DE202014106128U1 - Cabinet Alarm System - Google Patents

Abstract

A warning alarm system arranged to fit a cabinet, the alarm system comprising: a timer; a first, a second and a third sensor, each sensor being adapted to detect a different physical event to provide a respective first, second and third input, respectively, and means for triggering a warning on successive events: the first one and the second detected input exceeds a respective first and second input threshold value during a first time period; and the third detected input exceeds a third input threshold within a predetermined time interval subsequent to the first time period.

Description

Field of the invention

This invention relates generally to cabinet alarm systems. More particularly, this invention relates to security alarm systems whereby a warning message is provided only when the cabinet is attacked.

background

Ticket and other vending machines are placed in locations to facilitate automated customer transactions and are increasingly appearing at, for example, bus and tram stops and train stations, car parks, shopping malls and shopping streets.

Since these machines are designed to allow automatic transactions, they are typically provided in locations that are not supervised or at least not always supervised. As a result, machines are vulnerable to attack and vandalism, and there is a need to provide electronic alarm systems to detect inappropriate and harmful behavior, loss of machine contents (such as money and inventory) and unavailability to use, expensive cabinets or the like even the complete loss due to the complete removal of the cabinets.

The type of attacks on such machines can be divided into the different types of attacks as follows.

Type 1 - Low impact frustration attacks where intrusion is not the goal and no damage is done to the cabinet.

Type 2 - Vandalism causing physical damage to the cabinet.

Type 3 - Purposeful attempts to gain access and steal the content.

• a) Verwendung eines Sauerstoff-Acetylen- oder Plasmabrenner-Schweißgeräts, um Löcher zu schneiden.
• b) Verwendung eines Winkelschleifers, einer Bohrmaschine oder eines anderen mechanischen Schneidgerätes, entweder elektrisch oder benzinbetrieben, um Löcher zu schneiden.
• c) Verwendung eines Vorschlaghammers oder Fäustels und eines Brecheisenhebels, um zu versuchen, die Tür zu öffnen.
• d) Verwendung eines Fahrzeugs oder ähnlichen Mittels, um den Automaten zu rammen oder von seiner Verankerung zu ziehen.

Type 3 attacks include:

• a) Use an oxygen-acetylene or plasma torch welder to cut holes.
• b) Using an angle grinder, drill or other mechanical cutter, either electric or petrol driven, to cut holes.
• c) Using a sledgehammer or fist and a crowbar lever to try to open the door.
• d) using a vehicle or similar device to ram or pull the machine from its anchorage.

It is desirable to monitor machines to detect the occurrence of an attack and distinguish between the different types of attacks. For example, a Type 1 low impact frustration attack may require some sort of action, while a Type 2 vandal or an Attempted Type 3 Attack would require triggering other reactions.

The cabinets associated with vending and ticket vending machines are significantly thinner and more flexible than an ordinary vault. Furthermore, these cabinets are located in public areas and are potentially exposed to extreme weather conditions.

One concern with monitoring a cabinet is determining when an event is a real attack, rather than identifying something generated by a normal environmental condition and identifying the action required by the nature of the event. This must also be done in noisy and busy environments, such as those found on a platform in a train station where the alarm system is to be installed on a ticket vending machine.

State of the art

There are safety devices and procedures that could be applicable to cabinets. Some relevant examples are:
Chinese utility model CN-U-201695861 for "Burglar Alarm for Safes" by Zongshu,
Chinese patent CN-Y-201297091 for "Electronic Alarm Device for a Safe" by Jiayan et al.,
Japanese patent application JP-A-2003041858 for "Safe with IT function" by Harada,
UK patent application GB-A-2306035 for "Differential Weight Security System" by Williams and Jones,
UK patent GB-B-2360119 for "Sensor Systems" by Williams, Jones and Hutcheson,
UK patent application GB-A-2365187 for "Piezo-electric Sensor and Alarm System" by Williams and Jones,
UK patent application GB-A-2279791 for "Motion Detecting System" from Appleby,
UK patent GB-B-2466721 for "Security System" by Jones,
UK patent application GB-A-2264378 for "Frangible Sensor for a Secure Enclosure" by Morgan,
EP patent application EP-A2-1981010 for "Method of Detecting Lock Bumping" by Smith,
FR patent application FR-A1-2687240 for "Dispositif de protection detectant la solicitation du mecanisme d'une fermeture et generant un signal d'information, d'aleert ou d'alarme" (protection device for detecting the operation of a closure and for providing information, an alarm or a warning signal) .
FR patent application FR-A1-19871106 for "Improvements to Devices Known as Alarm Devices, for Countering Unauthorized Intrusion into Buildings" (improvements to devices known as alarm devices to combat unauthorized intrusion into buildings) from Milly,
US patent application US-A-4772874 for "Keyboard Apparatus" by Hasegawa,
US patent application US-A1-2005 / 0264413 for "Dual Technology Glass Breakage Detector" by Eskildsen, and
US patent application US-A-4383250 for "System for Intrusion Detection" by Galvin

Brief description of the invention

The practice of the present invention for distinguishing a true attack from something generated by a normal environmental condition is to utilize at least two separate techniques that generate separate responses to an attack to increase the confidence level of a true event to a value in which action must be taken. The present invention utilizes existing technology and combines it in a novel and inventive way with other signal processing techniques to detect attacks on cabinets such as ticket vending machines and vending machines.

In this patent, "airborne sound" means sound that travels through the air. An airborne sound sensor is in contact with the air and detects this sound in this air through this contact with the air.

In this patent, "structure-borne sound" means sound traveling through the structure of a cabinet. A structure-borne sound sensor is in contact with the cabinet and detects this sound in the structure of the cabinet through this contact with the cabinet.

In this patent, "distortion" means stress in the cabinet. A "distortion sensor" detects stress in the cabinet. A force applied to the cabinet causes stress in the cabinet. The distortion sensor detects this force by detecting the stress caused by this force.

In this patent, a thermodifferential sensor is a timepiece combined with a thermometer sensitive to the temperature of the air close to the thermometer. The thermal differential sensor detects the time rate of change of the air temperature.

A thermal differential sensor preferably includes a thermometer located in the cabinet to detect the temperature of air in the cabinet.

According to a first aspect of the present invention, an alarm device is arranged to mate with a cabinet, the alarm system comprising: a timer, first, second and third sensors, each sensor adapted to receive a different physical event to provide a respective first, second and third input, respectively, and means for triggering a warning message on the following consecutive events: the first and second detected inputs exceed respective first and second input threshold values during a first time period; and the third detected input exceeds a third input threshold within or after a predetermined time interval subsequent to the first time period.

Any offender who attacks a cabinet can use his method and tools to gain access to the inside of the cabinet. Each method has attack steps. These steps can take place simultaneously, but often the attack steps must be performed in a specific order. Each step can use a specific tool. The alarm alarm system uses three types of sensors. Each sensor is sensitive to a noise, vibration, distortion or temperature change, optical trigger, smell, and so on, that corresponds to a particular physical event. The alert alarm system includes means for triggering the alarm when the particular physical events occur in a particular order. The alarm will only be triggered if the events are within or after predetermined ones Time intervals take place in relation to each other. The order and timing of physical events are indicative of the type of attack the offender uses. Therefore, the alert alarm system can detect and provide an alert for many specific types of attacks.

Preferably, the first sensor is an acoustic sensor that detects an airborne sound and the third sensor is a structure-borne sound sensor that detects sound transmitted from a sound generating device to a cabinet by direct contact between the sound generating device and the cabinet. An offender can attack the cabinet with a grinder or a mechanical cutter. First, the grinder or cutter is turned on and produces a loud, howling airborne sound. The grinding machine is then typically applied to a cabinet wall within a period of one-half second to two seconds. This creates structure-borne noise as the grinder vibrates the wall as its blade begins to cut through it. In the embodiment, the second sensor is a distortion sensor. If the cabinet is attacked with a grinder, a mechanical cutter or a drill, the cabinet is distorted under the force exerted by the tool. Alternatively, in the embodiment, the second sensor may be a temperature sensor. If the cabinet is attacked with a grinder or a drill, the grinding wheel or drill creates friction and sparks that heat the cabinet and are detected by the temperature sensor.

Preferably, the first sensor is an acoustic sensor that detects an airborne sound, and the third sensor is a thermal sensor that detects temperature. A typical attack with a cutting torch begins with the cutting torch being lit. There will be a bang followed by a hissing sound when the burner is lit. After lighting the burner, the offender cuts through the wall with the burner flame. As soon as the flame penetrates inside the cabinet, the sound level of the cutting flame is significantly increased and the temperature in the cabinet rises rapidly. The alert alarm system may distinguish a cutting torch attack from background noise, normal daily temperature changes, and so on, due to its sensitivity to the order and time of physical events associated with this type of attack.

An acoustic sensor is arranged to detect sound in the air inside the cabinet. These internal sensors are hard to manipulate. The hiss of a burner when it is switched on is more difficult to reliably detect than the noise when the flame enters the cabinet. The cabinet is an enclosed space so that the flame within the cabinet makes a very loud noise. The acoustic sensor is preferably located in the cabinet to detect sound in the air within the cabinet.

The thermal sensor preferably comprises a means for measuring the rate of change of temperature. Burner attacks are associated with a rise in the temperature of the air in the cabinet that occurs much faster than the daily variations in temperature due to sunrise, sunset, and weather events.

Preferably, the first sensor is an acoustic sensor that detects airborne sound; the second sensor is a structure-borne sound sensor that detects sound transmitted to the cabinet through direct contact between the sound generating device and the bank from a sound generating device; and the third sensor is a distortion sensor that detects stress changes in the structures of the cabinet as a result of exerting force. An offender may try to pry open the closet door by first hammering a lever into a part of the door to get a point of attachment. The impact or blows of the hammer on the lever produce characteristic airborne sound and structure-borne noise in the cabinet. Typically, the offender applies force to the lever half a second to ten seconds later to try to open the door, causing distortion of the cabinet and door. Alternatively, an offender can attack the cabinet with a grinder. First, the grinder is turned on and produces a loud, howling airborne sound. The grinding machine is then applied to a cabinet wall and produces structure-borne noise when the grinding machine vibrates against the wall. The offender then hits the weakened cupboard to break it open. The impact creates a deflection or stress in a fastener that secures the cabinet to a pedestal.

Preferred is an alarm alarm system arranged to fit a cabinet, the alarm system comprising: a timer; a first, a second and a third sensor, wherein each sensor is adapted to detect a different physical event to provide a respective first, second and third input, respectively, and means for triggering a warning on successive events: the third one detected input exceeds the third input threshold during the first period; and the first and second detected inputs exceed respective first and second input threshold values within a predetermined time subsequent to the end of the first period.

This arrangement of the alarm alarm system is advantageous for the detection of an attack, in which only at and then drilled into the cabinet. When a cabinet is attacked with a drill, the movement of the drill against the cabinet creates distortion of the cabinet, impaction of the drill bit, and airborne noise from the drill motor and metal cutting. A typical sequence of events is distortion, very quickly followed by structure-borne noise and airborne sound. In practice, distortion, structure-borne sound and airborne sound can occur simultaneously and we prefer to see if they are present for a predetermined duration to trigger an alarm.

Preferably, the first sensor is an acoustic sensor that detects airborne sound; the second sensor is a structure-borne sound sensor that detects sound transmitted to a cabinet from a sound generating device through direct contact between the sound generating device and the cabinet; and the third sensor is a distortion sensor that detects stress changes in the structures of the cabinet as a result of exerting force. A culprit may try to drill into the cabinet. The drilling and penetration of the drill bit into the cabinet generates distinctive airborne and structure-borne noise in the cabinet, and at the same time creates distortions due to the force exerted against the cabinet by the movement of the drill bit. These conditions are for a short period of time.

As a preferred alternative, the first sensor is a distortion sensor that detects stress changes in the structures of the cabinet as a result of exerting force; the second sensor is an acoustic sensor that detects airborne noise; and the third sensor is a structure-borne sound sensor that detects sound transmitted to a cabinet from a sound generating device through direct contact between the sound generating device and the cabinet. A culprit may try to drill into the cabinet. The force exerted by the drill bit when moving against the cabinet first creates distortions, and shortly thereafter, the drilling and penetration of the drill bit into the cabinet generates characteristic airborne and structure-borne noise.

An advantage of the invention is that substantially any noiseless attack can be detected with a hand drill. Once the drill bit is slightly moved against the cabinet, distortion of the cabinet can be detected by means of a distortion sensor. The then manually rotated drill bit is almost noiseless, since only a small airborne sound is produced in the air. However, the rotation of the drill bit causes vibrations in the cabinet that are detectable by a structure-borne sound sensor fixed to the cabinet. However, it is likely that even before the start of a hand drill attack, the attackers will generate some airborne noise around the cabinet as they position themselves and get their equipment ready. To counteract the attack with a hand drill or an electric drill, an alert device arranged to fit a cabinet is preferred, the alarm system comprising: a timer; a first, a second and a third sensor, each sensor being adapted to detect a different physical event to provide a respective first, second and third input, respectively, and means for triggering a warning on successive events: the first one detected input exceeds the first input threshold during the first period; and the second and third detected inputs simultaneously exceed a respective second and third input threshold values, respectively, after a predetermined period subsequent to the first time period, wherein the first sensor is an acoustic sensor detecting noises in the air, the second sensor is a structure-borne sound sensor Noise is detected, which occurs when a device is applied to the cabinet, that penetrates the cabinet with a rubbing element, so that the noise is transmitted through the cabinet, and the third sensor is a distortion sensor, the changes in stress in the structures of the cabinet recognizes.

Preferably, the alert device comprises a processor to interpret the inputs from the first, second and third sensors. A processor may be a programmable device. Thus, if an offender manages to break into a cabinet once, the sequence of events can be programmed into the processor while the attack is taking place. The processor may be programmed to trigger the alarm the next time an offender attempts an attack indicated by the same physical events detected in the same order and within or after the same time intervals with respect to each other.

The microprocessor is programmable such that each sensor can be considered as the first, second or third sensor. For example It is advantageous if the acoustic sensor is regarded as the first sensor to detect some variants of the attack and the distortion sensor or another sensor is considered as a first sensor to detect other attack variants as the first sensor. Thus, this embodiment is advantageous to equip the alarm system with the ability to detect various types of attack with the three sensors.

To record the order of events of an attack and determine their order, the alarm system preferably additionally includes an acoustic sensor, and further includes a sound recording device arranged to record airborne sound during the events that trigger the alarm.

By monitoring the events in this manner, it is advantageous to provide the alarm only and to record the airborne noise if a malicious attack is made to damage or access the cabinet. The alert device preferably comprises a time-measuring means with recording means for recording signals from the sensors. The timing means is preferably preset or may be adjusted to record the signals for up to one minute from the beginning of a physical event. Anyone attempting to gain access to the cabinet will cause significant damage in a minute and create concomitant recordable events. Even more preferred is the period of half to 20 seconds. A grinder or cutting torch can cut into a cabinet in 2 to 20 seconds, and limiting the time interval requires less memory to record the sensor signals.

For example, the alert device preferably includes a processor for interpreting the inputs from the first, second, and third sensors when (i) the airborne sound sensor and the structure-borne sound sensor provide first and second inputs that exceed the respective first and second input thresholds in the first time period, respectively ; and after the predetermined time interval; (ii) the distortion sensor provides a third input exceeding the third input threshold and also for triggering the alert if: (iii) the structure-borne sound sensor provides a second input exceeding the second threshold in the first time period; and after the predetermined time interval, (iv) the distortion sensor provides a third input that exceeds the third input threshold; and also to trigger the warning message if: (v) the airborne sound sensor provides a first input that exceeds the first threshold in the first time period; and after the predetermined time interval; (Vi) the distortion sensor provides a third input that exceeds the third input threshold. The first input threshold of the event (i) is preferably different from the first input threshold of the event (v). The second input threshold of the event (i) is preferably different from the second input threshold of the event (iii). The third input thresholds of events (ii), (iv), and (vi) are preferably all different.

In certain cases, however, the airborne sound thresholds are the same, the structure-borne sound thresholds are equal and certain force thresholds are equal. Advantageously, this means that the cabinet alarm system can be individually adapted to trigger the warning message in an attack with a certain type of tool or combination of tools.

The first sensor is preferably an airborne sound sensor, the airborne sound in the frequency range and airborne sound generated by a rotary grinding or cutting machine in the frequency range generated by a cutting torch, and airborne sound and sound generated by the impact of metal on metal Air inside the cabinet recognizes.

The second sensor is preferably a structure-borne sound sensor, which detects structure-borne sound from a sound-generating device by direct contact between the sound-generating device and the cabinet to the cabinet. It is preferably recognized by the frequency range of structure-borne noise as a result of striking metal on metal and structure-borne sound produced by a rotary grinding and cutting machine.

The cabinet alarm system preferably provides a warning message in response to the occurrence of an attack event that causes great distortion of the structure of the cabinet without generation of significant sound.

• (i) die zeitliche Änderungsrate der Krafteingabe übersteigt jeweils eine erste zeitliche Änderungsrate des Kraftschwellenwerts während des ersten Zeitraums; und in dem vorherbestimmten Zeitintervall,
• (ii) die Kraft übersteigt einen vierten Kraftschwellenwert.

As an alternative embodiment of the sensors for detecting various types of attacks, the first sensor is preferably a distortion sensor which detects a force input in conjunction with time counted by the timer and the events are:

• (i) the time rate of change of the force input exceeds a first time rate of change of the force threshold during the first period; and in the predetermined time interval,
• (ii) the force exceeds a fourth force threshold.

For example, a typical attack detected by these events would be the case where a culprit wraps a chain around the closet or attaches the chain to the cabinet. The offender attaches the chain to a vehicle or winch and pulls the cabinet away from its connection to the pedestal. When the vehicle is driven away from the cabinet, the chain reaches its limit and makes a sudden jerk on the cabinet. There is a very high rate of change in the force applied to the cabinet with respect to time. Sometimes the cabinet is repeatedly pulled jerkily to release it from the socket. Therefore, this type of attack can be detected by one or more rapid changes in force resulting in weaknesses in the attachment of the cabinet to the pedestal, followed by a large force to disengage the cabinet. The repeated jerks provide an early warning of the beginning of an attack.

Once the alert is provided, it preferably lasts while all detected inputs exceed their respective input thresholds. Therefore, if the attack is aborted or completed, the alert will no longer be deployed and will not disturb anyone or continue to send a signal to a monitoring center that an attack is in progress. Alternatively, the triggering means may be arranged to continue to provide the warning message when all physical inputs have taken place in a preselected order and within or after a preselected interval with respect to each other. Therefore, even if the offender stops or completes the attack, the alert will continue to sound or flash, or continue to be reported to a monitoring center or people near the closet. The warning message may be distributing the culprit.

The means for providing a warning message is preferably suitable for connection to a wireless or wired transmitter.

Preferably, any or all of the airborne sound thresholds, body sound thresholds and force thresholds may be set by a user either prior to installation of the alarm in the cabinet or after installation of the alarm in the cabinet or both before and after it by a local user or a remote user become.

Advantageously, the cabinet alarm system is adapted to provide no warning when a cabinet is exposed to normal sound and handling.

The alarm system preferably provides a warning only when a certain sequence of events occurs that is indicative of an attack on the cabinet.

When the alert is provided, it preferably lasts until the events that triggered the alarm cease, or an acknowledgment of the alert message is returned to the cabinet alarm system or lasts for a predetermined time after the alert message is first posted.

There is preferably a means by which the user can set the predetermined time.

In order that the present invention may be well understood, it will be further explained by way of example by the following description, taken in conjunction with the annexed drawings, in which:

Brief description of the figures

1 is a cabinet that includes a door swinging on hinges.

2 is a time trace of sound detected by an airborne sound sensor and a structure-borne sound sensor before and during an attack on a cabinet with a mechanical grinder or a mechanical cutter.

3 is a time trace of sound detected by an airborne sound sensor and the temperature of the air in a cabinet before and during an attack on the cabinet with a hot gas or plasma cutting torch.

4 is a time trace of the force detected by a distortion sensor and the sound detected by a sound sensor before and during a lever attack.

LIST OF REFERENCE NUMBERS

10

cabinet

15

cabinet door

16

Cabinet door hinge

20

base

31, 32, 33

cabinet supports

40

Distance between cabinet and pedestal

50

microphone

60

temperature sensor

80

distortion sensor

Detailed description of preferred embodiments of the invention

1 shows a cupboard 10 , the one door 15 Includes hinges 16 swings.

The cupboard 70 is made up of four props 31 . 32 . 33 and 34 (not shown) over a pedestal 20 supported and kept at a distance from it. Since the supports hold the cabinet above the pedestal, there is a gap or gap between the bottom of the cabinet and the pedestal 40 , The gap allows the cabinet to move on the supports when external force is applied to the cabinet without the cabinet touching the base.

There is a microphone in the cabinet 50 to detect sound that travels through the air in the cabinet before it reaches the microphone. The microphone is an airborne sound sensor.

There is a temperature sensor in the cabinet 60 to detect the temperature of the air in the cabinet. The temperature sensor 60 is combined with a clock (not shown) to produce a temperature differential sensor to detect the rate of change of air temperature in the cabinet.

On the cabinet is a structure-borne sound sensor 70 appropriate.

There is a distortion sensor on the cabinet 80 attached, wherein the distortion sensor detects the distortion of the bottom of the cabinet due to a force exerted on the exterior of the cabinet force.

The pillars 31 . 32 . 33 and 34 and the gap 40 give the ground the freedom to distort itself under an applied force.

The present invention combines sound recognition, force detection and detection techniques. By identifying the airborne and / or structure-borne noise signal properties and the structural deformation produced by various types of cabinet attack, some or all of these signals may be interpreted by a control microprocessor to determine the type of attack.

For example, when a crowbar is hammered into the door opening to provide a starting point for levering the cabinet door, characteristic airborne sound signals and very short structure-borne sound signals occur from the hammer blows, followed by deformation of the structure as the lever starts. A refinement of this process is to count the number of hammer strokes so that a minimum number must be registered before the alarm is triggered by the subsequent lever.

In the case of attacks with cutting torches and angle grinders / cutters, it is typical that the cutting device is turned on and allowed to run for one second before it is inserted into the cabinet to be cut and, of course, that noise continues during the cutting process.

In the case of the angle grinder / cutter, this produces a high level of structure-borne noise as soon as the cutting disc is brought into contact with the cabinet and, if preceded or accompanied by suitable airborne sound, a serious attack is suspected. Another third sensor that detects a third physical event provides further evidence that an attack is taking place.

2 shows a typical time trace of sound before and during an attack with a grinder from the airborne sound sensor 50 and the structure-borne sound sensor 70 is recognized. The time lane is a record of that from the airborne sound sensor 50 generated airborne sound signal and in the same diagram a record of the structure-borne sound sensor 70 generated structure-borne sound signal.

Almost always, an attacker of an attack on a cabinet, just before he actually attacks a cabinet with a grinder or cutting device, turns on the device. Grinders usually include a rotating blade driven by a loud electric motor or a loud pneumatic motor. The loud sound is transmitted through the air inside and outside the cabinet and is received and detected by the airborne sound sensor. The airborne sound sensor is preferably mounted inside the cabinet. This location prevents the offender from obscuring the airborne sound sensor with a device for attenuating the sound.

2 shows the increase in the time track of the sound detected by the airborne sound sensor when the grinding machine is turned on. The level of sound generated by the grinder rises above the airborne sound threshold, as shown.

Almost always, the offender of an attack, shortly after he turns on a grinder, begins to cut through the cabinet by bringing the blade into contact with the cabinet. The cutting wheel transmits vibrations to the cabinet, which are transmitted through the walls of the cabinet directly from the grinding machine to the structure-borne sound sensor, which detects the structure-borne sound.

As in 2 shown, is the transmitted from the grinding machine to the cabinet structure-borne sound above the structure-borne sound threshold after the grinder touches the cabinet. Thus, the structure-borne noise increases within a very short time, after the airborne noise above the airborne sound threshold, above the structure-borne sound threshold. This very short time is usually between a fraction of a second and a few seconds. Mostly it's between half a second and two seconds.

If the airborne sound sensor detects a sound that is above the airborne noise threshold for a very short time before the acoustic emission sensor detects sound above the structure-borne noise threshold, there is a very high probability that the cabinet will be attacked by a culprit using a grinder. Therefore, when this sequence of events occurs, the cabinet alarm provides a warning of the attack.

In the case of a cutting torch, the airborne sound detected prior to detecting a rapid rise in the air temperature in the cabinet when the cutting flame penetrates the cabinet skin may be used as an indication of a serious attack. The level of airborne sound in the cabinet is also greatly enhanced as the cutting flame penetrates the cabinet skin, providing an alternative event that forms part of a serious attack. A third sensor that can detect a third physical event can provide a higher degree of confidence that an attack has occurred.

3 is a time trace of sound detected by an airborne sound sensor and the temperature of the air in a cabinet before and during an attack on the cabinet with a hot gas cutting torch.

Just before a cutting torch cuts through a cabinet, the air in the cabinet is almost always relatively cool and quiet.

A cutting torch produces a whistling or hissing sound. Until the flame cuts through the cabinet, the noise of the cutting torch may be below the airborne sound threshold for the cutting torch. However, when the flame cuts into the interior of the cabinet, the whistling or hissing noise of the burner in the cabinet is amplified and is produced by the airborne sound sensor 50 detects and exceeds the airborne noise threshold.

Until the flame cuts through the cabinet, the air in the cabinet is relatively cool. Since the air in the cabinet is in a confined space, the temperature of the air begins to increase rapidly as the burner flame cuts through the cabinet to the interior. Advantageously, the temperature rise rate of this air due to a burner flame in the interior of the cabinet is much higher than due to solar radiation on the outside of the cabinet. Therefore, a time trace is that of the temperature sensor 60 inside the cabinet, the temperature, which rises faster than the temperature rise threshold, indicates that a flame from a cutting torch has cut into the cabinet. This is in 3 through the time track of the temperature sensor 60 in the cabinet detected temperature of the air shown.

When the cabinet alarm system detects airborne sound and temperature changes over time, as in 3 As shown, there is a high probability that a culprit has attacked the cabinet with a hot gas cutting torch. This is the chronological sequence of events in which the following occurs: First, the temperature within the cabinet is almost constant or changes only gradually with the weather or night-to-day transition and the sound level in the cabinet is below the airborne sound threshold for a cutting torch flame, then, second, the sound level in the cabinet suddenly rises above the airborne sound threshold for a torch flame and, in addition, the temperature rise rate in the cabinet is above the threshold of the temperature rise rate for a torch flame.

An alternative form of attack in which no significant sound levels may be present is an attempt to remove the cabinet from its fixtures by ramming or pulling it down with powerful equipment. Ticket and other vending machines are bolted using multiple ground screws, usually one in each corner 31 . 32 . 33 and 34 , Any attempt to forcibly remove the unit by ramming or clamping a belt or chain around it and pulling it with a vehicle or other device results in significant deformation of the cabinet. This is from the distortion sensor 80 recognized as a claim. By identifying appropriate monitoring sites and setting appropriate signal level thresholds, real attacks can be distinguished from environmental events such as high winds. The sensitivity of detecting this deformation is improved when the cabinet only by the screws 31 . 32 . 33 and 34 is held. A gap 40 of about 2 mm between the bottom of the cabinet and its base or floor mounting is ideal, allowing the entire weight of the cabinet between the screws 31 . 32 . 33 and 34 is distributed.

By providing various outputs, the cabinet alarm can identify the likely nature of an attack to trigger appropriate responses.

Another improvement of the cabinet alarm system is the recording of acoustic information. Rolling 30 seconds of sound is recorded on a first-in-first-out basis, stopping recording when a significant alarm is generated for later retrieval or transmission as a file over the Internet or mobile networks.

The invention has been described by way of example only. The invention will be further clarified and further explained in the appended claims. The claimed features may be replaced by substantially equivalent features without departing from the scope of the claims.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• CN 201695861 U [0012]
• CN 201297091 Y [0012]
• JP 2003041858A [0012]
• GB 2306035 A [0012]
• GB 2360119 B [0012]
• GB 2365187A [0012]
• GB 2279791 A [0012]
• GB 2466721 B [0012]
• GB 2264378A [0012]
• EP 1981010 A2 [0012]
• FR 2687240 A1 [0012]
• FR 19871106 A1 [0012]
• US 4772874A [0012]
• US 2005/0264413 A1 [0012]
• US 4383250 A [0012]

Claims (16)

Alert alarm system arranged to fit a cabinet, the alarm system comprising: a timer; a first, a second and a third sensor, each sensor being adapted to detect a different physical event to provide a respective first, second and third input, respectively, and means for triggering a warning on successive events: the first one and the second detected input exceeds a respective first and second input threshold value during a first time period; and the third detected input exceeds a third input threshold within a predetermined time interval subsequent to the first time period. Alert alarm system arranged to fit a cabinet, the alarm system comprising: a timer; a first, a second and a third sensor, wherein each sensor is adapted to detect a different physical event to provide a respective first, second and third input, respectively, and means for triggering a warning on successive events: the third one detected input exceeds the third input threshold during the first period; and the first and second detected inputs exceed respective first and second input threshold values within a predetermined time subsequent to the end of the first period. A warning alarm system arranged to fit a cabinet, the alarm system comprising: a timer; a first, a second and a third sensor, each sensor being adapted to detect a different physical event to provide a respective first, second and third input, respectively, and means for triggering a warning on successive events: the first one detected input exceeds a first input threshold during a first time period; and the second and third detected inputs simultaneously exceed a respective second and third input threshold values after a predetermined period of time subsequent to the first period. An alarm system according to claim 1 or 2, wherein the first sensor is an acoustic sensor for detecting noises in the air and the third sensor detects sound coming from a sound generating device through direct contact between the sound generating device and the cabinet is transferred to the cabinet. Alarm system according to claim 1 or 2, wherein the first sensor is an acoustic sensor to detect noise in the air and the third sensor is a thermal sensor which detects the temperature of the air in the cabinet. Alarm system according to claim 5, wherein the thermal sensor comprises means for measuring the temporal temperature change rate. Alarm device according to claim 5, wherein the second sensor detects sound transmitted from a sound generating device to the cabinet by direct contact between the sound generating device and the cabinet. An alarm system according to claim 1 or 2, wherein the first sensor is an airborne sound sensor for detecting noises in the air; the second sensor detects sound transmitted from a sound generating device to the cabinet through direct contact between the sound generating device and the cabinet; and the third sensor detects stress changes in the structures of the cabinet. Alarm system according to claims 4 to 8, wherein the airborne sound sensor is arranged to detect noise in the cabinet. Alarm system according to one of the preceding claims, wherein the predetermined time interval is between half a second and two seconds. Alarm system according to one of the preceding claims, wherein the predetermined time is between half and ten seconds. An alarm system according to any one of the preceding claims, wherein the warning message, once provided, lasts while all detected inputs exceed their respective input thresholds. Alarm device according to one of the preceding claims, wherein the means for providing a warning message for connecting to a wireless or wired transmitter is suitable. Alarm device according to one of the preceding claims, wherein the alarm system comprises an acoustic sensor, further comprising a sound recording device, which is arranged to record airborne sound during the events that trigger the alarm. An alarm system according to claim 14, comprising a timing device for recording Signals from all signals for at least 30 seconds after the first physical event is detected. A cabinet comprising an alarm system according to any one of the preceding claims.

Images