JP4112454B2 - Glass breakage detector and security glass - Google Patents

Description

  The present invention relates to a glass breakage detection device that detects fraudulent actions involving the destruction of glass, and to a crime prevention glass used in a glass breakage detection apparatus in order to prevent fraudulent acts from the outside.

  Conventionally, a crime prevention device disclosed in the following Patent Document 1 (Japanese Patent Laid-Open No. 2002-352342) is known. As shown in FIG. 10, this security device forms a metal conductive layer 54 on one side of a transparent insulating resin layer 53 to prepare a resin material 52 with a conductive layer, and laminates two of them to conduct electricity on both sides. Layers 54 are arranged, and a glass plate 55 is laminated so as to be in contact with each conductive layer 54 to form a security glass 56, and a terminal 58 connected to each conductive layer 54 is connected to a capacitance detector 57. is doing. The capacitance detector 57 includes an alarm 59 that converts the alarm signal into a sound signal or an optical signal. Note that the end portion of the security glass 56 is fixed by a frame 60.

  In the crime prevention device disclosed in Patent Document 1 described above, two laminated conductive films 54 and 54 form a capacitor. Then, in order to detect the capacitance of the capacitor formed on the glass surface, one end of the lead wire is connected to the two conductive films 54, 54, and the other end of the lead wire is connected to the capacitance detector 57. Connected. As a result, the capacitance detector 57 detects the capacitance of the capacitor by the two conductive films 54 and 54 that change by approaching or contacting the security glass 56.

  In addition, as a device that does not use a lead wire drawn from the conductive film described above, a human body detection device that detects a human body approaching glass is disclosed in Patent Document 2 (Japanese Patent No. 2952642). As shown in FIG. 11, this human body detection device is formed by interposing a thin transparent conductive material 71 serving as a human body detection unit between plate glasses 72 and 73. A terminal portion is formed at the end of the transparent conductor 71, and an FPC (flexible printed wiring board) 74 is connected to the terminal portion. A flat coil 75 is formed on the end of the FPC 74 by a conductive pattern, and the transparent conductor 71 is connected to one end of the coil 75. The other end of the coil 75 extends to the back surface through a through hole and is connected to another conductive line. This conductive line ends at the middle part of the FPC 74. A slave unit 78 is attached to the window frame (fixed portion) side, and an oscillation circuit 81 is built in the slave unit 78. A coil 76 formed of the same FPC 77 as described above is connected to the resonance circuit of the oscillation circuit 81, and together with the transparent conductor 71, an equivalent circuit shown in FIG. The coil 76 is disposed to face the coil 75 with a small space. The coil 75 on the human body detection unit side and the coil 76 on the oscillation circuit side are electromagnetically coupled to form an electromagnetic coupling unit. The frequency signal processed in the slave unit 78 is superimposed on a power source line (line for supplying power to the circuit in the slave unit 78) 79 and sent to the master unit 80 installed separately.

In the human body detection device disclosed in Patent Document 2 described above, the presence or absence of human body detection is determined based on the change in capacitance accompanying the approach of the human body to the glass surface. According to this human body detection device, the detection device main body and the conductive film are not in contact with each other by using a pair of coils 75 and 76. For this reason, the installation work of the apparatus is facilitated and the structure is also aesthetically pleasing. Further, Patent Document 2 describes that two transparent conductors may be arranged between glasses or on the surface of glass at intervals, and the two transparent conductors may be connected to both ends of the coil. Yes.
JP 2002-352342 A Japanese Patent No. 2952642

However, in the configuration of FIG. 10 disclosed in Patent Document 1, it is necessary to connect the lead wires drawn out from the conductive layers 54 and 54 to the main body of the capacitance detector 57. For this reason, labor is required for wiring, and the installation work of the sensor becomes large. And since the lead wire was pulled out from the glass frame, it was unpreferable aesthetically. Further, when a small breakage such as a crack occurs in the glass, the capacitance change of the capacitor due to the conductive films 54 and 54 formed in the glass hardly occurs, and thus it cannot be detected until the glass is broken. It was difficult to detect early intrusion with glass breakage.
On the other hand, in the human body detection device that does not use the lead wire of FIG. 11 disclosed in Patent Document 2, when the equivalent circuit shown in FIG. 12 is formed by one conductive film (transparent conductor 71), the conductive film is formed. The stray capacitance of the capacitor to be monitored will be monitored. However, this stray capacitance is easily affected by the environment around the device such as temperature and humidity. For this reason, it has been difficult to perform stable detection due to malfunction or the like. When two conductive films (transparent conductors 71 and 71) are opposed to each other to form an equivalent circuit, the two conductive films are provided on different glass surfaces, and the ends of these conductive films are connected to the coil. There is a need. For this reason, there is a problem that the installation work is complicated, accompanied by a difficult work of wiring the two conductive films provided apart from each other with the coil.

  Therefore, the present invention has been made in view of the above problems, and glass breakage detection that can reliably detect fraudulent acts involving glass breakage without being influenced by the surrounding environment and can simplify installation work. It aims at providing a device and crime prevention glass.

The glass breakage detection apparatus according to claim 1, wherein the glass breakage detection apparatus detects a breakage of the glass by forming a conductive film on the glass surface.
A first conductive film formed on one glass surface;
A second conductive film which is formed by dividing into multiple to the glass surface opposite to the first conductive film,
A change in capacitance between the first conductive film and the second conductive film is detected by being connected to each of the divided second conductive films without being connected to the first conductive film. A detection unit;
It is provided with.

  The glass breakage detection device according to claim 2 is the glass breakage detection device according to claim 1, wherein the first conductive film is formed in a continuous line shape with respect to the one glass surface. Features.

  The glass breakage detection device according to claim 3 is the glass breakage detection device according to claim 1, wherein the first conductive film is divided into a plurality of portions on the one glass surface, and at least Adjacent portions are opposed to each other so as to overlap the second conductive film.

The glass breakage detection apparatus according to claim 4 is the glass breakage detection apparatus according to any one of claims 1 to 3, wherein the detection unit includes a pair of opposing coils,
A resonance frequency detector connected to one of the pair of coils,
The other coil of the pair of coils is formed on the same plane as the second conductive film, and each of the second conductive films is connected to both ends of the other coil.

The crime prevention glass described in claim 5 is a crime prevention glass used for a glass breakage detection device having a detection unit for detecting a change in capacitance of a conductive film formed to face a glass surface,
A first conductive film formed on one of the glass surface,
To face the first conductive layer to the glass surface and a second conductive film which is formed by dividing into a plurality,
The first conductive film is not connected to the detection unit, and each of the divided second conductive films is connected to the detection unit .

The crime prevention glass described in claim 6 is the equivalent crime prevention glass according to claim 5 , further comprising a coil connecting each of the divided second conductive films to both ends, and having a plurality of capacitors. Form the
A change in resonance frequency corresponding to a change in capacitance of the plurality of capacitors can be detected by the detection unit .

  Since the glass breakage detection apparatus of the present invention forms the first conductive film on one glass surface (for example, the outdoor side) and forms the second conductive film divided into a plurality on the other glass surface (for example, the indoor side). The lead wire can be drawn out only from the second conductive film divided into a plurality of parts, and the installation work of the apparatus including the detection unit can be simplified.

  If the first conductive film facing the second conductive film divided into a plurality of parts is formed in a continuous line shape, the capacitance of the first conductive film and the second conductive film even when the glass is cracked Changes, so that the detection accuracy can be improved.

  If each of the first conductive film and the second conductive film is divided into a plurality of parts so that a part of the adjacent conductive films overlaps each other, the plurality of divided first conductive films and second conductive films are formed. Thus, an equivalent circuit having a plurality of capacitors can be formed, and even a slight breakage of glass can be detected. Thereby, further improvement in detection accuracy can be expected, and it becomes possible to detect fraudulent actions accompanied by glass breakage at an early stage, thereby dramatically improving the crime prevention performance.

  If the coil is formed on the same plane as the second conductive film and the coil and the second conductive film are connected, the glass breakage can be detected in a non-contact manner simply by arranging the coil on the glass surface. In addition, the coil can be easily installed without taking a place on the same plane together with the second conductive film by a generally known method such as a vapor deposition method, and can be downsized.

  Crime prevention suitable for detection of glass breakage by forming the first conductive film on one glass surface and forming the second conductive film connected to a part of the detection part in a plurality of parts on the other glass surface Glass can be easily manufactured. In addition, if each of the second conductive films is connected to the end of the coil to form an equivalent circuit having a plurality of capacitors, a sensor unit for detecting glass breakage can be formed integrally with the glass itself.

  The best mode of the present invention will be specifically described below with reference to the drawings. FIG. 1A is a block diagram showing a first embodiment of a glass breakage detecting apparatus including a crime prevention glass according to the present invention, FIG. 1B is a diagram showing an equivalent circuit of FIG. 1A, and FIG. FIG. 3 and FIG. 4 are diagrams showing a specific example of a resonance frequency detection unit, and FIG. 5 (a) is a diagram showing a glass breakage detection apparatus including a crime prevention glass according to the present invention. FIG. 5 (b) is a diagram showing an equivalent circuit of FIG. 5 (a), FIG. 6 (a) is a diagram showing an example at the time of glass breakage in the second mode, and FIG. 6 (b). Is a diagram showing an equivalent circuit at the time of glass breakage in FIG. 6 (a), FIG. 7 (a) is a configuration diagram showing a third embodiment of a glass breakage detecting device including a crime prevention glass according to the present invention, and FIG. FIG. 7 is a diagram showing an equivalent circuit of FIG. 7A, FIG. 8 is a partial cross-sectional view of the security glass of FIG. 7A, and FIG. Shows an example of a case, FIG. 9 (b) is a diagram showing an equivalent circuit at the time of glass fracture in FIG. 9 (a).

  The glass breakage detection apparatus including the crime prevention glass according to the present invention forms a conductive film with an intermediate film sandwiched between glass surfaces such as laminated glass, for example, and splits one conductive film to equivalently form a plurality of capacitors. The presence or absence of glass breakage is detected based on a change in the capacitance of the capacitor due to the conductive film that is formed and broken simultaneously with the glass when the glass is broken.

  As shown to Fig.1 (a), the glass breakage detection apparatus 1 of 1st form is comprised roughly by the crime prevention glass 2 and the sensor main body 10. FIG. In this example, laminated glass is used for the security glass 2. More specifically, as shown in FIG. 1 (a), the security glass 2 is between the first glass 3 (for example, the side facing the outdoors) and the second glass 4 (for example, the side facing the indoors). Further, a laminated glass is formed through the intermediate film 7. The intermediate film 7 is formed of, for example, a transparent polymer film or the like, and a first conductive film 5 and a second conductive film 6 are formed between the intermediate film 7 and the respective glasses 3 and 4. In addition, as the glass of the crime prevention glass 2, various glasses, such as a tempered glass excellent in crime prevention property, can be used, for example.

  The first conductive film 5 is formed on the glass surface between the surface on the indoor side of the first glass 3 and the intermediate film 7, and is formed to have approximately the same size as the surface of the first glass 3. The second conductive film 6 is formed on the glass surface between the surface on the outdoor side of the second glass 4 and the intermediate film 7 and is divided into a plurality of parts. In the example of FIG. 1, the second conductive film 6 is divided into two parts. The second conductive film 6 is formed of the same material as the first conductive film 5. The conductive films 5 and 6 are preferably aesthetically transparent. For example, ITO (Indium Tin Oxide) is used. The conductive films 5 and 6 are formed by a technique such as a PVD (Physical Vapor Deposition) method such as vacuum deposition or sputtering, ion plating, CVD (chemical vapor deposition), etching (wet or dry), for example.

  A coil 8 is spirally formed, for example, on a glass surface on the same plane as the second conductive film 6 (upper left corner of FIG. 1). The coil 8 has one end connected to one side of the second conductive film 6 and the other end connected to the other second conductive film 6 via an insulating layer (not shown), for example.

  As described above, in the glass breakage detection apparatus according to the first embodiment, the first conductive film 5 and the second conductive film 6 are formed to face the glass surface with the intermediate film 7 interposed therebetween. The second conductive film 6 is divided into two parts, and the divided second conductive film 6 is connected to both ends of the coil 8 to form an equivalent circuit shown in FIG. Thereby, when any change occurs in the structure of the equivalent circuit shown in FIG. 1B, an abnormality is detected by measuring a change in the capacitance of the capacitor.

  Next, the configuration of the glass breakage detection unit 11 will be described with reference to FIGS. 1 and 2. In the security glass 2, the sensor unit 12 is formed by the first conductive film 5, the second conductive film 6, and the coil 8 described above. As shown by the broken-line circles in FIGS. 1 and 2, the coil 9 is provided in a pair with the coil 8 of the sensor unit 12. A sensor body 10 including a resonance frequency detection unit 13 and a calculation unit 14 is installed near the glass having the sensor unit 12, and both ends of the coil 9 are connected to the resonance frequency detection unit 13. The glass breakage detection unit 11 includes a coil 8, a coil 9, a resonance frequency detection unit 13, and a calculation unit 14 of the sensor unit 12, as indicated by a one-dot chain line in FIG. 2. The resonance frequency detector 13 detects a resonance frequency corresponding to a change in the capacitance of the capacitor by the first conductive film 5 and the second conductive film 6 via the electromagnetically coupled coils 8 and 9. The calculation unit 14 determines whether the security glass 2 is abnormal based on the resonance frequency detected by the resonance frequency detection unit 13.

  Next, the operation up to detection of glass breakage will be described. First, when the first conductive film 5 is lost due to a part of the glass of the security glass 2 being broken, the electrode area of the capacitor formed by the first conductive film 5 and the second conductive film 6 changes. Along with this, the resonance frequency detected by the resonance frequency detector 13 in the sensor body 10 changes. When the resonance frequency detected by the resonance frequency detection unit 13 is input, the calculation unit 14 compares the amount of change in the resonance frequency with the noise level. When the amount of change in the resonance frequency is greater than the noise level, Determine.

  Note that the calculation unit 13 is not limited to the comparison with the noise level, and may have a configuration in which a threshold is set in advance and a case where the threshold is exceeded is determined as glass breakage. Further, when the window is opened, the distance between the coil 8 of the sensor unit 12 and the coil 9 of the sensor body 10 changes, and the resonance frequency changes accordingly, and an abnormality of the security glass 2 is detected.

  Here, a specific configuration of the resonance frequency detection unit 13 will be described with reference to FIGS. 3 and 4. 3 includes a coil 9 for electromagnetically coupling with the coil 8 of the sensor unit 12, an oscillation circuit 15, and a low-pass filter (hereinafter abbreviated as LPF) 16. The oscillation circuit 15 is set to an appropriate oscillation frequency f in consideration of the resonance frequency of the sensor unit 12 and the positional relationship between the sensor unit 12 and the sensor body 10. In this state, the coil 8 and the coil 9 of the sensor unit 12 are electromagnetically coupled, the output of the oscillation circuit 15 is absorbed by the sensor unit 12 through the pair of coils 8 and 9, and the amplitude of the signal input to the LPF 16 has a certain value. Take v1. The LPF 16 smoothes the input AC signal (amplitude v <b> 1) and outputs it as a DC signal that can be processed by the calculation unit 14.

  In the resonance frequency detection unit 13 configured as described above, when the glass is broken or broken, the first conductive film 5 or the second conductive film 6 provided on the glass surface is missing and the resonance frequency of the sensor unit 12 changes, or a window Is opened and the electromagnetic coupling between the coil 8 of the sensor unit 12 and the coil 9 of the sensor body 10 is lost, the portion of the output of the oscillation circuit 15 that is absorbed through the coil is reduced or lost. For this reason, the amplitude value of the signal input to the LPF 16 takes v2 larger than v1 in the normal time. The LPF 16 smoothes the input AC signal (amplitude value v2) and outputs it as a DC signal that can be processed by the computing unit 14. The calculation unit 14 determines that some abnormality such as breakage or destruction of the glass or opening of the window has occurred by detecting that the signal input from the LPF 16 changes from v1 to v2.

  The resonance frequency detector 13 shown in FIG. 4 includes a coil 9 for electromagnetic coupling with the coil 8 of the sensor unit 12, a VCO (voltage controlled oscillator) 17 that outputs an output signal similar to the resonance frequency of the sensor unit 12, A control circuit 18 that controls the VCO 17 so that the frequency of the output signal of the VCO 17 becomes the resonance frequency of the sensor unit 12 and outputs a VCO control voltage that also serves as an output to the arithmetic unit 14 is provided.

  In the resonance frequency detection unit 13 having the above-described configuration, the output voltage of the control circuit 18 takes a constant value when the window is closed and there is no abnormality in the glass, but if any abnormality occurs in the glass or the window is opened. The resonance frequency changes. For this reason, the output voltage of the control circuit 18 also changes. The calculation unit 14 determines that some abnormality such as breakage or destruction of the glass or opening of the window has occurred due to a change in the control voltage output from the control circuit 18.

  According to the first embodiment described above, the presence or absence of glass breakage can be detected stably at all times without being influenced by surrounding environmental changes. Further, since the coil 8 is formed on the same surface as the second conductive film 6, it is not necessary to route the lead wire, and the appearance is improved. When the equivalent circuit shown in FIG. 1B is formed by the first conductive film 5, the second conductive film 6, and the coil 8, the coil 8 is connected to the second conductive film 6 on the same plane. Thus, it is not necessary to connect each of the conductive films formed separately to the coil, and the wiring work can be performed on one surface of the glass surface, so that the structure can be simplified and the installation work can be simplified.

  Next, a glass breakage detection apparatus according to a second embodiment will be described with reference to FIGS. 5 and 6. The glass breakage detection apparatus 1 of the second form is one in which the first conductive film 5 formed on the security glass 2 is continuously formed in a single line. In addition, the same number is attached | subjected and demonstrated to the component same as a 1st form. Moreover, although the structure shown in FIG.3 and FIG.4 is employ | adopted as the glass breakage detection part 13, description is abbreviate | omitted here.

  As shown to Fig.5 (a), the glass breakage detection apparatus 1 of the 2nd form is schematically comprised by the security glass 2 and the sensor main body 10. FIG. In this example, laminated glass is used for the security glass 2. More specifically, as shown in FIG. 5 (a), the security glass 2 is between the first glass 3 (for example, the side facing the outdoors) and the second glass 4 (for example, the side facing the indoors). Further, a laminated glass is formed through the intermediate film 7. The intermediate film 7 is formed of, for example, a transparent polymer film, and a first conductive film 5A (5) and a second conductive film 6A (6) are formed between the intermediate film 7 and the respective glasses 3 and 4. Has been. In addition, as the glass of the crime prevention glass 2, various glasses, such as a tempered glass excellent in crime prevention property, can be used, for example.

  The first conductive film 5 </ b> A (5) is formed on the glass surface between the indoor side surface of the first glass 3 and the intermediate film 7, and is formed linearly over almost the entire surface of the first glass 3. More specifically, the second conductive film 5A (5) is formed as one continuous linear conductive film. In the example of FIG. 5 (a), one conductive film forming the second conductive film 5A (5) is folded at the left and right ends of the glass surface so that slits are inserted at predetermined intervals in the height direction of the glass. The glass surface is continuously formed in a wave shape from the upper left end to the lower left end. Note that the first conductive film 5A (5) is not limited to a wave shape as shown in FIG. For example, it is possible to form the first conductive film 5A (5) in a spiral shape over almost the entire glass surface.

  The second conductive film 6A (6) is formed on the glass surface between the surface on the outdoor side of the second glass 4 and the intermediate film 7, and is divided into a plurality of parts. In the example of FIG. 5A, the second conductive film 6A (6) is formed by being divided into two. The second conductive film 6A (6) is formed of the same material as the first conductive film 5A (5). These conductive films 5A (5) and 6A (6) are preferably aesthetically transparent. For example, ITO (Indium Tin Oxide) or the like is used. These conductive films 5A (5) and 6A (6) are formed by, for example, PVD (Physical Vapor Deposition) methods such as vacuum deposition and sputtering, ion plating, CVD (chemical vapor deposition), etching (wet, dry), and the like. To form.

  A coil 8 is spirally formed, for example, on a glass surface on the same plane as the second conductive film 6 (upper left corner of FIG. 5A). One end of the coil 8 is connected to one of the second conductive films 6A (6), and the other end is connected to the other second conductive film 6A (6) through an insulating layer (not shown), for example.

  Thus, in the glass breakage detection apparatus of the second embodiment, the first conductive film 5A (5) and the second conductive film 6A (6) are formed to face the glass surface with the intermediate film 7 interposed therebetween. Then, the first conductive film 5A (5) is formed in a continuous linear shape over almost the entire glass surface, and the second conductive film 6A (6) facing the first conductive film 5A (5) is divided into two, The divided second conductive film 6A (6) is connected to both ends of the coil 8 to form an equivalent circuit shown in FIG. As a result, when any change occurs in the structure of the equivalent circuit shown in FIG. 5B, an abnormality is detected by measuring a change in the capacitance of the capacitor.

  Next, in the second embodiment, a case where the glass surface is damaged will be described with reference to FIGS. 6 (a) and 6 (b).

  As shown in FIG. 6A, when the first conductive film 5A (5) is cut and missing because a part of the glass of the security glass 2 is broken by cracks or the like, the first conductive film 5A (5 ) And the second conductive film 6A (6), the electrode area of the capacitor changes, and the configuration of the equivalent circuit changes as shown in FIG. 6B. Along with this, the resonance frequency detected by the resonance frequency detector 13 in the sensor body 10 changes. When the resonance frequency detected by the resonance frequency detection unit 13 is input, the calculation unit 14 compares the amount of change in the resonance frequency with the noise level. When the amount of change in the resonance frequency is greater than the noise level, Determine. The calculation unit 13 is not limited to the comparison with the noise level, and may be configured to determine that the glass is broken when a threshold is set in advance and the threshold is exceeded. Further, when the window is opened, the distance between the coil 8 of the sensor unit 12 and the coil 9 of the sensor body 10 changes, and accordingly, the resonance frequency changes and the abnormality of the security glass 2 is detected.

  According to the second embodiment described above, the same effect as that of the first embodiment can be obtained, and since the first conductive film 5A (5) is continuously formed in a linear shape, even a slight damage to the glass can be accurately performed. Can be detected. Thereby, compared with a 1st form, detection accuracy can improve and a crime prevention effect can be heightened.

  Next, a glass breakage detection apparatus according to a third embodiment will be described with reference to FIGS. In the glass breakage detection apparatus 1 of the third form, the first conductive film 5 and the second conductive film 6 formed on the crime prevention glass 2 are divided into a plurality of parts and are formed in a dot matrix so as to face each other so as to overlap each other. Is. In addition, the same number is attached | subjected and demonstrated to the component same as a 1st form. Moreover, although the structure shown in FIG.3 and FIG.4 is employ | adopted as the glass breakage detection part 13, description is abbreviate | omitted here.

  As shown to Fig.7 (a), the glass breakage detection apparatus 1 of the 3rd form is roughly comprised by the security glass 2 and the sensor main body 10. As shown in FIG. In this example, laminated glass is used for the security glass 2. More specifically, as shown in FIG. 7A, the security glass 2 is between the first glass 3 (for example, the side facing the outdoors) and the second glass 4 (for example, the side facing the indoors). Further, a laminated glass is formed through the intermediate film 7. The intermediate film 7 is formed of, for example, a transparent polymer film, and a first conductive film 5B (5) and a second conductive film 6B (6) are formed between the intermediate film 7 and the respective glasses 3 and 4. Has been. In addition, as the glass of the crime prevention glass 2, various glasses, such as a tempered glass excellent in crime prevention property, can be used, for example.

  The first conductive film 5B (5) is formed on the glass surface between the indoor side surface of the first glass 3 and the intermediate film 7, and is divided into a plurality of dot matrices on the substantially entire surface of the first glass 3. Is formed. The second conductive film 6B (6) is formed on the glass surface between the outdoor side surface of the second glass 4 and the intermediate film 7, so that a part adjacent to the first conductive film 5B (5) overlaps. It is divided into a plurality of dot matrix shapes. As shown in FIG. 7, the second conductive film 6B (6) has an upper end portion serving as a first lead-out portion 6a, and the first lead-out portion 6a is the uppermost end portion of the first conductive film 5B (5). It is formed in a flat plate shape so as to overlap a part of all the first conductive films 5B (5). Further, as shown in FIG. 7, the left end portion of the second conductive film 6B (6) forms the second lead-out portion 6b, and this second lead-out portion 6b is the entire bottom end portion of the first conductive film 5B (5). The first conductive film 5 </ b> B (5) overlaps a part of the first conductive film 5 </ b> B (5) and is formed in an L shape so as to be led out to the position close to the coil 8. The second conductive film 6B (6) is formed of the same material as the first conductive film 5B (5). The conductive films 5B (5) and 6B (6) are preferably aesthetically transparent, and for example, ITO (Indium Tin Oxide) is used. These conductive films 5B (5) and 6B (6) may be formed by, for example, PVD (Physical Vapor Deposition) methods such as vacuum vapor deposition and sputtering, ion plating, CVD (chemical vapor deposition), etching (wet, dry), and the like. To form.

  A coil 8 is formed, for example, in a spiral shape on a glass surface on the same plane as the second conductive film 6B (6) (upper left corner of FIG. 7A). One end of the coil 8 is connected to the planar first lead-out portion 6a of the second conductive film 6B (6), and the other end is connected to the L of the second conductive film 6B (6) via an insulating layer (not shown), for example. The second lead-out portion 6b having a character shape is connected.

  Thus, in the glass breakage detection apparatus of the third embodiment, as shown in FIGS. 7 and 8, a part of the first conductive film 5B (5) and the second conductive film 6B (6) with the intermediate film 7 interposed therebetween. Are arranged in a dot matrix so as to face each other. Thereby, a plurality of capacitors are equivalently connected in series in the height direction of the glass surface (the arrow Y direction in FIG. 7). A plurality of columns of capacitors connected in series are connected in parallel between the first derivation unit 6 a and the second derivation unit 6 b (in the direction of arrow X in FIG. 7), and the first derivation unit 6 a is connected to one end of the coil 8. The second lead-out part 6 b is connected to the other end of the coil 8. Thereby, the equivalent circuit shown in FIG. 1B is formed. When any change occurs in the structure of the equivalent circuit shown in FIG. 7B, the presence or absence of abnormality is detected by measuring the change in the capacitance of the capacitor.

  Next, in the third embodiment, the case where the glass surface is damaged will be described with reference to FIGS. 9 (a) and 9 (b).

  As shown in FIG. 9A, if the first conductive film 5B (5) or the second conductive film 6B (6) is missing due to a part of the glass of the security glass 2 being broken by cracks or the like, the first The number of capacitors formed by the conductive film 5B (5) and the second conductive film 6B (6) changes. Along with this, the resonance frequency detected by the resonance frequency detector 13 in the sensor body 10 changes. When the resonance frequency detected by the resonance frequency detection unit 13 is input, the calculation unit 14 compares the amount of change in the resonance frequency with the noise level. When the amount of change in the resonance frequency is greater than the noise level, Determine. Note that the calculation unit 13 is not limited to the comparison with the noise level, and may be configured such that a threshold is set in advance and the glass is determined to be broken when the threshold is exceeded. Further, when the window is opened, the distance between the coil 8 of the sensor unit 12 and the coil 9 of the sensor body 10 changes, and accordingly, the resonance frequency changes and the abnormality of the security glass 2 is detected.

  According to the 3rd form mentioned above, while having the same effect as the 1st form and the 2nd form, the 1st conductive film 5B (5) and the 2nd conductive film 6B (6) are overlapped at least partially. Since a plurality of capacitors are formed so as to be equivalently opposed to each other, the glass is divided into a plurality of parts, so that slight damage to the glass can be accurately detected. Thereby, compared with the 1st, 2nd form, detection accuracy further improves and a crime prevention effect can be improved greatly. And by employ | adopting the structure of each form mentioned above, the crime prevention glass suitable for the detection of glass destruction can be manufactured easily, and the sensor part which detects the change of an electrostatic capacitance can be integrally formed in glass itself.

  By the way, in the form mentioned above, although the example which used the laminated glass for the crime prevention glass 2 was demonstrated, not only a laminated glass but the 1st electrically conductive film 5 is formed in one surface of one glass, and the other surface is formed. Even when the second conductive film 6 (6A, 6B) is formed by being divided into a plurality of parts, the same effect can be obtained. In this example, the window glass is taken as an example, but it can be used in places where security measures are required, such as a door showcase, a glass portion of a show window, a case of an exhibit in a museum or a jewelry store, etc. . Thereby, it acts as the crime prevention glass 2, and can improve a crime prevention effect drastically.

  In the first to third embodiments, the first conductive film 5 (5A, 5B) is formed of the same material as the second conductive film 6 (6A, 6B). It is possible to use different materials depending on the properties of the conductive film material and the usage environment.

  Further, the capacitor composed of the first conductive film 5 (5A, 5B) and the second conductive film 6 (6A, 6B) formed on the glass surface, and the resonance frequency detector 13 (13A, 13B) include the coils 8, 9 However, when there is no problem in drawing out the lead wire from the glass, the capacitor composed of the first conductive film 5 (5A, 5B) and the second conductive film 6 (6A, 6B). The resonance frequency detector 13 (13A, 13B) may be directly connected by a lead wire. In this case, the resonance frequency detector 13 (13A, 13B) preferably uses a capacitance detection circuit. Even in such a case, slight glass breakage, cracks, and the like can be detected with high sensitivity.

  In the third embodiment, the shape of the dot matrix-like conductive film formed by the first conductive film 5B (5) and the second conductive film 6B (6) is a quadrangle, but is not limited to a quadrangle, for example, other polygonal shapes or circles. Various shapes such as shapes can be used in accordance with the application. Thereby, while having the same effect as each form mentioned above, the convenience improves, without limiting a use range. In this example, the case where the conductive film is transparent is described as an example. However, the present invention is not limited thereto, and a colored or opaque conductive film may be used depending on the application.

  The combination of the first conductive film and the second conductive film that can be adopted in this example is not limited to the one shown in the figure, and includes a reversed configuration, and a plurality of capacitors are equivalent by at least the first conductive film and the second conductive film. As long as it is configured in a general manner. For example, various combinations such as a combination of a linear conductive film, a combination of a plate-shaped conductive film and a linear conductive film, and a combination of a linear conductive film and a plurality of conductive films can be considered. Thereby, it is possible to constitute the best glass breakage detection device according to the use environment and application.

(A) It is a block diagram which shows the 1st form of the glass breakage detection apparatus containing the crime prevention glass which concerns on this invention. (B) It is a figure which shows the equivalent circuit of (a). It is a figure which shows the electrical constitution of the glass breakage detection apparatus which concerns on this invention. It is a figure which shows the specific example of the resonant frequency detection part of this invention. It is a figure which shows the specific example of the resonant frequency detection part of this invention. (A) It is a block diagram which shows the 2nd form of the glass breakage detection apparatus containing the crime prevention glass which concerns on this invention. (B) It is a figure which shows the equivalent circuit of (a). (A) It is a figure which shows the example at the time of the glass break in a 2nd form. (B) It is a figure which shows the equivalent circuit at the time of the glass destruction of (a). (A) It is a block diagram which shows the 3rd form of the glass breakage detection apparatus containing the crime prevention glass which concerns on this invention. (B) It is a figure which shows the equivalent circuit of (a). It is a fragmentary sectional view of the crime prevention glass of Fig.7 (a). (A) It is a figure which shows the example at the time of the glass break in 3rd form. (B) It is a figure which shows the equivalent circuit at the time of the glass destruction of (a). It is a figure which shows the conventional glass breakage detection apparatus. It is a figure which shows the conventional glass breakage detection apparatus. It is a figure which shows the equivalent circuit of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Glass breakage detection apparatus 2 Security glass 3 1st glass 4 2nd glass 5, 5A, 5B 1st electrically conductive film 6, 6A, 6B 2nd electrically conductive film 6a 1st derivation | leading-out part 6b 2nd derivation | leading-out part 7 Intermediate film 8 Coil 9 Coil 10 Sensor body

Claims (6)

In the glass breakage detection device that detects the breakage of the glass by forming a conductive film on the glass surface,
A first conductive film formed on one glass surface;
A second conductive film which is formed by dividing into multiple to the glass surface opposite to the first conductive film,
A change in capacitance between the first conductive film and the second conductive film is detected by being connected to each of the divided second conductive films without being connected to the first conductive film. A detection unit;
A glass breakage detection apparatus comprising: The glass breakage detection apparatus according to claim 1, wherein the first conductive film is formed in a continuous line shape with respect to the one glass surface. The first conductive film is formed by being divided into a plurality of parts on the one glass surface, and at least a part of the first conductive film faces the second conductive film so as to overlap each other. Item 2. The glass breakage detection device according to Item 1. The detection unit includes a pair of opposing coils,
A resonance frequency detector connected to one of the pair of coils,
The other coil of the pair of coils is formed on the same plane as the second conductive film, and each of the second conductive films is connected to both ends of the other coil. The glass breakage detection apparatus in any one of -3. A security glass used in a glass breakage detection device having a detection unit for detecting a change in capacitance of a conductive film formed to face a glass surface,
A first conductive film formed on one of the glass surface,
To face the first conductive layer to the glass surface and a second conductive film which is formed by dividing into a plurality,
The security glass, wherein the first conductive film is not connected to the detection unit, and each of the divided second conductive films is connected to the detection unit . Further comprising a coil connecting each of the second conductive film formed by the divided across, to form an equivalent circuit having a plurality of capacitors,
6. The security glass according to claim 5 , wherein a change in resonance frequency corresponding to a change in capacitance of the plurality of capacitors can be detected by the detection unit .

Images