JP4349156B2 - Intake device for internal combustion engine - Google Patents

Description

  The present invention relates to an intake device for supplying air to a main body of an internal combustion engine.

  In an internal combustion engine, for example, an automobile engine, it is required to form a lean air-fuel mixture in order to reduce fuel consumption at low loads, for example, during a period from engine start to first idle. Especially when the EGR system is designed to reduce nitrogen oxide (NOx) by reducing the combustion temperature by recirculating a part of the exhaust gas together with the intake gas to the combustion chamber. There may be cases where a sufficient amount of recirculated exhaust gas cannot be secured. In such a case, a vortex in the cylinder of the internal combustion engine, for example, a vertical vortex (tumble) flowing in the axial direction of the cylinder and / or a horizontal vortex (swirl) flowing in the circumferential direction of the cylinder is generated, thereby causing misfire. The lean mixture is burned without any problems.

  FIG. 10A is a diagram showing a relationship between a crank angle (horizontal axis) and an intake valve lift amount (vertical axis) in a general internal combustion engine, and FIG. 10B is an intake valve in a general internal combustion engine. It is a figure which shows the relationship between lift amount (horizontal axis) and tumble strength (vertical axis). As shown in FIG. 10A, when the maximum lift amount of the intake valve is lowered from the lift amount A that is a relatively large value to the lift amount B that is a relatively small value, the tumble strength is as shown in FIG. Decline as shown. That is, as shown in FIG. 10B, the smaller the lift amount, the lower the tumble strength.

  This will be described with reference to FIG. 11 (a) and 11 (b) are longitudinal sectional views of an intake device for an internal combustion engine in the prior art. FIG. 11 (a) shows a case where the lift amount of the intake valve is relatively small, and FIG. This shows a case where the lift amount of the intake valve is relatively large. Since the intake port 11 is inclined with respect to the cylinder 8 of the internal combustion engine, when the lift amount is relatively large as shown in FIG. A large amount flows into the cylinder 8 from the side close to the exhaust valve 4. That is, in this case, since the directivity of air is high, the tumble T is generated as illustrated. On the other hand, as shown in FIG. 11A, when the lift amount is relatively small, air flows into the cylinder 8 almost uniformly from the entire periphery of the valve body of the intake valve 3, so that the air The directivity is reduced and the tumble T is also reduced. In such a case, the atomization of the fuel can be promoted because the flow velocity of the air passing through the intake valve is increased, but the tumble strength is reduced as shown in FIG. For example, rapid combustion cannot be performed, and combustion stability cannot be ensured.

Various attempts have been made to generate a tumble flow when desired. For example, in Patent Document 1, an upper flow path and a lower flow path are formed in the intake port by providing partition means for partitioning the interior of the intake port in the vertical direction. When it is desired to generate a tumble flow, the upper flow path is opened and the lower flow path is closed by an opening / closing means, whereby air is allowed to flow only in the upper flow path to generate a tumble flow. Further, in Patent Document 2, a tumble intake port for generating a tumble flow in addition to a normal intake port is separately provided. For example, when the load is low, the tumble intake port, which is normally closed, is opened to generate tumble. Further, in Patent Document 3, by providing a recess on the inner surface of the combustion chamber near the periphery farthest from the exhaust port, the clearance between the intake valve periphery and the combustion chamber surface during intake valve lift is changed by a predetermined amount. In this state, a tumble flow is generated (see Patent Document 1 to Patent Document 3).
JP 2001-3755 A JP 7-42408 A Japanese Patent Laid-Open No. 5-118222

  Here, it is assumed that partition means for forming the upper flow path and the lower flow path is provided in the internal combustion engine shown in FIGS. 11A and 11B as described in Patent Document 1. When the intake valve lift amount is relatively large (see FIG. 11B), the clearance between the intake valve 3 and the opening of the intake port 11 is relatively large. The air flowing through the air flows into the cylinder 8 through this gap and tends to cause tumble. However, when the intake valve lift amount is relatively small (see FIG. 11A), the air flowing through the upper flow path collides with the bent portion W near the exhaust port 2 of the intake ports. As a result, the flow velocity tends to decrease, so that air does not flow smoothly into the cylinder 8, and therefore tumble is less likely to occur. For this reason, it is desirable that tumble be generated particularly when the lift amount of the intake valve 3 is relatively small.

  Furthermore, providing a tumble intake port as described in Patent Document 2 and forming a recess in the combustion chamber as described in Patent Document 3 require that the cylinder block itself of the internal combustion engine be remanufactured. Because there is a large amount of money is required, it is not realistic.

  The present invention has been made in view of such circumstances, and an intake air that can form a tumble in a combustion chamber of an internal combustion engine by a simple and inexpensive method even when the lift amount of the intake valve is relatively small. An object is to provide an apparatus.

In order to achieve the above-described object, according to the first aspect of the invention, at least one intake port that opens to the combustion chamber of the internal combustion engine and an intake valve that opens and closes the intake port are lifted and lowered. A movable valve mechanism for adjusting the flow rate, a secondary flow path forming means for forming a secondary flow path extending in parallel with the intake port in the intake port, and a secondary flow path provided upstream of the secondary flow path. An intake adjustment valve that opens and closes to flow air through the passage, and the sub-flow passage is formed on a lower side of the transverse section in the transverse section of the entire at least one intake port, and is formed by the movable valve mechanism section. An intake device is provided in which when the maximum lift amount of the intake valve to be adjusted is smaller than a predetermined value, the intake adjustment valve allows air to flow only through the auxiliary flow path.

  That is, in the first aspect of the invention, the air passing through the sub-flow path flows into the combustion chamber from the exhaust port side of the peripheral edge of the intake valve along the upper surface of the intake valve. The amount of air flowing in from the exhaust port side is considerably larger than the amount of air flowing in from the periphery of the intake valve on the side opposite to the exhaust port. As a result, in the first aspect, it is possible to form a tumble in the combustion chamber of the internal combustion engine even when the lift amount of the intake valve is relatively small.

According to a second aspect, in the first aspect, the sub-flow path is formed near the center of the cross section in the cross section of the entire at least one intake port.
That is, in the second aspect of the invention, when the sub-flow path is formed near the center of the intake port, the amount of air flowing into the cylinder from the lateral side of the peripheral edge of the intake valve is reduced. The amount of air that flows into the combustion chamber from the exhaust port side is further increased than the amount of air that flows from the periphery of the intake valve on the side opposite to the exhaust port, and the tumble that occurs when the lift amount of the intake valve is relatively small The strength can be further increased.

According to a third aspect, in the first or second aspect, the number of the intake ports is one, and the sub-flow passage forming means is arranged on the intake line from an axis in the intake port parallel to the intake port. Two plate-like bodies extending so as to form a predetermined angle to the inner wall of the port, and the sub-flow channel is formed between the plate-like bodies forming the predetermined angle.
That is, according to the third aspect of the present invention, when the lift amount of the intake valve is relatively small, the internal combustion engine can be operated in a simple and inexpensive manner by arranging two plate-like bodies forming the sub-flow passages inside one intake port. A tumble can be formed in the combustion chamber. The two plate-like bodies do not need to extend from the center line of the intake port, and the two plate-like bodies do not need to be arranged symmetrically with respect to the vertical plane.

According to a fourth invention, in the first or second invention, there is one intake port, and the auxiliary flow path forming means is a tubular member arranged in the intake port.
That is, according to the fourth aspect of the present invention, when a lift amount of the intake valve is relatively small, the tubular member forming the sub-flow path is disposed inside one intake port. A tumble can be formed.

According to a fifth aspect, in the first or second aspect, the intake ports are first and second intake ports parallel to each other, and the sub-flow passage forming means in the first intake port is A first partition means for partitioning the interior of the first intake port, and the sub-flow passage forming means in the second intake port is a second partition means for partitioning the interior of the second intake port; Each of the partitioning means and the second partitioning means are disposed so as to incline downward from the center plane between the first intake port and the second intake port.
That is, in the fifth aspect of the invention, the partitioning means for forming the first and second sub-flow passages are arranged inside the first and second intake ports, respectively, and these sub-flow passages are arranged close to each other. By a simple and inexpensive method, the tumble can be formed in the combustion chamber of the internal combustion engine when the lift amount of the intake valve is relatively small. The partition means does not have to pass through the center line of each intake port.

According to a sixth invention, in the first or second invention, the intake ports are first and second intake ports parallel to each other, and the sub-flow passage forming means in the first intake port is Two plate-like bodies each extending from an axis in the first intake port parallel to the first intake port to an inner wall of the first intake port so as to form a predetermined angle with each other. A flow path is formed between the plate-like bodies forming the predetermined angle, and the secondary flow path forming means in the second intake port is the second flow path parallel to the second intake port. Two plate-like bodies each extending from the axis in the intake port to the inner wall of the second intake port so as to form a predetermined angle with each other, and a second sub-flow passage of the plate-like bodies having the predetermined angle. Formed between the first sub-flow path and the first sub-flow path. The second intake passage is disposed below and on the second intake port side, and the second sub-flow channel is disposed on the first intake port side and below the second intake port. Has been.
That is, in the sixth aspect of the invention, the two plate-like bodies that respectively form the first and second sub-channels are disposed inside the first and second intake ports, respectively, and these sub-channels are close to each other. By the simple and inexpensive method of arranging in such a manner, the tumble can be formed in the combustion chamber of the internal combustion engine when the lift amount of the intake valve is relatively small. The two plate-like bodies do not need to extend from the center line of the intake port, and the two plate-like bodies do not need to be arranged symmetrically with respect to the vertical plane.

According to a seventh aspect, in the first or second aspect, the intake ports are first and second intake ports parallel to each other, and the sub-flow passage forming means in the first intake port is A first tubular member disposed on the lower side and on the second intake port side in the first intake port, wherein the sub-flow passage forming means in the second intake port is the second intake port It is the 2nd tubular member arrange | positioned in said 1st intake port side and the downward side.
That is, in the seventh invention, the tubular members forming the first and second sub-flow paths are respectively arranged inside the first and second intake ports, and the sub-flow paths are arranged close to each other. By this simple and inexpensive method, the tumble can be formed in the combustion chamber of the internal combustion engine when the lift amount of the intake valve is relatively small.

  According to each invention, even if the lift amount of the intake valve is relatively small, it is possible to achieve a common effect that a tumble can be formed in the combustion chamber of the internal combustion engine.

Furthermore, according to the second aspect of the invention, the effect that the tumble strength can be further increased can be achieved.
Furthermore, according to the third aspect of the invention, a simple and inexpensive method of arranging the two plate-like bodies forming the sub-flow passages inside one intake port allows the tumble when the lift amount of the intake valve is relatively small. The effect that can be formed can be produced.
Further, according to the fourth invention, the tumble is formed when the lift amount of the intake valve is relatively small by a simple and inexpensive method of arranging the tubular member forming the sub-flow channel inside one intake port. The effect that it is possible can be produced.
Further, according to the fifth aspect of the present invention, the partition means for forming the first and second sub flow paths are respectively arranged in the first and second intake ports, and the sub flow paths are arranged close to each other. By the simple and inexpensive method of arranging the tumble, the tumble can be formed when the lift amount of the intake valve is relatively small.
Further, according to the sixth aspect, the two plate-like bodies that respectively form the first and second sub-flow passages are disposed inside the first and second intake ports, respectively, and these sub-flow passages are mutually connected. By a simple and inexpensive method of arranging them close to each other, it is possible to produce an effect that a tumble can be formed when the lift amount of the intake valve is relatively small.
Further, according to the seventh aspect, the tubular members forming the first and second sub-flow passages are disposed inside the first and second intake ports, respectively, and these sub-flow passages are arranged close to each other. The simple and inexpensive method of disposing can produce an effect that a tumble can be formed when the lift amount of the intake valve is relatively small.

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the following drawings, the same members are denoted by the same reference numerals. In order to facilitate understanding, the scales of these drawings are appropriately changed.
FIG. 1 is a longitudinal sectional view of a direct injection spark ignition internal combustion engine equipped with an intake device according to the present invention. In the figure, 11 is an intake port and 2 is an exhaust port. The intake port 11 communicates with the cylinder via the intake valve 3 and the exhaust port 2 communicates with the cylinder via the exhaust valve 4. 5 is a piston, 6 is a spark plug disposed substantially at the center of the upper part of the cylinder, 7 is a fuel injection valve for directly injecting fuel from the periphery of the upper part of the cylinder into the cylinder, and 8 is a cylinder of the internal combustion engine. is there. In order to prevent fuel vapor, the fuel injection valve 7 is disposed downstream of an intake control valve 31 (to be described later) on the intake port 11 side where the temperature of the combustion chamber becomes relatively low due to the intake air flow. Although the other intake port 12 described later is not shown in FIG. 1, the intake port 12 also includes an intake valve similar to the intake port 11. These intake valve and exhaust valve 4 are moved up and down by a movable valve mechanism (not shown) to open and close the intake ports 11 and 12 and the exhaust port 2, respectively.

  As shown in FIG. 1, the general intake port 11 extends obliquely upward from the upper part of the cylinder to the anti-exhaust valve side. In FIG. 1 and the like, it is assumed that the cross section of the intake port 11 is circular, but the cross section of the intake port 11 may be other shapes such as a rectangle. In FIG. 1, a sub flow channel forming portion 38 capable of forming a sub flow channel in the intake port 11 is provided. As shown in FIG. 1, the auxiliary flow path forming portion 38 extends substantially parallel to the intake port 11 over a predetermined length. Further, the adjustment valve 31 is provided on the upstream side of the sub flow path forming portion 38. The fuel injection valve 7 described above is provided downstream of the sub-flow passage forming portion 38, thereby preventing the fuel from adhering to the sub-flow passage forming portion 38 and mixing the fuel and air well. I'm trying to let you.

  FIG. 2A is a cross-sectional view taken along line II of FIG. 1 for explaining the intake device according to the first embodiment of the present invention. Note that the intake port 11 portion of FIG. 1 shows a cross section taken along line II-II of FIG. 2, in addition to the intake port 11 shown in FIG. 1, another intake port 12 arranged in parallel and close to the intake port 11 is shown, and an intake valve (not shown) in the intake port 12 is shown. Is moved up and down by the same movable valve mechanism as the intake valve 3 in the intake port 11. As shown in FIG. 2A, the auxiliary flow path forming portion 38 disposed in the intake port 11 extends in the diameter direction in the cross section of the intake port 11, and both edge portions of the auxiliary flow passage forming portion 38 are It abuts against the inner wall of the intake port 11. Similarly, the auxiliary flow path forming portion 39 disposed in the intake port 12 also extends in the diameter direction in the cross section of the intake port 12, and both edges of the auxiliary flow path forming portion 39 abut against the inner wall of the intake port 12. ing. The sub-flow channel forming portion 38 in the intake port 11 has a predetermined angle downward with respect to the center plane (in this case, the vertical plane) between the intake port 11 and the intake port 12, and in FIG. It arrange | positions so that the angle of 45 degrees may be made. For this reason, the inside of the intake port 11 is divided into two flow paths by the sub flow path forming portion 38, and the flow path positioned below one of these is hereinafter referred to as “sub flow path”. . As shown in the drawing, a sub flow channel 21 is formed in the intake port 11 by a sub flow channel forming portion 38. On the other hand, the sub-flow channel forming portion 39 in the intake port 12 is similarly below the center plane between the intake port 11 and the intake port 12 so as to face the sub-flow channel forming portion 38 in the intake port 11. Are arranged at a predetermined angle, for example, an angle of about 45 °. The sub flow path 22 is similarly formed in the intake port 12 by the sub flow path forming portion 39.

  Further, in FIG. 2A, the regulating valve 31 disposed upstream of the sub flow path forming portion 38 has a sector shape of about 180 °, that is, a half moon shape. The adjustment valve 31 rotates about the axis A along the sub-flow passage forming portion 38 between a direction parallel to the axis of the intake port 11 and a direction perpendicular to the axis of the intake port 11. It can be done. As shown in FIG. 2A, when the adjustment valve 31 is rotated perpendicularly to the axis of the intake port 11, the portion other than the sub flow path 21 in the intake port 11 is closed. The adjustment valve 32 provided upstream of the auxiliary flow path forming portion 39 in the intake port 12 has the same configuration as the adjustment valve 31, and the adjustment valve 32 closes the portion other than the auxiliary flow path 22 in the intake port 12. Thus, it can be rotated around the axis B. As shown in FIG. 2A, the auxiliary flow paths 21 and 22 are disposed near the center and on the lower side in the cross section of the entire intake ports 11 and 12.

  In the first embodiment shown in FIG. 2A, when the lift amount of the intake valve 3, that is, the rising distance is large, the adjustment valves 31 and 32 are rotated in parallel with the intake ports 11 and 12. As a result, the air flows through the intake ports 11 and 12 as a whole. Therefore, as described with reference to FIG. 10B, the air flows from the side close to the exhaust valve 4 in the peripheral edge of the valve body of the intake valve 3. A large amount enters the cylinder 8 and a tumble T is generated in the cylinder 8.

  On the other hand, when the lift amount of the intake valve 3 is relatively small, for example, smaller than a predetermined lift amount, the adjustment valve 31 and the adjustment valve 32 are closed. Thus, as shown in the longitudinal sectional view of the internal combustion engine in FIG. 3A and the horizontal sectional view of the internal combustion engine in FIG. As can be seen from these drawings, the sub-flow passages 21 and 22 are arranged near the center and on the lower side in the entire cross section of the intake ports 11 and 12. The heading speed component is given. As can be seen with reference to FIG. 3 (a), the intake air to which this speed component is applied flows along the upper surface of the intake valve 3, and the intake openings 3, 12 are connected to the openings in the cylinders of the intake ports 11 and 12. Pass through the gaps between them. At this time, the intake air supplied into the cylinder via the exhaust valve side at the opening in the cylinder of the intake ports 11 and 12 is not deflected so much that the speed does not decrease so much. The amount of air flowing in from the port 2 side is considerably larger than the amount of air flowing in from the periphery of the intake valve 3 on the side opposite to the exhaust port 2. Then, this air moves toward the exhaust valve side of the cylinder at a relatively high speed, and descends the exhaust valve side of the cylinder through the top surface of the piston as shown by the solid line arrow in FIG. 1 and FIG. A strong (high strength) tumble T that rises on the intake valve side of the cylinder is formed. Further, as shown in FIG. 3B, air flows in the vicinity of the center between the intake port 11 and the intake port 12, so that the amount of air flowing into the cylinder from the peripheral side of the intake valve decreases. As a result, the tumble T having higher strength is formed.

  FIG. 4 is a diagram showing the relationship between the lift amount (valve lift amount) of the intake valve and the tumble strength in the internal combustion engine equipped with the intake device according to the present invention. In FIG. 4, the horizontal axis indicates the lift amount of the intake valve, and the vertical axis indicates the tumble strength. In FIG. 4, a solid line Z1 indicates the case of the internal combustion engine in the prior art, and a solid line Z2 indicates the case of the internal combustion engine in which measures are taken to generate the tumble flow as described in Patent Documents 1 to 3 described above. Show. Compared to the case of the solid line Z1 in which no countermeasures are taken with respect to the tumble flow, the tumble strength is large in both the relatively large lift amount B and the relatively small lift amount A in the case of the solid line Z2.

  On the other hand, the dotted line Z3 in FIG. 4 shows the relationship between the lift amount and the tumble strength when air is allowed to flow only through the auxiliary flow passages 21 and 22 in the internal combustion engine equipped with the intake device according to the present invention. As shown in the figure, in the case of the dotted line Z3, when the lift amount is relatively small, for example, in the case of the lift amount A, a larger tumble strength is obtained than in the case of the prior art (solid line Z1 and solid line Z2). . However, as shown in the figure, when the lift amount exceeds the X coordinate C of the intersection between the solid line Z2 and the dotted line Z3, the tumble strength becomes smaller than the solid line Z2 in the case of the prior art. For this reason, when the lift amount is smaller than a predetermined value, for example, the lift amount C shown in FIG. 4, air is allowed to flow only through the sub-flow channels 21 and 22, and the lift amount exceeds a predetermined value. It is preferable that the regulating valves 31 and 32 are opened to allow air to flow through the entire intake ports 11 and 12. In such a case, in the internal combustion engine provided with the intake device of the present invention, even if the lift amount of the intake valve is relatively small and the lift amount is relatively large, the tumble strength is relatively low. Can be kept high.

  Although the auxiliary flow path forming portions 38 and 39 arranged in the diameter direction in the intake device of the present invention have been described with reference to FIG. 2A, the auxiliary flow passage forming portions 38 and 39 are not necessarily connected to the intake ports 11 and 12. It is not necessary to pass through the respective centers, and the valves may be arranged at positions shifted from the centers of the intake ports 11 and 12, and the regulating valves 31 and 32 may have shapes corresponding thereto.

  Further, the shapes of the auxiliary flow path forming portions 38 and 39 and the regulating valves 31 and 32 in the intake device of the present invention may be other shapes than those shown in FIG. FIG. 2B is a cross-sectional view taken along the line II of FIG. 1 for explaining the intake device according to the second embodiment of the present invention. In FIG. 2B, the auxiliary flow path forming portion 38 disposed in the intake port 11 is composed of two plate-like members 38A and 38B that form a predetermined angle with each other. As shown in the figure, the plate-like members 38A and 38B extend from the center of the intake port 11 to the inner wall of the intake port 11 perpendicularly to each other, and the sub-flow channel 21 is formed between the plate-like members 38A and 38B. ing. Similarly, in the intake port 12, two plate-like members 39A and 39B extending from the center of the intake port 12 to the inner wall of the intake port 12 perpendicularly to each other are provided. As shown in the figure, both the plate-like member 38A in the intake port 11 and the plate-like member 39A in the intake port 12 face the vertical direction. The plate member 38B in the intake port 11 and the plate member 39B in the intake port 12 are disposed adjacent to each other. That is, the auxiliary flow path 21 in the intake port 11 is arranged on the intake port 12 side and the lower side, and the auxiliary flow path 22 in the intake port 12 is arranged on the intake port 11 side and the lower side. Therefore, as shown in FIG. 2B, the auxiliary flow passages 21 and 22 are arranged near the center and on the lower side in the cross section of the entire intake ports 11 and 12. In FIG. 2B, the plate-like members 38A and 39A are arranged in the vertical direction. However, the plate-like members 38A and 39A are arranged so as to be shifted from the vertical direction, and the center in the intake ports 11 and 12 is set. Two plate-like members may extend from other positions. Further, even if the sub-channel 21 and the sub-channel 22 are not formed symmetrically, the sub-channels 21 and 22 are located near the center and / or on the lower side in the entire cross section of the intake ports 11 and 12. Are included in the scope of the present invention.

  Further, in FIG. 2B, the regulating valve 31 disposed upstream of the auxiliary flow path forming portions 38A and 38B is also composed of two regulating valves 31A and 31B. As shown in the drawing, the two axes A1 and B1 extend so as to form an equal angle with respect to the plate member 38A and the plate member 38B, respectively, and the adjustment valve 31A can be rotated around the axis A1 and adjusted. The valve 31B can be rotated around the axis B1. As shown in FIG. 2B, when the adjustment valves 31 </ b> A and 31 </ b> B are rotated perpendicularly to the axis of the intake port 11, the portions other than the sub flow channel 21 in the intake port 11 are closed. In addition, the regulating valves 32A and 32B provided upstream of the auxiliary flow path forming portions 39A and 39B in the intake port 12 have the same configuration as the regulating valves 31A and 31B. That is, the regulating valve 32A and the regulating valve 32B can be rotated around the axes A2 and B2 extending so as to form an equal angle with respect to the plate-like member 39A and the plate-like member 39B. Portions other than the flow path 22 can be closed. Therefore, similarly to the case described with reference to FIG. 2A, also in the case of FIG. 2B, the adjustment is performed when the lift amount of the intake valve 3 is relatively small, for example, smaller than a predetermined value. The tumble T can be formed in the cylinder 8 by closing the valves 31A and 31B and the regulating valves 32A and 32B and allowing air to flow only through the auxiliary flow paths 21 and 22.

  Further, FIG. 2C is a cross-sectional view taken along line I-I of FIG. 1 for explaining an intake device according to the third embodiment of the present invention. The shapes of the auxiliary flow path forming portions 38 and 39 and the regulating valves 31 and 32 in the intake device of the present invention may be the shapes shown in FIG. In FIG. 2C, the auxiliary flow path forming portion 38 in the intake port 11 is a tubular member 38 arranged to extend in parallel to the intake port 11. On the other hand, in the intake port 12, a tubular member 39 similar to the tubular member 38 is similarly arranged as a sub-flow channel forming portion. The insides of these tubular members 38 and 39 serve as the auxiliary flow paths 21 and 22 as they are. As can be seen from FIG. 2 (c), the auxiliary flow path 21 in the intake port 11 is disposed on the intake port 12 side and on the lower side, and the auxiliary flow path 22 in the intake port 12 is on the intake port 11 side. It is arranged on the lower side. Therefore, the tubular member 38 and the tubular member 39 are disposed near the center and on the lower side in the cross section of the entire intake ports 11 and 12. As in the case of FIG. 2B, the tubular members 38 and 39, that is, the sub-channels 21 and 22 are not necessarily arranged symmetrically, and the tubular members 38 and 39 may not have a circular cross section. Good.

  Further, in FIG. 2C, the regulating valve 31 arranged on the upstream side of the sub flow path forming portion 38 is composed of two regulating valves 31A and 31B. As shown in the drawing, the axes A1 and B1 extend so as to pass through the center of the intake port 11 and the center of the auxiliary flow path forming portion 38. The adjustment valve 31A can rotate about the axis A1, and the adjustment valve 31B can rotate about the axis B1. As shown in FIG. 2C, when the adjustment valves 31 </ b> A and 31 </ b> B are rotated perpendicularly to the axis of the intake port 11, the portions other than the sub flow channel 21 in the intake port 11 are closed. The regulating valves 32A and 32B provided upstream of the auxiliary flow path forming portions 39A and 39B in the intake port 12 have the same configuration as the regulating valves 31A and 31B. That is, the regulating valve 32A and the regulating valve 32B can be rotated around the axes A2 and B2 extending through the center of the intake port 12 and the center of the sub-flow passage forming portion 39, respectively. Portions other than the sub-channel 22 can be closed. Therefore, similarly to the case described with reference to FIG. 2A, also in the case of FIG. 2C, the adjustment is performed when the lift amount of the intake valve 3 is relatively small, for example, smaller than a predetermined value. The tumble T can be formed in the cylinder 8 by closing the valves 31A and 31B and the regulating valves 32A and 32B and allowing air to flow only through the auxiliary flow paths 21 and 22.

FIG. 5 is a schematic perspective view for explaining an intake device according to a reference example of the present invention. In FIG. 5, instead of the auxiliary flow path forming portions 38 and 39, two partition members 95 and 96 that intersect perpendicularly with each other along the central axis X of the intake port 11 are included. These partition members 95 and 96 have a substantially “+”-shaped cross section as shown in FIG. In FIG. 5, instead of the regulating valves 31 and 32, approximately 90 ° fan-shaped regulating valves 41 to 44 are arranged upstream of the partition members 95 and 96. As shown in the drawing, the two upper and lower adjustment valves 41 and 43 can be rotated around the vertical axis C1 adjacent to the partition member 95 facing in the vertical direction, and the other two upper and lower adjustment valves 42 and 44 are vertically It can be rotated around a vertical axis D1 adjacent to the direction axis C1. Further, these regulating valves 41 to 44 can open and close each of the four flow paths 71 to 74 formed in the intake port 11 by the partition members 95 and 96. The four flow paths formed in the first intake port 11 are a flow path 71, a flow path 72, a flow path 73, and a flow path 74 clockwise from the upper left side, and adjustment valves corresponding to the respective flow paths are provided. The adjustment valve 41, the adjustment valve 42, the adjustment valve 43, and the adjustment valve 44 are clockwise from the upper left side. Note that the axes C1 and D1 around which the adjusting valve rotates may be oriented in the horizontal direction. In this case, for example, the adjusting valves 41 and 42 rotate around the axis C1, and the adjusting valves 43 and 44 rotate along the axis D1. Rotate around.

  FIG. 6A to FIG. 6C are cross-sectional views similar to FIG. 2 assuming a case where tumble is generated. As shown in these drawings, similar partition members 95 and 96 are also arranged in the other intake ports 12 arranged in parallel to the intake port 11. The four flow paths formed in the second intake port 12 are a flow path 81, a flow path 82, a flow path 83, and a flow path 84 clockwise from the upper left side, and adjustment valves corresponding to each of these flow paths are provided. The adjustment valve 51, the adjustment valve 52, the adjustment valve 53, and the adjustment valve 54 are clockwise from the upper left side.

In the reference example shown in FIG. 6A, when the lift amount of the intake valve 3 is relatively small, the adjustment valves 41 and 42 above the intake port 11 are closed and the adjustment valve above the intake port 12 is closed. 51 and 52 are closed. That is, the lower side of the entire cross section of the intake ports 11 and 12 is opened, so that the air is only in the lower passages 73 and 74 in the intake port 11 and the lower passages 83 and 84 in the intake port 12. To go through.

Further, in the reference example shown in FIG. 6B, when the lift amount of the intake valve 3 is relatively small, the adjustment valves 41 and 42 on the upper side of the intake port 11 and the lower side located on the intake port 12 side. The adjustment valve 44 is closed, and the adjustment valves 51 and 52 on the upper side of the intake port 12 and the adjustment valve 53 on the lower side located on the intake port 11 side are closed. That is, in the cross section of the entire intake ports 11, 12, the lower side and the outside are opened, so that the air is only in the lower passage 73 in the intake port 11 and the lower passage 84 in the intake port 12. To go through.

Further, in the reference example shown in FIG. 6C, when the lift amount of the intake valve 3 is relatively small, the adjustment valves 41 and 42 on the upper side of the intake port 11 and the intake port 12 are located on the opposite side. The adjustment valve 43 on the lower side is closed, and the adjustment valves 51 and 52 on the upper side of the intake port 12 and the adjustment valve 54 on the lower side located on the opposite side of the intake port 11 are closed. That is, in the cross section of the entire intake ports 11 and 12, the lower side and the inner side are opened, so that the air is only in the lower passage 74 in the intake port 11 and the lower passage 83 in the intake port 12. To go through.

  In the cases of FIGS. 6A and 6B, when the lift amount of the intake valve 3 is relatively small, the air is allowed to flow only downward in the cross section of the entire intake ports 11 and 12. As described above, the tumble T can be formed in the cylinder 8. Then, when the lift amount of the intake valve 3 is relatively small as in the case of FIG. 6 (c), the intake valve 11 and 12 are made to flow air only downward and near the center in the entire cross section of the intake ports 11 and 12. Since the amount of air flowing into the cylinder from the lateral side of the periphery decreases, a tumble T having a higher tumble strength than in the case of FIGS. 6A and 6B can be formed in the cylinder 8. .

FIGS. 7A to 7C are cross-sectional views similar to FIG. 2 assuming a case where a swirl (lateral vortex) is generated. In the reference example shown in FIG. 7A, when the lift amount of the intake valve 3 is relatively small, all the adjustment valves 41 to 44 of the intake port 11 are closed, and the adjustment valves 51 on the left side of the intake port 12; 53 is closed. That is, the rightmost portion of the cross section of the intake ports 11 and 12 is opened, so that air passes only through the right passages 82 and 84 in the intake port 12.

In the reference example shown in FIG. 7B, when the lift amount of the intake valve 3 is relatively small, all the adjustment valves 41 to 44 of the intake port 11 are closed and all the adjustment valves of the intake port 12 are closed. Open 51-54. In other words, the right half of the cross section of the entire intake ports 11 and 12 is open, so that air passes only through the four passages 81 to 84 in the intake port 12.

Further, in the reference example shown in FIG. 7C, when the lift amount of the intake valve 3 is relatively small, the adjustment valves 41 and 43 of the intake port 11 are closed and all the adjustment valves 51 to 51 of the intake port 12 are closed. 54 is opened. That is, most of the right side in the cross section of the intake ports 11 and 12 is opened, so that the air flows into the two flow paths 72 and 74 in the intake port 11 and the four passages in the intake port 12. Passes 81-84.

In the reference examples shown in FIGS. 7 (a) to 7 (c), the portion on the right side of the entire cross section of the intake ports 11 and 12 is in an open state, and the air flows only in the open flow path. pass. As a result, the air flowing into the cylinder 8 from the intake port turns in the circumferential direction (clockwise as viewed from above) along the inner wall of the cylinder 8, and a clockwise swirl (not shown) in the cylinder 8. Is formed. Similarly, when it is desired to form a counterclockwise swirl in the cylinder 8 as viewed from above, the positions of the intake port 11 and the intake port 12 shown in FIGS. 7A to 7C are switched. Thus, it is sufficient to open and close the regulating valves 41 to 44 and the regulating valves 51 to 54.

FIG. 8A to FIG. 8C are cross-sectional views similar to FIG. 2 assuming a case where tumble and swirl are generated. In the reference example shown in FIG. 8 (a), when the lift amount of the intake valve 3 is relatively small, all the adjustment valves 41 to 44 of the intake port 11 are closed, and the adjustment valves 51 on the upper side of the intake port 12; 52 is closed. That is, in the cross section of the entire intake port 11, 12, the portion on the right side and the lower side is opened, so that air passes only through the lower passages 83, 84 in the intake port 12. Become.

Further, in the reference example shown in FIG. 8B, when the lift amount of the intake valve 3 is relatively small, all the adjustment valves 41 to 44 of the intake port 11 are closed, and other than the lower right of the intake port 12 The regulating valves 51 to 53 are closed. That is, in the cross section of the entire intake ports 11, 12, the portion on the right side and the lower side is opened, so that air passes only through the lower right side passage 84 in the intake port 12. .

Further, in the reference example shown in FIG. 8C, when the lift amount of the intake valve 3 is relatively small, all the adjustment valves 41 to 44 of the intake port 11 are closed and adjustments other than the lower left of the intake port 12 are made. The valves 51, 52, 54 are closed. That is, in the cross section of the entire intake ports 11, 12, the portion on the right side and on the lower side is opened, so that air passes only through the lower left passage 83 in the intake port 12.

In the reference example shown in FIGS. 8 (a) to 8 (c), the portion on the right side and the lower side is open in the cross section of the entire intake ports 11 and 12, and the air is open. Pass only through the flow path. Thus, a tumble is formed for the same reason as described with reference to FIGS. 6A to 6C, and also described with reference to FIGS. 7A to 7C. For the same reason as above, a clockwise swirl (not shown) is formed in the cylinder 8. When it is desired to form a tumble and a swirl that is counterclockwise when viewed from above, the positions of the intake port 11 and the intake port 12 shown in FIGS. 8A to 8C are switched. Thus, it is sufficient to control the opening and closing of the regulating valves 41 to 44 and the regulating valves 51 to 54.

In the reference example described above, the case where the intake device of the internal combustion engine includes two intake ports 11 and 12 has been described. However, the number of intake ports of the intake device may be one, or three or more. There may be. 9 (a) and 9 (b) are cross-sectional views similar to FIGS. 2 (b) and 2 (c), respectively, for describing an intake device according to another embodiment of the present invention. In FIG. 9A, the secondary flow path forming portion 38 disposed in the single intake port 11 has two plates extending downward at a predetermined angle, for example, about 45 ° with respect to the vertical plane. It is comprised from the shape members 38A and 38B. The sub-flow channel 21 between the plate-like members 38 </ b> A and 38 </ b> B is disposed near the center and on the lower side in the entire cross section of the intake port 11. As a matter of course, the plate-like members 38A and 38B are not necessarily arranged symmetrically, and the intersection of the plate-like members 38A and 38B may be shifted from the center of the intake port 11. Furthermore, the same adjustment valves 31A and 31B as those in FIG. 2B are provided upstream of the plate-like members 38A and 38B so as to be rotatable around the vertical axes A1 and B1. Even in the intake device having such a single intake port 11, when the lift amount of the intake valve 3 is relatively small, the adjustment valves 31 </ b> A and 31 </ b> B are closed to allow air to flow downward in the intake port 11 and By flowing only through the sub-flow path 21 formed near the center, the tumble T can be formed in the cylinder 8 as described above.

  Further, as shown in FIG. 9 (b), even if the tubular member 38 serving as the auxiliary flow path forming portion arranged so as to extend parallel to the intake port 11 is arranged in the single intake port 11. Good. As can be seen from FIG. 9B, the tubular member 38 is disposed near the center and on the lower side in the cross section of the intake port 11. Further, the same adjustment valves 31A and 31B as those in FIG. 2C are provided upstream of the tubular member 38 so as to be rotatable about the vertical axes A1 and B1. Even in the intake device having such a single intake port 11, when the lift amount of the intake valve 3 is relatively small, the adjustment valves 31 </ b> A and 31 </ b> B are closed and the air is moved downward in the intake port 11 and By flowing only through the sub-flow path 21 formed near the center, the tumble T can be formed in the cylinder 8 as described above.

Furthermore, in yet another embodiment of the present invention, the intake device of the internal combustion engine may include more than two intake ports. FIG. 9C is a cross-sectional view similar to FIG. 6 for describing an intake device according to still another reference example of the present invention. In the reference example shown in FIG. 9C, the intake device of the internal combustion engine has three intake ports, that is, a first intake port 11, a second intake port 12 and a third intake port which are arranged close to each other in parallel. Port 13 is included. As shown in FIG. 9C, the same partition members 95 and 96 and adjusting valves as those described with reference to FIGS. 5 and 6 are provided in these intake ports 11, 12, and 13. It has been. The four flow paths formed in the third intake port 13 are a flow path 91, a flow path 92, a flow path 93, and a flow path 94 clockwise from the upper left side, and adjustments corresponding to each of these flow paths. The valves are referred to as a regulating valve 61, a regulating valve 62, a regulating valve 63, and a regulating valve 64 in the clockwise direction from the upper left side.

  In FIG. 9C, when the lift amount of the intake valve 3 is relatively small, for example, the upper adjustment valves 41 and 42 and the lower left adjustment valve 43 of the first intake port 11 are closed and the second intake port 12 is closed. The upper adjustment valves 51 and 52 are closed, and the upper adjustment valves 61 and 62 and the lower right adjustment valve 64 of the third intake port 13 are closed. In this case, as shown in the drawing, the lower right flow path 74 in the first intake port 11, the lower flow paths 83 and 84 of the second intake port 12, and the lower left flow path of the third intake port 13. Only air 93 flows. That is, the air flows near the center and in the lower side in the entire cross section of the first, second and third intake ports 11, 12, 13, thereby forming the tumble T in the cylinder 8 as described above. can do. As can be seen with reference to FIG. 6 (a), FIG. 6 (b) and FIG. 6 (c), in order to form the tumble T, the adjustment valve of each intake port is opened and closed differently from FIG. 9 (c). You may make it do.

  FIG. 9C assumes a case where a tumble is formed in the cylinder 8 when the lift amount of the intake valve 3 is relatively small. FIG. 7A, FIG. 7B and FIG. As in the case shown in (c), the first, second and third intake ports 11, 12, 13 are opened and closed to open and close the first, second and third intake ports 11, 12, A swirl can also be formed in the cylinder 8 by increasing the opening area on one side with respect to the central plane in the cross section of the entire 13. Further, the adjustment valves of the first, second and third intake ports 11, 12, 13 are opened and closed in accordance with the case shown in FIGS. 8 (a), 8 (b) and 8 (c), If the opening area on one side and the lower side with respect to the central plane in the cross section of the entire first, second and third intake ports 11, 12, 13 is increased, both tumble and swirl are provided in the cylinder 8. It is also possible to form. Furthermore, it is within the scope of the present invention to appropriately combine some of the embodiments described above.

1 is a longitudinal sectional view of a direct injection spark ignition internal combustion engine equipped with an intake device according to the present invention. (A) It is sectional drawing seen along the line II of FIG. 1 for demonstrating the intake device based on 1st embodiment of this invention. (B) It is sectional drawing seen along the line II of FIG. 1 for demonstrating the intake device based on 2nd embodiment of this invention. (C) It is sectional drawing seen along the line II of FIG. 1 for demonstrating the intake device based on 3rd embodiment of this invention. (A) is a longitudinal cross-sectional view of the internal combustion engine provided with the intake device when air flows only through a sub-flow path. (B) is a horizontal sectional view of an internal combustion engine provided with an intake device when air flows only through a sub-flow channel. It is a figure which shows the relationship between the lift amount and tumble strength of an intake valve in the internal combustion engine provided with the intake device based on this invention. It is a schematic perspective view for demonstrating the intake device in the reference example of this invention. (A) It is sectional drawing similar to FIG. 2 supposing the case where a tumble is generated. (B) It is sectional drawing similar to FIG. 2 supposing the case where a tumble is generated. (C) It is sectional drawing similar to FIG. 2 supposing the case where a tumble is generated. (A) It is sectional drawing similar to FIG. 2 supposing the case where a swirl is generated. (B) It is sectional drawing similar to FIG. 2 supposing the case where a swirl is generated. (C) It is sectional drawing similar to FIG. 2 supposing the case where a swirl is generated. (A) It is sectional drawing similar to FIG. 2 supposing the case where a tumble and a swirl are generated. (B) It is sectional drawing similar to FIG. 2 supposing the case where a tumble and a swirl are generated. (C) It is sectional drawing similar to FIG. 2 supposing the case where a tumble and a swirl are generated. (A) It is sectional drawing similar to FIG.2 (b) for demonstrating the intake device based on other embodiment of this invention. (B) It is sectional drawing similar to FIG.2 (c) for demonstrating the intake device based on other embodiment of this invention. (C) It is sectional drawing similar to FIG. 6 for demonstrating the intake device based on another reference example of this invention. (A) It is a figure which shows the relationship between the crank angle (horizontal axis) and the intake valve lift amount (vertical axis) in a general internal combustion engine. (B) It is a figure which shows the relationship between the intake valve lift amount (horizontal axis) and the tumble strength (vertical axis) in a general internal combustion engine. (A) It is a longitudinal cross-sectional view of the intake device for internal combustion engines of a prior art in case the lift amount of an intake valve is comparatively small. (B) It is a longitudinal cross-sectional view of the intake device for internal combustion engines of a prior art in case the lift amount of an intake valve is comparatively large.

2 ... Exhaust port 3 ... Intake valve 11, 12, 13 ... Intake port 21, 22 ... Sub-flow path 31, 32 ... Adjustment valve 38, 39 ... Sub-flow path forming means 41, 42, 43, 44 ... Adjustment valve 51, 52, 53, 54 ... Adjustment valves 61, 62, 63, 64 ... Adjustment valves 71, 72, 73, 74 ... Channels 81, 82, 83, 84 ... Channels 91, 92, 93, 94 ... Channels 95, 96 ... partition member

Claims (7)

At least one intake port opening into the combustion chamber of the internal combustion engine;
A movable valve mechanism that raises and lowers the intake valve that opens and closes the intake port to adjust the lift amount ;
A sub flow path forming means for forming a sub flow path extending parallel to the intake port in the intake port;
An intake adjustment valve that is provided upstream of the sub-flow path and opens and closes to flow air through the sub-flow path;
The sub-flow path is formed on the lower side of the transverse section in the transverse section of the entire at least one intake port, and the maximum lift amount of the intake valve adjusted by the movable valve mechanism is less than a predetermined value. An air intake device in which air is allowed to flow only through the sub-flow path by the air intake adjustment valve when the air flow is small.   2. The intake device according to claim 1, wherein the sub-flow channel is formed near a center of the cross section in a cross section of the entire at least one intake port.   There is one intake port, and the sub-flow passage forming means has two plate shapes extending so as to form a predetermined angle from an axis line in the intake port parallel to the intake port to an inner wall of the intake port. The intake device according to claim 1, wherein the auxiliary flow path is formed between the plate-like bodies that form the predetermined angle.   3. The intake device according to claim 1, wherein the intake port is a single member, and the auxiliary flow path forming unit is a tubular member disposed in the intake port. The intake ports are first and second intake ports parallel to each other;
The sub-flow passage forming means in the first intake port is a first partition means for partitioning the inside of the first intake port,
The secondary flow path forming means in the second intake port is a second partition means for partitioning the inside of the second intake port,
2. Each of the first partitioning means and the second partitioning means is disposed so as to incline downward from a center plane between the first intake port and the second intake port. Or the intake device of 2. The intake ports are first and second intake ports parallel to each other;
The sub-flow passage forming means in the first intake port forms a predetermined angle from the axis in the first intake port parallel to the first intake port to the inner wall of the first intake port. Two plate-like bodies each extending so that the first sub-channel is formed between the plate-like bodies forming the predetermined angle,
The sub-flow passage forming means in the second intake port forms a predetermined angle from the axis in the second intake port parallel to the second intake port to the inner wall of the second intake port. Two plate-like bodies each extending so that the second sub-flow channel is formed between these plate-like bodies forming the predetermined angle,
The first sub-flow path is disposed on the second intake port side and below in the first intake port, and the second sub-flow path is in the second intake port. The intake device according to claim 1, wherein the intake device is disposed on one intake port side and on a lower side. The intake ports are first and second intake ports parallel to each other;
The sub-flow passage forming means in the first intake port is a first tubular member disposed on the second intake port side and on the lower side in the first intake port, and the second intake port 3. The intake device according to claim 1, wherein the sub-flow passage forming means in the port is a second tubular member disposed on the first intake port side and on the lower side in the second intake port.

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