Patented Nov. 16,1948
iJNlTED STATES PATENT OFFICE FLUID HEATER Nelson G. Goreau, New Orleans, La. Application June 19, 1945, Serial No. 600,365
My invention relates .to Fluid heaters in the particularly for heating water, it may be employed for heating other fluids.
One of the objects of the present invention is to obtain an increase in the thermal efficiency of the heater by providing an improved construction which embodies a casing lined with porous in sulating refractory material enclosing a combustion chamber, the walls of which are rapidly heated to incandescence by a suitable fuel burner, and placing a helical coil therein in close proximity to said lining and thereby exposing the major part of the helical coil to the intense heat radiated from the surface of the combustion chamber, thereby producing the very highest thermal efficiency while employing the least amount of coil and other material embodied in the heater.
Another object is to provide a preheating coil above and in series with main helical coil which is heated principally by convection in order to conserve heat.
Another object is to so arrange the convolutions of the coils that they will be narrowly spaced apart and that the condensate, which condenses thereon, will be conveyed away from the lower helical coil and combustion chamber and to evaporate it within the heater.
Another object is to make the heater safe by reducing the volumetric contents of the combustion chamber by venting the top and bottom of the structure, thereby relieving any abnormal pressure due to accidental ignition of gas therein.
The novel features, which I believe to be characteristic of my invention, are set forth with particularity in the appended claims. The invention itself, however, both as to organization and method of operation, together with additional objects and advantages thereof, will be best understood from the following description of a specific embodiment when read in connection with the accompanying drawings, in which,
Fig. 1 is a view of the heater partly in vertical section and partly in side elevation.
Fig. 2 is a sectional plan view on the line Z-2 of Fig. 1 and partly broken away.
Referring to the construction shown in the drawings for the purpose of illustrating the principles involved in the invention, the numeral 7 designates an outside vertical annular casing which may be constructed of any suitable material. This casing has a lining 8 of porous insu- 6 Claims. (Cl. 122-'-250)' tom of M5 by nuts 20.
2 lating refractory material which encloses a combustion chamber. This lining is bellmouthed at its lower end and is cylindrical at its upper end but its main portion is diverging upwardly.v
The combustion chamber contains a helical coil ID in proximity to the lining 8 so as to be heated by radiation from the highly heated 1ining. The convolutions of this coil are narrowly spaced apart and converge downwardly so that water condensing thereon will be conveyed away from the lower convolution andfrom the cornbustion chamber. I
The upper end of the coil I0 is connected with the lower outer end of spiral preheating coils R2, the outer convolutions of which are ver close to the cylindrical portion of the lining 8, so that these coils are heated principally by convection.
A spider with arms l3, inclined downwardly toward the center, is located below the coils l2.
Positioned centrally within the coil I0, there is a cup-like easing M which has a bottom is and is coned upwardly in spaced relation from the coil. It will be noted further from the drawings that the convolutions of the, coil ID in upward direction gradually approach closer and closer to the lining 8 while they gradually become positioned farther and farther from the casing M. The lower end of a rod 3 is secured to the bot- The rod l8 toward its upper end is secured to the arms 22 of a spider by a nut 24. The upper sides of the arms 22 are provided with vent passages 34. Standards 26 extend up from the arms 22 and support a down draft deflector 28. An escape vent pipe 30 is secured to the upper portion of the standards 26. A cover member 32 is supported at the outer ends of the arms 22 and is centrally apertured for the pipe 30, around which it is free to slide upwardly. A cold water supply pipe 36 is connected with the outer end of the coils 12.
An annular drip pan I92 is positioned below the casing l to collect water which may drip from inside of the combustion chamber. The inner casing l4 serves as a receptacle to collect water which condenses on the upper coils l2 and runs down the inclined spider arms 13.
The water which collects in these receptacles is quickly evaporated by heat from a burner 88 supplied 'by a gas pipe 86. An opening I04 over the pan Hi2 supplies secondary air to the combustion chamber while an opening I06 through the center of the pan supplies primary air to the burner.
The operation and advantages of this fluid heater will be apparent in connection with the initially into said inlet chamber and then succession between said spaced convolutions into said outlet flue.
If a large amount of gas in the combustion chamber should become ignited, it will lift the safety cover 32 to relieve pressure in the chamber and prevent damage to the structure. The down-draft deflector 28 in conjunction with the cover 32 provides for adequate venting through the vent passages 3'4 in the arms '22.
1. In combination with a fluid heater having a combustion chamber that is annular and generally of truncated cone in shape and a spiral coil having spaced convolutions, divides thechamber in a diagonal direction to form a diminishing inlet combustion chamber and an expanding'out- .let flue, and a fuel burner for projecting flame initially into said inlet chamber and then in succession between said spaced convolutions into said outlet flue.
2. The combination stated in claim 1, and a drip pan at the bottom of the heater for receiving and evaporating condensate from said coil.
3. The combination stated in claim 1, and means for admitting primary and secondary air into said burner.
4. The combination stated in claim 1, and a spiral preheating coil above the exhaust flue connected in series with the aforesaid spiral coil.
5. The combination stated in claim 1, and a cup-like member spaced within said spiral coil.
6. The combination stated in claim 1, and a top cover member loosely supported at the outlet of the heater.
NELSON G. GOREAU.
REFERENCES CITED The following references are of record in the 20 file of this patent:
UNITED STATES PATENTS Number Name Date 190,857 Herreshofi May 15, 1877 366,074 Chase July 5, 1887 421,792 Ward Feb. 18, 1890 683,995 Schlumberger Oct. 8, 1901 737,784 Sebald et a1. Sept. 1, 1903 1,309,313 Beler July 8, 1919 30 1,737,202 Runnels Nov. 26, 1929