US2625990A - Atomizing - Google Patents

Description

28 FUEL 80 0 n INVENTOR BYZ Z ATTORNEY 550/755 0. jM/T/l G. D. SMITH Filed Sept. 8, 1947 A TOMIZING OIL BURNER AND IGNITION MEANS THEREFOR Jan. 20, 1953 Patented Jan. 20, 1953 UNITED STATES PATENT OFFICE ATOMIZING 01 BURNERJANDJIGNITION iMEANs THEREFOR George D. Smith, Brooklyn, N. Y.

Application September 8, 1947, Serial No. 772,761

'1 Claim. 1

This invention relates generally to ignition means and more particularly to an ignitor for fuel in a dispersed state.

It is among the objects of the present invention to provide structure for the ignition of fuel flares or fuel flames, particularly those required to burn 'inthe atmosphere, such as fog dispersal burners which must functionin rain, wind and adverse weather conditions.

vIn connection with the dispersionof fog from such areas as airfields, it is necessary that fuel burners used for thispurpose be quickly ignitible. This is so for several reasons. First, with large areas over which the fog dispersal burners are distributed, it is desirable that they be'ignited at the exact time when their use is necessary. This may be readily understood, since if the burners do not light at the desired time, the fog dispersal is interfered with, which may cause bad landings of the aeroplanes. Another reason for prompt action is that with a large number of burners, fuel consumption is relatively high and if it were necessary to light the burners in advance of their actual use, there would be considerable waste of fuel.

vPrompt lighting of theburners is also necessary because it is most likely that it will'be necessary to ignite them when theweather conditions are adverse-accompanied by wind-andrain.

It is another object of the "present invention to provide a fuel flare or flame ignitor which, when energized willsubstantiallyremain within a predetermined rangeof temperatures so that the ignition temperature may be obtained to properly ignite theparticularv fuel being used.

Another object herein lies in the provision of structure of the class described which is simple, so as to be low in initial cost since arelatively large number of ignitors are required for a single airfield.

Another object'herein lies in the provision of ignitor structure which is substantially weatherproof so that the samemay have long continued trouble-free operation requiring a minimum of servicing.

Another object herein lies in the provision of a fuel flare ignitor which is electrically operated so that the same may be remotely controlled with a maximum of speed and con- -venience.

A feature of the inventionlies in thefact that the power requirement of the ignitor is relatively low. This permits a large number of ignitors to be operated offasingleservice line of relatively low power transmitting capacity.

Another object of the present invention lies .in theprovision of an ignitor which maintains a substantially constant predetermined temperature by virtue of the structure incorporated therein which protects the heater element from ambient external influences. In accordance with the present invention, a'heater element is used which may be energized and controlled from a remote point and in which the heater element is disposed Withina body element having a downwardly openingrecessysaid heater element being thus protected from mechanical injury and weather conditions so that with a'relatively low power input adequate constant temperature for ignition ,purposes is maintained.

The present invention has among itsfeatures the overcoming of the disadvantages associated with priorart ignitors in which becauseof the lack of protection'for the heater element, ambient external influences such as wind, fog or rain of variable intensity would'lead to the disintegration of the heater element. Thus, for example, where the wind velocity was suflicient to carry away for example, watts of energy, it was necessary to supply sufficient additional energy to bring the heater element to the desired predetermined temperature. If the wind velocity decreased, the reduction in cooling would cause the heater element to burn out. On the other hand, if the windvelocity increased, the temperature of the heater element would drop so that it was no longer effective to produce proper ignition.

Another object herein lies-in the provision of fuel burner and ignitor combination structure wherein the ignitor is stationary with respect to the burner and wherein fuel is projected by the burner toward the ignitor at the commencement of combustion, the projection of the fuel or its position receding with'respect to the ignitor after combustion has occurred for a short period of time. Thus, no moving parts or any other means are required to shift the position of the ignitor and yet, very quickly after ignition of the fuel takes place, the ignitor is in effect removed from the flame.

These objects and other incidental ends and advantages will more fully appear in the progress of this disclosure and be pointed out in the appended claim.

In the drawings in which similar reference characters designate corresponding parts throughout the several views:

Fig. 1 is a fragmentary elevational view, partly .in vertical section, showing an embodiment of the invention.

Fig. 2 is a plan view of the base element of the ignitor with the cover element removed.

Fig. 3 is a fragmentary vertical sectional view as seen from the plane 3-3 on Fig. 1.

Fig. 4 is a schematic diagram.

The ignitor, generally indicated by reference character I 0, includes broadly a body element I I, a heating element I2, a support element I3, and energy supplying means I 4.

The ignitor I is used in combination with a burner I5 and is fixed at a predetermined position with respect thereto. As seen in Fig. 1, the support element I3 is joined to the lower portion I5 of the burner element I5 by a connector element I'I. While I have shownin Fig. 1, the ignitor I0 as being fixed in position with respect to the burner I5 by the connector element I I, other suitable means for this purpose may be employed.

The burner I5 is of a type known in the art to which the present invention relates in which the flow of fuel may be controlled and the shape of the dispersed fuel cone above the burner may be controlled. While I have shown only one burner I5 and one ignitor I9, as will be obvious, any desired number of these units, indicated generally by reference character 25, may be arranged in suitable fashion to accommodate the area being cleared of fog. The burner I5, when operating under low pressure, controlled for example by the input valve 28 and the output valve 29, may have an initial broad based inverted cone of dispersed fuel disposed above it. The relatively outer margins of such a cone are indicated by the dot dash lines on Fig. 1 (reference character 40). the pressure of the fuel in the burner I5 builds up to equilibrium value, the cone ofdispersed fuel narrows so that the same may be indicated, for

example by the dash double dot lines on Fig. 1 (reference character 50). Thus, immediately following the manipulation of the valves 28 and 29 to set the fuel supply for a smaller or larger quantity, the initial cone of dispersed fuel for a When particular setting of fuel supply will contact the?v ignitor I0 and after pressure has reached a state of equilibrium, the cone will automatically narrow so that the ignitor I0 is no longer located within the area of most intense heat.

Turning to the ignitor III, the body element I I and the support element I3 are preferably composed of suitable heat resisting material. This, for example, may be of molded electrical insulating and heat resisting material. Molded asbestos of this character may be used for this purpose. The body element I I includes a base member 25, and a cover member 2 I. The base member 20 includes a bottom surface 22, a top surface 23, a rear surface 24, a front surface 26 and side surfaces 21 and 30. Rearwardly of the front wall 26, the base member 20 is provided with an opening 33 of elongated character extending lengthwise between the side surfaces 2'! and 30. The opening 33 has a front wall 34, a rear wall 35 and side walls 35 and 31. The base member 25 is provided with a plurality of orifices to receive contact and assembly screws II-42 and 4344 re- The cover member 2I has a bottom surface 45/ a top surface 45, a rear surface 41, a forward of them are set to 4 surface 48. The front surface 48 is preferably coplanar with the surface 26. The side surfaces 5I and 52 are preferably co-planar with the side surfaces 21 and 30.

There is a front recess 55 and a rear depresion 56. The depression 56 is of sufficient depth and size to accommodate the upper ends of the contact screws AI and 42 together with the conductors 6B, and GI as Well as the terminals of the heating element I2 and the washers and nuts thereon.

The front recess 55 includes a top surface 62, side surfaces 63 and 64, a rear surface 65 and a front surface 65. The front surface 66 is coplanar with the front surface 25. The rear wall 65 forms a web separating the front recess 55 from the rear depression 55, and is provided with a pair of spaced indentations where the terminals of the heater element I2 may pass rearwardly to become secured upon the contact screws 43 and 44. The lower portions of the screws 4| and '42 are countersunk at their heads in the lower wall surface 22, while the lower of the two nuts on each of said screws is countersunk in the top surface 23. The heater element is preferably in the form of a coil of resistance wire, and is desirably stiff enough to support itself even when at high temperature.

A mounting block I9 is suitably secured in the upper open end of the support element I3, the latter preferably being in the form of tubing which is rectangular in cross section. Block I9 has a pair of orifices through which the screws 43 and 44 upwardly project and the lower of the two nuts on each of said screws is countersunk in the upper surface 23. These last mentioned nuts hold the base member 23 on top of the support I3. The cover member 2| also has a pair of holes through which the upper ends of the screws 43 and 44 project, and the top nuts hold the cover member in place.

Operation toward the opening of the burner through which the fuel emerges, said cavity, however being laterally offset with respect to the axis of the principal direction of fuel movement as it leaves the burner.

When it is desired to ignite the burner I5, the switch is closed which completes the circuit from a source of electricity (not shown) to the stepdown transformer 8|. The secondary Winding of the transformer is connected via the conductors 60 and BI through the contact screws 4| and 42 and associated conductive parts to the heater element I2. The action of ignition and the inception of combustion is relatively rapid and the operation, as presently understood i as follows: The heater element I2 quickly reaches the predetermined temperature which of course is determined from the flash point of the fuel used. Depending upon the particular type of 7 burner used, the valves 28 and 29 or either one permit the fuel to emerge from the burner. In the beginning, the fuel at the selected setting, because of inertia or for other reasons (even deliberate control), leaves the burner at a relatively wide angle (see the cone '40. on Fig. 1). Fuel, either in the form of a condensation of droplets or in the form of a spray or a gas or liquid, is deposited within the recess 55 and/or upon the heater element I 2.

The heater element quickly ignites this deposited material, which in turn expands and flashes back and -is forcibly ejected to ignite the main fuel stream leaving the burner l5. By virtue of the shape of the recess, the burning material must of necessity leave the recess through the opening and therefore move generally in the direction of the fuel stream. Immediately after ignition, the inertia of the fuel is overcome and the velocity of the fuel stream is increased by reason of increase in pressure so that the cone of said stream becomes narrowed (see reference character 50 in Fig. 1). This results in a recession of the fuel stream away from the ignitor and depending upon the pressure and flow of the fuel is accompanied by a movement of the base of the flame away from the burner opening. This, together with the ambient air which is pulled along with the flame results in the envelopment of the ignitor by cooler air with a consequent protection of the ignitor from the areas of intensely high temperature.

The heater element may be relatively small and is preferably one having a low thermal capacity in the order of 30 watts; heater elements of such size having been successfully operated, and have successfully performed with as low as watts. Through the use of low voltage supply to the heater element, since the ignitors are principally used in locations exposed to bad weather conditions, the frequency of electrical trouble, such as short circuit, or leakage is reduced.

It may thus be seen that I have disclosed an ign-itor that will effect ignition and remain away from the flames without the need for any movable parts or any other means to remove the ignitor from the flame area, and that the natural movement of the fuel causes an upward current of air which tends to keep the ignitor housing cooler than it would otherwise be.

I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art.

I claim:

In an oil burner the combination of a burner element having an nozzle, an ignition device, a support for joining and permanently holding said burner element and said ignition device in fixed off center relation to each other, said ignition device including a standard and a cap therefor, said cap member forming a relatively short unrestricted recess which has its opening forwardly of and pointed toward the nozzle of said burner element, a hot wire igniting element mounted in said recess near the closed end thereof to protect said igniting element from foreign particles and air currents tending to cool said element, means for supplying fuel under reduced pressure to said nozzle to atomize said fuel and to spray it in a predetermined wide cone area at the start of fuel supply to said nozzle and in a narrower predetermined cone area when the fuel pressure at the nozzle has reached its equilibrium value, said igniting element being within said Wide cone area whereby it is in direct unobstructed line with a portion of atomized fuel of said wide cone at the start, whereby said atomized fuel emerging from said nozzle at the start is partly intercepted by said recess of said ignition device and whereby said igniting element receives and ignites some of said atomized fuel in said recess, said recess also constructed to act as a chamber with its axis so directed as to direct ignited atomized fuel into igniting relationship to the remainder of the atomized fuel-issuing from said wide cone area of said burner nozzle, said ignited fuel in said recess upon expanding being forcibly ejected from said recess into the main atomized fuel stream to ignite the same, said ignition device being entirely outside the narrower fuel cone area during normal operation.

GEORGE D. SMITH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,646,503 Steward Oct. 25, 1927 1,670,819 Morris et a1. May 22, 1928 1,704,875 Vaughn Mar. 12, 1929 1,724,132 Hart Aug. 13, 1929 1,740,249 Klees Dec. 17, 1929 1,826,788 Huber Oct. 13, 1931 2,005,832 Vidalie June 25, 1935 2,150,687 Konowich Mar. 14, 1939 2,384,797 Cerny et a1 Sept. 18, 1945 2,410,881 Hunter Nov. 12, 1946 2,423,410 Simmons July 1, 1947 2,438,823 Resek et a1 Mar. 30, 1948 2,465,092 Harkness et a1 Mar. 22, 1949 2,483,975 Hoogendam Oct. 4, 1949

Images