EP0811212B1 - A monitoring device - Google Patents
A monitoring device Download PDFInfo
- Publication number
- EP0811212B1 EP0811212B1 EP96901078A EP96901078A EP0811212B1 EP 0811212 B1 EP0811212 B1 EP 0811212B1 EP 96901078 A EP96901078 A EP 96901078A EP 96901078 A EP96901078 A EP 96901078A EP 0811212 B1 EP0811212 B1 EP 0811212B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- state
- monitoring device
- changes
- detected
- change
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B13/00—Burglar, theft or intruder alarms
- G08B13/02—Mechanical actuation
- G08B13/14—Mechanical actuation by lifting or attempted removal of hand-portable articles
- G08B13/1409—Mechanical actuation by lifting or attempted removal of hand-portable articles for removal detection of electrical appliances by detecting their physical disconnection from an electrical system, e.g. using a switch incorporated in the plug connector
- G08B13/1418—Removal detected by failure in electrical connection between the appliance and a control centre, home control panel or a power supply
Definitions
- THIS INVENTION relates to a monitoring device for monitoring an apparatus having first and second states and for providing an output signal indicating that the apparatus has undergone a pre-determined sequence of changes of state.
- Prior art document WO-A-8 501 708 discloses an anti-theft ignition system in which the ignition system is enabled once a predetermined series of pulses are input from the ignition switch and compared with a stored code.
- the monitoring apparatus of the present invention finds particular application as a security or anti-theft device for monitoring changes in the state of an apparatus to be protected and providing an alarm signal in the event of unauthorised removal of the apparatus.
- the monitoring device may provide an alarm signal in the event that the equipment is disconnected from its power source and moved without a pre-determined sequence of connections to and disconnections from its power source having first been carried out.
- the present invention provides a monitoring device for monitoring an apparatus having first and second states, comprising: detecting means for detecting each change of state of the apparatus between its first and second states; timing means for measuring the duration between successive changes in the state of the apparatus as detected by the detecting means; memory means for storing first, second and third pre-determined durations; comparing means for comparing the timing of detected changes in the state of the apparatus and delivering an output signal in the event that first and second changes of state of the apparatus are detected within a duration not exceeding the first pre-determined duration, a third change of state is detected after the second change of state at a time corresponding to the second pre-determined duration and a fourth change of state is detected after the third change of state at a time corresponding to the third pre-determined duration; and means for emitting timing signals during the second and third durations after detecting the second and third changes of state respectively.
- an anti-theft device embodying the present invention comprises a monitoring device 1, a trembler unit 2 and an alarm unit 3 and serves to protect an electrical or electronic apparatus 4 against unauthorised removal.
- the monitoring device has a pair of input terminals 1A and 1B which are respectively connected to the power lines 4A and 4B of the apparatus 4 to be protected so as to sense the voltage applied to the apparatus 4.
- the voltage on the power lines 4A and 4B may vary from 1.5 to 350V AC or DC.
- the trembler unit 2 is incorporated in the monitoring device 1 which is mounted on the apparatus 4 to be protected and includes a trembler switch 5 which operates in response to movement of the apparatus 4 and a trembler circuit 6 providing a motion-detected signal on an output line 7 of the trembler unit.
- the motion detected signal delivered by the trembler unit is applied to an input 8 of the alarm unit 3 via a disarm latch 9 which, in its normal condition, connects the output line 7 to the input line 8, thereby passing the output signal of the trembler unit 2 to the alarm unit 3.
- the alarm unit 3 comprises a sound control 10 connected to the input line 8 and having an output line 11 connected to a piezo-electric buzzer 12.
- the monitoring device 1 comprises a voltage rectifier 14 connected to the input terminals 1A and 1B and having a charger output 15 connected to a battery charger 16 arranged to charge a battery 13 constituting an internal power supply of the monitoring device 1.
- the voltage rectifier 14 charges up the battery 13 via the charger 16.
- the equipment 4 is not powered, i.e. switched off, the battery 13 provides operating power for the device.
- a signal output of the rectifier 14 is optically coupled to the input of a pulse detector 17 by means of an opto-isolator which comprises a transmitter in the form of a light-emitting diode 18 connected to the signal output of the rectifier and a receptor in the form of a light-sensitive transistor 19 connected to the input of the pulse detector 17.
- the output line 20 of the pulse detector 17 is connected via a hold and extend circuit 21 to a counter 22 which receives clock pulses from an internal clock 23 of the monitoring device 1.
- the counter 22 is connected to first and second latches 24 and 25 and has a first output 26 connected to a sequence correct counter 27.
- a second output 28 is connected to a second input of the sound control 10 of the alarm unit 3.
- the sequence correct counter 27 has a first output 29 connected to a control input of the disarm latch 9 and a second output 30 connected to a third input of the sound control 10 of the alarm unit 3.
- the pulse detector 17 detects each change in the power status of the apparatus 4 between its powered and unpowered states and delivers an output signal on its output 20 to hold and extend circuit 21 which is set to an interpretation state if it receives two output signals from the detector 17 within a first pre-determined duration which may be selected to be between 0.1 seconds and 1 hour but is typically of the order of five seconds.
- the first and second latches 24 and 25 respectively store second and third pre-determined durations for comparison with counts accumulated in the counter 22 during operation of the device as hereinafter described.
- the sequence correct counter 27 applies a disabling signal on its output 30 to the sound control 10 of the alarm unit 3 when the apparatus 4 is connected to its power source and applies an enabling signal to the sound control 10 on output 30 when the apparatus 4 is disconnected from its power source.
- the anti-theft device described above with reference to Figure 1 operates so that activation of the alarm unit 3 occurs in the event that the apparatus 4 is moved whilst the equipment is disconnected from the power supply without the power supply to the apparatus 4 having first been subjected to a coded sequence of on/off states.
- the output 30 of the correct sequence counter 27 disables the sound control 10 of the alarm unit 3 and movement of the apparatus 4, resulting in movement of the trembler unit 2, does not activate the piezo-electric buzzer 12 of the alarm unit.
- the apparatus 4 must be first subjected to a coded sequence of connections and disconnections of its power supply in order to render the disarmed latch 9 operative to disconnect the alarm unit 3 from the trembler unit 2, since the output signal on line 30 from the sequence correct counter 27 will enable the sound control 10 of the alarm unit 3 on disconnection of the power from the apparatus 4.
- the first step in performing the coded sequence of changes in the power status of the apparatus 4 is to switch the apparatus on and then off within a period of time which does not exceed the first pre-determined duration set by the pulse detector unit 17. This is represented by the pulse 31 in diagram 3a of Figure 3. Detection of pulse 31 by hold and extend circuit 21 at its input causes the circuit 21 to enter its interpretation state as shown at 32 in diagram 3b of Figure 3. After a pre-determined time delay determined by circuit 21 and selectable between 0 seconds and 1 hour, the counter 22 is started by a signal from the circuit 21 as indicated at 33 in diagram 3c of Figure 3.
- the counter 22 provides an output on line 28 to the sound control 10 of the alarm unit 3 to cause the piezo electric buzzer 12 of the alarm unit to emit timing signals in the form of a regular series of short sounds or beeps as indicated at 35 on diagram 3d of Figure 3.
- the power supply is again switched on as indicated at 36 in diagram 3a of Figure 3.
- the circuit 21 stops the counter 22 and the counter then compares the count at this time with the second pre-determined duration set by latch 24 and, if it corresponds, a first correct sequence pulse is delivered to the correct sequence counter 27 on output line 26 of the counter 22 as shown at 37 in diagram 3e of Figure 3.
- the counter 22 is again started as indicated at 36 in diagram 3c of Figure 3 and the piezo electric buzzer 12 emits a further series of beeps 35.
- the apparatus 4 is again switched off as indicated at 38 in diagram 3a of Figure 3, thereby stopping the counter 22 as indicated at 39 in diagram 3c of Figure 3 and stopping the emission of beeps by the piezo electric buzzer 12. If the count in the counter 22 at this time corresponds to the third pre-determined duration stored in latch 25, the counter delivers a second correct sequence pulse on its output 26 to the correct sequence counter 27 as indicated at 40 in diagram 3e of Figure 3.
- the correct sequence counter 27 Upon receipt of this second correct sequence pulse 40, the correct sequence counter 27 delivers a signal on its output 29 to operate the disarm latch 9 as indicated at 41 in diagram 3f of Figure 3, so as to prevent output signals from the trembler unit 2 from reaching the alarm unit and thereby enabling movement of the disconnected apparatus 4 without activation of the alarm unit 3.
- This alarm disarmed state is preferably indicated by the device 1 emitting, for example, five short tones.
- the disarm latch 9 will be in its normal condition and the alarm unit 3 will be activated by the trembler unit 2.
- the device 1 When the power to the apparatus 4 is disconnected, the alarm not being disarmed, the device 1 will emit, for example, three short tones - an alarm active indication. This warns, for example, a shop assistant that movement of the apparatus 4 in this condition would trigger the trembler to cause an alarm condition.
- monitoring device 1 is described as monitoring the voltage on the power lines 4A and 4B, it is envisaged that the device could equally be arranged to monitor current, for example in the range of 1mA to 1A.
- the above device 1 has been described as having its inputs 1A and 1B connected to the power lines of the apparatus 4, the inputs may be directly or indirectly coupled to the power lines or indeed signal lines of the apparatus 4.
- the alarm unit 3 can be activated by disconnection of the apparatus 4 from its power source and unauthorised removal of the apparatus 4, the alarm can be simply de-activated merely by re-applying power to the apparatus to the power supply.
- FIG. 2 shows the monitoring device 1 embodying the present invention incorporated in another anti-theft device which also includes a tamper system comprising, for example, a light-sensitive resistor 50 provided inside a housing of the device and connected to the disarm latch 9, so that illumination of the resistor 50, resulting for example from a person tampering with the housing of the device or the equipment in which the device is installed, will cause an output signal to be delivered to the disarm latch 9 and thereby activate the alarm.
- a tamper system comprising, for example, a light-sensitive resistor 50 provided inside a housing of the device and connected to the disarm latch 9, so that illumination of the resistor 50, resulting for example from a person tampering with the housing of the device or the equipment in which the device is installed, will cause an output signal to be delivered to the disarm latch 9 and thereby activate the alarm.
- a signal applied to input 51 of the device 1 determines whether the device is in a monitoring state to monitor change of the power states of the apparatus 4 or is in a programming state in which selected pre-determined periods and a delay period may be programmed into the latches 24 and 25 and the circuit 21 via inputs 52-55.
- a signal applied to input 56 of device 1 selects whether the presence or absence of voltage or current determines the change of state periods.
- the tamper system may be provided as a separate unit located externally of the housing of the device 1.
- This tamper system can be disarmed by entering an appropriately coded sequence through the power lines of the apparatus 4 being monitored. Should the tamper system be activated, the switching of the apparatus 4 being monitored to an on state will not silence the alarm. The internal power source of the monitoring device 1 must be removed, in this case, to silence the tamper alarm.
- the buzzer 12 has two levels of output an attenuated level and an alarmed level.
- the attenuated level is muted compared to the alarmed level.
- the attenuated level is used for signalling all beeps, tones and indications.
- the alarm level is used only when the unit is activated as an alarm.
- a monitoring device or anti-theft device embodying the present invention may be incorporated during manufacture into an apparatus to be monitored or may be provided as an attachment thereto.
- the device 1 is preferably provided with a battery monitor which generates two tones intermittently over a designated period should the internal power supply, the battery 13, of the device 1 fall below a certain level.
- the device 1 When the device 1 is initially powered up and is not connected to the apparatus 4 being monitored or no signal has yet been received by the device 1 from the apparatus 4, then the device is in a so-called 'test' state. This state is terminated when a signal from the apparatus 4 being monitored is first received.
- the device 1 When the device 1 is in the 'test' state, it generates test tones upon activation of various signals. For example, when the alarm detection circuit is activated (e.g. by triggering the trembler) it generates a series of tones. This series of tones is extended should the tamper system also be activated.
- the device 1 may be placed in a programming state either by initiation by an external trigger or automatically when the device 1 is first in the disarmed state.
- the device has a default code sequence which is accepted as the code for the device. Should the user of the device allow the disarming state to time out (time-out occurring when the device generates the first sequence of tones and the equipment does not change state during this period), then the default code sequence is adopted.
- a monitoring device embodying the present invention presents the great advantage that it is armed and disarmed merely by connecting and disconnecting its power supply and does not require the use of a separate key switch for arming and disarming the alarm as required by presently available anti-theft devices used to protect such apparatus.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Burglar Alarm Systems (AREA)
Abstract
Description
- THIS INVENTION relates to a monitoring device for monitoring an apparatus having first and second states and for providing an output signal indicating that the apparatus has undergone a pre-determined sequence of changes of state. Prior art document WO-A-8 501 708 discloses an anti-theft ignition system in which the ignition system is enabled once a predetermined series of pulses are input from the ignition switch and compared with a stored code.
- The monitoring apparatus of the present invention finds particular application as a security or anti-theft device for monitoring changes in the state of an apparatus to be protected and providing an alarm signal in the event of unauthorised removal of the apparatus. In the case of electrically operated apparatus, the monitoring device may provide an alarm signal in the event that the equipment is disconnected from its power source and moved without a pre-determined sequence of connections to and disconnections from its power source having first been carried out.
- In its broadest aspect, the present invention provides a monitoring device for monitoring an apparatus having first and second states, comprising: detecting means for detecting each change of state of the apparatus between its first and second states; timing means for measuring the duration between successive changes in the state of the apparatus as detected by the detecting means; memory means for storing first, second and third pre-determined durations; comparing means for comparing the timing of detected changes in the state of the apparatus and delivering an output signal in the event that first and second changes of state of the apparatus are detected within a duration not exceeding the first pre-determined duration, a third change of state is detected after the second change of state at a time corresponding to the second pre-determined duration and a fourth change of state is detected after the third change of state at a time corresponding to the third pre-determined duration; and means for emitting timing signals during the second and third durations after detecting the second and third changes of state respectively.
- In order that the present invention may be more readily understood, embodiments thereof will now be described, by way of example, with reference to the accompanying drawings, in which:
- Figure 1 is a schematic block diagram of a monitoring device embodying the present invention incorporated in an anti-theft device connected to an apparatus to be protected against unauthorised removal;
- Figure 2 is a schematic block diagram of a monitoring device embodying the present invention incorporated in another anti-theft device; and
- Figure 3 is a timing diagram illustrating the timing of signals in an anti-theft device incorporating a monitoring device embodying the invention.
-
- Referring firstly to Figure 1, an anti-theft device embodying the present invention comprises a
monitoring device 1, atrembler unit 2 and analarm unit 3 and serves to protect an electrical or electronic apparatus 4 against unauthorised removal. - The monitoring device has a pair of
input terminals 1A and 1B which are respectively connected to thepower lines power lines - The
trembler unit 2 is incorporated in themonitoring device 1 which is mounted on the apparatus 4 to be protected and includes atrembler switch 5 which operates in response to movement of the apparatus 4 and a trembler circuit 6 providing a motion-detected signal on anoutput line 7 of the trembler unit. The motion detected signal delivered by the trembler unit is applied to an input 8 of thealarm unit 3 via adisarm latch 9 which, in its normal condition, connects theoutput line 7 to the input line 8, thereby passing the output signal of thetrembler unit 2 to thealarm unit 3. - The
alarm unit 3 comprises asound control 10 connected to the input line 8 and having anoutput line 11 connected to a piezo-electric buzzer 12. - The
monitoring device 1 comprises a voltage rectifier 14 connected to theinput terminals 1A and 1B and having acharger output 15 connected to abattery charger 16 arranged to charge abattery 13 constituting an internal power supply of themonitoring device 1. When the apparatus 4 is powered, i.e. switched on, the voltage rectifier 14 charges up thebattery 13 via thecharger 16. When the equipment 4 is not powered, i.e. switched off, thebattery 13 provides operating power for the device. - A signal output of the rectifier 14 is optically coupled to the input of a pulse detector 17 by means of an opto-isolator which comprises a transmitter in the form of a light-
emitting diode 18 connected to the signal output of the rectifier and a receptor in the form of a light-sensitive transistor 19 connected to the input of the pulse detector 17. Theoutput line 20 of the pulse detector 17 is connected via a hold and extendcircuit 21 to acounter 22 which receives clock pulses from aninternal clock 23 of themonitoring device 1. Thecounter 22 is connected to first andsecond latches first output 26 connected to a sequencecorrect counter 27. Asecond output 28 is connected to a second input of thesound control 10 of thealarm unit 3. The sequencecorrect counter 27 has afirst output 29 connected to a control input of thedisarm latch 9 and asecond output 30 connected to a third input of thesound control 10 of thealarm unit 3. - The pulse detector 17 detects each change in the power status of the apparatus 4 between its powered and unpowered states and delivers an output signal on its
output 20 to hold and extendcircuit 21 which is set to an interpretation state if it receives two output signals from the detector 17 within a first pre-determined duration which may be selected to be between 0.1 seconds and 1 hour but is typically of the order of five seconds. The first andsecond latches counter 22 during operation of the device as hereinafter described. - The sequence
correct counter 27 applies a disabling signal on itsoutput 30 to thesound control 10 of thealarm unit 3 when the apparatus 4 is connected to its power source and applies an enabling signal to thesound control 10 onoutput 30 when the apparatus 4 is disconnected from its power source. - The anti-theft device described above with reference to Figure 1 operates so that activation of the
alarm unit 3 occurs in the event that the apparatus 4 is moved whilst the equipment is disconnected from the power supply without the power supply to the apparatus 4 having first been subjected to a coded sequence of on/off states. - Thus, as long as the apparatus 4 is powered, the
output 30 of thecorrect sequence counter 27 disables thesound control 10 of thealarm unit 3 and movement of the apparatus 4, resulting in movement of thetrembler unit 2, does not activate the piezo-electric buzzer 12 of the alarm unit. - If authorised disconnection and movement of the apparatus 4 is required, the apparatus 4 must be first subjected to a coded sequence of connections and disconnections of its power supply in order to render the
disarmed latch 9 operative to disconnect thealarm unit 3 from thetrembler unit 2, since the output signal online 30 from the sequencecorrect counter 27 will enable thesound control 10 of thealarm unit 3 on disconnection of the power from the apparatus 4. - The first step in performing the coded sequence of changes in the power status of the apparatus 4 is to switch the apparatus on and then off within a period of time which does not exceed the first pre-determined duration set by the pulse detector unit 17. This is represented by the
pulse 31 in diagram 3a of Figure 3. Detection ofpulse 31 by hold and extendcircuit 21 at its input causes thecircuit 21 to enter its interpretation state as shown at 32 in diagram 3b of Figure 3. After a pre-determined time delay determined bycircuit 21 and selectable between 0 seconds and 1 hour, thecounter 22 is started by a signal from thecircuit 21 as indicated at 33 in diagram 3c of Figure 3. At the same time, thecounter 22 provides an output online 28 to thesound control 10 of thealarm unit 3 to cause the piezo electric buzzer 12 of the alarm unit to emit timing signals in the form of a regular series of short sounds or beeps as indicated at 35 on diagram 3d of Figure 3. - At a pre-determined time in this series of beeps, corresponding to a second predetermined duration selectable between 1 second and 1 hour and set by the
first latch 24 and ascertained by counting thebeeps 35, the power supply is again switched on as indicated at 36 in diagram 3a of Figure 3. Thecircuit 21 then stops thecounter 22 and the counter then compares the count at this time with the second pre-determined duration set bylatch 24 and, if it corresponds, a first correct sequence pulse is delivered to thecorrect sequence counter 27 onoutput line 26 of thecounter 22 as shown at 37 in diagram 3e of Figure 3. - After a further period corresponding to the delay period of the
circuit 21, thecounter 22 is again started as indicated at 36 in diagram 3c of Figure 3 and the piezo electric buzzer 12 emits a further series ofbeeps 35. After a time corresponding to a pre-determined third duration selectable between 1 second and 1 hour and set by thesecond latch 25, the apparatus 4 is again switched off as indicated at 38 in diagram 3a of Figure 3, thereby stopping thecounter 22 as indicated at 39 in diagram 3c of Figure 3 and stopping the emission of beeps by the piezo electric buzzer 12. If the count in thecounter 22 at this time corresponds to the third pre-determined duration stored inlatch 25, the counter delivers a second correct sequence pulse on itsoutput 26 to thecorrect sequence counter 27 as indicated at 40 in diagram 3e of Figure 3. - Upon receipt of this second
correct sequence pulse 40, thecorrect sequence counter 27 delivers a signal on itsoutput 29 to operate thedisarm latch 9 as indicated at 41 in diagram 3f of Figure 3, so as to prevent output signals from thetrembler unit 2 from reaching the alarm unit and thereby enabling movement of the disconnected apparatus 4 without activation of thealarm unit 3. This alarm disarmed state is preferably indicated by thedevice 1 emitting, for example, five short tones. - When the apparatus 4 is re-connected to the power as indicated at 42 in diagram 3a of Figure 3, the output signal on the
output 29 of thecorrect sequence counter 27 is removed and, as indicated at 43 in diagram 3f, thedisarm latch 9 reverts to its normal condition in which the output of thetrembler circuit 2 is connected to the input of thealarm unit 3. - Should the apparatus 4 be disconnected and moved without first carrying out the above described coded sequence of power connections and disconnections, the
disarm latch 9 will be in its normal condition and thealarm unit 3 will be activated by thetrembler unit 2. When the power to the apparatus 4 is disconnected, the alarm not being disarmed, thedevice 1 will emit, for example, three short tones - an alarm active indication. This warns, for example, a shop assistant that movement of the apparatus 4 in this condition would trigger the trembler to cause an alarm condition. - Although the above described
monitoring device 1 is described as monitoring the voltage on thepower lines - Although the
above device 1 has been described as having itsinputs 1A and 1B connected to the power lines of the apparatus 4, the inputs may be directly or indirectly coupled to the power lines or indeed signal lines of the apparatus 4. - Should the
alarm unit 3 be activated by disconnection of the apparatus 4 from its power source and unauthorised removal of the apparatus 4, the alarm can be simply de-activated merely by re-applying power to the apparatus to the power supply. - Figure 2 shows the
monitoring device 1 embodying the present invention incorporated in another anti-theft device which also includes a tamper system comprising, for example, a light-sensitive resistor 50 provided inside a housing of the device and connected to thedisarm latch 9, so that illumination of theresistor 50, resulting for example from a person tampering with the housing of the device or the equipment in which the device is installed, will cause an output signal to be delivered to thedisarm latch 9 and thereby activate the alarm. A signal applied toinput 51 of thedevice 1 determines whether the device is in a monitoring state to monitor change of the power states of the apparatus 4 or is in a programming state in which selected pre-determined periods and a delay period may be programmed into thelatches circuit 21 via inputs 52-55. A signal applied toinput 56 ofdevice 1 selects whether the presence or absence of voltage or current determines the change of state periods. The tamper system may be provided as a separate unit located externally of the housing of thedevice 1. - This tamper system can be disarmed by entering an appropriately coded sequence through the power lines of the apparatus 4 being monitored. Should the tamper system be activated, the switching of the apparatus 4 being monitored to an on state will not silence the alarm. The internal power source of the
monitoring device 1 must be removed, in this case, to silence the tamper alarm. - The buzzer 12 has two levels of output an attenuated level and an alarmed level. The attenuated level is muted compared to the alarmed level. The attenuated level is used for signalling all beeps, tones and indications. The alarm level is used only when the unit is activated as an alarm.
- It will be appreciated that a monitoring device or anti-theft device embodying the present invention may be incorporated during manufacture into an apparatus to be monitored or may be provided as an attachment thereto.
- The
device 1 is preferably provided with a battery monitor which generates two tones intermittently over a designated period should the internal power supply, thebattery 13, of thedevice 1 fall below a certain level. - When the
device 1 is initially powered up and is not connected to the apparatus 4 being monitored or no signal has yet been received by thedevice 1 from the apparatus 4, then the device is in a so-called 'test' state. This state is terminated when a signal from the apparatus 4 being monitored is first received. - When the
device 1 is in the 'test' state, it generates test tones upon activation of various signals. For example, when the alarm detection circuit is activated (e.g. by triggering the trembler) it generates a series of tones. This series of tones is extended should the tamper system also be activated. - The
device 1 may be placed in a programming state either by initiation by an external trigger or automatically when thedevice 1 is first in the disarmed state. The device has a default code sequence which is accepted as the code for the device. Should the user of the device allow the disarming state to time out (time-out occurring when the device generates the first sequence of tones and the equipment does not change state during this period), then the default code sequence is adopted. - It will be appreciated that a monitoring device embodying the present invention presents the great advantage that it is armed and disarmed merely by connecting and disconnecting its power supply and does not require the use of a separate key switch for arming and disarming the alarm as required by presently available anti-theft devices used to protect such apparatus.
Claims (13)
- A monitoring device (1) for monitoring an apparatus having first and second states, comprising: detecting means (17) for detecting each change of state of the apparatus between its first and second states; timing means (22,23) for measuring the duration between successive changes in the state of the apparatus as detected by the detecting means; memory means (21,24,25) for storing first, second and third pre-determined durations; comparing means (27) for comparing the timing of detected changes in the state of the apparatus and delivering an output signal in the event that first and second changes of state of the apparatus are detected within a duration not exceeding the first pre-determined duration, a third change of state is detected after the second change of state at a time corresponding to the second pre-determined duration and a fourth change of state is detected after the third change of state at a time corresponding to the third pre-determined duration; and means (3) for emitting timing signals during the second and third durations after detecting the second and third changes of state respectively.
- A monitoring device according to Claim 1, wherein the timing means starts to measure each of the durations between the second and third changes of state and the third and fourth changes of state after a pre-determined delay.
- A monitoring device according to Claim 1 or 2, wherein the timing signals are audible signals.
- A monitoring device according to Claim 3, wherein the timing signals comprise a regular series of short sounds or beeps.
- A monitoring device according to any preceding claim, including an alarm unit wherein the output signal of the comparing means disarms the alarm unit.
- A monitoring device according to Claim 5, wherein the alarm unit is disarmed in one of the first and second states of the apparatus and is armed in the other state in the absence of the output signal from the comparing means.
- A monitoring device according to Claim 5 or 6 including a sensor which is operable, upon activation, to supply an alarm signal to the alarm unit to produce a warning signal if the alarm unit is enabled.
- A monitoring device according to Claim 7, wherein the sensor is a trembler unit adapted to supply the alarm signal to the alarm unit upon movement of the trembler unit.
- A monitoring device according to Claim 7 or 8, wherein the warning signal is an audible signal.
- A monitoring device according to any preceding claim, wherein the apparatus is electrically operated apparatus and the first and second states of the apparatus are the power on and power off states of the apparatus.
- A monitoring device according to any preceding claim, wherein the input means comprises a pair of input terminals for coupling to electrical lines of the electrical apparatus to be monitored.
- A monitoring device according to Claim 11, wherein the pair of input terminals are configured to be connected to the apparatus to sense changes in voltage.
- A monitoring device according to Claim 11, wherein the pair of input terminals are configured to be connected to the apparatus to sense changes in current.
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB9503737 | 1995-02-24 | ||
GBGB9503737.0A GB9503737D0 (en) | 1995-02-24 | 1995-02-24 | A monitoring device |
GB9515441 | 1995-07-27 | ||
GB9515441A GB2298304B (en) | 1995-02-24 | 1995-07-27 | A monitoring device |
PCT/GB1996/000196 WO1996026510A1 (en) | 1995-02-24 | 1996-01-30 | A monitoring device |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0811212A1 EP0811212A1 (en) | 1997-12-10 |
EP0811212B1 true EP0811212B1 (en) | 1999-07-21 |
Family
ID=26306578
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP96901078A Expired - Lifetime EP0811212B1 (en) | 1995-02-24 | 1996-01-30 | A monitoring device |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0811212B1 (en) |
AU (1) | AU4494596A (en) |
DE (1) | DE69603354T2 (en) |
WO (1) | WO1996026510A1 (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2959521B2 (en) * | 1997-05-21 | 1999-10-06 | 日本電気株式会社 | Semiconductor device manufacturing method, lead frame |
WO2000026729A1 (en) * | 1998-10-29 | 2000-05-11 | David Paul Viranyi | Alarm for electronic equipment |
US6662023B1 (en) | 2000-07-06 | 2003-12-09 | Nokia Mobile Phones Ltd. | Method and apparatus for controlling and securing mobile phones that are lost, stolen or misused |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4533016A (en) * | 1983-10-14 | 1985-08-06 | Phantom Systems, Inc. | Antitheft ignition system and solenoid apparatus for use therewith |
GB9214600D0 (en) * | 1992-07-09 | 1992-08-19 | Newcom Services Ltd | Alarm circuit |
-
1996
- 1996-01-30 DE DE69603354T patent/DE69603354T2/en not_active Expired - Fee Related
- 1996-01-30 EP EP96901078A patent/EP0811212B1/en not_active Expired - Lifetime
- 1996-01-30 AU AU44945/96A patent/AU4494596A/en not_active Abandoned
- 1996-01-30 WO PCT/GB1996/000196 patent/WO1996026510A1/en active IP Right Grant
Also Published As
Publication number | Publication date |
---|---|
DE69603354D1 (en) | 1999-08-26 |
DE69603354T2 (en) | 2000-01-20 |
AU4494596A (en) | 1996-09-11 |
WO1996026510A1 (en) | 1996-08-29 |
EP0811212A1 (en) | 1997-12-10 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5317304A (en) | Programmable microprocessor based motion-sensitive alarm | |
US5686896A (en) | Low battery report inhibitor for a sensor | |
US5767771A (en) | Electronic equipment theft deterrent system | |
US4942386A (en) | Integrated impact detection and alarm system | |
US4622541A (en) | Intrusion detection system | |
US5686885A (en) | Sensor test method and apparatus | |
US4686514A (en) | Alarm system for computers and the like | |
US5965954A (en) | Anti-theft system for disabling a vehicle engine | |
US6081197A (en) | Fire detector silenceable low battery pre-alarm | |
US4206450A (en) | Fire and intrusion security system | |
CA2304851A1 (en) | Anti-theft system for disabling a vehicle engine | |
US4808972A (en) | Security system with false alarm inhibiting | |
JPH09508979A (en) | Siren device | |
US7046144B2 (en) | Theft deterrent device for appliances | |
US3955183A (en) | Alarm condition sensing and indicating circuit with test capability | |
US5499012A (en) | Intrusion detector test circuit which automatically disables a detected-event indicator | |
WO1994015818A1 (en) | Automotive security system with discrimination between tampering and attack | |
WO1993002897A1 (en) | Vehicle security system | |
EP0811212B1 (en) | A monitoring device | |
US4103285A (en) | Vehicle anti-theft alarm system | |
US5087908A (en) | Portable alarm system with automatic operating state transferral | |
GB2298304A (en) | Theft alarm device | |
US5528085A (en) | Anti-theft device for vehicle using interrupt relays and diodes | |
WO1995021077A1 (en) | Deactivation device | |
ITMI972210A1 (en) | VEHICLE BURGLAR ALARM SYSTEM |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 19970704 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): DE ES FR IE IT NL SE |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
17Q | First examination report despatched |
Effective date: 19980724 |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): DE ES FR IE IT NL SE |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY Effective date: 19990721 Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 19990721 Ref country code: IT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRE;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.SCRIBED TIME-LIMIT Effective date: 19990721 Ref country code: ES Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY Effective date: 19990721 |
|
REF | Corresponds to: |
Ref document number: 69603354 Country of ref document: DE Date of ref document: 19990826 |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |
|
ET | Fr: translation filed | ||
NLV1 | Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act | ||
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: IE Payment date: 20000131 Year of fee payment: 5 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20010122 Year of fee payment: 6 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20010125 Year of fee payment: 6 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20010130 |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: MM4A |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20020801 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20020930 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |