WO2013088978A1

WO2013088978A1 - Muffler having helical muffler element as alternative to oxidation catalyst

Info

Publication number: WO2013088978A1
Application number: PCT/JP2012/081224
Authority: WO
Inventors: 勇奥野; 慎太郎奥野
Original assignee: Okuno Isamu; Okuno Shintaro
Priority date: 2011-12-12
Filing date: 2012-11-26
Publication date: 2013-06-20
Also published as: JP2015038324A

Abstract

In order to separate CO contained in exhaust gas in an internal combustion engine into C and O not by a chemical change caused by a catalyst but physically, a muffler comprises an external cylinder which is inserted in the muffler of an internal combustion engine and has an inlet hole formed on the upstream side and an outlet hole formed on the downstream side, and houses, within the external cylinder, a helical muffler element which is configured by securing a tapered conical body by a plurality of plate-shaped helical stays with the starting end and ending end thereof facing a radial direction and the middle part thereof twisted more strongly toward the peripheral end thereof between the conical body and the external cylinder. When flow paths separated by the helical stays are viewed from the front, the flow paths are each twisted to such a degree that the ending end thereof is hidden by the helical stay adjacent thereto and cannot be viewed, and the twist angle is set larger at the outer end of the helical stay than the inner end thereof.

Description

A muffler with a helical muffler element instead of an oxidation catalyst

The present invention reduces harmful substances that are not good for the human body and the environment contained in exhaust gas discharged from an internal combustion engine using gasoline or diesel as fuel, and also improves fuel efficiency by reducing the exhaust pressure of the engine and its own exhaust pressure. The present invention relates to a muffler having a helical muffler element instead of the oxidation catalyst to be produced.

The exhaust gas from internal combustion engines (hereinafter referred to as engines) that burn gasoline, diesel, etc. contains harmful substances such as carbon dioxide (CO ₂ ), hydrocarbons (HC), and nitrogen oxides (NOx). However, carbon monoxide (CO) and oxygen (O ₂ ) are also included. Among these, since CO is very toxic, an oxidation catalyst (hereinafter referred to as catalyst) is inserted into a muffler that leads to exhaust gas, and this is changed into CO ₂ and discharged. The principle of the catalyst is to generate oxygen at a high temperature of exhaust gas using rare metals such as platinum, palladium and rhodium and chemical substances such as potassium chlorate and manganese dioxide, and change CO to CO ₂ based on this oxygen. .
However, heat is required to generate oxygen, and for this purpose, the engine must be warmed to some extent and the exhaust gas must be hot. Therefore, it did not act effectively until the engine warmed up, and CO was discharged as it was. On the other hand, the engine warms, even changing the CO to CO _2, in turn, increased emissions of CO _2, which causes global warming has become a recent problem. Furthermore, there is a problem that the catalyst is expensive.
Therefore, if these harmful substances can be reduced without using a catalyst, it is not necessary to use limited resources and chemical substances. Therefore, the present inventor has tackled this problem, proposed the following Patent Documents 1 and 2, and has achieved the corresponding effects. Furthermore, it is known that when exhaust gas emission is promoted to reduce engine exhaust pressure, output is increased and fuel efficiency is improved, and as a result, harmful substances can be reduced. Something like this has also been proposed.

Japanese Patent No. 25551516 Japanese Patent No. 3344968 US Pat. No. 5,962,822

In the present invention, CO is not changed to CO ₂ by a chemical change caused by the catalyst, but is physically separated into C and O, so that the CO can be reduced without using the catalyst, and the amount of CO ₂ is also consequently increased. It can be reduced.

Under the above problems, the present invention has an outer cylinder that is inserted into the muffler of the internal combustion engine according to claim 1 and has an inlet hole formed on the upstream side and an outlet hole formed on the downstream side, A tapered cone in the outer cylinder is fixed with a plurality of plate-like spiral stays that are twisted so that the starting end and the terminal end are radially directed between the outer cylinder and the middle toward the end side. A muffler containing a spiral muffler element. When the flow path partitioned by a spiral stay is viewed from the front, the end is twisted to the extent that it is hidden behind the adjacent spiral stay and cannot be seen. The corner provides a muffler having a helical muffler element instead of an oxidation catalyst, characterized in that the outer end is set larger than the inner end of the helical stay.
According to the present invention, in the above-described muffler, the twisting degree described in claim 2 is a means in which the end of the outer end is shifted by about two phases from the starting end, and the maximum outer periphery of the cone according to claim 3 Means in which the total volume of the gap between the outer cylinder and the outer cylinder is larger than the volume of the entrance hole, eight or more spiral stays according to claim 4 are provided, and the cross-sectional area of the flow path goes downstream. According to a fifth aspect of the present invention, there is provided a means in which the gap between the inner periphery of the outer cylinder and the maximum outer diameter of the cone is set to about 15 mm ± 3 mm.

According to the first aspect of the present invention, the space defined by the spiral stay on the outer periphery of the conical body becomes an air flow path, and the flow path is considerably twisted, so that the exhaust gas flowing through the spiral muffler element Becomes a donut-shaped spiral flow (torsional flow) and is discharged into the space behind the element. At this time, since the torsion of the spiral stay is very large, it receives a large twisting force. As a result, the exhaust gas receives a centrifugal force, and by this centrifugal force, the coupling of CO is cut and separated into C and O, and the generated CO ₂ emission can also be reduced. In other words, the catalyst according to the first aspect is physically separated from the catalyst due to chemical change. In this respect, a catalyst is not required and the cost is low, and it functions even when the exhaust gas is at a low temperature.
The twist is preferably the extent of claim 2, and according to the configurations of

claims

3 and 4, the exhaust gas expands toward the rear of the flow path, promotes circulation, and exhibits a suction effect. According to the structure of Claim 5, the number of flow paths increases and it can receive more venturi effects.

It is side surface sectional drawing of a helical muffler element. It is side surface sectional drawing which shows the relationship between a cone and a stay. It is AA of FIG. It is BB sectional drawing of FIG. It is side surface sectional drawing of the other example of a helical muffler element. It is side surface sectional drawing of the other example of a helical muffler element. It is a perspective view of a spiral muffler element. It is a perspective view of a spiral muffler element. It is side surface sectional drawing of the other example of a helical muffler element. It is a graph which shows the relationship between the pressure and flow velocity of the muffler of the conventional example which uses the helical muffler element of this invention, and a catalyst.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side sectional view of a muffler (hereinafter referred to as muffler) having a spiral muffler element instead of an oxidation catalyst showing an example of the present invention, and FIG. 2 is a sectional view of a spiral muffler element (hereinafter referred to as element) constituting the muffler. 7 to 8 are perspective views of the element. The element is inserted into a muffler relatively close to the engine exhaust port, and is composed of an inlet fitting 1, an outer cylinder 2, and an outlet fitting 3 from the upstream side. However, among these, the inlet fitting 1 has a cylindrical shape extending from the mounting flange 5 in which the inlet hole 4 is formed to the outer cylinder 2, and the outer cylinder 2 is formed from the inlet fitting 1 (entrance hole 4). Is a pipe with a large diameter (6 is the front wall). The outlet fitting 3 is connected to the downstream side of the outer cylinder 2 and has a mounting flange 8 in which an outlet 7 having a relatively large cross-sectional area is formed.
An element 9 is accommodated in the outer cylinder 2 immediately after the front wall 6. The downstream side of the element 9 is a space 10 having a length that is at least equal to the width of the element 9. 3 is a cross-sectional view taken along the line AA of FIG. 1, and FIG. 4 is a cross-sectional view taken along the line BB. However, the element 9 becomes closer to the outer periphery of the cone 11 having a narrow upstream end and a large diameter on the downstream side. A plurality of plate-shaped radial spiral stays (hereinafter referred to as stays) 12 that are twisted are attached and fixed to the center of the outer cylinder 2 (in this example, the element 9 is prevented from shifting to the downstream side. Therefore, the sleeve 13 is inserted on the inner periphery of the outer cylinder 2). Since the diameter of the outer cylinder 2 is constant, the length of the stay 12 becomes lower toward the downstream side. At this time, a gap 14 is formed between the maximum outer circumference of the cone 11 and the outer cylinder 2, and the exhaust gas that has entered from the inlet 4 passes through the space 10 through the gap 10 and exits from the outlet 7. .
Between the outer periphery of the cone 11 and the outer cylinder 2, a flow path 15 separated by a stay 12 is formed. In the present invention, the stay 12, that is, the flow path 15 is twisted as far as it goes to the end. Specifically, the stay 12 is applied to a small vehicle to be described later. It is out of phase. For this reason, when the start end of a certain flow path 15 is viewed from the front, the end is hidden behind the adjacent stay 12 and cannot be seen (FIG. 3). However, since the start end and the end of the stay 12 are directed in the center direction (radial direction), the cross section of the stay 12 has a concave twisting direction. At this time, the torsion angle of the stay 12 is α at the outer end 12a (portion that contacts the outer cylinder 2), β at the inner end 12b (portion that contacts the cone 11), and α> β. That is, the degree of twisting is larger at the outer end 12a having a higher height than the inner end 12b. In view of this, the larger the number of stays 12, the better. However, since the flow path 15 must have a certain width, about 8 to 12 is preferable. As an example, what is applied to a small vehicle is that the number of stays 12 is 10, the outer diameter is 110 mm, the width is 60 mm, and the maximum outer circumference of the cone 11 is about 78 mm. In addition, there are also those with 12 stays 12 and an outer diameter of 136 mm that are applicable to medium-sized and large-sized vehicles (other sizes are correspondingly larger).
Since the stay 12, that is, the flow path 15 is largely twisted, the exhaust gas flowing through the flow path 15 is subjected to torsional rotation and receives centrifugal force. Due to this centrifugal force, CO in the exhaust gas is separated into C and O by weight difference, and is not discharged from the outlet 7 as CO. Separation by centrifugal force is promoted as the space 10 becomes longer. In addition, the entire volume of the gap 14 is larger than the volume of the inlet hole 4, and the exhaust gas that has entered from the inlet hole 4 is expanded until it exceeds the cone 11. Furthermore, it is preferable that the volume of the flow path 15 increases toward the end. That is, it is preferable from the viewpoint of facilitating discharge that the exhaust gas is gradually expanded until it enters from the entrance hole 4 and flows through each flow path 15 to pass through the gap 14 and enter the space 10.
As described above, the exhaust gas that has entered through the inlet hole 4 flows through the flow path 15. At this time, the stay 12 is largely twisted, and therefore the lengths of the stays are different on the front and back surfaces. Specifically, in this example, since it is twisted to the left when viewed from the front, the right side is longer than the left side, the exhaust gas flow rate is high, and the pressure is reduced. Therefore, the venturi effect is received in the flow path 15 and the circulation of the exhaust gas is promoted. As a result, the exhaust gas is sucked.
The exhaust gas will eventually exceed the gap 14, but the total volume of the gap 14 at this time is larger than the volume of the inlet hole 4, and in addition, the cross-sectional area gradually decreases toward the downstream side of the flow path 15. Since it is large, this suction effect is further promoted. However, the length of the gap 14 has a certain range, and as a result of testing by the inventor, it has been confirmed that about 15 mm ± 3 mm and optimally about 17 mm are suitable. If the gap 14 is too large, the exhaust gas spreads poorly and sufficient centrifugal force does not work. If it is too small, the absolute cross-sectional area of the gap 17 decreases and clogging occurs. Furthermore, it has been confirmed that this dimension hardly changes depending on the diameter of the outer cylinder 2.
FIG. 5 is a plan sectional view showing another example of the muffler using this element 9. In this example, the start end of the stay 12 of the element 9 and the end of itself are continuous in the inlet fitting 1. The element 17 is provided which is fixed by a stay 16 that is twisted by (a thin core material is provided at the center). According to this, since the degree of twisting becomes large and the flow path length becomes long, a larger venturi effect can be received.
FIG. 6 shows the outer cylinder 2 connected from the element 9 to a metal-net (lass) exhaust cylinder 18 and continued to the outlet fitting 3. This wire mesh is formed by cutting a thin iron plate and pulling it sideways to form a rhombus-shaped mesh. When the side is arranged on the outlet 7 side, exhaust gas is actively taken into the convex portion and the discharge is promoted. At the same time, HC adheres to the convex portion and burns at a high temperature of the exhaust gas. As a result, the amount of HC emission can be reduced.
FIG. 9 is a plan sectional view showing another example using this element 9. In this example, the inlet fitting 1 and the outlet fitting 3 are each tapered with a large diameter on the outer cylinder 2 side. It is. According to this, the exhaust gas suction effect is high, and the discharge is performed smoothly. Particularly, the taper on the outlet side facilitates the discharge and is effective in reducing its own discharge pressure.
FIG. 10 is a graph showing the relationship between the pressure and the flow velocity when a pressure gauge is placed in front of the cone 11 in the above-described basic type spiral element (product of the present invention). ), The pressure of the present invention is reduced compared to the increase of the inflow pressure as the flow rate increases. This proves that according to the muffler using the element 9 of the present invention, there is an exhaust effect of the exhaust gas of the engine, the exhaust pressure of the engine is reduced to prevent the output from being lowered, and the fuel consumption is also improved. (The above-described large-capacity space 10 also contributes to this suction effect).
The following is a table in which the Japan Automobile Transport Technology Association measured CO and CO ₂ in the exhaust gas discharged from the rear end of the muffler for the present invention product and the conventional product using the catalyst when idling in a medium-sized gasoline vehicle. .

Looking at this, CO is zero in the conventional product that uses a catalyst, but this is the value when the warm-up operation is sufficiently performed and the exhaust gas becomes high temperature, and until then, a considerably high amount of CO Is presumed to be discharged. On the other hand, although CO is slightly emitted in the product of the present invention, this level is not a problem and is far below the national standard value above all. Therefore, the product of the present invention is not affected by the temperature of the exhaust gas and has a feature that a catalyst is not required.
In addition, the amount of CO _{2 in} the product of the present invention is reduced compared to the conventional product. This is also a proof of separating CO into C and O by the centrifugal force described above. In the present inventions it slightly CO is discharged has been described above, even when added to this amount, it can be seen that has decreased than conventional product CO _2. This difference in CO ₂ is only measured in a short time during idling of one vehicle, but when the vehicle travels at a predetermined speed and distance, the total difference becomes enormous.
As a result of the test conducted by the inventor on a medium-sized vehicle, the product according to the present invention has a result that CO ₂ is reduced by 1.25 g at 1 Km compared to the conventional product. It will be reduced by 5t. Furthermore, traveling bodies such as vehicles equipped with a large number of engines are running on the earth, and the present invention is applied to all of them.

The above is mainly described with respect to automobile mufflers, but the present invention is not limited to these, and agricultural machinery such as ships, aircraft, tractors, etc. equipped with engines fueled with hydrocarbons such as gasoline and diesel, It can be applied to all mufflers of internal combustion engines applied to other traveling bodies.

Claims

Inserted into the muffler of the internal combustion engine, has an outer cylinder with an inlet hole formed on the upstream side and an outlet hole formed on the downstream side, and a tapered cone in the outer cylinder between the outer cylinder A muffler that accommodates a spiral muffler element fixed by a plurality of plate-like helical stays that are twisted as the start and end points in the radial direction and go to the peripheral side in the middle, separated by a helical stay When the flow path is viewed from the front, the end is twisted so that it is hidden behind the adjacent spiral stay, and the torsion angle is larger at the outer end than at the inner end of the spiral stay. A muffler having a helical muffler element instead of an oxidation catalyst characterized by being set.
The muffler having a spiral muffler element instead of the oxidation catalyst according to claim 1, wherein the degree of twisting is about two phases at the end of the outer end with respect to the start end.
3. A muffler having a spiral muffler element instead of the oxidation catalyst according to claim 1 or 2, wherein the entire volume of the gap between the maximum outer periphery of the cone and the outer cylinder is larger than the volume of the inlet.
A muffler having a spiral muffler element instead of the oxidation catalyst according to any one of claims 1 to 3, wherein eight or more helical stays are provided, and the cross-sectional area of the flow path gradually increases toward the downstream side.
5. A muffler having a spiral muffler element in place of the oxidation catalyst according to any one of claims 1 to 4, wherein a gap between the inner periphery of the outer cylinder and the maximum outer diameter of the cone is set to about 15 mm ± 3 mm.