AU2001100320A4 - Pest control spray gun - Google Patents

Description

P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION INNOVATION PATENT Invention Title: Pest control spray gun The following statement is a full description of this invention, including the best method of performing it known to us: Freehills Sydney\003922308 Printed 31 August 2001 (10:12) page 1 CEOO3915545v8.doc 1 Pest control spray gun Field of the invention This invention relates to a spray gun of a type typically used for spraying a charge or continuous stream of air with powder particles entrained in the air stream. Spray guns of this nature are used for the purposes of insect control but may have other applications as well.

Background of the invention Spray guns of the aforementioned type are typically externally powered and prior art devices include a pneumatic supply pipe for connecting the gun to a supply of air under pressure, such as a compressor or the like.

Such an arrangement can be cumbersome in that the conduit connecting the gun to the compressor tends to restrict the manoeuvrablilty of the gun and often makes access to inaccessible areas that much more difficult. For example, when treating locations above ceilings or under floors the need to be connected to the compressed air supply often means providing lengthy connecting pipes which is undesirable and can result in some areas which require treatment not being treated.

Summary of the invention According to the invention as provided a spray gun for discharging particle material entrained in an air stream, the spray gun comprising: a body including a handle and an outlet nozzle; a vessel mounted to the body for containing particular material adapted to be discharged through the nozzle; at least one electrically powered air pump mounted in the body for supply of air under pressure; air conduits linking the air pump to the vessel, and the vessel to the outlet nozzle; and actuation means for causing air under pressure to pass along the air conduits from the air pump to the nozzle to carry powder material from the vessel to pass through the nozzle.

CEOO3915545v8.doc 2 Preferably the conduits include a first section which joins the air pump to the vessel and a second section joining the vessel to the outlet nozzle. The vessel made be of cylindrical form with its axis aligned vertically. A discharged end of the first conduit may be located in the vessel and be substantially coaxial with the cylinder, so as to direct the air flow downwards in use.

Preferably the base of the vessel has an inverted conical shape. The vessel may be adapted to screw into screw threads formed on the body. Preferably the body has a protective skirt extending downwardly from the underside of the body and defining a cylindrically shaped recess into which the vessel is inserted in use.

The air pump or air pumps maybe located within the handle portion of the body and, preferably, the air pump is powered by a battery which may be located in the handle. In the preferred form of the invention there are a pair of interconnected air pumps, both mounted in the handle portion of the gun. An actuation trigger may also be mounted in the handle portion of the gun which, when depressed, will supply electrical current to the air pump or air pumps to cause actuation of the gun.

These and further features of the invention will be made apparent from a description of an embodiment thereof given below by way of example. The specific features shown in the drawings should not, however, be construed has limiting on the invention.

Brief description of the drawings Figure 1 shows a cross-sectional side view of a spray gun according to the invention.

Detailed description of the embodiments As shown in the drawing, a spray gun 10 according to the invention includes a body 12 having a barrel section 14 and handle 16. The barrel section 14 has a nozzle 18 on the forward end thereof which includes an outlet jet 20 which is optionally adjustable in order to vary the shape of the spray of the powder and air emitting from the gun in use. Another alternative will be for the jet 20 to be removably mounted to the nose 22 of the barrel section 14 for replacement with other jet shapes in order to provide an adjustment mechanism for the varying the spray shape emitting through the nozzle 18.

CE003915545v8.doc 3 A cylindrically shaped vessel 24 is mounted to the underside 26 of the barrel section 14.

The vessel 24 is adapted to contain a powder material 28 which, where the gun is to be used for the extermination of insects, may comprise an insecticide such as triflumurine.

It is envisaged that the powder material will be finely ground so that the small particle sizes of the powder are able to be entrained in an air stream and projected through the outlet jet to emit from the gun in a fine cloud or spray which can be directed at insects to be exterminated.

The vessel 24 has a relatively high length to diameter ratio so that the powder 28 in the vessel is able to be well agitated within the vessel prior to being projected out of the vessel and through the jet It will be noted that the base 30 of the vessel has a conical or concave shape and incoming air 32 is directed towards this conically shaped base to assist in the dispersal of powder within the vessel 24.

The handle 16 is hollow and contains a pair of air pumps 34 which supply air under pressure to the vessel 24 along air conduits 36. The air pumps 34 will conveniently comprise electrically powered light portable air compressors, typically driven by six volt power source.

Power for the air pump 34 is provided via a battery pack 38 located in the base of the handle 16, the battery pack 38 including the pair of rechargeable batteries 40. Optionally the battery pack 38 is separable from the remainder of the handle 16 so that recharging of the battery pack can be done separately from the gun 10. This would enable a gun to be provided with more than one battery pack so that use and recharging can take place simultaneously. The battery pack is connected to the air pumps 34 via electrical conductors 42. A trigger mechanism 44 is provided towards the upper part of the handle 16, the trigger mechanism 44 being adapted to either break or make eletrical contact between the battery pack 38 and the air pumps 34 in known manner.

In the barrel section 14 of the gun the conduit 36 includes a first section 46 which joins the air pumps to the vessel 24 and a second section 48 which joins the vessel 24 to the nozzle 18 plus. This air must past through the vessel 24 in order to past through the nozzle 18 and so doing agitating powder in the vessel 24 to thereby cause the powder to become entrained in the CEOO3915545v8.doc 4 airstream. The first section 46 of the conduit 38 terminates in a downwardly extending jet which is coaxial with the axis of the vessel 24. The jet 50 is directed towards of the apex of the conical base 30. Thus, in use, the vessel 24 will be at elevated pressure although it is envisaged that the air pressure required to spray the powder materials through the nozzle 18 will not be significantly above atmospheric pressure. Preferably the powder in the vessel 24 will not be sprayed more than between 30 and 50 centimetres. If the spray jet is too high powered this can be detrimental to the effective extermination of insects.

A downwardly depending skirt 52 is mounted to the underside of the barrel section 14 of the body, the skirt 52 having been provided with internal screw threads 54 into which external screw threads on the vessel 24 engage in order to removably mount the vessel 24 to the underside of the body 12. Optionally and O-rings 56 may be provided between the skirt 52 and the vessel 24 in order to achieve an air tight engagement between the skirt 52 and the outside of the vessel 24. The skirt serves to physically protect the vessel against damage.

Preferably the body and the vessel 24 are made from a high strength plastics material, although other materials are also envisaged.

It will be appreciated that the gun as described is relatively compact and has the distinct advantage that no air or power supply lines need to be used to link the gun to an external power source. The gun is a portable tool which can be taken into confined and inaccessible spaces and can thus be used in locations where connecting pipes or conduits would make access difficult or dangerous.

In addition, the supply of air under pressure into the vessel 24, and from the vessel 24 to the outlet nozzle 18 is such that it is unlikely that blockages will occur in the air conduits, and where blockages do occur these will generally occur only in the second section 48 which will be easily accessible from the forward end of the gun optionally, by removing the outlet jet There may be many variations to the above described embodiment without departing from the scope of the invention. For example the configuration of the conduits may vary to provide for more efficient takeup and dispersion of the powder material, the configuration of the handle and air pumps may vary, depending on the nature of the pumps selected, and where it is desirable to have the spray configuration varied, it will also be possible to have an adjustment CE003915545v8.doc mechanism, either for the outlet nozzle, or for varying the pressure of air supplied to the vessel 24. Optionally the trigger mechanism 44 may include means for varying the power supplied to the pumps to thereby provide a variable spray mechanism for the gun.

Claims (7)

1. 2. Spray gun according to claim 1 wherein the air conduits comprise a first section joining the air pump to the vessel and a second section joining the vessel to the outlet nozzle.
2. 3. A spray gun according to claim 2, wherein the vessel is generally cylindrical and aligned vertically, and a discharge end of the first conduit is located within the vessel and is substantially axially aligned with the cylinder axis and directs its airflow downwardly in use to agitate powder in the vessel.
3. 4. A spray gun according to claim 3, wherein the base of the vessel has an inverted conical shape. A spray gun according to either claim 3 or 4, wherein the vessel has screw threads formed thereon adapted to engage with co-operent screw threads on the body, and the body includes an annular protective skirt which surrounds at least part of the vessel.
4. 6. A spray gun according to any preceding claim, wherein the air pump is located within the handle, and the air pump is powered by battery means.
5. 7. A spray gun according to any preceding claim, wherein a pair of interconnected air pumps are mounted in the body.
6. 8. A spray gun according to any preceding claim, wherein the actuation means comprises an electrical switch adapted to switch on or off power to the air pump or pumps. CE003915545v9.doc
7. 9. A spray gun substantially as herein before described with reference to the drawing. Dated this 31st day of August, 2001 GEORGE DUNNACHIE ROSALIE-DAWN DUNNACHIE KIMBERLEY GRANT LAWRENCE by its attorneys Freehills Carter Smith Beadle