KR820001569B1 - Intake control apparatus - Google Patents

Abstract

Induction control appts. has an exhausts gas recirculation path(8) from the exhaust to inlet manifold(7). Recycling part of the exhaust reduces the peak combustion temperature. Recirculation rate control valves(9,10) are in the recirculation path(8) in series with another control valve. A dilution path(23), which enters the recirculation path between the rate control valve and the other control valve, allows the admission of atmospheric air or lean gas mixture to reduce the mixture strength. An induction control valve(24) is fitted in the dilution path(23).

Description

Intake Control

1 is a cross-sectional view showing a first embodiment of the present invention.

2 is a schematic diagram showing a control device provided in the first embodiment.

3 is an output diagram of an engine illustrating the operation of the first embodiment.

4 is a sectional view showing a modification of the control device according to the first embodiment.

5 is an output diagram of an engine illustrating the operation of the modification.

6 is a cross-sectional view showing another modification of the control device according to the first embodiment.

7 is a schematic diagram showing a second embodiment of the present invention.

8 is a schematic diagram showing a third embodiment of the present invention.

9 is an output diagram of an engine for explaining the operation in the third embodiment.

The present invention relates to an intake control device for adding a part of exhaust gas and air to an intake system of an internal combustion engine according to an operating state.

In general, the exhaust gas reflux device of an internal combustion engine is installed to reduce harmful NOx in the exhaust gas, and reduces the generation of NOx by reducing the combustion temperature by introducing a part of the exhaust gas into the cylinder in the intake system of the internal combustion engine. will be.

However, refluxing the exhaust gas generally results in poor combustion efficiency of the fuel in the cylinder, and when a large amount of the exhaust gas is refluxed, the output is lowered, the fuel consumption is increased, the operability is lowered, and the operation is unreasonable. Occurs.

Therefore, conventionally, a complicated control means suitable for various operating conditions has been devised in consideration of the amount of NOx generated, the output, and the consumption of fuel.

However, as a means of reducing the amount of NOx generated in the combustion process, a lean combustion method is known in addition to the above-described exhaust gas refilling method. The lean-mixed gas is more poorly flammable and less flammable, and various methods have been adopted as a countermeasure.

For example, there may be a stale combustion method, a laminar combustion method, or a vortex generation method. In such a method, a rich mixed gas is introduced into or near the spark plug. Is strongly scavenged to improve the ignition and at the same time to generate a strong vortex to improve the flame propagation speed has been improved.

There are two ways to reduce the amount of NOx generated above. There is one end, and the reduction rate of NOx is high in the reflux method of exhaust gas, but it is inferior in the output and consumption of fuel. Although it is difficult to control the mixing ratio of the fuel and the reduction rate of NOx is lowered, there is an advantage that the fuel consumption is improved and the operability is good as compared with the reflux method of the exhaust gas.

The main object of the present invention is to provide intake control to reduce the amount of NOx generated by adding a part of the exhaust gas of the intake cylinder and air or lean mixed gas according to the operating state.

It is another object of the present invention to provide an intake control apparatus for an automobile engine which minimizes the decrease in output, the consumption of fuel, and the deterioration of driving performance to minimize the amount of NOx generated. In order to provide an intake control device with a simple structure, the control of the supply amount of air or lean mixed gas to be introduced is combined with a specific control valve in the exhaust gas reflux device.

It is also an object of the present invention to smoothly switch between the reflux of the exhaust gas and the dilution of the air or the lean mixed gas, without any overlap between the two or the operation stop period. It provides an intake control device for an engine of a vehicle in which the driving performance is improved at the same time and the NOx emission is reduced. Another object is to provide a low speed or low load when driving a large area in a city area, for example. While reducing the amount of emissions generated by refluxing the exhaust gas during operation, and reducing the reflux of the exhaust gas during high speed or high load operation, diluting the mixed gas by introducing air or a lean mixed gas into the intake cylinder. SUMMARY OF THE INVENTION An object of the present invention is to provide an intake control apparatus for automobiles that improves driving performance and fuel consumption and suppresses the occurrence of knocking.

All the above-mentioned objects have a reflux passage for communicating a part of the exhaust gas to the intake passage by communicating the exhaust passage with the intake passage, and at least two control valves for controlling the reflux amount of the exhaust gas in the exhaust gas reflux passage in series. And a dilution suction passage for sucking air or lean mixed gas by forming an exhaust gas return passage between two specified control valves among the plurality of control valves, and an intake control valve intervening in the dilution suction passage. It is achieved by the intake control device characterized in that.

Next, the present invention will be described in detail with reference to the embodiments shown in FIGS. 1 to 9 as follows. In addition, in each Example, the same code | symbol is attached | subjected to the same or equivalent member and part.

In the first embodiment of the present invention shown in FIGS. 1 to 3, the throttle valve 3 interlocked with an accelerator pedal not shown in the middle of the intake passage 2 of the vaporizer 1 has a shaft 4 A position upstream of the throttle valve 3 slightly upstream from the totally closed position of the throttle valve 3 opposite to the upstream free end 5 of the throttle valve 3. The pot 6 is installed in the pot 6, and the pot 6 is opened at a lower angle to the predetermined position, for example, about 15 degrees to 20 degrees or more. It is downstream from the free end 5 of 3).

Two exhaust gas reflux for opening and closing the passage communicated with the exhaust passage (not shown) to the intake manifold 7 for distributing and supplying the mixed gas to each cylinder of the multi-cylinder engine connected to the vaporizer 1 described above. Quantity control valves 9 and 10 are provided in series.

Next, the control valve 9 located upstream of the exhaust gas return passage 8 will be described. A valve body 9 'whose tip is closed in contact with the valve seat 11 provided in the passage 8 will be described. The rear end is installed at the center of the diaphragm 12, while the diaphragm 12 divides the housing 13 into two chambers so that one chamber 14 is opened through the hole 14 'and the other chamber 15 communicates with the above-mentioned through hole 6 through the load passage 16, and the spring 15 is built into the chamber 15 so that the pressure causes the diaphragm 12 to close in the control valve 9 direction. Push

Next, the control valve 10 located downstream from the control valve 9 will be described. The valve body 10 'which is closed by contacting the tip of the valve seat 18 provided in the exhaust gas return passage 8 will be closed. At the rear end of the link 19, the other end of the link 19 is connected to the free end of the lever 20 fixed to the throttle shaft 4 so that the spring 21 is elastic in the direction in which the valve body 10 'is sealed. Between the control valves 9 and 10 of the exhaust gas return passage 8, a dilution suction passage 23 through which the air is sucked through the air filter 22 passes. An intake control valve 24 is provided in the passageway 23.

In addition, when the intake control valve 24 described above is described, the rear end portion of the valve body 24 ′, which is closed while the front end contacts the valve seat 25 provided in the dilution suction passage 23, is formed of the diaphragm 26. The case 27 of the diaphragm 26 divides it into two chambers so that one side chamber 28 is opened to the air through the hole 29 and the other chamber 30 is in communication with the negative pressure passage 16. The negative pressure passage 31 communicates with the spring 32 in the vacancy 30 to push the diaphragm 26 in the direction in which the control valve 24 is closed.

The orifices 33 and 34 are provided in the negative pressure passages 16 and 31, respectively, and the orifices 33 and the empty spaces 15 and the orifices 34 and the empty pressure passages 31 of the negative pressure passages 31 are respectively provided. The passages 35 and 36 communicate with each other between the 30, and both passages 35 and 36 are connected to the control device 37. The control device 37 selectively opens and closes both passages 35 and 36 by the solenoid valve 38 as shown in FIG. 2, and when the one side passage is closed, the other passage is opened and the air filter 40 The hole 39 in which is installed was opened in communication with the atmosphere.

In the embodiment of the present invention, the engine speed is set by the vehicle speed sensor 41, for example, the passage 35 is opened by closing the passage 35 with the spring 38 'at 3000 rpm or lower, and the passage 36 is opened. The solenoid 40 'acts to open the passage 35 while closing the other passage 36.

Next, the creation of the first embodiment described above will be described with reference to FIG. 3, and FIG. 3 is an output line diagram of the engine in which the output PS of the engine is indicated on the vertical axis and the engine speed (rpm) on the horizontal axis. J) is the output line when the throttle valve 3 is fully open, the solid line K is the idle line [3 degrees-6 degrees], and the output line and the solid line L are the pots 6 ) Negative pressure line (hereinafter referred to as EGR boost) of 100mmHg and solid line (M) are lines of constant rotation speed when the engine speed becomes 3000rpm.

When the engine is driven and opened more than necessary as described by the throttle valve 3, the EGR boost is generated in the port 6, and the negative pressure is introduced into the vacancy 15 through the negative pressure passage 16, thereby providing a negative pressure passage. It is introduced into the vacancy 30 through (16) (31).

However, when the engine speed is less than 3000rpm, the vehicle speed sensor 41 does not generate an output and the solenoid valve 38 closes the passage 35 by the spring 38 'and the passage 36 opens to the atmosphere. Therefore, the atmosphere is supplied into the vacancy 30 through the passage 36 and the negative pressure passage 31. In this case, in the negative pressure passage 31, the atmosphere does not affect the negative pressure generated in the vacancy 15 by the orifice 34, and the vacancy 15 is the same as the EGR boost generated near the port 6. Negative pressure is generated.

Therefore, when the engine output and rotational speed change and the EGR boost becomes a set value, for example, 100 mmHg or more, the control valve 9 closed by the elasticity of the spring 17 is sucked by the diaphragm 12 by the EGR boost. The valve body 9 'is then opened against the spring 17, which opens in response to the magnitude of the EGR boost, thereby changing its position.

In FIG. 3, the solid line L is an isobar pressure line when the boost is 1000 mmHg when the control valve 9 starts to open, and the control valve 9 is in the region A in which the engine speed is 3000 rpm or less to the right of the solid line L. ) Is opened and its opening and closing is determined according to the size of the EGR boost.

On the other hand, when the engine speed is 3000rpm or more, the solenoid valve 38 operates according to the instruction of the vehicle speed sensor 41, so that the passage 35 is opened to the atmosphere and the passage 36 is closed, thereby blocking the supply of air. The atmosphere is supplied to the vacancy 15 through the passage 35 and the negative pressure passage 16.

In such a case, the supply of air by the negative pressure passage 16 has no particular effect on the negative pressure generated in the vacancy 30 by the orifice 33 and is generated near the port 6 in the vacancy 30. The same negative pressure occurs as the EGR boost.

Like the control valve 9 described above, the control valve 24 is also set to open by the spring 32 when the operating negative pressure of the diaphragm 26 is 1000 mmHg or more. On the right side, the control valve 24 is opened in the area B of the engine speed of 3000 rpm or more, and air is supplied from the dilution suction passage 23 to the exhaust gas return passage 8.

On the other hand, the control valve 10 is opened in conjunction with the link 19 in accordance with the opening degree of the throttle valve (3) and the opening degree is proportional to the opening and closing degree of the throttle valve (3).

Therefore, the exhaust gas is returned to the intake manifold 7 through the reflux passage 8 according to the pressure difference between the pressure of the exhaust gas and the negative pressure of the intake manifold, so that if the passage resistance of the passage 8 is the same In the operating state in which the throttle valve 3 has a small opening degree and a high negative pressure of the intake manifold, the reflux amount of the exhaust gas increases, but the reflux amount of the exhaust gas becomes excessive in the low load region, and in the medium or high load region, The inconvenience that the reflux amount of the exhaust gas is too small is solved according to the characteristic of the opening degree of reducing the amount of throttle in inverse proportion to the output of the engine by the control valve 10.

In the present embodiment, the control valves 9 and 10 are opened in the area A, which is particularly combustible and tends to generate a large amount of NOx, and is closed by the intake control valve 24 in the driving area that is frequently used when driving in the city area. As a result, a part of the exhaust gas is sucked into the intake manifold 7 through the exhaust gas reflux passage 8 and mixed into the mixed gas generated in the vaporizer 1.

The reflux amount of the exhaust gas is controlled in accordance with the opening degree of the above-described control valves 9 and 10, and an appropriate amount of exhaust gas suppresses NOx generated in the driving state of the engine in which the exhaust gas is not refluxed in response to the generated amount. The reflux amount of is controlled to be controlled.

In addition, the control valve 9 is closed and the control valve 10 and the intake control valve 24 are opened to open the air filter, especially in the area B, which is frequently used when driving outside the city, where the amount of NOx is likely to be high. The air purified from (22) is sucked into the intake manifold 7 through the dilution suction passage 23 and the exhaust gas reflux passage 8 to dilute the mixed gas produced in the vaporizer 1.

In addition, the above air intake amount is related to the opening degree of the control valve 10 and the intake control valve 24. If the mixing of the air is not performed, a large amount of air is sucked and mixed in the operating region where a large amount of NOx is likely to occur. Diluting the gas effectively inhibits the generation of NOx.

In the above embodiment, when the operating state moves from the area (A) to the area (B) or from the area (B) to the area (A), the atmosphere is smoothly sucked from the reflux of the exhaust gas or is sucked into the atmosphere. Is switched to the reflux of the exhaust gas, and during the switching, the output does not change temporarily temporarily and the operability is good.

As described above, according to the present embodiment, air is not introduced into the exhaust passage for reflux and dilution of the exhaust gas in the vicinity of the development and idle for output, resulting in a decrease in output and deterioration of fuel consumption. Unfavorable conditions such as vibration of the engine are prevented, and NOx is effectively reduced by the reflux of the exhaust gas whose reflux amount is controlled by the control valves 9 and 10 in the low speed region, and in the high speed region, the NOx is effectively reduced. It is controlled by the intake control valve 24, and the suitable gas is inputted so that the mixed gas is diluted, thereby reducing the amount of NOx generated, improving fuel consumption, and suppressing knocking due to premature ignition.

Next, a modified example of the control device 37 according to the first embodiment described above is shown in FIG. 4 and FIG. 4 by the control device 37 shown in FIG. 4, which includes two diaphragm devices 42 and 43. And an opening / closing valve 45 interlocked with the diaphragm 44 of the diaphragm 42 controls the atmospheric opening passage 35 in the first embodiment and the diaphragm of the diaphragm apparatus 43. The on-off valve 47 interlocked with 46 controls the opening passage 36 of the first embodiment. In addition, in the negative pressure chamber 48 acting on the diaphragm 44, the negative pressure passage 50 through which the orifice 49 is interposed causes the intake of air generated at a predetermined point in the intake passage 2 shown in the first embodiment. The negative pressure chamber 52 acting on the diaphragm 46 while sucking the diaphragm 44 in the direction in which the on-off valve 45 opens against the force of the spring 51 reloaded under negative pressure and loaded into the negative pressure chamber 48. Is connected to the passage 35 through the negative pressure passage 53 and the same negative pressure generated in the negative pressure chamber 15 in the first embodiment is generated in the negative pressure chamber 52 and the negative pressure chamber 52. The diaphragm 46 is sucked in the direction in which the opening / closing valve 47 opens against the resilience force of the spring 54 inserted into the valve.

In the above-described modification, the negative pressure passage 50 is connected to the port 6 '(shown in FIG. 1) installed in the intake pipe wall slightly upstream from the port 6 in the first embodiment. In the case of connection, control as shown in the output diagram of FIG. 5 is performed. The same reference numerals are given to the same or equivalent parts as those in FIG. 3 in the output diagrams of FIGS. 5 and 9 below.

In FIG. 5, the solid line M is a negative pressure of the pot 6 ′ in which the eastern pressure line is generated in the high negative pressure chamber 48 when the negative pressure set in the negative pressure chamber 48 is actuated to open and close the valve 45. When the pressure is lower than the set pressure, the on / off valve 45 is closed by the spring force of the spring 51, and the negative pressure generated in the pot 6 'is conducted to the negative pressure chamber 15 through the negative pressure passage 16. It is also connected to the negative pressure chamber 52 through the passages 35 and 53 so that the on-off valve 47 is opened by the negative pressure while the passage 36 is open to the atmosphere.

On the other hand, when the negative pressure generated in the negative pressure chamber 48 is higher than the set pressure, the on-off valve 45 is opened and the passage 35 is opened to the atmosphere so that the negative pressure chamber 52 is at atmospheric pressure and the on / off valve is operated by the force of the spring 46. 47 is closed. Accordingly, in FIG. 5, the solid line L is refluxed from the exhaust gas in the right side and the left region C of the solid line M, and the dilution air is introduced in the right region D of the solid line M. In the other operating region, the reflux of the exhaust gas and the input of air are stopped together.

FIG. 6 shows another variation of the control device 37 in the first embodiment, in which the control device achieves a control equivalent to the control device 37 shown in FIG. 4 in a simplified configuration. A passage (35) (36) and a negative pressure passage (50) are connected to the case (59) having a built-in (56) and divided into two chambers (57, 58), and the negative pressure passage (36) is an open / close valve (60). And the vacancy (63), which is in communication with the vacancy (61) communicating with the vacancy (58) open to the atmosphere, and separated by the vacancy (57) and the bellows (62) in the central portion of the diaphragm (56). A pipe 64 communicating with the vacancy 58 is attached in line with the diaphragm 56 in the axial direction, and the opening end of the vacancy 58 side of the pipe 64 is pipe 64 in FIG. When the position is changed upward, the soup for contacting the on-off valve (60) described above and displaced upward again to pressurize the on / off valve (60) downward. To the on-off valve 60 to open Available 58 61 against the 65 are in communication with each other.

In addition, when the pipe 64 is in contact with the on-off valve 60, communication of the chambers 58 and 63 is blocked, and the passage 35 communicates with the chamber 63 and communicates with the negative pressure passage 50 and the chamber 57. The vacant chamber 57 has a spring 66 for pressing the diaphragm 56 upwards, and an orifice in place of the orifice 49 in the middle of the negative pressure passage 50 connected to the port 6 '. 67 and a check valve 68 are provided in which the flow restrictor 69 is arranged in parallel.

As described above, the control device 37 shown in FIG. 6 and the control device 37 in FIG. 4 obtain almost the same controllability as the control characteristic shown in FIG.

The second embodiment of the present invention shown in FIG. 7 replaces the port 6 in place of the control valve 10 which mechanically interlocks the throttle valve 3 via the link 19 in the first embodiment. Control valve 71 that is controlled pneumatically in response to the magnitude of the negative pressure generated in the port 6 'installed on the intake pipe wall slightly upstream of ) And the bypass passage 72 in parallel with the passage opened by the control valve 71. The control valve 71 has a valve body 73 in the center of the diaphragm 74. Is connected to the port 6 'through the negative pressure passage 76, and the diaphragm in the direction in which the valve body 73 is closed in the negative pressure chamber 75 is connected to the negative pressure chamber 75 to operate the diaphragm 74. It had a structure which incorporates the spring 77 which presses 74. As shown in FIG.

In the above-described second embodiment, the control valve 71 has the same opening degree of the throttle as the control valve 10 of the first embodiment, when the load is light, the excess gas is injected into the reflux gas or the dilution suction passage 23. When the load is high, a large amount of exhaust gas refluxs or injects air at a high load, and there is little underpressure generated in the pot 6 'at low load. Therefore, the negative pressure generated in the negative pressure chamber 75 is also small, and the valve body 73 is closed by the pressure of the spring 71. In such a state, the exhaust gas is refluxed or the air is supplied only through the bypass passage 72. And the distribution is small. On the other hand, under high load, the negative pressure generated in the pot 6 'is large and the diaphragm 74 is sucked against the pressure of the spring 77 according to the high negative pressure generated in the negative pressure chamber 75 so that the valve body 73 In this state, the flow rate is increased because it flows through the valve 71 and the bypass passage 72 with the reflux exhaust gas or the introduced air. The operating states of the control valve 9 and the intake control valve 24 for controlling the amount of reflux of the exhaust gas are the same as in the first embodiment described above.

In the third embodiment of the present invention shown in FIGS. 8 and 9, the control valve 78 is provided in parallel with the control valve 9 installed in the reflux passage 8 of the exhaust gas in the first embodiment. In one configuration, the control valve 78 'is connected to the central portion of the diaphragm 79, and the negative pressure chamber 80 for operating the diaphragm 79 is slightly upstream than the port 6 through the negative pressure passage 76. It communicates with the pot 6 'installed in the wall of the intake pipe on the side, and the negative pressure chamber 80 has a structure in which a spring 81 is applied to apply pressure in the direction of closing the valve body 78'.

The negative pressure passage 76 is provided with an orifice 82, and the negative pressure passage between the orifice 82 and the negative pressure chamber 80 contacts the control device 37 through the branched passage 83 and the branch passage 83. Is opened or blocked to the atmosphere as the passage 35 in the first embodiment.

The operation of the third embodiment will be described with reference to FIG. 9. In FIG. 9, the solid line N is the eastern pressure line when the negative pressure set in the negative pressure chamber 80 acts to open the control valve 78. In the right region of the solid line N, the negative pressure generated in the pot 6 'becomes high negative pressure, and the high negative pressure is introduced into the negative pressure chamber 80 through the negative pressure passage 76 and against the pressure of the spring 81. The diaphragm 79 is aspirated to open the valve body 78 '. In the left region of the solid line N, the negative pressure generated from the port 6' becomes a negative pressure, and the valve body 78 ' Closed by pressure.

Therefore, the control valves 9, 24, and 78 are closed in the operation region on the left side of the solid line L in FIG. 9 so that both the reflux of the exhaust gas and the air input are stopped, and the right and solid lines in the solid line L are stopped. On the left side of (N) and on the left region F of the solid line M, the control valves 9 and 10 are opened, and the return of the controlled gas is performed in response to the opening and closing degrees of both sides 9 and 10. In the region G on the right side in the solid line N and on the left side in the solid line M, the control valves 9, 10, and 78 are opened so that the reflux of the exhaust gas controlled in accordance with the opening and closing degree of these three valves is In the region H on the right side in the solid lines N and M, the control valves 10 and 24 are opened so that the other valves 9 and 78 are closed and the control valves 10 and 24 described above. Controlled air input is performed in response to the system

Therefore, in each of the above-described embodiments, the dilution suction passage 23 communicates with the atmosphere through the air filter 22, and air is introduced into the reflux passage 8 of the exhaust gas from the passage 23, but the passage ( When the 23 is connected to the intake passage 2 between the throttle valve 3 and the venturi of the vaporizer 1, a lean mixed gas is introduced to have the same action and effect as described above.

Claims (1)

An exhaust gas reflux passage communicating the exhaust passage with the intake passage and returning a part of the exhaust gas to the intake passage, at least two exhaust gas reflux control valves installed in series in the exhaust gas reflux passage; An intake control device having an intake control valve provided in a dilution intake passage for forming an exhaust gas reflux passage between the control valves to suck in the atmosphere or lean mixed gas.

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