the reader / writer unit 111 of the security alarm device 1 receives the radio wave sent by the RF tag 10, it performs processing to acquire the reception status of the radio wave sent by the RF tag 10, and receives the radio wave sent by the RF tag 10. The situation is handed over to the alarm control unit 110.

  The alarm unit 113 included in the alarm device 11 of the security alarm device 1 is a device for notifying an alarm notifying that the window 2 has been opened from the closed state, and the alarm unit 113 according to the present embodiment has the window 2 closed. A siren sounds to indicate that the state has been opened.

  From here, the operation of the alarm control unit 110 provided in the alarm device 11 of the security alarm device 1 will be described. FIG. 3 is a diagram for explaining the basic operation of the alarm control unit 110 provided in the security alarm device 1.

  When the alarm control unit 110 included in the alarm device 11 of the security alarm device 1 determines the open / close state of the window 2 using the communication status with the RF tag 10 and executes the process of notifying an alarm when it is determined to be the open state After the reader / writer unit 111 is operated to transmit the carrier wave for supplying power to the RF tag 10, the procedure illustrated in FIG. 3 is repeatedly executed until it is determined that the window 2 is opened.

  In the procedure illustrated in FIG. 3, the alarm control unit 110 of the alarm device 11 first modulates a command for reading the tag identifier stored in the RF tag 10 using the reader / writer unit 111, Processing to determine the open / close state of the window 2 to which the RF tag 10 that has sent the radio wave is attached using the reception status of the radio wave that the RF tag 10 that received the command has sent after performing the sending process (S1) (S2), and the process branches according to the determination result of the open / close state of the window 2 (S3). The alarm control unit 110 of the alarm device 11 ends the procedure illustrated in FIG. 3 without notifying the alarm when the determination result of the open / close state of the window 2 is the closed state, and the alarm control unit 110 of the alarm device 11 When the determination result of the open / close state of the window 2 is the open state, the alarm unit 113 is operated to perform a process of notifying an alarm (S4), and the procedure illustrated in FIG. 3 ends.

  In step S1 of FIG. 3, when the alarm control unit 110 of the alarm device 11 transmits a command, the RF tag 10 stores the RF tag 10 which is activated by the power supplied by the carrier wave transmitted by the alarm device 11. Modulate the tag identifier and send out the radio wave. As data acquired by the reader / writer unit 111 of the alarm device 11 from the radio wave transmitted by the RF tag 10 in step S2 of FIG. 3, the tag identifier placed on the radio wave transmitted by the RF tag 10, the RF tag 10 The received radio wave intensity which is the radio wave intensity when the alarm device 11 receives the radio wave sent out by the user can be considered.

  When a plurality of RF tags 10 (two in the present embodiment) are used, the reader / writer unit 111 of the alarm device 11 executes a process related to anti-collision, and the alarm control unit 110 of the alarm device 11 performs a plurality of processes. For each of the RF tags 10, processing for determining the open / close state of the window 2 to which the RF tag 10 that has transmitted the radio waves is attached is executed using the reception condition of the radio waves transmitted by the RF tag 10.

  From here, several embodiments of the process of determining the open / close state of the window 2 will be described.

Example 1
A first embodiment of the process of determining the open / close state of the window 2 will be described. Example 1 of the process of determining the open / close state of the window 2 determines the open / close state of the window 2 using the received radio wave intensity which is the radio wave intensity when the alarm device 11 receives the radio wave transmitted by the RF tag 10 It is an example.

  FIG. 4 is a diagram for explaining the relationship between the open / close state of the window 2 and the received radio wave intensity. In the first embodiment, the configuration of the security alarm device 1 is the same as that shown in FIG. As shown in FIG. 1, by attaching the RF tag 10 and the alarm device 11, the position of the alarm device 11 does not change with the opening and closing of the window 2, but the position of the RF tag 10 changes with the opening and closing of the window 2. , The distance between the RF tag 10 and the alarm device 11 changes with the opening and closing of the window 2.

  FIG. 4A is a diagram for explaining the relationship between the open / close state of the outer window 21 and the received radio wave intensity. When the open / close state of the outer window 21 changes from the closed state to the open state, the distance between the RF tag 10 and the alarm device 11 Changes from Lo1 which is the distance in the closed state to Lc1 shorter than Lo1. Since the radio wave intensity of the radio wave transmitted by the RF tag 10 is constant, the longer the distance between the RF tag 10 and the alarm device 11, the received radio wave intensity when the alarm device 11 receives the radio wave transmitted by the RF tag 10 is It becomes smaller. Since the distance between the RF tag 10 and the alarm device 11 becomes short when the outer window 21 is opened from the closed state, the received radio wave intensity when the alarm device 11 receives the radio wave transmitted by the RF tag 10 is the outer window It becomes larger when the outer window 21 is opened than when 21 is closed.

  FIG. 4B is a diagram for explaining the relationship between the open / close state of the inner window 20 and the received radio wave intensity. When the open / close state of the inner window 20 changes from the closed state to the open window 21, the RF tag 10 and alarm The distance between the devices 11 changes from Lo2 which is the distance in the closed state to Lc2 which is longer than Lo2. Therefore, when the inner window 20 changes from the closed state to the open state, the distance between the RF tag 10 and the alarm device 11 becomes longer, so the received radio wave intensity when the alarm device 11 receives the radio wave transmitted by the RF tag 10 is When the inner window 20 is in the open state, it becomes smaller than when the inner window 20 is in the closed state.

  As described above, regardless of the inner window 20 and the outer window 21, when the window 2 is opened from the closed state, the received radio wave intensity when the alarm device 11 receives the radio wave transmitted by the RF tag 10 changes, The reader / writer unit 111 of the alarm device 11 according to the first embodiment adds the tag identifier on the radio wave transmitted by the RF tag 10 as the reception status of the radio wave transmitted by the RF tag 10 and the radio wave transmitted by the RF tag 10 Is received by the alarm device 11 and at least the open / closed state of the window 2 is determined using the tag identifier and the received radio wave intensity.

  The process of determining the open / close state of the window 2 in the first embodiment will be described. FIG. 5 is a diagram for explaining the process of determining the open / close state of the window 2 in the first embodiment.

  The alarm control unit 110 of the alarm device 11 first determines whether the tag identifier put on the radio wave transmitted by the RF tag 10 is the tag identifier stored in the RF tag 10 of the security alarm device 1 or not. Execute (S10). In the alarm control unit 110 of the alarm device 11 according to the first embodiment, the tag identifier stored in the RF tag 10 used in the security alarm device 1 is registered in advance so that the tag identifier can be determined. In this embodiment, since the RF tag 10 is attached to each of the inner window 20 and the outer window 21, the tag identifier stored in the RF tag 10 attached to the inner window 20 and the RF tag 10 attached to the outer window 21 The tag identifier stored in the unit is registered in the alarm control unit 110 of the alarm device 11.

  The alarm control unit 110 of the alarm device 11 branches the process according to the determination result of the tag identifier (S11). When it is determined that the tag identifier put on the radio wave transmitted by the RF tag 10 is not the tag identifier registered in advance in the alarm control unit 110, the alarm control unit 110 of the alarm device 11 does not relate to the security alarm device 1 The procedure of FIG. 3 ends without determining the tag identifier and determining the open / close state of the window 2, and the tag identifier on the radio wave transmitted by the RF tag 10 is registered in advance in the alarm control unit 110. If it is determined that the identifier is the identifier, the alarm control unit 110 of the alarm device 11 executes a process of determining whether the difference between the received radio wave intensities is equal to or greater than the threshold (S12).

  The alarm control unit 110 of the alarm device 11 according to the first embodiment stores the received radio wave intensity when the window 2 is in the closed state, and stores the threshold value used to determine the open / close state of the window 2. In FIG. 1, since the RF tag 10 is attached to each of the inner window 20 and the outer window 21, the alarm control means of the alarm device 11 according to the first embodiment stores the RF tag 10 attached to the inner window 20. The received radio wave intensity when the inner window 20 is closed is stored in association with the tag identifier, and the outer window is stored in association with the tag identifier stored in the RF tag 10 attached to the outer window 21. The received radio wave intensity when 21 is closed is stored. If the threshold used to determine the open / close state of the window 2 is a value that can determine the open state in each of the inner window 20 and the outer window 21, one threshold may be used to determine the open / close state of the window 2.

  The alarm control unit 110 of the alarm device 11 according to the first embodiment receives the received radio wave intensity in the closed state corresponding to the tag identifier placed on the radio wave transmitted by the RF tag 10 in step S12 of FIG. The difference of the received radio wave intensity when the alarm device 11 receives the radio wave sent out by 10 is calculated, and it is determined whether this difference is equal to or more than a threshold.

  The alarm control unit 110 of the alarm device 11 according to the first embodiment branches the process according to the determination result of the received radio wave intensity (S13). If the difference in received radio wave intensity is less than the threshold, the alarm control unit 110 of the alarm device 11 according to the first embodiment determines that the window 2 attached with the RF tag 10 transmitting the radio wave with the tag identifier is closed. (S14), the procedure of FIG. 5 ends, and when the difference in received radio wave intensity is greater than or equal to the threshold, the alarm control unit 110 of the alarm device 11 according to the first embodiment sends out the radio wave carrying the tag identifier. The window 2 to which the tag 10 is attached is determined to be open (S15), and the procedure of FIG. 5 ends.

  In the first embodiment described above, the open / close state of the window 2 to which the RF tag 10 is attached is determined using the tag identifier and the received radio wave intensity. However, in one of the open state and the closed state, the RF is It is possible to determine the open / close state of the window 2 by adding the radio wave blocking member arranged to block the carrier wave reaching the tag 10 to the configuration of the security alarm device 1 and using the presence or absence of the radio wave transmitted by the RF tag 10. An embodiment in which the open / close state of the window 2 is determined from the presence or absence of the radio wave transmitted from the RF tag 10 will be described.

Example 2
A second embodiment will be described in which the open / close state of the window 2 is determined based on the presence or absence of radio waves transmitted by the RF tag 10. In the second embodiment, when the alarm device 11 receives a radio wave transmitted by the RF tag 10 attached to the window 2, at least one of the windows 2 attached with the RF tag 10 transmitting the radio wave is opened. It is comprised so that it may determine.

  FIG. 6 is a view for explaining the arrangement of the radio wave blocking member 12 in the second embodiment, and FIG. 6 (a) is a view for explaining the situation when the window 2 is in the closed state; 6 is a view for explaining the situation when the window 2 is in the closed state.

  As illustrated in FIGS. 6A and 6B, in the second embodiment, when the window 2 to which the RF tag 10 is attached is in a closed state, the wireless communication between the RF tag 10 and the alarm device 11 is inhibited. The radio wave blocking member 12 is disposed. Thus, by arranging the radio wave blocking member 12, when the window 2 is opened, the RF tag 10 attached to the window 2 transmits radio waves. The radio wave blocking member 12 can be made of a material having a radio wave shielding function. It is preferable to use an aluminum plate having a relatively low specific gravity for the radio wave blocking member 12.

  By attaching the radio wave blocking member 12 as illustrated in FIG. 6, as illustrated in FIG. 6A, when the window 2 is in the closed state, the carrier wave transmitted by the alarm device 11 is blocked by the radio wave blocking member 12. And the RF tag 10 attached to the window 2 does not transmit the radio wave carrying the modulated tag identifier, and the reader / writer unit 111 of the alarm device 11 does not transmit the radio wave. Can not receive the radio wave transmitted by the RF tag 10. On the other hand, when the window 2 is open, the carrier wave transmitted by the alarm device 11 reaches the RF tag 10 attached to the window 2. Therefore, the RF tag 10 attached to the window 2 modulates the tag identifier. The reader / writer unit 111 of the alarm device 11 can receive the radio wave transmitted by the RF tag 10.

  Although only the case of the outer window 21 is described in FIG. 6, the inner window 20 can be configured in the same manner.

  A process of determining the open / close state of the window 2 in the second embodiment will be described. FIG. 7 is a diagram for explaining the process of determining the open / close state of the window 2 in the second embodiment.

  The reader / writer unit 111 of the alarm device 11 acquires, as the reception status of the radio wave transmitted by the RF tag 10 receiving the command, the tag identifier placed on the radio wave transmitted by the RF tag 10 receiving the command (S20).

  The alarm control unit 110 of the alarm device 11 executes a process of determining whether the reader / writer unit 111 has acquired the tag identifier (S21), and branches the process according to the determination result (S22). If the reader / writer unit 111 can not acquire any tag identifier, the carrier wave does not reach any of the RF tags 10 attached to the window 2. Therefore, all the windows 2 attached with the RF tags 10 are closed. It determines with (S26) and the procedure of FIG. 7 is complete | finished.

  When the reader / writer unit 111 can obtain at least one tag identifier, the alarm control unit 110 of the alarm device 11 registers the tag identifier acquired by the reader / writer unit 111 in the alarm control unit 110 of the alarm device 11. A process of determining whether or not there is present is executed (S23), and the process branches according to the determination result (S24). As in the first embodiment, the tag identifier stored in the RF tag 10 used in the security alarm device 1 is registered in advance in the alarm control unit 110 of the alarm device 11 according to the second embodiment.

  If none of the tag identifiers acquired by the reader / writer unit 111 is registered in the alarm control unit 110 of the alarm device 11, it means that a tag identifier unrelated to the determination of the open / close state of the window 2 has been received. The alarm control unit 110 of 11 determines that the open / close state of the window 2 is all close (S25), and the procedure of FIG. 7 ends. In addition, if at least one tag identifier registered in advance in the alarm control unit 110 of the alarm device 11 is among the tag identifiers acquired by the reader / writer unit 111, at least one of the RF tags 10 attached to the window 2 Since the carrier wave has arrived at the terminal, the alarm control unit 110 of the alarm device 11 determines that the window 2 to which the RF tag 10 is attached is in the open state (S26), and the procedure of FIG. finish.

[Example 3]
A third embodiment will be described in which the open / close state of the window 2 is determined based on the presence or absence of radio waves transmitted by the RF tag 10. In the third embodiment, when the alarm device 11 can not receive the radio wave transmitted by the RF tag 10 attached to the window 2, the alarm device 11 opens at least one of the windows 2 to which the RF tag 10 transmitting the radio wave is attached. Is configured to be determined.

  FIG. 8 is a view for explaining the arrangement of the radio wave blocking member 13 in the third embodiment. FIG. 8 (a) is a view for explaining the situation when the window 2 is in the closed state. 6 is a view for explaining the situation when the window 2 is in the closed state.

  As illustrated in FIGS. 8A and 8B, in the third embodiment, when the window 2 to which the RF tag 10 is attached is in the open state, the wireless communication between the RF tag 10 and the alarm device 11 is inhibited. A band-shaped radio wave blocking member 13 is disposed. Thus, by arranging the radio wave blocking member 13, the RF tag 10 attached to the opened window 2 transmits radio waves. For the radio wave blocking member 13, a material having a radio wave shielding function can be used. It is preferable to use an aluminum plate having a relatively low specific gravity as the radio wave blocking member.

  By attaching the radio wave blocking member 13 as illustrated in FIG. 8, when the window 2 is in the closed state, the carrier wave transmitted by the alarm device 11 reaches the RF tag 10 attached to the window 2 and attached to the window 2 The RF tag 10 transmits the radio wave on which the tag identifier is modulated and loaded, and the reader / writer unit 111 of the alarm device 11 can receive the radio wave transmitted by the RF tag 10. On the other hand, when the window 2 is open, the carrier wave transmitted by the alarm device 11 does not reach the RF tag 10 attached to the window 2. Therefore, the RF tag 10 attached to the window 2 modulates the tag identifier. The reader / writer unit 111 of the alarm device 11 can not receive the radio wave transmitted by the RF tag 10 without transmitting the radio wave loaded thereon.

  Although only the case of the outer window 21 is described in FIG. 8, the inner window 20 can be configured in the same manner.

  The process of determining the open / close state of the window 2 in the third embodiment will be described. FIG. 9 is a diagram for explaining the process of determining the open / close state of the window 2 in the third embodiment.

  The reader / writer unit 111 of the alarm device 11 acquires, as the reception status of the radio wave transmitted by the RF tag 10 receiving the command, the tag identifier placed on the radio wave transmitted by the RF tag 10 receiving the command (S30).

  The alarm control unit 110 of the alarm device 11 executes a process of determining whether the reader / writer unit 111 has acquired all the tag identifiers registered in the alarm control unit 110 of the alarm device 11 (S31). The process branches according to the result (S32). As in the first and second embodiments, the tag identifier stored in the RF tag 10 used in the security alarm device 1 is registered in advance in the alarm control unit 110 of the alarm device 11 according to the third embodiment.

  When the reader / writer unit 111 acquires all tag identifiers registered in the alarm control unit 110 of the alarm device 11, the carrier wave has reached all of the RF tags 10 attached to the window 2, and an alarm is generated. The alarm control unit 110 of the device 11 determines that all the windows 2 to which the RF tag 10 is attached is closed (S33), and the procedure of FIG. 9 ends.

  In addition, including the case where the reader / writer unit 111 can not acquire any tag identifier, it is attached to the window 2 when all the tag identifiers registered in the alarm control unit 110 of the alarm device 11 are not acquired. The carrier wave does not reach at least one of the attached RF tags 10, and at least one of the windows 2 attached with the RF tags 10 is determined to be open (S34), and the procedure of FIG. 9 ends. .

1 Security Alarm Device 10 RF Tag 11 Alarm Device 110 Alarm Control Unit 111 Reader / Writer Unit 112 Reader / Writer Antenna 113 Alarm Unit 2 Window 20 Inside Window 21 Outside Window

Claims (5)

It has an RF tag attached to the opening and closing part of the fixture, and an alarm device that wirelessly communicates with the RF tag,
The alarm device has an antenna used for wireless communication with the RF tag, transmits a carrier wave that supplies power to the RF tag, and performs a process of acquiring the reception status of radio waves transmitted by the RF tag. And an alarm control unit performing processing of acquiring from the reader / writer unit the reception status of the radio wave transmitted by the RF tag, and determining the open / close state of a fixture attached with the RF tag transmitted the radio wave, Security alarm device characterized by. The reader / writer unit of the alarm device acquires the received radio wave intensity when the radio wave transmitted by the RF tag is received as a reception state, and the alarm control unit of the alarm device determines the open / close state of a fixture The difference between the received radio wave intensity when the fixture is in the closed state and the received radio wave intensity acquired by the reader / writer unit is calculated, and when the difference is greater than the threshold, the fixture with the RF tag attached is opened Perform determination processing, characterized in that
A security alarm device according to claim 1. A radio wave blocking member disposed to block a carrier wave reaching the RF tag in any one of an open state and a closed state;
When the RF tag receives a command to read out the tag identifier, it sends out a radio wave carrying the tag identifier stored in the RF tag,
After transmitting the carrier wave carrying the command, the reader / writer unit of the alarm device acquires a tag identifier carried on the radio wave as a reception status of the radio wave transmitted by the RF tag, and The alarm control unit performs processing of determining the open / close state of the fixture based on whether or not the tag identifier registered in the alarm control unit has been acquired.
A security alarm device according to claim 1. The radio wave blocking member is arranged to block a carrier wave that reaches the RF tag when a fixture attached with the RF tag is closed,
The reader / writer unit of the alarm device acquires, as a reception status, a tag identifier placed on a radio wave transmitted by the RF tag, and the alarm control unit performs the alarm control as processing for determining the open / close state of a fixture. When the reader / writer unit acquires a tag identifier registered in a unit, processing is performed to determine that the fixture on which the RF tag is attached is in an open state,
A security alarm device according to claim 3. The radio wave blocking member is disposed to block a carrier wave that reaches the RF tag when a fixture attached with the RF tag is in an open state,
The reader / writer unit of the alarm device acquires, as a reception status, a tag identifier placed on a radio wave transmitted by the RF tag, and the alarm control unit performs the alarm control as processing for determining the open / close state of a fixture. The crime prevention according to claim 3, characterized in that when the reader / writer unit does not acquire the tag identifier registered in the unit, it is determined that the fixture attached with the RF tag is in the open state. Alarm device.