US3013602A

US3013602A - Radiant gas burner

Info

Publication number: US3013602A
Application number: US610467A
Authority: US
Inventors: Heimerl Otto
Original assignee: American Infra Red Radiant Co Inc
Current assignee: American Infra Red Radiant Co Inc
Priority date: 1956-09-18
Filing date: 1956-09-18
Publication date: 1961-12-19
Anticipated expiration: 1978-12-19

Description

Dec. 19, 1961 o. HEIMERL RADIANT GAS BURNER Filed Sept. 18, 1956 FIG. 2

FIG.

FIG. 4

I r ll ATTORNEYS 3,013,602 Patented Dec. 19, 1961 tire 4 3,013,602 RADEANT GAS BURNER (Etta Heimerl, Kola Kath, Germany, assignor to American Infra Red Radiant (30., inc, Houston, Tex., a corporation at Delaware Fiied Sept. 18, 1956, Ser. No. 610,467 4 Claims. (Cl. 158-414) The present invention relates to gas heating appliances.

In gas heating appliances of the type to which the present invention relates, provision is made for a radiation burner or radiator having a plate-like gas permeable closure. This closure is rendered incandescent by the combustion of gas on its surface. The resultant heat, transmitted primarily by radiation, may be used for heating, cooking or for medical and therapeutic purposes. The gas-air mixture is supplied to the burner chamber, formed by the radiator housing and the burner closure plate, by a mixer pipe, which has its outer end disposed outwardly of the housing and which outer end is provided with an injector through which the passing gas draws in the requisite air to provide the gas-air mixture.

It was formerly believed that in order to achieve thorough mixture of the gas with the air, a maximum length of common flow path of the gas and the air, between the point of combination thereof in the injector and the point of emergence thereof into the chamber, was required. The mixer pipe in gas mixers of the prior art extends substantially over the entire length of the burner chamber and does not open into the burner chamber until its innermost end, just ahead of the end wall of the burner chamber transverse to the mixer pipe. At the point of emergence, the major portion of the gas-air mixture is deflected by 180 degrees so that at this point a considerable static pressure and an undesirable stagnation of the mixture results. The pressure distribution in the burner chamber becomes non-uniform, with resulting non-uniformity of the flow of gas undergoing combustion per unit area. Since, in various parts of the burner chamber, a substantially lower pressure of gas-air mixture is established than elsewhere in the burner chamber, this mixture will flow through the burner closure plate at those points, where the latter will therefore be heated to a lower temperature than the rest of the radiation surface.

In view of the foregoing, it-is an object of the present invention to obviate the foregoing disadvantages of the prior art.

Pursuant to the foregoing object, it is another object of the invention to provide a mixer pipe which has, over most of the extent thereof which is disposed in the burner chamber, means for providing outlets for the gas-air mixture within the burner chamber.

The above and other objects, features and advantages of the present invention will be more fully understood from the following description considered in connection with the accompanying illustrative drawings.

In the drawings which illustrate the best modes presently contemplated of carrying out the invention:

FIG. 1 is a top plan view of a burner pursuant to the present invention, parts being omitted for purposes of illustration;

FIG. 2 is a sectional view taken on the line 2-2 of FIG. 1;

FIG. 3 is a sectional view taken on the line 33 of FIG. 1;

FIG. 4 is a view similar to FIG. 3 and illustrates a modification; and

FIG. 5 is a view similar to FIG. 2, but with parts omitted and illustrates another modification.

The present invention is based upon the realization or discovery that the achievement of a thorough mixture of common flow path for both the gas and the air, but rather primarily a deflection with some degree of vortex forma-.

tion. Since, in accordance with the present aspect of the invention, the mixture of gas and air enters the burner chamber of the gas heating appliance over much of the total length of the mixer pipe, or even over all of it, a very uniform pressure disposition is established in the chamber, resulting in a uniform temperature distribution over the entire surface of the burner closure plate. Through avoidance of deflection of the emerging mixture by degrees, no static pressure is generated at the point of emergence of the mixture pipe, and the flow resistance of the burner is substantially diminished. This is of great importance with respect to the low pressure of gas used in such heating appliances, as it augments the gas capacity and hence the heating power of the appliance.

Referring now to FIGS. 1, 2 and 3 of the drawings in detail, there is illustrated a gas heating appliance 20 pursuant to the present invention. The appliance 20 is provided with a burner closure wall 22 which is composed of four gas permeable plates 24, of which only one plate is illustrated herein. The burner elements or members 24 are preferably of the type illustrated and described in the copending application of Gunther Schwank, Serial Number 214,468, filed March 8, 1951, and assigned to the assignee hereof, now Patent No. 2,775,294, granted December 25, 1956. The burner elements 24 sit loosely in a frame 26. The frame extends completely about the burner wall 22, being provided with an inturned flange 28 which overlies the front surfaces of the burner elernents 24 and which is provided with an inner surface 30 which provides a lateral bearing surface for the various burner elements. The frame i also provided with integral cross pieces or

partitions

32 and 34 respectively, so as to define with the outer periphery of the frame the separate box like compartments 36, each of which accommodates one burner element 24.

Provision is made for a housing 38 which is of generally dished or tub-like conformation. The housing 38 is provided with a lateral flange or rim 40 on which there is engaged a complementary flange or rim 42 provided on the frame 26, said rims being secured together in any suitable manner, for example by screws (not illustrated). The housing 38 is also provided with a column or post 44 which extends from the floor 46 thereof. It will be noted from FIGS. 1 and 2 that each burner element 24 is supported between the frame 26 and the upper surface or face 48 of the flange 40. In this connection, it will be apparent that each burner element is disposed on said face 48 along two of the marginal edges thereof and it will be noted that the four adjacent inside corners 50 of the burner elements 24 are supported by the post 44.

The mixer or pipe 52 for the combustion mixture, as here shown, comprises a substantially semi-circularly curved sheet of metal 54 and the confronting floor 46 of the burner housing 38. The pipe has a gap or slot 56 which opens into the burner chamber 58 and is also provided with an opening 60 for the column 44. Should it be necessary to reduce the resistance to the flow in the mixing tube 52 which is offered by the post 44, the post may either be streamlined or it may consist of a relatively narrow part which extends through the mixer pipe 52 and a supporting plate may be provided on the top thereof. The mixer pipe is supported at one end thereof by a projection or boss 62 which is cast into one end wall of the burner housing, and at the other end thereof by a boss or projection 64 which is cast into the other end wall of the burner housing, the sheet metal part 54 being secured to the boss 64 as by the bolt 66. Pipe 52 extends longitudinally of housing 38 for substantially the full length thereof and increases progressively in cross sectional area longitudinally thereof in a direction extending from its inlet at boss 62, as best seen in FIG. 1. The gas-air mixer nozzle is indicated by the reference numeral 68 and the gas supply line is indicated at 70.

In the embodiment illustrated in FIG. 4, the mixer tube comprises also a substantially semi'circularly curved sheet of metal 54' and a portion 74 of the floor 46' of the burner housing 38'. It will be noted that the portion 74 is shaped so as to conform to the semi-circular shape of the part 54 so as to provide a mixer tube 52 which is almost circular in cross section.

In the embodiments illustrated in FIGS. 3 and 4, the outlet port or opening in the mixer tube, which communicates with the burner chamber, comprises the gap or slot 56 which is defined on each side of the mixer pipe, longitudinally thereof, just above the floor of the housing. However, it is within the scope of the present in vention, to provide separate holes or apertures 56 (FIG. 5), in lieu of the continuous slot or gap 56, some of which apertures may, if desired, he provided at the top of the semi-circular part 54. In addition, it is within the scope of the present invention to use structural parts other than curved sheet metal for the parts 54 and 54'. For example, and not by way of limitation, castings may be used in lieu of said metallic parts.

It will be apparent that all of the burner elements 24, which collectively define the cover plate 22, may be removed from the frame 26 and said elements may be replaced when the frame is removed from the burner housing 38. Once the frame has been removed, the interior of the burner chamber 58 is readily accessible and it will be apparent that after the bolt 66 is loosened or removed, the interior or inner surfaces of the mixing tube 52 are also readily accessible.

The frame 26 may be formed in any suitable manner. For example, it may be made of cast iron, it may be injection die cast, or it may consist of bars which are welded together, or the frame may be stamped out of sheet metal.

While I have shown and described the preferred embodiments of my invention, it will be understood that various changes may be made in the present invention without departing from the underlying idea or principles of the invention within the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In a radiant heater, comprising a casing having an inlet for a combustible gaseous mixture and an outlet opening for said combustible mixture, and gas-permeable closure and burner means mounted on said casing over said opening and providing a radiant burner surface externally thereof,'said casing having an internal wall spaced from and in confronting relation to said closure and burner means; tubular means disposed in said casing in the space between said burner means and said internal wall and connected to said inlet for distributing the gaseous mixture to said burner means for passage therethrough, said tubular means extending longitudinally of said casing for substantially the full length thereof and increasing progressively in cross sectional area longitudinally thereof in a direction extending from said inlet, said tubular means having an external wall surface in spaced confronting relation with the inner surface of said burner means and having outlet means along substantially the full length of said tubular means, said external wall surface being laterally curved and extending from said outlet means in a direction toward said inner surface of said burner means, so that said gaseous mixture is discharged from said outlet means in streamline fashion along substantially the full length of said tubular means for distributing said gaseous mixture at substantially uniform pressure over the area of the inner surface of said burner means, said outlet means being substantially closer to said internal wall of said casing than to the inner surface of said burner means.

2. A radiant heater according to claim 1, further characterized in that said tubular means has a laterally curved internal wall surface, said internal wall of said casing having a laterally curved portion in confronting and spaced relation with said internal wall surface of said tubular means, said space between said laterally curved portion of said casing and said internal wall surface of said tubular means providing said outlet means of said tubular means.

3. A radiant heater according to claim 1, further characterized in that said outlet means comprises laterally spaced openings extending along substantially the full length of said tubular means.

4. A radiant heater according to claim 1, further characterized in that said casing has opposite side walls spaced laterally of said tubular means and supports said burner means in position in spaced relation to said tubular means adjacent the latter, and in the provision of a removable frame for removably securing said burner means to said casing in said position.

References Cited in the file of this patent UNITED STATES PATENTS 595,988 Brock Dec. 21, 1897 740,150 Lawler Sept. 29, 1903 1,507,791 Packer Sept. 9, 1924 1,630,878 Wilson May 31, 1927 1,682,148 Risinger Aug. 28, 1928 1,812,315 Baumgartner June 30, 1931 2,037,496 Bryant Apr. 14, 1936 2,242,742 Bobo May 20, 1941 2,395,868 Hahn Mar. 5, 1946 2,543,688 Coriolis et al. Feb. 27, 1951 2,572,273 Miller Oct. 23, 1951 2,755,851 Dow et al. July 24, 1956 2,775,294 Schwank Dec. 25, 1956 2,832,331 Schwank Apr. 29, 1958 FOREIGN PATENTS 494,087 Great Britain Oct. 17, 1938 741,660 Great Britain Dec. 7, 1955