GB2472982A

GB2472982A - Portable apparatus dispensing a marker liquid

Info

Publication number: GB2472982A
Application number: GB0914724A
Authority: GB
Inventors: Simon Nicholas Thelwell; Tudor Gwyn Jones
Original assignee: S & T Systems Ltd
Current assignee: S & T Systems Ltd
Priority date: 2009-08-24
Filing date: 2009-08-24
Publication date: 2011-03-02
Anticipated expiration: 2029-08-24
Also published as: GB0914724D0; GB2472982B

Abstract

A portable apparatus is provided dispensing a marker liquid which may include synthetic DNA or a fluorescent die. The apparatus comprises a vessel 42 containing a liquid and a dispenser 44 that can be triggered to dispense liquid from the vessel as a projected spray or jet. A control system 32 can activate the dispenser 44 and includes a proximity detector 22 for detecting a person near to the apparatus. The control system 32 has a disarmed and an armed state, and switching means operative to set the state of the control system. In the armed state, the dispenser is triggered in the event that the proximity detector 22 detects a person near the apparatus. The switching means may be operated by remote control or may operate automatically in response to the sound produced by breaking glass. The control system 32 may be in an on or off state. In the off state, the control system 32 is inhibited from becoming armed. The control system 32 may change from the off state to the on state when the apparatus is mounted on a bracket 50. The portable apparatus is particularly suited for use during the collection of cash from a bank by a courier.

Description

Apparatus for dispensing a marker liquid This invention relates to apparatus for dispensing a marker liquid. Particularly, but not exclusively, it relates to apparatus for dispensing a liquid that can mark a person or an object in a manner that can be detected by subsequent forensic examination.

In GB-A-2 319 337 there is disclosed a liquid composition for applying to objects or to a person as a tracer or identifier. GB-A-2 385 853 extends this by providing a means by which a unique DNA sequence can be created. This sequence can be incorporated within the composition of GB-A-2 319 337 to produce a marker that can be virtually guaranteed to be unique and which can subsequently be positively identified.

Detection of such marker compositions upon a person can be used to imply that the person has been in a particular place or in contact with particular goods. This can be done with sufficient certainty to be used as evidence in court proceedings.

It is known to provide installations that will dispense a marker liquid upon activation of an intruder alarm whereby goods protected by the alarm, the person who triggered the alarm (or both) are marked by the marker liquid. Making the existence of such installations clearly apparent, for example using warning notices, has been found to act as a strong deterrent to theft. However, such installations are costly, and this inhibits their use in situations where the risk of theft is transient -for example, in places where deliveries or collections of cash or valuables are made from time to time.

An aim of this invention is to provide apparatus for dispensing a marker liquid that is portable and that can be deployed as and when required to offer protection to people, goods or cash during particular, temporary circumstances in which an attack is considered to be likely.

To this end, this invention provides apparatus for dispensing a liquid comprising: a vessel for containing a liquid to be dispensed, a dispenser that can be triggered to dispense liquid from the vessel and to project it; a control system for activation of the dispenser, the control system including a detector that can detect the proximity of a person to the apparatus, the control system having a "disarmed" and an "armed" state; and switching means operative to set the control system to its armed or to its disarmed state: wherein, in the armed state, the control system is operative to trigger the dispenser in the event that the detector detects the proximity of a person to the apparatus.

During normal use, the apparatus is maintained in the disarmed state. However, when an operator believes that an attack is imminent or is taking place, he or she operates the switching means to cause the apparatus to switch to the armed state, so that it causes the liquid to be sprayed froiii the apparatus wheii a persoii has entered a field of detectioii of the detector.

Advantageously, the switching means is operative to change the state of the control system without requiring the user to make direct contact with the apparatus. For example, the switching means may be operable by an operator using a remote control unit, such as an infra-red or radio-frequency remote control. Alternatively or additionally, the switching means may operate automatically in response to specific circumstances. For example, it may be responsive to sound such as that produces by breaking glass.

The control system may also be in an "on" or an "off' state. In the "off' state, the control means is inhibited from becoming armed. This reduces the chance of arming taking place at an inappropriate time. The control system may be configured to change from the "off' to the "on" state automatically. For example, the control system may become "on" when the apparatus is mounted on a bracket or other support for use, and become "off' when it is removed from the support for moving to another site. Alternatively or additionally, the control system may be configured to change from the "off' to the "on" state in response to the state of a manually-operated control, such as a keyswitch.

The dispenser may be integral with the vessel, whereby the vessel, dispenser and liquid can be installed in the unit as a single unit, pre-filled with the marker liquid. For example, the dispenser may include a gas producer within the vessel that can be activated by application of an electric signal to an electrical terminal of the dispenser. Activation of the dispenser may cause the liquid to be driven from the vessel through a dispensing tube. In these embodiments, the dispensing tube is typically connected to a nozzle from which the liquid can be dispensed as a jet or as a spray.

The liquid in the vessel typically includes a marker that can be identified. For example, the marker may include synthetic DNA (for example, as described in the published patent applications identified above). In this case, it is possible to associate synthetic DNA discovered on a person with a particular source in a manner that can be introduced as legal evidence.

The liquid may further include a fluorescent dye. This can help locate the parts of a person or article that have been marked with the marker liquid.

An embodiment of the invention will now be described in detail, by way of example, with reference to the accollipanying drawings, in which: Figures 1 and 2 are diagrammatic front and side views of dispensing apparatus embodying the invention; and Figure 3 is an exploded schematic view of the embodiment of Figures 1 and 2.

With reference to Figures 1 and 2, dispensing apparatus embodying the invention comprises a unit that is housed in a metal case 10 that is of size and shape that can be readily carried. The case is shaped as a cuboid, with front, rear, side bottom and top walls. A carrying handle 12 is secured to the top wall to enable an operator to readily carry the unit to a place where it is to be used.

On the front panel there is carried a liquid dispensing nozzle 20, a passive infra-red proximity sensor 22 and an optional status LED 24. The sensor 22 has an output that changes state when a person enters within a field of sensitivity of the sensor. A charging connector 30 is mounted on the top panel, so that it can be accessed when several of the units are positioned close together on a flat surface. An external battery charge indicator may also be provided.

Within the case 10, as shown in Figure 3, the unit further comprises a control module 32 that controls aspects of operation of the unit. Rechargeable cells 34 within the case 10 provide electrical power to the control module 32 all other electrical components of the unit. A radio frequency (RF) receiver 36 is provided within the case 10, optionally with an external antenna 38. An output of the RF receiver 36 is connected to the control module 32. The RF receiver applies a signal to that output in the event that it receives an RF signal from an associated RF transmitter, which, in this case, is a small, portable device. The RF receiver and transmitter are coded to one another to prevent accidental arming or disarming. (Infra-red remote control could be used instead, but has the disadvantage of requiring a clear line-of-sight between the transmitter and the receiver.) One or more magnetically operated switches 40 are located within the case close to one or more of the side walls and the rear wall of the case 10, and are connected to the control module 32. The output of the sensor 22 is also connected to the control module 32.

A vessel 42 that contains a volume of a marker liquid is contained within the case 10. In this embodiment, the iiiarker liquid contains au ultra-violet fluorescent dye that is invisible in normal light and a quantity of synthetic DNA. The vessel carries a dispenser 44 that can be triggered by an electrical signal. Upon receiving such a signal, the dispenser 44 activates a charge that causes gas to be evolved within the vessel 42. The consequent increase of pressure within the vessel 42 causes the marker liquid to be driven from it into a delivery tube, and then to the nozzle 20 from which it is delivered in a spray of small liquid droplets. The vessel 42 and dispenser 44 may be obtained as a unit, pre-filled with the marker liquid. This can be replaced readily in the event that the unit is triggered and the liquid dispensed.

It should be understood that the layout shown in Figure 3 is entirely diagrammatic, and does not represent the actual disposition of components within the case 10. This will vary significantly from one embodiment to another.

The case 10 of this embodiment is used in association with a bracket 50 that is permanently located at a site that is to be protected. The bracket 50 will typically be secured to a wall or door frame at around head height. The bracket 50 provides a platform upon which the unit can be placed to direct its sensor 22 and nozzle 20 into a pathway that is likely to be followed by an attacker making an entrance or an escape. The bracket 50 has magnets that can hold the case 10 in place on the bracket, and allow its ready removal when it is no longer required.

When the unit is mounted on the bracket 50, the magnetic switch 40 detects the presence of the magnets. (As a potentially less-costly alternative to magnetic switches, one or more mechanically operated switch may be used which are activated when the case 10 is mounted on the bracket 50. However, this will typically require an aperture in the case for an actuator of each switch, which may be considered to be disadvantageous.) Operation of the unit will now be described.

When the unit is free-standing, remote from the bracket 50, the magnetic switches 40 isolate power from the other components of the unit, thereby placing the unit in an "off" state.

Once the unit has been mounted on a bracket 50, the state of at least one of the magnetic switches 40 changes, and the unit enters an "on" state. This applies power to the control module 32. The unit then enters a "disarmed" state, in which the control module 32 monitors the output of the RF receiver 36. In the large majority of cases, the next event will be that the unit is removed from the bracket 50, the magnetic switches revert, and the unit is returned to the "off' state.

If, while the unit is on and disarmed, an operator determines that an attack is in progress, then he or she activates the associated RE transmitter, which causes the RF receiver 36 to send a signal to the control module 32. The control module 32 then causes the unit to enter an "armed" state, in which it monitors the output from the sensor 22. In the armed state, in the event that the control module 22 detects a signal on the output from the sensor 22 to indicate that a person has entered it field of sensitivity, the control module 32 sends a triggering electrical signal to the dispenser 44, thereby causing the marker liquid to be ejected from the nozzle 20 to be deposited upon the person that was detected by the sensor 22. Depending upon the application of the unit, the dispenser 44 may be configured to dispense all of the liquid at once when first triggered, or in multiple shots in response to multiple signals received from the sensor 22 as several people pass into its field of sensitivity.

The control module 32 operates the status LED 24 to give a visual indication of the state of the unit. The LED 24 will be extinguished when the unit is off, green when on but disarmed, and red when armed.

It must be understood that this embodiment has three distinct states of operation. These will be described with reference to a typical instance of use of the unit: during collection of cash from a bank by couriers.

It can be "off' in order to completely inhibit discharge of the marking liquid. This prevents accidental (and potentially hazardous) discharge as might, for example, happen were the RF transmitter to be accidentally operated while the unit is being transported to the place from which cash will be collected.

During its normal use, it is positioned to be capable of dispensing its marker liquid. For example, this may be on a bracket secured to a wall of a bank entrance hallway. It is then "on" but "disarmed". In this state, the liquid will not be dispensed even if the sensor 22 is triggered, so allowing legitimate customers to pass into and out of the bank. In most cases, the unit will simply be removed from the bracket once the collection is complete, and so return to the "off' state.

If, during collection of the cash, a courier realises that he or she, the bank or its personnel are under attack, the courier will trigger their RF transmitter, so placing the unit in the armed state. If this can be done before the attackers enter the bank, activation of the unit and marking of the attackers may act as a sufficient deterrent to cause the attack to be aborted.

Otherwise, the attackers will be marked as they attempt to leave the bank.

Since the unit is intended to be armed only in the event of an attack taking place, in this embodiment arming is irreversible. This is to prevent a courier being forced, under duress from an attacker, to disarm the unit. An alternative is to allow the unit to be disarmed only under specific circumstances -for example, after a predetermined delay has passed. The particular arrangement adopted will depend upon the particular circumstances in which the unit is to be used and the the preferences of the user.

The unit may have alternative configurations to suit various intended purposes. For example, when it is to be used in an occasional or one-off place, it may not be possible or practical to install a bracket 50. In that case, a unit can include a manual on-off switch (such as a keyswitch) either as an alternative to or an addition to the magnetic switches 40.

The means of arming may also very from one application to another. The unit may be configured to arm itself automatically on the occurrence of a particular event. One arrangement to achieve this is to provide the unit with an acoustic glass-break detector. An example use of such a unit is to protect a shop window or a display case, for example while a shop is closed. In such cases, the unit is placed in a space to be protected and manually switched on. It then remains unarmed, and will normally be subsequently retrieved and switched off. However, if the space is attacked with the result that the window or display case is broken, the glass-break detector will arm the unit, with dispersions of the liquid being triggered immediately upon the detector 20 detecting a person in its field of sensitivity.

After use, the unit may be connected through the charging connector 30 to an external power supply to re-charge the rechargeable cells 34.

The control module may also be operable in a test mode. In the test mode, the unit can be in the "off', "on", "disarmed", "armed" and "triggered" states as described above. However, instead of triggering the dispenser, the triggering signal is sent to a sounder. In this way, the unit can be tested without dispensing the liquid -operation of the sounder iiidicatiiig that, in actual operation, the liquid would be dispensed.

Claims

Claims 1. Apparatus for dispensing a liquid comprising: a vessel for containing a liquid to be dispensed, a dispenser that can be triggered to dispense liquid from the vessel and to project it; a control system for activation of the dispenser, the control system including a detector that can detect the proximity of a person to the apparatus, the control system having a "disarmed" and an "armed" state; and switching means operative to set the control system to its armed or to its disarmed state: wherein, in the armed state, the control system is operative to trigger the dispenser in the event that the detector detects the proximity of a person to the apparatus.
2. Apparatus according to claim 1 in which the switching means is operative to change the state of the control system without requiring the user to make direct contact with the apparatus.
3. Apparatus according to claim 2 in which the switching means can be operated by an operator using a remote control unit.
4. Apparatus according to claim 1 or claim 2 in which the switching means operates automatically in response to specific circumstances.
5. Apparatus according to claim 4 in which the switching means can responsive to sound such as that produces by breaking glass.
6. Apparatus according to any preceding claim in which the control system may be in an "on" or an "off" state.
7. Apparatus according to claim 6 iu which in the "off' state, the control means is inhibited from becoming armed.
8. Apparatus according to claim 6 or claim 7 in which the control system is configured to change from the "off' to the "on" state automatically.
9. Apparatus according to claim 8 in which the control system changes from the "off' to the "on" state when the apparatus is mounted on a bracket or other support for use, and become "off' when it is removed from the support.
10. Apparatus according to claim 6 or claim 7 in which the control system is configured to change from the "off' to the "on" state in response to the state of a manually-operated control.
11. Apparatus according to any preceding claim in which the dispenser is integral with the vessel.
12. Apparatus according to claim 11 in which the dispenser includes a gas producer within the vessel that can be activated by application of an electric signal to an external electrical terminal of the dispenser.
13. Apparatus according to claim 11 or claim 12 in which activation of the dispenser causes the liquid to be driven from the vessel through a dispensing tube.
14. Apparatus according to claim 13 in which the dispensing tube is typically connected to a nozzle from which the liquid can be dispensed as a jet or as a spray.
15. Apparatus according to any preceding claim in which the liquid includes a marker that can be identified.
16. Apparatus according to claim 13 in which the liquid in the vessel includes synthetic DNA.
17. Apparatus according to any preceding claim in which the liquid includes a fluorescent dye.
18. Apparatus for dispensing a liquid substantially as described herein with reference to the accompanying drawings.