JP2551852Y2 - Low pressure drop type gas burner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a Bunsen-type low-pressure-drop type gas burner used for a natural-ventilated gas-fired device, and in particular, to equalize the flame and prevent the lifting of the flame. And a gas burner that is effective.

[Prior Art] A conventional gas burner of this type will be described with reference to FIGS. 6 and 7. FIG.

In the figure, reference numeral 1 denotes a burner main body (unit burner). The burner main body 1 is formed by a sheet metal press working, and a mixing pipe 3 continuously provided from a bell mouth 2, a burner head 4 provided above the mixing pipe 3, and a burner head 4. A plurality of slit-shaped flame holes (main flame holes in the case of the gas burner of the present invention) 6 are arranged in two rows on the upper surface 5 of the burner head 4. In addition,
A plurality of the above-described burner bodies 1 are integrated to form a low-pressure-loss gas burner.

Thus, the mixture supplied from the bell mouth 2 into the burner main body 1 flows to the burner head 4 via the mixing tube 3,
The gas is blown out of the burner main body 1 from the slit-shaped flame hole 6 of the burner head 4 and burns.

In such a gas burner, it is important to make the distribution of the flame in the burner head 5 uniform and to prevent the lifting of the flame by improving the thermal efficiency.

[Problems to be Solved by the Invention] However, in the above-described conventional gas burner, the flow rate of the mixture gas flowing from the mixing pipe 3 toward the flame hole 6 of the burner head 4 is reduced, and the distribution of the mixture gas ejected from the plurality of flame holes 6 is reduced. Since the uniformization is not considered at all, the distribution of the flame 7 is non-uniform, as shown by the two-dot chain line in FIG. Further, since the deceleration of the air-fuel mixture flow is not taken into account as described above, the flow velocity of the air-fuel mixture passing through the flame hole 6 is too large. It will be easier. For this reason, there are problems that the type of gas used is restricted, that TDR (so-called turndown ratio) cannot be made wide, and that combustion noise is large.

Accordingly, the present applicant has previously filed an application for a gas burner in which a wire mesh with a fine mesh is covered on a slit-shaped flame hole as a measure for preventing flame lifting. Although this gas burner is effective in preventing the lifting of flames, it is expensive due to the material cost of the wire mesh and the installation cost of the wire mesh, and also has a problem in durability because the wire mesh is glowing red. When it is attached, there is a problem that distortion occurs due to aging.

Further, as a measure to prevent the lifting of the flame, a gas burner in which a straightening plate provided with a large number of holes in a burner main body is fixed so as to partition between the flame hole and an air-fuel mixture flow path below the straightening plate has been proposed. However, in this gas burner, since the flow rate of the air-fuel mixture is extremely blocked by the above-mentioned flow straightening plate, there is a problem that when low calorie gas or the like is used, the flame returns to the position of the flow straightening plate at the time of ignition.

SUMMARY OF THE INVENTION An object of the present invention is to provide a gas burner which is effective in making the flame uniform and preventing the lifting of the flame.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention relates to connecting a bell mouth to a premixed gas jetting direction from a main flame hole at about 90 °.
A low-pressure-drop type mixing pipe that is not bent in the middle by introducing a premixed gas from the lateral direction, a burner head provided at the top of the mixing pipe, and a plurality of slit-shaped main flame holes provided in the burner. In a gas burner constituted by a burner main body having, a through hole for an auxiliary flame hole is formed on both upper sides of the burner head, and between the mixing pipe and the main flame hole in the burner main body. A throttle portion for decelerating the mixture flow and making the mixture distribution uniform is provided such that the projection of the throttle portion is located immediately below the through hole for the auxiliary flame hole, and on both upper sides of the burner head. An auxiliary flame hole forming plate that covers the through hole for the auxiliary flame hole is fixed, and communicates with the through hole for the auxiliary flame hole between an upper edge of the auxiliary flame hole forming plate and both upper and lower edges of the burner head. An auxiliary flame hole whose opening end is at the same level as the main flame hole surface is located close to the main flame hole. It is characterized by being formed by.

[Operation] Since the present invention is configured as described above, it is possible to decelerate the air-fuel mixture supplied by the throttle provided between the mixing pipe and the main flame hole and to make the air-fuel mixture uniform. Of course, in the present invention, the narrowed portion is provided so that the convex portion of the narrowed portion is located immediately below the through hole for the auxiliary flame hole.
The air-fuel mixture that has passed through the throttle generates a vortex inside the through-hole, and the negative pressure of the vortex stabilizes the introduction of the air-fuel mixture into the through-hole, thereby stably forming an auxiliary flame in the auxiliary flame hole. be able to. In addition, since the opening end of the auxiliary flame hole is formed near the main flame hole at the same level as the main flame hole surface, it is possible to directly contact the main flame and the auxiliary flame at the base of the main flame hole surface. This, combined with the stable introduction of the air-fuel mixture by the vortex inside the through hole for the auxiliary flame hole, stably prevents the lift of the main flame even if the combustion amount is reduced and the auxiliary flame becomes small. be able to.

[Embodiment] An embodiment of a gas burner according to the present invention will be described below with reference to FIGS. 1 to 5.

The same reference numerals in FIGS. 6 and 7 denote the same parts.

In the figure, reference numeral 8 denotes a portion between the mixing pipe 3 and the main flame hole 6 in the burner main body 1, that is, a portion where the mixing pipe 3 and the main flame hole 6 are wrapped, from both left and right outer sides to the inside of the burner main body 1. The throttle portion 8 is formed to have a substantially semi-circular cross section. The throttle portion 8 serves to reduce the flow of the air-fuel mixture and to make the distribution of the air-fuel mixture uniform.

Reference numeral 9 denotes a plurality of through holes for auxiliary flame holes provided on the left and right sides of the upper portion of the burner head 4, and a convex portion formed by a semicircular recess of the throttle portion 8 is located immediately below the through hole 9. To do.

Reference numeral 10 denotes an auxiliary flame hole forming plate. The auxiliary flame hole forming plate 10 is bent into a U-shape in cross section so as to cover the burner head 4 from above, and is formed by opening a portion of the upper plate except for front and rear ends 11. . On the upper part of the left and right side plates of this auxiliary flame hole forming plate 10,
A plurality of convex portions 12 which protrude slightly outward in a substantially rectangular shape are provided at equal intervals in correspondence with the through holes 9 for the auxiliary flame holes. The auxiliary flame hole forming plate 10 is placed on the burner head 4 and an appropriate flame between the auxiliary flame hole forming plate 10 and the burner head 4, for example, as indicated by a cross mark in FIGS. 4 and 5. The auxiliary flame hole forming plate 10 and the burner head 4 are fixed by performing spot welding or the like on the front and rear ends 11 of the upper surface plate of the hole forming plate 10 and flat portions between the convex portions 12 of the left and right side plates. As a result,
An auxiliary flame hole 13 communicating with the through hole 9 for the auxiliary flame hole is provided between the left and right corners of the upper portion of the burner head 4 and the upper end of the convex portion 12 of the auxiliary flame hole forming plate 10. It is formed close to the main flame hole 6 at the same level as the hole surface.

Since the gas burner of the present invention in this embodiment has the above-described configuration, the gas mixture supplied from the bell mouth 2 into the burner main body 1 passes through the mixing pipe 3 and the burner head 4.
When flowing to the (main flame hole 6), the mixing pipe 3 in the burner main body 1
When the air-fuel mixture collides with the throttle portion 8 provided between the main flame hole 6 and the air-fuel mixture, the flow velocity of the air-fuel mixture is moderately reduced, so that the air-fuel mixture flow can be decelerated. At the same time, the above-described throttle unit 8 can make the distribution of the amount of air-fuel mixture ejected from the plurality of slit-shaped main flame holes 6 uniform. Therefore, as shown in FIG. 2, the flame (main flame) 70 can be made uniform.

In addition, since the auxiliary flame hole 13 is provided near the main flame hole 6,
The auxiliary flame (so-called sleeve fire) 71 from the auxiliary flame hole 13 is located at the base of the main flame 70 from the main flame hole 6, so that the lifting of the uniform main flame 70 in the main flame hole 6 is prevented. Can be. In addition, since the convex portion of the throttle portion is located immediately below the through hole for the auxiliary flame hole, a vortex is generated inside the through hole for the auxiliary flame hole, and mixing into the auxiliary flame hole passing through the through hole occurs. The air supply can be stabilized, and the effect of preventing the above-described lifting of the flame can be further improved. Therefore, the type of gas used is not limited, and TDR (so-called turndown ratio)
Can be widened, and combustion noise can be prevented.

Further, since the auxiliary flame hole forming plate 10 is fixed to the burner head 4 by spot welding or the like, material costs and mounting costs are reduced as compared with a gas burner in which a mesh wire is covered with fine mesh on slit-shaped flame holes. Cost is low. Further, since the auxiliary flame hole forming plate 10 does not directly hit the flame, the durability is improved and there is no fear of distortion.

Furthermore, since the flow rate of the air-fuel mixture is moderately reduced by the throttle section 8 provided between the mixing pipe 3 and the main flame hole 6 in the burner main body 1, a flow straightening plate provided with a large number of holes in the burner main body is used. When a low-calorie gas or the like is used, such as a gas burner fixed so as to partition between the flame hole and the air-fuel mixture flow path under the flame hole, there is no danger that the flame will back up to the position of the rectifying plate at the time of ignition.

[Effects of the Invention] As described above, according to the present invention, the air-fuel mixture is supplied to the auxiliary flame holes. And stabilize this,
The fact that the auxiliary flame hole is formed close to the main flame hole at the same level as the main flame hole surface makes it possible to reliably prevent the lifting of the flame in the main flame hole.

[Brief description of the drawings]

1 to 5 show an embodiment of the gas burner according to the present invention. FIG. 1 is a plan view, FIG. 2 is a side view, FIG. 3 is a sectional view taken along line III-III in FIG. FIG. 4 is a partial perspective view,
FIG. 5 is a perspective view of an auxiliary flame hole forming plate. FIG. 6 is a plan view showing a conventional gas burner, and FIG. 7 is a side view of the same. 1 ... burner body, 2 ... bell mouth, 3 ... mixing tube,
4 ... burner head, 6 ... main flame hole, 8 ... throttle part, 9
…… Aperture for auxiliary flame hole, 10 …… Auxiliary flame hole forming plate, 13 ……
Auxiliary flame hole, 70 …… Main flame, 71 …… Auxiliary flame.

Claims (1)

(57) [Scope of request for utility model registration] 1. A low-pressure-drop mixing pipe which is connected to a bell mouth, introduces a premixed gas from a lateral direction of about 90 ° with respect to a premixed gas jetting direction from a main flame hole, and does not bend on the way; In a gas burner constituted by a burner main body having a burner head provided on an upper part of the mixing pipe and a plurality of slit-shaped main flame holes provided on the burner, a transparent flame for an auxiliary flame hole is provided on both upper sides of the burner head. A hole is formed, and a throttle portion for reducing the flow rate of the mixture and uniforming the mixture distribution is provided between the mixing pipe and the main flame hole in the burner main body for the auxiliary flame hole. An auxiliary flame hole forming plate fixed to both sides of an upper portion of the burner head, the auxiliary flame hole forming plate covering the through hole for the auxiliary flame hole; Between the upper edge of the burner head and the upper side edges of the burner head. A low pressure drop type gas burner, wherein an auxiliary flame hole whose opening end is in the same level as the main flame hole surface is formed in close proximity to the main flame hole.