JP2009275598A - Intake device of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intake device of an internal combustion engine capable of controlling the strength of a tumble flow formed in a combustion chamber in a wide range by reducing intake resistance within an intake passage. <P>SOLUTION: An intake pipe 30 forms the intake passage 31 having a rectangular shape in cross section to lead air to the combustion chamber of the internal combustion engine. As for longitudinally cross sectional shapes of a pipe shaft direction of the intake pipe 30, a first inner wall 33 has a circular-arc recessed part 330 recessed in a circular-arc surface shape from the viewpoint of the intake passage 31 side, and a second inner wall 34 opposite to the first inner wall 33 has a low and planar step recessed part 340 from the viewpoint of the intake passage 31 side. A valve shaft 12 of an air current control valve 10 is provided on a pipe shaft direction upstream side of the step recessed part 340. The air current control valve 10 is fixed by the valve shaft 12, has a valve element 11 extending in a longitudinally cross sectional fan shape toward a distal end 13, and is rotated and driven. The valve element 11 sections an opening of the valve element intake passage 31 between the valve element 11 and the first inner wall 33 to lead air from a cut-out groove 15 formed at the distal end 13 to the combustion chamber side in an opening from a full closed position to a half-opened position. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

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

Conventionally, an intake device that arranges a control valve in an intake pipe that introduces air into a combustion chamber of an internal combustion engine, changes the opening cross-sectional area of the intake passage by adjusting the rotation angle of the control valve, and forms a tumble flow in the combustion chamber. Are known.
For example, in the intake device disclosed in Patent Document 1, air is guided from the notch into the combustion chamber when the valve is fully closed by providing a notch at the tip of the control valve to narrow the opening of the intake passage. A strong tumble flow. However, when the intake passage is opened and closed by a control valve with a notch at the tip, in the closed state, air flows only from the notch and an effective tumble flow is formed, but when the control valve is half open, the tip of the control valve and the intake air Since air also flows from the portion other than the notch between the inner wall of the tube, a strong tumble flow may not be formed.
For this reason, according to the intake device disclosed in Patent Document 1, a partition plate is provided in the intake pipe so as to form a tumble flow in a half-open state of the control valve, and the intake passage is divided to guide the air. However, when there is a partition plate in the intake pipe, in the fully opened state, the partition plate becomes an intake resistance, which causes a reduction in intake air.

JP 2006-283567 A

  An object of the present invention is to provide an intake device for an internal combustion engine that can reduce the intake resistance in the intake passage and control the strength of the tumble flow formed in the combustion chamber over a wide range.

According to the first aspect of the present invention, the intake pipe forms an intake passage having a rectangular cross section that guides air to the combustion chamber of the internal combustion engine. The inner wall of the intake pipe is formed in a generally arcuate surface in a concave shape when viewed from the intake passage side with respect to the shape of the longitudinal section of the intake passage in the tube axis direction, and the other side on the side opposite to the one side. The side is formed in a concave step surface when viewed from the intake passage side. A valve shaft perpendicular to the pipe axis direction and parallel to the step surface is provided at a low position when viewed from the intake passage side of the step surface, and a valve body fixed to the valve shaft is rotationally driven by an actuator.
The shape of the cross section along the tube axis direction of the valve body is a fan shape that extends toward the tip at a position far from the valve shaft. Furthermore, the tip of the valve body has a notch groove. While the valve body rotates in the range from the fully closed position to a predetermined opening, the notch groove and the arc surface of the intake pipe A gap is formed.

  In this way, when adjusting the opening area of the intake passage by rotationally driving the valve body having a fan-shaped tip and having a notch groove, from the fully closed position where the valve body closes the intake passage to a predetermined opening degree. While rotating the valve body, slide the tip of the valve body other than the notch against the arcuate surface of the intake pipe to prevent air leakage from other than the opening due to the notch, and allow air to enter only the opening. It can flow. For this reason, without increasing the intake resistance in the intake passage, the flow of the intake air in the intake pipe can be efficiently guided over a wide range to the combustion chamber side, and a strong and weak tumble flow can be formed in the combustion chamber.

  According to the second aspect of the present invention, the valve body is configured so that the tumble flow can be continued through the notch groove until the opening degree reaches from the fully closed angle to a large swing angle. For this reason, the strength of the tumble flow formed in the combustion chamber over a wide opening range can be controlled without providing another configuration in the intake passage.

  According to the third aspect of the present invention, the notch groove of the valve body is formed by notching the center side of the valve body tip, so that an opening is formed at the center of the intake passage from the fully closed state to a predetermined rotation angle. You can have it. As a result, the flow of intake air is efficiently strengthened and the intake air is introduced into the combustion chamber, so that an increase in pressure loss due to throttling can be suppressed and the tumble flow in the combustion chamber can be enhanced.

  According to the fourth aspect of the present invention, the valve body is provided on the inner wall forming the intake passage on the upstream side in the intake flow direction at a low position when viewed from the intake passage side of the stepped surface, so that the valve body is installed upstream of the intake passage. The side air is efficiently guided to the notch groove through the side surface facing the upstream side with the valve body standing up. Therefore, the strength of the tumble flow formed in the combustion chamber can be controlled by reducing the intake resistance.

  According to the fifth aspect of the present invention, the valve body has a rectangular flat plate-like support portion whose one side is fixed to the valve shaft, and a main body portion that is bent at one side facing the support portion and extends in a V shape is claimed. It has the structure equivalent to the valve body of the terms 1-3. That is, the main body portion extends from one side on the upstream side of the support portion, is formed in a sectional fan shape, and has a notch. In addition, one side on the upstream side of the support portion is provided so as to be located on the upstream side of the step surface in the valve-closed state. Since the valve body bent in such a V shape is inclined to the downstream side of the intake passage when fully closed, the friction loss due to the restriction of the air flow is reduced, and the air is more guided to the notch groove. It becomes easy. Further, the opening range within which the notch can be formed is increased, and the strength of the tumble flow formed in the combustion chamber can be controlled over a wider range by reducing the intake resistance in the intake passage.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
An intake device for an internal combustion engine according to a first embodiment of the present invention is shown in FIGS.
First, the overall configuration of the internal combustion engine 1 will be described with reference to FIG. The internal combustion engine 1 includes an engine body 2, an intake device 3, an exhaust gas device 4, a high pressure exhaust gas recirculation device (high pressure EGR device) 5, a low pressure exhaust gas recirculation device (low pressure EGR device) 6, an electronic control device (ECU) 7, and the like. Prepare.
The engine body 2 includes a cylinder 21 and a piston 22. A combustion chamber 23 is formed between the cylinder 21 and the piston 22.

The intake device 3 has an intake pipe 30 that forms an intake passage 31. The intake device 3 introduces intake air from the intake port 32 of the intake pipe 30 through the intake passage 31 to the combustion chamber 23 of the engine body 2. The intake pipe 30 includes an intake port and an intake manifold. The intake device 3 is provided with a supercharger 70, an intercooler 71, a throttle 72, a surge tank 73, an airflow control valve 10, a fuel injection device (injector) 74, and the like.
The exhaust gas device 4 has an exhaust gas pipe 40 that forms an exhaust gas passage 41. The exhaust gas device 4 guides the exhaust gas discharged from the engine body 2 to the exhaust port 42 of the exhaust gas pipe 40 through the exhaust gas passage 41. The exhaust gas device 4 is provided with a supercharger 70, an exhaust gas purification unit 43, and the like.

  The high pressure EGR device 5 includes a high pressure EGR passage member 50 that forms a high pressure EGR passage 51, and a high pressure EGR valve 52. The high pressure EGR passage member 50 connects the exhaust gas pipe 40 upstream of the supercharger 70 and the intake pipe 30 downstream of the throttle 72, and the high pressure EGR passage 51 communicates the exhaust gas passage 41 and the intake passage 31. The high pressure EGR valve 52 opens and closes the high pressure EGR passage 51 and controls the flow rate of the high pressure EGR gas that recirculates from the exhaust gas passage 41 to the intake passage 31.

The low pressure EGR device 6 includes a low pressure EGR passage member 60 that forms a low pressure EGR passage 61 and a low pressure EGR valve 62. The low pressure EGR passage member 60 connects the exhaust gas pipe 40 on the downstream side of the exhaust gas purification unit 43 and the intake pipe 30 on the upstream side of the supercharger 70, and the low pressure EGR passage 61 communicates the exhaust gas passage 41 and the intake passage 31. . The low pressure EGR valve 62 opens and closes the low pressure EGR passage 61, and controls the flow rate of the low pressure EGR gas that recirculates from the exhaust gas passage 41 to the intake passage 31.
ECU7 detects the driving | running state of a vehicle based on the information output from the accelerator sensor which is not shown in figure, an intake pressure sensor, a speed sensor, an engine speed sensor, a cooling water temperature sensor, etc., and controls each part of a vehicle.

Next, the structure of the intake pipe 30 and the airflow control valve 10, which are the main parts of the present embodiment, will be described in detail with reference to FIG. In the intake device 3, the intake pipe 30 includes an intake passage 31 having a rectangular cross-sectional shape inside, and the airflow control valve 10 is provided in the intake passage 31. The airflow control valve 10 includes a valve shaft 12 provided in the intake pipe 30 so as to be orthogonal to the pipe axis direction, and a valve body 11 fixed to the valve shaft 12.
The intake pipe 30 is connected to the engine body 2 on the left side of FIGS. 1 and 3 to 5, and the intake passage 31 communicates with the combustion chamber 23. The intake air introduced into the combustion chamber 23 through the intake passage 31 flows from the right side to the left side of the intake passage 31. Hereinafter, the right side of FIGS. 1, 3 and 4 is referred to as the upstream side of the intake air, and the left side is referred to as the downstream side.

  In the present embodiment, the inner wall constituting one side of the rectangular cross section of the intake passage 31 and the other inner wall facing the inner wall are the first inner wall 33 on the one side and the other side facing the first inner wall 33 on the other side. The second inner wall 34 is configured as follows. The first inner wall 33 includes a first inner wall inlet 331, an arc recess 330, and a first inner wall outlet 332 from the upstream side of FIG. The second inner wall 34 includes a second inner wall inlet 341, a step recess 35, and a second inner wall outlet 342 from the upstream side of FIG.

  The arc recess 330 is formed in the first inner wall 33 in a concave shape when viewed from the intake passage side so that the longitudinal section in the tube axis direction is substantially an arc surface. That is, the circular arc recess 330 is formed by notching the first inner wall 33 in a virtual cylindrical inner wall surface perpendicular to the tube axis direction, and the first inner wall 33 is upstream of the first inner wall inlet 331 and the downstream first inner wall outlet. It is divided into a part 332. Hereinafter, the end of the arc recess 330 on the first inner wall inlet portion 331 side is referred to as an arc recess inlet end 333, and the end of the first inner wall outlet portion 332 side is referred to as an arc recess outlet end 334.

  The step concave portion 35 is formed in the second inner wall 34 as a step surface whose longitudinal section in the tube axis direction becomes a concave shape when viewed from the intake passage side. In FIG. 1, the step recess 35 has a flat step bottom surface 340 that is parallel to the second inner wall 34 and one step lower than the second inner wall 34. Hereinafter, the upstream side of the stepped recess 35 of the second inner wall 34 is referred to as a second inner wall inlet 341, and the downstream side of the stepped recess 35 of the second inner wall 34 is referred to as a second inner wall outlet 342. With respect to the wall surfaces on both ends in the tube axis direction of the step recess 35, the upstream side is the step upper end side surface 343 and the downstream side is the step lower end side surface 344. The step upper side surface 343 and the step lower end side surface 344 are flat surfaces that face each other and are perpendicular to the step bottom surface 340.

  The valve shaft 12 of the air flow control valve 10 is adjacent to the first inner wall 33 and the second inner wall 34 of the intake pipe 30 adjacent to each other in the vicinity of the step upper end side surface 343 in the step recess 35, and an intake pipe inner wall side surface (not shown) that faces each other. Both ends are attached to the third inner wall and the fourth inner wall) and are rotatably installed. As shown in FIG. 3, one end of the valve body 11 is a shaft end 14 fixed so as to swing integrally with the valve shaft 12, and the other end, that is, the tip 13 on the valve tip side is cut into the central portion. A notch groove 15 is formed, and both sides of the notch groove 15 are formed in tip circular arc surfaces 131 and 132. The shapes of the tip arc surfaces 131 and 132 are arc shapes having substantially the same curvature as the arc concave portion 330 of the intake pipe 30.

  The shape of the longitudinal cross section of the valve body 11 in the direction of the pipe axis of the intake passage 31, that is, the shape of the cross section perpendicular to the valve shaft 12 is a substantially fan shape extending from the shaft end portion 14 toward the tip end 13. Further, when the upstream side surface of the intake passage 31 of the valve body 11 shown in FIG. The shape of the longitudinal section in the pipe axis direction lacking is a triangular shape in which the length on the valve body upper side surface 113 side from the shaft end portion 14 to the notch bottom surface 150 is shorter than the length on the valve body lower side surface 114 side. The notch groove 15 is formed in a long groove shape having a notch bottom surface 150 having an inclined flat surface in which the valve body upper side surface 113 side is deepened and the valve body lower side surface 114 side is shallowly formed in the center portion of the tip end 13. As shown in FIG. 1, the direction in which the notched bottom surface 150 is inclined is such that the valve body upper side surface 113 of the valve body 11 substantially coincides with the position of the arc recess outlet end 334 (“predetermined opening of claim 1”). At the opening degree corresponding to “degree”, the notch bottom surface 150 is set to be substantially parallel to the pipe axis direction of the intake pipe 30.

  The side surfaces of the valve body 11 at both ends in the rotational axis direction are formed in a planar shape in which the side surface 111 is slidable along the third inner wall of the intake pipe 30 and the side surface 112 is slidable along the fourth inner wall in the intake pipe 30. Further, the groove wall surfaces 151 and 152 on both end sides of the notch bottom surface 150 are formed in parallel to the third inner wall and the fourth inner wall at positions symmetrical to the left and right from the center of the tip end 13. When the shape of the valve body 11 is set as described above and the valve body 11 has the opening degree of FIG. 1, the arc recess 330 of the intake pipe 30, the groove side surfaces 151 and 152 of the notch groove 15, and the notch bottom surface 150. And the opening of the intake passage 31 is formed.

  According to the fully opened state shown in FIG. 4, the length along the longitudinal direction of the tube axis from the shaft end portion 14 of the valve body lower side surface 114 of the valve body 11 to the tip arc surfaces 131 and 132 of the tip 13 is a step. It is set to be slightly shorter than the length of the bottom surface 340 in the tube axis direction so that the tip arc surfaces 131 and 132 are positioned in the vicinity of the step bottom side surface 344 when fully open. Further, the thickness of the valve body 11 on the tip 13 side is set such that the valve body 11 is stored in the stepped recess 35. Thus, in this embodiment, when the valve body 11 is in the fully opened state, the valve body 11 is stored in the stepped recess 35 side of the intake pipe 30 so that the unevenness in the intake passage 31 when fully opened is reduced as much as possible.

Next, the operation of the airflow control valve 10 in the intake device 3 of the internal combustion engine according to the present embodiment will be described based on FIG. 2 and FIGS.
FIG. 5 shows a fully closed state where the airflow control valve 10 closes the intake passage 31. An actuator 8 shown in FIG. 2 is connected to the valve shaft 12 of the airflow control valve 10. When the ECU 7 determines the optimum rotation angle of the airflow control valve 10 based on conditions such as the rotational speed and load of the internal combustion engine, and transmits a control signal to the actuator 8, the actuator 8 transmits the airflow via the valve shaft 12 based on this control signal. The control valve 10 is driven to rotate.

  As shown in FIGS. 5 and 1, when an opening is formed between the valve body 11 and the first inner wall 33 of the intake pipe 30, the flow of the intake air in the intake passage 31 passes through this opening and the flow velocity It becomes a fast flow of. In the opening range from FIG. 5 to FIG. 1, the intake air is guided to the downstream side of the intake passage 31 from the notch groove 15 of the valve body 11, and the cylinder 21 is opened at the opening of the intake pipe 30 and the intake valve 26 of FIG. Flows into the combustion chamber 23 from the vicinity of the axial center. The flow of the intake air that has flowed into the combustion chamber 23 forms a strong tumble flow in the combustion chamber 23 along the wall surfaces of the cylinder 21 and the piston 22.

  The airflow control valve 10 has the notch groove 15 as the opening of the intake passage 31 in the range of the rotation angle from the fully closed position in FIG. 5 to the opening degree (hereinafter referred to as a half-open position) shown in FIG. The tumble flow thus formed can be formed in the combustion chamber 23. Here, comparing the half-open state of FIG. 1 of the first embodiment with the half-open state of the first comparative example in which a gap is opened between the tip of the valve body without a notch and the inner wall of the intake pipe, the opening cross section of the intake passage The shapes are different as shown in FIG. That is, according to the first embodiment, the height H of the notch opening cross section in the half-open state can be increased, and the friction loss on the inner wall surface when the intake air passes through the opening can be reduced. Further, by restricting the air flow to the center side by the width of the notch groove 15, it is possible to prevent the occurrence of a flow that hinders the formation of the tumble flow in the combustion chamber 23. As a result, as shown in FIG. 7, a stronger tumble flow can be formed as compared with the case of the half-open state of the first comparative example.

  Further, in the first embodiment, the air flow control valve 10 changes the opening height H of the notch shown in FIG. 6 within a large swing angle range between the fully closed position in FIG. 5 and the half-open position in FIG. Thus, the strength of the tumble flow can be appropriately adjusted according to the operating conditions of the internal combustion engine. Here, the distance between the notch bottom surface 150 and the first inner wall 33 in the cross-sectional shape in the tube axis direction that opens between the valve element 11 and the first inner wall 33 in the present embodiment is the opening height H1, and the valve The angle between the direction from the axial end portion 14 of the body 11 toward the distal end 13 and the downstream direction in the tube axis direction is defined as a rising angle θ, and will be specifically described with reference to FIG.

  FIG. 8 shows a change in the opening height H1 with respect to the rising angle θ of the valve body 11 by a solid line graph. Moreover, the effect by the shape of the valve body of 1st Embodiment is demonstrated compared with the 2nd comparative example shown in FIG. In the second comparative example, a flat valve body 91 having a notch at the tip is provided in the intake passage of the intake pipe 90 formed in the same shape as the intake pipe of the first embodiment. 8 shows a change in the intake passage opening height H2 with respect to the rising angle θ of the valve body 91 of the second comparative example.

  When the rising angle θ in the half-open state of the valve body 11 of the first embodiment is θ1, and the rising angle θ in the half-open state of the valve body 91 of the second reference example is θ2, the central portion of the valve bodies 11, 91, that is, the notch portion. The range of the rising angle θ in which only the opening is formed is a range indicated by a1 and a2 as “intake inflow only at the center of the valve body”. When the valve body 11 of the first embodiment is further rotated in the valve opening direction from the half-open state, the tip arc surface 131 and the tip arc surface 132 of the tip 13 are separated from the first inner wall 33, thereby opening the opening by the notch groove 15. A gap is further formed around the first inner wall 33 side. At this time, although the opening area of the intake passage 31 is increased, the flow rate of the intake air passing through the gap other than the notch groove 15 is relatively increased, so that the formation of the tumble flow is inhibited. The range of the rising angle θ of the valve bodies 11 and 91 forming this state is a range b1 and b2 shown as “intake inflow from other than the center of the valve body” in FIG.

  According to FIG. 8, in the first embodiment, the opening height H1 is varied in a wide range according to the rising angle θ of the valve body 11 in the opening range a1 where the intake air flows only into the notch groove 15 of the valve body 11. be able to. On the other hand, in the second comparative example, since the opening height H2 hardly changes in the opening range a2 in which the intake air flows only into the notch of the valve body 91, the flow of the intake air forming the tumble flow cannot be adjusted. As described above, according to the present embodiment, the air flow can be introduced downstream by concentrating the air flow only in the notch groove 15 portion over a wide range from the fully closed position to the half open position of the airflow control valve 10.

Further, according to the airflow control valve 10 of the present embodiment, the flow of intake air in the intake passage 31 can be adjusted as follows according to the operating conditions of the internal combustion engine.
When the internal combustion engine is fully loaded, the airflow control valve 10 is fully opened as shown in FIG. 4 and stored in the position of the step recess 340. Thereby, the unevenness | corrugation by the side of the 2nd inner wall 34 of the intake passage 31 can be eliminated, and intake resistance can be reduced.

  When the internal combustion engine is partially loaded, the airflow control valve 10 is in a half-open state shown in FIG. 1, and a notch bottom surface 150 forming the notch groove 15 is parallel to the first inner wall outlet 332 of the intake pipe 30. The opening area by 15 is maximized. Therefore, the pressure loss due to the restriction of the airflow control valve 10 can be reduced, and the tumble flow formed on the downstream side of the intake passage 31 can be strengthened.

  Further, when the internal combustion engine is started, the airflow control valve 10 is fully closed as shown in FIG. 5, and the opening formed by the notch groove 15 is reduced. The flow rate of the intake air introduced to the downstream side of the intake passage 31 through this opening can be increased, and a particularly strong tumble flow can be formed. Thereby, vaporization promotion of the fuel adhering to the inner wall of the intake pipe 30 can be promoted, emission can be reduced, and fuel consumption of the internal combustion engine can be improved.

(Second Embodiment)
An intake device for an internal combustion engine according to a second embodiment of the present invention is shown in FIGS. Components substantially the same as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted.
As shown in FIG. 9, the valve body 80 of the airflow control valve according to the second embodiment is formed in a V shape in which the main body portion 81 rises from the bent portion 841 of the support portion 84 having a rectangular flat plate shape. When the intake passage 31 is fully closed, the support portion 84 contacts the step bottom surface 340. One side of the support portion 84 facing the bent portion 841 is fixed to the valve shaft 82. In the fully closed state of FIG. 9, the bent portion 841 is located in the vicinity of the step upper end side surface 343 of the step recess 35. The main body 81 rises from the bent portion 841 so as to close the intake passage 31, and its tip 83 is slidably brought into contact with the circular arc recess 330 of the intake pipe 30. The shape of the longitudinal section in the tube axis direction of the main body 81 is a fan shape that extends from the bent portion 841 toward the tip 83, and the tip 83 is formed with a curvature along the arc recess 330, and a notch groove 85 is formed at the center thereof. Have. The notch bottom surface 850 of the notch groove 85 is parallel to the pipe axis direction of the intake pipe 30 when the valve body 80 shown in FIG. At this time, the valve body upper side 813 side of the tip 83 is positioned at the arc recess outlet end 334.

  According to the second embodiment, the opening of the intake passage 31 can be partitioned by the notch groove 85 from the fully closed state of FIG. 9 to the half-opened state of FIG. 10 with the main body 81 of the valve body 80 inclined. By this inclination, the change according to the opening degree of the valve body 80 of the opening height H3 of the intake passage 31 shown in FIG. 10 becomes gentle, and a sudden change in the opening cross-sectional area can be mitigated. Therefore, vortex formation downstream of the intake passage 31 can be prevented, intake resistance can be reduced, and intake air can be efficiently guided to the combustion chamber side. Further, the rotation angle range between the fully closed position and the half open position of the valve body 80 is increased, and the opening height H3 of the notch groove 85 can be adjusted more precisely.

(Other embodiments)
The shape of the valve body 11 and the main body 81 in the first and second embodiments described above is such that the valve body upper side surfaces 113 and 813 are planar, and the shape of the opening cross section by the notch grooves 15 and 85 is rectangular. However, in the valve body of the present invention, the side surface on the upstream side of the intake passage and the notch groove may be formed in other shapes. For example, as shown in FIG. 11, a concave arcuate surface that narrows toward the notch groove when viewed from the upstream side of the intake passage is provided on the side surface of the valve body, and the opening of the notch groove is formed in a substantially trapezoidal shape that narrows toward the tip, The shape may be such that the intake air is more easily guided from the central portion of the valve body tip.

Although the first and second embodiments described above are applied to a port injection type internal combustion engine that injects fuel in an intake pipe, the present invention may be applied to a direct injection type internal combustion engine that injects fuel in a combustion chamber.
Moreover, in the said 1st Embodiment, the internal combustion engine which does not have the low voltage | pressure EGR apparatus 6, the supercharger 70, the intercooler 71, etc. may be sufficient.
As described above, the present invention is not limited to the above-described embodiment, and can be applied to various embodiments without departing from the gist thereof.

1 is a cross-sectional view of a main part showing an intake device for an internal combustion engine according to a first embodiment of the present invention. 1 is an overall configuration diagram of an internal combustion engine according to a first embodiment of the present invention. The perspective view which shows the airflow control valve by 1st Embodiment of this invention. 1 is a cross-sectional view of a main part showing an intake device for an internal combustion engine according to a first embodiment of the present invention. 1 is a cross-sectional view of a main part showing an intake device for an internal combustion engine according to a first embodiment of the present invention. The comparison figure which shows the opening shape of the intake passage of 1st Embodiment of this invention, and a 1st comparative example, when the opening degree of a valve body exists in the middle half-open position from a fully closed position to a fully open position. The comparison figure which shows the strength of the tumble flow formed in the downstream of the intake device by 1st Embodiment of FIG. 6, and a 1st comparative example. The comparison figure which shows the height change of an opening when the angle from the intake pipe axis of the airflow control valve by 1st Embodiment of this invention and the 2nd comparative example shown in FIG. 12 is changed. The comparison figure which shows the flow of the intake air of the intake device of an internal combustion engine. The principal part sectional view showing the intake device of the internal-combustion engine by a 2nd embodiment of the present invention. The principal part sectional view showing the intake device of the internal-combustion engine by a 2nd embodiment of the present invention. Sectional drawing which shows the intake passage and valve body of a 2nd comparative example.

Explanation of symbols

  1: internal combustion engine, 2: engine body, 3: intake device, 10: air flow control valve, 11: valve body, 12: valve shaft, 13: tip, 131, 132: tip arc surface, 14: shaft end, 15 : Notch groove, 150: Notch bottom surface, 30: Intake pipe, 31: Intake passage, 32: Intake port, 33: First inner wall (one side of inner wall), 330: Arc recess (arc surface), 34: Second Inner wall (one side facing one side of the inner wall), 35: step recess (step surface)

Claims (5)

An intake pipe that forms an intake passage having a rectangular opening with a transverse cross section that guides air to the combustion chamber of the internal combustion engine;
A valve shaft provided in the intake pipe perpendicular to the pipe axis direction;
An actuator for rotationally driving the valve shaft;
A valve body fixed to the valve shaft and capable of adjusting an opening area of the intake passage according to a rotation angle;
With
On one side of the inner wall that forms the intake passage, an intake passage longitudinal cross-sectional shape in the tube axis direction forms a generally arcuate surface that is concave when viewed from the intake passage side,
On one side of the inner wall that forms the intake passage, the one side of the inner wall that faces the one side forms a stepped surface that is concave when viewed from the intake passage side in the pipe axis direction.
The valve shaft is provided parallel to the step surface at a low position when viewed from the intake passage side of the step surface,
The valve body has a fan shape in which a cross-sectional shape along the tube axis direction extends from the valve shaft toward the distal end of the valve body, and has a notch groove at the distal end.
From the fully closed position of the valve body to a predetermined opening, the tip slides along the arc surface and can be rotated with a gap formed by the notch groove and the arc surface. An internal combustion engine intake device.   2. The intake control apparatus for an internal combustion engine according to claim 1, wherein the valve body is configured to be able to maintain a tumble flow through the notch groove until the opening degree reaches a large swing angle from a fully closed angle. .   The intake device for an internal combustion engine according to claim 1 or 2, wherein the valve body has the notch groove at a center side of a tip thereof.   4. The intake device for an internal combustion engine according to claim 1, wherein the valve shaft is provided on the upstream side in the intake flow direction at a low position when viewed from the intake passage side of the stepped surface. 5. . An intake pipe that forms an intake passage having a rectangular opening with a transverse cross section that guides air to the combustion chamber of the internal combustion engine;
A valve shaft provided in the intake pipe perpendicular to the pipe axis direction;
An actuator for rotationally driving the valve shaft;
A valve body fixed to the valve shaft and capable of adjusting an opening area of the intake passage according to a rotation angle;
With
On one side of the inner wall that forms the intake passage, an intake passage longitudinal cross-sectional shape in the tube axis direction forms a generally arcuate surface that is concave when viewed from the intake passage side,
On one side of the inner wall that forms the intake passage, the one side of the inner wall that faces the one side forms a stepped surface that is concave when viewed from the intake passage side in the pipe axis direction.
The valve shaft is provided parallel to the step surface at a low position when viewed from the intake passage side of the step surface,
The valve body is composed of a rectangular flat plate-like support portion fixed on one side to the valve shaft, and a main body portion provided integrally on one side of the support portion facing the valve shaft.
The opposing sides of the support portion are provided on the upstream side at a low position when viewed from the intake passage side of the step surface,
In the cross-sectional shape along the tube axis direction of the intake passage of the valve body, the support portion and the main body portion have a V shape that is bent at one side facing the support portion, and the main body portion is the tube shaft. The cross-sectional shape along the direction is a fan shape that extends from one side of the support portion facing toward the distal end of the valve body, and has a notch groove at the distal end.
From the fully closed position of the valve body to a predetermined opening, the tip slides along the arc surface and can be rotated with a gap formed by the notch groove and the arc surface. An internal combustion engine intake device.

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