GB2125317A

GB2125317A - Oscillating burner spraying apparatus

Info

Publication number: GB2125317A
Application number: GB08321616A
Authority: GB
Inventors: Dr Karl-Heinz Stahl; Fritz M Fend
Original assignee: Karl-Heinz Stahl
Current assignee: Karl-Heinz Stahl
Priority date: 1982-08-13
Filing date: 1983-08-11
Publication date: 1984-03-07
Also published as: GB2125317B; DE3230184A1; CH660668A5; GB8321616D0; MY8600416A

Abstract

The apparatus, for producing pesticidal spray, includes an exhaust pipe 2 and a cooling jacket 4 which surrounds the exhaust pipe and projects somewhat beyond the free end of the exhaust pipe 2. A circumferential flow guide is fitted to the free end of the cooling jacket 4 the internal diameter of the guide being greater than the external diameter of the cooling jacket 4, and the guide 8 having at least one upstream air inlet aperture 12. <IMAGE>

Description

SPECIFICATION Oscillating burner spraying apparatus The invention relates to an oscillating burner spraying apparatus.

An oscillating column burner spraying apparatus is described for example in British Patent Nos. 1265081 and 1365277 and may comprise a resonant combustion chamber having an exhaust pipe into which a substance to be sprayed is introduced via one or more nozzles spaced from the combustion chamber such that a spray emerges from the end of the exhaust pipe.

The exhaust pipe is generally surrounded by a cooling jacket which extends slightly beyond the end of the pipe. Such apparatus is used for example for plant protection in agriculture and forestry.

The spray emitted from oscillating burner spraying apparatus of this kind is usualiy not adequately directed, owing to gusts of wind from the side. This defect occurs particularly with large burners which are used for directing spray upwards at a steep angle in order to reach greater heights.

An object of this invention is to improve the directing of the spray emitted by an oscillating burner spraying apparatus and also to reduce the temperature of the spray.

Accordingly the invention provides an oscillating burner spraying apparatus including an exhaust pipe and a cooling jacket which surrounds the exhaust pipe and projects somewhat beyond the free end of the exhaust pipe, wherein a circumferential flow guide is secured to the free end of the cooling jacket, the internal diameter of said guide being greater than the external diameter of the cooling jacket, said guide having at least one upstream air inlet aperture.

The circumferential flow guide in accordance with the invention has a directing and concentrating effect on the spray emitted and also reduces its temperature by means of its one or more air inlet apertures. An oscillating burner spraying apparatus in accordance with the invention has been particularly successful in combatting caterpillars with bacillus thuringiensis berliner and in controlling the larvae of mosquitoes with Bacillus thuringiensis israelensis.

In each case, improvements in activity of up to 20% and more were obtained, irrespective of whether the oscillating burners used were small, medium-sized or large. (The figure of 20% is given only as an approximate guide.) The flow guide may be secured to the cooling jacket by means of a connecting part, or directly by welding. For reasons of safety, a guard plate preferably covers the transition between the cooling jacket and the flow guide. Preferably, the internal diameter of the flow guide is between 1.5 and 2.5 times greater than that of the exhaust pipe, and its length is between 2.5 and 3.5 greater than its internal diameter.

Certain embodiments of the invention are hereinafter described, by way of example, with reference to the accompanying drawings, wherein: Fig. 1 is a longitudinal section through a circumferential flow guide; Fig. 2 is a longitudinal section through an alternative embodiment of circumferential flow guide; and Fig. 3 is a section on the line Ill-Ill in Fig. 2.

As shown in Fig. 1 the exhaust pipe 2 of an oscillating burner spraying device is provided with a cooling jacket 4 which surrounds the exhaust pipe 2 and projects somewhat beyond the free end of the exhaust pipe 2. Fitting onto the free end of the jacket 4 is a connecting part 6 for a circumferential flow guide 8. The internal diameter of the circumferential flow guide 8 is greater than the external diameter of the cooling jacket 4. The circumferential flow guide 8 comprises air inlet apertures 10, 12 in its end region surrounding the cooling jacket 4. The transition between the cooling jacket 4 and circumferential flow guide 8 is covered at the top by a cowl-type guard plate 14. The spray produced in the oscillating burner apparatus first passed in the direction of the arrow A out of the exhaust pipe 2.This stream of spray is surrounded by a jacket of air which enters through the air inlet apertures 10 and 12 in the directions of the arrows B and C. The spray, duly directed and cooled, passes out of the circumferential flow guide 8 in the direction of the arrow D.

In the embodiment by way of example shown, in Figs. 2 and 3, the circumferential flow guide 20 is welded directly onto the free end of the cooling jacket 22. This purpose is served, on the one hand, by the cowl-like guard plate 24 which covers the transition to the cooling jacket 22 and circumferential flow guide 20 from above and, in this case, also extends on both sides as far as the lower half of the circumferential flow guide 20 with additional pieces 26, 28. In the region of the end face of the circumferential flow guide 20, plate portions 30, 32, 34 extend radially to the cooling jacket 22, so as to form large air inlet apertures 36, 38, 40. Inside the cooling jacket 22 there is again an exhaust pipe 42 which terminates shortly before the mouth of the cooling jacket 22. The method of operation and conveying corresponds to that described in connection with Fig. 1.

1. An oscillating burner spraying apparatus including an exhaust pipe and a cooling jacket which surrounds the exhaust pipe and projects somewhat beyond the free end of the exhaust pipe, wherein a circumferential flow guide is secured to the free end of the cooling jacket, the internal diameter of said guide being greater than the external diameter of the cooling jacket, said guide having at least one upstream air inlet aperture.

2. An oscillating burner apparatus as claimed in claim 1 , wherein the circumferential flow guide includes a connecting part which is fitted onto the free end of the cooling jacket.

3. An oscillating burner apparatus as claimed in

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Oscillating burner spraying apparatus The invention relates to an oscillating burner spraying apparatus. An oscillating column burner spraying apparatus is described for example in British Patent Nos. 1265081 and 1365277 and may comprise a resonant combustion chamber having an exhaust pipe into which a substance to be sprayed is introduced via one or more nozzles spaced from the combustion chamber such that a spray emerges from the end of the exhaust pipe. The exhaust pipe is generally surrounded by a cooling jacket which extends slightly beyond the end of the pipe. Such apparatus is used for example for plant protection in agriculture and forestry. The spray emitted from oscillating burner spraying apparatus of this kind is usualiy not adequately directed, owing to gusts of wind from the side. This defect occurs particularly with large burners which are used for directing spray upwards at a steep angle in order to reach greater heights. An object of this invention is to improve the directing of the spray emitted by an oscillating burner spraying apparatus and also to reduce the temperature of the spray. Accordingly the invention provides an oscillating burner spraying apparatus including an exhaust pipe and a cooling jacket which surrounds the exhaust pipe and projects somewhat beyond the free end of the exhaust pipe, wherein a circumferential flow guide is secured to the free end of the cooling jacket, the internal diameter of said guide being greater than the external diameter of the cooling jacket, said guide having at least one upstream air inlet aperture. The circumferential flow guide in accordance with the invention has a directing and concentrating effect on the spray emitted and also reduces its temperature by means of its one or more air inlet apertures. An oscillating burner spraying apparatus in accordance with the invention has been particularly successful in combatting caterpillars with bacillus thuringiensis berliner and in controlling the larvae of mosquitoes with Bacillus thuringiensis israelensis. In each case, improvements in activity of up to 20% and more were obtained, irrespective of whether the oscillating burners used were small, medium-sized or large. (The figure of 20% is given only as an approximate guide.) The flow guide may be secured to the cooling jacket by means of a connecting part, or directly by welding. For reasons of safety, a guard plate preferably covers the transition between the cooling jacket and the flow guide. Preferably, the internal diameter of the flow guide is between 1.5 and 2.5 times greater than that of the exhaust pipe, and its length is between 2.5 and 3.5 greater than its internal diameter. Certain embodiments of the invention are hereinafter described, by way of example, with reference to the accompanying drawings, wherein: Fig. 1 is a longitudinal section through a circumferential flow guide; Fig. 2 is a longitudinal section through an alternative embodiment of circumferential flow guide; and Fig. 3 is a section on the line Ill-Ill in Fig. 2. As shown in Fig. 1 the exhaust pipe 2 of an oscillating burner spraying device is provided with a cooling jacket 4 which surrounds the exhaust pipe 2 and projects somewhat beyond the free end of the exhaust pipe 2. Fitting onto the free end of the jacket 4 is a connecting part 6 for a circumferential flow guide 8. The internal diameter of the circumferential flow guide 8 is greater than the external diameter of the cooling jacket 4. The circumferential flow guide 8 comprises air inlet apertures 10, 12 in its end region surrounding the cooling jacket 4. The transition between the cooling jacket 4 and circumferential flow guide 8 is covered at the top by a cowl-type guard plate 14. The spray produced in the oscillating burner apparatus first passed in the direction of the arrow A out of the exhaust pipe 2.This stream of spray is surrounded by a jacket of air which enters through the air inlet apertures 10 and 12 in the directions of the arrows B and C. The spray, duly directed and cooled, passes out of the circumferential flow guide 8 in the direction of the arrow D. In the embodiment by way of example shown, in Figs. 2 and 3, the circumferential flow guide 20 is welded directly onto the free end of the cooling jacket 22. This purpose is served, on the one hand, by the cowl-like guard plate 24 which covers the transition to the cooling jacket 22 and circumferential flow guide 20 from above and, in this case, also extends on both sides as far as the lower half of the circumferential flow guide 20 with additional pieces 26, 28. In the region of the end face of the circumferential flow guide 20, plate portions 30, 32, 34 extend radially to the cooling jacket 22, so as to form large air inlet apertures 36, 38, 40. Inside the cooling jacket 22 there is again an exhaust pipe 42 which terminates shortly before the mouth of the cooling jacket 22.The method of operation and conveying corresponds to that described in connection with Fig. 1. CLAIMS

3. An oscillating burner apparatus as claimed in claim 1 wherein the circumferential flow guide is welded onto the cooling jacket.

4. An oscillating burner apparatus as claimed in any of the preceding claims, wherein the transition between the cooling jacket and the circumferential flow guide is covered, at least from above, by a guard plate.

5. An oscillating burner apparatus as claimed in any of the preceding claims, wherein the internal diameter of the circumferential flow guide is 1.5 to 2.5 times greater than the internal diameter of the cooling jacket.

6. An oscillating burner apparatus as claimed in claim 5 wherein the internal diameter of the circumferential flow guide is between 1.8 and 2.2 times greater than the internal diameter of the cooling jacket.

7. An oscillating burner apparatus as claimed in any of the preceding claims, wherein the length of the circumferential flow guide is between 2 and 4 times greater than the internal diameter thereof.

8. An oscillating burner apparatus as claimed in claim 7 wherein the length of the circumferential flow guide is between 2.5 and 3.5 times greater than the internal diameter thereof.

9. An oscillating burner spraying apparatus substantially as herein described with reference to Fig. 1 of the accompanying drawings.

10. An oscillating burner spraying apparatus substantially as herein described with reference to Figs. 2 and 3 of the accompanying drawings.