JP2013256939A - Crank case ventilation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a crank case ventilation device that can suppress the deterioration of engine oil and the lowering of supercharging efficiency.SOLUTION: A crank case ventilation device 10 comprises: a first bypass passage 11 for connecting the upstream side and the downstream side of a supercharger 103; an ejector 12 arranged in the first bypass passage 11; a first flow rate adjusting valve 19 arranged in the first bypass passage 11; a first drive part 20 for driving the first flow rate adjusting valve 19; and an electronic control device 25 which can control a bypass flow rate by controlling the first drive part 20 on the basis of an operation condition of an internal combustion engine 109. Accordingly, since a ventilation volume Qsucked by the ejector 12 can be controlled even if the pressure of a second air intake passage 106 is the same by controlling the bypass flow rate on the basis of the operation condition of the internal combustion engine 109, new air can be introduced into a crank case of the internal combustion engine 109 without excess and insufficiency, and an exhaust gas can be discharged together with a blowby gas.

Description

  The present invention relates to a crankcase ventilation device.

  2. Description of the Related Art Conventionally, a crankcase ventilation device that ventilates the inside of a crankcase by discharging fresh air introduced into the crankcase of an internal combustion engine into a suction air passage together with blow-by gas is known. The crankcase ventilator disclosed in Patent Document 1 is configured such that fresh air in a crankcase is blown together with blow-by gas by an ejector provided in a bypass passage connecting a downstream side and an upstream side of a supercharger in an intake air passage. At the same time as sucking in, new air is introduced into the crankcase. The amount of suction by the ejector, that is, the amount of ventilation, is determined by the flow rate of the fluid flowing through the bypass passage, that is, the bypass flow rate.

JP 2011-94557 A

  In the crankcase ventilation device disclosed in Patent Document 1, the bypass flow rate is determined by the pressure on the downstream side of the supercharger. However, even if the pressure on the downstream side of the supercharger is the same, the amount of blow-by gas generated differs depending on the operating state of the internal combustion engine, and the amount of ventilation by the ejector may be insufficient or excessive. When the ventilation amount is insufficient, fresh air is not introduced into the crankcase, and the engine oil is exposed to blow-by gas, which causes a problem of promoting oil deterioration. On the other hand, when the ventilation amount is excessive, there arises a problem that the reduction in supercharging efficiency is large.

  The present invention has been made in view of the above-described points, and an object of the present invention is to provide a crankcase ventilation device capable of suppressing deterioration of engine oil and suppressing reduction in supercharging efficiency.

  The present invention relates to a crankcase ventilation device that discharges fresh air introduced into a crankcase of an internal combustion engine together with blow-by gas into an intake air passage and simultaneously introduces fresh air into the crankcase. A first bypass passage connecting the upstream side and the downstream side of the turbocharger, an ejector provided in the first bypass passage, a first flow rate adjustment valve provided in the first bypass passage, and a first flow rate adjustment valve It is characterized by comprising a first drive unit that drives, and a flow rate control means that controls the first drive unit based on the operating conditions of the internal combustion engine and can control the flow rate of the fluid flowing through the first bypass passage.

  Therefore, by controlling the flow rate of the fluid flowing through the first bypass passage based on the operating condition of the internal combustion engine, the ventilation amount by the ejector can be controlled regardless of the pressure on the downstream side of the supercharger. It is possible to introduce fresh air without excess or deficiency and to inhale together with blow-by gas. Therefore, it can suppress that engine oil is exposed to blow-by gas, and can suppress deterioration of engine oil. Further, by suppressing the increase in the air pressure in the crankcase, it is possible to suppress the movement of the piston from being inhibited, and to suppress the decrease in the output of the internal combustion engine. Moreover, the fall of the supercharging efficiency resulting from an excessive bypass flow volume can be suppressed.

1 is a diagram showing a schematic configuration of an internal combustion engine and an intake system to which a crankcase ventilation device according to a first embodiment of the present invention is applied. It is an enlarged view which shows the ejector of FIG. 1, and its peripheral part. It is a figure which shows the relationship between the engine speed of the internal combustion engine of FIG. 1, an engine load factor, and blow-by gas generation amount. FIG. 3 is a diagram showing a relationship among an engine speed, an engine load factor, and a pressure between a supercharger and a throttle valve in a second intake air passage of the internal combustion engine of FIG. 1. FIG. 2 is a diagram showing a relationship between an engine speed of the internal combustion engine of FIG. 1, a pressure between a supercharger and a throttle valve in a second intake air passage, and a blow-by gas generation amount. It is a block diagram which shows the function of the electronic control apparatus of FIG. It is a flowchart explaining the control arithmetic processing of the electronic control apparatus of FIG. It is a flowchart explaining the valve opening degree determination process of the electronic controller of FIG. It is a figure which shows the ejector of the crankcase ventilation apparatus by 2nd Embodiment of this invention, and its peripheral part, Comprising: It is a figure when the inlet_port | entrance of a throttle part is fully open. It is a figure when the inlet_port | entrance of the aperture | diaphragm | squeeze part of the ejector of FIG. 9 is half open. FIG. 10 is a view when the inlet of the throttle portion of the ejector of FIG. 9 is fully closed and the outlet of the suction passage is fully open. It is a figure when the exit of the suction passage of the ejector of FIG. 9 is half open. It is a figure when the exit of the suction passage of the ejector of FIG. 9 is fully closed. FIG. 10 is a diagram in which a region diagram showing the suction force of the ejector is superimposed on the diagram showing the relationship between the passage sectional area of the inlet of the ejector and the bypass flow rate in FIG. 9. It is a figure which shows schematic structure of the internal combustion engine and the intake system to which the crankcase ventilation apparatus by 3rd Embodiment of this invention was applied. It is a block diagram which shows the function of the electronic control apparatus of FIG. FIG. 16 is a diagram illustrating a relationship among an engine speed, an engine load factor, and a water vapor concentration in blow-by gas of the internal combustion engine of FIG. 15. It is a flowchart explaining the control arithmetic processing of the electronic control apparatus of FIG. It is a flowchart explaining the valve opening degree determination process of the electronic controller of FIG. It is a figure which shows schematic structure of the internal combustion engine and the intake system to which the crankcase ventilation apparatus by 4th Embodiment of this invention was applied. It is a figure which compares and shows the ejector upstream pressure, bypass flow volume, and ventilation volume when an engine load factor is a predetermined value at the time of steady and acceleration. It is a block diagram which shows the function of the electronic controller of FIG. It is a flowchart explaining the control arithmetic processing of the electronic control apparatus of FIG. It is a flowchart explaining the valve opening degree determination process of the electronic controller of FIG. It is a figure which shows schematic structure of the internal combustion engine and the intake system to which the crankcase ventilation apparatus by 5th Embodiment of this invention was applied. It is a figure which shows schematic structure of the internal combustion engine and the intake system to which the crankcase ventilation apparatus by 6th Embodiment of this invention was applied. It is a block diagram which shows the function of the electronic controller of FIG. It is a flowchart explaining the control arithmetic processing of the electronic control apparatus of FIG. It is a flowchart explaining the valve opening degree determination process of the electronic controller of FIG. It is a figure which shows schematic structure of the internal combustion engine and the intake system to which the crankcase ventilation apparatus by 7th Embodiment of this invention was applied. It is a figure which shows schematic structure of the internal combustion engine and the intake system to which the crankcase ventilation apparatus by 8th Embodiment of this invention was applied. It is a figure which shows the 1st operation position of the needle valve of FIG. It is a figure which shows the 2nd operation position of the needle valve of FIG. It is a figure which shows the 3rd operation position of the needle valve of FIG. It is a figure which shows schematic structure of the internal combustion engine and the intake system to which the crankcase ventilation apparatus by 9th Embodiment of this invention was applied. FIG. 36 is a block diagram illustrating functions of the electronic control device of FIG. 35. It is a flowchart explaining the control arithmetic processing of the electronic control apparatus of FIG. It is a flowchart explaining the valve opening degree determination process of the electronic controller of FIG. It is a figure which shows schematic structure of the internal combustion engine and the intake system to which the crankcase ventilation apparatus by 10th Embodiment of this invention was applied. The temperature of the fluid in the first intake air passage in FIG. 39, the temperature of the fluid upstream of the intercooler in the second intake air passage, and the temperature of the fluid downstream of the intercooler in the second intake air passage. FIG. 6 is a diagram showing the above for each operating condition of the internal combustion engine.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In the embodiments, substantially the same components are denoted by the same reference numerals and description thereof is omitted.
(First embodiment)
The crankcase ventilation apparatus according to the first embodiment of the present invention is applied to the intake system of the internal combustion engine shown in FIG. The intake system 100 passes the air taken into the first intake air passage 102 from the air cleaner 101 and compressed by the supercharger 103 via the second intake air passage 106, the throttle valve 107, and the third intake air passage 108. Supplied to the internal combustion engine 109. The throttle valve 107 can adjust the flow rate of air supplied to the internal combustion engine 109. The first intake air passage 102 corresponds to “upstream of the intake air passage with respect to the supercharger” described in the claims. The second intake air passage 106 corresponds to “between the supercharger and the throttle valve in the intake air passage” recited in the claims. The third intake air passage 108 corresponds to “the downstream side of the intake air passage with respect to the throttle valve” described in the claims.

  The internal combustion engine 109 burns a mixture of air and fuel supplied from the intake system 100 in the combustion chamber 110, and changes the reciprocating motion of the piston 111 due to the explosive force at the time of combustion to rotational motion by the crankshaft 112. The blow-by gas is a gas that has leaked from the combustion chamber 110 into the crankcase 113 during the compression stroke and the combustion stroke of the internal combustion engine 109. This blow-by gas degrades engine oil and causes troubles such as increasing the atmospheric pressure in the crankcase 113 and hindering the movement of the piston 111. Therefore, the crankcase ventilation device 10 sucks fresh air introduced into the crankcase 113 of the internal combustion engine 109 together with the blow-by gas and discharges it into the first intake air passage 102 or the third intake air passage 108, and at the same time, By newly introducing fresh air into the case, the inside of the crankcase 113 is ventilated to prevent the above trouble.

First, the configuration of the crankcase ventilation device 10 will be described. As shown in FIG. 1, the crankcase ventilation device 10 includes a first bypass passage 11, an ejector 12, a gas discharge passage 15, a second bypass passage 16, a fresh air passage 17, an oil separator 18, a first flow rate adjustment valve 19, A first drive unit 20, a first check valve 21, a second flow rate adjustment valve 22, a second drive unit 23, a second check valve 24, and an electronic control device 25 are provided. A white arrow in FIG. 1 indicates a direction in which a fluid mainly composed of fresh air flows, and a hatched arrow in FIG. 1 indicates a direction in which blow-by gas flows.
The first bypass passage 11 connects the housing 105 of the compressor 104 of the supercharger 103 and the first intake air passage 102.
As shown in FIG. 2, the ejector 12 includes a nozzle 36 that constitutes a part of the first bypass passage 11, a throttle passage 13, and a suction passage 14 connected to the throttle passage 13.

Returning to FIG. 1, the gas discharge passage 15 connects the inside of the crankcase 113 and the suction passage 14. The crankcase 113 is a space in which blow-by gas in the internal combustion engine 109 accumulates, and corresponds to a “gas reservoir space” described in the claims.
The second bypass passage 16 connects the downstream side of the first bypass passage 11 to the suction passage 14 and the third intake air passage 108. The passage sectional area of the second bypass passage 16 is set smaller than the passage sectional area of the first bypass passage 11.
The fresh air passage 17 connects the upstream side of the first intake air passage 102 with respect to the first bypass passage 11 and the inside of the head cover 114. The inside of the head cover 114 communicates with the inside of the crankcase 113 through a passage in the cylinder 115 and constitutes a “gas reservoir space”.

The oil separator 18 is provided immediately before the inlet of the gas discharge passage 15 and removes oil from the blow-by gas.
The first flow rate adjusting valve 19 is provided on the upstream side of the suction passage 14 in the first bypass passage 11, and can open and close the first bypass passage 11 so that the opening degree changes continuously.
The first drive unit 20 is, for example, an electromagnetic type, and can open and close the first flow rate adjustment valve 19.
The first check valve 21 is provided on the downstream side of the first bypass passage 11 with respect to the second bypass passage 16 and blocks the flow of fluid from the downstream side to the upstream side.

The second flow rate adjusting valve 22 is provided in the vicinity of the inlet of the suction passage 14 of the ejector 12 and can open and close the suction passage 14 so that the opening degree changes continuously.
The second drive unit 23 is, for example, an electromagnetic type, and can open and close the second flow rate adjustment valve 22.
The second check valve 24 is provided in the vicinity of the inlet of the second bypass passage 16 and blocks the flow of fluid from the downstream side to the upstream side.

The electronic control unit 25 is composed of a microcomputer including a CPU, a RAM, a ROM, an input / output device, and the like, and executes a program process based on detection signals of various sensors, thereby causing the first drive unit 20 and the second drive unit. 23 and the like are controlled.
Detection signals from the engine speed sensor 40, the air flow sensor 41, the throttle sensor 42, the brake sensor 43, and the like are input to the electronic control unit 25. The engine speed sensor 40 detects the engine speed Ne. The air flow sensor 41 detects an intake air amount Qa that is a flow rate of air taken into the intake system 100. The throttle sensor 42 detects the valve opening degree θth of the throttle valve 107. The brake sensor 43 outputs a brake ON signal Bon when a brake (not shown) is operating.

In the internal combustion engine 109, blow-by gas of the amount shown in FIG. 3 is generated according to the engine speed and the engine load factor. The blow-by gas generation amount Qb in FIG. 3 is the flow rate of blow-by gas flowing into the crankcase 113. Here, the pressure of the first intake air passage 102 is P1, the pressure of the second intake air passage 106 is P2, and the pressure of the third intake air passage 108 is P3. As shown in FIG. 5 derived from FIG. 3 and FIG. 4, it can be seen that even if the pressure P2 is the same, the blow-by gas generation amount Qb differs depending on the engine speed Ne.
As shown in FIG. 6, the electronic control unit 25 controls the first drive unit 20 and the second drive unit 23 based on the operating conditions of the internal combustion engine 109 from the relationship shown in FIG. 3, and flows through the first bypass passage 11. It has various functions for controlling a bypass flow rate that is a flow rate of fluid and a ventilation amount Qpcv that is a flow rate of fresh air and blow-by gas flowing through the gas discharge passage 15. The electronic control device 25 functions as a flow rate control means.

The sudden deceleration determination means 26 determines whether or not the vehicle is in a sudden deceleration state based on the valve opening θth of the throttle valve 107 and the brake ON signal Bon.
The load factor calculating means 27 calculates the engine load factor KL based on the intake air amount Qa and the engine speed Ne from the relationship between the intake air amount Qa and the engine speed Ne stored in advance and the engine load factor KL.
The light load determination unit 28 determines whether or not the internal combustion engine 109 is in a light load state based on the engine load factor KL calculated by the load factor calculation unit 27.

The gas amount estimation means 29 estimates the blow-by gas generation amount Qb based on the engine speed Ne and the engine load factor KL from the relationship shown in FIG.
The ventilation amount setting means 30 is based on the blow-by gas generation amount Qb estimated by the gas amount estimation means 29 and the required fresh air amount α, which is a fresh air amount necessary for suppressing deterioration of engine oil, and the target value of the ventilation amount Qpcv. A target ventilation amount Qpcv * is set. In the present embodiment, for example, the target ventilation amount Qpcv * is set from the relationship of the following equation (1).
Qpcv * = Qb + α (1)
When the internal combustion engine 109 is in a light load state, the valve opening degree determining means 31 is based on the target ventilation amount Qpcv * and the second flow rate adjusting valve 22 based on the relationship between the previously stored target ventilation amount Qpcv * and the valve opening degree θ2. Is determined. Further, when the internal combustion engine 109 is not in a light load state, that is, when the internal combustion engine 109 is in a medium load state or a high load state, the valve opening degree determining means 31 is stored in advance with a target ventilation amount Qpcv * and a valve opening degree θ1. Therefore, the valve opening degree θ1 of the first flow rate adjustment valve 19 is determined based on the target ventilation amount Qpcv *.

The first valve fully closing means 32 controls the first drive unit 20 so that the first flow rate adjusting valve 19 is fully closed when the internal combustion engine 109 is in a light load state.
The first valve fully opening means 33 controls the first drive unit 20 so that the first flow rate adjusting valve 19 is fully opened when the vehicle is in a sudden deceleration state.
The second valve fully opening means 34 controls the second drive unit 23 so that the second flow rate adjusting valve 22 is fully opened when the internal combustion engine 109 is in a medium load state or a high load state.
The valve opening degree control means 35 controls the first drive unit 20 based on the valve opening degree θ1 determined by the valve opening degree determination means 31 to control the bypass flow rate, and the valve opening degree determination means 31 determines the valve opening degree determined by the valve opening degree determination means 31. Based on the degree θ2, the second drive unit 23 is controlled to control the ventilation amount Qpcv.

  Next, the control process of the electronic control device 25 will be described with reference to FIGS. FIG. 7 is a main flow of control calculation processing related to flow rate control. The following processing is repeatedly executed at predetermined time intervals from the start of the internal combustion engine 109 to the stop based on a program stored in the ROM of the electronic control unit 25. Various parameters used in the following processing are stored as needed in a storage device such as a RAM, and are updated as necessary.

  When the processing of FIG. 7 starts, first, in step S100, it is determined whether or not the vehicle is in a sudden deceleration state based on the valve opening degree θth of the throttle valve 107 and the brake ON signal Bon. Hereinafter, “step” is omitted, and is simply indicated by the symbol “S”. If the determination in S100 is negative (S100: No), the process proceeds to S110. On the other hand, if the determination in S100 is affirmative (S100: Yes), the process proceeds to S190.

In S110, the engine load factor KL is calculated based on the intake air amount Qa and the engine speed Ne. After S110, the process proceeds to S120.
In S120, it is determined whether the internal combustion engine 109 is in a light load state based on the engine load factor KL. If the determination in S120 is affirmative (S120: Yes), the process proceeds to S130. On the other hand, when determination of S120 is denied (S120: No), a process transfers to S150.

In S130, the flag F = 0. After S130, the process proceeds to S140.
In S140, the first flow rate adjustment valve 19 is fully closed. After S140, the process proceeds to S170.
In S150, the flag F = 1 is set. After S150, the process proceeds to S160.
In S160, the second flow rate adjustment valve 22 is fully opened. After S160, the process proceeds to S170.

In S170, a valve opening determination process for determining the valve opening θ1 of the first flow rate adjustment valve 19 and the valve opening θ2 of the second flow rate adjustment valve 22 is performed. FIG. 8 is a sub-flow showing the valve opening degree determination process. When the processing of FIG. 8 starts, first, in S171, the blow-by gas generation amount Qb is estimated based on the engine speed Ne and the engine load factor KL. After S171, the process proceeds to S172.
In S172, the target ventilation amount Qpcv * is set based on the blow-by gas generation amount Qb. After S172, the process proceeds to S173.

In S173, it is determined whether the flag F is 0 or not. If the determination in S173 is affirmative (S173: Yes), the process proceeds to S174. On the other hand, when the determination in S173 is negative (S173: No), the process proceeds to S175.
In S174, the valve opening degree θ2 of the second flow rate adjustment valve 22 is determined based on the target ventilation amount Qpcv *. After S174, the process exits the series of routines shown in FIG. 8 and returns to the routine shown in FIG.
In S175, the valve opening degree θ1 of the first flow rate adjustment valve 19 is determined based on the target ventilation amount Qpcv *. After S174, the process exits the series of routines shown in FIG. 8 and returns to the routine shown in FIG.

Returning to FIG. 7, after S170, the process proceeds to S180.
In S180, the first flow rate adjustment valve 19 or the second flow rate adjustment valve 22 is controlled based on the valve opening degree θ1 or the valve opening degree θ2. After S180, the process exits the series of routines shown in FIG.
In S190, the first flow rate adjustment valve 19 is fully opened. After S190, the process exits the series of routines shown in FIG.

Next, the operation of the crankcase ventilation device 10 will be described.
(1) Light Load State When the internal combustion engine 109 is in a light load state, the first flow rate adjustment valve 19 is fully closed, and the ejector 12 does not generate a suction force. At this time, the pressure P1 becomes a negative pressure, and the inside of the crankcase 113 is connected to the third intake air passage 108 through the gas discharge passage 15, the first bypass passage 11, and the second bypass passage 16, so The gas is discharged together with fresh air to the third intake air passage 108 via the gas discharge passage 15, the first bypass passage 11 and the second bypass passage 16. The ventilation amount Qpcv is controlled to be (Qpcv> Qb) by adjusting the valve opening degree θ2 of the second flow rate adjustment valve 22 by the electronic control unit 25. Therefore, the ventilation amount Qpcv and the blow-by generation amount Qb Fresh air corresponding to the difference is introduced into the crankcase 113 as needed. Since P2>P1> P3 when the internal combustion engine 109 is in a light load state, the fluid in the first intake air passage 102 tries to flow into the first bypass passage 11, but the inflow is caused by the first check valve 21. It is prevented.

(2) Medium Load State and High Load State When the internal combustion engine 109 is in a medium load state or a high load state, the second flow rate adjustment valve 22 is fully opened, the first flow rate adjustment valve 19 is opened, and the ejector 12 is Generate suction force. Blow-by gas in the crankcase 113 is sucked into the ejector 12 together with fresh air, and is discharged to the first intake air passage 102 along the flow of the first bypass passage 11. The ventilation amount Qpcv is controlled by the electronic control unit 25 so that the valve opening degree θ1 of the first flow rate adjustment valve 19 is adjusted (Qpcv> Qb). Therefore, the ventilation amount Qpcv and the blow-by generation amount Qb Fresh air corresponding to the difference is introduced into the crankcase 113 as needed. Since P2 ≧ P3> P1 when the internal combustion engine is in a medium load state or a high load state, the fluid in the third intake air passage 108 tries to flow into the first bypass passage 11 through the second bypass passage 16. Inflow is prevented by the second check valve 24.

(3) Rapid deceleration state When the vehicle is in a rapid deceleration state, the first flow rate adjustment valve 19 is fully opened, and the rising pressure P2 of the second intake air passage 106 passes through the first bypass passage 11 and the first intake air passage 102. To escape.

As described above, the crankcase ventilation device 10 according to the first embodiment includes the first bypass passage 11 that connects the upstream side and the downstream side of the supercharger 103, and the ejector 12 that is provided in the first bypass passage 11. The first flow rate adjusting valve 19 provided in the first bypass passage 11, the first drive unit 20 that drives the first flow rate adjusting valve 19, and the first drive unit 20 based on the operating conditions of the internal combustion engine 109. And an electronic control unit 25 capable of controlling the bypass flow rate.
Therefore, by controlling the bypass flow rate based on the operating conditions of the internal combustion engine 109, the ventilation amount Qpcv can be controlled regardless of the pressure P2 of the second intake air passage 106, so that fresh air is excessively introduced into the crankcase 113. It can be introduced without any shortage and inhaled with blow-by gas. Therefore, it can suppress that engine oil is exposed to blow-by gas, and can suppress deterioration of engine oil. In addition, a decrease in the output of the internal combustion engine 109 can be suppressed by suppressing an increase in the atmospheric pressure in the crankcase 113. Moreover, the fall of the supercharging efficiency resulting from an excessive bypass flow volume can be suppressed.

  In the first embodiment, the electronic control unit 25 is configured to estimate the blow-by gas generation amount Qb based on the operating conditions of the internal combustion engine 109, and the blow-by gas generation amount estimated by the gas amount estimation unit 29. It has the function of the valve opening degree control means 35 which controls valve opening degree (theta) 1 of the 1st flow regulating valve 19 based on Qb. The operating conditions of the internal combustion engine 109 are the engine speed Ne and the engine load factor KL. Therefore, the ventilation amount Qpcv can be controlled according to the blow-by gas generation amount Qb.

In addition, the crankcase ventilation device 10 according to the first embodiment includes a second bypass passage 16 that connects the downstream side of the first bypass passage 11 to the suction passage 14 and the third intake air passage 108, and a gas discharge passage. 15, a second flow rate adjustment valve 22 that can open and close 15, and a second drive unit 23 that drives the second flow rate adjustment valve 22. The electronic control unit 25 can drive the first drive unit 20 and the second drive unit 23 based on the operating condition of the internal combustion engine 109, and can control the bypass flow rate and the ventilation amount Qpcv.
Therefore, by closing the first flow rate adjustment valve 19 when negative pressure is generated in the third intake air passage 108, blow-by gas and fresh air are supplied to the gas discharge passage 15, the first bypass passage 11, and the second bypass passage 16. Can be discharged to the third intake air passage 108. At this time, since the ventilation amount Qpcv can be controlled by controlling the valve opening degree θ2 of the second flow rate adjustment valve 22, fresh air can be introduced into the crankcase 113 without excess or deficiency.

  Further, in the first embodiment, when the vehicle is determined to be in a sudden deceleration state, the first flow rate adjusting valve 19 is fully opened, so that the pressure P2 that rises between the supercharger 103 and the throttle valve 107 is the first. It is possible to escape to the first intake air passage 102 through the bypass passage 11.

  In the first embodiment, the first bypass passage 11 connects the housing 105 of the supercharger 103 and the first intake air passage 102. Since the pressure in the housing 105 of the supercharger 103 is particularly high between the supercharger 103 and the throttle valve 107, the flow velocity of the fluid passing through the ejector 12 becomes relatively fast, and the suction force of the ejector 12 is increased. be able to.

  Here, since the pressure P3 becomes a negative pressure in the sudden deceleration state, the fluid in the first bypass passage 11 tends to flow into the third intake air passage 108 via the second bypass passage 16. However, in the first embodiment, the passage sectional area of the second bypass passage 16 is smaller than the passage sectional area of the first bypass passage 11. Therefore, when the first flow rate adjustment valve 19 is fully opened during sudden deceleration, most of the fluid in the first bypass passage 11 goes to the first intake air passage 102. Therefore, it is possible to suppress the fluid in the first bypass passage 11 from going to the third intake air passage 108 via the second bypass passage 16, and to suppress the air-fuel mixture of the internal combustion engine 109 from becoming thin.

(Second Embodiment)
A crankcase ventilation apparatus according to a second embodiment of the present invention will be described with reference to FIGS. The crankcase ventilation device 50 includes an ejector 51 instead of the ejector 12 of the first embodiment, and includes the first flow rate adjustment valve 19, the first drive unit 20, the second flow rate adjustment valve 22 and the second drive of the first embodiment. Instead of the part 23, a needle valve 57 and a drive part 60 are provided.
The ejector 51 has a throttle passage 52 that constitutes a part of the first bypass passage 11 and a suction passage 55 that is connected to the throttle passage 52. An outlet 56 of the suction passage 55 opens on the inner wall of the throttle portion 53 of the throttle passage 52.

The needle 58 of the needle valve 57 can be inserted from the upstream side with respect to the throttle portion 53 of the ejector 51, and when inserted until the inlet 54 of the throttle portion 53 is completely closed as shown in FIG. Is fully closed. The needle 58 has a tapered tip 59, and the greater the amount of insertion into the restricting portion 53 from the fully open position shown in FIG. 9 to the fully closed position shown in FIG. The passage sectional area of the inlet 54 of the portion 53 is reduced.
Further, when the needle 58 is inserted until the outlet 56 of the suction passage 55 is completely closed as shown in FIG. 13, the suction passage 55 is fully closed. From the fully open position shown in FIG. 11 through the half-open position shown in FIG. 12 to the fully closed position shown in FIG. 13, the passage sectional area of the outlet 56 of the suction passage 55 is reduced as the amount of insertion into the throttle portion 53 is increased. . The needle valve 57 is an ejector integrated flow control valve.

According to the second embodiment, since the needle valve 57 serves as both the first flow rate adjustment valve and the second flow rate adjustment valve, the number of parts is reduced and the physique can be reduced.
Further, according to the second embodiment, the passage cross-sectional area of the inlet 54 of the throttle portion 53 decreases as the amount of insertion of the needle 58 into the throttle portion 53 increases so that the bypass flow rate decreases, and the passage portion passes through the throttle portion 53. The flow speed of the fluid to be increased. Therefore, the passage sectional area A when the bypass flow rate Qbp is the predetermined value Qbp1 is set to the predetermined value A1, as compared between the solid line indicating the second embodiment in FIG. 14 and the one-dot chain line indicating the first embodiment. In this case, even if the bypass flow rate Qbp is the same value Qbp2, the suction force of the ejector 51 can be increased in the second embodiment.

(Third embodiment)
A crankcase ventilation apparatus according to a third embodiment of the present invention will be described with reference to FIGS. The internal combustion engine 109 has a problem that when the temperature of the inner wall surface of the crankcase 113 is low, water vapor contained in the blow-by gas is likely to condense and the condensed water deteriorates the engine oil. The electronic control device 72 of the crankcase ventilation device 70 shown in FIG. 15 further has a function for preventing the occurrence of condensation in addition to the function of the electronic control device 25 of the first embodiment.
As shown in FIG. 15, the detection signal of the water temperature sensor 71 is input to the electronic control device 72 in addition to the sensors of the first embodiment. The water temperature sensor 71 detects the coolant water temperature Tw of the internal combustion engine 109.

As shown in FIG. 16, the electronic control unit 72 includes a water vapor concentration estimation unit 73, a dew point temperature calculation unit 74, a ventilation volume increase determination unit 75, and a ventilation volume setting unit 76.
The water vapor concentration estimating means 73 estimates the water vapor concentration Cw in the blow-by gas flowing into the crankcase 113 based on the engine speed Ne and the engine load factor KL from the relationship shown in FIG. The water vapor concentration estimating means 73 corresponds to the “gas component estimating means” recited in the claims, and the water vapor concentration Cw corresponds to the “blow-by gas component” recited in the claims.

The dew point temperature calculation means 74 estimates the dew point temperature Tr based on the water vapor concentration Cw from the relationship between the water vapor concentration Cw stored in advance and the dew point temperature Tr.
The ventilation amount increase determination means 75 determines whether or not to increase the ventilation amount Qpcv based on the dew point temperature Tr and the water temperature Tw. When the dew point temperature Tr is higher than the water temperature Tw, it is determined that the ventilation amount Qpcv is increased, and when the dew point temperature Tr is equal to or lower than the water temperature Tw, it is determined that the ventilation amount Qpcv is not increased.

  When the ventilation volume increase determination unit 75 determines that the ventilation volume Qpcv is not increased, the ventilation volume setting unit 76 sets the target ventilation volume Qpcv * as in the ventilation volume setting unit 30 of the first embodiment. When the ventilation volume increase determination means 75 determines to increase the ventilation volume Qpcv, the ventilation volume setting means 76 increases the water vapor so that the target ventilation volume Qpcv * is increased compared to the case where it is determined not to increase the ventilation volume Qpcv. Based on the concentration Cw, blow-by gas generation amount Qb, and water temperature Tw, a target ventilation amount Qpcv * is set.

  Next, control processing of the electronic control unit 72 will be described based on FIGS. 18 and 19. FIG. 18 is a main flow of control calculation processing related to flow rate control. The following processing is repeatedly executed at predetermined time intervals from the start of the internal combustion engine 109 to the stop based on a program stored in the ROM of the electronic control unit 72. Various parameters used in the following processing are stored as needed in a storage device such as a RAM, and are updated as necessary.

In S200 of FIG. 18, a valve opening degree determination process for determining the valve opening degree θ1 of the first flow rate adjustment valve 19 and the valve opening degree θ2 of the second flow rate adjustment valve 22 is performed. FIG. 19 is a subflow showing the valve opening degree determination process. When the processing of FIG. 19 is started, first, in S201, the water vapor concentration Cw in the blow-by gas flowing into the crankcase 113 is calculated based on the engine speed Ne and the engine load factor KL. After S201, the process proceeds to S202.
In S202, the dew point temperature Tr is estimated based on the water vapor concentration Cw. After S202, the process proceeds to S171.

In S203 executed after S171, it is determined whether or not the ventilation amount Qpcv is to be increased based on the dew point temperature Tr and the water temperature Tw. When the dew point temperature Tr is higher than the water temperature Tw, it is determined that the ventilation amount Qpcv is increased, and when the dew point temperature Tr is equal to or lower than the water temperature Tw, it is determined that the ventilation amount Qpcv is not increased. If the determination in S203 is affirmative (S203: Yes), the process proceeds to S204. On the other hand, when the determination in S203 is negative (S203: No), the process proceeds to S172.
In S204, the target ventilation amount Qpcv * is set based on the water vapor concentration Cw, the blow-by gas generation amount Qb, and the water temperature Tw. After S204, the process exits the series of routines shown in FIG. 19 and returns to the routine shown in FIG.

  According to the third embodiment, the target ventilation amount Qpcv * is increased when the dew point temperature Tr of the water vapor in the blow-by gas is higher than the water temperature Tw, so that the water vapor concentration Cw in the blow-by gas can be lowered, and the crankcase Condensation in 113 can be suppressed. Therefore, deterioration of engine oil can be suppressed.

(Fourth embodiment)
A crankcase ventilation apparatus according to a fourth embodiment of the present invention will be described with reference to FIGS.
Consider ventilation of the crankcase 113 during transient operation in which the throttle opening varies with time. FIG. 21 shows the ejector upstream pressure, the bypass flow rate, and the ventilation amount when the engine load factor is a predetermined value in comparison between the steady state and the acceleration state. The ejector upstream pressure is a pressure on the upstream side of the first bypass passage 11 with respect to the ejector 12. As can be seen from FIG. 21, the ejector upstream pressure, the bypass flow rate, and the ventilation amount are all different between the steady state and the acceleration state. That is, even if the operating conditions of the internal combustion engine 109 are the same, the pressure P2 in the second intake air passage 106 and the pressure in the housing 105 of the supercharger 103 differ if the opening speed of the throttle valve 107 is different. Therefore, even when the same amount is ventilated, it is necessary to change the valve opening degree θ1 of the first flow rate adjusting valve 19. The electronic control device 201 of the crankcase ventilation device 200 according to the present embodiment has a function for more accurately ventilating the crankcase 113 during transient operation.

  As shown in FIG. 20, the crankcase ventilation device 200 includes a blow-off passage 202 that connects the second intake air passage 106 and the first intake air passage 102, and a blow-off valve 203 that can open and close the blow-off passage 202. Yes. In this embodiment, the blow-off valve 203 is a mechanical type. Further, the detection signal of the pressure sensor 204 is input to the electronic control unit 201. The pressure sensor 204 is provided on the upstream side of the first bypass passage 11 with respect to the ejector 12, and directly detects the ejector upstream pressure P4. The pressure sensor 204 corresponds to “pressure detection means” and “first pressure sensor” recited in the claims.

As shown in FIG. 22, the electronic control unit 201 includes a valve opening degree determination unit 205 and a valve opening degree control unit 206.
The valve opening degree determining means 205 determines the valve opening degree θ1 based on the target ventilation amount Qpcv * and the ejector upstream pressure P4 from the relationship between the target ventilation amount Qpcv * stored in advance, the ejector upstream pressure P4, and the valve opening degree θ1. To do.
The valve opening degree control means 206 controls the first drive unit 20 based on the valve opening degree θ1 determined by the valve opening degree determination means 205 to control the bypass flow rate and to control the ventilation amount Qpcv.

  Next, control processing of the electronic control device 201 will be described with reference to FIGS. FIG. 23 is a main flow of control calculation processing related to flow rate control. The following processing is repeatedly executed at predetermined time intervals from after the internal combustion engine 109 is started to when it is stopped based on a program stored in the ROM of the electronic control unit 201. Various parameters used in the following processing are stored as needed in a storage device such as a RAM, and are updated as necessary.

  In S220 of FIG. 23, a valve opening determination process for determining the valve opening θ1 of the first flow rate adjustment valve 19 is performed. FIG. 24 is a subflow showing the valve opening degree determination process. In S221 of FIG. 24, the target ventilation amount Qpcv * is set based on the blow-by gas generation amount Qb and the ejector upstream pressure P4. After S221, the process exits the series of routines shown in FIG. 24 and returns to the routine shown in FIG. In S222 of FIG. 23, the first flow control valve 19 is controlled based on the valve opening degree θ2.

According to the fourth embodiment, the first flow control valve 19 can be controlled with an appropriate valve opening θ1, and the crankcase 113 can be more accurately ventilated during transient operation.
Further, according to the fourth embodiment, the pressure P3 in the third intake air passage 108 can be estimated by the pressure sensor 204, and the estimated value can be used for correction of engine control. Therefore, it is not necessary to provide a pressure sensor in the third intake air passage 108.

(Fifth embodiment)
A crankcase ventilation apparatus according to a fifth embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 25, the detection signal of the pressure sensor 212 provided in the second intake air passage 106 is input to the electronic control device 211 of the crankcase ventilation device 210. The pressure P2 of the second intake air passage 106 detected by the pressure sensor 212 can be regarded as the ejector upstream pressure P4. The pressure sensor 212 corresponds to a “first pressure sensor” recited in the claims. The electronic control unit 211 has the same configuration as that of the fourth embodiment except that the pressure P2 is used as the ejector upstream pressure P4.
According to the fifth embodiment, similarly to the fourth embodiment, the first flow control valve 19 can be controlled with an appropriate valve opening degree θ1, and the crankcase 113 can be ventilated more accurately during transient operation. .

(Sixth embodiment)
A crankcase ventilation apparatus according to a sixth embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 26, the detection signal of the pressure sensor 222 provided in the third intake air passage 108 is input to the electronic control device 221 of the crankcase ventilation device 220. The pressure sensor 222 corresponds to a “second pressure sensor” recited in the claims. Further, the pressure P3 of the third intake air passage 108 detected by the pressure sensor 222 corresponds to “a throttle downstream pressure that is a downstream pressure with respect to the throttle valve” recited in the claims.

  As shown in FIG. 27, the electronic control unit 221 has a pressure estimation unit 223. The pressure estimation means 223 estimates the ejector upstream pressure P4 based on the valve opening degree θth, the intake air amount Qa, and the pressure P3. The throttle sensor 42, the air flow sensor 41, the pressure sensor 222, and the pressure estimation means 223 of the electronic control unit 221 constitute “pressure detection means” described in the claims. The electronic control unit 221 has the same configuration as that of the fourth embodiment except that the value estimated by the pressure estimation unit 223 is used as the ejector upstream pressure P4.

  Next, control processing of the electronic control device 221 will be described with reference to FIGS. FIG. 28 is a main flow of control calculation processing related to flow rate control. The following processing is repeatedly executed at predetermined time intervals from after the internal combustion engine 109 is started to when it is stopped based on a program stored in the ROM of the electronic control unit 221. Various parameters used in the following processing are stored as needed in a storage device such as a RAM, and are updated as necessary.

  In S230 of FIG. 28, a valve opening determination process for determining the valve opening θ1 of the first flow rate adjustment valve 19 is performed. FIG. 29 is a subflow showing the valve opening degree determination process. In S231 of FIG. 29, the ejector upstream pressure P4 is estimated based on the valve opening degree θth, the intake air amount Qa, and the pressure P3. After S231, the process exits the series of routines shown in FIG. 29 and returns to the routine shown in FIG.

According to the sixth embodiment, similarly to the fourth embodiment, the first flow control valve 19 can be controlled with an appropriate valve opening θ1, and the crankcase 113 can be ventilated more accurately during transient operation. .
Further, according to the sixth embodiment, since the ejector upstream pressure P4 is estimated by using the pressure sensor 222 provided in the third intake air passage 108, it is necessary to directly measure the ejector upstream pressure. There is no.

(Seventh embodiment)
A crankcase ventilation apparatus according to a seventh embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 30, in the crankcase ventilation device 230, the blow-off passage 231 branches from the upstream side with respect to the ejector 12 in the first bypass passage 11, and the first bypass passage 11 in the first intake air passage 102. A connection is made between the outlet and the supercharger 103.

According to the seventh embodiment, the same effects as in the fourth embodiment can be obtained, and the branch of the blow-off passage 231 from the second intake air passage 106 can be shared with the first bypass passage 11.
In the seventh embodiment, the blow-off passage 231 is connected to the first intake air passage 102 while being branched from the first bypass passage 11. Therefore, in the form in which the blow-off passage 231 is connected downstream of the first bypass passage 11 with respect to the ejector 12, the outlet of the ejector 12 becomes high pressure when the blow-off valve 203 is opened, and the ejector 12 does not function. Alternatively, it is possible to solve the problem that the fluid flows backward in the ejector 12.

(Eighth embodiment)
A crankcase ventilation apparatus according to an eighth embodiment of the present invention will be described with reference to FIGS.
The crankcase ventilation device 240 includes a needle valve 241 and a drive unit 242 instead of the first flow rate adjustment valve 19, the first drive unit 20, and the blow-off valve 203 of the seventh embodiment. The needle 245 of the needle valve 241 can be inserted into the branch portion 243 between the first bypass passage 11 and the blow-off passage 231 from the downstream side of the blow-off passage 231. The drive unit 242 can drive the needle 245 to the first operation position shown in FIG. 32, the second operation position shown in FIG. 33, and the third operation position shown in FIG.

In the first operating position, the needle 245 fully closes the first bypass passage 11 and the blow-off passage 231.
In the second operating position, the needle 245 fully closes the blow-off passage 231 while partially opening the first bypass passage 11. At this time, the drive unit 242 can continuously control the opening degree of the first bypass passage 11 by finely adjusting the position of the needle 245.
In the third operating position, the needle 245 fully opens the first bypass passage 11 and the blow-off passage 231.
According to the eighth embodiment, since the needle valve 241 serves as both the first flow rate adjustment valve and the blow-off valve, the number of parts is reduced and the physique can be reduced.

(Ninth embodiment)
A crankcase ventilation apparatus according to a ninth embodiment of the invention will be described with reference to FIGS. As shown in FIG. 35, the crankcase ventilation device 80 includes a flow meter 81 that can detect a fresh air amount Qn that is a flow rate of fresh air flowing through the fresh air passage 17. A detection signal from the flow meter 81 is input to the electronic control unit 82.
As shown in FIG. 36, the valve opening determining means 83 included in the electronic control unit 82 includes the valve opening θ1 of the first flow rate adjusting valve 19 and the valve of the second flow rate adjusting valve 22 based on the fresh air amount Qn. The opening degree θ2 is controlled. Specifically, the valve opening determining means 83 is a second flow rate adjusting valve so that the fresh air amount Qn detected by the flow meter 81 matches the required fresh air amount α when the internal combustion engine 109 is in a light load state. The valve opening θ2 of 22 is feedback controlled. Further, the valve opening determining means 83 adjusts the first flow rate so that the fresh air amount Qn detected by the flow meter 81 coincides with the required fresh air amount α when the internal combustion engine 109 is in a medium load state or a high load state. The valve opening degree θ1 of the valve 19 is feedback controlled.

  Next, the control process of the electronic control unit 82 will be described with reference to FIGS. FIG. 37 is a main flow of control calculation processing related to flow rate control. The following processing is repeatedly executed at predetermined time intervals from the start of the internal combustion engine 109 to the stop based on a program stored in the ROM of the electronic control unit 72. Various parameters used in the following processing are stored as needed in a storage device such as a RAM, and are updated as necessary.

In S210 of FIG. 37, valve opening determination processing for determining the valve opening θ1 of the first flow rate adjustment valve 19 and the valve opening θ2 of the second flow rate adjustment valve 22 is performed. FIG. 38 is a subflow showing the valve opening degree determination process. When the processing of FIG. 38 is started and the determination in S173 is affirmative (S173: Yes), the valve opening degree θ2 of the second flow rate adjustment valve 22 is set so that the fresh air amount Qn matches the required fresh air amount α in S211. Is feedback controlled. After S211, the process exits the series of routines shown in FIG. 38 and returns to the routine shown in FIG.
When the determination in S173 is negative (S173: No), the valve opening degree θ1 of the first flow rate adjustment valve 19 is feedback-controlled so that the fresh air amount Qn matches the required fresh air amount α in S212. After S212, the process exits the series of routines shown in FIG. 38 and returns to the routine shown in FIG.

  According to the ninth embodiment, by controlling the valve opening degree of each flow rate adjustment valve based on the fresh air amount Qn detected by the flow meter 81, ventilation is accurately performed without having means for estimating the blow-by gas generation amount Qb. The quantity Qpcv can be controlled.

(10th Embodiment)
A crankcase ventilation apparatus according to a tenth embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 39, the crankcase ventilation device 90 includes an electric oil separator 91 provided on the downstream side of the ejector 12 in the first bypass passage 11 instead of the oil separator 18. The electric oil separator 91 collects oil mist contained in blow-by gas, and exhibits a high oil mist separation function by generating corona discharge from an electrode to which a high voltage is applied, and has little pressure loss.

  Here, FIG. 40 shows the temperature T1 of the fluid in the first intake air passage 102, the temperature T2 of the fluid upstream of the intercooler 92 in the second intake air passage 106, and the second intake air passage 106. FIG. 6 is a diagram showing the temperature T3 of the fluid downstream of the intercooler 92 for each operating condition of the internal combustion engine 109. The intercooler 92 corresponds to an “intake air cooling device” recited in the claims. As shown in FIG. 40, only the temperature T2 is always higher than the dew point temperature Tr1 when the amount of moisture contained in the blowby gas is maximum. According to the tenth embodiment, since the first bypass passage 11 is branched from the upstream side of the intercooler 92 in the second intake air passage 106, the temperature of the fluid passing through the electric oil separator 91 is the temperature T2. It is higher than the dew point temperature Tr1. Therefore, it is possible to prevent the discharge from becoming unstable due to condensation of water vapor in the blow-by gas in the vicinity of the electrode of the electric oil separator 91.

(Other embodiments)
In another embodiment of the present invention, the second bypass passage and the second flow rate adjustment valve may not be provided. In this case, the first flow rate adjustment valve may be provided on the downstream side with respect to the ejector.
In another embodiment of the present invention, the blow-by gas generation amount or blow-by gas component may be estimated based on the operating conditions of the internal combustion engine other than the engine speed and the engine load factor.
In another embodiment of the present invention, the required fresh air amount may be a constant value set in advance, or may be a variable value that varies depending on the operating conditions of the internal combustion engine.
In another embodiment of the present invention, the first bypass passage may be connected anywhere in the second intake air passage instead of the turbocharger housing.
In another embodiment of the present invention, the second bypass passage may be branched from the gas discharge passage and connected to the third intake air passage.
In other embodiments of the present invention, the tip of the needle of the needle valve need not be tapered.

In another embodiment of the present invention, in addition to the configurations of the fourth to eighth embodiments, a second flow rate adjusting valve and a second drive unit are provided, and the electronic control unit performs the second drive based on the operating conditions of the internal combustion engine. You may comprise so that a flow volume of the fluid which flows through a gas discharge passage may be controlled by controlling a part.
In another embodiment of the present invention, instead of the water vapor concentration of the blowby gas, the NOx concentration or SOx concentration in the blowby gas or the unburned fuel amount is estimated, and the valve opening is controlled based on the estimated value. Also good.
In the above-described embodiment, the pressure between the supercharger and the throttle valve is released by fully opening the first flow rate adjustment valve when the vehicle is in a sudden deceleration state, but in other embodiments of the present invention, The pressure may be relieved by a mechanical valve that operates mechanically in response to the pressure between the supercharger and the throttle valve. The mechanical valve can be reduced in the number of parts by being integrated with the first flow rate adjusting valve.
The present invention is not limited to the embodiments described above, and can be implemented in various forms without departing from the spirit of the invention.

10, 50, 70, 80, 90, 200, 210, 220, 230, 240 ... crankcase ventilation device 11 ... first bypass passage 12, 51 ... ejector 13 ... throttle passage 14 ... · Suction passage 15 ··· Gas discharge passage 19, 57 ··· First flow rate adjustment valve 20, 60, 242 ··· First drive unit 25, 72, 82 · · · Flow control means

Claims (17)

Crankcase ventilators (10, 50, 70, 80, 90, 200, 210, 220) for discharging blow-by gas in the crankcase (113) of the internal combustion engine (109) to the intake air passages (102, 106, 108), 230, 240)
A first bypass passage (11) connecting between the supercharger (103) and the throttle valve (107) in the intake air passage and an upstream side (102) with respect to the supercharger in the intake air passage. )When,
An ejector (12, 51) having a throttle passage (13, 52) constituting a part of the first bypass passage, and a suction passage (14, 55) connected to the throttle passage;
A gas discharge passage (15) that connects a gas storage space that is a space in which blow-by gas in the internal combustion engine is stored, and the suction passage;
A fresh air passage (17) connecting the upstream side of the intake air passage to the supercharger and the gas reservoir space;
A first flow regulating valve (19, 57) provided in the first bypass passage;
A first drive unit (20, 60, 242) for driving the first flow rate regulating valve;
Flow rate control means (25, 72, 82, 201, 211, 221) capable of controlling the flow rate of the fluid flowing through the first bypass passage based on the operating conditions of the internal combustion engine;
A crankcase ventilation device comprising: The flow rate control means is
A gas amount estimating means (29) for estimating a blow-by gas generation amount based on an operating condition of the internal combustion engine;
Valve opening control means (35, 206) for controlling the first drive unit based on the blow-by gas generation amount estimated by the gas amount estimation means and controlling the valve opening degree of the first flow rate adjustment valve;
The crankcase ventilation device (10, 50, 70, 90, 200, 210, 220, 230, 240) according to claim 1, characterized by comprising:   The crankcase ventilation device (10, 50, 70, 90, 200, 210) according to claim 2, wherein the gas amount estimation means estimates a blow-by gas generation amount based on an engine speed and an engine load factor. 220, 230, 240). Pressure detecting means (41, 42, 204, 212, 222, 223) capable of detecting an ejector upstream pressure (P4) that is an upstream pressure with respect to the ejector;
The crankcase ventilation device (200, 200) according to claim 2 or 3, wherein the valve opening degree control means (206) controls the opening degree of the first flow rate adjusting valve in accordance with the ejector upstream pressure. 210, 220, 230, 240).   The pressure detection means includes a first pressure sensor (204) provided on the upstream side of the intake air passage from the supercharger to the throttle valve or in the first bypass passage with respect to the ejector. 212, 212, 222), the crankcase ventilation device (200, 210, 230, 240) according to claim 4. The pressure detecting means includes
A throttle sensor (42) capable of detecting a throttle opening (θth) which is a valve opening of the throttle valve;
An air flow sensor (41) capable of detecting an intake air amount (Qa) which is a flow rate of air sucked into the intake air passage;
A second pressure sensor (222) provided on the downstream side (108) with respect to the throttle valve in the intake air passage and capable of detecting a throttle downstream pressure (P3) which is a pressure on the downstream side with respect to the throttle valve;
Pressure estimation means (223) for estimating the ejector upstream pressure based on the throttle opening, the intake air amount, and the throttle downstream pressure;
The crankcase ventilator (220) according to claim 4, characterized in that it comprises: Gas component estimating means (73) for estimating a blow-by gas component based on operating conditions of the internal combustion engine,
The valve opening degree control means controls the opening degree of the first flow rate adjustment valve in accordance with the blow-by gas component estimated by the gas component estimation means. Crankcase ventilation device (70) as described.   The crankcase ventilation device (70) according to claim 7, wherein the gas component estimating means estimates a water vapor concentration of blow-by gas as a blow-by gas component based on an engine speed and an engine load factor. A fresh air amount detecting means (81) capable of detecting a flow rate of fresh air flowing through the fresh air passage;
The crankcase ventilation according to claim 1, wherein the flow rate control means (82) controls the opening degree of the first flow rate adjustment valve based on a flow rate of fresh air detected by the fresh air quantity detection means. Device (80). A second bypass passage (16) connecting the downstream side of the first bypass passage with respect to the suction passage and the downstream side (108) of the intake air passage with respect to the throttle valve;
A second flow rate adjustment valve (22) capable of opening and closing the gas discharge passage, the suction passage or the second bypass passage;
A second drive unit (23, 60) for driving the second flow rate adjustment valve,
The first flow rate adjusting valve is provided upstream of the suction passage in the first bypass passage,
The flow rate control means (25, 72, 82) controls the first drive unit and the second drive unit based on operating conditions of the internal combustion engine, and the flow rate of the fluid flowing through the first bypass passage and the gas The crankcase ventilation device (10, 50, 70, 80, 90) according to any one of claims 1 to 9, wherein the flow rate of the fluid flowing through the discharge passage is controllable. A blow-off passage (231) branched from the upstream side to the ejector of the first bypass passage, and connected to the upstream side of the supercharger of the intake air passage while branching from the first bypass passage;
A blow-off valve (203) capable of opening and closing the blow-off passage;
The crankcase ventilation device (230, 240) according to any one of claims 1 to 10, further comprising: The first flow rate adjustment valve and the blow-off valve are constituted by a first needle valve (241) that also serves as a first needle (245),
The first needle is operated by the first drive unit (242) to fully close the first bypass passage and the blow-off passage, and the blow-off passage is fully closed while the first bypass passage is half-opened. The crankcase ventilator (240) according to claim 11, wherein the crankcase ventilator (240) is driven to an operating position where the first bypass passage and the blow-off passage are fully opened. The outlet (56) of the suction passage opens to the inner wall of the throttle portion (53) of the throttle passage,
The first flow rate adjustment valve and the second flow rate adjustment valve are constituted by a needle valve (57) that also serves as a second needle (58),
The second driving unit (60) is also used as the first driving unit (60),
The needle can be inserted from the upstream side with respect to the throttle portion, and when inserted until the inlet (54) of the throttle portion is completely closed, the first bypass passage is fully closed, and the suction passage is further closed. The crankcase ventilation device (50) according to claim 10, wherein the suction passage is fully closed when inserted until the outlet is completely closed.   The crankcase ventilation device according to claim 13, wherein the needle has a tapered tip portion (59), and the passage cross-sectional area of the throttle portion is reduced in accordance with the amount of insertion into the throttle portion. 50).   15. The crankcase ventilation device according to claim 10, wherein a passage sectional area of the second bypass passage is smaller than a passage sectional area of the first bypass passage. 70, 80, 90, 200, 210, 220, 230, 240).   The first bypass passage connects a housing (105) of a compressor (104) of the supercharger and an upstream side of the intake air passage with respect to the supercharger. The crankcase ventilation device according to any one of 15 (10, 50, 70, 80, 90, 200, 210, 220, 230, 240). An electric oil separator (91) provided in the first bypass flow path;
An intake air cooling device (92) provided between the supercharger and the throttle valve in the intake air passage,
The first bypass passage connects between the supercharger and the intake air cooling device in the intake air passage and an upstream side of the intake air passage with respect to the supercharger. Crankcase ventilation device (90) according to any one of the preceding claims.

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