KR19980067774A - Intake and exhaust system of multi-cylinder internal combustion engine - Google Patents

Abstract

The present invention relates to an intake and exhaust device of a multi-cylinder internal combustion engine. More specifically, a surge tank, a cylinder head provided with each intake port and an exhaust port and provided with an intake valve or an exhaust valve, is installed between the surge tank and the cylinder head or each cylinder intake port to relieve intake air in the surge tank. An intake system having an intake manifold branched to an intake port of each cylinder, and one end connected to an exhaust port of each cylinder, and the other end connected to an exhaust pipe, wherein the exhaust gas discharged from each cylinder is combined. An intake / exhaust system of a multi-cylinder internal combustion engine composed of an exhaust manifold sent to a side, and an exhaust system having a muffler provided in the exhaust pipe, wherein the intake system separates the intake air backflowed with the intake air sucked separately for each cylinder. In communication with each intake branch manifold of the cylinder A plurality of intake condenser tanks installed and a control hose for communicating with each of the intake condenser tanks are provided so that the intake air flowing back from the intake port immediately after the end of the intake stroke of one of the cylinders is returned through the intake branch manifold. Inhaled in the intake condenser tank and partly stored, and the rest is supplied to the intake port of the other cylinder through the control hose to the intake stored in the next intake condenser tank to perform the suction stroke in the next sequence, the exhaust The system includes an exhaust condenser tank installed in communication with the exhaust pipe at a plurality of places in the exhaust pipe to suck and store a portion of the exhaust gas which is rapidly discharged immediately after the exhaust stroke of the cylinder, and discharge the exhaust gas after completion of the exhaust stroke. Continuously without exhaust gas And a bypass pipe connected to each end at both front and rear ends of the muffler, so that a part of the exhaust gas before passing through the muffler passes through the bypass pipe and merges with the exhaust gas passing through the muffler. When the negative pressure is obtained to increase the exhaust gas discharge rate is provided an intake and exhaust device of a multi-cylinder internal combustion engine.

Description

Intake and exhaust system of multi-cylinder internal combustion engine

The present invention relates to an intake and exhaust device of a multi-cylinder internal combustion engine, and more particularly, is mounted on an internal combustion engine used as a power source for construction heavy equipment or automobiles, and supplies air or a mixer to each cylinder, or burns in each cylinder. It relates to an intake and exhaust device of a multi-cylinder internal combustion engine to further improve the intake and exhaust efficiency of the intake and exhaust device for discharging the exhaust gas to the atmosphere.

In general, the operating cycle of an internal combustion engine refers to the periodic change of gas in the cylinder until the air or mixer is sucked into the cylinder to complete the work and become exhaust gas and out of the cylinder.

In the case of gasoline engines, an intake stroke for injecting a mixture of air and fuel from the inlet port of each cylinder, a compression stroke for compressing the inhaled mixture at high temperature and high pressure, and ignited by a compressed mixer are burned. It consists of an expansion stroke that expands and generates power at that pressure, and an exhaust stroke that exhausts the exhaust gas in the cylinder.

Also in the case of diesel engines, the cylinder includes a suction stroke that sucks air into the cylinder, a compression stroke that compresses the sucked air into the combustion chamber to make it hot, and an expansion stroke and exhaust gas that generate power by injecting and burning fuel into the heated air. It consists of an exhaust stroke that discharges out.

On the other hand, the multi-cylinder engine operates in the internal combustion engine constituting the operation cycle as described above, which consists of an intake system for sucking air or a mixer in the cylinder and an exhaust system for exhausting exhaust gas after combustion. have.

1 is a perspective view schematically showing a conventional intake and exhaust device of an internal combustion engine. As shown in FIG. 1, the structure of the intake device includes an air cleaner 1 for filtering inhaled air, and a filter disposed in the air cleaner 1. A throttle body 3 incorporating a throttle valve 2 for controlling the intake air amount, a surge tank 4 through which the air passing through the throttle body 3 temporarily collects, and the air in the surge tank 4 An intake manifold 6 composed of a plurality of intake manifold tubes for uniformly supplying the cylinders 5 to each cylinder 5 is provided.

The exhaust device has an exhaust manifold 7 which synthesizes the gas discharged after combustion in each cylinder 5 and exhaust gas before exhausting the exhaust gas integrated in the exhaust manifold 7 into the atmosphere. The catalytic converter 8 which oxidizes or reduces harmful CO, HC, and NOx to harmless CO 2, H 2 O, and N 2, and the sub and main mufflers 9 and 10 that reduce exhaust noise by lowering the temperature and pressure are exhaust pipes 11. Installed on the

Before describing the intake and exhaust device of a conventional multi-cylinder internal combustion engine configured as described above, the engine shown is a gasoline engine using gasoline as fuel, and the engine is a four-cylinder in-line.

First, the intake apparatus is formed by the negative pressure due to the lowering of the piston in each cylinder and the opening of the suction valve. When the piston descends to the bottom dead center, a vacuum is formed inside the cylinder. As the negative pressure is generated in the intake manifold 6 due to the vacuum force generated at this time, the air filtered through the air cleaner 1 is temporarily collected in the surge tank 4 through the throttle valve 2 and then intake Through the manifold 6 is sucked into the cylinder which constitutes a suction stroke.

Therefore, during the suction stroke in which air is sucked into the cylinder through the intake manifold 6 by the vacuum force generated inside each cylinder, the outside air is sucked into the cylinder with a strong suction force and speed.

However, when the suction valve is completed and the suction valve is closed, the air sucked by the strong suction force is reflected by the collision with the suction valve this time and flows back toward the intake manifold (6). There is a problem that generates a lot of interference and resistance with the air and at the same time generates a large noise, as well as the engine output is lowered.

On the other hand, the gas discharged from each cylinder is formed by the positive pressure between the rise of the piston and the pressurization pressure of the combustion pressure in the cylinder. Therefore, since the residual pressure after combustion in the cylinder is considerably high, the velocity of the exhaust gas flowing into the exhaust manifold 7 in the cylinder at the moment of opening the exhaust valve exceeds the speed of sound and is at a high temperature and high pressure.

Therefore, the exhaust device collects the gas which has been burned in each cylinder by the exhaust manifold 7 and then discharges it to the atmosphere through the exhaust pipe 11, at which time the catalytic converter installed on the exhaust pipe 11. (8) and to the atmosphere through the server and main muffler (9) (10). That is, before the gas discharged from each cylinder is combined by the exhaust manifold 7 and discharged through the exhaust pipe 11 into the atmosphere, the catalytic converter 8 makes the harmful CO, HC, NOx in the exhaust gas harmless. Oxidation or reduction with H2O, N2 to discharge into the atmosphere and at the same time lower the temperature and pressure by the sub and main muffler (9) (10) to reduce the exhaust noise to discharge to the atmosphere.

In particular, the interior of the sub and main muffler (9) (10) is divided into several spaces so that the exhaust gas is gradually noise by causing interference of sound waves passing through their barriers, reducing pressure fluctuations, lowering the exhaust temperature, and the like. have.

In this case, if the resistance of the muffler is too large to increase the noise effect, the engine's sound level decreases, but the resistance to the exhaust stroke, that is, the back pressure is increased, resulting in a decrease in the output of the engine.

Accordingly, an object of the present invention is to intake the intake condensate tank which is flowed back after the intake stroke temporarily to store a part of the intake condenser tank and the remaining intake is stored in the intake condenser tank of the cylinder to perform the next intake stroke through the control tube It is to provide an intake and exhaust device of a multi-cylinder internal combustion engine that can increase the intake efficiency by supercharging the intake air introduced into the cylinder for performing the suction stroke by joining with the intake air sucked from the outside.

Another object of the present invention is to store a portion of the gas discharged during the exhaust stroke in the exhaust condenser tank when the exhaust pressure is reduced after the exhaust stroke is completed to maintain a continuous flow of exhaust gas to improve the exhaust efficiency An intake and exhaust device of a multi-cylinder internal combustion engine can be provided.

1 is a perspective view schematically showing a conventional intake and exhaust device of an internal combustion engine;

2 is a perspective view showing an intake and exhaust device of an internal combustion engine according to an embodiment of the present invention;

3 is an operation of the intake system of the internal combustion engine according to the present invention,

4 is an operation of the exhaust system of the internal combustion engine according to the present invention.

* Explanation of symbols for main parts of the drawings

21: surge tank

22: intake branch manifold

24: intake condenser tank

25: control hose

30: cylinder head

31 ~ 34: cylinder

40: exhaust manifold

41: exhaust pipe

42: catalytic converter

43: sub muffler

44: main muffler

45: bypass tube

50: exhaust condenser tank

51: third condenser tank

The above object of the present invention is a surge tank, a cylinder head having each intake port and an exhaust port and provided with an intake valve or an exhaust valve, and installed between the surge tank and the cylinder head or each cylinder intake port, and the surge tank. An intake system including an intake manifold for branching and supplying intake air to the intake port of each cylinder, and one end connected to an exhaust port of each cylinder and the other end connected to an exhaust pipe, thereby combining exhaust gas discharged from each cylinder In the intake and exhaust device of a multi-cylinder internal combustion engine composed of an exhaust manifold which is sent to the exhaust pipe toward the exhaust pipe, and an exhaust system provided with a muffler provided in the exhaust pipe, the intake system is an intake air that is separately sucked with each intake cylinder To separate and separate each intake branch manifold of each cylinder And a plurality of intake condenser tanks installed to communicate with each other, and a control hose for communicating the intake condenser tanks with each other, thereby allowing the intake branch pipe which is reflected back from the intake port immediately after the end of the intake stroke of one of the cylinders. Inhaled in the intake condenser tank through the part is stored, and the rest is joined to the intake stored in the next intake condenser tank through the control hose to supplement the supply to the intake port of the other cylinder to perform the suction stroke in the next sequence, The exhaust system includes an exhaust condenser tank installed at a plurality of places in the exhaust pipe to communicate with the exhaust pipe, and sucks and stores a part of the exhaust gas rapidly exhausted immediately after the exhaust stroke of the cylinder. To exhaust the exhaust gas without interruption And a bypass pipe connected to each end at both front and rear ends of the muffler, so that a part of the exhaust gas before passing through the muffler passes through the bypass pipe and passes through the muffler. It is achieved by providing an intake and exhaust device of a multi-cylinder internal combustion engine characterized by increasing the exhaust gas discharge rate by obtaining a negative pressure when joined.

According to a preferred feature of the present invention, at least one or more third capacitors are provided in the bypass pipe.

Hereinafter, preferred embodiments of the present invention will be described based on the accompanying drawings.

2 is a perspective view showing an intake and exhaust device of an internal combustion engine according to an embodiment of the present invention, Figure 3 is an operation of the intake system of the internal combustion engine according to the present invention, Figure 4 is an internal combustion engine of the present invention This is the operation diagram in which the exhaust system works.

As shown in the figure, a surge tank 21 through which intake air sucked from the outside is temporarily collected, a cylinder head 30 provided with an intake port and an exhaust port and provided with an intake valve, and the above-described surge tank ( An intake branch manifold 22 which is provided between the cylinder head 30 or the intake ports of the cylinders 31 to 34 to branch supply the intake air in the surge tank 21 to the intake port of each cylinder, and each cylinder. One end is connected to the exhaust port of the 31 to 34 and the other end is connected to the exhaust pipe 41, and the exhaust manifold 40 which combines the exhaust gas discharged from each cylinder 31 to 34 and sends it to the exhaust pipe 41 is provided. And the catalytic converter 42 and the sub and main mufflers 43 and 44 installed in the exhaust pipe 41 described above.

In addition, a plurality of intake condenser tanks are provided to separate the intakes sucked separately from each of the above-described cylinders 31 to 34 and communicate with the intake branch manifolds 22 of each of the cylinders 31 to 34. 24 and a control hose 25 for communicating with the intake condenser tanks 24 with each other.

In addition, the exhaust condenser tank 50 provided to communicate with the exhaust pipe 41 in a plurality of places of the exhaust pipe 41 described above, and the bypass pipe 45 each end connected to the front and rear ends of the main muffler 44 described above. ).

Preferably, at least one or more third condenser tanks 51 are provided in the bypass pipe 45 described above.

Reference numeral 23 denotes a connection hose connecting the intake branch manifold 22 and the intake condenser tank 24.

Hereinafter, the operation of the present embodiment configured as described above will be described.

As shown in FIG. 3, when the engine is started, the intake valve is opened during the intake stroke along the operation cycle of the engine, the piston 31 is lowered in the cylinder 31, and the inside of the cylinder 31 is in a vacuum state, and the intake branch is driven by this vacuum force. The intake air flowing through the air cleaner and the throttle body due to the negative pressure of the manifold 22 passes through the surge tank 21 and is sucked into the cylinder 31 through the intake branch manifold 22 (see arrow A).

On the other hand, when the intake stroke is completed, the intake valve is closed and the intake air, which has been sucked with a strong suction force, flows back out. At this time, the intake air flowing into the intake condenser tank 24 is partially stored and the rest is stored in the control hose 25. Is supplied to the other cylinder 33 which performs the suction stroke in the next sequence (see arrow: B).

At this time, the intake air supplied to the cylinder 33 through the control hose 25 and the new intake air (arrow C) sucked into the surge tank 21 from the outside are joined to each other through the intake branch manifold 22 to perform the intake stroke. It is supplied into the cylinder 33 to perform.

Therefore, a part of the intake air flowing back immediately after the intake stroke by the intake condenser tank 24 is stored, and the rest of the intake stroke is again performed by supercharging the cylinder 33 to perform the next intake release through the control hose 25. In this case, interference due to mutual collision with other intake air supplied to the intake port through the intake branch manifold 22 is eliminated, while the intake air temporarily stored in the intake condenser tank 24 is sequentially controlled through the control hose 25. By supplementing and supplying to the intake port of the other cylinder 33 performing the suction stroke, the new intake according to the suction stroke is supercharged to supply the intake air into the cylinder 33.

As shown in Fig. 4, the combustion gas is rapidly discharged through the open exhaust valve and the exhaust port as the piston in the cylinder rises during the exhaust stroke, that is, after the expansion stroke that generates the power. The exhaust gas is collected by the exhaust manifold 40 and then discharged to the atmosphere via the exhaust pipe 41 through the catalytic converter 42 and the sub and main mufflers 43 and 44 (arrow: see X).

On the other hand, a part of the gas discharged during the exhaust stroke flows into the plurality of exhaust condenser tanks 50 installed in the exhaust pipe 41, and another part of the exhaust gas is connected at both ends before and after the main muffler 44. Some of the exhaust gas passing through the bypass pipe 45 and passing through the bypass pipe 45 flows into and is stored in the third condenser tank 51 provided at the inlet and outlet sides (see arrow: X).

In this way, the exhaust gas stored in the exhaust condenser tank 50 at the time of exhaust stroke is discharged by the pressure difference when the exhaust pressure in the exhaust pipe 41 drops rapidly when the exhaust stroke is completed (see arrow: Y). While maintaining the flow of exhaust gas, a very large high speed gas flow is generated at the connection between the bypass pipe 45 and the exhaust pipe 41, and this high speed gas flow reduces the pressure at the connection due to the venturi effect. As a result, the effect of strongly sucking the exhaust gas passing through the main muffler 44 can be obtained. In addition, by inducing a continuous flow of exhaust gas in the bypass pipe 45 by the pressure difference between the third condenser tank 51 installed in the bypass pipe 45, the remaining exhaust gas remaining in the main muffler 44 can be effectively removed. It can be discharged.

As described above, the intake and exhaust device of the multi-cylinder internal combustion engine according to the present invention is characterized in that the engine output due to the reduction of the intake resistance and the supercharge effect is greatly improved by eliminating the interference of the intake air flowing into the cylinder during the intake stroke. Reduction of harmful gases by combustion and overheating of the engine is prevented, and fuel cost is reduced by improving engine thermal efficiency.

In addition, the interference of the exhaust gas is eliminated, the noise is reduced by reducing the exhaust resistance, and at the same time, the output of the engine is greatly improved by reducing the back pressure.

In addition, the braking distance is shortened due to the improvement of the engine brake performance due to the improvement of the engine output, and the acceleration and deceleration of the engine is sensitive, and the grip between the tire and the road surface is improved. There is a decreasing effect.

Claims (2)

A surge tank, a cylinder head having an intake port and an exhaust port and having an intake valve or an exhaust valve installed therebetween, is provided between the surge tank and the cylinder head or each cylinder intake port to provide intake air in the surge tank. An intake system having an intake manifold for branch supply to a port, and an exhaust manifold having one end connected to an exhaust port of each cylinder and the other end connected to an exhaust pipe and combining exhaust gas discharged from each cylinder to the exhaust pipe In the intake and exhaust device of a multi-cylinder internal combustion engine comprising an exhaust system having a muffler installed in the exhaust pipe: The intake system, A plurality of intake condenser tanks installed to separate the intakes which are separately sucked from each cylinder and the intakes that flow back and communicate with each intake branch manifold of each cylinder; As the control hose communicates with each other of the intake condenser tanks, the intake air reflected from the intake port immediately after the end of the intake stroke of one of the cylinders is sucked into the intake condenser tank through the intake branch manifold. And the rest is supplemented to the intake port of the other cylinder which performs the suction stroke in the next step by joining the intake stored in the next intake condenser tank through the control hose. The exhaust system, As a plurality of exhaust condenser tanks are provided in communication with the exhaust pipes at a plurality of the exhaust pipes, a portion of the exhaust gas which is rapidly discharged immediately after the exhaust stroke of the cylinder is sucked in and stored and discharged after the exhaust stroke is completed to discharge the exhaust gas. To be discharged continuously without interruption, By providing a bypass pipe connected to each end at both ends of the muffler, when the part of the exhaust gas before passing through the muffler passes through the bypass pipe and merges with the exhaust gas passing through the muffler, negative pressure is obtained. Intake and exhaust device of the multi-cylinder internal combustion engine, characterized in that for increasing the exhaust gas discharge rate. The method according to claim 1, At least one or more third condensers are provided in the bypass pipe.