GB2315683A

GB2315683A - Device for vaporising fluids

Info

Publication number: GB2315683A
Application number: GB9616118A
Authority: GB
Inventors: Graham Nole Slee; Barrie Peary
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-07-31
Filing date: 1996-07-31
Publication date: 1998-02-11
Anticipated expiration: 2016-07-31
Also published as: GB9616118D0; GB2315683B

Abstract

A device for vaporising a fluid comprising a heat generation means arranged to heat a heating element (1), the heating element (1) being connectable to a fluid supply (18), wherein the heat generation means is adapted to provide heat substantially instantaneously to the heating element (1), vapour thereby being produced substantially instantaneously.

Description

Device for Vaporising Fluids Field of the Invention This application relates to machines for vaporising fluids, and in particular to a battery operated device for vaporising fluids.

Background Devices for vaporising fluids are known, and are used in many different applications. For example, electrically operated smoke making machines using a non-toxic fluid, the vapour of which appears as smoke are known, and are used for applications including security (to screen out goods and valuables from the intruder's sight), entertainment (to create mood lighting effects and to reinforce laser lighting displays), and as a training aid for the emergency services and security forces. This type of smoke machine produces smoke by passing fluid into metal tubing encapsulated in a metal block, which is in turn heated by an element. Vapour, in the form of smoke, emerges from the open end of the tube, the fluid having been heated sufficiently in the tube to cause vaporisation thereof. The fluid is forced through the tubing by a pump.

A disadvantage of this type of device is that a considerable amount of energy is wasted in heating up the block. Also, the block must be heated all the time the machine is on standby (waiting until smoke production is required). Machines specified for security use are left powered-up all the time. This is wasteful both of energy and money.

The power requirement of such machines necessitates the use of mains electricity. This is a disadvantage in that the machines are not portable, and will fail during a power cut, which is undesirable when used in security applications.

Machines which are used for vehicle security are however, powered by the vehicle's battery and this power is applied constantly to maintain the heat of the block. Out of necessity, to conserve the vehicle's battery, they are low powered. Due to the resulting discharge of the vehicle's battery, a separate battery is required to operate the circuitry and the pump of the smoke machine. Another failing with this type of vehicle security smoke machine is that most existing alarms will fail to operate properly with them, due to current being the rmo static ally switched into the machine's heating element, while on standby, triggering the voltage drop detection circuit of the alarm and thus falsely sounding the alarm.

It would therefore be advantageous to provide a device for vaporising a fluid in which the heating device does not need to receive power constantly.

Summary of the Invention The invention provides a device for vaporising a fluid comprising a heat generation means arranged to heat a heating element, the heating element being connectable to a fluid supply, wherein the heat generation means is adapted to provide heat substantially instantaneously to the heating element, vapour thereby being produced substantially instantaneously.

Preferably the heating element is a tube through which the fluid is passed. More preferably, one end of the tube is connectable to a fluid supply, which is suitably a reservoir. Even more preferably, a pump is provided to pump the fluid to the heating element. Advantageously the pump is provided with a primer, and the primer is preferably located between the reservoir and the pump. The heating element may be wound into a coil, and may be made from steel, copper or an alloy material. Where the heating element is made from steel, the steel is preferably stainless.

The heat generation means suitably comprises a power supply which is connected to the heating element, and arranged to provide an electric current through the heating element, the electric current being sufficient to heat the heating element to a temperature whereby fluid passing therethrough is substantially vaporised. The power supply is advantageously provided by a battery, and the battery is suitably rechargeable. The battery may be a rechargeable lead-acid battery.

In one embodiment of the invention, the battery is connected to a charger, and the charger is preferably connected to a mains electricity supply.

Control means may be provided to regulate the heat generation means. Preferably, the control means ensures that the heating element runs at a substantially constant temperature.

Preferably, the control means includes an infra-red detector to detect the amount of infra-red radiation given off by the heating element, and more preferably a comparator is provided to compare the output of the detector with a reference value. Even more preferably, when the reference value is exceeded by the output of the detector, the output from the heat ing element is reduced. A switch, preferably a solenoid switch, is provided between the power supply and the heating element, and the said switch is preferably actuated in accordance with the output of the comparator, allowing a current to flow when the output from the infra-red detector is below the reference value, and preventing the flow of current when the output from the infra-red detector exceeds the reference value.

The control means may further include a power supply monitor which prevents a current from flowing to the heating element if the power supply cannot provide sufficient power to heat the heating element to a degree which vaporises fluid passing therethrough. The power supply monitor is particularly useful where the power supply is a battery. Advantageously, the power supply monitor may further include a timer which allows current to flow to the heating element after a pre-set period of time has elapsed, thereby allowing the battery to recover.

In one embodiment of the invention, the control means also includes a checker which checks that a current is supplied to the heating element.

Preferably, the output of the checker controls the pump, allowing the pump to be activated if the checker has established that a current is being supplied to the heating element, and de-activating the pump when insufficient current is being supplied to the heating element. The control means may also include a timer or delay unit, to delay activation of the pump after detection of a current being supplied to the heating element. This has the effect of allowing the heating element to heat up to its working temperature prior to fluid being passed therethrough by the pump. Advantageously, if the checker detects a fall in the current supplied to the heat ing element, the timer or delay unit does not de-activate the pump unless the fall in current supplied continues for more than a predetermined time period.

In another embodiment of the invention, the switch is a mosfet. A cooling device may be provided to cool the mosfet, and the cooling device may be in the form of a heat sink and/or fan. The mosfet may also be connected to a thermal switch which turns off power to the mosfet.

The fluid used in the device is preferably non-toxic, and even more preferably is scented. The fluid may have the appearance of smoke when vaporised. Scenting the fluid has numerous advantages. First it is desirable to scent to fluid so that fire officers will be able to immediately establish that the smoke in a smoke filled space does or does not result from a fire. Secondly, it may be desirable to scent the fluid so that the vapour has a pungent odour. Thirdly, by scenting the fluid, the garments of anyone coming into contact with the vapour will smell, thereby facilitating the identification of such persons.

The fluid used in the device may comprise an incapacitant capable of incapacitating persons in a vapour filled space.

The device for vaporising a fluid may be connected to a burglar alarm, the device for vaporising a fluid being activated when the burglar alarm is activated.

According to another aspect of the invention, the device for vaporising a fluid forms part of a vehicle security system, the battery and charging system of the vehicle providing the electricity supply. The device may be activated by the sound of the alarm.

The invention provides a particularly efficient device for producing vapour, which only requires power when vapour is required, and therefore is energy efficient. The device is considerably cheaper to manufacture than known devices. The power requirement is such that the device can be used as part of a vehicle security system, relying for power on the vehicle's battery and charging system.

The device is self-contained, compact and light weight which means that the device is easily portable. These features make the device particularly useful for security forces and the emergency services as training aids, and for producing special effects in discos, theatres, filming, etc..

It is particularly useful to be able to use the device in conjunction with a burglar alarm. By filling a room with smoke, it is almost impossible for an intruder to find his way out of the room. This means that the police have time to arrive at the scene of the burglary, and can wait for the smoke to clear before capturing the intruder.

Determined thieves often disconnect the electricity supply to the building which they intend to break into. This renders many alarm systems and smoke generating devices useless. Smoke generating devices of the prior art require large battery packs and expensive inverters to be operable in the event of mains failure. The device of the invention does not suffer from these disadvantages.

When used as part of a vehicle security system, when the device is activated the vehicle is filled with smoke, inhibiting the intruder's vision, and thereby preventing him from driving the vehicle away. Also, the device drains the vehicle's battery. This means that if a thief decides to wait until the smoke has cleared, he will still not be able to take the vehicle away, as there will be insufficient energy in the battery to start the engine. However, over a longer period of time the battery will recover, so that when the owner returns to the vehicle some hours later, he will be able to start the engine.

Brief Description of the Figures Figure 1 is a circuit diagram of the first embodiment of the invention; Figure 2 is a circuit diagram of the second embodiment of the invention; Figure 3 shows a switch connected to the control port of the first or second embodiment of the invention; Figure 4 shows the control port of the first or second embodiment of the invention connected to a burglar alarm; and Figure 5 is a circuit diagram of an interface which enables the first or second embodiment of the invention to be operatively connected to a vehicle security system.

Detailed Description of the Preferred Embodiments In the preferred embodiments of the invention, the devices for vaporising a fluid are described with reference to smoke making machines.

The first and second embodiments of the invention provide instantaneous battery operated smoke making machines for general purpose use, for example; in special effects and for emergency services and security forces training exercises.

The third and fourth embodiments of the invention provide instantaneous battery operated smoke machines for use as accessories to an existing burglar alarm systems, and are employed to cut-off the field of vision of an intruder.

The fifth and sixth embodiments of the invention provide instantaneous battery operated smoke machines for use as accessories to a vehicle security alarm systems, and are employed to cut-off the field of vision of an intruder.

The first embodiment of the present invention is shown in Figure 1, and comprises a heating element 1, infra-red detectors 2, a comparator 3, a reference 4, gates 5, 12 & 13, drivers 6 & 14, a resistor 7, a capacitor 8, a solenoid switch 9, a checker 10, timer 11, pump controller 15, pump 16, primer 17, reservoir 18, power supply unit (PSU) 19, relay 20, battery monitor 21, battery 22, charger 23, and a control port 24. Many of these items are contained on a circuit board 29. Switch 30 and link 37, shown in Figure 3, are provided to enable the device to be turned on and off.

Prior to use, a smoke fluid is poured into the reservoir 18 and the primer 17 is operated to prime the pump 16 with smoke fluid.

The device is switched on via port 24. Upon switch-on from cold, the infra-red output from heating element 1 is very low, and therefore the voltage output from the infra-red detectors 2 received by the comparator 3 is higher than reference voltage 4, thus the output from comparator 3 to gate 5 is high, and the driver 6 energises the solenoid switch 9 via resistor 7 and capacitor 8. Hence power is supplied to heating element 1 which heats-up rapidly.

The conditions for the heating element 1 to heat up rapidly, such as voltage being present at, and current flowing through heating element 1, are checked by a checker 10 which passes the supply voltage to a timer 11, which is voltage dependant. This then delays the pump 16 slightly, according to the state of the battery 22 and to allow the heating element 1 to reach its operating temperature. Timer 11 is connected to delay gate 12 which is connected to the output of the pump controller 15 and gate 13.

Gate 13 is in turn connected to driver 14 which supplies power to the pump 16 when all the pre-set conditions are met.

Smoke fluid contained in the reservoir 18 is pulled through the primer 17 and pumped into the heating element 1 in which it is vaporised, emerging under force as smoke from the open end of the element 1.

The cooling effect of the smoke fluid passing into heating element 1 generally stabilises the temperature of heating element 1. However, local overheating of heating element 1 can occur. Infra-red detectors 2 detect any increase in the output of infra-red radiation from the heating element.

When an increase is detected, the voltage to the comparator 3 drops below the reference value 4, turning off its output and, via gate 5, disabling the driver 6, in turn de-energising the solenoid switch 9 which turns off power to heating element 1.

Under normal operating conditions the heating element 1 is only off for a fraction of a second. Timer 11 ignores the checker 10 when it indicates loss of voltage and current signals for such short intervals. However, if heating element 1 is off for a long time this signifies a fault, and the timer 11 disables gate 12 removing pump control, hence disabling the pump 16.

To stop the coil of the solenoid switch 9 overheating, a resistor 7 may be included in series with its supply from the driver 6. A capacitor 8 may be included across the resistor 7 to provide a switch-on pulse.

If the battery 22 is discharged to below a predetermined safe working voltage, battery monitor 21 disables the pump 16 and de-energises the solenoid switch 9 via gates 13 & 15 respectively. This protects against damage to the battery 22 and from unvaporised smoke fluid being pumped out of the heating element 1. The battery monitor 21 has a built in timer which resets its output, bringing the solenoid switch 9 and pump 16 back on after an interval, provided the battery 22 has recovered its charge.

The battery 22 is charged by a charger 23, whose power is derived from a suitable supply such as mains electricity.

The smoke making machine is switched on by a switch 30 (see Figure 3) which is connected to the control port 24, and which energises the relay 20, switching on power from the power supply unit (PSU) 19. A link 37 connects the other side of the relay to ground.

The second embodiment of the present invention is shown in Figure 2, and comprises a heating element 1, infra-red detectors 2, a comparator 3, a reference voltage 4, gates 5, 12 & 13, drivers 6 & 14, a mosfet 25, heat sink 26, thermal switch 27, fan 28, a checker 10, timer 11, pump controller 15, pump 16, primer 17, reservoir 18, power supply unit (PSU) 19, relay 20, battery monitor 21, battery 22, charger 23, and a control port 24.

Many of these items are contained on a circuit board 29. Switch 30 and link 37, shown in Figure 3, are provided to enable the device to be turned on and off.

Prior to use a smoke fluid is poured into the reservoir 18 and the primer 17 is operated to prime the pump 16 with smoke fluid.

The device is switched on via port 24. Upon switch on from cold, the infra-red output from the element 1 is very low, and therefore the voltage output of the infra-red detectors 2 to the comparator 3 is higher than the reference voltage 4, and thus the comparator 3 output to gate 5 is high and driver 6 turns on the mosfet 25. Hence power is supplied to heating element 1 which heats up rapidly.

The conditions for the element 1 to heat up rapidly, such as voltage being present at, and current flowing through heating element 1, are checked by a checker 10 which passes the supply voltage to the timer 11, which is voltage dependant. This then delays the pump 16 slightly, according to the state of the battery 22, allowing the element 1 to reach its operating temperature. Timer 11 is connected to delay gate 12 which is connected to the output of the pump controller 15 and gate 13. Gate 13 is in turn connected to driver 14 which supplies power to the pump 16.

Smoke fluid contained in the reservoir 18 is pulled through the primer 17 and pumped into the heating element 1 in which it is vaporised, emerging under force as smoke from the open end of heating element 1.

The cooling effect of the smoke fluid passing into heating element 1 generally stabilises the temperature of heating element 1. However, local overheating of heating element 1 can occur. Infra-red detectors 2 detect any increase in the output of infra-red radiation from the heating element 1. When an increase is detected, the voltage to the comparator 3 drops below the reference value 4, turning off its output and, via gate 5 and the thermal switch 27 disables the driver 6, turning-off the mosfet 25 which turns-off power to the heating element 1.

Under normal operating conditions the heating element 1 is only off for a fraction of a second. Timer 11 ignores the checker 10 when it indicates loss of voltage and current signals for such short intervals. However, if heating element 1 is off for a longer time this signifies a fault, and the timer 11 disables gate 12 removing pump control, hence disabling the pump 16.

The mosfet 25 is connected to a heat sink 26, since it has to dissipate a lot of power in heat. Heat sink 26 is cooled by a fan 28. In the event of fan 28 failing, the mosfet 25 and heat sink 26, will get very hot, which could cause the mosfet 25 to fail. To avoid this the thermal switch 27 opens, disconnecting the signal from the driver which turns-off the mosfet and hence the heating element 1.

If the battery 22 is discharged to below a predetermined safe working voltage, the battery monitor 21 disables the pump 16 and turns-off the mosfet 25 via driver 6, via gates 13 & 15 respectively. This is to protect against damage to the battery 22 and from unvaporised smoke fluid being pumped out of the heating element 1. The battery monitor 21 has a built in timer which resets its output, bringing the mosfet 25 and pump 16 back on after an interval, provided the battery 22 has recovered its charge.

The smoke making machine is switched on using the switch 30 (see Figure 3) which is connected to control port 24, and which energises the relay 20 switching on power from the power supply unit (PSU) 19. A link 37 connects the other side of the relay to ground.

The third embodiment of the invention comprises and operates as the first embodiment of the invention and an existing burglar alarm, the control panel 38 being connected to the control port 24, as shown in Figure 4. In common with the vast majority of burglar alarm panels, the bell (or siren) output goes negative with respect to the 12 Volt supply in an alarm condition, thus 12 Volts are applied across terminals B and C of the control port 24 which is connected to the relay 20 of Figure 1, hence switching-on the smoke machine. Smoke is produced, cutting off the field of vision of the intruder while the burglar alarm bell or siren is sounding, unless the battery 22 becomes too discharged and the battery monitor 21 shuts the machine down.

The fourth embodiment of the invention comprises and operates as the second embodiment of the invention and an existing burglar alarm, the control panel 38 being connected to the control port 24, as shown in Figure 4. In common with the vast majority of burglar alarm panels, the bell (or siren) output goes negative with respect to the 12 Volt supply in an alarm condition, thus 12 Volts are applied across terminals B and C of the control port 24 which is connected to the relay 20 of Figure 2, hence switching-on the smoke machine. Smoke is produced, cutting-off the field of vision of the intruder while the burglar alarm bell or siren is sounding, unless the battery 22 becomes too discharged and the battery monitor 21 shuts the machine down.

The fifth embodiment of the invention comprises and operates as the first embodiment of the invention, the smoke produced being used to fill the vehicle, thereby cutting off the vision of an intruder. Battery 22 and charger 23 (Figure 1) are replaced by the battery and charging system of the vehicle being employed as the power source for the device. It also comprises an inverter 34 a transducer 31, an amplifier 32, a rectifier 33, a gate 35, a driver 36 and a link 37, connected to the control port 24, shown in Figure 5. The items shown in Figure 5 serve to interface the present invention with the vehicle's security alarm siren. On removal of the vehicle's ignition key, the vehicle's accessory circuit is switched-off and assumes a logic 0 state. Inverter 34 converts this into a logic 1 output.

Should the vehicle's alarm siren sound, the transducer 31 picks up the sound, turning it into an electrical signal. This is amplified by the amplifier 32, and the signal is rectified into a logic 1 output by the rectifier 33.

The output of the inverter 34 and the output of the rectifier 33 form the two inputs of gate 35, which has an AND function. Thus when both inputs are logic 1, the output will also be logic 1, causing the driver 36 to conduct via control port 24 and hence the relay 20 (fig. 1) is energised, switchingon the smoke machine. The return to the positive supply from the relay 20 is via the link 37. Should the alarm siren sound, or the transducer pick up an extremely loud noise when the vehicle is in use, the output of the AND gate will be inhibited because the accessory circuit will be live (logic 1), and hence the vehicle's driver is protected from smoke cutting-off his vision.

The sixth embodiment of the invention comprises and operates as the second embodiment of the invention, the smoke produced being used to fill the vehicle, thereby cutting off the vision of an intruder. Battery 22 and charger 23 (Figure 2) are replaced by the battery and charging system of the vehicle being employed as the power source for the device. The sixth embodiment also comprises an inverter 34 a transducer 31, an amplifier 32, a rectifier 33, a gate 35, a driver 36 and a link 37 connected to the control port 24, as shown in Figure 5. The items shown in Figure 5 serve to interface the present invention with the vehicle's security alarm siren. On removal of the vehicle's ignition key, the vehicle's accessory circuit is switched off and assumes a logic 0 state. Inverter 34 converts this into a logic 1 output. Should the vehicle's alarm siren sound, the transducer 31 picks up the sound, turning it into an electrical signal, this is amplified by the amplifier 32, and the signal is rectified into a logic 1 output by the rectifier 33. The output of the inverter 34 and the output of the rectifier 33 form the two inputs of the gate 35, which has an AND function. Thus when both inputs are logic 1, the output will also be logic 1, causing the driver 36 to conduct via control port 24 and hence the relay 20 (fig. 2) is energised, switching-on the smoke machine. The return to the positive supply from the relay 20 is via the link 37. Should the alarm siren sound, or the transducer pick-up an extremely loud noise when the vehicle is in use, the output of the AND gate will be inhibited because the accessory circuit will be live aogic 1), and hence the vehicle's driver is protected from smoke cutting-off his vision.

Claims

1) A device for vaporising a fluid comprising a heat generation means arranged to heat a heating element, the heating element being connectable to a fluid supply, wherein the heat generation means is adapted to provide heat substantially instantaneously to the heating element, vapour thereby being produced substantially instantaneously.

2) A device according to Claim 1, wherein the heating element is a tube through which the fluid is passed.

3) A device according to Claim 2, wherein one end of the tube is connectable to a fluid supply.

4) A device according to any preceding claim, wherein the fluid supply is a reservoir.

5) A device according to any preceding claim, wherein a pump is provided to pump the fluid to the heating element.

6) A device according to Claim 5, further comprising a primer arranged to prime the pump.

7) A device according to any preceding claim, wherein the heating element is wound into a coil.

8) A device according to any preceding claim, wherein the heating element comprises steel, stainless steel, copper or an alloy material.

9) A device according to any preceding claim, wherein the heat generation means comprises an power supply which is connected to the heat ing element, and arranged to provide an electric current through the heating element, the electric current being sufficient to heat the heating element to a temperature whereby fluid passing therethrough is substantially vaporised.

10) A device according to Claim 9, wherein the power supply is provided by a battery.

11) A device according to Claim 10, wherein the battery is rechargeable.

12) A device according to Claim 11, wherein the battery is a rechargeable lead-acid battery.

13) A device according to any of claims 10 to 12, wherein the battery is connected to a charger.

14) A device according to Claim 13, wherein the charger is connected to a mains electricity supply.

15) A device according to any preceding claim, further comprising control means to regulate the temperature of the heating element.

16) A device according to Claim 15, wherein the control means ensures that the heating element runs at a substantially constant temperature.

17) A device according to Claim 15 or 16, wherein the control means includes an infra-red detector to detect the amount of infra-red radiation given off by the heating element.

18) A device according to Claim 17, wherein a comparator is provided to compare the output of the detector with a reference value.

19) A device according to Claim 18, wherein the temperature of the heating element is reduced, when the reference value is exceeded by the output of the detector.

20) A device according to any preceding claim, wherein a switch is provided between the electricity supply and the heating element.

21) A device according to Claim 21, wherein the switch is a solenoid switch or a mosfet.

22) A device according to Claim 20 or 21, wherein the said switch is actuated in accordance with the output of the comparator, allowing a current to flow when the output from the infra-red detector is below the reference value, and preventing the flow of current when the output from the infra-red detector exceeds the reference value.

23) A device according to any of claims 15 to 22, wherein the control means further includes a power supply monitor which prevents a current from flowing to the heating element if the power supply cannot provide sufficient power to heat the heating element to a degree which vaporises fluid passing therethrough.

24) A device according to Claim 23, wherein the power supply monitor comprises a timer which allows current to flow to the heating element after a pre-set period of time has elapsed, thereby allowing the battery to recover.

25) A device according to any of claims 15 to 24, wherein the control means comprises a checker which checks that a current is supplied to the heating element.

26) A device according to Claim 25, wherein the output of the checker controls the pump, allowing the pump to be activated if the checker has established that a current is being supplied to the heating element, and de-activating the pump when insufficient current is being supplied to the heating element.

27) A device according to Claim 26 or 27, wherein the control means includes a timer or delay unit, to delay activation of the pump after detection of a current being supplied to the heating element.

28) A device according to any of Claims 25 to 27, wherein if the checker detects a fall in the current supplied to the heating element, the timer or delay unit does not de-activate the pump unless the fall in current supplied continues for more than a predetermined time period.

29) A device according to any preceding claim, wherein the fluid used in the device is non-toxic, and/or scented, and/or an incapacitant.

30) An alarm system comprising a device as claimed in any preceding claim.

31) An alarm system according to Claim 30, wherein the device is actuated by the sound generated by the alarm.

32) An alarm system according to Claim 30 or 31, wherein the alarm system is a vehicle alarm system.