shown in fig1 is a portable device which may be carried by a user or placed in , for example , a room or another location . the device comprises a first or top member 2 and a second or bottom member 1 . the second member 1 houses a pair of batteries 7 and an electrical circuit board 8 which is mounted flush with the top surface of the member 1 . the electrical circuit board 8 ( pcb ) may be double - sided and form a partition or dividing panel between the first member 2 and the second member 1 . electrical components forming an electrical circuit means may be located on a first side , a second side or both sides of the board 8 . it is to be noted that the device in an alternative arrangement may be constructed in a single piece such as through injection moulding rather than two separate members 1 and 2 . in one embodiment , all electronic components and connections are mounted on the lower side of the circuit board 8 , in other words within or facing the interior of the member 1 . a heater means 11 is located on the upper side of the electrical circuit board 8 mounted flush with the upper or top surface , such that the heater means 11 protrudes into member 2 to be in contact with chemical formulation . in another embodiment , the heater means 11 , a switch 6 and an indicator 5 are mounted on the same side of the electrical circuit board 8 . where the device is a singular construction or formed of two detachable members 2 and 1 , a partition forming either a single or double - sided electrical circuit board 8 may divide the device into two compartments . the first compartment may house a recess or receiving means ( see fig4 and 5 ) and have apertures 3 while the second compartment houses the power supply 7 . the heater means 11 is preferably in the form of a microheater element and more particularly an impedance means such as a resistor . the batteries 7 supply power to the electrical circuit board components which in turn deliver a series of pulses to the heater means 11 in order to heat the heater means 11 . the batteries are mounted in such a manner that the positive end of each battery 7 connects to a positive battery terminal 9 and the negative end of each battery 7 connects to a negative battery terminal 10 . typically aa batteries are used but any other form or size of batteries may be used , such as aaa batteries . the lower member 1 also has a switch means 6 used to turn the device on and off and to allow the user to control or provide additional bursts of vapour when initially turning the device on . alternatively there may be a further mode , such as a high burst mode , which the user can move the switch to in order to provide additional bursts of vapour . pulses maybe supplied to the heater means 11 via a suitable power supply . also shown adjacent the switch means 6 is an indicator 5 to provide an indication to the user where , for example , the resistor or microheater element 11 burns out or where the batteries are running low . when used to indicate the resistor 11 burning out or having some other fault , the indication might be provided by the light not turning off if a high resistance is sensed . a battery ok indicator may be instituted by using a led indicator turning on for some seconds , then off , or beeping if the battery is satisfactory . alternatively the indicator may be used as a led or a buzzer or an indication scheme analogous to car indicator lights , for example , a correct device operation as indicated by on for several seconds then off when device is first turned on . failure to light means battery failure and failure to go off means the device or resistor has failed in some manner . all of these indicators are necessary as the effect of the product is invisible in terms of the fragrance or insecticide being released and , as it is also inaudible the only indication of a flat battery or a blown microheater element 11 will mean that the consumer suffers bites or is not aware of any fragrance . the first member 2 , which may be detachable from the lower or first member 1 , has a series of apertures 3 , forming a vent , and an opening 4 for receiving a cartridge type device which provides chemical formulation , such as insecticide or fragrance . specifically the cartridge has a reservoir which contains the insecticide or fragrance and has a wick which is in constant contact with the insecticide or fragrance such that the chemical formulation is transferred through the wick from one end to the other end of the wick , with the other end of the wick being in contact with or close to a microheater element . such a cartridge device is described in copending british patent application numbers 0317183 . 2 and 0410431 . 1 to the present applicant . when the heater element heats up it thereby vaporises the chemical formulation in the wick in the vicinity of the heater and is dispersed through the series of apertures 3 into the surrounding atmosphere . the opening 4 provides entry to a recess which has guides 12 on either side of the recess ( see fig4 and 5 ), into which the edges of the cartridge fit thereby guiding the cartridge through the recess towards the inner end of the recess . adjacent the inner end of the recess is located the microheater element 11 . the recess additionally has a pair of projections or lugs , one on each side , that provide an interference fit with corresponding notches or indentations in the cartridge , one on each side . once the notches fit with the lugs it provides an indication to the user , through tactile feedback , that the cartridge is correctly located such that the wick means is in direct contact with the microheater element 11 or otherwise in the correct location . release of the vapour from the cartridge is provided through a pair of apertures located either side of the wick means in the vicinity of the microheater element 11 . alternatively , the recess may have a pair of notches or indentations , one on each side , that interference fit with a corresponding pair of projections or lugs , one on each side , on the cartridge . thus in use the cartridge is inserted by the user through the opening 4 to the recess via the guide means 12 , which may incorporate the aforementioned lugs or notches ( not shown ), or the device may already be fitted with such a cartridge having a refill pack housing the chemical formulation . the user then turns the device on through the switch means 6 and may initiate a burst mode to provide additional bursts of the vapour through the vents 3 . the use may be for instant personal use or be left by the user in a room , such as a bedroom , switched on in situations where insecticide is to be dispersed at regular intervals into the room over a set period of hours . the device may have a clip to be attached to a user &# 39 ; s clothing or belt or the like . once an indication is provided to the user through the indicator 5 that the battery is low or the microheater element is faulty then the user simply replaces the batteries or the heater element . a user may regularly check that enough chemical formulation is stored in the reservoir and if it is low or there is no formulation left then it is simply a matter of removing the cartridge from the device and replacing it with a refill cartridge , or alternatively , refilling the present cartridge reservoir .
a device for enabling vapourization of a chemical formulation into an atmosphere comprising means for receiving a cartridge including the chemical formulation , aperture means to enable vapourized chemical formulation to be guided therethrough into the atmosphere , wherein the chemical formulation contacts a heater means in order to vapourize the chemical formulation .