JPH0229403Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a combustion type heater such as an kerosene stove that performs heating using the heat of combustion gas.

(Conventional technology) Combustion type heaters that use fuels such as oil and gas have the problem of emitting bad odors and harmful gases due to unburned gas immediately after ignition and extinguishing, so in order to reduce this odor and CO generation, , a heater with a catalyst installed inside the device is provided, part 1.
An example is disclosed in Japanese Utility Model Publication No. 54-44277.

The heater is equipped with a catalyst tank in the combustion cylinder, which has a smaller diameter than the combustion cylinder and has a catalyst layer inside, at a predetermined distance from the inner wall of the combustion cylinder, and between the catalyst tank, the combustion cylinder, and the wall. The structure is equipped with a guide tube that guides gas to the catalyst layer, and when the combustion gas rises in the combustion tube, it is guided by the guide tube and all flows into the catalyst tank and is purified in the process of rising. is forming.

(Problem to be solved by the invention) However, the above-mentioned heater inevitably becomes complicated, as the catalyst tank must be attached to the combustion cylinder in a double-tube structure, and members for fixing it are required. In addition, as catalyst vessels, parts such as woven silica fiber coated with catalyst or ceramic honeycomb-shaped parts coated with catalyst on the surface are used, resulting in complex shapes. , which had the disadvantage of increasing equipment costs.

Moreover, since the upper half of the combustion cylinder has a double cylinder structure with the catalyst tank as the inner cylinder, the surface of the combustion cylinder does not become red hot, which reduces the radiation intensity and reduces the amount of heat radiated. There was a problem with heating efficiency becoming poor.

Focusing on the fact that conventional heaters have various drawbacks, the present invention was developed to solve these problems. This improves the contact with the gas to be treated and further promotes the oxidation action of the catalyst, and also improves the overall structure of the combustion tube, especially the holes for passage of combustion gas, to further improve radiation efficiency. The scale is an attempt to realize high-efficiency heating.

(Means for Solving the Problems) Accordingly, the present invention provides a combustion type heater having a combustion tube in which a peripheral wall is provided with a large number of holes for passage of combustion gas, in which an eave-like wall 10 is provided in each of the holes. A catalyst layer is formed on the outer surface or inner surface of the peripheral wall of the combustion cylinder, or on both the inner and outer surfaces of the peripheral wall of the combustion cylinder.

Note that the carrier layer in this case is a layer equivalent to an ultrathin film such as silica or alumina;
A small amount of platinum is used as the catalyst metal, and the catalyst layer as a whole is formed into a thin layer of about 1 μm.

(Function) With the above configuration, the combustion gas passing through the holes once blows against the canopy-shaped wall in each hole, passes through the holes, rises along the peripheral wall surface, and hits the outer wall of the combustion tube. Forms a thick layer of high temperature air.

Further, since the catalyst layer is present around each hole, the contact between the combustion gas and the catalyst is extremely good, and the oxidation of the combustion gas is further promoted.

The former, heating by the high-temperature air layer, and the latter, promotion of oxidation, combine to promote red heat in the combustion tube, resulting in a large radiation efficiency.

(Embodiments) Hereinafter, embodiments of the present invention will be further described in detail based on the accompanying drawings.

Fig. 1 schematically shows the combustion section of a kerosene stove according to one example of the present invention, and 1 is a combustion tube consisting of a stepped vertical tube with a small diameter tube connected at the top and a large diameter tube connected at the bottom. The top of the small-diameter cylinder is covered with a top plate, and the large-diameter cylinder is erected in the glass cylinder 3 with the burner flame opening 2 covering it.

Note that the structure may be such that the glass tube 3 is omitted.

The peripheral wall of the small-diameter cylinder that occupies most of the combustion cylinder 1 is provided with a large number of holes 4 for releasing high-temperature gas to the outside of the cylinder after combustion at the burner flame port 2.
As a feature of the present invention, these holes 4 have an eave-like wall 10 at their upper end, opening diagonally downward, as if they were windows with an "eaves."

Incidentally, a cylinder having such a hole 4 can be easily formed by using a metal lath-like plate shown in FIGS. 2A and 2B as a material.

For example, in the example shown in Figure 2, slits of 5 to 10 mm are made in a thin metal plate approximately 0.8 mm thick in a staggered arrangement at fine pitches, and the so-called cut-and-raise is performed by bending the metal plate to both sides along the slits. For example, a metal lath-like plate having a large number of flat diamond-shaped or leaf-shaped holes 4 with a horizontal pitch of 15 mm and a vertical pitch of 4 mm in a staggered arrangement is formed, and this is rounded. By molding it into a cylinder, the combustion cylinder 1 having a large number of holes 4 with eaves-like walls 10 as described above is formed.

Further, the combustion tube 1 is coated with a catalyst layer 5 on the outer surface or inner surface of its peripheral wall or on both inner and outer surfaces thereof.

As shown in an enlarged cross section in FIG. 3, this catalyst layer 5 is formed into a thin film of about 1 to 2 μm by coating it with a support layer such as alumina, which supports a small amount of platinum in a highly dispersed state. The metal lath-like plate is first coated with a carrier such as alumina or silica, and then platinum is dispersed in this carrier layer by a process such as vapor deposition. By carrying out the supporting process, processing can be performed easily and continuously.

However, in the combustion type heater configured in this way, the high-temperature gas burned at the burner flame port 2 rises inside the combustion tube 1 and exits the tube 1 through the hole 4. The air blows onto the eave-like wall 10 of the hole 4 through the lower end of the eave-like wall 10.
and rises along the surrounding wall surface. Therefore, efficient heating is performed, and a thick layer of high temperature air is formed around the outer wall, which promotes red heat in the combustion tube 1.

Moreover, the high-temperature gas at this time comes into contact with the catalyst layer present on the peripheral wall of the combustion tube 1, but this catalyst layer is also formed on the eaves-shaped wall 10, so the contact area between the high-temperature gas and the catalyst is large. , a highly active catalytic action is performed, and carbon monoxide (CO) and hydrocarbons (HC) in the combustion gas are effectively converted into carbon dioxide (CO ₂ ) and water (H ₂ O), resulting in an efficient process. Gas purification and deodorization are performed. Furthermore, this oxidation action promotes combustion of the combustion gas, further promoting red heat in the combustion tube 1 described above, and achieving an improvement in radiation efficiency.

(Effects of the invention) As described above, the combustion type heater according to the invention has a large number of holes in the combustion tube that have eave-shaped walls and open diagonally downward, so that combustion gas flows through these holes. As it passes through, it efficiently heats the peripheral wall of the combustion tube and creates a thick layer of high temperature air along the outer wall, promoting red heat in the combustion tube.

In addition, since a catalyst layer is formed on the peripheral wall of the combustion cylinder, the combustion gas passing through the holes can directly
It comes into contact with the catalyst layer over a wide area, performs efficient catalytic action, ensures gas purification and deodorization, and promotes oxidation of the combustion gas.This oxidation promotion further heats the combustion tube. The red heat of the combustion tube described above will be further promoted.

Needless to say, this improves radiation efficiency and realizes highly efficient heating.

Moreover, the above-mentioned combustion type heater does not require a separate special material when forming the catalyst layer, and moreover,
A catalyst tank for bringing combustion gas into contact with a catalyst layer,
A guide device is not required, and the structure can be simpler than that of a conventional catalyst tank, which is advantageous in terms of cost reduction.

[Brief explanation of the drawing]

Fig. 1 is a structural diagram of the main parts of a kerosene stove according to an example of the present invention, Fig. 2 is a partially enlarged front view of the combustion cylinder peripheral wall in Fig. A sectional view taken along the line A-A, and FIG. 3 is a partially enlarged sectional view of the combustion tube in FIG. 1. 1... Combustion tube, 4... Hole, 5... Catalyst layer, 10
...Eave shaped wall.

Claims (1)

[Scope of utility model registration request] In a combustion type heater having a combustion cylinder 1 in which a plurality of holes 4 for passing combustion gas are provided in the peripheral wall, each hole 4 is provided with an eave-like wall 10 to open obliquely downward, and a catalytic metal A catalyst layer 5 formed by supporting in a highly dispersed manner in a carrier layer,
A combustion type heater characterized in that it is formed on the outer surface, inner surface, or both inner and outer surfaces of the peripheral wall of the combustion tube 1.