JPH07190358A - Ignition device - Google Patents

Abstract

PURPOSE:To improve an ignition performance in an ignition device for a gas burner in which first flame holes with low gas concentration and second flame holes with low gas concentration are alternatively arranged in parallel. CONSTITUTION:A configuration of a flame hole part having many flame holes formed therein is made such that first flame holes H1 are arranged at end edges of the flame hole part. An electrode plate T is arranged above a flame hole part B2 along outer side edges of the first flame holes H1 at the end edges of the flame hole part, an electrode part P1 of an ignition plug P is arranged above second flame holes H2 subsequent to an inside area of each of the first flame holes H1 and then electrical discharging is carried out at the electrode plate T from the electrode part P1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a light and shade burner, that is,
A gas burner of a so-called rich and lean combustion type as a whole by making a mixture of a gas mixture ejected from a flame hole part having a high gas concentration part and a low gas concentration part, in particular, an ignition device thereof. is there.

[0002]

2. Description of the Related Art In recent hot water heaters and the like, the amount of combustion has increased, and the problem of NOX in the gas burner has been highlighted. Therefore, in order to solve this problem, recently, a method of performing lean burn, that is, burning under conditions of low gas concentration has been adopted. Generally, when the gas concentration is low, the flame formed in the flame hole is likely to lift. Therefore, in order to ensure combustion stability by preventing this lifting, a gas burner, a so-called light and dark burner, in which a flame hole portion having a high gas concentration and a flame hole portion having a low gas concentration coexist is proposed. This is to secure the stable combustion of the entire flame hole by holding the unstable flame formed in the flame hole with low gas concentration by the stable flame formed in the flame hole with high gas concentration. is there.

On the other hand, a recent gas burner ignition device is
The direct ignition system by spark is adopted. Due to this, at the time of ignition, if the gas concentration is low, the ignition performance is extremely reduced. In the case of the above-mentioned rich / lean burner for realizing the lean combustion as described above, sufficient ignition performance cannot be ensured simply by making the discharge electrode of the spark ignition device correspond to the flame hole portion.

The present invention has been made in view of the above point, and "a first flame hole (H ₁ ) having a high gas concentration and a second flame hole (H ₂ ) having a low gas concentration are formed in the flame hole portion. It is an object of the present invention to improve the ignition performance in an "ignition device for gas burners alternately arranged in parallel".

[0005]

[Technical Means] The technical means of the present invention for solving the above-mentioned problem is that "a first flame hole (H ₁ ) is provided at the edge of the flame hole portion with the structure of the flame hole portion having a large number of flame holes. The electrode plate (T) is arranged above the flame hole (B ₂ ) along the outer edge of the first flame hole (H ₁ ) at the edge of the flame hole, and the first flame is arranged. Second inside the hole (H ₁ )
Provide the electrode part (P ₁ ) of the spark plug (P) above the flame hole (H ₂ ),
It was designed to discharge from the electrode part (P ₁ ) to the electrode plate (T). ”
That is.

[0006]

The above technical means operates as follows. Flame hole
At (B ₂ ), a gas mixture with a high gas concentration is ejected from the first flame hole (H ₁ ) at its edge, and a gas mixture with a low gas concentration is ejected from the inner second flame hole (H ₂ ). To do. And this second flame hole (H ₂ )
The electrode portion (P ₁ ) is located above the electrode, and at the time of ignition, the discharge path for the air-fuel mixture ejected from these flame hole groups is a path from a portion having a low gas concentration to a portion having a high gas concentration. Therefore, at the time of ignition discharge, the discharge passes through the proper ignition concentration range that is always present in any of the paths, and good ignition is performed.

After ignition, the stable flame formed in the first flame hole (H ₁ ) holds the flame in the second flame hole (H ₂ ) stably, and the entire flame hole portion (B ₂ ) The flame that spreads over is maintained in a stable combustion state.

[0008]

[Effect] Since the proper ignition concentration range exists in any of the ignition discharge paths, the ignition performance is improved. Since the gas concentration is high, the flame at the time of ignition is first formed in the first flame hole (H ₁ ) where the flame is stable, so that the flame formed in the entire flame hole portion (B ₂ ) immediately after ignition is also stable. That is, the combustion immediately after ignition is stable.

[0009]

Embodiments of the present invention described above will now be described in detail with reference to the drawings. In this embodiment, the present invention is applied to a combustion apparatus of a water heater, and as shown in FIG. 1, the water heater has a heat exchange above a burner box (1) having a combustion chamber. It consists of a series of cans (K) with built-in vessels.

This can body (K) has a well-known structure, in which a heat exchange section having a structure in which a heat absorbing tube having a large number of fins is meandered is arranged in the vicinity of an open upper end of a cylindrical can body. An exhaust device (not shown) is connected to the upper end of the body. The burner box (1)
A gas burner (B) is built in the cylindrical chamber, and the gas supply pipe (N) arranged on the side of the gas burner (B) and the combustion air to the gas burner (B) are supplied. fan
Each has a built-in air supply device for forced air supply from (F).

The burner box (1) is constructed as a bottomed rectangular tube as a whole, and has a box main body (1a) in which a rear wall and both side walls are integrated.
And a front plate (1b) that closes the front opening, and a bottom plate (1c) that closes the lower end of the tubular body formed by them. As shown in FIG. 3, the box main body (1a) has a structure in which flange portions (10a) and (10b) provided with upright pieces (11) are projected on the peripheral edges of the upper and lower ends. Subject (1a) is
Once, as shown in FIG. 2, the flange corresponding portions (La) (L) (L) corresponding to the flange portions (10a) (10b) from both upper and lower sides of the metal rectangular plate.
a) is a dish-shaped body provided with an upright piece (11) and is manufactured by bending it into a U-shape. The upper flange portion (10a) is the flange-equivalent portion (La) thus bent. Front of flange (1
9) are connected in series to form a rectangular annular flange portion (10a).

When a rectangular plate provided with flange equivalent portions (La) and (Lb) is bent into a U-shape, it depends on the bending curvature, but in any case, at the bent portion, the flange equivalent portion becomes an obstacle. . Therefore, in the flange equivalent part (Lb) that becomes the lower flange part (10b), the range corresponding to the bent part is the cutout part (L ₁ ) and the flange equivalent part corresponding to the upper flange part (10a).
In (La), the tongue piece (L ₂ ) is left in the center of the range corresponding to the bent portion, and both sides thereof are cutout portions (L ₁ ). The tongue piece (L ₂ ) is set in a shape in which a strip-shaped member having a constant width includes an upright piece (11) like the cross section of the flange corresponding portion (La).

The flange equivalent portion (La) and the flange front portion (1
9) is connected by means such as spot welding, but in the continuous state, the upper surface of the flange equivalent portion (La) and the upper surface of the flange front portion (19) are flush with each other, as shown in FIG. As shown in the figure,
A step portion (19a) corresponding to the thickness of (La) is provided. The burner box (1) constructed in this way has a can body (K) above it.
, And a mounting flange (K ₁ ) is provided around the lower end of the can body (K), and the size is set so that the mounting flange (K ₁ ) is just fitted into the upright piece (11). Then, the can body (K) that has been assembled into a predetermined structure in advance has a heat resistant packing (G
₁ ) is connected between the flange portion (10a) and the flange (K ₁ ) by caulking, screwing or the like.

Since the upper surface of the flange portion (10a) is formed in a uniform plane, this allows the can body (K) and the burner box to be formed.
The confidentiality of the connection with (1) is secured. This secret may be a seal that blocks combustion exhaust, but heat resistance is required, so glass wool, asbestos, or the like is used as the heat-resistant packing (G ₁ ). These materials are very brittle.

Therefore, the lower surface of the heat-resistant packing (G ₁ ) does not come into contact with the flange portion (10a) at the portion corresponding to the cutout portion (L ₁ ) of the corner portion of the flange portion (10a). The heat-resistant packing (G ₁ ) tends to come off to the outside, which is likely.
However, in the above-described embodiment, the corner portion of the flange portion (10a) has the cutout portions (L ₁ ) (L ₁ ) set to be relatively small, and the cutout portions (L ₁ ) (L ₁ ) Since there is a tongue piece (L ₂ ) between them, and the upright piece (11) at the tip of this is in contact with the edge of the heat resistant packing (G ₁ ), the heat resistant packing (G ₁ )
The corner portion of is held, and it is possible to prevent the shift to the outside in the above situation. The range of the notch (L ₁ ) is the flange (10
Instead of being arranged over the entire width of a),
Since there is a small flange portion (L ₃ ) following the flange portion (10a) on the inner peripheral portion, the heat resistant packing (G ₁ ) is pinched by the flange portion (10a) and the flange (K ₁ ) over the entire area.

A gas burner (B) is stored in the burner box (1).
This gas burner (B) is shown in Figs.
The elongated flame hole (B₂), And a large number of flat top and bottom
Burner alone (B₁) Side by side in the burner box (1).
Each burner alone (B₁) Is a so-called light and dark burner
I am doing it. Therefore, the flame hole (B₂), The high gas concentration
No. 1 flame hole (H₁) And gas concentration
The second flame hole (H₂) And are parallel to the left and right
The structure of the flame hole (B₂The flame holes at the left and right ends of
Highly concentrated first flame hole (H₁) (H₁). In addition, this concentration
In the light burner, the burner body with high gas concentration and the gas concentration
Burner body configuration that overlaps the low burner body
As a result, each burner body's primary air outlet is
Le (N₁) (N ₁) Is corresponded. Gas from each nozzle
By setting the volume and the primary air suction ratio to the specified values,
A separate gas-air mixture is generated,
Flame hole part (B₂) Is the first flame hole (H
₁) And the second flame hole (H₂) And.

The gas burner (B) is composed of a large number of burner units (B ₁ ) (B ₁ ) constructed in this way, and these burner units are integrally assembled by a frame for burner assembly. The frame has a front plate (21) and a rear plate (22).
And a second dispersion plate (23) connecting the lower ends thereof and having a large number of through holes, the front plate (21) and the rear plate (22).
The side parts are connected to each other by the side plates (24) and (24) to form a rectangular frame as a whole, and in the assembled state, a burner block as shown in FIGS. 5 and 6 is formed.

As shown in FIG. 1, the front plate (21) is
Burner alone (B₁The opening (25) is shaped to match the primary air inlet.
The burner block is housed inside the burner box (1)
In this state, the gas supply housed in the burner box (1) is installed.
Multiple nozzle holes (N) in feed pipe (N) ₁) And the opening (25) are separate
To face. Install the gas burner on the bottom plate (1c) of the burner box (1).
Install the air supply fan (F) so that it is located below (B).
The first dispersion plate with a predetermined space above it.
(12) is arranged and fixed, and the burner is attached to the first dispersion plate (12).
The block is placed and fixed.

The second dispersion plate of the burner block
(23) is placed and fixed on the first dispersion plate (12) with a predetermined space. Therefore, as shown in FIGS. 1 and 7,
A skirt portion (13) hangs from the rear side and the left and right side edges of the first dispersion plate (12), and the skirt portion (13) is a burner box.
It contacts the inner side wall of the box body (1a) of (1). Therefore, the bottom plate
A predetermined space that opens to the front is formed between (1c) and the first dispersion plate (12), and the combustion air supplied from the air supply fan (F) has a part of the front opening ( 13a) is supplied to the front chamber (14) of the burner block as primary air, and the other part is supplied to the first dispersion plate (12) and the first dispersion plate (12) through a large number of through holes of the first dispersion plate (12). It is supplied to the space between the two dispersion plates (23),
It is supplied as secondary air to the accommodating portion of the gas burner (B) through the through holes of the second dispersion plate (23).

Further, as shown in FIGS. 1 and 7, the second dispersion plate
On the (23), hanging pieces (23a) are formed extending from the left and right sides and the rear side. On the other hand, a rising piece (12a) that bends upward is connected to the front end of the first dispersion plate (12). The left and right width of the rising piece (12a) is set to a predetermined length in relation to the left and right width of the box body (1a). A gap having a width that allows the left and right hanging pieces (23a) to be inserted is formed between the side walls of the main body (1a).

Further, a plate-shaped stopper (21a) is attached to the lower end of the front plate (21) over the entire left and right sides of the second dispersion plate (23) so as to move rearward from the lower end of the front plate (21). The hanging piece (23a) at the rear side of the second dispersion plate (23) connected in series
(a) The above-mentioned rising piece (12
It is designed to face a). When assembling the gas burner (B) in the burner box (1), with the front plate (1b) not attached, it was previously contacted with the inner peripheral surface of the box main body (1a) and placed on the bottom plate (1c). The first dispersion plate (1
A burner block is inserted on the upper surface of 2).

Therefore, the hanging piece (2) on the rear side of the second dispersion plate (23) is
3a) and the rear of the rising piece (12a) of the first dispersion plate (12).
Place the left and right hanging pieces (23a) (23a) through the gap.
Insert the burner block like
The stopper (21a) and the rising piece (12a) contact each other
In addition, the rear hanging piece (23a) is the inner surface of the rear wall of the box (1a).
It will be in contact with. As mentioned above, the burner block
Is a large number of burner units (B ₁), And a frame etc.
Since it is equipped with, the total weight is heavy and the handling is troublesome.
However, part of it is placed on the first dispersion plate (12) as described above and
Position in place just by pushing while riding
Therefore, the assembling work of this is easy.

The vacant chamber below the first dispersion plate (12) is formed by the skirt portion (13) and the inner peripheral surface of the box body (1a) being in contact with each other, so that the left and right side portions of the first dispersion plate (12). Also, air leakage from the rear side portion hardly occurs. Also, the vacant space between the first dispersion plate (12) and the second dispersion plate (23) is mainly composed of a hanging piece (23) and a box.
(1a) and the stopper (21a) and rising piece (1a)
Since it is securely surrounded by contact with 2a), air leakage from the periphery of the second dispersion plate (23) is unlikely to occur. Therefore, the degree of dispersion of the secondary air by the first dispersion plate (12) and the second dispersion plate (23) is made uniform, and the dispersion of the primary air distribution ratio to the front chamber (14) can be eliminated.

When the burner block is installed as described above, thereafter, parts such as the gas supply pipe (N) are installed in the front chamber (14), and the box main body (1a) is installed by the front plate (1b). Although the front opening of the gas burner is closed, this front plate (1b)
Upper plate (15) for closing the front side that coincides with the upper area of (B)
And a lower plate (16) for closing the front surface of the lower region thereof, and the upper plate (15) has a discharge mechanism portion of the ignition device,
The detection tool (S) of the flame detection device is attached.

The above-mentioned detector (S) is the second burner from the end.
Single unit (B₁) Flame hole (B₂) Above the detector (S₁)
The discharge mechanism is attached to the electrode.
It consists of a plate (T) and a spark plug (P), and is the fourth bar from the end.
Anna (B₁) Flame hole (B₂). The ignition
The plug (P) is an electrode part (P₁)
This electrode part (P₁5), the tip of FIG.
Like the flame hole (B₂) 1st flame hole (H ₁) Inside gas concentration
Second flame hole with low degree (H₂) So that it is located above
To be In addition, this electrode part (P₁), The electrode plate (T) facing
Similarly, it is attached to the upper plate (15) and its tip is
Single unit (B₁), That is, the first flame hole (H₁) Outside
Touch the edge. Also, install it at the tip of this electrode plate (T).
Cathode part (T₁) Is the flame hole (B₂) Slightly above the side edge
Is located in.

As a result, discharge sparks from the electrode portion (P ₁ ) to the cathode portion (T ₁ ) are generated from the jet area of the air-fuel mixture having a low gas concentration to the jet area of the air-fuel mixture having a high gas concentration. Since it passes through the proper ignition concentration range existing in the ignition discharge path, reliable ignition performance can be obtained. In this embodiment, as shown in FIG. 1, the spark plug (P) on the inner surface of the upper plate (15)
Directly above, cut and raise the part corresponding to this insertion hole when forming the insertion hole of the spark plug (P) in the upper plate (15),
A protective plate (17) is provided so as to be bent obliquely upward. Therefore, the dew passage water generated on the inner surface of the burner box (1) is
Even if it flows down from above (P), it will be guided to the left and right of the spark plug (P) by the protective plate (17), and the spark plug (P) and the upper plate (15) as a mounting part of it will be exposed. The inconvenience of a short circuit due to road water is also eliminated. Further, since the protective plate (17) for this purpose is formed at the same time when the insertion hole of the ignition plug (P) is formed, there is no waste of material, no assembly work is required, and the insertion hole of the ignition plug is not required. There is no displacement of the protective plate.

Incidentally, this structure is also adopted in the mounting portion of the other detecting tool (S). Further, in this embodiment, the spark plug (P) and the electrode plate (T) are the upper plate (1b) constituting the front plate (1b).
Although it is attached to 5), as shown in FIG. 9, it may be attached to the upper part of the main wall of the box (1a). Also in this case, as in the case described above, the protection plate (17) can be formed by cutting and raising.

[Brief description of drawings]

FIG. 1 is a sectional view of a water heater according to an embodiment of the present invention.

[Fig. 2] Explanatory drawing of an intermediate product before forming the box main body (1a)

FIG. 3 is a perspective view of the box main body (1a)

FIG. 4 is a cross-sectional view taken along the line YY of the main box body (1a).

FIG. 5 is a plan view of a burner block.

FIG. 6 is an explanatory view of a front main part of a burner block.

[Fig. 7] Exploded view of the bottom of the burner box (1)

FIG. 8 is a sectional view of the flame hole portion of the gas burner (B ₁ ).

FIG. 9 is an explanatory view of another mounting example of the spark plug (P) and the like.

[Explanation of symbols]

(H ₁ ) ・ ・ ・ First flame hole (H ₂ ) ・ ・ ・ Second flame hole (T) ・ ・ ・ Electrode plate (B ₂ ) ・ ・ ・ Flame hole part (P) ・ ・ ・ Spark plug (P ₁ ) ... Electrode part

Claims (1)

[Claims] 1. A first flame hole (H₁)When
Second flame hole (H₂) And alternating gas
A large number of flame holes were formed in the burner ignition device.
The structure of the flame hole is changed to the first flame hole (H₁) Is placed
The first flame hole (H₁) Along the outer edge
Attach the electrode plate (T) to the flame hole (B₂) Above the first flame hole
(H₁) Inside the second flame hole (H₂) Above the spark plug (P)
Pole (P ₁), And the electrode part (P₁) To the electrode plate (T)
Ignition device