JP2631183B2 - Gas combustion system using hot plate heating type gas burner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas burner used in a pottery for baking objects such as fish and meat, and in particular, a hot plate is heated to a red hot state by a gas burner of a forced combustion system. The present invention relates to a gas combustion device using a so-called hot plate heating type gas burner of a type in which the object to be fired is baked by radiant heat and heating by combustion exhaust gas.

[0002]

2. Description of the Related Art Japanese Patent Application No. Hei 4-20263 discloses a pottery apparatus for baking objects such as fish and meat placed on a grill.
No. 5 invention was proposed. In this kind of pottery apparatus, a plurality of burners (2) and (2) are arranged side by side in a casing (1) which is opened upward, and as shown in FIG.
(2) (2) is composed of a burner pipe (21) and a hot plate (22) opposed thereto at a predetermined interval above the burner pipe (21).

[0003] As shown in FIG.
A nozzle (24) for supplying gas to the upstream end of (1) is inserted, and a pilot burner (61) and a switch for igniting the pilot burner (61) are provided adjacent to the side of the burner (2). Parker
An ignition device (63) constituted by (62) is provided. The reason why the ignition device is arranged beside the burner (2) in this way is that
Because the gap between the burner pipe (21) and the hot plate (22) is small, it is difficult to dispose the ignition device (63) in the gap.

In this case, when an ignition operation is performed, first, an ignition device (63) is operated. That is, the sparker (62) operates to put the pilot burner (61) in a combustion state. Next, air supplied from the discharge port (300) of the forced air fan (30) is supplied from the primary air port (29) formed near the upstream end of the burner pipe (21) to the burner pipe (21). Then, the inflow air and the gas from the nozzle (24) are mixed in the burner pipe (21), and are ejected from the flame holes (25) and (25).

The air-gas mixture blown out from the flame holes (25) (25) of the burner pipe (21) fills the gap between the air-gas mixture and the hot plate (22) thereabove, and this is the hot plate (22). Overflowing from the side edge of
The spilled gas is ignited from the pilot burner (61), which burns the burner (2). However, there is a problem that the ignition operation to the burner (2) cannot be performed smoothly in the above-described conventional apparatus.

[0006] The above problem will be described in more detail.
The pilot burner (6
1) Since the ignition is performed from one side, if a crosswind is generated around the burner (2) during the ignition, the flame of the pilot burner (61) comes off the proper formation area, and
Smooth ignition of (2) cannot be realized.

The present invention has been made in view of the above points, and has been made in consideration of "a burner pipe (21) and a hot plate (22) located thereabove.
And an igniter comprising a pilot burner and the like disposed near the burner (2) .The hot plate (22) is red-heated by the burner pipe (21). The object is heated by the radiant heat ”.
An object of the present invention is to make it possible to smoothly perform an ignition operation of a burner (2).

[0008]

The technical means of the present invention for solving the above-mentioned problem is as follows.
, So that the flame generated by the pilot burner travels from the lower surface of the burner pipe (21) above the lower surface of the burner pipe (21) to the vicinity of the upper surface of the burner pipe (21). "

[0009]

The above technical means operates as follows. When the ignition operation is performed, a flame is formed in the pilot burner constituting the ignition device in the same manner as in the related art. Then, the flame of the pilot burner is located below the burner pipe (21), and the flame of the pilot burner is
The flame extends from the lower surface to the vicinity of the upper surface through the outer peripheries on both sides thereof, so that the flame penetrates deep into the gap between the burner pipe (21) and the hot plate (22) thereabove. That is, the flame enters from both sides of the burner pipe (21) to the vicinity of the flame hole.

[0010]

The present invention has the following specific effects. Since the flame of the pilot burner enters the vicinity of the flame hole from both sides of the burner pipe (21), even if a crosswind occurs at the time of ignition, one of the pilot burner flames formed on both sides of the burner pipe (21) must be formed. Since the burner (2) penetrates into the vicinity of the flame hole, the ignition operation of the burner (2) is ensured.

[0011]

Next, an embodiment of the present invention will be described in detail with reference to the drawings. In this embodiment, a gas burner having the above-described configuration is arranged in parallel with a rectangular grate, and the present invention is applied to a pottery apparatus of a type in which an object to be baked is baked in an upper area thereof. The details of the pottery apparatus will be described below.

As shown in FIGS. 1 and 2, this pottery has a rectangular grate (10) which is open on the top of a casing (1).
A plurality of gas burners (2) (2) composed of a burner pipe (21) and a hot plate (22) are arranged in parallel between the front and rear side walls in the grate (10), and the casing At the upper part of the front wall of (1), a front box (3) having an operation unit is provided, and a fan (30) is provided in the front box (3) and each of the gas burners is provided.
In (2), an air supply device for supplying primary air for combustion is accommodated, and an ignition device is provided. On the other hand, a flame detection device is provided on the rear wall of the fire bed (10).

Hereinafter, these units will be described. [About gas burner (2)] The gas burner (2) is shown in FIG.
As shown in FIG. 5, it is composed of a burner pipe (21) and a hot plate (22). The burner pipe (21) is made of a metal pipe that is open at the front and has a flattened rear end and is closed.A pair of primary air holes (29) and (29) are provided near the open end. It is formed on the side wall. The closed end (23) is screwed to a rear bar (11) provided along the wall in the rear wall of the grate (10), and the other front open end is housed in an air supply device described later. It is supported by being fitted over the nozzle (24). Burner pipe (2
1) Since the rear end is screwed by the rear crosspiece (11), even if the front open end only fits outside the nozzle (24), the burner pipe (21) is in the grate (10). The arrangement position in the front-back direction is fixed. And multiple burner pipes (2
1) (21) are similarly supported and arranged in parallel.

As shown in FIG. 4, a large number of flame holes (25) are arranged at predetermined intervals along the longitudinal direction on the top surface of each burner pipe (21), and near the closed end (23). Has multiple auxiliary flame holes
(26) and (26) are formed. The opening direction of the auxiliary flame holes (26) is set in the radial direction of the burner pipe (21) as shown in FIG. 7 in order to facilitate processing. The gas burner (2) of this embodiment is used for natural gas and LP gas, and these flame holes are divided into first flame holes (25a) (25a) group at the open end side and second flame holes (25b) at the center. (25b) group and the third flame hole (2
5c) and (25c) are classified into three types, and the diameter of the flame hole on the side of the closed end (23) is set smaller than that of the other.

In this embodiment, the amount of combustion by one burner pipe (21) is set to 1200 Kcal.
a) is 1.9 mm in diameter, 16 pieces, the second flame hole (25b) is 1.8 mm in diameter, 12 pieces, and the third flame hole (25c) is 1.7 m in diameter.
m, number: set to 23. Also, the third flame hole (25c)
The diameter of the auxiliary flame hole (26) near the closed end (23)
Two more 1.6mm flame holes are formed.

A hot plate (22) is laid back and forth above the burner pipe (21) at regular intervals. This hot plate
(22), as shown in FIG. 3, is a configuration in which a heat-resistant strip-shaped metal plate is bent so as to have a semicircular cross-section, and is supported in a posture in which an open portion of the cross-section faces downward. In order to maintain the space between the burner pipe (21) and the hot plate (22),
As shown in FIG. 2, the rear end of the hot plate (22)
, And is supported by a bracket (12) protruding into a grate (10), and the other front end is supported by a bracket (27) provided on a burner pipe (21).

As shown in FIG. 6, the bracket (12) is attached to the rear crosspiece (11) together with the closed end (23) by a mounting piece (1).
2b) and a rising piece (12
c), and a supporting portion (12a) projecting forward from the upper end thereof. The supporting portion (12a) is set so as to coincide with the inner periphery of the cross section of the hot plate (22), and the hot plate ( 22) The rear end is placed.

As shown in FIGS. 4 and 5, the other bracket (27) includes a backing plate (27a) having an upright plate larger than the projection surface at the front end of the hot plate (22), and a base end portion thereof. And a receiving plate (27b) projected in the longitudinal direction of the burner pipe (21) and spot-welded to the backing plate (27a), and extending from the lower end of the backing plate (27a) to the open end side of the burner pipe (21). Horizontal plate (2
7a ₁₎ pair of mounting tongues on both sides (27a ₂₎ is provided for, and is fixed by spot welding to the cross sides of the burner pipe (21). Thereby, the receiving plate (27b) is arranged in parallel along the top of the burner pipe (21). This backing plate
Upright pieces (27c) and (27c) are continuously provided on the left and right sides of (27b), and the interval between these upright pieces is adapted to the interval between both ends of the cross section of the hot plate (22), and the upright pieces (27c) ( The front end of the hot plate (22) is placed between the heat plates (27c), and the front end surface of the hot plate (22) faces the backing plate (27a) at a predetermined interval.

By providing a predetermined height difference between the height of the receiving plate (27b) and the height of the support portion (12a), both ends of the rear bar (11) and the bracket (27) are provided. The hot plate (22) supporting is parallel to the burner pipe (21). In the gas burner (2), the hot plate (22) is heated by the gas blown out from the flame hole of the burner pipe (21) to be in a red-hot state. Therefore, the burner pipe (21) and the hot plate (2
Although thermal expansion occurs during use in 2), only the closed end (23) of the rear end of the burner pipe (21) is screwed, and its front open end only fits externally to the nozzle (24). Therefore, even if the thermal expansion occurs, it can be absorbed. In addition,
Due to this thermal expansion, the position of the primary air holes (29) (29) also
(24), but in this embodiment, the distance between the tip (gas discharge port) of the nozzle (24) and the primary air hole (29) in a state where thermal expansion has not occurred is a normal value. It is set larger than that of Bunsen burner. Therefore, even in the state where the thermal expansion has occurred, the distance between the primary air holes (29) and (29) and the tip of the nozzle (24) is kept sufficiently large, and it cannot be determined that the burner pipe (21) thermally expands. Irrespective of this, the ejector effect due to the gas ejection from the nozzle (24) is made equal to prevent a variation in the primary air amount.

In the above embodiment, the hot plate (22) is detachably mounted with both ends of the hot plate (22) mounted on the brackets (12) and (27). ) And the bracket (12) may be fixed. That is, the rear end of the hot plate (22) is fixed to the bracket (12), and the other front end is slidably supported by the bracket (27) fixed to the burner pipe (21).
This stabilizes the hot plate (22). Further, since one end of the hot plate (22) is fixed and the other end is slidably supported by a bracket (27) fixed to the burner pipe (21), the heat expansion substantially corresponds to the thermal expansion of the hot plate (22). Synchronously, the burner pipe (21) thermally expands and its support position moves forward. Accordingly, the amount of relative movement of the front end of the hot plate (22) by the bracket (27) in the support portion is extremely small, and the problem due to thermal expansion is further reduced. [Air supply device] The air supply device includes the above-mentioned fan (30) and an air supply chamber (31) communicating with the discharge port of the fan (30). As shown in FIG. The nozzle (24) and the vicinity of the open end of the burner pipe (21) are accommodated therein. And
The pair of primary air holes (29) (29) of the burner pipe (21) is located in the air supply chamber (31).

The air supply device has a configuration in which one fan (30) and an air supply chamber (31) correspond to three gas burners (2) (2) arranged in parallel in the grate (10). The opening (32) formed below the juxtaposed portion of the three nozzles (24) and (24) on the bottom wall of the air supply chamber (31) formed in a rectangular parallelepiped box and the discharge of the fan (30). The outlet is communicated with the guide duct (33). Therefore, primary air for combustion is forcibly sent from the discharge port of the fan (30) into the air supply chamber (31), and this is the three burner pipes (21) (21).
Is forcibly supplied through the primary air holes (29) (29).

The gas burner (2) is of an all-primary air type, and air required for combustion is supplied by the supply air. A temperature fuse (34) is mounted on the upper surface of the air supply chamber (31) to enhance the safety of each gas burner (2) during backfire. The temperature fuse (34) is turned off when the inside of the air supply chamber (31) reaches an abnormal heating temperature, and is inserted and connected into the electric circuit for driving the solenoid valve that controls the opening and closing of the switch. The device is closed, combustion is stopped, and safety is ensured. [Ignition device] An ignition device is provided for each gas burner (2), and as shown in FIG.
It is arranged below (21).

The ignition device includes a pilot burner (41) obtained by bending a relatively thin metal pipe into an L-shape, and a cathode portion attached to a horizontal tube extending horizontally at the upper end of the pilot burner (41). (42), and a guide cylinder disposed to face a pilot flame hole (41a) opened at an end of the horizontal tube and guiding the flame of the pilot burner (41) upward. (44). The guide cylinder (44) is a box body having a rectangular cross section, and has a wall (45) whose tip wall faces obliquely upward and upward.

In this apparatus, when gas is discharged from a pilot nozzle (46) provided at the lower end of the pilot burner (41) by the output of the ignition control device, at this time, the electrode (43) and the cathode (42) ), Whereby the pilot burner (41) is ignited, and the flame of the pilot burner is guided upward, and through the opening (45) through the outer periphery of the burner pipe (21) as shown in FIG. It is guided to the space between the pipe (21) and the hot plate (22). A predetermined time before the ignition operation, the fan (30) is turned on and the gas circuit to the nozzle (24) is opened at the same time as the ignition operation, so that a gas is formed at the top of the burner pipe (21). Flame hole (25) (2
The air-gas mixture discharged from 5) is ignited by fire and the gas burner (2) becomes in a combustion state. As described above, in the above-described apparatus, the ignition operation is performed in a state where the flame of the pilot burner (41) travels along the outer circumference on both sides of the burner pipe (21) and penetrates deep into the gap between the burner pipe (21) and the hot plate (22). Therefore, even if a crosswind occurs at the time of ignition, one of the pilot burner flames formed on both sides of the burner pipe (21) always enters the vicinity of the flame hole, so the ignition operation of the gas burner (2) is ensured .

In particular, in the case of the gas burner of the hot plate heating type of the all-primary air combustion as in this embodiment, since the amount of air in the air-fuel mixture is larger than that of the Bunsen combustion, the burner pipe (21) and the hot plate ( Outside the gap with 22), the concentration of the fuel gas becomes too low to ignite, and it is necessary to ignite inside the gap. Therefore, the present invention works particularly effectively. In addition, the flame of the pilot burner heats the burner pipe (21) from directly below, and the temperature of the mixture rises, increasing the combustion speed and facilitating ignition during cold start (when the burner pipe (21) is cold). To

Thereafter, the gas circuit to the pilot burner (41) is cut off and the pilot burner (41) extinguishes,
Only the gas burner (2) is in a combustion state. In the above embodiment, the pilot burner (41) is arranged below the burner pipe (21) in the front box (3), and the flame formed by the pilot burner (41) is guided by the guide cylinder (44). The guide tube (44) is not provided, but the flame of the pilot burner (41) is transmitted directly to the outer circumference on both sides of the burner pipe (21) without guiding the pipe (44). If the flame of the pilot burner (41) is formed below the burner pipe (21), the pilot burner (41) does not need to be located below the burner pipe (21). Is also good.

Although this embodiment shows an example in which a burner of the all-primary type is used, the so-called Bunnsen ignition for igniting with the excess air ratio being less than 1 is performed, and then the heat for continuously Bunsen combustion is performed. The present invention can be applied to a plate-heating gas burner. [Flame detector] Each gas burner (2) is provided with a flame detector near the closed end (23).

This device, as shown in FIGS. 2 and 6,
A thermocouple (51) heated by the flame from the auxiliary flame holes (26) (26) provided near the closed end (23), and a thermoelectric force generated by the thermocouple (51) within a predetermined time after the start of the ignition operation. A flame detection circuit (C ₁ ) that outputs a predetermined output signal when the level reaches the level, and a gas switching device inserted into the gas circuit when a predetermined output from the flame detection circuit (C ₁ ) is input. And an output device (C ₂ ) for maintaining the valve open. Therefore, when a predetermined output signal is input from the flame detection circuit (C ₁ ) to the output device (C ₂ ) within the set time after the start of the ignition operation, the gas switching device is maintained in the valve open state and the gas burner ( If the combustion of 2) continues, and conversely, even when the set time has elapsed, if the thermoelectromotive force from the thermocouple (51) does not reach the predetermined output level, the gas switching device is not maintained in the open state. That is, the gas switching device is closed, and safety in the event of ignition failure is ensured.

The thermocouple (51) generates a thermoelectromotive force when its tip is heated to a predetermined temperature. In this embodiment, the thermocouple (51) includes a bracket (12) and a stopper plate (13). It is mounted so as to penetrate the rising pieces (12c) (13c), and is held in a horizontal position by a holding plate (53) screwed to the rear crosspiece (11), and its tip end is an auxiliary flame hole (26). The holding position is determined so as to be located near and above (26).

Accordingly, when the gas burner (2) is in a combustion state, the hot plate (22) is heated by the combustion flame from the auxiliary flame holes (26), particularly the stable combustion flame by the flame holding action. The radiant heat stably heats the tip of the thermocouple (51). [About Combustion of Gas Burner (2)] As described above, in the gas burner (2) of this embodiment, the primary air is forcibly supplied by the fan (30) and burns. Since the excess ratio is set to 1 to 1.2, the air-gas mixture discharged from each of the flame holes burns in a state where the air-gas mixture collides with the inner surface of the hot plate (22) having a semicircular cross section. The flame separates from the flame hole of the burner pipe (21) and forms a so-called thin film combustion formed along the inner surface of the hot plate (22) as shown in FIG. 3, and the temperature of the combustion flame becomes extremely high. Also hot plate
Since (22) has a semicircular cross section, this combustion flame
There is no overflow outside (22). Therefore, the hot plate (22) is efficiently heated, and the entire cross section of the hot plate (22) is uniformly heated.

The same applies to the flame formed by the auxiliary flame holes (26). In addition, natural gas and LP
In the case of a gas burner (2) for use, in order to ensure stable combustion, the total area of the burner hole of the burner pipe (21) is reduced by other low wobbe gas species due to the relationship between the combustion speed and the injection speed of air-fuel mixture from the burner hole. (Excluding A gas), it is much larger. Accordingly, when the air-gas mixture is forcibly supplied into the burner pipe (21) at the above-mentioned excess air ratio, FIG.
When the pressure distribution in the burner pipe (21) due to this supply pressure becomes high from the upstream side to the downstream side, and when the flame hole diameter is made constant, the distribution of the amount of gas ejected from each flame hole becomes This follows the pressure distribution.

However, in this embodiment, as described above, the group of flame holes of the burner pipe (21) is changed to the first flame holes (2
5a) (25a) group, 2nd flame hole (25b) (25b) group in the middle area, and 3rd flame hole (25c) (25c) group on the downstream side are divided into three groups, from upstream to downstream The diameter of the flame hole is gradually reduced toward.
Accordingly, the distribution of the jet gas amount when the flame hole diameter is fixed is corrected, and the amount of gas ejected from each part of the burn hole group of the burner pipe (21) can be made uniform. In the case of the low wobbe gas species, since the total area of the flame holes is small, the structure may be such that the flame holes having a constant diameter are arranged at a predetermined pitch.

In this gas burner (2), the thermocouple (51) faces the endmost flame hole of the flame hole group arranged in a line.
The flame formed in the flame hole is cooled by the outside air and tends to become unstable, and the combustion flame in the portion is not stabilized. Therefore,
The thermocouple (51) is not stably heated and its output becomes unstable, so that misfire detection is likely to be erroneous. Therefore, in the present embodiment, a plurality of auxiliary flame holes (26) and (26) are provided to perform so-called "flame holding" for stabilizing the flame in the portion, so that a stable output can be obtained from the thermocouple. Also, as described above, since it is of the all-primary air type which is forcibly supplied by the fan (30) and the gas ejected from the flame hole which has collided and diffused on the lower surface of the hot plate (22) burns, FIG. A thermocouple (51) directly or by a thin high-temperature combustion flame formed on the lower surface of the hot plate (22) above the auxiliary flame holes (26) and (26) or by radiant heat from the combustion film. Is heated. Therefore, this auxiliary flame hole (2
6) By setting the diameter of (26) smaller than the main flame such as the third flame (25c), the temperature of the combustion flame by the auxiliary flame (26) (26) for heating the thermocouple (51) is By making the temperature lower than that of the main flame hole, the inconvenience of the thermocouple (51) being abnormally overheated is prevented.

[Brief description of the drawings]

FIG. 1 is an overall view of a combustor.

FIG. 2 is a vertical cross-sectional view of an arrangement portion of a gas burner (2).

FIG. 3 is a longitudinal sectional view of a gas burner (2).

FIG. 4 is a plan view of a burner pipe (21).

FIG. 5 is a side view of the burner pipe (21).

FIG. 6 is an enlarged sectional view of a fixing portion of the burner pipe (21) and the thermocouple (51).

FIG. 7 is a longitudinal sectional view of the gas burner (2) near the auxiliary flame hole (26).

FIG. 8 is an explanatory view showing a relationship between a guide cylinder (44) and a gas burner (22).

FIG. 9 is an explanatory diagram of an internal pressure along a burner pipe (21).

FIG. 10 is an explanatory view of a conventional example.

FIG. 11 is an explanatory view of a conventional example.

[Explanation of symbols]

 (2) ・ ・ ・ Burner (21) ・ ・ ・ Burner pipe (22) ・ ・ ・ Hot plate

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masao Aramatsu 2-26, Fukuzumi-cho, Nakagawa-ku, Nagoya Linhai Co., Ltd. (56) References Shiro 59-54 (JP, U) Shiro 60 -50321 (JP, U)

Claims (1)

(57) [Claims] 1. An ignition device comprising a burner (2) composed of a burner pipe (21) and a hot plate (22) located above the burner pipe, and a pilot burner disposed near the burner (2). In the configuration in which the heating plate (22) is red-heated by the burner pipe (21) and the object is heated by the radiant heat, the flame of the pilot burner is provided below the burner pipe (21). A gas combustion apparatus using a hot plate heating type gas burner in which a flame generated by the pilot burner is positioned so as to travel from the lower surface of the burner pipe (21) above the outer periphery of both sides to reach near the upper surface thereof.