JPH0229376Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention provides a pulse combustion device, more specifically, a pulse combustion device, in which combustion air is supplied to the upstream side of an explosion combustion chamber through a valve mechanism for preventing backflow of explosion combustion gas from the combustion chamber. A supply path and a fuel gas supply path are provided in series, and an exhaust path is provided downstream of the explosion combustion chamber for discharging the explosive combustion gas from the combustion chamber by its explosive force, so that the explosion combustion chamber Using the suction force generated based on the exhaust kinetic inertia of the combustion gas after explosive combustion of the gas-air mixture, the fuel gas and combustion air are flowed into the combustion chamber and mixed, and part of the exhaust combustion gas is The pulse is configured to continuously repeat an explosive combustion cycle in which the gas-air mixture is explosively combusted by causing the gas to flow back from the exhaust passage into the combustion chamber, thereby causing the gas-air mixture to explode and burn with the heat retained in the backflowing combustion gas. Regarding combustion equipment.

Such pulse combustion equipment does not require energy for supplying combustion air or ignition other than when starting up, allowing for energy-saving operation.Also, since it is capable of high-load combustion, the equipment itself is compact considering its capacity. In addition, since the exhaust pressure of the combustion gas is high due to the explosive combustion mode, high-speed exhaust is possible even though the exhaust path is configured to be very narrow. Therefore, for example, the exhaust path can be configured with a thin tail pipe. In addition, extremely high heating efficiency can be obtained when it is used as an immersion pipe for heating fluids, and furthermore,
Immediately before explosive combustion, a portion of the combustion gas flows back into the combustion chamber from the exhaust passage, resulting in the so-called exhaust gas recirculation combustion mode occurring naturally, making low NOx combustion possible. It has various advantages such as.

However, various problems still remain in putting such a pulse combustion device into practical use. One of the problems is that, of the two backflow prevention valve mechanisms, the valve body in the backflow prevention valve mechanism for the combustion air supply path, which has to have a larger cross-sectional area than the fuel gas supply path, is very short-lived. There was a problem with it breaking over time.

In other words, in the conventional pulse combustion device, as shown in FIGS. 7 and 8, an air introduction portion is provided at the periphery of the valve mechanism 04 that prevents gas backflow from the explosion combustion chamber 01 to the combustion air supply path 03. A valve seat 04 equipped with a plurality of relatively large through holes 04a...
A, and a plurality of relatively large through holes 04 for allowing explosive combustion gas from the combustion chamber 01 to flow into the peripheral portion.
b..., and a large through hole 04c in the center for mainly introducing combustion air into the combustion chamber 01.
A catch seat 04B equipped with a seat 04B is connected to the seat 04B at an appropriate distance by a connecting member 04C..., and is moved back and forth between the two 04A and 04B as the explosion and combustion cycle is repeated within the combustion chamber 01. By this, the ring-shaped valve body 04 closes and opens the through hole 04a which is the air introduction part of the valve seat 04A.
It was constructed by interposing D. Thus, the valve body 04D is in contact with the catch seat 0 during its backflow prevention function.
Through the holes 04b, 04c, . . . of the valve 4B, it receives a powerful blast wave accompanying explosive combustion within the combustion chamber 01, and violently collides with the valve seat 04A. At that time, valve seat 04A
Each relatively large through hole 04 serves as an air introduction part.
Each part of the valve body 04D for a... deforms so as to fit into each of the through holes 04a..., and the valve body 04D corresponding to the edge of each through hole 04a...
Each part is subjected to extremely strong shear forces. and,
Since such a phenomenon is repeated for each explosion/combustion cycle (generally 60 to 70 times), the valve body 04D will tear or become punctured at an early stage, impairing its backflow prevention function.

The present invention was developed in view of the above-mentioned circumstances, and its purpose is to prevent the valve body from being partially exposed to concentrated force from the valve seat even if the valve body violently collides with the valve seat due to explosive combustion. The purpose is to significantly improve the durability of the valve body by preventing it from being exposed to water.

The characteristic configuration of the present invention is that, in a valve mechanism that prevents the backflow of explosive combustion gas to the combustion air supply path, the valve seat is formed of a porous wall body, and the air intake path that is opened and closed by the valve body is It is formed by the pores of a porous wall, and its effects are as follows.

In other words, combustion air is sucked into the explosion combustion chamber through the pores of the porous wall that forms the valve seat by the suction force due to the exhaust kinetic inertia of the combustion gas, and during explosive combustion, the valve body moves to the valve seat. is pressed by gas pressure,
The air intake channel, which consists of pores in the porous wall, is closed by a valve body to prevent the explosive combustion gases from flowing back into the combustion air supply channel.

Therefore, when the valve body collides with the valve seat, the portions of the valve body facing the pores can be dispersed over the entire surface of the valve body, and each of the portions facing the pores can be made to have an extremely small area. In other words, the valve body is evenly received over the entire surface by the valve seat, and the stress on the valve body caused by collision with the valve seat can be dispersed and extremely reduced. As a result, damage caused by collision of the valve body with the valve seat when the valve is closed can be effectively suppressed, and the durability of the valve body can be sufficiently improved compared to the above-mentioned prior art.

As a result, it has become possible to sufficiently improve the durability of the pulse combustion device and provide a pulse combustion device that is excellent in practical terms.

Examples of the present invention are shown in the drawings (Figs. 1 to 6) below.
The explanation will be based on Figure).

As shown in the first embodiment of FIGS. 1 and 2, an explosion combustion chamber 1 having a starting spark plug 10
A combustion air supply path 3 equipped with an electric fan 2 is connected to the upstream side of the combustion chamber 1 via a valve mechanism 4 called an air flapper for preventing the backflow of explosive combustion gas from the combustion chamber 1. A fuel gas distributor 5 is provided immediately downstream of the backflow prevention valve mechanism 4, and the gas distributor 5
A fuel gas supply path 8 having a flow rate regulating valve 7 is connected to the combustion chamber 1 via a valve mechanism 6 called a gas flapper for preventing the backflow of the explosion combustion gas from the combustion chamber 1. A straight tail pipe forming an exhaust path 9 for discharging explosive combustion gas from the combustion chamber 1 by its explosive force is connected to the side, thereby forming a pulse combustion device.

As shown in FIG. 2, the backflow prevention valve mechanism 4 for the combustion air supply path 3 has a porous structure as wide as possible as an air introduction section near the circumference of the disc-shaped valve seat 4A. A ring-shaped seat 4B is fitted with a ring-shaped wall 4a made of sintered metal and has a central through-hole 4c, and a plurality of through-holes 4 are formed around the entire circumference of the ring-shaped seat 4B.
b... are arranged side by side, and the catch 4B is integrally connected with the valve seat 4A while being separated from the valve seat 4A by a large number of bolt-nut-shaped connecting members 4C..., and the valve seat 4A and the catch 4B are A ring-shaped sliding valve body 4D is provided in between and positioned in the radial direction using the connecting member 4C.
When the pressure becomes positive, the pressing force acting on the valve body 4D from the center through hole 4c and the peripheral through hole 4b of the catch seat 4B presses the valve body 4D against the valve seat 4A, closing the valve mechanism 4 and closing the combustion chamber. 1 to the air supply path 3, and conversely, when the combustion chamber 1 becomes negative pressure after explosive combustion, it acts from the central through hole 4c and the peripheral through hole 4b of the seat 4B... The valve body 4D is moved from the valve seat 4A side to the catch seat 4B side by suction force to open the valve mechanism 4, and the pores of the porous sintered metal annular wall 4a of the valve seat 4A are formed. The combustion air is drawn into the explosion combustion chamber 1 through the air suction passage.

Next, the operation of the pulse combustion device will be explained.

At startup, the electric fan 2 is operated to supply fuel gas and combustion air to the combustion chamber 1 at an appropriate mixing ratio, and an explosion is caused within the combustion chamber 1 by the spark plug 10. Then, by using the negative pressure suction force generated in the combustion chamber 1 based on the exhaust kinetic inertia of the combustion gas after explosive combustion of the gas-air mixture in the combustion chamber 1, the fuel gas and the combustion air are removed. is mixed in an appropriate amount into the combustion chamber 1 via the backflow prevention valve mechanisms 4 and 6, and a part of the exhaust combustion gas is caused to flow back into the combustion chamber 1 from the exhaust passage 9. Then, the gas-air mixture is explosively combusted again using the heat retained in the backflowing combustion gas, and the explosion-combustion cycle is continuously repeated.

Note that the operation of the electric fan 2 and the spark plug 10 is stopped when pulse combustion becomes stable.

The pulse combustion device according to the present invention can be used for various heating purposes, such as heating a fluid by locating a tail pipe constituting the exhaust passage 9 in the fluid, or
It can be used for purposes such as utilizing exhaust energy.

3 and 4 show a second embodiment, in which a wall body 4a made of porous sintered metal with as large an area as possible is fitted into the center of a valve seat 4A to form an air introduction part. , the valve body 4D is formed into a disk without a through hole, and the seat 4B is formed to have a small diameter.

FIGS. 5A and 5B show another embodiment, and FIG. 5A shows the valve seat 4A in the first embodiment shown in FIGS. The wall body 4a is made of high quality sintered metal and is integrally manufactured, and a coating 4d is applied to the surface of the outer peripheral part and the central part other than the air introduction part to make it impossible to ventilate. FIG. 5B shows that the valve seat 4A in the second embodiment shown in FIGS. 3 and 4 is similarly integrally constructed with a porous sintered metal wall 4a, and its outer peripheral portion is A coating 4d is applied to the inner surface, and the center portion is used as an air introduction portion.

FIGS. 6A and 6B show still another embodiment, in which the valve seats 4A and 4 in the first and second embodiments, respectively, are shown.
A is constructed of only an iron plate, and a large number of extremely fine holes 4e are bored as air introduction portions.

Further, as another embodiment, the porous wall body 4a may be constructed using ceramic foam, hard asbestos, extremely fine mesh wire mesh, punched metal, etc. instead of the porous sintered metal. In short, the valve seat 4A and its air suction path may be constructed of a porous wall 4a having fine holes.

The pressure loss due to the valve seat 4A shown in each of the above embodiments can be made to be the same as that of a conventional valve seat by selecting the thickness of the porous wall 4a and the distribution density of micropores. The design is such that there are no combustibility problems.

[Brief explanation of the drawing]

1 and 2 show a first embodiment of the present invention, FIG. 1 is a schematic vertical sectional view of a pulse combustion device, FIG. 2 is an exploded perspective view of the main parts, and FIGS. The figure shows a schematic vertical sectional view and an exploded perspective view of the main parts of the second embodiment, and FIGS. Moreover, FIGS. 7 and 8 are a schematic vertical sectional view and an exploded perspective view of essential parts showing a conventional configuration. 1... Explosion combustion chamber, 3... Combustion air supply path,
4, 6... Valve mechanism for backflow prevention, 8... Fuel gas supply path, 9... Exhaust path, 4A... Valve seat of 4, 4a...
... Porous wall body, 4D... Valve body.

Claims (1)

[Scope of claim for utility model registration] 1. On the upstream side of the explosion combustion chamber 1, the explosion combustion chamber 1
A combustion air supply path 3 and a fuel gas supply path 8 are connected to each other via valve mechanisms 4 and 6 for preventing backflow of explosion combustion gas from the explosion combustion chamber 1, and on the downstream side of the explosion combustion chamber 1, An exhaust passage 9 for discharging the explosive combustion gas from the explosion combustion chamber 1 by its explosive force is provided in series, so that the combustion gas is discharged by the dynamic inertia after the explosive combustion of the gas-air mixture in the explosion combustion chamber 1. By causing fuel gas and combustion air to flow into the explosion combustion chamber 1 using suction force, and by causing a part of the exhaust combustion gas to flow back into the explosion combustion chamber 1 from the exhaust passage 9, the backflow combustion gas is A pulse combustion device configured to explosively burn a gas-air mixture using retained heat and to continuously repeat an explosive combustion cycle, wherein the explosion combustion gas is prevented from flowing back into the combustion air supply path 3. In the valve mechanism 4 that prevents pulse combustion, the valve seat 4A is formed by a porous wall 4a, and the air suction passage opened and closed by the valve body 4D is formed by the pores of the porous wall 4a. Device. 2. The pulse combustion device according to claim 1, wherein the porous wall body 4a is made of porous sintered metal.