KR20010060602A - Back fire damping device for LPG engine - Google Patents

Abstract

PURPOSE: A backfire reducing device of an LPG(Liquefied Petroleum Gas) engine is provided to reduce pressure due to backfires without problems in the intake efficiency of an LPG engine by adopting a reducing device opened by external force between an air cleaner and a mixer of an intake system of the LPG engine. CONSTITUTION: In the occurrence of backfires in a low-speed high-load area, the pressure thereof flows along a free straight passage to be applied to a housing(10). A door(12) of the housing is turned out by the pressure regardless of the force of a return spring(13). Thereby, the pressure is discharged to the outside easily. When the pressure is removed by external force, the door is closed again by the return spring without any influence of an intake air flow rate. Air is discharged together with the pressure temporarily. Combustion gas does not rise up to an air intake hose(110) even though backfires are generated actually. The pressure is not transferred to an intake system of an engine. Therefore, the damage of alignment including an air cleaner(100) is excluded as well as the trouble of suction is removed.

Description

Back fire damping device for LPG engine

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backfire damping device of an Elpgi engine. In particular, an intake tube of an Elpgi engine is provided by attenuating a backfire generated due to excessive ignition advancement in a low speed high load region to minimize pressure waves formed by the backfire. It is related to the backfire damping device of the Elpigi engine, which prevents damage to each component constituting the engine and suppresses intake disorders as much as possible, thereby ultimately improving the overall NVH characteristics of the engine and improving the ride comfort of the vehicle.

In general, Elpig, which is used as the fuel of the Elpji engine, is supplied with gas in the mixer of each cylinder, and the exhaust gas contains less carbon monoxide, and the combustion rate is slower than gasoline, relatively higher octane number, and less knocking. In particular, since it is cheaper and more economical than gasoline fuel, it is a trend that a lot of vehicles using Elpji fuel have been preferred in recent years.

In such an Elphi engine, when the engine is driven at a low speed and high load, the intake valve opens longer, and thus, there is a disadvantage in that a backfire phenomenon in which the exhaust gas of the combustion chamber is discharged to the intake side is ignited at a much faster time than the completion of the compression stroke.

This backfire phenomenon is accompanied by a pressure wave, and the pressure wave acts on the intake cylinder to damage each component constituting the intake cylinder, and also causes an intake obstacle, thereby reducing the intake efficiency of the engine. In particular, it is urgent to prepare countermeasures due to the problem that the overall characteristics of the NVH and the vehicle's ride comfort are reduced.

That is, Figure 3 attached schematically shows an intake cylinder of the LLP engine.

Here, the state in which the pressure wave acts is shown as a solid line, and in particular, the air cleaner 100 is easily damaged due to the pressure wave, and the air intake efficiency shown in dotted lines is hindered to reduce the intake efficiency. have.

Reference numeral 110 denotes an air intake hose, and 120 and 130 denote a mixer and an engine body, respectively.

Accordingly, the present invention has been made in view of the above, and is installed by the external force between the air cleaner and the mixer in the intake tube of the LPI engine, which is generated by the backfire phenomenon by opening and closing the self-resilient damping device. By allowing the pressure wave to be attenuated in such a way that it can be discharged to the outside, it is possible to effectively attenuate the pressure wave due to the backfire phenomenon without affecting the inspiratory efficiency of the LLP engine at all. To prevent the intake of air, and to eliminate the risk of intake impairment, and ultimately to improve the overall NVH characteristics of the engine and improve the ride comfort of the vehicle. There is a purpose.

1 is a schematic view showing the installation position of the backfire damping device according to the present invention

FIG. 2 is a perspective view showing the structure of the back feature damping device in FIG.

3 is a schematic view showing an intake cylinder of a typical LLP engine

<Explanation of symbols for main parts of drawing>

10 housing 11 hinge portion

12 door 13 return spring

100: air cleaner 110: air intake hose

120: mixer 130: engine body

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

According to the present invention, in an LLP engine including the air cleaner 100 and the mixer 120, the pressure wave can be discharged while being opened outward by the pressure wave between the air cleaner 100 and the mixer 120. When the wave is extinguished, it is characterized in that the backfire damping device of the opening and closing structure that can be closed inward by the self-resilience.

In particular, the bag fire attenuator is connected to the air intake hose 110 between the air cleaner 100 and the mixer 120, the opposite side of the cylindrical housing 10 and the outside, and the inside of the housing 10 Is disposed vertically inward and is connected to the disc-shaped door 12 that can be folded out or built up around the lower hinge portion 11, the inner wall of the housing 10 and the lower end of the door 12, respectively It is characterized by consisting of a return spring 13 that always maintains the upright state of the door 12.

In addition, the installation angle of the housing 10 is in a straight line with respect to the air intake hose 110 extending from the mixer 120 side, and with respect to the air intake hose 110 extending from the air cleaner 100 side. It is characterized by maintaining at least 45 ° or more.

This will be described in more detail as follows.

1 shows schematically the installation position of the backfire damping device according to the present invention.

The bag fire damping device of the present invention is installed on the air intake hose 110 connected between the air cleaner 100 and the mixer 120 in the intake tube of the LLP engine.

That is, the air intake hose 140 connected between the air cleaner 100 and the mixer 120 is connected in a gentle curve shape while maintaining an angle of 90 °, and extends horizontally from the mixer 120 side. The housing 10 constituting the main body of the backfire damping device is connected to be installed in a structure approximately branched from the end.

At this time, the housing 10 is placed in a straight line with the mixer 120 side and at the same time maintains a predetermined angle with the air cleaner 100 side, that is, an angle of at least 45 ° or more, and thus the mixer 120 side. Pressure waves transmitted from the air can flow into the housing 10 directly without going to the air cleaner 100 side.

2 shows the structure of the backfire attenuation apparatus according to the present invention.

The housing 10 constituting the main body of the bag fire damping device has a substantially cylindrical shape, and has a disc-shaped door 12 which can be folded outwardly or erected inward about the lower hinge portion 11 inside the inner part thereof. ) Is installed.

The door 12 can be erected at all times by at least two return springs 13 on both sides, and can no longer be flipped inward while being erected by a predetermined jaw inside the housing 10. .

Therefore, the operational effects of the backfire damping device according to the present invention configured as described above are as follows.

When the backfire occurs due to excessive ignition advancement in the low speed and high load region, the pressure wave at this time is applied to the housing 10 side while the flow proceeds along a free straight line, and the housing 10 is applied by the force applied by the pressure wave. The door 12 in the) is flipped outward while winning the force of the return spring 13, so that the pressure wave can be easily discharged to the outside.

When it is removed by the external force by the pressure wave, the door 12 is returned to its original closed state by the return spring 13, so that the amount and flow of the intake air are not affected at all.

Here, when the pressure wave is discharged to the outside, the air escaping together is extremely temporary, and even if a backfire occurs, the combustion gas from the combustion chamber does not rise to the air intake hose, so there is no concern about the emission of the combustion gas into the air. You don't have to.

In this way, by blocking the pressure wave generated by the backfire generated in the engine body from being transmitted to the intake cylinder, it is possible to eliminate intake obstacles and to eliminate the concern about damage to the elements of the air cleaner. Accordingly, the body of the air cleaner, which was made of metal such as steel or aluminum to prepare for pressure waves, can be made of plastic, so that weight reduction and cost reduction can be expected.

As described above, the present invention provides a backfire damping device that can effectively attenuate the pressure wave caused by the backfire generated in the LPI engine, thereby improving the performance of the engine by increasing the intake efficiency due to the removal of the pressure wave causing intake failure. It can help to reduce the weight of the air cleaner by replacing the air cleaner with a plastic material, and ultimately improve the overall NVH characteristics of the engine and improve the ride comfort of the vehicle. There is an advantage.

Claims (3)

In the LLP engine including the air cleaner 100, the mixer 120 and the like, Between the air cleaner 100 and the mixer 120 is opened to the outside by the pressure wave to discharge the pressure wave, and when the pressure wave is extinguished back fire damping device of the opening and closing structure that can be closed inward by the self restoring force Backfire attenuator of the Elpji engine, characterized in that installed. The method of claim 1, wherein the bag fire damping device is connected to the air intake hose 110 between the air cleaner 100 and the mixer 120, the opposite side of the cylindrical housing 10 and the outside and the housing ( 10) a disc-shaped door 12 vertically disposed inside the inside of the lower hinge part 11 and being able to be leaned outwardly or standing upright, an inner wall of the housing 10 and a lower end of the door 12 Backfire attenuator of the LPG engine, characterized in that it is composed of a return spring (13) which is connected to each of the above to always maintain the upright state of the door (12). The air intake hose of claim 2, wherein the installation angle of the housing 10 is in a straight line with respect to the air intake hose 110 extending from the mixer 120, and the air intake hose extending from the air cleaner 100. 110. The backfire damping device of the Elpji engine, characterized by maintaining at least 45 ° relative to.