JP5508632B2 - Blow-by gas processing device in an internal combustion engine with an exhaust turbocharger - Google Patents

Description

  The present invention relates to an apparatus for guiding blowby gas collected in a crank chamber and a valve mechanism chamber to an intake passage in an internal combustion engine having an exhaust turbocharger.

  In an internal combustion engine equipped with an exhaust turbocharger, the pressure in the intake path from the blower compressor to the internal combustion engine is higher than atmospheric pressure in the ON turbo state where the exhaust turbocharger is operating. Therefore, in this ON turbo state, it is difficult to guide the blow-by gas to the intake path.

Therefore, Patent Document 1 as the prior art
“In an internal combustion engine configured so that a crank chamber in a cylinder block and a valve mechanism chamber in a cylinder head communicate with each other, an exhaust turbocharger including an exhaust turbine and a blower compressor is provided. A crank chamber is connected to a portion of the intake passage extending from the blower compressor to the internal combustion engine downstream of the throttle valve via a first blow-by gas passage, and into the intake passage in the first blow-by gas passage. The valve mechanism chamber is connected to the air suction passage to the blower compressor through the second blow-by gas passage.
Propose that.

  The prior art utilizes the fact that the portion of the intake path downstream of the throttle valve has a negative pressure lower than the atmospheric pressure in an OFF turbo state where the exhaust turbocharger does not operate, The blow-by gas is guided to the internal combustion engine via the first blow-by gas through the intake path, while fresh air in the air suction passage to the blower compressor is guided to the valve mechanism mechanism chamber via the first blow-by gas. It is configured as follows.

  Further, in the ON turbo state where the exhaust turbocharger is operated, the pressure upstream of the throttle valve in the intake path exceeds the atmospheric pressure and rises to a high supercharging pressure, while the air pressure to the blower compressor is increased. By utilizing the fact that the pressure in the suction passage becomes lower than the pressure in the OFF turbo state as the amount of intake air increases, the blow-by gas in the valve mechanism chamber is passed through the second blow-by gas passage. The structure is such that a check valve provided in the first blow-by gas passage prevents the supercharging pressure downstream from the throttle valve from entering the crank chamber while being guided to the air suction passage to the blower compressor. I have to.

Japanese Utility Model Publication No. 05-087213

  According to the prior art, in the state of OFF turbo, both the crank chamber and the valve mechanism chamber can be reliably ventilated by sucking out blow-by gas from them and introducing fresh air into them. .

  However, on the other hand, in the ON turbo state, introduction of the supercharging pressure in the intake passage into the crank chamber, that is, introduction of fresh air into the crank chamber, is a check provided in the first blow-by gas passage. When the concentration of blow-by gas in the crank chamber and the valve mechanism chamber is in the off-turbo state because it is blocked by a valve and is not ventilated by introducing fresh air into the crank chamber. Therefore, there is a problem that not only the deterioration of the lubricating oil is promoted, but also the deterioration of various rubber products such as sealing gaskets is promoted.

  The present invention has a technical problem to solve this problem.

In order to achieve this technical problem, claim 1
“An internal combustion engine having a first blow-by gas chamber by a crank chamber and a second blow-by gas chamber by a valve operating mechanism chamber, and these blow-by gas chambers communicating with each other, an exhaust turbocharger having an exhaust turbine and a blower compressor An exhaust bypass valve that opens when the pressure on the upstream side of the throttle valve in the intake passage extending from the blower compressor to the internal combustion engine becomes higher. , One of the blowby gas chambers is connected to a portion of the intake passage downstream of the throttle valve via a first blowby gas passage, and the first blowby gas passage is connected to the intake passage. While providing a check valve that opens only in the direction, the other blow-by gas chamber of the two blow-by gas chambers In the atmosphere suction passage to the blower compressor that is connected through the second blow-by gas passage,
The one blowby gas chamber is connected to a pressure transmission passage from the intake passage to the exhaust bypass valve via a boost pressure control passage having a pressure control valve for controlling a boost pressure with respect to the exhaust bypass valve. did. "
It is characterized by that.

Claim 2
“In the first aspect of the present invention, a portion connecting the supercharging pressure control passage to the one blowby gas chamber is separated from a portion communicating with the other blowby gas chamber in the one blowby gas chamber. Located in the site. "
It is characterized by that.

  2. The throttle valve according to claim 1, wherein when the exhaust turbocharger is in an OFF turbo state, the pressure control valve in the supercharging pressure control passage is closed, but the opening of the throttle valve is small, and the throttle valve in the intake passage is small. Since the downstream side has a negative pressure lower than the atmospheric pressure, the blow-by gas in one of the blow-by gas chambers passes through the first blow-by gas passage and the throttle valve in the intake passage. It is sucked into the downstream part and processed.

  Accordingly, the blow-by gas in the other blow-by gas chamber communicating with the one blow-by gas chamber is sucked into the one blow-by gas chamber, and the air to the blower compressor of the exhaust turbocharger is contained in the other blow-by gas chamber. Fresh air in the suction passage will enter through the second blow-by gas passage.

  Thus, both the blow-by gas chambers can be reliably ventilated by sucking out blow-by gas from them and introducing fresh air into them.

  Next, when the exhaust turbocharger is in an ON turbo state, the pressure in the intake passage rises to a high supercharging pressure over the atmospheric pressure, while in the passage for atmospheric suction to the blower compressor. The pressure becomes lower than the pressure in the OFF turbo state as the intake air amount increases.

  When the pressure control valve in the supercharging pressure control passage is opened when a high supercharging pressure is required, such as during acceleration in an internal combustion engine, the supercharging air compressed by the blower compressor However, the blow-by gas existing in one blow-by gas chamber is pushed into the other blow-by gas chamber through the pressure transmission passage and the supercharging pressure control passage, so that the other blow-by gas chamber communicating with the blow-by gas chamber Extruded.

  The blow-by gas pushed out from the one blow-by gas chamber into the other blow-by gas chamber passes through the second blow-by gas passage together with the blow-by gas in the other blow-by gas chamber to the blower compressor. It is sucked into the air suction passage and processed.

  As a result, both of the blow-by gas chambers can be ventilated by pushing in fresh air, and the concentration of the blow-by gas in the blow-by gas chambers can be prevented from becoming high in the ON turbo state. Therefore, deterioration of lubricating oil and various rubber products by blow-by gas can be greatly reduced.

  According to claim 2, fresh air that has entered the one blowby gas chamber from the supercharging pressure control passage reaches a wide area in the one blowby gas chamber and then flows out into the other blowby gas chamber. Therefore, there is an advantage that the ventilation in the one blow-by gas chamber can be effectively performed.

It is a figure which shows embodiment of this invention. It is a figure which shows the state of OFF turbo. It is a figure which shows the state of ON turbo.

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

  In these drawings, reference numeral 1 denotes an internal combustion engine having a plurality of cylinders. The internal combustion engine 1 includes a cylinder block 2, a cylinder head 3 fastened to the upper surface thereof, and a crankcase at a lower portion of the cylinder block 2. 4 is constituted by an oil pan 6 fastened to close the crank chamber 5 on the lower surface of 4 and a head cover 8 fastened to close the valve mechanism chamber 7 on the upper surface of the cylinder head 3.

  The internal combustion engine 1 is provided with an intake manifold 9 for each cylinder and an exhaust manifold 10 for each cylinder. A valve mechanism chamber 7 is connected between the crank chamber 5 and the valve mechanism chamber 7. Are connected to each other by an oil dropping passage 11 from the engine to the crank chamber 5 or a chain cover (not shown) for storing a timing chain.

  The crank chamber 5 has an oil separator 12 for blow-by gas discharged from the crank chamber 5, and the valve mechanism chamber 7 has an oil separator 13 for blow-by gas discharged from the valve mechanism chamber 7. Are provided.

  The inlet to the oil separator 12 in the crank chamber 5 is located in a portion of the crank chamber 5 away from a portion 11a where the oil dropping passage 11 and the like from the valve mechanism chamber 7 are opened.

  Next, reference numeral 14 denotes an exhaust turbocharger formed by directly connecting the exhaust turbine 15 and the blower compressor 16.

  A first exhaust passage 17 from the exhaust manifold 10 is connected to an exhaust turbine 15 of the exhaust turbocharger 14 and a second exhaust passage 18 to the atmosphere is connected to an outlet thereof. An exhaust bypass passage 19 that bypasses the exhaust turbine 15 is provided between the first exhaust passage 17 and the second exhaust passage 18.

  On the other hand, the blower compressor 16 has an air suction passage 21 connected to the air cleaner 20 connected to the suction port, and an intake passage 22 connected to the intake manifold 9 connected to the discharge port. The surge tank 23, the throttle valve 24, and the intercooler 25 are provided so that the surge tank 23 is located on the most downstream side, the throttle valve 24 is located on the upstream side, and the intercooler 25 is located on the most upstream side. It has been.

  A pressure-operated exhaust bypass valve 26 is provided in the exhaust bypass passage 19 for the exhaust turbine 15.

  A valve body 26a in the exhaust bypass valve 26 is connected to a diaphragm 26e that is divided into a first pressure chamber 26c and a second pressure chamber 26d in the actuator 26b, and is normally closed by a spring 26f provided in the first pressure chamber 26c. Is held in.

  While the first pressure chamber 26c communicates with the atmosphere, the pressure in the portion of the intake passage 22 downstream of the blower compressor 16 and upstream of the throttle valve 24 is transferred to the second pressure chamber 26d. 27, when the pressure exceeds a predetermined supercharging pressure higher than the atmosphere, the valve body 26a opens against the spring 26f, so that the pressure becomes a predetermined supercharging pressure. It is configured not to exceed.

  The oil separator 12 in the crank chamber 5 is connected to the surge tank 23 or the first blow-by gas passage 28 to the intake manifold 9, and the first blow-by gas passage 28 is connected to the surge tank 23 or A check valve 29 is provided that opens only in the direction toward the intake manifold 9.

  A second blow-by gas passage 30 to the atmospheric suction passage 21 is connected to the oil separator 13 in the valve mechanism chamber 7.

  A boost pressure control passage 32 having a pressure control valve 31 is connected to the pressure transmission passage 27 from the intake passage 22 to the exhaust bypass valve 26.

  The pressure control valve 31 is provided with a high boost pressure such as during acceleration in the internal combustion engine 1 by a controller 35 that receives signals from an opening sensor 33 of the throttle valve 24 and a rotation sensor 34 in the internal combustion engine 1. The exhaust bypass valve 26 is opened when the exhaust pressure is required, and the exhaust bypass valve 26 is closed to increase the supercharging pressure. When the supercharging pressure exceeds a predetermined value, the exhaust bypass valve 26 is closed to operate. It is configured to open and lower the supercharging pressure.

  The other end 32a of the supercharging pressure control passage 32 is open to a portion of the crank chamber 5 close to the oil separator 12, that is, the oil dropping passage 11 from the valve mechanism chamber 7 of the crank chamber 5 is opened. Connected to a part away from the part 11a.

  In this configuration, when the exhaust turbocharger 14 is in an OFF turbo state, the pressure control valve 31 in the supercharging pressure control passage 32 is closed, while the opening of the throttle valve 24 is small, and the intake passage 22 Among them, since the downstream side of the throttle valve 24 has a negative pressure lower than the atmospheric pressure, the crank chamber 5 and the valve mechanism chamber 7 may be fresh air from the air cleaner 20 or the crank chamber 5 and the valve. The blow-by gas in the mechanism chamber 7 is ventilated by flowing as shown by dotted arrows in FIG.

  In other words, the blow-by gas in the crank chamber 5 passes through the first blow-by gas passage 28 and is sucked into the surge tank 23 or the intake manifold 9 downstream of the throttle valve in the intake passage 22 for processing.

  Accordingly, the blow-by gas in the valve mechanism chamber 7 communicating with the crank chamber 5 is sucked into the crank chamber 5, and the blower compressor 16 of the exhaust turbocharger 14 is placed in the valve mechanism chamber 7. Fresh air in the atmospheric air intake passage 21 enters through the second blow-by gas passage 30.

  Thereby, both the crank chamber 5 and the valve mechanism chamber 7 can be reliably ventilated by sucking out blow-by gas from them and introducing fresh air into them.

  Next, when the exhaust turbocharger 14 is in an ON turbo state, the pressure in the intake passage 22 rises to a high supercharging pressure over the atmospheric pressure, while the air is sucked into the blower compressor 16. The pressure in the working passage 21 becomes lower than the pressure in the OFF turbo state as the intake air amount increases, so that the crank chamber 5 and the valve mechanism chamber 7 are supplied with fresh air or crank from the air cleaner 20. The blow-by gas in the chamber 5 and the valve mechanism chamber 7 is ventilated by flowing as shown by solid line arrows in FIG.

  That is, when the pressure control valve 31 in the supercharging pressure control passage 32 is opened when the supercharging pressure is required when high pressure is required as in the acceleration of the internal combustion engine 1 in the ON turbo state, the blower compression is performed. When the supercharged air compressed by the machine 16 is pushed into the crank chamber 5 through the pressure transmission passage 27 and the supercharging pressure control passage 32, the blow-by gas existing in the crank chamber 5 is , It is pushed out into the valve mechanism chamber 7 communicating therewith.

  The blow-by gas pushed out from the crank chamber 5 into the valve mechanism chamber 7 passes through the second blow-by gas passage 30 together with the blow-by gas in the valve mechanism chamber 7 and passes through the blower compressor. 16 is sucked into the atmospheric suction passage 21 and processed.

  Thus, both the crank chamber 5 and the valve mechanism chamber 7 can be reliably ventilated by pushing in fresh air, and the crank chamber 5 and the valve mechanism chamber 7 are in the ON turbo state. It is possible to prevent the concentration of blow-by gas in the inside from increasing.

  Pushing of fresh air into the crank chamber 5 from the supercharging pressure control passage 32 is away from the portion 11a in the crank chamber 5 where the oil dropping passage 11 and the like from the valve mechanism chamber 7 are opened. As a result, the fresh air that has entered the crank chamber 5 from the supercharging pressure control passage 32 spreads over a wide area in the crank chamber 5, so that ventilation can be effectively performed. .

  In addition, fresh air discharged from the supercharging pressure control passage 32 can be effectively used for ventilation in the crank chamber 5.

  The air pushed into the crank chamber 5 from the supercharging pressure control passage 32 enters the valve mechanism chamber 7 and is separated into gas and liquid by the oil separator 13 in the valve mechanism chamber 7. Since the air is sucked into the blower compressor 16, it is possible to reliably reduce the occurrence of contamination in the blower compressor 16 due to ventilation in the crank chamber 5 due to the opening of the pressure control valve 31, and lubrication. Oil consumption can be reduced.

1 Internal combustion engine 5 Crank chamber (one blow-by gas chamber)
7 Valve mechanism chamber (the other blow-by gas chamber)
DESCRIPTION OF SYMBOLS 11 Oil drop passage 14 Exhaust turbocharger 15 Exhaust turbine 16 Blower compressor 17, 18 Exhaust pipe 19 Exhaust bypass passage 20 Air cleaner 21 Atmospheric suction passage 22 Intake passage 24 Throttle valve 26 Exhaust bypass valve 27 Pressure transmission passage 28 1st blow-by Gas passage 29 Check valve 30 Second blow-by gas passage 31 Pressure control valve 32 Supercharging pressure control passage

Claims (2)

An exhaust turbocharger having a first blow-by gas chamber by a crank chamber and a second blow-by gas chamber by a valve operating mechanism chamber, the two blow-by gas chambers communicating with each other, an exhaust turbine and a blower compressor The exhaust bypass passage that bypasses the exhaust turbine is provided with an exhaust bypass valve that opens when the pressure upstream of the throttle valve in the intake passage from the blower compressor to the internal combustion engine increases. One of the blow-by gas chambers is connected to a portion of the intake passage downstream of the throttle valve via a first blow-by gas passage, and the first blow-by gas passage is directed to the intake passage. One of the blowby gas chambers is provided with a check valve that opens only to the other, and the other blowby gas chamber is The atmosphere suction passage to Lower compressor in those connected through the second blow-by gas passage,
The one blowby gas chamber is connected to a pressure transmission passage from the intake passage to the exhaust bypass valve via a boost pressure control passage having a pressure control valve for controlling a boost pressure with respect to the exhaust bypass valve. An apparatus for treating blow-by gas in an internal combustion engine with an exhaust turbocharger.   2. The part according to claim 1, wherein a portion connecting the supercharging pressure control passage to the one blowby gas chamber is separated from a portion communicating with the other blowby gas chamber in the one blowby gas chamber. An apparatus for treating blow-by gas in an internal combustion engine with an exhaust turbocharger, wherein

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