US3144073A

US3144073A - Burners

Info

Publication number: US3144073A
Application number: US92308A
Authority: US
Inventors: Ronald D Corey
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-02-28
Filing date: 1961-02-28
Publication date: 1964-08-11
Anticipated expiration: 1981-08-11

Description

R. D. COREY Aug. 11, 1964 BURNERS 2 Sheets-Sheet 1 Filed Feb. 28, 1961 FIG.

FIG.2

FIG.5

INVENTOR.

RONALD D. COREY FIG.8

ATTORNEY FIGS R. D. COREY Aug. 11, 1964 BURNERS ,2 Sheets-Sheet 2 Filed Feb. 28 1961 FIG. 10

FIG. 11

FIG. 12

United States Patent 3,144,073 BURNERS Ronald Corey, RD. 1, Box 293, Cortland, N.Y. Filed Feb. 28, 1961, Ser. No. 92,308 7 Claims. (Cl. 158-7) This invention relates to devices for burning fluid combustible mixtures, and especially to burners and burner grids for use in such service.

In the operation of fluid fuel burners which consume fluid mixtures, such as a mixture of gaseous fuel and an oxygenous gas, noisy operation, roaring and whistling are produced which are annoying and undesirable. Such noises are encountered in many conventional burners which are equipped with a burner grid comprising parallel strips spaced apart to provide apertures through which the combustible mixture is projected and in front of which the combustion takes place. Such burners are generally regarded as those of the Bunsen type. The noises are more conspicuous in installations where the combustion is forced or where the fuel is used in relatively large quanity in proportion to the burner orifice, such as a burner system in which the combustion chamher is maintained during combustion at pressures below that of the surrounding atmosphere, or in general where the pressure drop across the burner grid is relatively arge.

A burner construction has now been discovered which does not produce these noises when operated in the service referred to. The novel burner grid provides a relatively large number of small orifices, a relatively large orifice area per unit area of grid and a relatively small nonorifice area. Thus relatively small burner grids are provided which are capable of handling relatively large quantities of fuel without producing annoying sounds when operated in the service referred to. One feature of the novel burner comprises a grid which may be made by flattening a double coil of wire, thereby forming a flat ribbon, and then using one or more lengths of the ribbon to form a perforate grid, or partition which is secured in place across the burner orifice in the manner that the grid of a Bunsen burner is mounted.

Accordingly one object of the present invention is to provide novel burners which are quiet in operation and have high capacity.

Other objects of the invention will become apparent from the following description which is made with reference to the drawings in which FIG. 1 is a side elevational view of a burner arrangement suitable for burning fluid combustible mixtures such as combustible mixtures of natural gas and air in which the combustion chamber is operated at sub-atmospheric pressures,

FIG. 2 is a partial cross sectional schematic view of the burner housing taken along a median plane parallel to the plane of the drawing of FIG. 1,

FIG. 3 is a partial front elevational schematic view of the burner grid support and the burner grid, illustrating one form of grid made in accordance with the invention,

FIG. 4 is an enlarged front elevational view of another form of grid,

FIG. 5 is a front elevational view of a single length of formed ribbon which may be used to form a composite grid,

FIG. 6 is a front elevational schematic view of still another form of composite burner grid and a frame within which the grid is assembled,

FIG. 7 is an end elevational view of a frame made in accordance with FIG. 6, and including a broken away portion of the burner wall wherein the grid may be mounted,

FIG. 8 is a view in perspective of a modified grid mount,

FIG. 9 is a partial enlarged cross sectional schematic view taken similarly to FIG. 2 which illustrates a manner of mounting a burner grid, such as that shown in FIG. 8, 7

FIG. 10 is an enlarged side elevational view of a section of the grid,

FIG. 11 is a schematic view partially in elevation and partly in cross section of a burner having a circular burner grid, and

FIG. 12 is a cross sectional schematic view of the burner shown in FIG. 11 taken along the line XIXI.

Referering to FIG. 1 the burner is enclosed within the burner housing 1 which is connected by the pipe 2 to a control or mixing device 3 which supplies a combustible mixture of fluid combustible and oxygenous gas to the burner through a fuel mixing chamber 4 (FIG. 2) at the rear of the burner grid 5. Gaseous combustible may be supplied to the mixing device from a source (not shown) through the pipe 6, and air or other oxygencontaining gas may be supplied to the mixing device through the pipe 7. Combustion takes place in a combustion chamber 8 (FIG. 2) in front of the grid where a means for igniting the combustible mixture, such as the electrical spark plug 9 is disposed. The walls of chamber 4 form an extension of the pipe 2 and the burner grid 5 is mounted on a suitably formed facing in the chamber wall 10 and across the burner orifice. In this case the burner grid is disposed normal to the axis of the combustion chamber 8. The burner grids may be shaped in various ways, such as flat, cylindrical, spherical or a section of the surface of any conic section to suit the needs of any special condition.

The grids of the present invention may be made by taking a double coiled wire which is a composite of two intermeshed coils, and crushing it into a fiat ribbon while urging the crushing force endwise in the direction of the axis of the coil, so that the coils will lay over each other when flattened. Then the ribbon is cut into suitable lengths. While only one length of the ribbon may in certain cases be used as the burner grid, other forms may be made by placing the lengths of ribbon side by side contiguously and with the ends even. One form of grid may be made by fastening the lengths together along their contiguous margins by any suitable means, as by welding or by lacing with a fine wire. Soldering may also be employed but welding, such as the welds 12 (FIG. 4) is a desirable means. The composite grid thus formed is self sustaining and may be sprung into a channel 15 (FIGS. 3 and 5) which is rabbeted into the margin of the burner orifice. A pair of stiffeners, such as wires 11 (FIGS. 2 and 3) may desirably be mounted across the mid-portion of the grid, in front and in back, and extended through opposite margins of the orifice. These stiffeners serve also to hold the grid in place.

Another form of composite grid is shown in FIG. 3 in which the lengths 14 of the flattened ribbon, such as that shown in FIG. 5 are sprung into the groove 15 so that the ends will be firmly engaged. In this modification the side margins of the ribbons may not necessarily be fastened together, provided the strips are contiguous to one another and fill the entire orifice, or in case filler strips 16 are mounted in the grooves, preferably one on each side of the grid element, so that the burner grid will be symmetrically placed in the burner housing. This arrangement is especially useful in that the area of the grid may be easily changed at will.

The burner grid illustrated in FIG. 6 comprises an internally grooved or channeled frame 20 for holding the lengths of ribbon. The frame 20 may desirably be formed from short lengths of channel and fastened at the corners, as by welding. Another arrangement is shown in FIG. 6 wherein the upper and lower channel members are left open at one end, and stops, such as the pins 21 are passed from front to back through the opposite sides of the channel members to hold the burner grid-forming parts in secure alignment and in place. Instead of the pins 21, the open ends of the channels may be bent inwardly to engage the end grid. This structure with its frame constitutes a unit which may be mounted across the burner orifice in a groove 15 which may be open at one end so that the framed unit may be readily removed and replaced. When the framed unit is removed the grid area may be readily altered or repaired. When pins 21 are used to retain the grid elements in the frame, the open ends of either or both channels may be sprung outwardly toengage the sides of the groove 15 for lodging the framed grid therein, but other means may be used.

FIG. 8 is illustrative of another modification in which any of the grid forms may be mounted in a frame 20, such as that shown in FIGS. 6, 8 and 9. The modification shown in FIGS. 8 and 9 is a rectangular channeled frame in which the grid elements are mounted, either individually or as a composite or unitary grid. Tabs 30 extending obliquely and outwardly from the plane of the outer side of the frame may be cut out of the wall of the channel. The burner orifice is then formed to fit the frame 2 and an inwardly projecting flange 31 on the inner side of the Wall it is provided to serve as a seating member upon which to seat the framed grid element. The framed grid is then pressed into the burner orifice until it is seated and the tabs are sprung inwardly so that the tabs terminal edges press against the inner margins of the orifice, holding the unit securely in place. Instead of cut-outs the tabs 30 may be strips of metal, or other projecting members on the frame which may be sprung inwardly toward each other when the frame is seated. The frame shown in FIG. 6 may be similarly provided with tabs or cut-outs. If desired suitable depressions, channels or notches may be formed in the orifice for engaging the outer ends of the members 30.

A grid of heat resistant material comprising a plurality of the described perforate strips or ribbons mounted contiguously along their sides forms a grid in which all the openings in the grid have curved sides. The openings 26 distributed lengthwise along the middle area of each ribbon in regular pattern are the largest, and the margins of these openings as viewed from within the same are concavo-concave, which is to say that they curve away from each other in the manner that a pair of parentheses curve. At the ends or points of the concavo-concave shaped margins are three sided openings 27 having three concave sides as referred to the longitudinal axis of the ribbon, one of which sides bulges outwardly from the axis, and two of which form a point directed toward and transversely to the axis of the ribbon. The latter two sides are in line with the points of the concavo-concave margins. Above and below each pointed end of the concavo-concave openings on both sides of the ribbon are four sided openings 23, having two meeting concave sides directed toward and transversely to the longitudinal axis of the ribbon, and two meeting concave sides meeting in a point directed away from said axis. The latter sides bulge outwardly near the margins of the ribbon. All these openings are arranged in a regular repetitive pattern which may be formed when the double coil of wire is crushed into a flat ribbon in which the coils lay over and upon each other in the manner heretofore described.

While the invention has been illustrated hereinbefore with reference principally to flat grids, curved grids may be conveniently provided by suitably curving the walls 10 which support the grid and forming in the desired manner the channels within which the grids are lodged.

This wall and channeled structure may be elongated so that the wall 10 is cylindrical and the channels are circular. When the grid is cylindrical it may be formed by fastening the ends of one or more strips of ribbon together to form a cylinder. When a plurality of ribbons are thus formed into a cylinder the sides may be securely fastened together along their touching longitudinal edges. For mounting a cylindrical grid, a chamber 4 having cylindrical walls 10 may be provided, said wall being flanged at the end to provide a circular wall 10a. In the circular wall 10a a circular retaining channel 15 is formed, in which the upper longitudinal margin of the grid or ribbon is disposed. The other longitudinal margin of the ribbon or grid is disposed in a circular channel formed near the edge of a circular disc or cap 1017 which may be spaced from the flanged end of the cylindrical wall 4 to form an orifice about the Width of the cylindrical grid. The disc and grid may be held in position by a centrally disposed bolt 20 which is threaded into a web 21 which is supported within the chamber 4 and which is attached to the inner surface of the wall 10.

Burner grids made to conform to the structures described are perfectly quiet in operation and are capable of handling extraordinarily large volumes of combustible per unit of grid area. The grids may be easily and economically made by flattening coils of heat resistant wire in the manner described, but other methods of making such perforate grids may be employed. Any kind of heat resistant wire which may be worked in the manner described may be used. Wire of about 0.030 to about 0.040 inch in diameter, formed into a double coil about one half inch in diameter is a satisfactory proportion for making a medium sized ribbon, but larger or smaller wire, or larger or smaller coils may be successfully used as the starting structure. Wire having circular cross section is satisfactory, but other cross sectional shapes may be used.

From the foregoing disclosure it will be recognized that the invention is susceptible of still other modifications without departing from the scope and spirit thereof, and it is to be understood that the invention is not restricted to the specific illustrations herein set forth, except in so far as they are specifically limited by the terms of the appended claims.

This is a continuation-in-part of my application serial No. 831,327, filed Aug. 3, 1959, now Patent No. 3,115,- 302.

I claim:

1. A burner assembly comprising a burner housing having a combustion chamber and a fuel mixing chamber therein; a partition between said chambers having a burner orifice therein; a perforate burner grid disposed across said orifice; said mixing chamber conducting a supply of fluid combustible mixture to said grid; means for marginally securing said grid in place for partitioning said combustion chamber from said fuel mixing chamber; said grid comprising a perforate ribbon of heat resistant material formed by flattening two interlaced wire coils; said ribbon having openings distributed lengthwise along its middle area in regular pattern, the margins of said openings being concave-concave and the axis through the pointed ends thereof being disposed transverse to the longitudinal axis of the ribbon; openings at the pointed ends of said margins which have three sided margins, two sides of which are convex and meet in a point directed transversely to said longitudinal axis and in line with the points of said concavo-concave margins, the third side of said three sided openings being convex and bulging away from said axis; and a plurality of four sided openings above and below each point of the margins of said concavo-concave openings, said four sided openings having two meeting concave margins bulging outwardly from said longitudinal axis and two convex margins forming a point which is directed inwardly and transverse to said longitudinal axis, all of said openings being arranged in a regular repetitive pattern throughout the length of said ribbon.

2. A device in accordance with claim 1 in which the burner grid comprises a plurality of said ribbons assembled contiguously side by side.

3. A device in accordance with claim 1 in which the burner grid comprises a plurality of said ribbons assembled contiguously side by side; and means for securing the ribbons in place.

4. A device in accordance with claim 1 which comprises a plurality of said ribbons assembled contiguously side by side; and means for fastening said contiguous sides together.

5. A device in accordance with claim 1 in which the burner grid comprises a plurality of ribbons assembled side by side; said means for marginally securing said grid in place, a channeled frame in which the channel opens inwardly, said ribbons being assembled with their ends disposed in said channeled frame.

6. A device in accordance with claim 5 in which the frame is mounted within said burner orifice; and means for securing the frame in place.

7. A device in accordance with claim 1 in which the grid is cylindrical and is secured in place by clamping opposite longitudinal sides thereof in circular grooves, one of said grooves being formed in the chamber wall and the other being formed near the edge of a circular disc which is spaced from the wall of the chamber.

References Cited in the file of this patent UNITED STATES PATENTS 731,384 Newbold June 16, 1903 2,336,816 Thompson Dec. 14, 1943 2,435,391 Gunderman Feb. 3, 1948 2,644,946 Menz et al. July 14, 1953

Claims

1. A BURNER ASSEMBLY COMPRISING A BURNER HOUSING HAVING A COMBUSTION CHAMBER AND A FUEL MIXING CHAMBER THEREIN; A PARTITION BETWEEN SAID CHAMBERS HAVING A BURNER ORIFICE THEREIN; A PERFORATE BURNER GRID DISPOSED ACROSS SAID ORIFICE; SAID MIXING CHAMBER CONDUCTING A SUPPLY OF FLUID COMBUSTIBLE MIXTURE TO SAID GRID; MEANS FOR MARGINALLY SECURING SAID GRID IN PLACE FOR PARTITIONING SAID COMBUSTION CHAMBER FROM SAID FUEL MIXING CHAMBER; SAID GRID COMPRISING A PERFORATE RIBBON OF HEAT RESISTANT MATERIAL FORMED BY FLATTENING TWO INTERLACED WIRE COILS; SAID RIBBON HAVING OPENINGS DISTRIBUTED LENGTHWISE ALONG ITS MIDDLE AREA IN REGULAR PATTERN, THE MARGINS OF SAID OPENINGS BEING CONCAVO-CONCAVE AND THE AXIS THROUGH THE POINTED ENDS THEREOF BEING DISPOSED TRANSVERSE TO THE LONGITUDINAL AXIS OF THE RIBBON; OPENINGS AT THE POINTED ENDS OF SAID MARGINS WHICH HAVE THREE SIDED MARGINS, TWO SIDES OF WHICH ARE CONVEX AND MEET IN A POINT DIRECTED TRANSVERSELY TO SAID LONGITUDINAL AXIS AND IN LINE WITH THE POINTS OF SAID CONCAVO-CONCAVE MARGINS, THE THIRD SIDE OF SAID THREE SIDED OPENINGS BEING CONVEX AND BULGING AWAY FROM SAID AXIS; AND A PLURALITY OF FOUR SIDED OPENINGS ABOVE AND BELOW EACH POINT OF THE MARGINS OF SAID CONCAVO-CONCAVE OPENINGS, SAID FOUR SIDED OPENINGS HAVING TWO MEETING CONCAVE MARGINS BULGING OUTWARDLY FROM SAID LONGITUDINAL AXIS AND TWO CONVEX MARGINS FORMING A POINT WHICH IS DIRECTED INWARDLY AND TRANSVERSE TO SAID LONGITUDINAL AXIS, ALL OF SAID OPENINGS BEING ARRANGED IN A REGULAR REPETITIVE PATTERN THROUGHOUT THE LENGTH OF SAID RIBBON.