JP2008158942A - Crime prevention sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crime prevention sensor which can be installed in a wide range for surely detecting the damage of an intrusion port configuring member by reducing erroneous operations. <P>SOLUTION: A crime prevention sensor 2 is provided with an elastically deformable sensor main body 20 with an elastomer and a spherical conductive filler blended in an almost single particle state by a high filling rate in the elastomer, and configured so that an electric resistance is increased according as deformation quantity is increased and electrodes 21A and 21B connected to the sensor main body 20 so that the electric resistance can be output, and this crime prevention sensor 2 is arranged at an intrusion port configuring member 90L configuring an intrusion port from the outside. The crime prevention sensor 2 is configured to detect the damage of the intrusion port configuring member 90L from the deformation of the sensor main body 20 accompanied with the deformation of the intrusion port configuring member 90L. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a security sensor for detecting breakage of an entry member constituting an entrance from outside and suppressing illegal entry into a building or the like.

  In recent years, illegal intrusions such as empty nests have occurred frequently, and awareness of crime prevention has increased. For example, in the case of a detached house, windows tend to be the entrance, and about 70% of the entry methods are broken glass. The tricks are various, such as breaking the window glass with a hammer, prying with a screwdriver, burning with a burner. As security measures against such glass breakage, attempts have been made to increase the strength of the window glass itself or to attach a security sensor to the window glass.

Examples of the security sensor include a magnet sensor that detects opening of a window, a door, etc., a vibration sensor that detects an impact when the glass is broken, a lead sensor that detects breakage of the glass by cutting the lead (for example, a patent) References 1-3).
JP 2002-42255 A Japanese Patent Laid-Open No. 2002-190069 Japanese Patent Laid-Open No. 11-39575

  In general, a magnet sensor detects the opening of a window, a door, etc., based on a change in the positional relationship between a reed switch part attached to a fixed part and a magnet part attached to a movable part that can be opened and closed such as a window and a door. . In other words, the magnet sensor operates only when the closed window or door is opened. For this reason, it cannot respond to breakage of the window glass without opening the window, which is not sufficient. On the other hand, a vibration sensor that detects acceleration of an applied impact may malfunction due to wind vibration or small vibration such as a pet hitting. Moreover, the kind of glass, thickness, etc. which can install a vibration sensor may be restrict | limited.

  The present invention has been made in view of such circumstances, and provides a security sensor that can be installed in a wide range, has few malfunctions, and can reliably detect breakage of an entry member. Let it be an issue.

  (1) The security sensor of the present invention has an elastomer and a spherical conductive filler blended in the elastomer in a substantially single particle state with a high filling rate, and the electrical resistance increases as the amount of deformation increases. An elastically deformable sensor body that increases, and an electrode that is connected to the sensor body and that can output the electrical resistance, and is disposed on an intrusion member constituting an intrusion port from the outside, Breakage of the intrusion port constituent member can be detected from deformation of the sensor body accompanying deformation of the intrusion port constituent member (corresponding to claim 1).

  For example, windows, entrances and the like are examples of entrances to buildings such as houses. When an intruder attempts to enter a building, intruders such as window glass, doors, and shutters constituting the intruder are often damaged. In this case, the entrance member is deformed due to breakage. Here, the security sensor of this invention is arrange | positioned at the intrusion opening structural member. And the sensor main body which an electrical resistance increases as a deformation amount increases is provided. Accordingly, when an illegal intruder breaks the entrance member and tries to enter a building or the like, the sensor body is deformed together with the entrance member. Based on the increase in the electrical resistance due to the deformation of the sensor body, the breakage of the entry member is detected. Thus, according to the security sensor of the present invention, illegal intrusion into a building or the like can be detected at an early stage. Further, since the breakage of the entry member is detected based on the increase in the electrical resistance due to the deformation of the sensor main body, it is unlikely to malfunction due to a small vibration not accompanied by the deformation of the sensor main body.

  Moreover, the sensor main body in the security sensor of the present invention (hereinafter referred to as “the sensor main body of the present invention” as appropriate) is elastically deformable and has an elastomer and a spherical conductive filler. In this specification, “elastomer” includes rubber and thermoplastic elastomer. The conductive filler is blended in the elastomer in a substantially single particle state and with a high filling rate. Here, the “substantially single particle state” means that 50% by weight or more when the total weight of the conductive filler is 100% by weight exists not in the form of aggregated secondary particles but in the form of single primary particles. It means that Further, “high filling rate” means that the conductive filler is blended in a state close to closest packing.

  As described above, when the conductive filler is blended in a substantially single particle state and at a high filling rate, a three-dimensional conductive path is formed by contact between the conductive fillers via the elastomer component (film). The Therefore, the sensor body in the present invention has high conductivity in a state where no load is applied (hereinafter referred to as “no-load state” as appropriate), in other words, in a natural state where the sensor body is not deformed. Note that “elastic deformation” in this specification includes all deformation due to compression, extension, bending, and the like.

  For example, a conventional pressure-sensitive conductive resin has a large electric resistance in an uncompressed state, and the electric resistance decreases when deformed by compression. This can be explained from the configuration of the pressure-sensitive conductive resin as follows. That is, the pressure sensitive conductive resin is composed of a resin and a conductive filler blended in the resin. Here, the filling rate of the conductive filler is low. For this reason, the conductive fillers are separated from each other in a no-load state. That is, in the no-load state, the electric resistance of the pressure sensitive conductive resin is large. On the other hand, when a load is applied and the pressure-sensitive conductive resin is deformed, the conductive fillers come into contact with each other to form a one-dimensional conductive path. This reduces the electrical resistance.

  On the other hand, the electrical resistance of the sensor body according to the present invention increases as the amount of deformation increases. The reason is considered as follows. FIG. 1 and FIG. 2 show changes in the conductive path of the sensor body according to the present invention before and after applying a load as a model. However, what is shown in FIGS. 1 and 2 is an example of the sensor main body, and the sensor main body, the shape and material of the conductive filler in the present invention are not limited at all.

  As shown in FIG. 1, in the sensor main body 100, most of the conductive fillers 102 are present in the state of primary particles in the elastomer 101. Moreover, the filling rate of the conductive filler 102 is high, and it is blended in a state close to closest packing. Thereby, in a no-load state, a three-dimensional conductive path P is formed in the sensor body 100 by the conductive filler 102. Therefore, in the no-load state, the electrical resistance of the sensor body 100 is small. On the other hand, as shown in FIG. 2, when a load is applied to the sensor main body 100, the sensor main body 100 is deformed (the dotted line frame in FIG. 2 indicates the no-load state in FIG. 1). Here, since the conductive filler 102 is blended in a state close to closest packing, there is almost no space where the conductive filler 102 can move. Therefore, when the sensor body 100 is deformed, the conductive fillers 102 repel each other, and the contact state between the conductive fillers 102 changes. As a result, the three-dimensional conductive path P collapses and the electrical resistance increases.

  The security sensor of the present invention having such a sensor body directly detects various deformations such as compression, expansion, bending, etc. occurring in the intrusion member based on an increase in electrical resistance of the sensor body output from the electrode. can do. Thereby, the breakage of the entry member can be detected. Here, “electric resistance can be output” means that electric resistance can be output directly or indirectly. That is, not only the case where the electrical resistance is directly output from the electrode but also the case where the other electrical quantity related to the electrical resistance such as voltage or current is output.

  The sensor body uses an elastomer as a base material. For this reason, the security sensor of the present invention is excellent in processability and has a high degree of freedom in shape design. Therefore, it can be arranged over a wide range regardless of the shape and size of the entry member. For example, if the crime prevention sensor of the present invention is arranged in a planar shape so as to cover the entrance member, the damage to the entrance member can be detected without fail. Further, by adjusting the number and arrangement of the electrodes connected to the sensor main body, finer sensing can be performed and the breakage position can be specified.

  In the security sensor of the present invention, the electrical resistance value in a no-load state can be set within a predetermined range by adjusting the type of elastomer and conductive filler, the filling rate of the conductive filler, and the like. For this reason, the range of the deformation amount that can be detected, that is, the detection range can be increased. In addition, since the increase behavior of the electric resistance with respect to the deformation amount can be adjusted, a desired response sensitivity can be realized.

  Moreover, the security sensor of the present invention has high conductivity in a no-load state. That is, the security sensor of the present invention is in a conductive state in a no-load state. For this reason, in a no-load state, operation diagnosis is easier as compared with a sensor having low conductivity (for example, a sensor using a conventional pressure-sensitive conductive resin). That is, in the case of a sensor having low conductivity in a no-load state, it is difficult to determine whether the sensor is normal or abnormal (for example, whether a circuit is disconnected) in the no-load state. For this reason, it is necessary to dare to apply a relatively high voltage to a sensor having low conductivity. Alternatively, it is necessary to check the energized state by operating the sensor on a trial basis. Therefore, the operation diagnosis is complicated. In contrast, the security sensor of the present invention has high conductivity in a no-load state. For this reason, it is easy to discriminate between normal and abnormal in a no-load state. Therefore, operation diagnosis is easy. For example, the operation diagnosis can be easily performed by operating the security sensor of the present invention in conjunction with locking of the entrance and the like so that a current flows through a circuit in which the sensor is incorporated.

  (2) Preferably, in the configuration of the above (1), the entry member may be one or more of a window glass, a door, and a shutter (corresponding to claim 2).

  As described above, windows, entrances and the like are likely to be entry points. Therefore, if breakage of the window glass, doors, and shutters constituting them can be detected at an early stage, it is effective in preventing illegal entry into the building. Therefore, according to the present configuration, the effect of suppressing illegal intrusion into the building can be further enhanced.

  (3) Preferably, in the configuration of the above (1) or (2), the intrusion port constituting member includes a lockable key portion and is arranged in the vicinity of the key portion ( Corresponding to claim 3).

  When a trespasser enters the building through a window or entrance, the vicinity of the key part of the window glass or the door is easily broken in order to unlock the key part. In this regard, according to the present configuration, the security sensor of the present invention is disposed in the vicinity of the key portion. That is, the security sensor of the present invention is arranged at a portion that is most easily destroyed when entering. For this reason, it is possible to detect the breakage of the intrusion opening component member earlier and more reliably.

  (4) Preferably, in any one of the configurations (1) to (3), the sensor body may have a configuration in which an electrical resistance increases as a temperature increases (corresponding to claim 4).

  As a result of investigation by the present inventor, the sensor body in the present invention has obtained knowledge that the electrical resistance increases as the temperature rises above a certain temperature. This is considered to be because the above-described three-dimensional conductive path P collapses due to the expansion of the elastomer at a predetermined temperature or higher, and the electrical resistance increases. As a result, for example, when the intrusion opening component member is damaged due to burning or the like accompanied by a rapid temperature change, in addition to an increase in electrical resistance due to deformation, an increase in electrical resistance due to temperature rise makes it faster and more reliable. The breakage of the entry member can be detected.

  (5) Preferably, in any one of the configurations (1) to (4), the sensor body may be configured to be elastically bendable (corresponding to claim 5). According to this configuration, it is possible to detect a change in electrical resistance when the intrusion port component is bent and deformed. In addition, it is easy to ensure a large amount of deformation in the bending deformation as compared with simple compression deformation and expansion deformation. For this reason, according to this structure, the damage by the bending deformation of the entrance member can be detected with high accuracy.

  (6) Preferably, in any one of the above configurations (2) to (5), the entry member is a window glass, and the window glass includes a glass plate and at least a part of the glass plate. The sensor body has a fixed surface fixed to the glass plate and a back surface facing away from the fixed surface. It is good to set it as the structure fixed to this glass plate by coat | covering with this glass plate from the surface side (corresponding to claim 6).

  According to this configuration, the deformation of the back surface of the sensor body is regulated by the film member. This increases the difference between the deformation amount of the fixed surface and the deformation amount of the back surface. As a result, the deformation amount of the entire sensor main body is increased, and the increase amount of electric resistance is also increased. Therefore, according to this structure, it becomes easier to detect the breakage of the entry member. Moreover, when a film member has a weather resistance and is arrange | positioned on the outdoor side of a sensor main body, degradation of a sensor main body can be suppressed.

  Moreover, what is called a crime prevention film for reinforcing the glass plate itself for the purpose of crime prevention is known. For example, when a crime prevention film is used as the film member, the strength of the glass plate itself is also improved, so that the crime prevention effect is further enhanced. In addition, since the security sensor of the present invention can be fixed to the glass plate when the security film is attached to the glass plate, the installation is easy. In this configuration, “fixed to the glass plate” means both an aspect in which the sensor body is directly fixed to the glass plate and an aspect in which the sensor body is indirectly fixed through some fixing member. including.

  (7) Preferably, in any one of the above configurations (2) to (6), the entry member is a window glass, and the window glass is formed by laminating two or more glass plates. Of the laminated glass plates, the glass plates may be arranged between adjacent glass plates (corresponding to claim 7).

  In this configuration, any of an air layer, a vacuum layer, a resin layer, and the like may be disposed between adjacent glass plates among the laminated glass plates. That is, as the window glass in this configuration, two glass plates are laminated with an air layer or a vacuum layer sandwiched therebetween, and two glass plates are laminated with a resin intermediate film sandwiched therebetween. Examples thereof include laminated glass and multilayer laminated glass obtained by combining these. According to this structure, the security sensor is interposed between adjacent glass plates. That is, the security sensor is not exposed to the indoor side or the outdoor side of the window glass. For this reason, the flatness of the window glass surface can be maintained, and there is no possibility of hindering the opening and closing of the window. Moreover, since the security sensor is not exposed to the indoor side or the outdoor side of the window glass, the security sensor is less likely to malfunction due to contact with or deformation of the obstacle.

  (8) Preferably, in any one of the constitutions (1) to (7), the sensor body is composed of an elastomer composition containing the elastomer and the conductive filler as essential components, In the percolation curve representing the relationship between the blending amount of the conductive filler and the electrical resistance, the blending amount (saturated volume fraction: φs) of the conductive filler at the second inflection point where the electrical resistance change is saturated is 35 vol% or more. It is good to have a configuration (corresponding to claim 8).

  Generally, when an electrically conductive filler is mixed with an insulating elastomer to form an elastomer composition, the electrical resistance of the elastomer composition varies depending on the blending amount of the conductive filler. In FIG. 3, the relationship between the compounding quantity of an electroconductive filler and an electrical resistance in an elastomer composition is shown typically.

  As shown in FIG. 3, when the conductive filler 102 is mixed with the elastomer 101, the electrical resistance of the elastomer composition is almost the same as the electrical resistance of the elastomer 101 at first. However, when the blending amount of the conductive filler 102 reaches a certain volume fraction, the electric resistance rapidly decreases and an insulator-conductor transition occurs (first inflection point). A blending amount of the conductive filler 102 at the first inflection point is referred to as a critical volume fraction (φc). Further, when the conductive filler 102 is further mixed, from a certain volume fraction, the change in electrical resistance is reduced and the change in electrical resistance is saturated (second inflection point). The blending amount of the conductive filler 102 at the second inflection point is referred to as a saturated volume fraction (φs). Such a change in electrical resistance is called a percolation curve and is considered to be due to the formation of a conductive path P1 by the conductive filler 102 in the elastomer 101.

  For example, if the conductive filler aggregates and forms an aggregate due to the small particle size of the conductive filler or poor compatibility between the conductive filler and the elastomer, one-dimensional conductive A path is easily formed. In such a case, the critical volume fraction (φc) of the elastomer composition is relatively small, such as about 20 vol%. Similarly, the saturated volume fraction (φs) is also relatively small. In other words, when the critical volume fraction (φc) and the saturated volume fraction (φs) are small, the conductive filler hardly exists as primary particles, and secondary particles (aggregates) are easily formed. Therefore, in this case, it is difficult to blend a large amount of the conductive filler in the elastomer. That is, it is difficult to mix the conductive filler in a state close to closest packing. Further, when a large amount of a conductive filler having a small particle diameter is blended, the aggregated structure grows three-dimensionally, so that the change in conductivity with respect to deformation becomes poor.

  According to this configuration, the sensor body is made of an elastomer composition having a saturated volume fraction (φs) of 35 vol% or more. Since the saturated volume fraction (φs) is as large as 35 vol% or more, the conductive filler is stably present in a substantially single particle state in the elastomer. Therefore, the conductive filler can be blended in a state close to closest packing.

  (9) Preferably, in any one of the constitutions (1) to (8), the filling rate of the conductive filler is 30 vol% or more and 65 vol% or less when the entire volume of the sensor body is 100 vol%. It is good to have a configuration (corresponding to claim 9).

  According to this configuration, the conductive filler is blended in the elastomer in a state close to closest packing. Therefore, a three-dimensional conductive path by the conductive filler is easily formed in the sensor body.

  (10) Preferably, in any one of the configurations (1) to (9), the conductive filler may be a carbon bead (corresponding to claim 10).

  Carbon beads have good conductivity and are relatively inexpensive. Moreover, since it has a substantially spherical shape, it can be blended at a high filling rate.

  (11) Preferably, in any one of the constitutions (1) to (10), the conductive filler may have an average particle diameter of 0.05 μm or more and 100 μm or less (corresponding to claim 11). .

  According to this configuration, the conductive filler hardly aggregates and tends to exist in a primary particle state. In addition, an average particle diameter means the average particle diameter of the electroconductive filler which exists in the state of a primary particle.

  (12) Preferably, in any one of the constitutions (1) to (11), the elastomer is silicone rubber, ethylene-propylene copolymer rubber, natural rubber, styrene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer. It is good to set it as the structure containing 1 or more types chosen from rubber | gum and acrylic rubber (corresponding to claim 12).

  According to this configuration, the compatibility between the elastomer and the conductive filler is good. For this reason, it becomes easy for a conductive filler to exist in the state of a primary particle.

  Hereinafter, embodiments of the security sensor of the present invention will be described. First, an embodiment of the security sensor of the present invention will be described, and then a sensor main body constituting the security sensor of the present invention will be described in detail.

<Security sensor>
In the embodiment described below, the security sensor of the present invention is incorporated into a security system for a building window.

(1) 1st embodiment First, arrangement | positioning of the security system incorporating the security sensor of this embodiment is demonstrated. In FIG. 4, the front view of the window where the security sensor of this embodiment is arrange | positioned is shown. In FIG. 4, the front side of the paper is the indoor side of the building, and the back side of the paper is the outdoor side of the building. As shown in FIG. 4, the window 9 includes window glasses 90 </ b> L and 90 </ b> R, window frames 91 </ b> L and 91 </ b> R, a rail frame portion 92, and a key portion 93.

  The rail frame portion 92 is disposed on the periphery of the rectangular opening of the window 9 so as to face each other in the vertical and horizontal directions. The window frames 91L and 91R each have a rectangular shape. The window frames 91L and 91R are respectively disposed inside the rail frame portion 92 so that the opening is divided into right and left. The window frames 91 </ b> L and 91 </ b> R are arranged so as to be moved in the left-right direction along the rail frame portion 92. Window glasses 90L and 90R are fitted into the window frames 91L and 91R, respectively. Each of the window glasses 90L and 90R is made of a single glass plate (float glass) and has a rectangular shape. When the window 9 is opened and closed, the window glass 90L moves outside the window glass 90R.

  The key part 93 includes a movable part 930 and a receiving part (not shown). The movable portion 930 is attached to the side surface of the left edge of the window frame 91R via the attachment portion 931 so as to be swingable in the indoor / outdoor direction. The receiving part (not shown) is attached to the indoor side right edge of the window frame 91 </ b> L so as to engage with the movable part 930. The window 9 is locked by the engagement between the movable portion 930 and the receiving portion (not shown).

  The security system 1 includes a security sensor 2, a control device 3, and an alarm device 4. The security sensor 2 is extended in the up-down direction along the indoor side right edge of the window glass 90L. The control device 3 and the alarm device 4 are both arranged above the left edge on the indoor side of the window frame 91L. The control device 3 and the alarm device 4 are formed as a single component in appearance. The security sensor 2 and the control device 3 are connected by a conducting wire 50 routed along the indoor side upper edge of the window frame 91L.

  Next, the configuration of the security sensor 2 will be described. FIG. 5 shows a perspective view near the security sensor 2. For convenience of explanation, a state in which the conductive wire 50 is omitted and the adhesive film 51 is half peeled is shown. As shown in FIGS. 4 and 5, the security sensor 2 includes a sensor body 20 and electrodes 21A and 21B. The sensor body 20 has a long plate shape extending in the vertical direction. The sensor body 20 and the electrodes 21A and 21B are covered with an adhesive film 51. The adhesive film 51 is made of polyimide. An adhesive is applied to one surface of the adhesive film 51 (the surface on the window glass 90L side). As shown by the white arrow in FIG. 5, the sensor main body 20 is fixed to the indoor side surface of the window glass 90 </ b> L by attaching the adhesive film 51 to the window glass 90 </ b> L.

  The sensor body 20 is an elastomer composite material in which carbon beads (“Nika Beads (registered trademark) ICB0520” manufactured by Nippon Carbon Co., Ltd., average particle diameter of about 5 μm) are blended in EPDM (ethylene-propylene-diene terpolymer). Consists of. The filling rate of the carbon beads is 48 vol% when the volume of the sensor body 20 is 100 vol%. In the percolation curve of the elastomer composition in which carbon beads are mixed with EPDM, the critical volume fraction (φc) is 43 vol%, and the saturated volume fraction (φs) is 48 vol%.

  An electrode 21A is attached to the upper end of the sensor body 20, and an electrode 21B is attached to the lower end. More specifically, each of the electrodes 21A and 21B is made of metal and has a strip shape extending left and right. The electrodes 21A and 21B are interposed between the sensor body 20 and the window glass 90L, and between the adhesive film 51 and the window glass 90L. The electrodes 21 </ b> A and 21 </ b> B and the control device 3 are each connected by a conductive wire 50. Similarly to the sensor body 20, the conducting wire 50 is covered with an adhesive film 51 and fixed to the window glass 90L and the window frame 91L.

  Next, the electrical configuration of the crime prevention system 1 of the present embodiment will be described. In FIG. 6, the block diagram of the crime prevention system of this embodiment is shown. As shown in FIG. 6, the crime prevention system 1 of the present embodiment includes a crime prevention sensor 2, a control device 3, and an alarm device 4. Here, the control device 3 includes a bridge circuit 30, an amplifier circuit 31, an input circuit 32, a calculation unit 33, a storage unit 34, and an output circuit 35.

  In the bridge circuit 30, resistors R1 to R3 are arranged. A Wheatstone bridge circuit is configured by the resistors R1 to R3 and the resistor R of the sensor body 20. The voltage of the power source Vin (specifically, the internal power source of the control device 3) and the electric resistance values of the resistors R1 to R3 are each known. Therefore, the resistance R of the sensor body 20 can be substantially measured by measuring the potential difference between the intermediate potential V1 between the resistor R2 and the resistor R3 and the intermediate potential V2 between the resistor R and the resistor R1. .

  Intermediate potentials V1 and V2 are input to the amplifier circuit 31. The potential difference ΔV between the intermediate potentials V1 and V2 is amplified by the amplifier circuit 31 and input to the input circuit 32 as analog voltage data. The input circuit 32 converts input analog voltage data into digital data. The storage unit 34 stores an alarm activation program in advance. In addition, an alarm activation voltage threshold th1 is stored. The computing unit 33 compares the alarm activation voltage threshold th1 with the digital data input from the input circuit 32. The output circuit 35 is connected to the alarm device 4. The output circuit 35 includes a switching element (not shown). The output circuit 35 operates the alarm device 4 and sounds an alarm.

  Next, the movement of the crime prevention system 1 of this embodiment will be described. First, the normal time of the window 9 will be described. In normal times, the sensor body 20 is in a natural state with no load. Here, as shown in FIG. 1, the conductive filler 102 is filled in a state close to closest packing. For this reason, many conductive paths P are formed in normal times. Therefore, the electrical resistance value of the sensor body 20 is the minimum value.

  As shown in FIG. 6, the potential difference ΔV between the intermediate potentials V 1 and V 2 is amplified by the amplifier circuit 31 and is always transmitted to the input circuit 32. Then, after being digitally converted by the input circuit 32, it is input to the calculation unit 33. On the other hand, the storage unit 34 stores the alarm activation voltage threshold th1 as described above. The computing unit 33 compares the potential difference (specifically, the potential difference after amplification and digital conversion, hereinafter the same in the present embodiment) ΔV and the alarm activation voltage threshold th1. In normal times, the potential difference ΔV <alarm operating voltage threshold th1 is set.

  Next, the time when the window glass 90L is broken will be described. For example, when an illegal intruder breaks the window glass 90L near the key portion 93 with a hammer or the like, the sensor body 20 is curved and deformed so as to be recessed indoors as the window glass 90L is broken. When the sensor body 20 is bent and deformed, the electric resistance value of the resistor R increases accordingly. More specifically, when the window glass 90L is broken, the conductive fillers 102 repel each other as shown in FIG. For this reason, the conductive path P collapses. Therefore, the electric resistance value of the resistor R is larger than that in normal times.

  In addition, as shown in FIGS. 4 and 5, the adhesive film 51 is fixed to the surface (backward surface) facing the fixing surface of the sensor main body 20 with the window glass 90 </ b> L. For this reason, the expansion deformation near the back surface of the sensor main body 20 due to the deformation is restrained by the adhesive film 51. Specifically, the adhesive film 51 restricts extension deformation near the back surface of the sensor main body 20, and the sensor main body 20 undergoes shear deformation. Therefore, the deformation amount of the sensor body 20 with respect to the normal time is further increased. Thus, since both surfaces of the sensor body 20 are constrained, a large strain concentration is induced, and the electric resistance value of the resistor R is further increased.

  When the electric resistance value of the resistor R increases, the amount of voltage drop of the power source Vin when passing through the resistor R correspondingly increases. Therefore, the intermediate potential V2 is lower than that in the normal state. When the intermediate potential V2 becomes low and the potential difference ΔV ≧ the alarm activation voltage threshold th1, the switching element of the output circuit 35 is turned on. Thereby, the alarm of the alarm device 4 sounds.

  Next, the effect of the security sensor 2 of this embodiment is demonstrated. As shown in FIG. 1, the security sensor 2 is disposed on the window glass 90L. For this reason, breakage of the window glass 90L can be detected. That is, it is possible to detect illegal intrusions from the most frequent windows 9 in the intrusion route. Moreover, the security sensor 2 is arrange | positioned in the key part 93 vicinity of the window glass 90L. Therefore, it is possible to reliably detect breakage in the vicinity of the key portion 93 that is likely to be broken first. Thereby, illegal intrusion from the window 9 can be detected early and reliably.

  Further, when the temperature of the sensor body 20 is about 80 ° C. or higher, the electrical resistance increases as the temperature rises. Therefore, for example, when the window glass 90L is burned by a burner or the like, in addition to an increase in electrical resistance due to deformation, the electrical resistance increases due to a rapid temperature rise, so that the window glass 90L can be more quickly and reliably installed. Damage can be detected.

  In the present embodiment, the sensor main body 20 has a long plate shape extending in the vertical direction. For this reason, not only the vicinity of the key part 93 of the window glass 90L but also the damage in a wide range extending in the vertical direction can be detected. Since the sensor body 20 is thin, it does not interfere with the window frame 91R and the window glass 90R when the window 9 is opened and closed.

  The security sensor 2 is fixed to the window glass 90 </ b> L by an adhesive film 51. In this way, the security sensor 2 can be installed by a simple operation of sticking to the existing window glass 90L. Here, since the adhesive film 51 has a thin film shape, it does not interfere with the window frame 91R and the window glass 90R when the window 9 is opened and closed. Similarly, the lead wire 50 connecting the security sensor 2 and the control device 3 is also fixed by an adhesive film 51. For this reason, the conducting wire 50 can be easily fixed. In addition, problems such as loosening of the conducting wire 50 are less likely to occur, and the detection accuracy is high. Further, when the window 9 is opened and closed, it does not interfere with the window frame 91R and the window glass 90R. Furthermore, the control device 3 and the alarm device 4 are disposed above the left edge of the window frame 91L. Here, the window frames 91L and 91R are arranged so that the left edge of the window frame 91R does not overlap the left edge of the window frame 91L when the window 9 is opened. Therefore, the control device 3 and the alarm device 4 do not get in the way when the window 9 is opened.

  In the present embodiment, the presence or absence of breakage of the window glass 90L is determined based on the potential difference ΔV itself. For this reason, compared with the case where it discriminate | determines after once converting a potential difference into an electrical resistance, time until alarm device 4 act | operates from a failure | damage may be short. Moreover, when the crime prevention system 1 is operated, a current flows through the crime prevention sensor 2 and is always energized. Thereby, an operation diagnosis can be easily performed.

  Also, there are fewer misjudgments compared to the case where damage is detected based on acceleration. That is, the acceleration is generated even by a vibration caused by wind or a small vibration such as a collision with a pet. On the other hand, the security sensor 2 of the present embodiment can reliably detect the deformation of the window glass 90L that inevitably occurs in response to an event of breakage. For this reason, there are few misjudgments compared with the case where damage is detected based on acceleration. Further, since there are few misclassifications, there is little need to dare to complicate the circuit in order to suppress misclassification.

(2) Second embodiment A difference between the present embodiment and the first embodiment is that a security sensor is arranged on a window glass having a security film attached thereto. Therefore, only the differences will be described here.

  FIG. 7 shows a perspective view near the security sensor 2. For convenience of explanation, a state in which the lead wire 50 is omitted and the security film 941L is partially peeled off is shown. Moreover, about the site | part corresponding to FIG. 5, it shows with the same code | symbol. As shown in FIG. 7, the security sensor 2 is arranged on the window glass 94L. The window glass 94L includes a glass plate 940L and a security film 941L. The security film 941L is attached so as to cover the entire indoor surface of the glass plate 940L. The security sensor 2 is interposed between the glass plate 940L and the security film 941L. That is, the sensor main body 20 and the electrodes 21A and 21B are fixed to the indoor surface of the glass plate 940L by being covered with the glass plate 940L by the security film 941L. Here, the contact surface of the sensor body 20 with the glass plate 940L corresponds to the fixed surface of the present invention. The contact surface of the sensor body 20 with the security film 941L corresponds to the back surface of the present invention.

  The security sensor of the present embodiment has the same effects as the security sensor of the first embodiment with respect to the parts having the same configuration. Moreover, according to the security sensor 2 of this embodiment, when the security film 941L is stuck on the glass plate 940L, the security sensor 2 can be fixed to the glass plate 940L. For this reason, the security sensor 2 can be easily installed. Moreover, the intensity | strength of glass plate 940L itself is also improving by sticking the crime prevention film 941L. Therefore, the crime prevention effect is higher. Furthermore, since the security film 941L covers the entire surface of the glass plate 940L, it looks better than fixing the security sensor 2 with a separate adhesive film.

(3) Third embodiment The difference between this embodiment and the first embodiment is that laminated glass is used as the window glass. Therefore, only the differences will be described here.

  FIG. 8 is a perspective view near the security sensor 2. For convenience of explanation, the conductive wire 50 is omitted, and the second glass plate 951L and the intermediate film 952L are partially removed. Moreover, about the site | part corresponding to FIG. 5, it shows with the same code | symbol. As shown in FIG. 8, the security sensor 2 is disposed on the window glass 95L. The window glass 95L includes a first glass plate 950L, a second glass plate 951L, and an intermediate film 952L. The first glass plate 950L and the second glass plate 951L are arranged to face each other in the indoor / outdoor direction. That is, the first glass plate 950L is disposed on the outdoor side, and the second glass plate 951L is disposed on the indoor side. An intermediate film 952L is interposed between the first glass plate 950L and the second glass plate 951L. The intermediate film 952L is made of polyvinyl butyral (PVB), and is thermocompression bonded between the first glass plate 950L and the second glass plate 951L.

  The security sensor 2 is interposed between the first glass plate 950L and the intermediate film 952L. That is, the sensor body 20 and the electrodes 21A and 21B are fixed to the indoor side surface of the first glass plate 950L so as to be covered with the first glass plate 950L by the intermediate film 952L. Here, the contact surface of the sensor body 20 with the first glass plate 950L corresponds to the fixed surface of the present invention. The contact surface of the sensor body 20 with the intermediate film 952L corresponds to the back surface of the present invention.

  The security sensor of the present embodiment has the same effects as the security sensor of the first embodiment with respect to the parts having the same configuration. Further, according to the security sensor 2 of the present embodiment, when the window glass 95L is manufactured, specifically, when the first glass plate 950L and the second glass plate 951L and the intermediate film 952L are thermocompression bonded, At the same time, the security sensor 2 can be fixed to the first glass plate 950L. For this reason, the security sensor 2 can be easily installed. Moreover, since the window glass 95L is a laminated glass, it is hard to be damaged. Therefore, the crime prevention effect is higher.

  The security sensor 2 is interposed between the first glass plate 950L and the intermediate film 952L. That is, it is not exposed to the indoor side or the outdoor side of the window glass 95L. For this reason, the flatness of the surface of the window glass 95L is not impaired. Therefore, there is no possibility of obstructing the opening and closing of the window 9 (see FIG. 4 above). Moreover, since the security sensor 2 is protected by the first glass plate 950L, the second glass plate 951L, and the intermediate film 952L, it is difficult to be damaged by external contact or the like. Moreover, since the security sensor 2 does not contact an obstacle directly, there is little possibility of malfunctioning. Furthermore, since the security sensor 2 is incorporated in the inside of the window glass 95L, it looks good.

(4) Fourth Embodiment A difference between the present embodiment and the first embodiment is that a multilayer glass is used as the window glass. Therefore, only the differences will be described here.

  FIG. 9 shows a perspective view near the security sensor 2. For convenience of explanation, a state in which the conductive wire 50 is omitted and the second glass plate 961L is partially removed is shown. Moreover, about the site | part corresponding to FIG. 5, it shows with the same code | symbol. As shown in FIG. 9, the security sensor 2 is arranged on the window glass 96L. The window glass 96L includes a first glass plate 960L and a second glass plate 961L. The first glass plate 960L and the second glass plate 961L are arranged facing the indoor / outdoor direction. That is, the first glass plate 960L is disposed on the outdoor side, and the second glass plate 961L is disposed on the indoor side. An air layer 962L is defined between the first glass plate 960L and the second glass plate 961L.

  The security sensor 2 is fixed to the indoor surface of the first glass plate 960L with an adhesive film 51. Specifically, the sensor main body 20 and the electrodes 21A and 21B are fixed to the indoor side surface of the first glass plate 960L by being covered with the adhesive film 51 together with a part of the first glass plate 960L.

  The security sensor of the present embodiment has the same effects as the security sensor of the first embodiment with respect to the parts having the same configuration. Moreover, according to the security sensor 2 of the present embodiment, the security sensor 2 is interposed between the first glass plate 960L and the second glass plate 961L. That is, it is not exposed to the indoor side or the outdoor side of the window glass 96L. For this reason, the flatness of the surface of the window glass 96L is not impaired. Therefore, there is no possibility of obstructing the opening and closing of the window 9 (see FIG. 4 above). Moreover, since the security sensor 2 is protected by the first glass plate 960L and the second glass plate 961L, it is difficult to be damaged by external contact or the like. Moreover, since the security sensor 2 does not contact an obstacle directly, there is little possibility of malfunctioning. Furthermore, since the security sensor 2 is incorporated in the window glass 96L, it looks good.

(5) Others The embodiment of the security sensor of the present invention has been described above. However, the embodiment is not particularly limited to the above embodiment. Various modifications and improvements that can be made by those skilled in the art are also possible.

  For example, in the above embodiments, the security sensor of the present invention is arranged on the window glass. However, the arrangement location is not limited to the window glass. For example, when arrange | positioning to a window, the sealing member arrange | positioned in the clearance gap between a window glass and a window frame, a window shutter, a shutter, etc. may be sufficient. Other than windows, doors such as entrances, doorways, etc., shutters such as stores and garages, gates, etc. may be used. If it arrange | positions in these multiple places, a crime prevention effect can be heightened more. Further, a plurality of security sensors of the present invention may be arranged in one intrusion member. For example, in the case of the window glass shown in the above embodiment, security sensors may be arranged on two to four sides of the window glass along the window frame. In this way, damage can be detected over a wider range.

  The kind of window glass, thickness, etc. which arrange | position the security sensor of this invention are not specifically limited. In addition to the float glass, laminated glass, and multi-layer glass shown in the above-described embodiment, template glass, tempered glass, netted glass, multi-layer laminated glass, and the like may be used. Further, the materials of the adhesive film and the security film are not particularly limited.

  In the said embodiment, the sensor main body was directly fixed to the surface of the window glass with the adhesive film. However, when a security film or the like is attached to the window glass, the sensor body may be indirectly fixed thereon. Further, the sensor body may be fixed via a fixing member such as a base film depending on the material of the entry member.

  The configuration of the sensor body is not limited to the above embodiment. This will be described later. Further, the shape of the sensor body is not particularly limited. In addition to the long plate shape of the above embodiment, it may be a square plate shape, a disk shape, or the like. Further, the number of electrodes connected to the sensor body is not particularly limited. For example, in the case of a long sensor body as in the present embodiment, if electrodes are arranged at predetermined intervals in the longitudinal direction, damage can be detected at intervals between adjacent electrodes, so that the location of the damage can be specified. It becomes possible. When the electrode is fixed to the sensor body by vulcanization adhesion, the electrode can be disposed simultaneously with the vulcanization molding of the sensor body.

  The arrangement of the control device and the alarm device connected to the security sensor of the present invention is not particularly limited. In the said embodiment, although these were connected with the conducting wire, you may transmit the voltage data from a sensor main body, etc. to a control apparatus wirelessly. In this case, since wiring is not required, the degree of freedom of arrangement of the control device and the like is increased. Moreover, in the said embodiment, although voltage data was output from the security sensor, you may output electrical resistance data. Also, the type of alarm device is not particularly limited. In addition to sounding an alarm, notification to a security company or a mobile phone may be performed. Further, instead of the alarm device, a patrol lamp or the like installed outdoors may be connected to the control device.

  Further, the method for determining the breakage of the entry member is not particularly limited. For example, when the sensor main body is affixed to the window glass, the sensor main body falls off together with the broken pieces due to breakage of the window glass. At this time, since the debris remains attached to the sensor body, the shape and weight of the debris are restricted, and the sensor body may not be completely restored to the original state (no load state). By paying attention to this point, it may be determined whether or not the window glass is broken on the basis of whether or not the electrical resistance value of the security sensor returns to the original state after a certain time has elapsed.

  In this respect, in the case of the acceleration sensor, even if the window glass is bent or broken by the wind, the acceleration returns to zero if there is no impact. For this reason, it is difficult to determine whether the window glass is really broken or simply bent. On the other hand, according to the above-described determination method, even if the electrical resistance value once increases, it can be determined that the window glass is simply bent if it quickly returns to the original state. Moreover, if the electrical resistance value does not return to the original state, it can be determined that the window glass is broken. That is, it is possible to clearly distinguish between breakage and non-breakage.

<Sensor body>
The sensor body constituting the security sensor of the present invention has an elastomer and a conductive filler. The elastomer can be appropriately selected from rubber and thermoplastic elastomer. The elastomer is desirably insulative. In addition, when a mixture (elastomer composition) with a conductive filler is prepared, it is desirable to use one having a saturated volume fraction (φs) in a percolation curve of 35 vol% or more. This is because when the saturated volume fraction (φs) is less than 35 vol%, it is difficult to blend the conductive filler in a substantially single particle state with a high filling rate. Further, in the region of the saturated volume fraction (φs) or more, the electric resistance is low and stable conductivity is expressed. Therefore, when the saturated volume fraction (φs) is 35 vol% or more, the range of change in electrical resistance from the conductor to the insulator when deformed is widened. Further, it is more preferable to use a saturated volume fraction (φs) of 40 vol% or more. In addition, the “elastomer composition” in the present specification includes an elastomer and a spherical conductive filler as essential components. That is, a mixture of an elastomer and a spherical conductive filler may be used, or a mixture of an elastomer, a spherical conductive filler, and other additives may be used.

In consideration of the affinity with the conductive filler, an elastomer having a gel fraction represented by the following formula (1) of 15% or less may be used. The gel fraction is more preferably 10% or less.
Gel fraction (%) = (Wg−Wf) / Wf × 100 (1)
[Wg in formula (1) is a solvent-insoluble content (gel content of conductive filler and elastomer) obtained when an elastomer composition obtained by mixing a conductive filler in an elastomer is dissolved in a good solvent for the elastomer. It is weight. Wf is the weight of the conductive filler. In addition, as a good solvent of an elastomer, the thing with the close SP value (solubility parameter) of a solvent and an elastomer is desirable, For example, toluene, tetrahydrofuran, chloroform, etc. are mentioned. ]

  The value of the gel fraction is an indicator of the critical volume fraction (φc) in the percolation curve. That is, when the critical volume fraction (φc) is less than 30 vol%, the gel fraction becomes a relatively large value because a large amount of elastomer adsorbed and bonded to the aggregate of the conductive filler exists. On the other hand, when the critical volume fraction (φc) is 30 vol% or more, the conductive filler exists in a substantially single particle state, so that the amount of elastomer adsorbed and bonded to the aggregate of the conductive filler is small, and the gel The fraction is a relatively small value of 15% or less.

  Specific examples of elastomers include, for example, natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), acrylonitrile-butadiene copolymer rubber (NBR), styrene-butadiene copolymer rubber (SBR), Ethylene-propylene copolymer rubber [ethylene-propylene copolymer (EPM), ethylene-propylene-diene terpolymer (EPDM), etc.], butyl rubber (IIR), halogenated butyl rubber (Cl-IIR, Br-IIR, etc.) ), Hydrogenated nitrile rubber (H-NBR), chloroprene rubber (CR), acrylic rubber (AR), chlorosulfonated polyethylene rubber (CSM), hydrin rubber, silicone rubber, fluorine rubber, urethane rubber, synthetic latex and the like. . Examples of the thermoplastic elastomer include various thermoplastic elastomers such as styrene, olefin, urethane, polyester, polyamide, and fluorine, and derivatives thereof. Of these, one kind may be used alone, or two or more kinds may be used in combination. Of these, EPDM having extremely good compatibility with the conductive filler is preferable. Also suitable are NBR and silicone rubber, which have good compatibility with the conductive filler.

  The conductive filler has a spherical shape. The spherical shape includes not only a true sphere and a substantially true sphere, but also an oval sphere, an oval sphere (a shape in which a pair of opposing hemispheres are connected by a cylinder), a partial sphere, a sphere having a different radius for each portion, a water droplet shape, and the like. included. For example, the aspect ratio of the conductive filler (the ratio of the long side to the short side) is preferably in the range of 1 or more and 2 or less. This is because when the aspect ratio is larger than 2, a one-dimensional conductive path is easily formed by contact between the conductive fillers. In this case, the saturated volume fraction (φs) may be less than 35 vol%. Further, from the viewpoint of bringing the filling state of the conductive filler in the elastomer closer to the closest packing state, it is preferable to employ particles having a true sphere or a shape very close to a true sphere (substantially spherical) as the conductive filler.

  The conductive filler is not particularly limited as long as it is conductive particles. Examples thereof include fine particles such as carbon materials and metals. Of these, one can be used alone, or two or more can be used in combination.

  It is desirable that the conductive filler is not aggregated as much as possible and exists in the form of primary particles. Therefore, when selecting the conductive filler, it is preferable to consider the average particle diameter, compatibility with the elastomer, and the like. For example, the average particle diameter (primary particles) of the conductive filler is desirably 0.05 μm or more and 100 μm or less. If it is less than 0.05 μm, it tends to aggregate and form secondary particles. Moreover, there exists a possibility that the said saturated volume fraction ((phi) s) may be less than 35 vol%. Preferably it is 0.5 micrometer or more, More preferably, it is 1 micrometer or more. On the other hand, when the thickness exceeds 100 μm, the translational motion (parallel motion) of the conductive filler due to elastic deformation becomes relatively smaller than the particle diameter, and the change in electric resistance against the elastic deformation of the sensor body becomes slow. Preferably it is 60 micrometers or less, More preferably, it is 30 micrometers or less. In addition, the critical volume fraction (φc) and the saturated volume fraction (φs) are within the desired ranges by appropriately adjusting the combination of the conductive filler and the elastomer, the average particle diameter of the conductive filler, and the like. Can be adjusted.

  Moreover, as for the value of D90 / D10 in the particle size distribution of an electroconductive filler, it is desirable that it is 1-30. Here, D90 is the particle diameter at which the cumulative weight is 90% in the cumulative particle size curve, and D10 is the particle diameter at which the cumulative weight is 10%. When the value of D90 / D10 exceeds 30, since the particle size distribution becomes broad, the increase behavior of the electric resistance with respect to the deformation amount of the sensor body becomes unstable. Thereby, the reproducibility of detection may be reduced. It is more preferable that the value of D90 / D10 is 10 or less. In addition, when using 2 or more types of particle | grains as an electroconductive filler, the value of D90 / D10 should just be 100 or less.

  As such a conductive filler, for example, carbon beads are suitable. Specifically, Osaka Gas Chemical Co., Ltd. mesocarbon micro beads [MCMB6-28 (average particle size of about 6 μm), MCMB10-28 (average particle size of about 10 μm), MCMB25-28 (average particle size of about 25 μm)], Carbon micro beads manufactured by Nippon Carbon Co., Ltd .: Nika beads (registered trademark) ICB, Nika beads PC, Nika beads MC, Nika beads MSB [ICB 0320 (average particle size of about 3 μm), ICB 0520 (average particle size of about 5 μm), ICB 1020 (average particle size of about 10 μm) ), PC0720 (average particle diameter of about 7 μm), MC0520 (average particle diameter of about 5 μm)], Nisshinbo carbon beads (average particle diameter of about 10 μm), and the like.

  The conductive filler is blended in the elastomer at a high filling rate. In order to develop desired conductivity, the conductive filler is desirably blended at a ratio equal to or higher than the critical volume fraction (φc) in the percolation curve. From the viewpoint of blending the conductive filler in a substantially single particle state with a high filling rate, the critical volume fraction (φc) is desirably 30 vol% or more. It is more preferable that it is 35 vol% or more. Therefore, for example, the filling rate of the conductive filler is desirably 30 vol% or more and 65 vol% or less when the entire volume of the sensor body is 100 vol%. In the case of less than 30 vol%, the conductive filler is not blended in a state close to the closest packing, and thus desired conductivity is not exhibited. In addition, the change in the electric resistance with respect to the elastic deformation of the sensor body becomes slow, and it becomes difficult to control the increase behavior of the electric resistance. It is more preferable that it is 35 vol% or more. On the other hand, when it exceeds 65 vol%, mixing with the elastomer becomes difficult, and the molding processability is lowered. In addition, the sensor body is difficult to elastically deform. It is more preferable that it is 55 vol% or less.

  In addition to the elastomer and the conductive filler, various additives may be blended in the sensor body. Examples of the additive include a crosslinking agent, a vulcanization accelerator, a vulcanization aid, an antiaging agent, a plasticizer, a softening agent, and a colorant. In addition to the spherical conductive filler, a conductive filler having an irregular shape (for example, a needle shape) may be blended.

  The sensor body can be manufactured, for example, as follows. First, additives such as a vulcanization aid and a softening agent are added to the elastomer and kneaded. Subsequently, after adding a conductive filler and kneading, a crosslinking agent and a vulcanization accelerator are further added and kneaded to obtain an elastomer composition. Next, the elastomer composition is formed into a sheet, filled in a mold, and press vulcanized under predetermined conditions.

  Hereinafter, a glass breakage test using the security sensor of the present invention will be described.

(1) Float glass breakage test <Test method>
In this test, a sensor body produced as follows was used. First, 85 parts by weight (85 g) of oil-extended EPDM (“Esplen (registered trademark) 6101” manufactured by Sumitomo Chemical Co., Ltd.) (34 g) and 34 parts of oil-extended EPDM (“Esplen 601” manufactured by Sumitomo Chemical Co., Ltd.) 34 Part (34 g), 30 parts (30 g) of EPDM (“Esplen 505” manufactured by Sumitomo Chemical Co., Ltd.), 5 parts (5 g) of zinc oxide (manufactured by Hakusui Chemical Co., Ltd.), stearic acid (“Lunac” (registered by Kao Corporation) 1 part (1 g) of trademark S30 ") and 20 parts (20 g) of paraffinic process oil (" Samper (registered trademark) 110 "manufactured by Nippon San Oil Co., Ltd.) were kneaded with a roll kneader. Next, 270 parts (270 g) of carbon beads (“Nika Beads ICB0520” manufactured by Nippon Carbon Co., Ltd., average particle diameter of about 5 μm, D90 / D10 = 3.2 in the particle size distribution) are added and mixed in a roll kneader, Dispersed. Furthermore, as a vulcanization accelerator, zinc dimethyldithiocarbamate (“Noxeller (registered trademark) PZ-P” manufactured by Ouchi Shinsei Chemical Co., Ltd.) 1.5 parts (1.5 g), tetramethylthiuram disulfide (manufactured by Sanshin Chemical Co., Ltd.) "Sunseller (registered trademark) TT-G") 1.5 parts (1.5 g), 2-mercaptobenzothiazole ("Noxeller MP" manufactured by Ouchi Shinsei Chemical) 0.5 parts (0.5 g) And 0.56 part (0.56 g) of sulfur (“Sulfax T-10” manufactured by Tsurumi Chemical Co., Ltd.) were added, mixed and dispersed with a roll kneader to prepare an elastomer composition.

  The volume fraction of carbon beads in the prepared elastomer composition was about 48 vol% when the volume of the entire elastomer composition was 100 vol%. Further, the critical volume fraction (φc) in the percolation curve of the elastomer composition was about 43 vol%, and the saturated volume fraction (φ s) was about 48 vol%. Moreover, when the elastomer composition was dissolved in a solvent (toluene) and the solvent insoluble content was measured, the gel fraction was about 3%.

  Next, the elastomer composition was molded into a band having a predetermined size to obtain a molded body. The molded body was filled in a mold, electrodes were arranged at both ends in the longitudinal direction, and press vulcanized at 170 ° C. for 30 minutes to obtain a sensor main body. The filling rate of carbon beads in the obtained sensor main body was about 48 vol% when the volume of the sensor main body was 100 vol%.

  The prepared sensor main body was attached to one surface (interior side surface) of the float glass to constitute a security sensor, and the response of the security sensor to the impact from the other surface (outside surface) was evaluated. FIG. 10 shows a layout of security sensors. In addition, the fixing method of each security sensor was made the same as said 1st embodiment (refer above-mentioned FIG. 5). As shown by hatching in FIG. 10, the security sensors 2 are respectively arranged at five locations on the periphery of the float glass 80 (length 425 mm, width 576 mm). The security sensor 2 is fixed to the surface of the float glass 80 by an adhesive film (not shown). The security sensor 2 has a first lower part: No. 1. Second lower part: No. 5, upper part: No. 2, Left: No. 3, right part: No. 4 and so on. No. The security sensors 2 of 1 to 4 are respectively arranged away from the window frame 81 by about 20 mm. No. The security sensor 2 of No. 5 One security sensor 2 is spaced upward by about 10 mm. No. An acceleration sensor 82 is disposed above the right end of the crime prevention sensor 2.

  The security sensor 2 includes a sensor main body 20 and electrodes (not shown) disposed at both ends of the sensor main body 20. No. The sensor bodies 20 of 1 to 4 have a long plate shape with a length of 50 mm and a thickness of 0.5 mm. No. The sensor body 20 of No. 5 has a long plate shape with a length of 145 mm and a thickness of 0.5 mm. The sensor main body 20 is connected to an external circuit through electrodes and conductive wires (both not shown). When an impact is applied from the outdoor side of the float glass 80 (the rear side in the drawing) and the float glass 80 is broken, the security sensor 2 is deformed. The electrical resistance value of the security sensor 2 is output to an external circuit from an electrode (not shown) or the like. Further, the acceleration of impact is measured by the acceleration sensor 82.

  Two types of tests were conducted as follows. In the first test, the center of the outdoor surface of the float glass 80 (surface in the direction opposite to the paper surface) was hit with an impact hammer. The acceleration of the impact at this time and the change of the electrical resistance value of each security sensor 2 were measured. In addition, the float glass 80 is not damaged by the impact at this time. In the second test, the float glass 80 was broken by hitting the lower part of the outdoor surface of the float glass 80 with an impact hammer. The impact input position is No. 5 is a position (a dotted circle P in FIG. 10) spaced about 50 mm upward from the center of the security sensor 2. The acceleration of the impact at this time and the change of the electrical resistance value of each security sensor 2 were measured.

<Test results>
First, the results of the first test are shown in FIG. FIG. 11 shows changes over time in impact hammer hitting force, impact acceleration, and electrical resistance value of each security sensor in the first test. As shown in FIG. 11, the acceleration changed greatly in response to the impact of the impact hammer. On the other hand, the electrical resistance value hardly changed in any of the security sensors. From this, it is understood that the security sensor of the present invention does not respond in the case of an impact that does not damage the float glass. That is, the security sensor of the present invention is unlikely to malfunction due to small vibrations caused by wind or the like.

  Next, the results of the second test are shown in FIG. FIG. 12 shows the change over time in the acceleration of impact and the electrical resistance value of each security sensor in the second test. As shown in FIG. 12, the acceleration changes with respect to the impact of breaking the float glass. 1, no. The electrical resistance value of the crime prevention sensor No. 5 has greatly increased. On the other hand, no. The electrical resistance values of the security sensors 2 to 4 hardly changed. That is, only the security sensors (No. 1, 5) close to the breakage position of the float glass responded greatly. As described above, according to the security sensor of the present invention, it is possible to reliably detect the breakage of the entry member and to identify the breakage position.

<Heating test>
No. above. A heating test was conducted on one security sensor. That is, no. The vicinity of the security sensor 1 was heated, and the relationship between the temperature of the sensor body and the electrical resistance value was examined. The results are shown in FIG. As shown in FIG. 13, the electric resistance value increased rapidly at about 80 ° C. or higher. From this, it can be seen that the security sensor of the present invention increases in electrical resistance value due to temperature rise in addition to increase in electrical resistance value due to deformation. Thus, the security sensor of the present invention detects a breakage of the entry member and also functions as a temperature sensor.

(2) Laminated glass breakage test <Test method>
The sensor body produced in the test of (1) above is attached to one surface (interior surface) of the laminated glass to constitute a security sensor, and the response of the security sensor to the impact from the other surface (outside surface) Sex was evaluated. The arrangement of the security sensor in the laminated glass is No. in FIG. 1 and no. Two locations were used. Each security sensor was fixed with an adhesive film as in the test of (1) above. The acceleration sensor is No. 1 was placed on the right side of the security sensor.

  Three types of tests were performed with varying degrees of impact. That is, the impact strength of the impact hammer was changed, the outdoor surface of the laminated glass was hit, and the impact acceleration and the change in the electrical resistance value of each security sensor were measured. The impact input position is No. It was set as a position (dotted line circle P in FIG. 10 above) spaced about 60 mm upward from the center of one security sensor.

  FIG. 14 shows a model diagram at the time of impact input in the first test. FIG. 15 shows a model diagram at the time of impact input in the second test. FIG. 16 shows a model diagram at the time of impact input in the third test. As shown in FIGS. 14 to 16, the laminated glass 83 includes a first glass plate 830, a second glass plate 831, and an intermediate film 832. The first glass plate 830 is disposed on the outdoor side, and the second glass plate 831 is disposed on the indoor side so as to face each other. An intermediate film 832 is interposed between the first glass plate 830 and the second glass plate 831. The intermediate film 832 is made of PVB, and is thermocompression bonded between the first glass plate 830 and the second glass plate 831. The security sensor 2 is fixed to the indoor side surface of the second glass plate 831. In each test, the impact hammer 84 was used to strike the outdoor surface of the laminated glass 83, and the acceleration of the impact and the change in the electrical resistance value of each security sensor 2 were measured. In the first test, as shown in FIG. 14, the laminated glass 83 was not damaged by the impact by the impact hammer 84. In the second test, as shown in FIG. 15, only the first glass plate 830 was damaged. In the third test, as shown in FIG. 16, the laminated glass 83, that is, the first glass plate 830 and the second glass plate 831 were damaged, and the sensor body 20 was also deformed accordingly.

<Test results>
First, the results of the first test are shown in FIG. FIG. 17 shows changes over time in the acceleration of impact and the electrical resistance value of each security sensor in the first test. As shown in FIG. 17, the acceleration changed greatly with respect to the impact of the impact hammer. On the other hand, the electrical resistance value is No. 1, no. There was almost no change in any of the security sensors of 2. From this, it is understood that the security sensor of the present invention does not respond in the case of an impact that does not break the laminated glass. Therefore, the security sensor of the present invention is unlikely to malfunction due to a small vibration caused by wind or the like.

  Next, the results of the second test are shown in FIG. FIG. 18 shows changes over time in the acceleration of impact and the electrical resistance value of each security sensor in the second test. As shown in FIG. 18, the acceleration changes with respect to the impact of breaking the first glass plate. The electrical resistance value of the security sensor 1 increased slightly. On the other hand, no. The electrical resistance value of the security sensor No. 2 hardly changed.

  Next, the results of the third test are shown in FIG. FIG. 19 shows changes over time in the acceleration of impact in the third test and the electrical resistance value of each security sensor. As shown in FIG. 19, the acceleration changes with respect to the impact of breaking the laminated glass. The electrical resistance value of the security sensor No. 1 has greatly increased. On the other hand, no. The electrical resistance value of the security sensor No. 2 hardly changed. That is, only the security sensor near the broken position of the laminated glass responded greatly. As described above, according to the security sensor of the present invention, it is possible to reliably detect the breakage of the entry member and to identify the breakage position.

It is a schematic diagram which shows the electroconductive path before the load application of the sensor main body in this invention. It is a schematic diagram which shows the conductive path after the load application of the sensor main body. It is a schematic diagram of the percolation curve in an elastomer composition. It is a front view of the window where the security sensor of the first embodiment of the present invention is arranged. It is a perspective view of the security sensor vicinity. It is a block diagram of the crime prevention system of a first embodiment. It is a perspective view near the security sensor of the second embodiment of the present invention. It is a perspective view near the security sensor of a third embodiment of the present invention. It is a perspective view near the security sensor of 4th embodiment of this invention. It is an arrangement plan of a security sensor in a float glass breakage test. It is a graph which shows the time-dependent change of the impact strength of the impact hammer of the 1st test in the same test, the acceleration of an impact, and the electrical resistance value of each security sensor. It is a graph which shows the time-dependent change of the acceleration of the impact of the 2nd test in the same test, and the electrical resistance value of each security sensor. It is a graph which shows the relationship between the temperature of a sensor main body, and an electrical resistance value. It is a model figure at the time of the impact input of the 1st test in a laminated glass breakage test. It is a model figure at the time of the impact input of the 2nd test in the same test. It is a model figure at the time of the impact input of the 3rd test in the same test. It is a graph which shows the time-dependent change of the acceleration of the impact of the 1st test in the same test, and the electrical resistance value of each security sensor. It is a graph which shows the time-dependent change of the acceleration of the impact of the 2nd test in the same test, and the electrical resistance value of each security sensor. It is a graph which shows the time-dependent change of the acceleration of the impact of the 3rd test in the same test, and the electrical resistance value of each security sensor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1: Security system 2: Security sensor 20: Sensor main body 21A, 21B: Electrode 3: Control apparatus 30: Bridge circuit 31: Amplifier circuit 32: Input circuit 33: Arithmetic unit 34: Storage unit 35: Output circuit 4: Alarm device 50 : Conductor 51: Adhesive film 80: Float glass 81: Window frame 82: Acceleration sensor 83: Laminated glass 830: First glass plate 831: Second glass plate 832: Intermediate film 84: Impact hammer 9: Window 90L, 90R: Window glass 91L, 91R: Window frame 92: Rail frame part 93: Key part 94L: Window glass 940L: Glass plate 941L: Security film 95L: Window glass 950L: First glass plate 951L: Second glass plate 952L: Intermediate film 96L : Window glass 960L: First glass plate 961L: Second glass plate 962L: Air layer 100: Sensor body 01: Elastomer 102: conductive filler [Delta] V: voltage difference R1-R3: resistance V1, V2: the intermediate potential Vin: Power P: conducting path P1: conductive path

Claims (12)

An elastically deformable sensor body having an elastomer and a spherical conductive filler blended in the elastomer in a substantially single particle state and with a high filling rate, and the electrical resistance increases as the amount of deformation increases; ,
An electrode connected to the sensor body and capable of outputting the electrical resistance;
With
A security sensor that is disposed on an intrusion port constituting member that constitutes an intrusion port from the outside and is capable of detecting breakage of the intrusion port constituting member from deformation of the sensor body accompanying deformation of the intrusion port constituting member.   The security sensor according to claim 1, wherein the entry member is at least one of a window glass, a door, and a shutter. The entry port component includes a lockable key portion,
The security sensor according to claim 1, wherein the security sensor is disposed in the vicinity of the key portion.   The security sensor according to any one of claims 1 to 3, wherein the sensor body increases in electrical resistance as the temperature rises.   The security sensor according to any one of claims 1 to 4, wherein the sensor body is elastically bendable. The entry member is a window glass,
The window glass has a glass plate and a film member covering at least a part of the glass plate,
The sensor body has a fixed surface fixed to the glass plate, and a back surface facing away from the fixed surface,
The security sensor according to any one of claims 2 to 5, wherein the security member is fixed to the glass plate by covering with the glass plate from the back surface side with the film member. The entry member is a window glass,
The window glass is formed by laminating two or more glass plates,
The security sensor according to any one of claims 2 to 6, which is interposed between the adjacent glass plates among the laminated glass plates. The sensor body is composed of an elastomer composition containing the elastomer and the conductive filler as essential components,
In the percolation curve representing the relationship between the blending amount of the conductive filler and the electrical resistance of the elastomer composition, the blending amount of the conductive filler at the second inflection point at which the electrical resistance change is saturated (saturated volume fraction: φs) ) Is 35 vol% or more. The security sensor according to claim 1.   The security sensor according to any one of claims 1 to 8, wherein a filling rate of the conductive filler is 30 vol% or more and 65 vol% or less when the entire volume of the sensor main body is 100 vol%.   The security sensor according to any one of claims 1 to 9, wherein the conductive filler is carbon beads.   The security sensor according to any one of claims 1 to 10, wherein the conductive filler has an average particle size of 0.05 µm or more and 100 µm or less.   12. The elastomer according to claim 1, wherein the elastomer includes at least one selected from silicone rubber, ethylene-propylene copolymer rubber, natural rubber, styrene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber, and acrylic rubber. Security sensor as described in 4.

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