BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to a heating device, and more particularly to a burner, which could fully mix gas and air for a more even burning performance.
2. Description of Related Art
A conventional burner 1 is illustrated in FIG. 1, including a base 2 and a combustion tray 3. The base 2 is formed by two symmetrical panels which are made by stamping, wherein each of the panels is designed to have a specific shape, so that the base 2 has a U-shaped inlet pipe 2a horizontally formed therein. One end of the inlet pipe 2a is an inlet 2b adapted to accept gas and air. The combustion tray 3 is long in shape, and is provided above the base 2. A plurality of flame vents 3a are provided on the combustion tray 3. The flame vents 3a are arranged in a longitudinal direction of the combustion tray 3, and communicate with the inlet pipe 2a. By igniting the mixed gas and air which passes through the inlet pipe 2a and flows out through the flame vents 3a of the combustion tray 3, flames can be created.
However, the inlet pipe 2a of the base 2 has a turn in it, and gradually becomes narrower after passing the turn. Therefore, most of the airflow in the inlet pipe 2a turns left after bumping into the turning section, and then tends to flow out through the flame vents 3a on the left side of the combustion tray 3. As a result, the amount of the mixed gas and air flowing out from the flame vents 3a gradually decreases from left to right.
The relationship between the mass flow and the position of each of the flame vents 3a is illustrated in FIG. 2, wherein the flame vents 3a are numbered as 01-44 from left to right in sequence. It can be clearly seen that the mass flow of the flame vents 3a decreases from left to right obviously. In other words, the flame vents 3a with lower mass flow (such as the flame vent #34) would have smaller flame comparing to the flame vents 3a with higher mass flow (such as the flame vent #04). Therefore, the flame created by the burner 1 shows a gradual decrease from left to right, leading to an uneven heating performance, which reduces the heating efficiency.
BRIEF SUMMARY OF THE INVENTION
In view of the above, the primary objective of the present invention is to provide a burner, which could send out the airflow through the flame vents of the combustion tray in a more even way.
To achieve the objective of the present invention, the present invention provides a burner, which includes a base and a combustion tray. The base includes an inlet pipe and two horn-shaped tubes, wherein each of which has a first section and a second section connected to the first section in a substantially perpendicular manner. Each of the first sections is connected to the inlet pipe. A length of each of the first sections is greater than or equal to an inner diameter of the inlet pipe at where the first sections are connected to. Each of the second sections is bent to extend toward the other second section, and communicates with at least one air passage, wherein the air passage which communicates with one of the second sections also communicates with the air passage which communicates with the other one of the second sections. The combustion tray is provided on the base, wherein the combustion tray includes a flame plate located above the air passages communicating with the second sections of the horn-shaped tubes. The flame plate has a plurality of first flame vents communicating with the air passages.
With the aforementioned design, the symmetrical horn-shaped tubes could direct the airflow to the combustion tray, wherein the airflow would pass through the flame vents in a more even distributed manner, whereby to provide a more even heating performance as well. Furthermore, since the length of each of the first sections is greater than or equal to the inner diameter of the inlet pipe at where between the horn-shaped tubes, gas and air could be mixed more evenly, enhancing the heating efficiency.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The present invention will be best understood by referring to the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which
FIG. 1 is a perspective view of a conventional burner;
FIG. 2 is a relationship chart, showing the relationship between the mass flow and the positions of the flame vents of the conventional burner;
FIG. 3 is a perspective view of a first embodiment of the present invention;
FIG. 4 is a sectional view along the 4-4 line in FIG. 3;
FIG. 5 is a partial sectional perspective view, showing parts of the first embodiment;
FIG. 6 is a sectional view along the 6-6 line in FIG. 3;
FIG. 7 is a partial sectional perspective view, showing part of the structure of the flow splitter;
FIG. 8 is a relationship chart, showing the relationship between the mass flow and the positions of the flame vents of the first embodiment, in comparison with the relationship between the mass flow and the positions of the flame vents of the conventional burner;
FIG. 9 is a perspective view of a second embodiment of the present invention;
FIG. 10 is a partial sectional perspective view of FIG. 9;
FIG. 11 is a partial sectional view of a third embodiment of the present invention; and
FIG. 12 is a partial sectional view of a fourth embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
A burner 100 of a first embodiment of the present invention is illustrated in FIG. 3 to FIG. 5, including a base 10, a combustion tray 20, and a flow splitter 30.
The base 10 is formed by two symmetrical panels 10a, which are made by stamping, and are designed to have a specific shape so that the base has an inlet pipe 12 and two horn-shaped tubes 14 formed therein. The inlet pipe 12 has an inlet end 122 and a closed end 124, wherein the inlet end 122 is adapted to accept gas and air. The inlet pipe 12 has a curved surface 124a recessed into an inner wall of the closed end 124, wherein the curved surface 124a recesses in a direction opposite to the inlet end 122. The curved surface 124a would be helpful to mix gas and air more evenly. In addition, a reduced section 126 is provided between the inlet end 122 and the closed end 124 of the inlet pipe 12, wherein an inner diameter of the reduced section 126 is less than an inner diameter of anywhere else of the inlet pipe 12. In other words, the reduced section 126 is the narrowest section of the inlet pipe 12. The inlet pipe 12 further has two lateral openings 128 located between the closed end 124 and the reduced section 126, wherein each of the lateral openings 128 respectively communicates with one of the horn-shaped tubes 14.
Each of the horn-shaped tubes 14 respectively has a first section 142 and a second section 144, wherein the first section 142 is connected to the inlet pipe 12, and communicates with one of the lateral openings 128, while the second section 144 is connected to the first section 142 in a direction substantially perpendicular to the first section 142. A length of the first section 142 is greater than or equal to the inner diameter of the inlet pipe 12 at where between the horn-shaped tubes 14 (i.e., the width w shown in FIG. 2). In other words, the length of the first section 142 is greater than or equal to the distance between the lateral openings 128. Each of the second sections 144 is bent to extend toward the other second section 144, and communicates with at least one air passage 144a, wherein the air passage 144a communicating with one of the second sections 144 also communicates with the air passage 144a communicating with the other one of the second sections 144. As shown in FIG. 5, each of the first sections 142 respectively has an indented section 142a, wherein a cross-sectional area thereof is 70 percent to 80 percent of an average cross-sectional area of other portions of the first section 142. More specifically, the cross-sectional area of each of the indented sections 142a is a minimum cross-sectional area in the corresponding first section 142. In the first embodiment, each of the indented sections 142a is realized by providing a projecting ring 16 inside the corresponding first section 142, wherein an area surrounded by an inner peripheral surface 16a of each of the projecting rings 16 is the minimum cross-sectional area of the corresponding first section 142.
The combustion tray 20 is long in shape, and is provided on the base 10, wherein the combustion tray 20 includes a flame plate 22 located above the air passages 144a communicating with the second sections 144 of the horn-shaped tubes 14. The flame plate 22 has a plurality of first flame vents 22a arranged in a longitudinal direction of the combustion tray 20, wherein the first flame vents 22a communicate with the air passages 144a. Each of two lateral sides of the combustion tray 20 is formed by connecting a lateral plate 24 and an inclined plate 26, as illustrated in FIG. 6. The flame plate 22 of the combustion tray 20, the lateral plates 24, and the inclined plates 26 surround a chamber S. Each of the inclined plates 26 is engaged with a peripheral edge of one of the air passages 144a, wherein a distance between the inclined plates 26 gradually increases in a direction from the air passages 144a toward the lateral plates 24. The flame plate 22 further includes a plurality of second flame vents 22b evenly and correspondingly distributed on two opposite sides of the row of the first flame vents 22a, wherein the second flame vents 22b also communicate with the air passages 144a. In practice, the second flame vents 22b could be arranged on two sides of the row of the first flame vents 22a in a staggered way.
As shown in FIG. 6 and FIG. 7, the flow splitter 30 is provided in the combustion tray 20 (i.e., located in the chamber S), wherein the flow splitter 30 includes two panels 32. Each of the panels 32 includes a bottom portion 32a and two lateral portions 32b. For each of the panels 32, the bottom portion 32a has a plurality of bores 322a provided thereon, and the lateral portions 32b are respectively connected to two lateral edges of the bottom portion 32a to substantially form a U-shape structure. One of the lateral portions 32b of one of the panels 32 is adjacent to one of the lateral portions 32b of the other one of the panels 32. A channel 34 is formed between said adjacent panels 32, wherein the channel 34 communicates with the bores 322a, the first flame vents 24, and the air passages 144a communicating with the second sections 144. The other one of the lateral portions 32b of each of the panels 32 respectively abuts against one of the lateral plates 24. The flow splitter 30 includes at least one connecting plate 36. In the first embodiment, the at least one connecting plate 36 includes a plurality of connecting plates 36 arranged at regular intervals in a longitudinal direction of the flow splitter 30, and each of the connecting plates 36 is connected to said adjacent lateral portions 32b.
With the aforementioned design, airflow containing gas and air could enter the burner through the inlet end 122. Since a cross-sectional area of the inlet pipe 12 first reduces toward the reduced section 126 and then increases, a velocity of the airflow would be increased while passing through the reduced section 126. Turbulence would be created once the airflow bumps into the closed end 124, which could further mix the gas and air before the airflow enters the first sections 142 through the lateral openings 128. Because the length of each of the first sections 142 is greater than or equal to the distance between the lateral openings 128 of the inlet pipe 12, there would be a sufficient distance to even further mix the gas and air. In addition, while the airflow is passing through the indented section 142a along a tube wall of each of the first sections 142 and hitting the corresponding projecting ring 16, turbulence would be also created around where the projecting ring 16 is, whereby to mix the gas and air again. After that, the airflow in each of the horn-shaped tubes 14 would pass through the projecting ring 16, the second section 144, the air passage 144a, and the flow splitter 30 in sequence, and then would be exhausted through the first flame vents 22a and the second flame vents 22b.
A relationship between the mass flow and the positions of the first flame vents 22a of the burner 100 of the first embodiment is illustrated in FIG. 8, in comparison with the relationship between the mass flow and the positions of the flame vents 3a of the aforementioned conventional burner 1. The first flame vents 22a are numbered as 01-44 from left to right in sequence. A mass flow of airflow outputted from the first flame vents 22a of the burner 100 of the first embodiment (i.e., the dotted line shown in FIG. 8) distributes more evenly than that of the flame vents 3a of the conventional burner 1 (i.e., the solid line shown in FIG. 8). Therefore, the flame generated by the first flame vents 22a of the burner 100 of the first embodiment would be more even, and the heating efficiency could be enhanced as a result.
A burner 200 of a second embodiment of the present invention is illustrated in FIG. 9 and FIG. 10, which has almost the same structure as the aforementioned first embodiment, except that an indented section 42 of each of first sections 40 of the second embodiment is formed by stamping. Furthermore, the base 44 is integrally made. Whereby, the burner 200 could be easily manufactured and assembled.
A burner 300 of a third embodiment of the present invention is illustrated in FIG. 11, which has almost the same structure as the aforementioned first embodiment, except that the burner 300 further includes a metal mesh 46, which has a plurality of meshes. A flame plate 50 of a combustion tray 48 of the third embodiment has an inner surface 50a and an outer surface 50b, wherein first flame vents 502 and second flame vents 504 all go through the inner surface 50a and the outer surface 50b. The metal mesh 46 abuts against the inner surface 50a. A range of a projection of each of the first flame vents 502 and each of the second flame vents 504 covers a plurality of the meshes. A maximum diameter of the meshes of the metal mesh 32 is less than a minimum width of each of the first flame vents 502 and each of the second flame vents 504. The metal mesh 46 could regulate the airflow, making the flame which comes out from the first flame vents 502 and the second flame vents 504 become more even, whereby to prevent the flame created through the first flame vents 502 and the second flame vents 504 from splitting as resembling a fork.
A burner 400 of a fourth embodiment of the present invention is illustrated in FIG. 12, which has almost the same structure as the aforementioned second embodiment, except that a flame plate 54 of a combustion tray 52 of the fourth embodiment has a middle blocking portion 542 extending in a longitudinal direction of the combustion tray 52. The flame plate 54 of the combustion tray 52 bulges outward from an inner surface 54a toward an outer surface 54b thereof. A metal mesh 56 abuts against the inner surface 54a. In the fourth embodiment, each first flame vent 544 and each second flame vent 546 have the same size, wherein the first flame vents 544 and the second flame vents 546 are respectively located on two lateral sides of the middle blocking portion 542 in a transverse direction of the combustion tray 52. The first flame vents 544 and the second flame vents 546 are respectively arranged in the longitudinal direction of the combustion tray 52. In the fourth embodiment, a channel 582 of the flow splitter 58 is located directly below the middle blocking portion 542, and bores 584 of the flow splitter 58 are respectively located directly below the first flame vents 544 and the second flame vents 546. Whereby, the flame could be distributed on two lateral sides of the middle blocking portion 542, which spreads the flame of the whole combustion tray 52 outward in the transverse direction thereof. In practice, if the evenness of the flame coming out from the first flame vents 544 and the second flame vents 546 is taken out of consideration, then the metal mesh 56 could be omitted. In addition, the flame plate 54 could be designed as the shape shown in FIG. 11, which does not bulge outward.
In conclusion, the channels of each burner provided in the present invention are symmetrical, which transmits the airflow to the combustion tray in a more even way, whereby to generate a more uniform flame pattern. Furthermore, since the length of each of the first sections is greater than or equal to the distance between the lateral openings of the inlet pipe, gas and air could be mixed more evenly. In addition, the curved surface of the closed end of the inlet pipe and the indented section of each of the first sections would also facilitate the mixing of air and gas, whereby to enhance the heating efficiency.
It must be pointed out that the embodiments described above are only some preferred embodiments of the present invention. All equivalent structures which employ the concepts disclosed in this specification and the appended claims should fall within the scope of the present invention.
Patent Grant
10352557
