JP4840248B2 - Intake control device for internal combustion engine - Google Patents

Description

  The present invention relates to an intake control device for an internal combustion engine.

  In the field of internal combustion engines, it is known that the amount of air taken into the combustion chamber increases when the inertial supercharging effect is utilized. In Patent Document 1, in order to increase the amount of air sucked into the combustion chamber as much as possible by using this inertial supercharging effect, two intake passages having different lengths from the surge tank to the combustion chamber are formed, An intake control device for an internal combustion engine is described in which the length of the intake passage from the surge tank to the combustion chamber is switched by a passage length switching valve in accordance with the operating state of the internal combustion engine.

  Further, in the field of internal combustion engines, it is known that combustibility is improved when air flowing into a combustion chamber forms a tumble flow in the combustion chamber. The intake control device for an internal combustion engine described in Patent Document 1 has a tumble switching valve for forming a tumble flow of air in the combustion chamber in the intake passage upstream of the combustion chamber. This tumble switching valve closes the intake passage leaving a partial area when closed, so that air flows only downstream by the side of the tumble switching valve, that is, in a partial area of the intake passage. It is made to flow downstream in a biased form, thereby forming a tumble flow of air in the combustion chamber.

  By the way, in the intake control device of the internal combustion engine described in Patent Document 1, the tumble flow is formed in the combustion chamber by closing the intake passage while leaving a partial region by the tumble switching valve. As in the intake device described in Patent Document 3, the intake passage is divided into two passages by a partition wall, and one passage is closed by a tumble control valve at the upstream end of the partition wall so that only from the other passage is in the combustion chamber. In some cases, air is allowed to flow in, thereby forming a tumble flow of air in the combustion chamber.

Japanese Unexamined Patent Publication No. 7-197823 JP-A-7-197816 JP 2002-70566 A JP 2004-293485 A

  By the way, also in the intake device described in Patent Document 3, two intake passages having different lengths to the combustion chamber are used in order to increase the amount of air sucked into the combustion chamber as much as possible using the inertia supercharging effect. And the length of the intake passage to the combustion chamber is switched by the variable intake length valve according to the operating state of the internal combustion engine.

  However, as in the intake device described in Patent Document 3, the intake passage is divided into two passages by a partition wall, and one passage is closed by a tumble control valve at the upstream end of the partition wall, whereby the air is introduced into the combustion chamber. When adopting a configuration that forms a tumble flow, even if the length of the intake passage to the combustion chamber is switched by the variable intake length valve in order to obtain the inertia supercharging effect, depending on the operating state of the tumble control valve, Since there is a region in which the volume changes greatly in the intake passage to the combustion chamber, a sufficient inertial supercharging effect may not be obtained.

  The object of the present invention is to change the length of the intake passage to the combustion chamber and to divide the internal space of the intake pipe into two intake passages by a partition to form a tumble flow of air in the combustion chamber. In the intake control device for an internal combustion engine employing the above-described configuration, a high inertial supercharging effect is obtained regardless of the operating state of the tumble control valve.

In order to solve the above problems, in the first invention, a surge tank, a first intake passage extending from the surge tank and connected to the combustion chamber, and a first intake passage extending from the surge tank and connected to the first intake passage are connected. A second intake passage, an intake passage length changing valve that closes or opens the first intake passage upstream of the connection portion between the second intake passage and the first intake passage, An internal space of the first intake passage downstream of the connection portion between the intake passage and the first intake passage is divided into two along the axis of the first intake passage to form two divided intake passages. A partition wall disposed in the first intake passage and a tumble control valve for closing or opening one of the divided intake passages, and one of the divided intake passages is closed by the tumble control valve. Sometimes the combustion chamber through the other split intake passage In the intake control device for an internal combustion engine in which the partition wall is arranged in the first intake passage so that the air flowing into the tank forms a tumble flow, the second intake passage from the surge tank to the first intake passage The length is longer than the length from the surge tank to the connection point between the second intake passage and the first intake passage, and the passage sectional area of the second intake passage is from the surge tank to the second intake passage and the first intake passage. The tumble control valve is attached to the partition so as to rotate about a rotation shaft attached to the partition, which is smaller than the passage cross-sectional area of the first intake passage to the connection point with the intake passage. . In the first invention, the tumble control valve has a plate-like valve body that is rotatable about the rotation axis, and when the tumble control valve opens one of the divided intake passages, A plate-like valve body of the tumble control valve is parallel to the partition wall. Furthermore, in the first invention, the second intake passage is connected to the first intake passage from a direction substantially perpendicular to the partition, and the tumble control valve is connected to the second intake passage with respect to the partition. Closing or opening a split intake passage formed on the side opposite to the side connected to the first intake passage, the pivot shaft of the tumble control valve is attached to the combustion chamber side end of the partition wall, When the tumble control valve opens the divided intake passage, the plate-like valve body of the tumble control valve is on the same plane or substantially the same plane as the partition wall.

  According to a second aspect, in the first aspect, the second intake passage is connected to a portion of the first intake passage that is closer to the surge tank than the combustion chamber.

  According to a third aspect, in the second aspect, the second intake passage is connected to a portion of the first intake passage adjacent to the surge tank.

In a fourth invention, in any one of the first to third inventions, the intake passage length changing valve has a plate-like valve body, and the intake passage length changing valve opens the first intake passage. At this time, the plate-like valve element of the intake passage length changing valve is on the same plane or substantially the same plane as the partition wall.

In the fifth aspect, in the fourth invention, when the intake passage length change valve is open the first intake passage, combustion chamber side peripheral edge of the plate-shaped valve element of the intake passage length changing valve said Adjacent to the surge tank side end of the bulkhead.

In the sixth aspect, in the fifth invention, which can be rotated each independently in different regions around the one rotation axis as the center or the common axis of pivotal movement the intake passage length changing valve are adjacent to each other When there are two plate-like valve bodies and the intake passage length changing valve opens the first intake passage, the peripheral portion of one plate-like valve body of the intake passage length changing valve is the surge of the partition wall. Adjacent to the tank side end portion, the peripheral edge portion of the other plate-like valve body of the intake passage length changing valve is adjacent to the surge tank side end surface portion of the second intake passage connected to the first intake passage.

According to a seventh aspect, in any one of the first to sixth aspects, when the engine speed is higher than a predetermined engine speed, air is sucked into the combustion chamber via the first intake passage. Then, air is sucked into the combustion chamber with the help of the inertia supercharging effect, and when the engine speed is lower than the predetermined engine speed, the air is introduced into the combustion chamber via the second intake passage. When the air is taken in, the length of the first intake passage and the cross-sectional area of the first intake passage and the length of the second intake passage and the cross-sectional area of the second intake passage are set so that the air is sucked into the combustion chamber with the help of the inertia supercharging effect. ing.

In an eighth aspect according to any one of the first to seventh aspects, the engine load is lower than a predetermined engine load in an engine load region in which the internal combustion engine is smaller than a full load or a load near the full load. Lean burn combustion is performed in which combustion is performed with the air-fuel ratio of the air-fuel mixture in the combustion chamber being larger than the stoichiometric air-fuel ratio, and the engine load is reduced in the engine load region where the internal combustion engine is smaller than the full load or a load near the full load. When the engine load is higher than the predetermined engine load, the stoichiometric combustion is performed in which the air-fuel ratio of the air-fuel mixture in the combustion chamber is set to the stoichiometric or substantially stoichiometric air-fuel ratio, and the internal combustion engine performs the stoichiometric combustion. The intake passage length change valve opens the first intake passage and the tumble control valve opens the split intake passage, and the internal combustion engine performs lean burn combustion. When the intake passage length changing valve opens the first intake passage and the tumble control valve closes one of the divided intake passages, and the engine load is a full load or a load near the full load, The operation of the intake passage length changing valve and the operation of the tumble control valve are controlled according to the rotational speed.

In the ninth invention, in the eighth invention, when the operation state of the internal combustion engine is divided into a low rotation operation state, a low / medium rotation operation state, a medium / high rotation operation state, and a high rotation operation state in order of increasing engine speed, When the engine load is a full load or a load near the full load and the operating state of the internal combustion engine is in the low rotation operation state, the intake passage length change valve closes the first intake passage and the tumble control valve When the engine load is at or near the full load and the operating state of the internal combustion engine is in the low / medium speed operation state, the intake passage length change valve closes the first intake passage. And the tumble control valve opens the split intake passage, and when the engine load is a full load or a load near the full load and the operating state of the internal combustion engine is in the middle / high rotation operation state, the intake passage length change valve Is opening the first intake passage and the tumble control valve is closing one of the divided intake passages, the engine load is at or near the full load, and the operating state of the internal combustion engine is in the high speed operation state. Sometimes, the intake passage length changing valve opens the first intake passage and the tumble control valve opens the divided intake passage.

  According to the present invention, a high inertial supercharging effect can be obtained regardless of the operating state of the tumble control valve.

  Embodiments of an intake air control apparatus for an internal combustion engine according to the present invention will be described below with reference to the drawings. In the following description, “upper” is expressed as “upper” in the drawing, “lower” is expressed as “lower” in the drawing, and “right” is “right” in the drawing. In the drawing, “left side” is expressed as “left” when viewed in the drawing, and “left and right direction” is expressed as “lateral direction” when viewed in the drawing.

  1 to 4 show a first embodiment of an intake air control apparatus for an internal combustion engine according to the present invention. As shown in FIG. 1, the intake control device of the first embodiment includes a surge tank 1 and an intake pipe (hereinafter referred to as “main”) that extends diagonally to the left from the lower surface of the surge tank 1 and is connected to an intake port 2. 3). The main intake pipe 3 extends substantially straight from the surge tank 1 to the intake port 2 and is connected to the intake port 2 so as to be aligned with the intake port 2. An intake passage (hereinafter referred to as “main intake passage”) 5 extending from the surge tank 1 to the combustion chamber 4 is formed by the main intake pipe 3 and the intake port 2.

  Further, the intake control device has an intake pipe (hereinafter referred to as “sub intake pipe”) 6 that extends from the right side surface of the surge tank 1 and is connected to the main intake pipe 3. The sub-intake pipe 6 changes its direction when it extends substantially straight from the surge tank 1 by a predetermined distance in the right direction, and extends substantially straight to the left. The location of the main intake pipe 3 that is closer to the surge tank 1 than the combustion chamber 4 7, in particular, connected to a location 7 of the main intake pipe 3 adjacent to the surge tank 1. The sub-intake pipe 6 forms an intake passage (hereinafter referred to as “sub-intake passage”) 8 extending from the surge tank 1 to the main intake pipe 3 (that is, the main intake passage 5).

  Note that the length of the sub intake passage 8 from the surge tank 1 to the main intake passage 5 is longer than the length from the surge tank 1 to the connection point S between the sub intake passage 8 and the main intake passage 5. The passage sectional area of the sub intake passage 8 is smaller than the passage sectional area of the main intake passage 5 from the surge tank 1 to the connection point S between the sub intake passage 8 and the main intake passage 5.

  Further, in the main intake pipe 3 upstream of the place where the sub intake pipe 6 is connected to the main intake pipe 3 (hereinafter referred to as “intake pipe connection place”) S, the sub intake pipe 6 rotates about the rotation shaft 9. A valve (hereinafter referred to as “intake passage length changing valve”) 11 having a plate-like valve element 10 for opening and closing the main intake pipe 3 is disposed. The intake passage length change valve 11 shown in FIGS. 1 and 2 is in a state in which the main intake pipe 3 is closed, and the intake passage length change valve 11 shown in FIGS. 3 and 4 has the main intake pipe 3 opened. Is in a state.

  Further, in the main intake passage 5 on the downstream side of the intake pipe connection point S, the internal space of the main intake passage 5 is divided into two along the axis of the main intake passage 5 so as to be divided into two divided intake passages 12 and 13. A partition wall 14 is formed. The partition wall 14 is a flat plate, and is arranged so that the lateral width direction of the plane including the plate is perpendicular or substantially perpendicular to the central axis of the combustion chamber 4. Further, a plate-like valve body that rotates around a rotation shaft 15 attached to the end of the partition wall 14 on the surge tank 1 side and opens or closes one of the divided intake passages 12 is provided. A valve 17 (hereinafter referred to as “tumble control valve”) 17 is disposed. The tumble control valve 17 shown in FIGS. 1 and 3 is in a state where one of the divided intake passages 12 is closed, and the tumble control valve 17 shown in FIGS. 2 and 4 is in a state where the divided intake passage 12 is opened. is there. When the tumble control valve 17 is in the state where the divided intake passage 12 is opened, the plate-like valve body 16 of the tumble control valve 17 is parallel to the partition wall 14 as shown in FIGS. In particular, it is on the same plane or substantially the same plane as the partition wall 14.

  The sub intake pipe 6 is connected to the main intake pipe 3 so that the axis of the sub intake pipe 6 immediately before being connected to the main intake pipe 3 is perpendicular or substantially perpendicular to the lateral width direction of the plane including the partition wall 14. Has been. The sub intake pipe 6 is connected to the main intake pipe 3 from a direction perpendicular or substantially perpendicular to the partition wall 14. The divided intake passage 12 that is opened or closed by the tumble control valve 17 is a divided intake passage on the opposite side of the partition 14 from the side where the sub intake pipe 6 is connected to the main intake pipe 3. In FIG. 1, 18 indicates a fuel injection valve, and 19 indicates an intake valve.

  By the way, when the intake passage length change valve 11 closes the main intake passage 5 and the tumble control valve 17 closes one of the divided intake passages 12 (that is, in the state shown in FIG. 1), Air flows from the surge tank 1 into the main intake passage 5 through the sub intake passage 8 and into the combustion chamber 4 only through the divided intake passage 13 that is not closed by the tumble control valve 17. On the other hand, when the intake passage length change valve 11 closes the main intake passage 5 and the tumble control valve 17 opens the divided intake passage (that is, in the state shown in FIG. 2), the air is It flows from the surge tank 1 into the main intake passage 5 through the sub intake passage 8 and then into the combustion chamber 4 through both divided intake passages 12 and 13.

  When the intake passage length changing valve 11 opens the main intake passage 5 and the tumble control valve 17 closes one of the divided intake passages 12 (that is, when it is in the state shown in FIG. 3), Air mainly flows directly from the surge tank 1 into the main intake passage 5 and then flows into the combustion chamber 4 only through the divided intake passage 13 that is not closed by the tumble control valve 17. Further, when the intake passage length changing valve 11 opens the main intake passage 5 and the tumble control valve 17 opens the divided intake passage 12 (that is, in the state shown in FIG. 4), the air is Primarily, it flows directly from the surge tank 1 into the main intake passage 5 and then flows into the combustion chamber 4 through both divided intake passages 12 and 13.

  The volume of the intake passage through which air passes from the surge tank 1 to the combustion chamber 4 (also referred to as “air passage volume”) is the state shown in FIG. 1 when the intake passage length change valve 11 and the tumble control valve 17 are shown in FIG. 2 is the largest when in the state shown in FIG. 2, next largest when in the state shown in FIG. 3, and smallest when in the state shown in FIG. In other words, the length and passage cross-sectional area of the main intake passage 5 and the length and passage cross-sectional area of the sub intake passage 8 are the same as those shown in FIG. 1 for the intake passage length changing valve 11 and the tumble control valve 17. When the intake passage is longest and the passage sectional area is small, and when the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG. 2, the intake passage is next long and the passage sectional area is small. When the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG. 3, the intake passage is next long and the passage cross-sectional area is reduced, and the intake passage length changing valve 11 and the tumble control valve are When 17 is in the state shown in FIG. 4, it can be said that the intake passage is shortest and the passage sectional area is set to be large.

  As the intake passage is longer and the passage cross-sectional area is smaller, a larger inertial supercharging effect can be obtained at a lower engine speed. That is, the longer the intake passage and the smaller the cross-sectional area of the passage, the lower the tuning engine speed related to so-called intake pulsation. Therefore, when the engine speed is the lowest, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled to the state shown in FIG. 1, the largest inertial supercharging effect is obtained, and the engine speed is the next lowest. In some cases, if the intake passage length change valve 11 and the tumble control valve 17 are controlled to the state shown in FIG. When the engine speed is the next lowest, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled to the state shown in FIG. 3, the largest inertial supercharging effect is obtained, and the engine speed is the highest. If the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG.

  As shown in FIGS. 1 and 3, when the tumble control valve 17 closes one of the divided intake passages 12, the air is only in the divided intake passage that is not closed by the tumble control valve 17. As shown by the reference symbol F in FIG. 5, a tumble flow of air (air mixture) is formed in the combustion chamber 4. In FIG. 5, 20 indicates a cylinder head, 21 indicates a cylinder block, 22 indicates a piston, 23 indicates an exhaust valve, 24 indicates an exhaust port, and 25 indicates a spark plug.

  Next, the control of the intake passage length changing valve 11 and the control of the tumble control valve 17 will be described. When the engine operating state is in the region X shown in FIG. 6 (that is, the region where the engine load is not full load or a load near the full load, the engine speed is relatively low, and the engine load is relatively small) Performs lean burn combustion in which the air-fuel ratio in the combustion chamber 4 is made larger than the stoichiometric air-fuel ratio (lean air-fuel ratio) and combustion is performed, and the engine operating state is the region Y shown in FIG. Is not in the full load or a load in the vicinity of the full load, and the engine speed is relatively high and the engine load is relatively large), the internal combustion engine determines the air-fuel ratio of the air-fuel mixture in the combustion chamber 4 When performing stoichiometric combustion in which combustion is performed at a substantially stoichiometric air-fuel ratio, the intake passage length changing valve 11 and the tumble control valve 17 are controlled as follows.

  That is, when the engine operating state is in the region Y and the internal combustion engine is performing stoichiometric combustion, as shown in FIG. 4, the intake passage length changing valve 11 opens the main intake passage 5, The tumble control valve 17 opens the divided intake passage 12. That is, when the internal combustion engine performs stoichiometric combustion, the engine load is relatively large. Therefore, it is necessary to relatively increase the amount of air taken into the combustion chamber 4 (hereinafter referred to as “intake amount”). Here, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, air can be introduced into the combustion chamber 4 through the entire main intake passage 5, so that a so-called pumping loss is small. Therefore, the intake amount becomes relatively large.

  On the other hand, when the engine operating state is in the region X and the internal combustion engine is performing lean burn combustion, the intake passage length changing valve 11 opens the main intake passage 5 as shown in FIG. The tumble control valve 17 closes one of the divided intake passages 12. That is, when the internal combustion engine performs lean burn combustion, since the engine load is relatively small, it is not necessary to increase the intake amount so much, but it is necessary to perform combustion well with a small amount of fuel. Here, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, air can be introduced into the combustion chamber 4 only through one of the divided intake passages 12, so that FIG. As shown, a tumble flow of air (air mixture) is formed in the combustion chamber 4 and the mixing of fuel and air is promoted. Therefore, even if the amount of fuel is small, the combustion is performed well.

  Further, as shown in FIG. 6, the region where the engine load is at the full load or the load near the full load is the low rotation region Z1, the low / medium rotation region Z2, the medium / high rotation region Z3, the high rotation region In the case where the engine operating state is in these regions Z1 to Z4 in the case of dividing into Z4, the internal combustion engine converts the air-fuel mixture in the combustion chamber 4 to a stoichiometric air-fuel ratio, a substantially stoichiometric air-fuel ratio, or an air-fuel ratio (rich) In the case of performing full load combustion in which combustion is performed as an air-fuel ratio), the intake passage length changing valve 11 and the tumble control valve 17 are controlled as follows.

  That is, when the engine operating state is in the low rotation region Z1 and the internal combustion engine is performing full load combustion, the intake passage length changing valve 11 closes the main intake passage 5 as shown in FIG. The tumble control valve 17 closes one of the divided intake passages 12. That is, when the internal combustion engine performs full load combustion, the engine load is very large, and therefore it is necessary to increase the intake air amount as much as possible. Here, when the engine operating state is in the low rotation region Z1, the shape of the intake passage (the shape of the intake passage through which the air flows from the surge tank 1 to the combustion chamber 4) is possible from the relationship with the engine speed. As long as the intake passage is long and the passage cross-sectional area is small, an inertial supercharging effect can be obtained and the intake air amount can be very large. Therefore, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage is the longest intake passage and the sectional area of the passage is small. A large amount of air can flow into the combustion chamber 4.

  Further, when the engine operating state is in the low / medium rotation region Z2 and the internal combustion engine is performing full load combustion, the intake passage length changing valve 11 is connected to the main intake passage 5 as shown in FIG. It is closed so that the tumble control valve 17 opens the divided intake passage 12. That is, when the internal combustion engine performs full load combustion, the engine load is very large, and therefore it is necessary to increase the intake air amount as much as possible. Here, when the engine operating state is in the low / medium speed range Z2, if the shape of the intake passage is the second longest and the cross-sectional area of the passage is small from the relationship with the engine speed, the inertia boost effect Is obtained, and the amount of air becomes very large. Therefore, as described above, when the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage is the second longest intake passage and the sectional area of the passage is small. A very large amount of air can flow into the combustion chamber 4.

  Further, when the engine operating state is in the middle / high rotation region Z3 and the internal combustion engine is performing full load combustion, the intake passage length changing valve 11 opens the main intake passage 5 as shown in FIG. The tumble control valve 17 closes one of the divided intake passages 12. That is, when the internal combustion engine performs full load combustion, the engine load is very large, and therefore it is necessary to increase the intake air amount as much as possible. Here, when the engine operating state is in the middle / high rotation range Z3, if the shape of the intake passage is the third longest intake passage and the sectional area of the passage is small from the relationship with the engine speed, the inertia supercharging effect is obtained. Is obtained and the amount of air is very large. Therefore, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage is the third longest intake passage and the smaller cross-sectional area. A very large amount of air can flow into the combustion chamber 4.

  Further, when the engine operating state is in the high speed region Z4 and the internal combustion engine is performing full load combustion, the intake passage length changing valve 11 opens the main intake passage 5 as shown in FIG. The tumble control valve 17 opens the divided intake passage 12. That is, when the internal combustion engine performs full load combustion, the engine load is very large, and therefore it is necessary to increase the intake air amount as much as possible. Here, when the engine operating state is in the high rotation region Z4, if the shape of the intake passage is made as short as possible and the cross-sectional area of the passage is large from the relationship with the engine speed, the inertia supercharging effect can be obtained. As a result, the intake air amount becomes very large. Therefore, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage becomes the shape with the shortest intake passage and the largest passage cross-sectional area. A large amount of air can flow into the combustion chamber 4.

  When the main intake passage 5, the sub intake passage 8, the intake passage length change valve 11, and the tumble control valve 17 are configured and arranged as in this embodiment, the intake passage from the surge tank 1 to the combustion chamber 4 is arranged. Therefore, there is no or almost no region where the volume changes greatly, so that a higher inertial supercharging effect can be obtained.

  Next, a second embodiment of the intake control device for an internal combustion engine of the present invention will be described. 7 to 10 show a second embodiment. The main intake passage 5 and the sub intake passage 8 of the present embodiment are configured in the same manner as in the first embodiment. However, the configuration of the partition wall 14, the intake passage length changing valve 11, and the tumble control valve 17 of the present embodiment is different from that of the first embodiment.

  In other words, the intake passage length changing valve 11 of the present embodiment has a rotating shaft in the main intake pipe 3 upstream of the intake pipe connection portion (the portion where the sub intake pipe 6 is connected to the main intake pipe 3) S. The main intake pipe 3 is arranged so as to open and close by rotating about the center 9, but there are two types that can rotate independently in different areas with the rotation axis 9 as a common rotation axis. Plate-shaped valve bodies 10A and 10B are provided. The intake passage length change valve 11 shown in FIGS. 7 and 8 is in a state where the main intake pipe 3 is closed, and the intake passage length change valve 11 shown in FIGS. 9 and 10 opens the main intake pipe 3. Is in a state.

  Further, in the main intake passage 5 on the downstream side of the intake pipe connection point S, the internal space of the main intake passage 5 is divided into two along the axis of the main intake passage 5 to form two divided intake passages. A partition wall 14 is disposed. The partition wall 14 is a flat plate, and is arranged so that the lateral width direction of the plane including the plate is perpendicular or substantially perpendicular to the central axis of the combustion chamber 4. Further, the partition wall 14 has a peripheral portion of one valve body 10A of the intake passage length change valve 11 adjacent to the end portion on the surge tank 1 side of the partition wall 14 when the intake passage length change valve 11 is in the state shown in FIG. Thus, it extends toward the surge tank 1.

  Further, the plate-like valve body 16 of the tumble control valve 17 is rotated around a rotating shaft 15 attached to a portion of the intermediate portion of the partition wall 14, in particular, a portion of the surge tank 1 slightly from the intermediate portion of the partition wall 14. It is arranged so as to open and close one of the divided intake passages 12 by moving. The tumble control valve 17 shown in FIGS. 7 and 9 is in a state where one of the divided intake passages 12 is closed, and the tumble control valve 17 shown in FIGS. 8 and 10 is in a state where the divided intake passage 12 is opened. is there. When the tumble control valve 17 is in the state where the divided intake passage 12 is opened, the plate-like valve body of the tumble control valve 17 is parallel to the partition wall 14 as shown in FIGS. In particular, it is on the same plane as the partition wall 14 or substantially on the same plane.

  The divided intake passage 12 that is opened and closed by the tumble control valve 17 is a divided intake passage on the opposite side of the partition 14 from the side where the sub intake pipe 6 is connected to the main intake pipe 3. Further, when the intake passage length changing valve 11 is in the state shown in FIG. 10, it is parallel to the partition wall 14, and in particular, is on the same plane or substantially the same plane as the partition wall 14.

  When the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG. 7, air flows from the surge tank 1 into the main intake passage 5 via the sub intake passage 8, and the tumble control is performed. It flows into the combustion chamber 4 through only the divided intake passage 13 that is not closed by the valve 17. On the other hand, when the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG. 8, air flows from the surge tank 1 into the main intake passage 5 via the sub intake passage 8 and is divided into both parts. It flows into the combustion chamber 4 through the intake passages 12 and 13. When the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG. 9, air mainly flows directly into the main intake passage 5 and is not closed by the tumble control valve 17. Flows into the combustion chamber 4 only through the divided intake passage 13 on the other side. When the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG. 10, the air mainly flows directly from the surge tank 1 into the main intake passage 5, and the both divided intake passages 12. , 13 flows into the combustion chamber 4.

  The shape of the intake passage (the shape of the intake passage through which air flows until it flows into the combustion chamber 4 from the surge tank 1) is when the intake passage length change valve 11 and the tumble control valve 17 are in the state shown in FIG. When the intake passage is the longest and the passage cross-sectional area is small and the state shown in FIG. 8 is the next, the intake passage is the next longest and the cross-sectional area is small, and when it is in the state shown in FIG. The passage cross-sectional area is long and small, and when it is in the state shown in FIG. 10, the intake passage is shortest and the passage cross-sectional area is large.

  As shown in FIGS. 7 and 9, when the tumble control valve 17 closes one of the divided intake passages 12, the air is not closed by the tumble control valve 17. As described with reference to the first embodiment, a tumble flow of air (air mixture) is formed in the combustion chamber 4 as described above in connection with the first embodiment.

  Next, the control of the intake passage length changing valve 11 and the control of the tumble control valve 17 will be described. When the engine operating state is in the region Y shown in FIG. 6 and the internal combustion engine is performing stoichiometric combustion, the intake passage length changing valve 11 opens the main intake passage 5 as shown in FIG. The tumble control valve 17 opens the divided intake passage 12. That is, when the internal combustion engine performs stoichiometric combustion, it is necessary to relatively increase the intake amount (the amount of air sucked into the combustion chamber 4), but as described above, the intake passage length change valve 11 and the tumble If the control valve 17 is controlled, air can flow into the combustion chamber 4 through the entire main intake passage 5, so that the so-called pumping loss is reduced and the intake air amount is relatively increased.

  On the other hand, when the engine operating state is in the region X shown in FIG. 6 and the internal combustion engine is performing lean burn combustion, as shown in FIG. 5 is opened so that the tumble control valve 17 closes one of the divided intake passages 12. That is, when the internal combustion engine performs lean burn combustion, it is not necessary to increase the intake air amount so much, but it is necessary to perform combustion well with a small amount of fuel. Therefore, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, air can flow into the combustion chamber 4 only through one of the divided intake passages 12. In this way, a tumble flow of air (air mixture) is formed, and the mixing of fuel and air is promoted. Therefore, even if the amount of fuel is small, the combustion is performed well.

  Further, when the engine operating state is in the low rotation region Z1 shown in FIG. 6 and the internal combustion engine is performing full load combustion, as shown in FIG. The intake passage 5 is closed so that the tumble control valve 17 closes one of the divided intake passages 12. That is, when the internal combustion engine performs full load combustion, it is necessary to increase the intake amount as much as possible. Here, when the engine operating state is in the low rotation region Z1, the shape of the intake passage (the shape of the intake passage through which the air flows from the surge tank 1 to the combustion chamber 4) is possible from the relationship with the engine speed. As long as the intake passage is long and the passage cross-sectional area is small, an inertial supercharging effect can be obtained and the intake air amount can be very large. Therefore, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage is the longest intake passage and the sectional area of the passage is small. A large amount of air can flow into the combustion chamber 4.

  Further, when the internal combustion engine is in the low / medium rotation region Z2 shown in FIG. 6 and the internal combustion engine is performing full load combustion, as shown in FIG. The intake passage 5 is closed so that the tumble control valve 17 opens the divided intake passage 12. That is, when the internal combustion engine performs full load combustion, it is necessary to increase the intake amount as much as possible. Here, when the engine operating state is in the low / medium speed range Z2, if the shape of the intake passage is the second longest and the cross-sectional area of the passage is small from the relationship with the engine speed, the inertia boost effect Is obtained, and the amount of intake is greatly increased. Therefore, as described above, when the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage is the second longest intake passage and the sectional area of the passage is small. A very large amount of air can flow into the combustion chamber 4.

  Further, when the engine operating state is in the middle / high rotation range Z3 shown in FIG. 6 and the internal combustion engine is performing full load combustion, as shown in FIG. The intake passage 5 is opened so that the tumble control valve 17 closes one of the divided intake passages 12. That is, when the internal combustion engine performs full load combustion, it is necessary to increase the intake amount as much as possible. Here, when the engine operating state is in the middle / high rotation range Z3, if the shape of the intake passage is the third longest intake passage and the sectional area of the passage is small from the relationship with the engine speed, the inertia supercharging effect is obtained. Is obtained and the amount of air is very large. Therefore, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage is the third longest intake passage and the smaller cross-sectional area. A very large amount of air can flow into the combustion chamber 4.

  Further, when the engine operating state is in the high rotation region Z4 shown in FIG. 6 and the internal combustion engine is performing full load combustion, as shown in FIG. The intake passage 5 is opened so that the tumble control valve 17 opens the divided intake passage 12. That is, when the internal combustion engine performs full load combustion, it is necessary to increase the intake amount as much as possible. Here, when the engine operating state is in the high rotation region Z4, if the shape of the intake passage is made as short as possible and the cross-sectional area of the passage is large from the relationship with the engine speed, the inertia supercharging effect can be obtained. As a result, the intake air amount becomes very large. Therefore, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage becomes the shape with the shortest intake passage and the largest passage cross-sectional area. A large amount of air can flow into the combustion chamber 4.

  When the main intake passage 5, the sub intake passage 8, the intake passage length change valve 11, and the tumble control valve 17 are configured and arranged as in this embodiment, the intake passage from the surge tank 1 to the combustion chamber 4 is arranged. Therefore, there is no or almost no region where the volume changes greatly, so that a higher inertial supercharging effect can be obtained. In particular, in the first embodiment, when the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG. 1, the region indicated by reference sign W1 is a region where the volume of the intake passage changes greatly ( However, in the second embodiment, as shown in FIG. 7, since a region in which the volume of the intake passage greatly changes does not occur, a higher inertial supercharging effect can be obtained. I can get it.

  Next, a third embodiment of the intake control device for an internal combustion engine of the present invention will be described. A third embodiment is shown in FIGS. The main intake passage 5, the sub intake passage 8, the intake passage length changing valve 11, and the partition wall 14 of the present embodiment are configured in the same manner as in the second embodiment. However, the configuration of the tumble control valve 17 of this embodiment is different from that of the second embodiment.

  That is, the plate-like valve body 16 of the tumble control valve 17 rotates about a rotation shaft 15 attached to a portion adjacent to the end of the partition wall 14 on the combustion chamber 4 side, and is divided into one divided intake passage 12. Are arranged to open and close. The tumble control valve 17 shown in FIGS. 11 and 13 is in a state in which one of the divided intake passages 12 is closed, and the tumble control valve 17 shown in FIGS. 12 and 14 is in a state in which the divided intake passage 12 is opened. is there. When the tumble control valve 17 is in the state where the divided intake passage 12 is opened, the plate-like valve body 16 of the tumble control valve 17 is parallel to the partition wall 14 as shown in FIGS. In particular, it is on the same plane or substantially the same plane as the partition wall 14.

  11 and 12 is in a state where the main intake pipe 3 is closed, and the intake passage length change valve 11 shown in FIGS. 13 and 14 is connected to the main intake pipe 3. In the open state. The divided intake passage 12 that is opened or closed by the tumble control valve 17 is a divided intake passage on the opposite side of the partition 14 from the side where the sub intake pipe 6 is connected to the main intake pipe 3.

  When the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG. 11, air flows from the surge tank 1 into the main intake passage 5 via the sub intake passage 8, and the tumble control is performed. It flows into the combustion chamber 4 through only the divided intake passage 13 that is not closed by the valve 17. On the other hand, when the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG. 12, air flows from the surge tank 1 into the main intake passage 5 via the sub intake passage 8 and is divided into both parts. It flows into the combustion chamber 4 through the intake passages 12 and 13. When the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG. 13, air mainly flows directly into the main intake passage 5 and is not closed by the tumble control valve 17. Flows into the combustion chamber 4 only through the divided intake passage 13 on the other side. When the intake passage length changing valve 11 and the tumble control valve 17 are in the state shown in FIG. 14, the air mainly flows directly from the surge tank 1 into the main intake passage 5, and the both divided intake passages 12. , 13 flows into the combustion chamber 4.

  The shape of the intake passage (the shape of the intake passage through which the air passes from the surge tank 1 to the combustion chamber 4) is when the intake passage length change valve 11 and the tumble control valve 17 are in the state shown in FIG. When the intake passage is longest and the passage cross-sectional area is small, the intake passage is next long when the passage cross-sectional area is small, and when it is in the state shown in FIG. The passage cross-sectional area is long and small, and when it is in the state shown in FIG. 14, the intake passage is shortest and the passage cross-sectional area is large.

  As shown in FIGS. 11 and 13, when the tumble control valve 17 closes one of the divided intake passages 12, the air is not closed by the tumble control valve 17. As described with reference to the first embodiment, a tumble flow of air (air mixture) is formed in the combustion chamber 4 as described above in connection with the first embodiment.

  Next, the control of the intake passage length changing valve 11 and the control of the tumble control valve 17 will be described. When the engine operating state is in the region Y shown in FIG. 6 and the internal combustion engine is performing stoichiometric combustion, the intake passage length changing valve 11 opens the main intake passage 5 as shown in FIG. The tumble control valve 17 opens the divided intake passage 12. That is, when the internal combustion engine performs stoichiometric combustion, it is necessary to relatively increase the intake amount (the amount of air sucked into the combustion chamber 4), but as described above, the intake passage length change valve 11 and the tumble If the control valve 17 is controlled, air can flow into the combustion chamber 4 through the entire main intake passage 5, so that the so-called pumping loss is reduced and the intake air amount is relatively increased.

  Further, when the engine operating state is in the region X shown in FIG. 6 and the internal combustion engine is performing lean burn combustion, as shown in FIG. 13, the intake passage length changing valve 11 is connected to the main intake passage. 5 is opened so that the tumble control valve 17 closes one of the divided intake passages 12. That is, when the internal combustion engine performs lean burn combustion, it is not necessary to increase the intake air amount so much, but it is necessary to perform combustion well with a small amount of fuel. Therefore, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, air can flow into the combustion chamber 4 only through one of the divided intake passages 12. In this way, a tumble flow of air (air mixture) is formed, and the mixing of fuel and air is promoted. Therefore, even if the amount of fuel is small, the combustion is performed well.

  Further, when the engine operating state is in the low rotation region Z1 shown in FIG. 6 and the internal combustion engine is performing full load combustion, as shown in FIG. The intake passage 5 is closed so that the tumble control valve 17 closes one of the divided intake passages 12. That is, when the internal combustion engine performs full load combustion, it is necessary to increase the intake amount as much as possible. Here, when the engine operating state is in the low rotation region Z1, the intake passage is as long as possible in the shape of the intake passage (the shape of the intake passage through which air flows from the surge tank 1 to the combustion chamber 4). If the shape is small, an inertial supercharging effect can be obtained, and the intake air amount becomes very large. Therefore, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage is the longest intake passage and the sectional area of the passage is small. A large amount of air can flow into the combustion chamber 4.

  When the internal combustion engine is in the low / medium speed region Z2 shown in FIG. 6 and the internal combustion engine is performing full load combustion, as shown in FIG. The intake passage 5 is closed so that the tumble control valve 17 opens the divided intake passage 12. That is, when the internal combustion engine performs full load combustion, it is necessary to increase the intake amount as much as possible. Here, when the engine operating state is in the low / medium rotation region Z2, if the shape of the intake passage is the second longest intake passage and the cross-sectional area is small, the inertia supercharging effect can be obtained and the intake air amount is extremely low. To be more. Therefore, as described above, when the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage is the second longest intake passage and the sectional area of the passage is small. A very large amount of air can flow into the combustion chamber 4.

  Further, when the engine operating state is in the middle / high rotation region Z3 shown in FIG. 6 and the internal combustion engine is performing full load combustion, as shown in FIG. The intake passage 5 is opened so that the tumble control valve 17 closes one of the divided intake passages 12. That is, when the internal combustion engine performs full load combustion, it is necessary to increase the intake amount as much as possible. Here, when the engine operating state is in the middle / high rotation range Z3, if the shape of the intake passage is the third longest intake passage and the sectional area of the passage is small from the relationship with the engine speed, the inertia supercharging effect is obtained. Is obtained and the amount of air is very large. Therefore, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage is the third longest intake passage and the smaller cross-sectional area. A very large amount of air can flow into the combustion chamber 4.

  Further, when the engine operating state is in the high rotation region Z4 shown in FIG. 6 and the internal combustion engine is performing full load combustion, as shown in FIG. The intake passage 5 is opened so that the tumble control valve 17 opens the divided intake passage 12. That is, when the internal combustion engine performs full load combustion, it is necessary to increase the intake amount as much as possible. Here, when the engine operating state is in the high rotation region Z4, if the shape of the intake passage is made as short as possible and the cross-sectional area of the passage is large from the relationship with the engine speed, the inertia supercharging effect can be obtained. As a result, the intake air amount becomes very large. Therefore, as described above, if the intake passage length changing valve 11 and the tumble control valve 17 are controlled, the shape of the intake passage becomes the shape with the shortest intake passage and the largest passage cross-sectional area. A large amount of air can flow into the combustion chamber 4.

  When the main intake passage 5, the sub intake passage 8, the intake passage length change valve 11, and the tumble control valve 17 are configured and arranged as in this embodiment, the intake passage from the surge tank 1 to the combustion chamber 4 is arranged. Therefore, there is no or almost no region where the volume changes greatly, so that a higher inertial supercharging effect can be obtained. In particular, in the third embodiment, a region W1 in which the volume of the intake passage that changes when the intake passage length change valve 11 and the tumble control valve 17 are in the state shown in FIG. Since it does not occur as shown in FIG. 11, a higher inertial supercharging effect can be obtained.

  Further, according to the present embodiment, when one divided intake passage 12 is closed by the tumble control valve 17, a stronger tumble flow of air (air mixture) is formed in the combustion chamber 4. That is, for example, when the tumble control valve 17 is attached to an intermediate portion of the partition wall 14 as in the second embodiment shown in FIGS. 7 to 10, as can be seen with reference to FIG. When one of the divided intake passages 12 is closed by 17, the space W2 of the divided intake passage 12 downstream of the tumble control valve 17 is relatively large, and the division of the downstream of the tumble control valve 17 is performed while the intake valve 19 is closed. Air accumulates in the intake passage 12. In this case, when the intake valve 19 is opened and air is sucked into the combustion chamber 4, the air accumulated in the space W 2 of the divided intake passage 12 downstream of the tumble control valve 17 is also sucked into the combustion chamber 4. Therefore, the tumble flow of air (air mixture) formed in the combustion chamber 4 may be weakened. However, as in the third embodiment, when the tumble control valve 17 is attached to a portion adjacent to the end of the partition wall 14 on the combustion chamber 4 side, as can be seen with reference to FIG. When one of the divided intake passages 12 is closed, the space of the divided intake passage 12 downstream of the tumble control valve 17 is relatively small, and the divided intake passage downstream of the tumble control valve 17 is closed while the intake valve 19 is closed. The amount of air accumulated in 12 is very small. For this reason, when the intake valve 19 is opened and air is sucked into the combustion chamber 4, very little air is sucked into the combustion chamber 4 from the space of the divided intake passage 12 downstream of the tumble control valve 17. The amount of air sucked into the combustion chamber 4 through the divided intake passage 13 not closed by the valve 17 is overwhelmingly larger. Therefore, a stronger tumble flow of air (air mixture) is formed in the combustion chamber 4.

  In the first embodiment, when the intake passage length changing valve 11 and the tumble control valve 17 are switched from the state shown in FIG. 2 to the state shown in FIG. 3, the intake passage length changing valve 11 and the tumble control are switched. The valve 17 may be simultaneously switched from the state shown in FIG. 2 to the state shown in FIG. 3, but when the states of the intake passage length changing valve 11 and the tumble control valve 17 are switched, the internal combustion engine From the viewpoint of minimizing at least the fluctuation that will occur in the torque output from the engine, first, the intake passage length changing valve 11 is changed from the state shown in FIG. 2 to the state shown in FIG. After switching, it is preferable to switch the tumble control valve 17 from the state shown in FIG. 2 to the state shown in FIG. That is, it is preferable to switch the intake passage length changing valve 11 and the tumble control valve 17 from the state shown in FIG. 2 to the state shown in FIG. 3 via the state shown in FIG.

  For the same reason, in the second embodiment, when the intake passage length changing valve 11 and the tumble control valve 17 are switched from the state shown in FIG. 8 to the state shown in FIG. 11 and the tumble control valve 17 are preferably switched from the state shown in FIG. 8 to the state shown in FIG. 9 via the state shown in FIG. For the same reason, when the intake passage length changing valve 11 and the tumble control valve 17 are switched from the state shown in FIG. 12 to the state shown in FIG. It is preferable to switch the change valve 11 and the tumble control valve 17 from the state shown in FIG. 12 to the state shown in FIG. 13 via the state shown in FIG.

  Further, in the first embodiment, when the intake passage length changing valve 11 and the tumble control valve 17 are switched from the state shown in FIG. 3 to the state shown in FIG. The tumble control valve 17 may be simultaneously switched from the state shown in FIG. 3 to the state shown in FIG. 2, but when the states of the intake passage length changing valve 11 and the tumble control valve 17 are switched. From the viewpoint of minimizing fluctuations that may occur in the torque output from the internal combustion engine, first, the tumble control valve 17 is switched from the state shown in FIG. 3 to the state shown in FIG. It is preferable to switch the intake passage length changing valve 11 from the state shown in FIG. 3 to the state shown in FIG. 2 later. That is, it is preferable to switch the intake passage length changing valve 11 and the tumble control valve 17 from the state shown in FIG. 3 to the state shown in FIG. 2 via the state shown in FIG.

  For the same reason, in the second embodiment, when the intake passage length changing valve 11 and the tumble control valve 17 are switched from the state shown in FIG. 9 to the state shown in FIG. 11 and the tumble control valve 17 are preferably switched from the state shown in FIG. 9 to the state shown in FIG. 8 via the state shown in FIG. For the same reason, when the intake passage length changing valve 11 and the tumble control valve 17 are switched from the state shown in FIG. 13 to the state shown in FIG. The change valve 11 and the tumble control valve 17 are preferably switched from the state shown in FIG. 13 to the state shown in FIG. 12 via the state shown in FIG.

FIG. 3 is a view showing an intake control device for an internal combustion engine according to the first embodiment of the present invention in a state in which an intake passage length change valve closes a main intake passage and a tumble control valve closes one divided intake passage. . FIG. 2 is a view showing the internal combustion engine intake control device according to the first embodiment of the present invention, as in FIG. 1, but here the intake passage length change valve closes the main intake passage and the tumble control valve is divided intake air The passage is open. FIG. 2 is a view showing the internal combustion engine intake control device according to the first embodiment of the present invention, as in FIG. 1, but here the intake passage length change valve opens the main intake passage and the tumble control valve The split intake passage is closed. FIG. 2 is a view showing the internal combustion engine intake control apparatus according to the first embodiment of the present invention, as in FIG. 1, but here the intake passage length changing valve opens the main intake passage and the tumble control valve is divided intake air The passage is open. It is a figure for demonstrating the tumble flow of the air (air mixture) formed in a combustion chamber. FIG. 4 is a diagram showing an engine operating state divided into a plurality of regions according to an engine speed N and an engine load L. FIG. 6 is a diagram showing an intake control device for an internal combustion engine according to a second embodiment of the present invention in a state where an intake passage length change valve closes a main intake passage and a tumble control valve closes one divided intake passage. . FIG. 8 is a diagram showing an intake control device for an internal combustion engine according to a second embodiment of the present invention, similar to FIG. 7, but here, the intake passage length change valve closes the main intake passage and the tumble control valve is divided intake The passage is open. FIG. 9 is a view showing an intake control device for an internal combustion engine according to a second embodiment of the present invention, similar to FIG. 7, but here, the intake passage length changing valve opens the main intake passage and the tumble control valve is one of the control valves. The split intake passage is closed. FIG. 8 is a diagram showing an intake control device for an internal combustion engine according to a second embodiment of the present invention, similar to FIG. 7, but here the intake passage length changing valve opens the main intake passage and the tumble control valve is divided intake The passage is open. FIG. 6 is a view showing an intake control device for an internal combustion engine according to a third embodiment of the present invention in a state where an intake passage length change valve closes a main intake passage and a tumble control valve closes one divided intake passage. . FIG. 12 is a diagram showing an intake control device for an internal combustion engine according to a third embodiment of the present invention, similar to FIG. 11, but here, the intake passage length changing valve closes the main intake passage and the tumble control valve is divided intake air The passage is open. 11 is a view showing an intake control device for an internal combustion engine according to a third embodiment of the present invention, similar to FIG. 11, in which the intake passage length changing valve opens the main intake passage and the tumble control valve is one of the tumble control valves. The split intake passage is closed. FIG. 12 is a view showing an intake control device for an internal combustion engine according to a third embodiment of the present invention, as in FIG. 11, but here the intake passage length changing valve opens the main intake passage and the tumble control valve is divided intake air The passage is open.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surge tank 3 Main intake pipe 4 Combustion chamber 5 Main intake passage 6 Sub intake pipe 8 Sub intake passage 9, 15 Rotating shaft 10, 10A, 10B, 16 Plate-shaped valve body 11 Intake passage length change valve 12, 13 Division Intake passage 17 Tumble control valve

Claims (9)

A surge tank; a first intake passage extending from the surge tank and connected to the combustion chamber; a second intake passage extending from the surge tank and connected to the first intake passage; and the second intake passage. And an intake passage length changing valve that closes or opens the first intake passage upstream of a connection location between the first intake passage and the first intake passage, and a connection location between the second intake passage and the first intake passage. A partition disposed in the first intake passage so as to divide the internal space of the first intake passage on the downstream side into two along the axis of the first intake passage to form two divided intake passages; A tumble control valve that closes or opens one of the divided intake passages, and flows into the combustion chamber via the other divided intake passage when one of the divided intake passages is closed by the tumble control valve. So as to form a tumble flow In the intake control device for an internal combustion engine in which the partition wall is disposed in the first intake passage, the length of the second intake passage from the surge tank to the first intake passage is the length from the surge tank to the second intake passage. The first intake air from the surge tank to the connection portion between the second intake passage and the first intake passage is longer than the length to the connection portion with the first intake passage. smaller than the passage sectional area of the passage, the tumble control valve is attached, et al is the partition wall so as to rotate about the rotation shaft attached to said partition wall,
When the tumble control valve has a plate-like valve body that can turn around the turning shaft, and the tumble control valve opens one of the divided intake passages, the plate-like valve of the tumble control valve The body is parallel to the partition,
The second intake passage is connected to the first intake passage from a direction substantially perpendicular to the partition, and the tumble control valve is connected to the first intake passage with respect to the partition. The split intake passage formed on the side opposite to the closed side is closed or opened, the rotating shaft of the tumble control valve is attached to the combustion chamber side end of the partition wall, and the tumble control valve is connected to the split intake passage The plate-shaped valve body of the tumble control valve is on the same plane or substantially the same plane as the partition wall,
An intake air control apparatus for an internal combustion engine.   The intake control device for an internal combustion engine according to claim 1, wherein the second intake passage is connected to a portion of the first intake passage closer to the surge tank than the combustion chamber.   The intake control apparatus for an internal combustion engine according to claim 2, wherein the second intake passage is connected to a portion of the first intake passage adjacent to the surge tank. When the intake passage length change valve has a plate-like valve body, and the intake passage length change valve opens the first intake passage, the plate-like valve body of the intake passage length change valve is the same as the partition wall The intake control device for an internal combustion engine according to any one of claims 1 to 3, wherein the intake control device is on a plane or substantially on the same plane. When the intake passage length changing valve is opening the first intake passage, the combustion chamber side peripheral portion of the plate-like valve body of the intake passage length changing valve is adjacent to the surge tank side end portion of the partition wall. 5. The intake control device for an internal combustion engine according to claim 4, wherein The intake passage length change valve has two plate-like valve bodies that can rotate independently in different regions around a rotation axis adjacent to each other or around a common rotation axis. When the passage length changing valve opens the first intake passage, the peripheral portion of one plate-like valve body of the intake passage length changing valve is adjacent to the surge tank side end of the partition wall and the intake passage length 6. The internal combustion engine according to claim 5, wherein a peripheral portion of the other plate-shaped valve body of the change valve is adjacent to a surge tank side end surface portion of the second intake passage connected to the first intake passage. Intake control device. When air is sucked into the combustion chamber via the first intake passage when the engine speed is higher than a predetermined engine speed, air is sucked into the combustion chamber with the help of the inertia supercharging effect. At the same time, when the engine speed is lower than the predetermined engine speed, if air is sucked into the combustion chamber via the second intake passage, the inertia supercharging effect is obtained and the air enters the combustion chamber. The length and passage cross-sectional area of the first intake passage and the length and passage cross-sectional area of the second intake passage are set so as to be inhaled. Intake control device for internal combustion engine. When the engine load is lower than a predetermined engine load in an engine load region where the internal combustion engine is smaller than the full load or a load near the full load, the air-fuel ratio of the mixture in the combustion chamber is set to an air-fuel ratio larger than the stoichiometric air-fuel ratio. Lean burn combustion is performed to cause combustion, and when the engine load is higher than the predetermined engine load in the engine load region where the internal combustion engine is smaller than the full load or a load near the full load, When the stoichiometric combustion is performed with the air-fuel ratio being the stoichiometric or substantially stoichiometric air-fuel ratio and the internal combustion engine is performing stoichiometric combustion, the intake passage length changing valve opens the first intake passage. When the tumble control valve opens the split intake passage and the internal combustion engine is performing lean burn combustion, the intake passage length change valve opens the first intake passage. In addition, when the tumble control valve closes one of the divided intake passages and the engine load is a full load or a load close to the full load, the operation of the intake passage length changing valve and the operation of the tumble control valve according to the engine speed Is controlled, the intake control device for an internal combustion engine according to any one of claims 1 to 7. When the operating state of the internal combustion engine is divided into a low rotation operation state, a low / medium rotation operation state, a medium / high rotation operation state, and a high rotation operation state in order of increasing engine speed, the engine load is a full load or a load near the full load. When the internal combustion engine is operating at a low speed, the intake passage length change valve closes the first intake passage and the tumble control valve closes one of the divided intake passages. When the engine is at full load or near full load and the internal combustion engine is in the low / medium speed operation state, the intake passage length changing valve closes the first intake passage and the tumble control valve opens the divided intake passage. When the engine load is a full load or a load near the full load and the operating state of the internal combustion engine is in the middle / high rotation operation state, the intake passage length change valve opens the first intake passage and When the control valve closes one of the divided intake passages, the engine load is at or near the full load, and the operation state of the internal combustion engine is in the high rotation operation state, the intake passage length change valve is the first intake air intake valve. 9. The intake control apparatus for an internal combustion engine according to claim 8, wherein the passage is opened and the tumble control valve is opened in a divided intake passage.

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