JPS645049Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an out-of-cylinder explosion prevention device for an engine, and provides one that maintains exhaust resistance low, does not reduce engine output, and has a simple structure.

Generally, when unburned gas is discharged into a muffler that is heated to a high temperature, an explosion occurs within the muffler.
In addition to damaging the muffler, there was a risk that flames would blow out from the muffler outlet pipe, causing burns to workers, or spreading to straw and dust floating around the work equipment.

In particular, when the engine is used for a pump set or generator, if the engine is suddenly stopped while operating at high speeds and under high load, a large amount of unburned gas in the combustion chamber may be discharged into the muffler. Ta.

Conventionally, methods for preventing the above-mentioned out-of-cylinder explosion have included a structure that cuts off fuel cut or ignition at the time of overlap, but this complicates the mechanism and increases costs.

In addition, a structure is adopted in which a flame extinguishing device made of steel wool or the like is installed near the exhaust port or the exhaust port of the muffler inlet pipe, but this reduces the cross-sectional area of exhaust gas passage and increases exhaust resistance, resulting in lower engine output. This causes a decrease in Moreover, in this configuration,
Since it is necessary to cover the exterior of the device with a protective cover to prevent workers from coming into contact with this part and sustaining burns, there is a problem in that the overall size of the device increases.

The present invention aims to solve the above-mentioned problems, and to exhibit a flame-extinguishing function without increasing exhaust resistance, and to simplify the entire device by omitting a protective cover and the like.

In order to achieve the above object, the present invention has an external explosion device configured as shown in FIGS. 1 to 6, for example.

That is, the inlet pipe 3 of the muffler 2 is connected to the exhaust port 1 of the engine E, the inlet pipe 3 is connected to the muffler body 4 of the muffler 2, and the terminal end 5 of the inlet pipe 3 is connected within the muffler body 4 with a diameter larger than that. The inlet 7 of the flame extinguishing tube 6 is communicated with the inlet 7 of the flame extinguishing cylinder 6.

Then, outlet holes 10 are formed at multiple locations in the peripheral wall 8 of the flame extinguishing tube 6, and the inlet pipe 3 is connected to the exhaust inlet chamber 22 in the muffler body 4 through the flame extinguishing tube inlet 7, the flame extinguishing tube 6, and the flame extinguishing tube outlet hole 10. A breathable flame extinguisher 12 is installed inside the flame extinguisher 6.

Hereinafter, the effects of the present invention achieved by the above configuration will be described. First, the flame extinguishing cylinder is made larger in diameter than the terminal end of the muffler inlet pipe, and a breathable flame extinguisher is installed inside it, so that the cross-sectional area of the exhaust gas is It is possible to secure a large amount of
It is possible to maintain low exhaust resistance and suppress a drop in engine output.

In addition, since the flame extinguishing cylinder is connected to the terminal end of the inlet pipe housed in the muffler, there is no need to attach a protective cover around the flame extinguishing cylinder to prevent contact with the operator.
The muffler itself can also be used as a protective cover, simplifying the structure. Furthermore, since the structure is simple, just attaching a large-diameter flame extinguishing tube to the muffler inlet pipe, it can be implemented at low cost, and can be easily applied to existing mufflers with only slight additional processing.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a side valve air-cooled engine, FIG. 2 is a front view of a muffler, FIG. 3 is a cutaway left side view of the main part, FIG. 4 is a cross-sectional view of FIG. 3, and FIG. 5 is a longitudinal front view of the muffler.
A cooling fan and an air guide case 14 are provided on the front surface of the
A recoil starter 15 attached to the air guide case 14
When the fan is pulled, the rotation of the cooling fan causes outside air to be drawn into the engine through an outside air intake 16 on the side of the air guide case, and this outside air is guided by the air guide case 14 and blown against a cylinder 17 to air-cool the engine.

The engine E has an air cleaner 18 disposed in front of its left side wall and connected to an intake port 19,
A muffler 2 is arranged behind the left side wall and its inlet pipe 3 is connected to the exhaust port 1.

The muffler 2 is composed of a muffler main body 4 and a muffler cover 20, and the half cover parts 20a are fitted to each other so as to cover the muffler main body 4, and the muffler cover 20 is externally fitted to the muffler main body 4.

The muffler body 4 has a porous partition plate 2 inside.
1 to form an exhaust inlet chamber 22, a buffer chamber 23, and an exhaust outlet chamber 24 from above.

The terminal end 5 of the inlet pipe 3 protrudes into the exhaust inlet chamber 22, and a flame extinguishing tube 6 having an inner diameter larger than the outer diameter of the inlet pipe is fitted into the terminal end 5.

The flame-extinguishing cylinder 6 is made by cutting and raising the upper end of each part in the circumferential direction into four equal parts to form a support part 28, and by bending the support part 28 in a direction perpendicular to the cylinder direction, the end part of the inlet pipe is formed. 5 and supports it (see Figure 6).

Further, the flame extinguishing cylinder 6 has its lower end cut into an inclined shape so as to be in contact with the side wall of the exhaust inlet chamber 22, and the lower end is closed with a blind plate 29, and a breathable flame extinguisher 12 is inserted in the flame extinguishing cylinder. The top and bottom are supported by a support section 28 and a blind plate 29, respectively.

The flame extinguishing cylinder 6 has an inlet 7 in the gap between the supporting parts 28 provided above, and has multiple holes in the peripheral wall 8 as outlet holes 10 to allow the exhaust gas entering from the inlet 7 to pass through the flame extinguisher 12. Afterwards, it is formed so as to be discharged from the exit hole 10.

The flame extinguishing tool 12 is formed by inserting steel wool or the like along the length of the flame extinguishing cylinder so as to maintain a small exhaust resistance.

Further, an outlet pipe 25 is provided in the exhaust outlet chamber 24 of the muffler body 4, and exhaust gas is discharged from a through hole 26 formed in the peripheral wall of the outlet pipe 25 to a lower outlet 27.

On the other hand, the muffler cover 20 has an opening in its upper side wall to lead out the inlet pipe 3, and a guide cylinder 30 is provided below the opening, into which the muffler outlet pipe 25 is inserted.

Even when the exhaust gas contains unburned gas, the out-of-cylinder explosion prevention device thus constructed removes its own heat from the exhaust gas by the flame extinguisher 12 in the flame extinguishing cylinder 6, so that the temperature of the gas is reduced. By lowering the temperature to a temperature condition outside the explosion range, it is possible to prevent unburned gas from causing an out-of-cylinder explosion.

Moreover, since the diameter of the flame extinguishing cylinder 6 is set to be larger than that of the inlet pipe 3, the cross-sectional area through which exhaust gas passes can be increased, and a smooth flow of exhaust gas can be ensured.

Therefore, the exhaust gas whose sound has been muffled by the muffler passes through the partition plate 21 and enters the buffer chamber 23 and the exhaust outlet chamber 24.
After being muffled, the air is discharged from the outlet pipe 27 to the atmosphere.

In addition, in the above practical example, since the support part provided integrally with the muffler performs the pressing function of the muffler, the structure of the entire device can be further simplified; however, this is not limited to this example, and it is possible to A supporting portion may be attached to press the muffling device and may also be configured to receive the terminal end of the inlet pipe.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is a perspective view of a side valve air-cooled engine, Fig. 2 is a front view of the muffler, Fig. 3 is a cutaway left side view of the main part thereof, and Fig. 4 is a perspective view of the side valve air-cooled engine. FIG. 3 is a sectional view taken along the line --, FIG. 5 is a vertical sectional front view of the muffler, and FIG. 6 is a perspective view of the main parts of the flame extinguishing tube. DESCRIPTION OF SYMBOLS 1...Exhaust port, 2...Muffler, 3...Inlet pipe, 4...Muffler body, 5...Terminal part of 3, 6...
...Flame extinguisher, 7...Inlet of 6, 8...Surrounding wall of 6, 1
0... Exit hole of 6, 12... Flame extinguisher, 22... Exhaust inlet chamber, 28... Support part, 29... Blind plate, E...
…engine.

Claims (1)

[Claims for Utility Model Registration] 1. The inlet pipe 3 of the muffler 2 is connected to the exhaust port 1 of the engine E, the inlet pipe 3 is connected to the muffler body 4 of the muffler 2, and the terminal end of the inlet pipe 3 is connected within the muffler body 4. The inlet 7 of a flame extinguishing tube 6 having a larger diameter is communicated with the section 5, and outlet holes 1 are provided at multiple locations on the peripheral wall 8 of the flame extinguishing tube 6.
0, and connect the inlet pipe 3 to the muffler body 4 through the flame extinguishing tube inlet 7, the flame extinguishing tube 6, and the flame extinguishing tube outlet hole 10.
This outside explosion prevention device for an engine is characterized in that a breathable flame extinguishing device 12 is installed inside a flame extinguishing tube 6, communicating with an exhaust inlet chamber 22 inside. 2. In the engine out-of-cylinder explosion prevention device set forth in claim 1 of the utility model registration claim, the flame extinguishing cylinder 6
Cut and raise the upper end of the support part 2 inward at multiple points.
8, the terminal end 5 of the inlet pipe 3 is fitted into the flame extinguishing cylinder 6 and received by the support part 28, and the flame extinguishing cylinder 6
A flame extinguisher 12 is supported between a blind plate 29 that seals off the lower part of the flame extinguisher 12 and the support part 28.