JP2004092420A - Start control device for internal combustion engine - Google Patents

Abstract

An appropriate intake air amount is secured to improve the startability of an internal combustion engine.
Kind Code: A1 A valve train for lifting an intake valve of an internal combustion engine, comprising a valve train capable of changing an opening amount of the intake valve. If the normal control is performed when the start of the internal combustion engine is started, the opening amount of the intake valve is set to a specific opening amount. During a predetermined period after the start of the internal combustion engine is started, the opening amount of the intake valve is made larger than the specific opening amount.
[Selection diagram] FIG.

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a start control device for an internal combustion engine.
[0002]
[Prior art]
Japanese Patent Application Laid-Open No. 2001-152888 discloses a valve gear for lifting (opening) an intake valve of an internal combustion engine, wherein the valve closing timing of the intake valve can be continuously changed. It has been disclosed. In the valve train described in the publication, the operation of the internal combustion engine is stopped in a state where the intake valve is closed at the latest timing (hereinafter, referred to as a maximum delay timing). The internal combustion engine is started with the valve closed.
[0003]
By the way, in starting the internal combustion engine, it is necessary to secure an appropriate intake air amount in order to obtain an ideal process of increasing the engine speed. However, in the above publication, when the most retarded timing is a timing later than the intake bottom dead center, the intake valve opens for a certain period even after the piston in the combustion chamber exceeds the intake bottom dead center. Will be. Therefore, while the internal combustion engine is being started (hereinafter referred to as engine finger starting), air once drawn into the combustion chamber is discharged from the combustion chamber to the intake passage by the piston, and as a result, The amount of air drawn into the room (the amount of intake air) is reduced. In order to prevent the intake air amount from decreasing during the start of the engine as described above, in the above-mentioned publication, the most retarded timing is a timing near the intake bottom dead center.
[0004]
[Problems to be solved by the invention]
As described above, when starting the internal combustion engine, there is a demand to secure an appropriate intake air amount in order to improve the startability. Therefore, an object of the present invention is to secure an appropriate intake air amount in order to improve the startability of an internal combustion engine.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, a first aspect of the present invention provides a valve train for lifting an intake valve of an internal combustion engine, the valve train including a valve train capable of changing a valve opening amount of the intake valve. In a start control apparatus for an internal combustion engine in which the opening amount of an intake valve is set to a specific opening amount when normal control is performed when the start of the engine is started, the intake valve is opened for a predetermined period after the start of the internal combustion engine. The valve opening amount is made larger than the specific valve opening amount. Here, the opening amount of the intake valve corresponds to the operating angle of the intake valve in the embodiment described later. Here, the predetermined period is, for example, from when the start of the internal combustion engine is started until the combustion of fuel in the combustion chamber is stabilized, or until the engine speed becomes equal to or higher than a predetermined value after the start of the internal combustion engine. Period. Further, the timing of increasing the opening amount of the intake valve for a predetermined period after the start of the internal combustion engine is, for example, when the fuel first burns in the combustion chamber after the start of the internal combustion engine, or when the ignition of the internal combustion engine is started. This is when the switch is turned on or when the starter of the internal combustion engine is turned on.
According to a second aspect, in the first aspect, the opening amount of the intake valve is made larger than the specific opening amount when fuel first burns in the combustion chamber after the start of the internal combustion engine.
In a third aspect based on the first or second aspect, the increased amount of the increased opening amount of the intake valve is set according to the temperature of the internal combustion engine.
According to a fourth aspect, in any one of the first to third aspects, when it is determined that the combustion of the fuel in the combustion chamber is stable, the opening amount of the intake valve is set in accordance with the normal opening amount control. To be opened.
In a fifth aspect, in the fourth aspect, when it is determined that the fuel combustion in the combustion chamber is stable and the idling operation is required for the internal combustion engine, the opening amount of the intake valve is required during the idling operation. Valve opening.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described with reference to the drawings. FIG. 1 shows a valve train according to the present invention. The valve train 1 of the present invention is mounted on, for example, a four-stroke compression self-ignition type diesel internal combustion engine, and lifts (opens) the intake valve 2. As shown in FIG. 1, the valve train 1 includes a cam 3, a rocker arm 4, and a driving force transmission mechanism 5 for transmitting a driving force from the cam 3 to the rocker arm 4. The driving force transmission mechanism 5 is arranged between the cam 3 and the rocker arm 4. The cam 3 is rotated around the center Cc by the driving force of the internal combustion engine. The rocker arm 4 abuts on the tip of each intake valve 2 and is capable of swinging about a swing axis Cr by the driving force from the cam 3 transmitted by the driving force transmission mechanism 5.
[0007]
As shown in FIG. 2, the driving force transmission mechanism 5 has an input arm 7 having a roller 6 and a pair of output arms 8. The input arm 7 and the output arm 8 are mounted on a control shaft 9 so as to be independently swingable around their axes. The input arm 7 comes into contact with the cam 3 via the roller 6. On the other hand, the output arm 8 comes into contact with the rocker arm 4.
[0008]
A gear mechanism 10 is mounted on the control shaft 9 so as to be able to swing around its axis. The gear mechanism 10 has a hole 13 extending in the circumferential direction. Since the pin 14 projecting from the control shaft 9 is engaged with the hole 13, the gear mechanism 10 cannot slide on the control shaft 9, but can swing on the control shaft 9. The gear mechanism 10 connects the input shaft 7 and the output shaft 8. Therefore, the driving force from the cam 3 input to the input shaft 7 is transmitted to the output shaft 8 via the gear mechanism 10.
The gear mechanism 10 has one helical gear 11 and a pair of helical gears 12 arranged on both sides thereof. A central helical gear (hereinafter, referred to as a central gear) 11 meshes with a helical spline (not shown) spirally provided on the inner peripheral wall surface of the input arm 7. The helical gears (hereinafter, referred to as side gears) 12 on both sides mesh with helical splines (not shown) spirally provided on the inner peripheral wall surface of the output arm 8.
[0009]
In the present invention, when the gear mechanism 10 is slid along the axial direction in the direction R shown in FIG. 2 by the control shaft 9, the gear mechanism 10 moves in the direction R with respect to the input arm 7 and the output arm 8. And move. In this case, the action between the helical gears 11 and 12 of the gear mechanism 10 and the helical splines of the arms 7 and 8 causes the angle between the input arm 7 and the output arm 8 about the axis of the control shaft 9 (hereinafter referred to as the angle). , The angle between the arms), the input arm 7 and the output arm 8 are rotated in opposite directions about the axis of the control shaft 9. The positional relationship between the input arm 7 and the output arm 8 when the gear mechanism 10 is most slid in the direction R shown in FIG. 2, that is, when the angle between the arms is maximized, is shown in FIG. It is shown in FIG.
[0010]
On the other hand, when the gear mechanism 10 is slid in the direction F shown in FIG. 2 along the axial direction by the control shaft 9, the gear mechanism 10 moves in the direction F with respect to the input arm 7 and the output arm 8. I do. In this case, by the action of the helical gears 11 and 12 of the gear mechanism 10 and the helical splines of the arms 7 and 8, the angle between the input arm 7 and the output arm 8 about the axis of the control shaft 9 (the arm The input arm 7 and the output arm 8 are turned around the axis of the control shaft 9 in opposite directions so that the angle between them becomes smaller. The positional relationship between the input arm 7 and the output arm 8 when the gear mechanism 10 is most slid in the direction F shown in FIG. 2, that is, when the angle between the arms is minimized, is shown in FIG. It is shown in FIG.
[0011]
As shown in FIG. 3A, the cam 3 is rotated in the direction R. However, while the portion of the cam 3 that is in contact with the roller 6 of the input arm 7 is the base circular portion C, Since the cam 3 does not swing the input arm 7 on the control shaft 9, the gear mechanism 10 is not caused to swing on the control shaft 9, and the output arm 8 is not caused to swing on the control shaft 9. Therefore, at this time, since the output arm 8 does not swing the rocker arm 4 around the swing axis Cr, the intake valve 2 is not lifted.
[0012]
On the other hand, as shown in FIG. 3B, when the projecting portion of the cam 3 comes into contact with the roller 6 of the input arm 7, the cam 3 swings the input arm 7 on the control shaft 9. The gear mechanism 10 is also swung on the control shaft 9, and the output arm 8 is also swung on the control shaft 9. At this time, the output arm 8 swings the rocker arm 4 around its swing axis Cr, so that the intake valve 2 is lifted.
[0013]
Here, in the example shown in FIG. 3, the angle between the input arm 7 and the output arm 8 (the angle between the arms) about the axis of the control shaft 9 is the largest, and therefore, the intake valve 2 Is lifted with the maximum working angle and the maximum lift. That is, the intake valve 2 is lifted with the maximum valve opening amount, and at this time, the amount of air sucked into the combustion chamber (intake amount) is the maximum amount.
[0014]
On the other hand, in the example shown in FIG. 4 as well, while the portion of the cam 3 in contact with the roller 6 of the input arm 7 is the base circle portion C, the output arm 8 moves the rocker arm 4 around its swing axis Cr. Since it does not swing, the intake valve 2 is not lifted. On the other hand, as shown in FIG. 4B, when the protrusion of the cam 3 comes into contact with the roller 6 of the input arm 7, the cam 3 swings the input arm 7 on the control shaft 9. , The output arm 8 is swung on the control shaft 9.
[0015]
However, in the example shown in FIG. 4, the angle between the input arm 7 and the output arm 8 (the angle between the arms) about the axis of the control shaft 9 is minimized. At this time, even if the output arm 8 swings on the control shaft 9, the output arm 8 does not swing the rocker arm 4 around its swing axis Cr, so that the intake valve 2 is not lifted, and The operating angle and the lift amount of the valve 2 are zero.
[0016]
In the present embodiment, the angle between the input arm 7 and the output arm 8 (the angle between the arms) about the axis of the control shaft 9 can be continuously changed between the largest angle and the smallest angle. It is. Therefore, according to the present embodiment, as shown in FIG. 5, the operating angle and the maximum lift of the intake valve 2 can be continuously changed. In the present embodiment, the operating angle of the intake valve 2 and its maximum lift amount are in a relationship such that as the operating angle of the intake valve 2 increases, the maximum lift amount of the intake valve 2 increases. Further, in the present embodiment, as the operating angle of the intake valve 2 increases, the amount of air drawn into the combustion chamber (intake amount) tends to increase. In FIG. 5, the horizontal axis indicates the operating angle, and the vertical axis indicates the lift amount.
[0017]
By the way, in the present invention, when starting of the internal combustion engine is started, cranking of the internal combustion engine is performed. Then, the fuel starts to be burned in the combustion chamber, and eventually the fuel is stably burned. Here, in order to stabilize the combustion of the fuel in the combustion chamber within a short time after the start of the internal combustion engine, a relatively large intake air amount should be secured to facilitate the combustion of the fuel in the combustion chamber. is there.
[0018]
On the other hand, according to the normal control for determining the operating angle of the intake valve in the present invention, the operating angle of the intake valve is set to an operating angle at which good exhaust emission is maintained or an operating angle at which high fuel efficiency is maintained. You. According to this normal control, the operating angle of the intake valve when the start of the internal combustion engine is started is set to an operating angle that is insufficient to secure a sufficient intake air amount to burn fuel. In particular, when the operation required for the internal combustion engine at this time is an idling operation, the operating angle of the intake valve is set to an extremely small operating angle. As described above, according to the normal control of the present invention, a sufficient intake air amount is not secured when the start of the internal combustion engine is started, so that the startability of the internal combustion engine cannot be satisfied.
[0019]
However, in the present invention, the operating angle of the intake valve 2 is increased during a predetermined period after the start of the start of the internal combustion engine. More specifically, in the first embodiment, the operating angle of the intake valve 2 is increased from the start of the internal combustion engine to the start of combustion of fuel in the combustion chamber (hereinafter, referred to as “starting the engine”). . In particular, in the first embodiment, when the fuel burns for the first time in the combustion chamber after the start of the internal combustion engine, the operating angle of the intake valve 2 is increased. That is, in this case, the working angle of the intake valve 2 is increased from the intake stroke that first arrives after the fuel is burned in the combustion chamber for the first time after the start of the internal combustion engine.
[0020]
For example, in a four-stroke internal combustion engine, as shown in FIG. 6, the intake stroke IN, the compression stroke CO, the expansion stroke PO, and the exhaust stroke EX are performed in each combustion chamber. When it is determined that fuel has burned for the first time in the expansion stroke PO indicated by, the working angle of the intake valve 2 is increased from the intake stroke IN indicated by 21 in FIG. According to this, the amount of intake air increases from the start of the internal combustion engine to the time when the combustion of the fuel in the combustion chamber is stabilized, so that the fuel is easily combusted in the combustion chamber. Is improved.
[0021]
Further, in the second embodiment of the present invention, the operating angle of the intake valve 2 is increased while the cranking of the internal combustion engine is performed after the start of the internal combustion engine is started. This also increases the amount of intake air during the cranking of the internal combustion engine after the start of the internal combustion engine is started, so that the fuel is easily combusted, and therefore, the startability of the internal combustion engine is improved. .
[0022]
In the above-described embodiment, it is determined that fuel has burned for the first time in the combustion chamber when the engine speed is equal to or higher than a predetermined engine speed (hereinafter, referred to as a first engine speed). . Further, in the above-described embodiment, when the engine speed is equal to or higher than the engine speed (hereinafter, referred to as the second engine speed) higher than the first engine speed, the fuel of the fuel in the combustion chamber is increased. It is determined that it is stable. Further, in the above-described embodiment, when the fuel starts to stably burn in the combustion chamber, the operating angle of the intake valve 2 is set to a value set by normal control, for example, the operating angle required for the internal combustion engine at this time. If the current operation is the idling operation, the operating angle required during the idling operation is set.
[0023]
Further, in the above-described embodiment, the engine speed is set to a predetermined value or more after the start of the internal combustion engine, or when the ignition switch is turned on, or the starter of the internal combustion engine is turned on. In such a case, the operating angle of the intake valve 2 may be increased.
[0024]
FIG. 7 is a time chart showing an example of transition of the operating angle of the intake valve when the operating angle of the intake valve is controlled according to the present invention when the start of the internal combustion engine is started. 7, (A) shows the operation state S of the ignition switch, (B) shows the engine speed N, (C) shows the operating angle A of the intake valve 2, and (D) shows the time t. ing.
[0025]
In the example of FIG. 7, the operation state S of the ignition switch is turned on at time t0. As a result, the starter of the internal combustion engine is operated, and cranking of the internal combustion engine is started, so that the engine speed N gradually increases. At this time, the target operating angle of the intake valve 2 is set to the second value β, and therefore, the operating angle A of the intake valve 2 is at the second value β.
[0026]
After the time t0, the cranking of the internal combustion engine is continuously performed, the engine speed N increases, and at a time t2, the fuel starts burning in the combustion chamber, and reaches the first engine speed N1. Here, in the example of FIG. 7, when the engine speed N reaches the first engine speed N1, it is estimated that the fuel has started to be burned in the combustion chamber, and the target operating angle of the intake valve 2 becomes the second operating angle. The value β is switched to the first value α. Therefore, the operating angle A of the intake valve 2 increases at a stretch toward the first value α, whereby the intake air amount increases and the engine speed N increases at a stretch.
[0027]
Eventually, at time t4, the combustion of the fuel in the combustion chamber is stabilized, and the engine speed N reaches the second engine speed N2. Here, in the example of FIG. 7, when the engine speed N reaches the second engine speed N2, it is estimated that the fuel has started to stably burn in the combustion chamber, and the target operating angle of the intake valve 2 is reduced. Is returned to the second value β. Therefore, the operating angle A of the intake valve 2 decreases at a stretch toward the second value β. Here, even if the operating angle A of the intake valve 2 becomes small, the combustion of the fuel is already stable, so the engine speed N does not decrease rapidly, but gradually increases after time t4 and then gradually increases. After time t8, the engine speed changes near the engine speed Ni required at the time of idling.
[0028]
According to this, the startability of the internal combustion engine is improved. Further, according to this, the startability of the internal combustion engine is improved as compared with the case where the operating angle of the intake valve is not increased when the start of the internal combustion engine is started. FIG. 8 is a time chart showing an example of transition of the operating angle of the intake valve when the operating angle of the intake valve is not increased when the start of the internal combustion engine is started. In FIG. 8, (A) to (D) correspond to (A) to (D) in FIG.
[0029]
In the example of FIG. 8, the operation state S of the ignition switch is turned on at time t0. As a result, cranking of the internal combustion engine is started, so that the engine speed N gradually increases. At this time, in the example of FIG. 8, the target operating angle of the intake valve is set to the second value β, and therefore, the operating angle A of the intake valve is the second value β.
[0030]
After time t0, cranking of the internal combustion engine is continuously performed, the engine speed N increases, and eventually reaches the first engine speed N1 at time t2. Here, in the example of FIG. 8, even if the engine speed N reaches the first engine speed N1, the target operating angle of the intake valve cannot be switched at all. Therefore, the operating angle A of the intake valve remains at the second value β. For this reason, even after time t2, the engine speed N continues to increase, but the average rate of increase is small, and therefore, even at time t8, the engine speed Ni required at idling has not been reached. Thus, in the example of FIG. 8, the startability of the internal combustion engine is lower than in the present invention.
[0031]
By the way, in order to maintain good exhaust emission or high fuel efficiency, it is preferable that the increase in the operating angle of the intake valve, which is increased after the start of the internal combustion engine according to the present invention, is small. . Therefore, the increase in the operating angle of the intake valve should be set as small as possible in consideration of the startability of the internal combustion engine and the exhaust emission or fuel consumption. Here, the startability of the internal combustion engine is closely related to the combustibility of the fuel in the combustion chamber, and the higher the combustibility of the fuel, the smaller the increase in the operating angle of the intake valve is. The startability of the internal combustion engine as described above can be ensured.
[0032]
Therefore, in the above-described embodiment, the increase in the operating angle of the intake valve 2 that is increased after the start of the internal combustion engine is set according to the temperature of the internal combustion engine. Specifically, the higher the temperature of the internal combustion engine, the higher the combustibility of the fuel. Therefore, the increase in the operating angle of the intake valve 2 is set smaller as the temperature of the internal combustion engine is higher. According to this, the desired startability of the internal combustion engine is secured and the exhaust emission is maintained at a satisfactory level, or the desired startability of the internal combustion engine is secured and the fuel efficiency is maintained high. The temperature of the internal combustion engine is estimated, for example, from the temperature of cooling water for cooling the internal combustion engine or the temperature of lubricating oil for lubricating the inside of the internal combustion engine.
[0033]
In the present invention, the gear mechanism 10 of the valve train 1 is normally slid on the control shaft 9 by hydraulic pressure from a mechanical hydraulic pump driven by the driving force from the internal combustion engine. However, during engine start, the engine speed is low, the hydraulic pressure from the hydraulic pump is low, and the gear mechanism 10 cannot slide on the control shaft 9 sufficiently to increase the operating angle of the intake valve 2. Therefore, in the present invention, the gear mechanism 10 is made drivable by hydraulic pressure from an electric hydraulic pump, and during engine startup, hydraulic pressure from this electric hydraulic pump and mechanical hydraulic pump is used. Alternatively, the gear mechanism 10 is slid on the control shaft 9 by hydraulic pressure from only the electric hydraulic pump.
[0034]
FIG. 9 shows an example of a flowchart for controlling the operating angle of the intake valve according to the present invention when the engine is started. In the flowchart shown in FIG. 9, first, at step 10, it is determined whether or not the ignition flag Fig is set (FIG = 1). Here, the ignition flag FIG is a flag that is set when the ignition switch is turned on and reset when cranking of the internal combustion engine ends. When it is determined in step 10 that FIG = 1, the routine proceeds to step 11. If it is determined in step 10 that FIG = 0, the routine ends.
[0035]
In step 11, the electric hydraulic pump is operated, and then in step 12, cranking of the internal combustion engine is started, and then the routine proceeds to step 13.
[0036]
In step 13, it is determined whether or not the engine speed N is equal to or greater than a predetermined first engine speed N1 (N ≧ N1). Here, the first engine speed N1 is the first engine speed in the above-described embodiment. When it is determined in step 13 that N <N1, the routine returns to step 13 again. That is, step 13 is repeated until it is determined in step 13 that N ≧ N1. On the other hand, when it is determined in step 13 that N ≧ N1, the routine proceeds to step 14 in which the target operating angle A of the intake valve 2 is set to a predetermined first value α. Therefore, by this, the valve train 1 is driven such that the operating angle of the intake valve 2 becomes the predetermined first value α. Note that the first value α is the first value in the above-described embodiment.
[0037]
Next, at step 15, it is determined whether or not the engine speed N is equal to or higher than a predetermined second engine speed N2 (N ≧ N2). Here, the second engine speed N2 is the second engine speed in the above-described embodiment. If it is determined in step 15 that N <N2, the routine returns to step 15 again. That is, step 15 is repeated until it is determined in step 15 that N ≧ N2. On the other hand, when it is determined in step 15 that N ≧ N2, the routine proceeds to step 16 in which the target operating angle A of the intake valve 2 is set to a predetermined second value β. Therefore, by this, the valve train 1 is driven such that the operating angle of the intake valve 2 becomes the second predetermined value β. Note that the second value β is the second value in the above-described embodiment.
[0038]
In the embodiment described above, an electric actuator may be used instead of the electric hydraulic pump. In this case, the valve gear can be driven by an electric actuator, and when the operating angle of the intake valve should be increased during engine start according to the present invention, the hydraulic pressure from the mechanical hydraulic pump and the pressure from the electric actuator are used. The valve gear is driven by power or only by power from an electric actuator to increase the operating angle of the intake valve.
[0039]
Further, when the operation of the internal combustion engine is stopped for various reasons (for example, structural reasons of the valve gear), the operating angle of the intake valve naturally becomes a specific operating angle, and the internal combustion engine is started. When the engine is started, the intake valve is lifted by the specific operating angle. Here, the specific operating angle is set such that the combustion of the fuel is started within a short time after the start of the internal combustion engine. The present invention can also be applied to a case where the operating angle is such that only an insufficient amount of intake air is secured to stabilize.
[0040]
Further, when the operation of the internal combustion engine is stopped for various reasons, the operating angle of the intake valve is forcibly set to a specific operating angle, and when the internal combustion engine is started, this specific operating angle is started. The intake valve is then lifted, where this particular operating angle is insufficient to stabilize fuel combustion within a short time after the start of the internal combustion engine. The present invention is applicable to a working angle in which only an amount is secured.
[0041]
【The invention's effect】
According to the first aspect, the opening amount of the intake valve is increased for a predetermined period after the start of the internal combustion engine, so that the startability of the internal combustion engine is improved. That is, according to the present invention, an appropriate intake air amount is secured in order to improve the startability of the internal combustion engine.
In addition, it is necessary to secure an appropriate intake air amount especially when fuel is first burned in the combustion chamber after the start of the internal combustion engine. Here, according to the second aspect of the invention, when fuel is burned for the first time in the combustion chamber after the start of the internal combustion engine, the opening amount of the intake valve is increased, so that a more efficient and appropriate intake amount is secured. You.
Further, the startability of the internal combustion engine is affected by the temperature of the internal combustion engine. Here, according to the third aspect, the increase in the opening amount of the intake valve is set in accordance with the temperature of the internal combustion engine, so that a more accurate and appropriate intake amount is secured.
Further, when the combustion of the fuel in the combustion chamber is stabilized, it is no longer necessary to increase the opening amount of the intake valve. Here, according to the fourth invention, in this case, the opening amount of the intake valve is set to the opening amount set according to the normal opening amount control, so that a more accurate and appropriate intake amount is secured. Is done.
Further, when the combustion of the fuel in the combustion chamber is stabilized, it is no longer necessary to increase the opening amount of the intake air amount. At this time, when the idling operation is required for the internal combustion engine, the intake valve Should be the valve opening required during idling operation. Here, according to the fifth aspect, in this case, the opening amount of the intake valve is set to the opening amount required at the time of the idling operation, so that a more accurate and appropriate intake amount is secured.
[Brief description of the drawings]
FIG. 1 is a view showing a valve train of the present invention.
FIG. 2 is a diagram showing a driving force transmission mechanism of the valve train of the present invention in detail.
FIG. 3 is a view showing that the valve train of the present invention lifts the intake valve at the maximum operating angle.
FIG. 4 is a view showing a state in which the valve gear of the present invention lifts the intake valve with a minimum operating angle.
FIG. 5 is a view showing a lift curve of the intake air amount which can be achieved by the valve train of the present invention.
FIG. 6 is a diagram showing the timing at which each stroke is performed in each combustion chamber.
FIG. 7 is a time chart showing changes in the operating angle of the intake valve when the operating angle of the intake valve is controlled according to the present invention when the start of the internal combustion engine is started.
FIG. 8 is a time chart showing changes in the engine speed and the like when the operating angle of the intake valve is controlled according to a starting operating angle control different from the present invention.
FIG. 9 is a diagram showing an example of a flowchart for executing a start-up operating angle control according to the present invention.
[Explanation of symbols]
1. Valve train
2. Intake valve
3 ... Cam
4: Rocker arm
5. Driving force transmission mechanism
7 Input arm
8 Output arm
9 ... Control shaft
10 gear mechanism

Claims (5)

A valve operating device for lifting an intake valve of an internal combustion engine, comprising a valve operating device capable of changing an opening amount of the intake valve, wherein the intake valve operates according to normal control when starting of the internal combustion engine is started. In the start control device for an internal combustion engine in which the opening amount of the internal combustion engine is set to a specific opening amount, the opening amount of the intake valve is made larger than the specific opening amount for a predetermined period after the start of the internal combustion engine. A starting control device characterized by being operated. 2. The start control device according to claim 1, wherein when the fuel first burns in the combustion chamber after the start of the internal combustion engine, the opening amount of the intake valve is made larger than the specific opening amount. 3. The start control device according to claim 1, wherein the increased amount of the increased opening amount of the intake valve is set according to the temperature of the internal combustion engine. The valve opening amount of the intake valve is set to a valve opening amount set according to the normal valve opening amount control when it is determined that fuel combustion in the combustion chamber is stable. A starting control device according to any one of the preceding claims. When it is determined that fuel combustion in the combustion chamber is stable and idling operation is required for the internal combustion engine, the opening amount of the intake valve is set to the opening amount required during idling operation. The start control device according to claim 4.

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