JP2000097409A - Burner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make uniform the flame length at each flame hole during combustion by projecting a protrusion inward from the wall constituting a mixing chamber. SOLUTION: Burner head 11 comprises an annular outer circumferential wall 11b on the bottom part thereof, and an annular rib 11c projecting upward from the inner circumferential part of the bottom. A tubular burner ring 2 having a large number of flame holes 2a are fitted in the rib 11c and protrusions 51, 52, 53 are projected inward from the outer circumferential wall 11b of a mixing chamber S facing the flame hole 2a of the burner ring 2. A guide face 51a, 52a, 53a for inclining the flow of mixed gas by a specified angle to the flame hole 2a side is provided at an upstream part of each protrusion 51, 52, 53. According to the arrangement, flame length at each flame hole can be made uniform during combustion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air-fuel mixture chamber extending in a passage shape and a mixing pipe for feeding the air-fuel mixture into the air-fuel mixture chamber so that the air-fuel mixture flows in the air-fuel mixture chamber in one direction. And
The present invention relates to a burner in which a large number of flame holes are formed in a wall constituting a mixture chamber.

[0002]

2. Description of the Related Art A burner of this type includes an annular air-fuel mixture chamber, and a mixing pipe is connected from the tangential direction of the air-fuel mixture chamber. There is a burner. In the burner having such a configuration, the air-fuel mixture supplied from the mixing pipe to the air-fuel mixture chamber flows in a certain direction so as to circulate through the annular air-fuel mixture chamber, and is gradually ejected from each of the flame holes. Becomes smaller toward the downstream side in the flow direction. Therefore, when the cross-sectional area of the flow path of the annular air-fuel mixture chamber is made constant over the entire circumference, there is a case where the gas static pressure increases toward the downstream side and the gas ejection amount increases.

In such a case, conventionally, the gas cross-sectional area of the air-fuel mixture chamber is made smaller toward the downstream side so that the gas static pressure is kept uniform, the gas ejection amount is made uniform, and the flame holes at the time of combustion are reduced. The flame length is uniform.

[0004]

By the way, if the flow path cross-sectional area of the air-fuel mixture chamber becomes narrower toward the downstream side in the gas flow direction,
At the most downstream part, the cross-sectional area of the flow passage becomes extremely narrow. Therefore,
Even if the air-fuel mixture chamber is formed with a predetermined processing accuracy, the rate of change in the flow path cross-sectional area due to the processing becomes relatively large toward the downstream side where the flow path cross-sectional area is small, and the desired flow path disconnection is stable. It becomes difficult to obtain an area. If the desired flow path cross-sectional area is not obtained, the desired gas static pressure cannot be obtained, and therefore, the amount of gas jet at the downstream flame hole cannot be adjusted to the desired amount, and the length of the flame at each flame hole is reduced. Cannot be uniform.

[0005] In view of the above problems, the present invention provides a burner in which the flame length in each flame hole during combustion is made uniform without reducing the cross-sectional area of the flow passage toward the downstream side of the air-fuel mixture chamber. The task is to provide.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a mixture chamber extending in the shape of a passage and a flow of the mixture in the mixture chamber in one direction. A mixing pipe for feeding the mixture into the mixture chamber, and a burner in which a number of flame holes are formed in a wall constituting the mixture chamber; The length of the flame in each flame hole at the time of combustion is made uniform.

When a projection is provided in the mixture chamber, the static pressure of the air-fuel mixture on the upstream side of the projection increases, so that the amount of air-fuel mixture jetted on the upstream side of the projection increases compared to the case where no projection is provided. The length of the flame in the flame hole becomes longer. Therefore, it is possible to reduce the difference in the gas ejection amount between the upstream portion and the downstream portion of the air-fuel mixture chamber without narrowing the cross-sectional area of the flow passage toward the downstream side, and to make the length of the flame in the flame hole uniform during combustion. . Further, in the conventional one in which the flow path cross-sectional area is narrowed toward the downstream, high processing accuracy is required downstream of the air-fuel mixture chamber. Easy.

Further, if a plurality of the protrusions are provided at intervals in the gas flow direction of the gas mixture chamber, the difference in the amount of gas mixture ejected between the most upstream part and the most downstream part of the gas mixture chamber can be reduced. Can,
The flame length at the flame hole at the time of combustion becomes more uniform.

Since the gas flow rate is smaller in the downstream direction of the gas flow, the projection of the protrusion into the air-fuel mixture chamber at a position downstream of the flow direction of the air-fuel mixture is larger. This is preferable for achieving uniform length.

[0010] By the way, if a projection protruding into the air-fuel mixture chamber is provided, a constricted portion having a small flow path cross-sectional area is partially formed in the air-fuel mixture chamber. Becomes lower. Therefore, there is a possibility that the amount of air-fuel mixture ejected from the flame hole close to the protrusion may be reduced as compared to the amount of gas ejected from the flame hole on the upstream side or downstream side of the protrusion, but the protrusion is located at a position facing the flame hole. If provided, a guide surface that inclines the direction of flow of the air-fuel mixture toward the flame hole side by a predetermined angle allows the air-fuel mixture to be ejected from the flame hole using the dynamic pressure of the air-fuel mixture,
A decrease in the amount of air-fuel mixture ejected from the flame hole close to the projection is prevented, and the flame length in the flame hole is prevented from becoming uneven.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, reference numeral 1 denotes a burner body of a burner, which has an annular burner head 11 and a mixing pipe 12 connected to the burner head 11. The burner head 11 includes an annular outer peripheral wall 11b provided on the outer peripheral side of the bottom portion 11a, and an annular rib 11c formed on the inner peripheral portion of the bottom portion 11a so as to protrude upward. The rib 1
A cylindrical burner ring 2 having a large number of flame holes 2a,... Is fitted on the inner periphery of 1c, and an annular burner cap 3 extending over both of them is mounted on the burner body 1 and the burner ring 2. Is placed. The burner ring 2 is formed with a number of slit-shaped flame holes 2a,. The burner cap 3 is in airtight contact with the upper end of the burner ring 2 on the lower surface 3a on the inner peripheral side, and is fitted on the outer peripheral wall 3b in an airtight manner with the upper end of the outer peripheral wall 11b of the burner head 11. That is, the burner head 11, the burner ring 2, and the burner cap 3 are walls that constitute a mixture chamber S extending in an annular passage shape.
The air-fuel mixture chamber S has a constant cross-sectional area from the upstream end Sj to the downstream end Sk (that is, the area of the cross-section orthogonal to the tangent to the curve indicating the flow direction F of the air-fuel mixture) without being reduced.

One end of the mixing pipe 12 is connected to the burner head 11 and communicates with the air-fuel mixture chamber S. The mixing pipe 12 is connected to a fuel gas ejected from a nozzle 4 inserted into an intake port 12a formed at the other end. An air-fuel mixture with air sucked from the surroundings is sent into the air-fuel mixture chamber S. In the communication part between the mixing pipe 12 and the burner head 11, the mixing pipe 12 is directed in the extending direction of the passage-shaped mixture chamber S, that is, in the circumferential direction of the ring, and the communication part is provided with a partition wall 12b. ing. The air-fuel mixture sent from the mixing pipe 12 into the air-fuel mixture chamber S is supplied to the upstream end Sj of the air-fuel mixture chamber S.
From one side to the downstream end Sk in one direction (the direction of arrow F). In addition, in this embodiment, the partition wall 12b is the rib 1
1c, the downstream end Sj of the air-fuel mixture chamber S joins the upstream end Sk, but the partition wall 12a is formed to extend in the flow direction, and the air-fuel mixture It flows in one direction.

The outer peripheral wall 11b of the burner head 11
Include protrusions 51, 52,
53 are provided. Since the air-fuel mixture flow rate in the air-fuel mixture chamber S decreases downstream, if the cross-sectional area of the flow path is constant, the flow velocity decreases toward the downstream, so that the static pressure of the air-fuel mixture increases and the ejection amount increases. As the length of the flame increases, the length of the flame of the entire burner varies. In this regard, if the protrusions 51, 52, and 53 are provided as in the present embodiment, it becomes difficult for the air-fuel mixture to flow downstream of the protrusions 51, 52, and 53.
The static pressure of the air-fuel mixture on the upstream side of 53 rises and protrusions 51 and 5
The ratio of the amount of air-fuel mixture ejected from the upstream flame holes 2a, 253 increases, and the flame length is made uniform over the entire burner. In other words, if the projections 51, 52, 53 are provided, the difference in the amount of gas mixture injected from each of the flame holes 2a,... The length of the flame in each of the flame holes 2a,... Can be made uniform.

By improving the processing accuracy only at the projections 51, 52, and 53, the amount of air-fuel mixture jetted from each of the flame holes 2a,... Can be adjusted to a desired amount. Easy.

The position of the projections 51, 52, 53 may be the bottom 11a of the burner head 11 or the inside of the mixture chamber S as long as the static pressure of the mixture at the upstream side can be increased. It may be a wall surface on which a peripheral flame hole is formed. Accordingly, for example, as shown in FIG. 3, the burner ring 2 may be provided with protrusions 51, 52, 53 toward the outer peripheral side. Note that the same components as those described above are denoted by the same reference numerals and description thereof is omitted.

By the way, the projections 51, 5 are provided in the air-fuel mixture chamber S.
By providing the gas turbines 2 and 53, a constricted portion A having a partially narrowed flow passage cross-sectional area is formed in the air-fuel mixture chamber S, the flow rate of the air-fuel mixture in this portion is increased, and the static pressure is reduced. Therefore, the protrusions 51,
The amount of air-fuel mixture ejected from the flame holes 2a,... Close to 52, 53 is the upstream or downstream side of the protrusions 51, 52, 53.
And the flame length during combustion becomes shorter. Therefore, in the present embodiment, the projections 51, 52, and 53 protruding into the mixture chamber S are provided on the outer peripheral wall 11b of the mixture chamber S facing the flame holes 2a,. The guide surface 51a, which inclines the flow direction of the air-fuel mixture toward the flame holes 2a,.
52a and 53a were provided.

In the present embodiment, the guide surface 5 has an ascending gradient toward the downstream side in the flow direction of the air-fuel mixture.
The inclination angles of 1a, 52a, and 53a were set to 45 degrees with respect to the tangent of the outer peripheral wall 11b. In this manner, the air-fuel mixture can flow toward the flame holes 2a,... Of the constriction A, and the corresponding flame holes 2a,.
Can be prevented from decreasing the amount of gas mixture blown out, and the flame lengths at the flame holes 2a,. Also, protrusion 5
Downstream portions of 1, 52, and 53 are provided with inclined surfaces 51b, 52b, and 53b having a downward slope toward the downstream side in the flow direction of the air-fuel mixture to prevent turbulence such as a vortex. In addition,
The inclination angles of these inclined surfaces 51b, 52b, 53b are 45 degrees with respect to the tangent. Therefore, the projections 51, 52, and 53 of the present embodiment have a mountain shape that tapers toward the tip. In addition, if a plurality of projections, in this embodiment, three projections 51, 52, 53 are provided at intervals in the direction in which the passage-shaped mixture chamber S extends, each flame hole 2a is provided as compared with the case where one projection is provided. ,.. Can be more uniform, and the flame length during combustion can be uniform.

Further, since the flow rate of the mixture in the mixture chamber S decreases toward the downstream, when the plurality of projections 51, 52, 53 are provided, the flow path of the mixture S in the downstream direction in the extending direction of the mixture chamber S is increased. The projecting amount is larger for the projection, so that the flow path cross-sectional area of the constricted portion A becomes smaller toward the downstream side. In the present embodiment, the dimensions of the air-fuel mixture chamber S are the values shown in FIG.
The protrusion amount of the intermediate protrusion 52 was 8 mm, and the protrusion amount of the most downstream protrusion 53 was 12 mm. Each projection 51,
In order to show the difference between the protrusion amounts of the protrusions 52 and 53, in addition to the front end position 51t of the protrusion 51 on the most upstream side in FIG. Position 53t is shown. In this way, even in the downstream where the flow rate is small, the static pressure of the air-fuel mixture on the upstream side can be increased by the projection, and the amount of the air-fuel mixture jetted out of each of the flame holes 2a,. Can be made uniform in length. The width of the tip of each of the projections 51, 52, 53 in the flow direction is common to 3 mm.

Further, in the above embodiment, the annular air-fuel mixture chamber S of the burner is constituted by the burner head 11, the burner ring 2 and the burner cap 3, but corresponding parts are integrally constituted. The present invention can be similarly applied to a case where an air-fuel mixture chamber is formed inside a burner. Furthermore, although the internal flame type burner has been described as an example, the present invention can be similarly applied to an external flame type burner having a flame hole facing outward, and a burner having a flame hole facing upward.

[0020]

As described above, according to the present invention, the length of the flame in each flame hole can be made uniform without reducing the cross-sectional area of the flow passage toward the downstream side of the mixture chamber. Further, if it is not necessary to reduce the flow path cross-sectional area toward the downstream side, there is no portion where the processing accuracy is relatively reduced, and it becomes easy to secure the flow path cross-sectional area at any place in the air-fuel mixture chamber.

[Brief description of the drawings]

FIG. 1 is a plan view showing a burner according to the present invention.

FIG. 2 is a side view, partially broken away, showing a burner according to the invention;

FIG. 3 is a plan view showing a burner according to another embodiment.

FIG. 4 is a cross-sectional view showing dimensions of an air-fuel mixture chamber.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Burner body 11 Burner head 12 Mixing pipe 2 Burner ring 2a Flame hole 3 Burner cap 51,52,53 Projection 51a, 52a, 53a Guide surface A Narrow part S Mixed air chamber

 ──────────────────────────────────────────────────続 き Continuation of the front page (71) Applicant 000115854 Rinnai Corporation 2-26, Fukuzumicho, Nakagawa-ku, Nagoya-shi, Aichi (72) Inventor Toshinari Momose 4-1-2, Hiranocho, Chuo-ku, Osaka-shi, Osaka Osaka Within Gas Co., Ltd. (72) Inventor Toshimichi Obara 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka Osaka Gas Co., Ltd. (72) Inventor Nobuo Ohtake 1-5-2, Kaigan, Minato-ku, Tokyo Tokyo Gas Inside (72) Inventor Masao Takagi 19-18 Sakuradacho, Atsuta-ku, Nagoya City, Aichi Prefecture Inside (81) Inventor Masafumi Matsubara 19-18 Sakuradacho, Atsuta-ku, Nagoya City, Aichi Prefecture Toho Kunigas Incorporated (72) Inventor Yasunobu Takemoto 2-26, Fukuzumi-cho, Nakagawa-ku, Nagoya-shi, Aichi F-term (in reference) 3K017 AA10 AB07 AC02 AD07 AD11 AD14

Claims (4)

[Claims] An air conditioner comprising: a mixture chamber that extends in a passage form; and a mixing pipe that feeds the mixture into the mixture chamber such that a flow of the mixture in the mixture chamber is unidirectional. In a burner in which a number of flame holes are formed in a wall constituting an air chamber,
A burner characterized in that a protrusion protruding into the air-fuel mixture chamber is provided to make the length of the flame in each of the flame holes during combustion uniform. 2. The burner according to claim 1, wherein a plurality of the protrusions are provided at intervals in a gas flow direction of the mixture chamber. 3. The burner according to claim 2, wherein an amount of the protrusion that protrudes into the air-fuel mixture chamber becomes larger as the protrusion is located further downstream in the flow direction of the air-fuel mixture. 4. The projection according to claim 1, wherein the projection is provided at a position facing the flame hole, and has a guide surface for inclining a flow direction of the air-fuel mixture to the flame hole side at a predetermined angle.
The burner according to any one of claims 1 to 3.