US1250160A - Heating apparatus. - Google Patents

Description

1. GOOD.

HEATING APPARATUS.

APPLICATION FILED MAILQ, I916.

Patented. Dec. 18,1917.

2 SHEETS-SHEET l.

1. GOOD.

HEATING APPARATUS.

APPLICATION FILED MAR. 9. 1916.

Patented Dec. 18, 1912'- 2 SHEETS-SHEET 2- W wuewfoz JOHN GOOD, OF BROOKLYN, NEW YORK.

HEATING APPARATUS.

Specification of Letters Batent.

Application filed March 9, 1916. Serial No. 83,033. 4

To all whom it may concern:

Be it known that 1, JOHN G001), a citizen of the United States, residing in Brooklyn, in the county of Kings and State of New York, have invented the following described new and useful Improvements in Heating Apparatus. 1

The invention is an improvement in forced draft burner mechanism using kerosene or heavier oils or liquid fuels, and provides means of high efficiency and extreme simplicity, whereby high temperatures can be directly and quickly obtained from the combustion of such heavy fuels without preliminary heating of either the fuel or the air and particularly whereby such heavy fuels can be ignited in their initial cold condition, and whereby also various other advantages and economies are available over existing means for burning liquid fuels, as will be made apparent in the description below. The invention further provides means whereby said quickly attained high.

temperatures may be produced in a. confined passage entirely closed from communication with the external atmosphere and therefore protected against fire hazard, and

in this latter respect the present invention is an improvement upon my prior application Serial No. 822,813, filed March 6th, 1914, which attains a like'object. The particular improvement upgn said prior application is in the elimination of the high pressure-air for producing a fuel spray which is ignitible in a cold state, that result being accomplished according to the present invention by a single source of low pressure air and a Venturi tube in certain relation thereto and to the fuel supply, as hereinafter explained. Other objects and advantages of the invention supplemental toand vindependent of those above described, "will become apparent to'those skilled in this art from the following description, and the essential structure of the means for producing such results is pointed out in the claims appended hereto.

The accompanying drawings illustrate several forms of the invention, the preferred form of the inclosed Figure 1 being to the air type;

Fig. 2 a top plan thereof;

type a simple form of the bpen including Fig. 3 a modification applicable to either typ and Fig.4 a longitudinal section of the preferred inclosed type. I

.In Fig. 1, the reference 1 denotes an ordinary belt-driven fan blower, which is to be understood as representing any suitable supply of air at low'pressure and in volume appropriate to the requirements of the apparatus. Various types of ainpropelling means are available for use for this purpose, the suitable pressure being from one quarter of a pound to two pounds per square inch, and not necessarily higher than two pounds, The supply of air at this low pressure is conducted by an air pipe 2 to a Venturi tube 3, into which fuel is introduced by a nozzle 4, connected through a needle-valve 6, to a liquid chamber 5, the liquid level wherein is somewhat lower than the orifice of the nozzle. The Venturi tube 3 is designed according to the principles of Venturi-tube design well known to the art and with reference to the air, delivery from the blower or source ofair pressure, and so as to create a considerable pressure depression at itsthroat or narrowest diameter without unduly obstructing the flow of the air through it or building up an undue back pressure in the pipe 2. The nozzle 4 is mounted to discharge into the region'of such pressure depression and preferably directly at the throat or narrowest part, where the velocity and depression are both at their maximum. Discharge of the liquid fuel is accomplished by the effect of such pressure depresslon, that is to say, as the result of the difference of pressures existing at the throat and upon the surface of the liquid in the chamber 5, which latter pressure may be atmospheric or otherwise, as desired. In other words, the liquid fuel is sucked through the liquid pipe and nozzle by the relative vacuum in the venturi, and in certain definite proportion to the'amount'of air passing through the latter, and directly under the control of such air flow. By adjustment of the needlevalve 6, or of the surface pressure in chamber 5, the liquid fuel can be automatically introduced to the Venturi tube in such appropriate and predetermined proportions with reference to the air that the resulting spray or mixture of air and kerosene or other heavy Patented Dec. 18, 1917.

readily accomplished by no greater source of heat than an electric lighted taper. In the open invention shown in Fig. 1, the air necessary fortthe continued combustion of the ignited Venturi spray may be derived by contact with the surrounding atmosphere, the general effect andaction after ignition being somewhat the same as in the familiar blow torch, but with the difierence just noted that the heavy fuel oil is ignited and burned in spark or by a type form of the an initially cold state and suffices to producean extremely high temperature immediately upon such ignition. The cold ignition of the relatively non-volatile fuel oils in apparatus constructed as above described, occurs from the cooperating effects of the considerable pressure depression and high velocity peculiar to the Venturi tube, and the relation thereto of the oil delivery, and which I believe myself to be the first to have utilized in the present relation. The liquid chamber 5 may conveniently be a float-controlled chamber such as in common use in carbureters for internal combustion engines, the same being supplied by a pipe 7 from some larger 'source of fuel, but any other means of supplying liquid fuel in the necessary proportion and at a substantially constant rate with reference to the air flow through the Venturi tube, I believe may be used with equal efiect.

Fig. 3 represents modified by first around the same apparatus leading the air; from the blower and in contact with the wall of the Venturi tube before admitting it to the entrance end of the latter, the efi'ect being to keep the tube cool by contact with the incoming air and to warm such air accordingly, before mixing the fuel with it. Manifestly such advance heating of the air takes place only after the device has been started inoperation and after the Venturi spray has been ignited cold.

The inclosed type of heating apparatus shown in Fig. 4, comprises an air source represented as a so called geared blower, marked 8, but equivalent to any suitable means of creating a low pressure supply of air. This source of air is connected by an air passage 9 to a Venturi tube 10, similar in design and purpose to the Venturi tube above described and supplied with heavy liquid fuel from apparatus of the same description and bearing the same reference characters, but the delivery end of the Venturi tube is disposed within the walls of the casing or structure in which the tube is mounted, and within which the flame is produced and confined when the apparatus isin action. Ignition is accomplished by an electric spark umpingthe gap between the hatc et hook-shaped electrodes 11 of two separate spark plugs 12, mounted in the same walls and connected to a suitable source of current, not indicated in the drawing. The spark gap intercepts the blast from the Venturi tube, being placed close to the orifice of the latter, and the extremities of the electrodes are turned convergently downward so that any liquid tending to accumulate thereon, and which might short-circuit the gap, will be blown back along the respective electrodes, or elsebe blown 0H bodily, thus keeping the gap clear at all times. The spray issuing from this Venturi tube, as in the form first described, is ignitible in a cold state but its proportions give a mixture somewhat richer in fuel than the Venturi tube 3. A single spark is ordinarily suficient to ignite it, although it is preferred to operate the ignition means continuously when the heating apparatus is called upon only for intermittent service of short duration. For this purpose an ordinary magneto geared with the blower 8, or an induction coil and batteries, or other equivalent continuous sparking mechanism, is appropriate and satisfactory. The ignited'spray takes the air needed for its continued combustion within the closed and imperforate wall of its inclosure, from the supplemental air channel 13, which, however, is supplied from the same air source as the Venturi tube, all j the airthat does not pass through the Venturi tube being passed through the supplemental air channel 13 and desirably so as to join the burning spray uniformly on all sides thereof and just beyond the point of ignition. The damper 14: which controls the relative proportions of the main and supplemental air flows establishes that high velocity of flow through the venturi which is necessary to create a mixture, ignitible cold at the outlet end, such high velocity being of particular importance in this connection. When the damper is once set it needs no further attention and of course it could be omitted when the supplemental channel possesses initially the appropriate restriction. Theefi'ect of the damper as just explained is supplemented by forming the burner casing with a further Venturi restriction at or close to the outlet of the Venturi tube 10, so that an auxiliary difierence of pressure is thus created between the two ends of the spraying venturi which further augments the velocity through it and enhances the mixture of the spray and air. Substantially complete combustion is established within the closed casing of the apparatus and the heat thereof is utilized by leading the flame through a relatively narrow passage which is preferably of such length that only wholly consumed gases emerge at the ultimate outlet. In the pres ent case, the flame passage,

which may be Said to begin at the ignition point, is constituted by the divergent end part of the burner caslng, and the annular or bowlshaped space 16 formed between the exterior surface of the vaporizer plate 17 of a hot-plate oil engine, and a wall 18 of heatinsulating material surrounding the hot plate. The flame impinges directly upon the vaporizer plate and spreads out uniformly on all sides to an annular chamber 19, around the margin of the plate, whence it escapes from one or more pipes 20, to a remote discharge, that is to say, to some place where the products of combustion can be safely dissipated into the atmosphere. The heating effect is augmented by-the direct impingement of the flame and also by making the transfer space 16 relatively thin or shallow, even more so than indicated in Fig. 4, but it will be apparent that various ways may be resorted to for utilizing the heat ofthe flame while confining it within v a closed flame passage out of contact with the external atmosphere. The walls of the casing which-forms the flame passage, are imperforate so that the flame therein which is under pressure can escape only through the exhaust, and accidental explosions therein are safely confined, and the same is also true of the air passage leading from the air source to the point of ignition; an explosion is either stifled by the wings of the blower, or with other types of air supply harmlessly vented at the intake. Such confinement or inclosure of the air and flame passageshas particular advantage in hot-plate oil engines in that it enables them to be prepared for starting on their normal working cycle in a minimum time and without exposing flame to the engine room. In such case the out-take pipe or pipes 20 are connected to the exhaust pipe of the engine.

In the particular construction of burner casing illustrated in Fig. 4, the Venturi tube 10 is separately formed and held in place in relationship described, it being observed that the complete inclosure of the flame passage and igniting means provides an apparatus in which combustion is established and continued, solely by the operation of two outside agencies, to wit, the air source and the igniter, and that these may "be brought into operation by any simple or single mechanism. In other words, the present invention provides the means whereby the operator may readily and instantly, as by throwing a handle or lever, start and continue combustion of heavy fuel 'oil in a safely confined passage where the heat of its combustion can be utlized for Whatever purpose required. In this closed form of the heating device, the flame passage should be of small cross-sectional area from the ignition point through the region in which the heat of the flame is utilized, so that the gases moving therethrough shall have continued high velocity and thorough mixing, thereby attaining the highest temperature and best results, but the velocity should not be greater at the point of ignition than the rate of propagation of flame through the mixture.

I claim:

Heating apparatus comprising a passage connected with a source of air and terminating in a Venturi tube, means for supplying liquid fuel to form in said tube a mixture which ignites in a cold state, and a chamber in said passage surrounding said tube, whereby the heat resulting from such igniticion preheats the air flowing through said tu e. v

In testimony whereof, I have signed this I specificatiom JOHN GOOD.

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