JPS6242113Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an intake device for an internal combustion engine equipped with a supercharger such as an exhaust turbocharger or mechanical supercharger in the intake system of the engine, which is provided with an air cleaner and a surge tank for eliminating pulsation in the intake system, and which connects a secondary air supply passage to the exhaust system to purify the exhaust gas.

Modern internal combustion engines are equipped with superchargers such as exhaust turbo superchargers to improve output and reduce fuel consumption, but the supercharged air compressed by the supercharger is Since there is high-frequency pulsation that occurs during compression in the feeder, guiding this to the engine through the carburetor downstream will adversely affect the fuel supply in the carburetor, and the intake air-fuel mixture will be affected. The air-fuel ratio fluctuates, and high-frequency pulsations and pulsations caused by the opening and closing of the engine's intake valve resonate in a specific rotation range, resulting in a reduction in engine filling efficiency.

Therefore, Japanese Utility Model Application Publication No. 50-27214 as a prior art proposes to provide a surge tank for eliminating pulsation between the carburetor and the supercharger upstream thereof, and to purify the intake air in this surge tank. However, since the atmospheric air containing dust and dirt passes through the turbocharger as it is, this reduces the durability of the turbocharger due to dust and dirt. This is not a good idea as it will cause a significant drop in air pressure, and an air cleaner is required on the suction side of the supercharger.Furthermore, since the surge tank in the prior art is exposed to the atmosphere, the pulsation that occurs in the surge tank may be eliminated. The noise would be transmitted directly to the atmosphere.

In addition, in recent internal combustion engines, secondary air is supplied to the exhaust system using the pulsation of the exhaust gas for the purpose of purifying the exhaust gas. The air supply device is
Noise is generated when the check valve in the secondary air supply passage opens and closes in response to the pulsation of the exhaust gas, and furthermore, when the exhaust gas flows backward through the secondary air supply passage with the check valve. This backflow of exhaust gas could cause a fire in the intake system.

The present invention provides an air cleaner on the suction side of the supercharger and a surge tank on the discharge side of the supercharger. In view of the fact that configuring the air cleaner and surge tank separately when connecting the air supply passages increases the installation space and weight,
By providing the surge tank in the cleaner case of the air cleaner, the installation space and weight can be reduced, and the noise generated when eliminating pulsation in the surge tank is reduced from being transmitted to the atmosphere. This utilizes the presence of the secondary air to reduce noise associated with the supply of secondary air and improves safety against backflow of exhaust gas.

The present invention will be explained below with reference to the drawings of the embodiments. In the drawings, 1 indicates an intake manifold 2 on one side.
4 is an exhaust turbo supercharger directly connected to an exhaust turbine 5 and a blower compressor 6, and 7 is a carburetor with a throttle valve 8 attached to the intake manifold 2. The exhaust manifold 3 is an exhaust passage 9.
An exhaust pipe 10 is connected to the inlet side of the exhaust turbine 5 through the exhaust turbine 5, and an exhaust pipe 10 is connected to the outlet side of the exhaust turbine 5 for discharging exhaust gas to the atmosphere.

Reference numeral 11 indicates an air cleaner attached to the upper surface of the carburetor 7, and the air cleaner 11 is shown in FIGS.
As shown in the figure, there is a cylindrical cleaner case 12 with a bottom plate 13 that is open at the top, a lid 14 that can be opened and closed to close the upper opening of the cleaner case 12, and a plurality of bolts 16 attached to the lower surface of the cleaner case 12. A ring-shaped filter element 17 is disposed inside the cleaner case 12, and a gasket 18 on the upper surface thereof is on the lower surface of the lid body 14, and a gasket 19 on the lower surface is on the upper surface of the bottom plate 13. The inside of the filter element 17 is inserted into the annular dust side chamber 21 which communicates with the atmospheric air intake pipe 20 integrally formed on the outer peripheral surface of the cleaner case 12. The interior of the chamber cover 15 is divided into an intake chamber 23 and a secondary air chamber 24 in a plan view.
A through hole 2 is defined by partition walls 25 and 26, and an intake chamber 23 and a secondary air chamber 24 are formed in the bottom plate 13.
7 and 28 to the clean side chamber 22, and one intake chamber 23 is connected to the cleaner case 12.
A passage 3 is provided in an outlet pipe 29 integrally formed on the outer peripheral surface of the
0 to connect the outlet pipe 29 to the suction side of the blower compressor 6 via a passage 31;
The other secondary air chamber 24 is communicated via a passage 33 with a secondary air outlet pipe 32 integrally formed on the outer peripheral surface of the cleaner case 12.
is connected to the exhaust manifold 3 via a secondary air supply passage 35 with a check valve 34.

Further, in the clean side chamber 22, a cylindrical partition plate 36 with an open top is provided integrally with the bottom plate 13, and a lid plate 37 is provided on the top surface of the partition plate 36.
By fastening with multiple bolts 38,
The inside of the partition plate 36 is connected to the clean side chamber 22.
and a surge tank chamber 39 that does not communicate with the intake chamber 23 or the secondary air chamber 24, and communicates the surge tank chamber 39 with an inlet pipe 40 integrally formed on the outer peripheral surface of the cleaner case 12 via a passage 41. A supercharging passage 42 from the discharge side of the blower compressor 6 is connected to the inlet pipe 40, while an outlet pipe 43 communicating with the surge tank chamber 39 is integrally connected to the lower surface of the chamber cover 15. The outlet pipe 43 is connected to the inlet pipe part 4 of the vaporizer 7.
A through hole 27 for communicating the intake chamber 23 with the clean side chamber 22 is disposed near the atmospheric air intake pipe 20, while connecting the secondary air chamber 23 to the clean side chamber 22. A through hole 28 for communicating with the chamber 22 is provided at a location opposite to the through hole 27 in the intake chamber 23 with the surge tank chamber 39 interposed therebetween.

The air cleaner 11 has two bolts 45 erected from the top surface of the inlet pipe section 44 of the carburetor 7.
a nut 46 protruding from the upper surface of the lid plate 37 of the surge tank chamber 39 and screwed onto the upper end of the bolt 45.
By fastening the inlet pipe part 4 of the carburetor 7
4, and the air cleaner 11
The lid body 14 is the lid plate 3 of the surge tank chamber 39.
7 with a bolt 47. Further, on the lower surface of the chamber cover 15, a blow-by gas inlet pipe 4 for guiding blow-by gas from the engine 1 to the intake chamber 23 via a passage 48 is provided.
9 is provided. Furthermore, 50 is configured to release a portion of the supercharged air from the surge tank chamber 39 to the secondary air chamber 24 through the through hole 51 when the supercharging pressure downstream of the blower compressor 6 exceeds a certain value. A blow-off valve is shown.

In this configuration, atmospheric air that flows from the air intake pipe into the dust side chamber 21 of the cleaner case 12 as the engine 1 is operating is filtered and purified by the filter element 17, and then flows from the clean side chamber 22 into the through hole 27. The air enters the blower compressor 6 of the exhaust turbo supercharger 4 through the intake chamber 23 and is compressed, causing dust and dirt in the atmosphere to enter the blower compressor 6 and reduce the durability of its impeller, bearings, etc. Then, the supercharged air compressed by the blower compressor 6 enters the surge tank chamber 39 through the passage 41, where the pulsation is attenuated and eliminated, and the supercharged air is transferred to the next fuel such as the carburetor 7. After the fuel is appropriately supplied at the supply point, it is sucked into the combustion chamber of the engine 1, making it possible to prevent fluctuations in the air-fuel ratio during fuel supply and also avoid a decrease in charging efficiency in a specific rotation range. It is. Furthermore, air entering the secondary air chamber 24 from the clean side chamber 22 through the through hole 28 is caused to open and close by the check valve 34 in the secondary air supply passage 35 due to the pulsation of exhaust gas in the exhaust manifold 3. The air is then supplied to the exhaust system as secondary air, and is used to purify the exhaust gas.

In this case, the present invention provides an internal combustion engine 1 having the blower compressor 6 and the air cleaner 11 in the intake system as described above.
1, a ring-shaped filter element 17 is provided in the cleaner case 12, and the outside of the filter element 17 is connected to a dust side chamber 21 communicating with the atmospheric air intake pipe 20, and the inside of the filter element 17 is connected to a clean side chamber 22. A surge tank 39 is provided in the clean side chamber 22 and is separated from the clean side chamber 22 by a partition wall 36. A ring-shaped filter element 17 is inserted into the passage.
Since the clean side chamber 22 inside the air cleaner can be used to install the surge tank 39 for eliminating pulsation, the space required for installing both the air cleaner and the surge tank can be significantly reduced. Moreover, since the bulkhead constituting the surge tank is surrounded by a cleaner case in the air cleaner, the cleaner case prevents the noise generated when eliminating pulsations in the surge tank from being transmitted to the atmosphere. It can be reduced. Moreover, the present invention provides a cleaner case of the air cleaner 11 in which the secondary air supply passage 35 equipped with the check valve 34 of the secondary air supply device utilizing the pulsation of exhaust gas is communicated with the clean side chamber 22 of the air cleaner 11. An intake chamber 23 communicating with the suction side of a supercharger such as the blower compressor, and a secondary air chamber communicating with a secondary air supply passage 35 equipped with a check valve 34 to the exhaust system of the engine 1 are provided on the lower surface of the engine 12. 24, and the intake chamber 23
A through hole 2 communicates between the clean side chamber 22 and the clean side chamber 22.
7, and by separately providing a through hole 28 that communicates the secondary air chamber 24 and the clean side chamber 22, the noise generated when supplying secondary air to the exhaust system is removed from the secondary air chamber 24. The air is transmitted to the clean side chamber 22 through the through hole 28, and from the clean side chamber 22 to the intake chamber 23 through the through hole 27, and then released into the atmosphere from the atmospheric air intake pipe 20. In this case, noise accompanying the supply of secondary air is caused by expansion when transmitted from the secondary air chamber 24 to the clean side chamber 22 via the through hole 28 and transmitted from the clean side chamber 22 to the intake chamber 23 through the through hole 27. Since the noise is attenuated by the two-stage expansion, the noise generated when the secondary air is supplied can be significantly reduced from being emitted into the atmosphere. The exhaust gas that flows back into the secondary air chamber 24 is
It flows into the clean side chamber 22 from the clean side chamber 22 through the through hole 27 to the intake chamber 23, and then passes through a supercharger such as a blower compressor 6 and reaches a fuel supply point such as a carburetor 7. In addition to the fact that the surge tank chamber 39 is located between the through holes 28 and 27 in the clean side chamber 22, the distance from the through hole 28 to the through hole 27 becomes longer. The direct flow of exhaust gas from the through hole 28 to the through hole 27 is blocked by the presence of the surge tank chamber 39, during which the exhaust gas flowing back is allowed to flow through the filter element 17 into the clean side chamber 22. The incoming atmospheric air is mixed,
Since the temperature will drop rapidly, the safety against fire in the intake system will be increased.

Therefore, according to the present invention, a supercharged internal combustion engine is equipped with a supercharger, an air cleaner, a surge tank, and a secondary air supply device using exhaust pulsation in the intake system.
It can be made smaller and lighter, and it can also reduce noise when eliminating pulsation by the surge tank and noise when supplying secondary air to the exhaust system, and also reduce exhaust gas generated when supplying secondary air to the exhaust system. This has the effect of improving safety against fires caused by backflow of water.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a schematic diagram of the entire engine, Fig. 2 is a vertical front view of the air cleaner, and Fig. 3 is a sectional view taken from the - side of Fig. 2. 4 is a cross-sectional view of FIG. 2, FIG. 5 is a cross-sectional view of FIG. 3, FIG. 6 is a cross-sectional view of FIG. 3, and FIG. 7 is a cross-sectional view of FIG. 3. FIG. 8 is a cross-sectional view taken from - in FIG. 3. 1... Engine, 2... Intake manifold, 3...
Exhaust manifold, 4...Exhaust turbo supercharger, 6
...Blower compressor, 11 ...Air cleaner, 1
2...Cleaner case, 17...Filter element, 21...Dust side chamber, 20...Atmospheric air intake pipe, 22...Clean side chamber, 23...
Intake chamber, 24... Secondary air chamber, 27, 28... Through hole, 34... Check valve, 35... Secondary air supply passage, 36... Partition wall, 39... Surge tank.

Claims (1)

[Scope of utility model registration request] In an internal combustion engine having an intake system including a turbocharger and an air cleaner, a ring-shaped filter element is provided in a cleaner case of the air cleaner, the outside of the filter element is formed as a dust side chamber communicating with an intake pipe for atmospheric air, and the inside of the filter element is formed as a clean side chamber, and a surge tank separated from the clean side chamber by a partition is provided in the clean side chamber, and the surge tank is inserted in an intake passage leading from the discharge side of the turbocharger to the engine, and a bottom surface of the cleaner case of the air cleaner is provided with:
An intake device for a supercharged internal combustion engine, comprising an intake chamber communicating with the intake side of the supercharger, and a secondary air chamber communicating with a secondary air supply passage equipped with a check valve to an exhaust system of the engine, and a through hole communicating the intake chamber with the clean side chamber, and a through hole communicating the secondary air chamber with the clean side chamber.