GB2300263A

GB2300263A - Piezoelectric intruder detection system

Info

Publication number: GB2300263A
Application number: GB9508730A
Authority: GB
Inventors: Josef Petr Prokopius
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-04-28
Filing date: 1995-04-28
Publication date: 1996-10-30
Anticipated expiration: 2015-04-28
Also published as: CZ124096A3; GB9508730D0; GB2300263B

Abstract

A sensor Fig. 1 for detection of an intruder in security alarm systems is constructed with piezo electric material 1 and secured to parts of protected article or object which is likely to be forced by the intruder, provides an electrical signal when slightly deflected or disturbed to a simple processing electronic circuit constructed as an independent alarm module or can be integrated into new or existing alarm systems. A plurality of sensors S1-S8 may be connected to the circuit, Fig. 2.

Description

PIEZOELECTRIC DETECTION SYSTEM FOR SECURITY DEVICES.

This invention relates to electronic security systems, in particular to intruder detection, for protecting objects such as buildings, open storage articles, bank safes, vehicles, ships against intruders and may also be used in detention centers as protection against escape.

Today's security systems are using variety of electronic detectors for detecting an intruder which are expensive, have many limitations, are prone to false triggering caused by changes of temperature and weather conditions, wind, flying inset or dust and are generally situated inside protected property therefore the systems can not be in operational mode when the protected object is occupied because they are mainly situated inside protected property detecting movement or body heat and they set off alarms when already damage is caused by forced entry.

This invention introduces a very effective and economical way of intruder detection and a simple but sophisticated and reliable security system using as a means of intruder detection piezo-electric sensors. The piezoelectric sensors are mounted to parts of entry means such as doors, windows, sealing, floors and fittings of buildings and doors,windows, bonnets, boots, sun roofs and suspension of motor vehicles, pictures and other objects in art galleries, computers, computer files, instruments and aparaturs, draws, drug stores in hospitals, fittings, loose objects etc, and in detention centers may be fitted within construction of buildings. The sensors provide electrical output signal to processing and control electronic alarm system when slightly deflected and are sensitive only to touch, force, impact or vibration.Their sensitivity is adjustable for any conditions for protected situation. They are immune to false triggering, aging, changing weather conditions, temperature, inset interference, dust and dirt. The strength of the signal is proportional to applied force and this can be used to perform beside usual alarm function some priority functions e.g. switch ON or OFF lights, alert the monitoring officers or police before setting off the main alarm sounder. Also when alarm goes off just after intruder's several tentative touches to some entry means, the psychological effect on intruder will urge him to leave the seen without causing any damage to protected object.

This way of detection enables very effective property protection and variety of modules can be constructed as a complete economical alarm system or simple independent module to integrate into existing security systems, or alternatively constructed as a simple, economical battery operated module for protecting objects and articles.

A specific embodiment of the Invention will now be described by the way of example with reference to the accompanying drawings in which: Fig. 1 shows a typical piezo-electric sensor section.

Fig. 2 shows a typical block diagram with mixed connection of the piezo sensors to the processing unit and detection of the signal strength.

Fig. 3 shows a typical simple example of the piezo sensor deposited on a metal fitting of a door.

Fig. 4 shows a typical block diagram of an independent simple module suitable for direct use or for integration into existing security systems.

Fig. 5 shows a typical block diagram of a module for integration into existing electronic security devices with two independent channels.

Fig. 6 shows a round piezo sensor inserted in a hole in a door.

Disclosure of the Invention.

An electronic security system using as a detector sensor for detecting an intruder or unauthorised persons a piezo-electric sensor (S) which may be made as a deposit of piezo-electric material (1) on a flexible backing from rigid or semirigid material such as metal or plastic (2) with at least two electrical connections (5), which do not to be polarised, to the piezo-electric material deposit from which one conductor (5a) may be direct to the piezo-electric material (1) and the second (5b) to the metal backing (2) and the piezo electric deposit (1) and the electrical connections (5a,5b) may be protected by a layer from insulating material, or piezo-electric material particles dispersed in molded, extruded or casted material such as plastic or rubber also with at least two electrical connections, this molded or casted material may have variety of shapes such as a pad, a block, a wire or a shim adopted for a particular application.

The sensor (S) is secured to some part of the protected object or property (4) such as doors, windows, floors, sealing of buildings and doors, windows, bonnets, boots, suspension of motor vehicles, or to expensive instruments, aparaturs, computer files, draws and galleries art by mechanical means such as by screws or by adhesive, adhesive tape, double sided adhesive tape (3), or piezo-electric material applied as a deposited pad directly onto the parts, construction or fittings (7),(10) of the protected property serving in this form as the said sensor and having also two electrical connections (5a and 5c) from which the one connection (5a) may be to the piezo-electric material and the second (5c) being common with the metal construction or fitting itself (7),(10).

Any of these sensors may be attached to a surface or alternatively can be directly built into some part of the protected object such as sealing, walls and floors, or inserted into space provided, such as a hole, recess or grove (12), in some part or construction of the protected property for increased security in places such as detention centres.

The said sensor provides an electrical signal when touched, slightly deflected, vibrated or in some way disturbed as instantly polluted, the signal being fed by means of conductors from the electrical connections of the sensor to a processing unit (U) which may be a part of the electronic circuit providing also other functions and provides electrical output signal on terminal (a) used further for processing the signal to initiate setting off the alarm. A plurality of these sensors (S1 to Sn) may be used and their two connection wired to the processing unit (U) in parallel, series or mixed connections regardless the polarities of the sensors to one common two point input (x,y) of the processing unit making the wiring simple, efficient and economical.Alternatively the sensors divided into groups connected in the same manner to several independent channels (CH1,CH2) with different sensitivity levels or for a particular purpose to suit to an individual protected situation is shown in Fig. 5 and with the addition of a timer (T), counter of output signals (C) with display (D), additional function processors (F1,F2) and multiway switch (SW) forming a part of security system with high level of performance. The sensors respond only to touch, force, impact vibration or instant polution making the system very immune to false triggering and their sensitivity may be controlled by a simple means such as by variable resistor (P).

This kind of piezo sensors allow the security system to be operative even when the protected property is occupied providing a high level of security. The strength of the signal is proportional to a level of deflection induced by applied force or other disturbance and may be monitored and further processed by additional electronic processor, such as an analogue to digital converter (A to D) or by voltage to frequency converter (V to F) and provide additional functions initiated by strength of the signal on output terminals (b,c,d,e,) to alert monitoring authorities such as security officers or police prior to providing output from terminal (f) and setting off the main alarm or sounder giving greater possibilities to secure the intruder. Alternatively every output signal from any sensor may be used to provide visual or audio indication before the main alarm is set off by the indicator (11) which may be remotely situated in convenient location. An very compact module suitable for integration into existing security system or as a battery operated economical independent alarm system as shown in Fig. 4 may be constructed using the sensor (S), processing unit (U) and visual or audible alarm indicator (B) for use in guarding articles in shops, arts in galleries etc. and with addition of a timer (T), counter (C) with display (D) the module will provide a complete sophisticated mini-system suitable for many applications. This very effective and economical miniature modules may be used as temporary warning devices or in places of prohibited unauthorised entry or manipulation, or secured to loose articles, in enclosures of instruments, aparaturs in laboratories, computers, cash boxes, draws, drug stores in hospitals or to goods in shops, art in galleries providing visual or audio alarm indication (B) when touched avoiding damage and theft. Any of the modules shown in Fig. 2, 4 and 5 are suitable to integrate into any existing electronic security alarm systems which use logic integrated circuits or microprocessor or microcomputers control or with addition of few parts to provide complete security alarm systems.

Claims

CLAIMS.

1. Piezo Electric Detection System for Security Devices exploiting the electro-mechanical property of piezoelectric materials, which generate electricity when subjected to deflection, in a form of at least one sensor, where such sensor consists of at least one component from piezoelectric material consisting of at least one kind of piezoelectric material and at least one component of a foundation made from at least one kind of a base material, the base material providing the foundation for construction of at least one such sensor and where the piezoelectric material is the source of the electrical outputs, taken by at least two electrical conductors from the piezoelectric material of such sensor as the output signals from the sensor for processing, and where at least one of such sensors is situated in the location of a protected object so as to serve as a means of intruder detection and were the activity of the intruder in the protected location causes a physical disturbance to the protected object, so to the sensor inducing a microscopic ?deflection of the sensor so that the output signal from the sensor is produced, and the output signal fed to at least one means of signal processing, the processing unit, the processing unit performing the function of conditioning the output signal to be used for performing at least one from functions for providing at least one of the of information related to the security of the protected object by such a security device.

2. Piezo electric detection system for security devices as claimed in Claims 1 characterised by construction of 'such sensor in a form of piezo electric material (1) deposited in at least one layer of at least one thickness (1), of least one size, at least one shape in at least one area of the foundation (2).

3. Piezo electric detection system for security devices as claimed In Claims 1 characterised by construction of such sensor in a form of piezo electric material particles dispersed to at least one concentration in at least one discrete volume in at least one section of the foundation (12).

4. Piezo electric detection system for security devices as claimed in preceding Claim 1, and Claim 2 and Claim 3 characterised in the construction of the sensor, where the piezoelectric material is applied directly to at least one part of the protected object which is providing the foundation of such sensor.

5. Piezo electric detection system for security devices as claimed in preceding Claims, characterised by the use of at least one combination of at least two sensors which are different from each other, the difference being implemented by use of at least one of any combinations of at least one difference in physical dimensions of the said piezoelectric material, at least one difference in kind of the piezoelectric material, at least one difference in physical dimensions of the foundation, at least one difference in shape of the piezoelectric material, at least one difference in shape of the foundation, at least one constructional difference of such sensor.

6. Piezo electric detection system for security devices as claimed in preceding Claims, characterised by a construction of such sensor in the form of plurality of sensors as a multiple sensor consisting of at least two sensors constructed on a common said foundation.

7. Piezo electric detection system for security devices as claimed in preceding Claims, characterised by construction of such sensor situated in the location of said protected object and being a component belonging to the location of the said protected objet and providing the said foundation to such sensor.

8. Piezo electric detection system for security devices as claimed in preceding Claims, cllaracterised by the sensor having the foundation made from at least one electrically conductive material providing the foundation (2) and (7) and one of the said two electrical conductors and which is electrically connecting the piezoelectric material (1) and (S) to the foundation (2) and (7) from which further connection (5b) and (Sc) is being made.

9. Piezo electric detection system for security devices as claimed in preceding Claims characterised as having the sensor situated in the location of the protected object and being a component of the location, where the component is electrically conductive and provides at least one electrical connection between at least two of such sensors.

10. Piezo electric detection system for security devices as claimed in preceding Claims characterised as having at least one of the two said electrical connections from the piezoelectric material of the sensor made of an electrically conductive wire which provides a means of mounting such sensor in the location of the protected object.

11. Piezo electric detection system for security devices as claimed in preceding Claims characterised by the use of at least one such sensor in the said location of the protected object, where the object is protected by at least one sensor situated in the protected location and in physical contact with a component of the protected object.

12. Piezo electric detection system for security devices as claimed in preceding Claims characterised by the use of at least one such sensor in the said location of the protected object, where the object is protected by at least one sensor situated in the protected location arid is not In physical contact with the protected oì)ject, but is in surroundings of it.

13. Piezo electric detection system for security devices as claimed in prceding Claims characterised by the use of such sensor in the said location of the protected object, where the protected situation is a protected object and the said sensor is situated at another object in the path to the said protected object protecting the location around the protected object.

14. Piezo electric detection system for security devices as claimed in preceding Claims, characterised by means of signalling where each output signal is employed as to initiate at least one function providing at least one information on the situation of the protected object.

15. Piezo electric detection system for security devices as claimed in preceding Claims, characterised by means of electrical connection from at least two sensors, where their outputs are electrically connected into at least one electrical channel providing the electrical connection to the processing unit and where the processing unit provides conditioning of such signal and initiates at least one of the functions of such security device.

16. Piezo electric detection system for security devices as claimed in preceding Claims, characterised by the electronic processing of each output signal where such signal is processed by the processing unit, where the processing unit has a means of recognition of such signal characteristics, and where the processed and recognised signal is used to initiate at least one function assigned to that particular output signal and is providing at least one kind of information on the situation related to security of the protected object.

17. Piezo electric detection system for security devices as claimed in preceding Claims, characterised by the electronic processing of each output signal where such signal is processed hy the processing unit, where the processing unit has at least one means of user pre-setting of levels related to recognition of signal characteristics, and where the processed and recognised signal is used to initiate at least one function assigned to that particular output signal and particular presetting and is providing at least one kind of information on the situation related to security of the protected object.

18. Piezo electric detection system for security devices as claimed in preceding Claims, characterised by ability to construct modules providing at least one function of signalling on situation of protected object in combinations of the sensors and the processing units exploiting their ability of the artificial intelligence a particular function as assigned by each user with pre-setting means, the modules constructed as independent stand a lone as complete security system and suitable modules built for integration into existing security systems widening their capability.

19) Piezo electric detection system for security devices as claimed in preceding Claims, characterised by ability to construct the system where the output signals are counted to a predetermined number of counts by the user with pre-settable counter within a predetermined time period before setting off an alarm, the predetermined period of time being determined by a user pre-settable timer, and where at the end of each timing period the timer provides reset signal to provide reset function of the said counter and a where a start of a new timing period of the pre-settable timer is initiated, each time after the predetermined time period expires, by a next output signal from the piezo electric sensor and the first counter starts counting again within the new period of time.

20. Piezo electric detection system for security devices as claimed in preceding Claims, characterised by ability to provide a variety of functions related to security situation where the function are signalling by electrically powered indicators, reporting by telephone and RF transmissions on disturbance in the protected location and the levels and duration of disturbance in stages and in sequence by pre-setting the processing unit by individual users of for providing required assigned functions to particular characteristics of the output signals prior to setting the main alarm functions.