JP2009108716A - Foreign matter removal device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a foreign matter removal device for an internal combustion engine capable of increasing a flow speed of an introduced gas which is introduced into an air intake passage such as an EGR gas, and adequately separating and removing foreign matters such as condensation water from the introduced gas by utilizing a centrifugal force. <P>SOLUTION: The foreign matter removing device 14 for an internal combustion engine 1 includes a cyclone separator 20 which is provided in an EGR duct 11 for introducing the EGR gas which is mixed with an air intake and sucked into a cylinder into an air intake passage 4, imparts a foreign matter removing action which utilizes the centrifugal force to the EGR gas introduced to the inside, discharges obtained foreign matters from an inlet port 24a of a discharge pipe 24, and discharges the remaining EGR gas from an inlet port 22a of an gas discharge pipe 22 into the air intake passage 4. An air intake introduction passage 15 is formed for directing and introducing the air intake from the air intake passage 4 to the inside of the cyclone separator 20, so that the flow speed of the EGR gas directed to the inside of the cyclone separator 20 can be increased. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a foreign matter removing apparatus for an internal combustion engine that separates and removes foreign matter from gas mixed with intake air such as exhaust gas and blow-by gas recirculated from an exhaust passage and sucked into a cylinder.

  Some internal combustion engines perform exhaust gas recirculation (EGR) in which part of exhaust gas is recirculated from an exhaust passage to an intake passage. The exhaust gas recirculated from the exhaust passage (hereinafter sometimes referred to as EGR gas) contains condensed water, and when this condensed water is introduced into the intake passage in a large amount together with the EGR gas, the operating state of the internal combustion engine May become unstable, and corrosion of equipment provided in the intake system, such as a turbocharger compressor or intercooler, may progress. Thus, an internal combustion engine is known in which an arc-shaped portion bent in an arc shape is formed in the intake passage downstream from the EGR gas introduction position, and the condensed water is separated from the intake air using centrifugal force in the arc-shaped portion. (See Patent Document 1). In addition, there are Patent Documents 2 to 4 as prior art documents related to the present invention.

JP 2005-256679 A JP 2001-132555 A JP 2003-97361 A JP-A-11-264312

  In the internal combustion engine of Patent Document 1, since the condensate is separated by applying centrifugal force to the mixed gas that is the intake air after the EGR gas is mixed, the arc-shaped portion is used in the operating state where the flow rate of the mixed gas decreases. In this case, the flow rate of the mixed gas does not increase, and there is a possibility that sufficient centrifugal force cannot be applied to the mixed gas. Therefore, the condensed water may not be sufficiently separated from the mixed gas.

  Therefore, the present invention can increase the flow velocity of the introduced gas introduced into the intake passage such as EGR gas with a relatively simple configuration, and can sufficiently remove foreign substances such as condensed water from the introduced gas by utilizing centrifugal force. An object of the present invention is to provide a foreign matter removing apparatus for an internal combustion engine that can be separated and removed.

  The foreign matter removing apparatus for an internal combustion engine according to the present invention is provided in a gas passage for introducing an introduced gas mixed with intake air and sucked into a cylinder into the intake passage, and uses centrifugal force for the introduced gas introduced into the intake passage. In the foreign matter removal apparatus for an internal combustion engine, the separation means includes a separation means for providing the foreign matter separation action, discharging the obtained foreign matter from the foreign matter discharge port, and discharging the remaining introduced gas from the gas discharge port to the intake passage. The above-described problem is solved by providing an intake air introduction passage for directing and introducing intake air from the intake passage into the separation means so that the flow velocity of the introduced gas guided to the inside of the gas generator is increased. ).

  According to the foreign matter removing apparatus of the present invention, the flow rate of the introduced gas in the separation means can be increased by the intake air introduced into the separation means via the intake introduction passage. Therefore, for example, even when the flow rate of the introduced gas is small, the flow rate of the introduced gas can be increased by the intake air introduced into the separation means, and foreign matters can be sufficiently separated and removed from this introduced gas using centrifugal force. Further, in the foreign matter removing apparatus of the present invention, since the intake air is guided into the separation means through the intake air introduction passage, the flow rate of the introduced gas can be increased with a relatively simple configuration.

  In one form of the foreign matter removing apparatus of the present invention, the flow rate adjusting means for adjusting the flow rate of the intake air introduced into the separation means in the intake air introduction passage, and the flow rate of the introduced gas inside the separation means is a predetermined flow rate. Control means for controlling the operation of the flow rate adjusting means may be further provided as described above (Claim 2). In this case, since the flow rate of the introduced gas inside the separation means can be maintained at a predetermined flow rate or higher, foreign substances can be more reliably separated and removed from the introduced gas in the separation means by appropriately setting the predetermined flow rate. Therefore, it is possible to improve the foreign matter separation efficiency in the separation means.

  In this embodiment, the control means may control the operation of the flow rate adjusting means based on the flow rate of the introduced gas introduced into the separation means. The flow rate of the introduced gas inside the separation means is determined by the flow rate of the introduced gas introduced into the separation means and the flow rate of the intake air. Therefore, by controlling the operation of the flow rate adjusting means in this way, it is possible to guide intake air with an appropriate flow rate into the separation means. When the flow rate of the introduced gas introduced into the separation means is reduced, the flow rate of the introduced gas inside the separation means is lowered. Therefore, the control unit may control the operation of the flow rate adjusting unit so that the flow rate of the intake gas guided into the separation unit increases as the flow rate of the introduced gas guided into the separation unit decreases. Good (Claim 4).

  In one form of the foreign substance removal apparatus provided with the control means, a flow rate equal to or higher than a lower limit value of a flow rate range in which foreign substances are separated from the introduced gas introduced into the separation means may be set as the predetermined flow rate. Item 5). By setting the predetermined flow rate in this way, foreign substances can be reliably separated and removed from the introduced gas by the separation means.

  In one form of the foreign matter removing apparatus of the present invention, a cyclone separator is provided as the separating means, which provides a foreign matter separating action to the introduced gas by swirling the introduced gas along the cylindrical wall surface of the separation chamber. The cyclone separator is connected to the gas passage so that the introduced gas is introduced to the outer peripheral side of the separation chamber, and the intake air is introduced so that the intake air is introduced to the inner peripheral side of the separation chamber. A passage may be connected (Claim 6). By introducing the introduction gas to the outer peripheral side in this way, it is possible to promote the collection of the introduction gas near the wall surface of the separation chamber and the movement of the foreign matter to the outer peripheral side. In addition, by promoting the movement of the foreign matter to the outer peripheral side in this manner, the foreign matter is easily collected on the wall surface, so that the foreign matter separation efficiency can be improved.

  In one form of the foreign matter removing apparatus of the present invention, a throttle valve for adjusting a flow rate of intake air is provided in the intake passage, and the intake introduction passage takes out intake air from an intake passage upstream of the throttle valve and extracts the separation means. The separation means may be connected to the intake passage so that the remaining introduced gas is discharged from the gas discharge port to the intake passage downstream of the throttle valve. Item 7). As is well known, the pressure in the intake passage downstream of the throttle valve during operation of the internal combustion engine is lower than the pressure in the intake passage upstream of the throttle valve. In this embodiment, the intake air is taken out from the intake passage upstream of the throttle valve and the remaining introduced gas is discharged into the intake passage downstream of the throttle valve. Therefore, the intake air is introduced into the separation means by the pressure difference between these intake passages. be able to.

  In this embodiment, the internal combustion engine includes a turbocharger, and the separation means is the remaining introduced gas from the gas discharge port into the intake passage downstream from the throttle valve and upstream from the compressor of the turbocharger. May be connected to the intake passage so as to be discharged. Since the pressure of the intake passage becomes higher downstream of the compressor, by providing a separation means so that the remaining introduced gas is discharged at such a position, the intake air is separated from the intake means using the pressure difference of the intake passage. Can be introduced inside.

  The flow passage cross-sectional area of the intake air introduction passage may be smaller than the flow passage cross-sectional area of a passage through which intake air of a throttle body provided with the throttle valve passes. By setting the flow passage cross-sectional area of the intake introduction passage in this way, the pressure in the intake passage downstream from the throttle valve can be reduced when the throttle valve is closed.

  In one form of the foreign matter removing apparatus of the present invention, the gas passage is an EGR passage communicating the exhaust passage of the internal combustion engine and the intake passage, and the introduced gas is recirculated from the exhaust passage to the intake passage. Exhaust gas may be used (claim 10). EGR gas contains particulate matter (PM) as a foreign substance in addition to condensed water. Therefore, by providing the separating means in the EGR passage, it is possible to suppress introduction of these foreign substances into the intake passage.

  In one form of the foreign matter removing apparatus of the present invention, the gas passage may be a blow-by gas passage communicating the crank chamber of the internal combustion engine and the intake passage, and the introduction gas may be blow-by gas. Item 11). Since oil or the like is contained in the blow-by gas as a foreign matter, it is possible to suppress the oil from being introduced into the intake passage by providing the separating means in the blow-by gas passage.

  As described above, the introduced gas of the present invention includes various gases that are mixed with intake air such as EGR gas and blow-by gas and sucked into the cylinder. Further, the foreign matter of the present invention includes condensed water, PM, oil and the like contained in these gases.

  As described above, according to the foreign matter removing apparatus of the present invention, the flow velocity of the introduced gas can be increased by the intake air introduced into the separation means via the intake air introduction passage. Therefore, it is possible to increase the flow velocity of the introduced gas inside the separation means with a relatively simple configuration. In addition, by increasing the flow rate of the introduced gas in this way, foreign substances such as condensed water can be sufficiently separated and removed from the introduced gas using centrifugal force.

(First form)
FIG. 1 shows an outline of an internal combustion engine incorporating a foreign matter removing apparatus according to a first embodiment of the present invention. An internal combustion engine (hereinafter sometimes referred to as an engine) 1 in FIG. 1 is mounted on a vehicle as a driving power source, and has an engine body 3 having a plurality of (four in FIG. 1) cylinders 2. An intake passage 4 and an exhaust passage 5 connected to each cylinder 2 are provided. The intake passage 4 is provided with an air cleaner 6 for intake air filtration, a throttle valve 7 for adjusting the intake air amount, a compressor 8a of the turbocharger 8, and an intercooler 9 for cooling the intake air. The exhaust passage 5 is provided with a turbine 8b of the turbocharger 8 and a waste gate valve 10 for adjusting the flow rate of the exhaust led to the turbine 8b. The turbocharger 8 is a well-known one in which the turbine wheel of the turbine 8b and the compressor wheel of the compressor 8a are connected by a rotating shaft 8d supported by a bearing provided in the center housing 8c.

  The intake passage 4 and the exhaust passage 5 are connected by an EGR passage 11 for returning a part of the exhaust gas to the intake passage 4 as EGR gas. As shown in FIG. 1, the EGR passage 11 connects the intake passage 4 downstream of the throttle valve 7 and upstream of the compressor 8a and the exhaust passage 5 downstream of the turbine 8b. Therefore, the EGR gas is recirculated to the intake passage 3 between the throttle valve 7 and the compressor 8a. The EGR passage 11 is provided with an EGR cooler 12 for cooling the EGR gas, an EGR valve 13 for adjusting the flow rate of the EGR gas, and a foreign matter removing device 14. The foreign matter removing device 14 is used to guide intake air into the cyclone separator 20 from the cyclone separator 20 as a separating means for separating foreign matter such as condensed water and PM from the EGR gas, and the intake passage 4 upstream from the throttle valve 7. And an intake air introduction passage 15. The intake air introduction passage 15 is provided such that the flow passage cross-sectional area is smaller than the flow passage cross-sectional area of a passage (not shown) through which the intake air of the throttle body 7a in which the throttle valve 7 is provided passes. Thus, since the cyclone separator 20 is provided in the EGR passage 11, the EGR passage 11 corresponds to the gas passage of the present invention, and the EGR gas corresponds to the introduced gas of the present invention.

  The cyclone separator 20 will be described with reference to FIGS. 2 and 3. 2 is an enlarged view of the cyclone separator 20, and FIG. 3 is a view showing a cross section of the cyclone separator 20 taken along line III-III in FIG. The cyclone separator 20 includes a casing 21 and a hollow cylindrical gas discharge pipe 22 provided at the center of the casing 21 so as to protrude into the casing 21. The gas exhaust pipe 22 is connected to the intake passage 4 downstream of the throttle valve 7 and upstream of the compressor 8a via a gas introduction passage 11a (see FIG. 1) forming a part of the EGR passage 11. The casing 21 includes a cylindrical cylindrical portion 21a disposed so as to surround the gas discharge pipe 22, and a funnel-shaped recovery portion 21b continuous below the cylindrical portion 21a. A cylindrical separation chamber 23 is formed in the casing 21 by a cylindrical portion 21a. A discharge pipe 24 for discharging foreign matter is provided at the lower part of the collection unit 21b, and the discharge pipe 24 is connected to a tank (not shown) for storing foreign matter.

  As shown in FIGS. 2 and 3, the cylindrical portion 21a of the casing 21 forms a part of the EGR passage 11 and introduces an EGR gas introduction pipe 25 for introducing EGR gas into the separation chamber 23, and an intake introduction passage. 15 and a suction inlet pipe 26 for introducing the suction air into the separation chamber 23 is connected. The EGR gas introduction pipe 25 is connected to the cylindrical portion 21a so that the EGR gas flows in from the tangential direction of the cylindrical portion 21a as shown by the arrow F1 in FIGS. By connecting the EGR gas introduction pipe 25 in this way, the EGR gas introduced into the separation chamber 23 can be swung along the wall surface 23 a of the separation chamber 23. On the other hand, the intake pipe 26 has a cylindrical portion 21a so that the intake air flows inward from the position where the EGR gas is introduced, that is, near the center line C of the cylindrical portion 21a, as indicated by an arrow F2 in FIG. Connected to. That is, the EGR gas introduction pipe 25 is connected to the cylindrical portion 21 a so that EGR gas is introduced into the outer peripheral side of the separation chamber 23, and the intake air introduction pipe 26 is introduced so that the intake air is introduced into the inner peripheral side of the separation chamber 23. Connected to the cylindrical portion 21a. The intake pipe 26 is connected to the cylindrical portion 21a so that the intake air flows in the same direction as the flow of the EGR gas along the flow of the EGR gas swirling along the wall surface 23a of the separation chamber 23. Has been. By connecting the intake inlet pipe 26 in this way, the flow rate of the EGR gas swirling along the wall surface 23a of the separation chamber 23 can be increased.

  A method for separating and removing foreign matter by the cyclone separator 20 will be described. The EGR gas that has flowed into the separation chamber 23 from the EGR gas introduction pipe 25 swirls along the wall surface 23a of the separation chamber 23 to form a swirling flow S as shown in FIGS. Since the intake air is introduced from the intake air introduction pipe 26 in the same direction as the flow direction of the swirl flow S along the swirl flow S, the speed of the swirl flow S is increased. When the swirl flow S is formed in this way with the EGR gas, foreign matter such as condensed water and PM contained in the EGR gas is attached to the wall surface 23a of the separation chamber 23 using centrifugal force, and the foreign matter is removed. It can be separated and removed from the EGR gas. The foreign matter separated from the EGR gas is discharged to a tank (not shown) through the discharge pipe 24. Therefore, the inlet 24a of the discharge pipe 24 opened to the separation chamber 23 corresponds to the foreign matter discharge port of the present invention. The foreign matter in the tank may be purified by being introduced, for example, upstream of an exhaust purification catalyst provided in the exhaust passage 5 of the engine 1 or may be discarded during maintenance of the engine 1. On the other hand, the remaining EGR gas is introduced into the intake passage 4 through the gas discharge pipe 22 as shown by the arrow F3 in FIG. 2 together with the intake air introduced into the separation chamber 23. Thereby, the inflow of the foreign material to the intake passage 4 can be suppressed. Therefore, it is possible to suppress the operation state of the engine 1 from becoming unstable, and to suppress corrosion of equipment provided in the intake passage 4 such as the compressor 8a and the intercooler 9. By discharging the remaining EGR gas in this way, the inlet 22a of the gas discharge pipe 22 that opens to the separation chamber 23 corresponds to the gas discharge port of the present invention.

  According to the foreign matter removing apparatus 14 of the first embodiment, intake air is introduced into the separation chamber 23 of the cyclone separator 20, and the flow rate of EGR gas in the separation chamber 23 can be increased by this intake air. Therefore, even when the engine 1 is operated in an operation state in which the flow rate of EGR gas is reduced, the cyclone separator 20 can sufficiently separate and remove foreign substances from the EGR gas. Moreover, in this foreign material removal apparatus 14, since the intake air is guided to the separation chamber 23 through the intake air introduction passage 15, the flow rate of EGR gas in the separation chamber 23 can be increased with a relatively simple configuration.

  Since EGR gas is introduced into the separation chamber 23 on the outer peripheral side and intake air is introduced into the inner periphery side, the EGR gas is collected near the wall surface 23a of the separation chamber 23 while increasing the flow rate of the EGR gas by the intake air. The movement to the outer peripheral side can be promoted. Further, by promoting the movement of the foreign matter in this way, the foreign matter is easily collected on the wall surface 23a. Therefore, the foreign substance separation efficiency can be improved.

  Since the intake introduction passage 15 is connected to the intake passage 4 upstream of the throttle valve 7 and the gas exhaust pipe 22 is connected to the intake passage 4 downstream of the throttle valve 7, the intake air is taken in by the pressure difference between the upstream and downstream of the throttle valve 7. Can be introduced into the separation chamber 23. Since the flow passage cross-sectional area of the intake air introduction passage 15 is set smaller than the flow passage cross-sectional area of the passage through which the intake air of the throttle body 7a passes, the intake air passes through the intake air introduction passage 15 when the throttle valve 7 is closed. 7 can be prevented from being guided to the intake passage 14 downstream. Therefore, by closing the throttle valve 7, the pressure in the intake passage 4 downstream from the throttle valve 7 can be reduced.

(Second form)
FIG. 4 shows an outline of an internal combustion engine in which a foreign matter removing apparatus according to the second embodiment of the present invention is incorporated. As shown in FIG. 4, this embodiment is different from the first embodiment in that a flow rate adjusting valve 30 as a flow rate adjusting means for adjusting the flow rate of the intake air introduced into the separation chamber 23 is provided in the intake air introduction passage 15. Since the other points are the same as those of the first embodiment, the same reference numerals are given to the portions common to the first embodiment, and the description thereof is omitted. The flow rate adjusting valve 30 is provided such that the flow rate of the intake air introduced into the separation chamber 23 increases as the opening is changed to the open side.

  The operation of the flow rate adjusting valve 30 is controlled by an engine control unit (ECU) 40. The ECU 40 is configured as a computer including a microprocessor and peripheral devices such as RAM and ROM necessary for its operation, and controls the operation state of the throttle valve 7 and the EGR valve 13 to control the operation state of the engine 1. It is a computer unit.

  The ECU 40 controls the operation of the flow rate adjustment valve 30 so that the flow rate of the EGR gas in the separation chamber 23 is equal to or higher than a predetermined flow rate. By controlling the operation of the flow rate adjustment valve 30 in this way, the ECU 40 functions as the control means of the present invention. As the predetermined flow rate, for example, a lower limit value of a flow rate range in which foreign matter is reliably separated from EGR gas is set. In addition, if it is in this flow velocity range, since a foreign material can be reliably isolate | separated from EGR gas, the value beyond the lower limit of this flow velocity range may be set as a predetermined flow velocity.

  More specifically, the ECU 40 adjusts the opening degree of the flow rate adjusting valve 30 according to the opening degree of the EGR valve 13. When the EGR valve 13 changes to the closed side and the flow rate of EGR gas decreases, the flow rate of the swirling flow S in the separation chamber 23 decreases if the flow rate of the intake air introduced into the separation chamber 23 is the same. Therefore, the ECU 40 adjusts the opening degree of the flow rate adjusting valve 30 so that the flow rate of the intake air introduced into the separation chamber 23 increases when the flow rate of the EGR gas decreases in this way. In this control, for example, the relationship between the opening degree of the EGR valve 13 and the opening degree of the flow rate adjustment valve 30 shown as an example in FIG. 5 is obtained in advance through experiments and stored in the ROM of the ECU 40 as a map. Refer to this. By adjusting the opening degree of the flow rate adjustment valve 30 in this way, the flow rate of the intake air guided to the separation chamber 23 can be increased as the flow rate of the EGR gas guided to the separation chamber 23 decreases.

  According to the second embodiment, since the flow rate of the EGR gas in the separation chamber 23 can be maintained at a predetermined flow rate or higher, the cyclone separator 20 can reliably separate and remove foreign substances from the EGR gas. Therefore, the separation efficiency of foreign matters in the cyclone separator 20 can be improved.

  This invention is not limited to each form mentioned above, It can implement with a various form. For example, an apparatus for separating foreign substances from EGR gas is not limited to a cyclone separator, and various apparatuses that impart a foreign substance separating action to EGR gas using centrifugal force may be used.

  Further, the gas from which foreign matter is removed by the foreign matter removing apparatus of the present invention is not limited to EGR gas, and various gases mixed with intake air and sucked into the cylinder may be applied. An example of such a gas is blow-by gas. Therefore, as shown in FIG. 6, the foreign matter removing device 14 may be provided in the blow-by gas passage 50 that connects the crank chamber (not shown) of the engine body 3 and the intake passage 4. 6 that are the same as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted. In this case, the EGR gas introduction pipe 25 of the cyclone separator 20 in FIG. 2 forms a part of the blow-by gas passage 50. Since the blow-by gas contains oil or the like as a foreign matter, the foreign matter removing device 14 separates and removes the oil from the blow-by gas. By introducing the remaining blow-by gas after separating and removing the oil into the intake passage 4 in this way, the adhesion of oil to the intake passage 4, the compressor 8a, the intercooler 9, and the like can be suppressed. In this case, the blow-by gas passage 50 corresponds to the gas passage of the present invention. In this example as well, a flow rate adjusting valve may be provided in the intake air introduction passage 15 to adjust the flow rate of the intake air introduced into the cyclone separator so that the flow rate of blow-by gas in the cyclone separator is equal to or higher than a predetermined flow rate.

The figure which shows the outline of the internal combustion engine in which the foreign material removal apparatus which concerns on the 1st form of this invention was integrated. The figure which expands and shows a cyclone separator. The figure which shows the cross section of the cyclone separator in the III-III line of FIG. The figure which shows the outline of the internal combustion engine in which the foreign material removal apparatus which concerns on the 2nd form of this invention was integrated. The figure which shows an example of the relationship between the opening degree of an EGR valve, and the opening degree of a flow regulating valve. The figure which shows the other example of the foreign material removal apparatus of this invention.

Explanation of symbols

1 Internal combustion engine 2 Cylinder 4 Intake passage 5 Exhaust passage 7 Throttle valve 7a Throttle body 8 Turbocharger 8a Compressor 11 EGR passage (gas passage)
14 Foreign matter removal device 15 Intake introduction passage 20 Cyclone separator (separation means)
22 Gas exhaust pipe 22a Inlet (gas exhaust port)
23 Separation chamber 23a Wall surface 24 Discharge pipe 24a Inlet (foreign matter discharge port)
30 Flow rate adjusting valve (Flow rate adjusting means)
40 Engine control unit (control means)
50 Blow-by gas passage (gas passage)

Claims (11)

Foreign matter obtained by providing a foreign substance separation action using centrifugal force to the introduced gas introduced into the intake passage, which is introduced into the intake passage and mixed with the intake air and introduced into the intake passage. In the foreign matter removing apparatus for an internal combustion engine comprising a separating means for discharging the foreign matter from the foreign matter discharge port and discharging the remaining introduced gas from the gas discharge port to the intake passage,
Foreign matter removal for an internal combustion engine comprising an intake introduction passage for directing and introducing intake air from the intake passage to the inside of the separation means so as to increase the flow velocity of the introduced gas introduced into the separation means apparatus.   The flow rate adjusting means for adjusting the flow rate of the intake air introduced into the separation means in the intake air introduction passage, and the operation of the flow rate adjusting means so that the flow rate of the introduced gas in the separation means is equal to or higher than a predetermined flow rate. The foreign matter removing apparatus for an internal combustion engine according to claim 1, further comprising control means for controlling.   The foreign matter removing apparatus for an internal combustion engine according to claim 2, wherein the control means controls the operation of the flow rate adjusting means based on the flow rate of the introduced gas introduced into the separation means.   4. The control unit according to claim 3, wherein the control unit controls the operation of the flow rate adjusting unit so that the flow rate of the intake gas guided into the separation unit increases as the flow rate of the introduced gas guided into the separation unit decreases. A foreign matter removing apparatus for an internal combustion engine as described.   The foreign matter of the internal combustion engine according to any one of claims 2 to 4, wherein the predetermined flow velocity is set to a flow velocity equal to or higher than a lower limit value of a flow velocity range in which the foreign matter is separated from the introduced gas introduced into the separation means. Removal device. As the separation means, provided is a cyclone separator that provides a foreign substance separation action to the introduced gas by swirling the introduced gas along the wall surface of the separation chamber formed in a cylindrical shape,
The cyclone separator is connected to the gas passage so that the introduction gas is introduced to the outer peripheral side of the separation chamber, and the intake introduction passage is introduced to the inner peripheral side of the separation chamber. The foreign matter removing apparatus for an internal combustion engine according to any one of claims 1 to 5, which is connected. A throttle valve for adjusting the flow rate of intake air is provided in the intake passage,
The intake introduction passage is provided so as to take out intake air from an intake passage upstream of the throttle valve and introduce it into the separation means,
The internal combustion engine according to any one of claims 1 to 6, wherein the separation unit is connected to the intake passage so that the remaining introduced gas is discharged from the gas discharge port to an intake passage downstream of the throttle valve. Engine foreign matter removal device. The internal combustion engine comprises a turbocharger;
The separation means is connected to the intake passage so that the remaining introduced gas is discharged from the gas discharge port to an intake passage downstream of the throttle valve and upstream of a compressor of the turbocharger. The foreign matter removing apparatus for an internal combustion engine according to claim 7.   The foreign matter removing apparatus for an internal combustion engine according to claim 7 or 8, wherein a flow passage cross-sectional area of the intake air introduction passage is smaller than a flow passage cross-sectional area of a passage through which intake air of a throttle body provided with the throttle valve passes. The gas passage is an EGR passage communicating the exhaust passage of the internal combustion engine and the intake passage,
The foreign matter removing apparatus for an internal combustion engine according to claim 1, wherein the introduced gas is exhaust gas recirculated from the exhaust passage to the intake passage. The gas passage is a blow-by gas passage communicating the crank chamber of the internal combustion engine and the intake passage,
The foreign matter removing apparatus for an internal combustion engine according to any one of claims 1 to 9, wherein the introduced gas is blow-by gas.

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