JPH0552521U - Surface burning burner - Google Patents

Abstract

(57) [Summary] [Structure] A porous member 11 forming a combustion surface on the front surface,
A casing 2 extending from the vicinity of the outer periphery of the porous member 11 toward the rear surface, a mixed gas chamber 40 formed by the porous member 11 and the casing 2, and a combustion gas mixture supplied to the mixed gas chamber 40. In the surface combustion burner 1 having an opening 32 for holding, the porous member 11 is attached to the casing 2 by an appropriate fixing means such as a screw 50 while exposing substantially the entire area of the front surface thereof, and the surface of the screw 50 is Coat with heat resistant adhesive. [Effect] The casing can be prevented from being deformed by heat, and the easily-damaged members such as the porous material and the packing can be replaced, so that the burner itself has a long life. Further prevention of reduction of the radiation efficiency, reduction of No _x generation is provided.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a surface-combustion burner, and more particularly to a surface-combustion burner that prevents reduction in radiation efficiency of the burner to improve thermal efficiency and prevents deformation due to heat, thereby improving the life of the burner itself.

[0002]

[Prior art]

 Conventionally, a planar porous member made of, for example, ceramic, having pores communicating enough on the front and back sides to allow the combustion gas mixture to diffuse is provided, and the combustion gas mixture is supplied to the back surface thereof to diffuse the combustion gas mixture. Meanwhile, a surface combustion burner is known, which reaches the front surface of the planar porous member and is ignited and burned in the vicinity of the front surface. This type of surface combustion burner heats and heats a flat porous member to incandescent, and most of the energy is released as radiant heat, and the thermal conductivity of a porous member such as ceramic is usually small. Since the backside temperature does not rise so much even if the combustion temperature of the burner is considerably raised, it is possible to prevent the occurrence of flashback, and it is used in a wide range of fields as a burner with high thermal efficiency, not limited to household burners. ..

A typical configuration of the surface combustion burner will be described with reference to FIG. 2. In the surface combustion burner 10 shown in FIG. 2, the square or circular planar porous member 11 is provided with a heat resistant packing 12 interposed therebetween. Mounted on the front side of the tubular casing 13. The front end of the casing 13 is bent inward toward the inside in an L-shaped cross-section to form a flange 14, and the flange 14 covers the vicinity of the peripheral edge of the porous member 11 with a constant width to engage the porous member 11. It is stopped and positioned in the forward direction.

Inside the casing 13, combustion gas distribution means 20 for diffusing the combustion gas mixture and distributing it uniformly on the back surface of the planar porous member 11 is located. The combustion gas distribution means 20 is made of the same material as the casing 13, and includes a baffle plate 21 positioned in parallel with the planar porous member 11 and an annular member 22 fixed to the outer peripheral portion of the baffle plate 21 by an appropriate means. It consists of The annular member 22 has a U-shaped cross-sectional shape as shown in FIG. 2, and forms a circulation path 26 therein, and the baffle plate 21 is sandwiched between the inner peripheral wall portion 23 thereof. A plurality of openings 24 and 25 are formed in the front and the rear, respectively. The shape of the outer peripheral portion of the annular member 22 is the same as the shape of the inner peripheral wall portion of the casing 13, and is press-fitted into the casing 13 from the rear side so that the back surface of the planar porous member 11 is the front surface thereof and the flange of the casing. It is supported while being pressed against 14.

The combustion gas distribution unit 20 is supported by a back plate 30 having the same shape as the inner peripheral wall portion of the casing 13. The outer peripheral edge portion of the back plate 30 constitutes a bent portion 31, and the front end of the bent portion 31 and the rear end portion of the casing 13 are welded 35 over the entire circumference thereof. Further, a cylindrical tube 32 is fixed to the central portion of the back plate 30 by an appropriate means, and the cylindrical tube 32 is connected to a combustion gas supply source through an appropriate piping means (not shown).

Therefore, the casing 13, the flat porous member 11 and the back plate 30 form a mixed gas chamber 40 which is a closed space, and the mixed gas chamber 40 constitutes the combustion gas distributing means 20. The circulation path 26 defined by the member 22 and the casing 13, the front mixed gas chamber 41 defined by the planar porous member 11 and the baffle plate 21, the baffle plate 21 and the back plate 30 are defined. It is divided into a rear mixed gas chamber 42.

The combustion of this surface combustion burner is performed as follows. A combustion gas mixture from an appropriate gas source is press-fitted into the rear mixed gas chamber 42 from the cylindrical member 32. The injected combustion gas mixture collides with the baffle plate 21 and changes its flow direction, enters the circulation path 26 from the opening 25 provided in the inner peripheral wall portion 23 of the annular member 22, changes its direction again, and then the opening 24 Flows into the front mixed gas chamber 41. Meanwhile, the combustion gas and the air are well mixed and homogenized. The homogenized combustion gas mixture passes from the back surface of the planar porous member 11 through its continuous porosity and reaches the front surface, and the porous member 11 excluding the portion covered with the flange 14 of the casing 13 described above. It is ignited in front of and burns. Due to the combustion, the front surface of the planar porous member 11 becomes incandescent, and radiant heat is emitted.

[0008]

[Problems to be solved by the device]

 The surface combustion burner as described above is extremely effective in terms of effective utilization of heat and safety. However, since the heat of combustion generated during combustion is extremely high, it cannot always be said that the equipment has a sufficient life. In particular, when the casing 13 is used for a certain period of time, the L-shaped flange 14 portion of the casing 13 is deformed, and unevenness occurs in the mounting state of the porous member 11 with respect to the casing, which causes inconvenience in burner combustion.

For example, a so-called gas leakage state in which the combustion gas mixture does not pass through the porous member itself but is directly jetted and burned from the peripheral portion of the porous member in which such unevenness has occurred. Tends to occur. Therefore, in addition to reducing the combustion gas on the surface of the porous member and lowering the radiation efficiency, the flame generated by such gas leakage tends to become a combustion flame at a place where the air ratio is usually close to 1, Since a large amount of No _{x was} generated, improvement was required.

Further, since the porous member 11 is partially covered with the L-shaped flange 14 as described above, that portion does not directly act as a combustion surface, and as a result, the radiation efficiency is increased. Is causing a reduction in The porous material 11 is usually a sintered body of long fibers made of an alloy of iron, chromium, silicon, aluminum, yttrium, etc., and has a heat resistance of 1200 ° C. or higher. The same packing with high heat resistance, such as ceramic fiber sheet, is used as the packing, but in general, this type of combustor frequently repeats combustion and non-combustion, resulting in the entire device Since heating and cooling are frequently repeated, fatigue may occur earlier due to the porous material and heat resistant packing before the deformation of the casing 13, and the life of the burner itself may be affected.

Further, in the burner of the type shown in FIG. 2, the porous material and the heat resistant packing are enclosed at the front end position of the casing 13 in which the L-shaped flange 14 is integrally formed, In addition, since the front end of the bent portion 31 of the outer peripheral edge of the back plate 30 and the rear end of the casing 13 are weld-stopped 35 over the entire circumference, the burner can be disassembled to replace the internal member. It is practically impossible, and even if the combustion gas distribution means 20 inserted in the casing 13 or the inside thereof is fully usable, the burner is damaged when the porous material or the heat-resistant packing is damaged. It has the inconvenience of having to replace the whole.

The present invention is intended to eliminate the disadvantages of the conventional surface combustion burner as described above, and more specifically, to prevent the deformation of the burner and thereby prolong the life of the burner. , To obtain a burner with improved radiation efficiency. Another object of the present invention is to provide a burner with reduced No _x generation. Still another object of the present invention is to provide a burner having a long service life by allowing the burner itself to be disassembled and assembled so that the internal members can be replaced to facilitate the maintenance of the burner.

[0013]

[Means for Solving the Problems]

 In order to solve the above problems and to achieve the object, the present invention provides a porous member forming a combustion surface on the front surface, a casing extending rearward from the rear surface near the outer periphery of the porous member, and the porous member. In a surface combustion burner having a mixed gas chamber formed by a porous member and a casing, and an opening for supplying a combustion gas mixture to the mixed gas chamber, the multi-porous member exposes substantially the entire area of its front surface. In this state, the casing is attached to the casing or a member arranged in the casing by an appropriate fixing means, and the surface of the fixing means is coated with a heat resistant adhesive. Discloses a surface combustion burner.

[0014] It is a more preferable mode to use a fixing means by screwing as the fixing means because the burner can be disassembled and assembled. The material of the screw used for screw connection is preferably a heat-resistant material such as stainless steel, and as the heat-resistant adhesive, a ceramic adhesive is particularly preferable from the viewpoint of heat resistance.

Further, as the material constituting the casing, the porous member, etc. constituting the burner according to the present invention, the material used for the burner having the conventional structure can be used as it is.

[0016]

【Example】

 Hereinafter, the present invention will be described in more detail based on the description of one embodiment. FIG. 1 shows a sectional view of an embodiment of a surface combustion burner 1 according to the present invention. This embodiment has substantially the same shape as the surface combustion burner 10 described above based on FIG. 2 except for the shapes of the porous member, the casing and the back plate. The same reference numerals are given to the members, and detailed description thereof will be omitted.

In the surface combustion burner 1, the casing 2 is in the shape of a bottomed cylinder whose front portion is open, and a cylindrical tube 32 is fixed to an appropriate portion of the bottom portion 3 by an appropriate means. Similar to the conventional burner, the cylindrical pipe 32 is connected to the combustion gas supply source through an appropriate piping means (not shown). The material and thickness of the porous member 11 are the same as those used in the conventional burner, but in the present invention, the outer shape and size thereof are almost the same as the outer shape and size of the open front end of the casing 2. Has become. The outer peripheral edge portion is provided with a plurality of apertures 4 and 4 each having a taper that expands toward the front at appropriate intervals.

The heat-resistant packing 12 is also almost the same as the conventional one, but similar openings 14 and 14 are provided at positions facing the openings 4 provided in the porous member at the time of mounting. .. Inside the casing 2, the combustion gas distribution means 20 is located as in the conventional burner. In the illustrated case, when the combustion gas distribution means 20 is installed in the casing 2, the front surface portion 27 of the ring member 22 and the front end portion of the casing 2 are arranged at the same height. .. A screw hole 28 is formed in the front surface portion 27 of the ring member 22 at a position facing the opening 4 formed in the porous member 11.

The assembling of each member is performed as follows. First, the packing 12 and the porous member 11 are arranged on the front surface portion 27 of the ring member 22 of the combustion gas distribution means 20 so that the screw holes 28 and the openings 14 and 4 are aligned with each other. A heat resistant adhesive is applied to the openings, and screws 50, 50 are screwed in to fix each member together. After that, a heat-resistant adhesive is filled in the void portion of the screw hole to seal the opening of the screw hole.

After that, a heat-resistant adhesive such as a ceramic adhesive is applied to the bottom surface portion and the outer peripheral edge portion of the ring member 22 of the combustion gas distribution means 20 and is pushed into the casing 2, thereby Are united. The surface combustion burner 1 performs the same combustion action as the burner shown in FIG. However, in the surface combustion burner according to the present invention, the casing 2 does not have an inwardly bent flange portion for covering and locking the front surface of the porous member unlike the conventional one, The entire casing is located on the rear side of the porous member, which is a heating portion, via a heat resistant packing. Therefore, the heat conduction from the porous member, which is the heat source, to the casing is greatly reduced compared to the conventional one, and it is possible to prevent heat damage and thermal deformation of the casing and keep the burner in a normal state for a long time. It can be used.

Further, since the casing is not thermally deformed, the joint surface between the casing and the combustion gas distribution means ring member 22 can be maintained under the same conditions for a long period of time, which prolongs the life of the device and reduces the gas as a result it is possible to prevent the leakage can be prevented an increase of improvement and No _x generation of radiation efficiency. Further, the porous member can function as a combustion surface in almost the entire area of the front surface thereof, which also improves the thermal efficiency. Further, since the surface of the fixing means, which is the screw member, is covered with the heat-resistant adhesive, it is possible to prevent ignition in the gas mixing chamber due to heat transfer from the screw member, that is, occurrence of flashback.

Further, since the screw coupling is used as the fixing means for integrally fixing the porous member, the packing and the combustion gas distribution means, the screw engagement can be released by removing the surrounding adhesive. As a result, it becomes possible to replace the porous member and the heat-resistant packing, which are easily damaged, as needed, which facilitates maintenance and, as a result, prolongs the life of the burner.

The above description based on the drawings is a description of a preferred embodiment, and there are many other modified examples. For example, as the fixing means for integrally fixing the porous member, the packing and the combustion gas distribution means, the one having the screw coupling means is shown in the figure, but an appropriate fixing means such as riveting can be used. is there. However, in that case, it becomes difficult to replace the constituent members of the burner.

Further, although not particularly shown, a wall pressure part is provided in a part of the casing, a screw hole is formed in that part, and the porous member and the packing are screw-engaged using the screw hole. But it's good. In the above embodiment, the mixed gas chamber has the above-mentioned circulation path 26 defined by the annular member 22 constituting the combustion gas distribution means 20 and the casing 13, and the flat porous member 11 and the baffle plate. The front mixed gas chamber 41 is divided by 21 and the rear mixed gas chamber 42 is divided by the baffle plate 21 and the back plate 30. However, this is only one example. It will be easily understood that any shape conventionally known can be used as long as the shape can be fed from the open front end side of the member forming the casing. ..

[0025]

Since the surface combustion burner according to the present invention is configured as described above, deformation of the casing due to heat can be prevented, which can prevent leakage of the combustion gas mixture and prolong the life of the burner itself. At the same time, the reduction of radiation efficiency is prevented and the generation of No _x is reduced. In addition, depending on the mode of implementation, it is possible to replace easily damaged members such as porous materials and packing, which also extends the life of the burner itself.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of a surface combustion burner according to the present invention.

FIG. 2 is a sectional view showing a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Surface combustion burner, 2 ... Casing, 3 ... Casing bottom, 4 ... Open hole, 50 ... Screw, 11 ... Porous material, 1
2 ... Packing, 20 ... Combustion gas distribution means

Claims (2)

[Scope of utility model registration request] 1. A porous member having a combustion surface on its front surface,
A casing extending rearward from the rear surface near the outer periphery of the porous member, a mixed gas chamber formed by the porous member and the casing, and an opening for supplying a combustion gas mixture to the mixed gas chamber. In the surface combustion burner having the porous member, the porous member is attached to the casing or a member arranged in the casing by a suitable fixing means while exposing substantially the entire front surface of the porous member. A surface-combustion burner characterized in that the surface thereof is coated with a heat-resistant adhesive. 2. The surface combustion burner according to claim 1, wherein said fixing means is a fixing means by screw connection.