JP2003343224A - Variable valve train of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable valve train of internal combustion engine, in which needed characteristics of valve-opening is obtained without using any other equipment by controlling an intake-air volume without using a throttle valve by advancing timing for closing an intake valve. <P>SOLUTION: The variable valve-train comprises an eccentric input shaft 18, an input link 32, one end of which is locked with the shaft 18 to convert the rotational motion to a reciprocating motion at the other end, a rocker cam 40 in linking openably with an engine valve, a drive link 36 and a control shaft 52. A drive link 36 converts the reciprocating motion at the connection point c to a rocking motion of the rocker cam 40 at a 2nd connection point d. The control shaft 52 changes a trajectory at the connection point c. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve operating system for an internal combustion engine capable of continuously variably controlling opening / closing timings and lift amounts of intake / exhaust valves according to operating conditions of an internal combustion engine for a vehicle.

[0002]

2. Description of the Related Art Conventionally, as a valve operating system for an internal combustion engine capable of continuously variably controlling the opening / closing timing and lift amount of intake / exhaust valves, there is an example described in Japanese Patent Application Laid-Open No. 11-107725.

In the above-mentioned conventional example, the rocker arm is interposed between the drive cam and the rocking cam so that the drive cam can rock the rocking cam and the central portion of the rocker arm can rock. By changing the rocking center position of the rocker arm by the supporting control cam, it is possible to variably control the valve opening / closing timing and the lift amount according to the operating conditions such as the engine speed.

[0004]

In the above-mentioned conventional valve operating system for an internal combustion engine, the peak position of the lift amount hardly changes when the valve opening / closing timing and the lift amount are variably controlled. That is, as shown in FIG. 8 of the above publication,
The peak position (horizontal axis position) where the lift amount is maximum is almost the same when the lift amount is large (high speed) and small (low speed), and the valve opening curve and the valve closing curve are almost centered around the peak position. The characteristics change symmetrically.

Therefore, when the mechanism of the conventional valve operating device is applied to the intake valve, in addition to the valve operating device, the drive cam and the engine crank are used in order to achieve the optimum opening / closing timing and lift amount required by the engine. It was inevitable to use it together with a phase variable control device that changes the rotational phase with the shaft. There is also a problem that it is difficult to reduce the so-called pumping loss by eliminating the throttle valve that controls the intake air amount of the engine.

That is, in order to control the intake air amount only by controlling the lift amount of the intake valve and the opening / closing timing without using the throttle valve, in order to control the intake air amount when the load of the engine is small and the lift amount of the valve is small, FIG. It is necessary to close the intake valve earlier than in the above case, and for that reason, it is necessary to use the phase variable control device in combination with the above.

Therefore, since the other valve variable control device is used together, the entire valve operating device becomes complicated, and two control devices for controlling these are required, and the entire system becomes complicated and the manufacturing cost becomes high. There is a problem.

The present invention has been made in view of the above-mentioned conventional problems, and the peak position of the lift amount can be automatically changed when the valve opening / closing timing and the lift amount are variably controlled. In that case, it is an object of the present invention to obtain the entire valve operating device that can obtain the required valve opening characteristics without using the above-described variable phase control device at a low manufacturing cost.

[0009]

In order to achieve the above-mentioned object, a device of the present invention according to claim 1 is a valve of an engine, an input eccentric shaft, and one end engaged with the input eccentric shaft for input. An input link that converts the rotational movement of the eccentric shaft into a reciprocating movement at the other end, a swing cam that links the valve of the engine so as to open the valve, and a first contact point that has one end engaged with the input link. A drive link for converting and transmitting the reciprocating motion of the above-mentioned reciprocating motion to the oscillating motion at the second contact which the other end engages with the oscillating cam, and the control means for changing the motion trajectory of the first contact. Characterize.

According to a second aspect of the present invention, a valve of an engine, an input cam shaft, a rocking cam linked to the valve of the engine so as to open the valve, and an input cam shaft are engaged. One end of the roller is rotatably supported at the first contact, and the other end is engaged with the swing cam that is swingable at the second contact,
Rotate the input cam shaft from the first contact to the second end on the other end side.
It is characterized in that it is provided with a drive link that converts and transmits the swing motion at the contact point and a control means for changing the position of the movement trajectory of the first contact point.

According to a third aspect of the present invention, in the first contact point, or in the vicinity of the first contact point of the input link or the drive link, a control arm which is swingable so as to draw an arc-shaped movement locus is used. It is characterized in that the position of the motion locus of the first contact is changed by changing the swing center position of the control arm supported.

According to the fourth aspect of the present invention, the change of the swing center position of the control arm is executed by the rotation of the control shaft having the same rotation center as the swing center of the swing cam. It is characterized in that it is configured in.

According to a fifth aspect of the present invention, the camshaft for the exhaust valve is an input eccentric shaft that opens the intake valve.

According to a sixth aspect of the present invention, in one bracket, the one of the input eccentric shaft and the input cam shaft and the swing center of the swing cam are arranged on the same plane. It is characterized by being supported by an internal combustion engine.

[0015]

According to the apparatus of the present invention as set forth in claim 1, the engine valve, the input eccentric shaft, and one end of which engages with the input eccentric shaft to rotate the input eccentric shaft at the other end. An input link for converting the reciprocating motion of the engine into a reciprocating motion, an oscillating cam that links the valve of the engine so that the valve can be opened, and a reciprocating motion at a first contact point where one end engages with the input link and the other end oscillates. Since a drive link that converts and transmits the swing motion at the second contact that engages with the moving cam and a control unit that changes the motion trajectory of the first contact are provided,
The rotation of the input eccentric shaft causes the swing cam to swing via the input link and the drive link, thereby opening the valve of the engine.

According to a second aspect of the present invention, there is provided an engine valve, an input cam shaft, a swing cam which is linked to the valve of the engine so as to open the valve, and an input cam shaft. One end of the engaging roller rotatably supports the first contact,
The other end is engaged with the swing cam that is swingable at the second contact, and the rotary motion of the input cam shaft is converted from the first contact to the swing motion at the second contact on the other end. Since the drive link and the control means for changing the position of the movement locus of the first contact point are provided, the input cam shaft swings the swing cam via the roller and the drive link, and the valve of the engine is opened. Open operation.

According to the third aspect of the present invention, the first contact point or the vicinity of the first contact point of the input link or the drive link can be swung so as to draw an arc-shaped movement locus. Since the position supported by the control arm is changed so as to change the swing center position of the control arm to change the position of the motion locus of the first contact, the vicinity of the first contact of the input link or the drive link is arcuate. While drawing the movement trajectory, the rocking cam is rocked to open the valve of the engine.

In the device of the present invention as defined in claim 4, the swing center position of the control arm is changed by rotating the control shaft having the same rotation center as the swing center of the swing cam. Since the control shaft is rotated, the position of the motion locus near the first contact point is changed by the rotation of the control shaft to change the characteristic of opening the valve of the engine.

According to the fifth aspect of the present invention, since the camshaft for the exhaust valve is the input eccentric shaft for opening the intake valve, the camshaft for the exhaust valve rotates. As a result, the rocking cam is rocked via the input link and the drive link to open the valve of the engine.

According to a sixth aspect of the present invention, in one of the input eccentric shaft and the input cam shaft,
One of the input eccentric shaft and the input cam shaft oscillates the adjacent oscillating cams because the oscillating centers of the oscillating cams are arranged on the same plane and are supported by the internal combustion engine with a common bracket. Then, the valve of the engine is opened.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. First, the main part of the valve train of the engine 10 will be described with reference to FIG. Note that FIG. 15 is a skeleton diagram of the main part of the valve train when the entire engine is viewed from the front. Cylinder head 1
An intake valve 14 and an exhaust valve 16 are arranged in a V shape in the two parts. Although not shown in detail, two intake valves 14 and two exhaust valves 16 are arranged side by side in the axial direction per cylinder.

Input eccentric shaft 1 for opening the intake valve 14
8 and an exhaust camshaft 20 for opening the exhaust valve 16
Includes a first sprocket 26 and a second sprocket 28 driven by a crankshaft 22 via a chain 24.
Are attached integrally.

1 and 2 show a variable valve operating device for an internal combustion engine according to the present invention, which is an example applied to a suction valve 14. FIG. 1 is a front view of a main part, and a part thereof shows a cross section. Figure 2
FIG. 2 is an external view seen from the upper side of FIG. 1, showing one cylinder.

The input eccentric shaft 18 is rotatably supported by the cylinder head 12 and a bracket 30 fixed to the cylinder head 12, and is rotationally driven by the crank shaft 22 (not shown) as described above. The input eccentric shaft 18 has a drive shaft 18b which is formed integrally with the drive shaft 18b and is eccentric from the rotation center a, and one end 32a of the input link 32 is rotatably engaged with the drive shaft 18b. The other end 32b of the input link 32 is swingably engaged with the central portion of the drive link 36 via the pin 34 at the first contact point c.

One end of the drive link 36 is swingably engaged with the arm portion 40a of the swing cam 40 via the pin 38 of the second communication contact d, and the other end is swingably engaged with the guide arm 44 via the pin 42.
Is swingably engaged with. The swing cam 40 is swingably supported by the cylinder head 12 and the bracket 30 fixed to the cylinder head 12, and has two cam portions 40b per cylinder.

The swing cam 40 swings by the drive link 36 as described later, so that the cam portion 40b can push down the intake valve 14 via the lifter 46 to open the valve. The two lifters 46 are slidably inserted into the holes 12a formed in the cylinder head 12, and the intake valve 1
4 is biased by a valve spring (not shown) and is normally on the upper side and closed as shown in FIG.

That is, as will be described later, when the rocking cam 40 rotates clockwise, the cam portion 40b pushes down the suction valve 14 together with the lifter 46 to open the valve, and the rocking cam 40 moves counterclockwise from this valve open state. When the suction valve 14 is rotated back and returned, the suction valve 14 is pushed up by the tension of the valve spring to close the valve. The guide arm 44 has one end engaged with the drive link 36 via the pin 42 as described above, and the other end swingably engaged with the end portion 48a of the control arm 48 via the pin 50. . The control arm 48 is integrated with the control shaft 52 and the pin 54.

The control shaft 52 is rotatably supported in the hole 40c of the swing cam 40, and its rotation is controlled by an actuator (not shown). That is, the swing cam 40 and the control shaft 52 are supported by the cylinder head 12 and the bracket 30 fixed to the cylinder head 12 so as to be rotatable or swingable about the same rotation center.

Next, the operation of the embodiment shown in FIGS. 1 and 2 will be described with reference to FIGS. 3 to 5 and FIG. The bracket 30 is omitted in FIGS. 3 to 5. When the input eccentric shaft 18 rotates clockwise, the input link 3 engaged with the drive shaft 18b that eccentrically rotates
2 converts the rotational movement into a reciprocating movement to convert the first contact c
In the drive link 36, the drive link 36 swings the swing cam 40 at the second contact d while being guided along the swing of the guide arm 44. The rocking cam 40 is rotated clockwise as described above, so that the cam portion 40 is rotated.
b presses the intake valve 14 together with the lifter 46 to open the valve.

The lift amount at which the intake valve 14 opens is determined by the swing range (swing angle) of the swing cam 40 and its position, and the basis thereof is the eccentric amount of the drive shaft 18b, that is, from the rotation center a to the eccentric center b. The specific swing range of the swing cam 40 and its position depend on the locus of the first contact point c, and the locus changes depending on the swing center of the guide arm 44.
That is, when the rotational direction positions of the control shaft 52 and the control arm 48 are at the positions shown in FIG. 1, the input eccentric shaft 18
Is rotated to reach the state shown in FIG. 3, the intake valve 14 is in the maximum lifted state (opened valve).

From here, the control shaft 52 and the control arm 4
When 8 is rotated clockwise by an actuator (not shown) to the position shown in FIGS. 4 and 5, the maximum lift of the intake valve 14 changes so as to reach the peak state shown in FIG. Comparison between FIG. 3 and FIG. 5 clearly shows the difference in the maximum lift amount of the intake valve 14. At this time, focusing on the eccentric center b of the input eccentric shaft 18 in the peak state of FIGS. 3 and 5, it can be seen that the rotational phases thereof are different. That is,
When the input eccentric shaft 18 rotates in the clockwise direction, the peak lift timing is earlier in FIG. 5 in which the peak lift amount of the intake valve 14 is smaller.

Therefore, the lift characteristics of the intake valve 14 are shown in FIG. In Fig. 14, the horizontal axis is the crankshaft 2
Rotation progresses from left to right as a rotation angle of 2, and is a lift characteristic (valve opening characteristic) when the vertical axis is the lift amount of the intake valve 14 and the exhaust valve 16. As can be seen from FIG. 14, the exhaust valve 16 has a general lift characteristic, but the lift characteristic of the intake valve 14 is greatly different between A and B. Characteristic A represents the case where the control arm 48 is in the position shown in FIG. 1 and FIG. 3, and the valve opening timing is before the closing of the exhaust valve 16 so that both valves 14 and 16 are in the overlapping state in which they are simultaneously opened. Therefore, the peak lift amount is large and the rotation range of the crankshaft 22 from the valve opening to the valve closing is wide.

On the other hand, the characteristic B represents the case where the control arm 48 is in the position shown in FIGS. 4 and 5, and the peak lift amount is small and the rotation range of the crankshaft 22 from the valve opening to the valve closing is narrow. , The peak lift timing is earlier than the characteristic A. Therefore, the characteristic B is significantly earlier than the characteristic A in the valve closing timing. The lift characteristic of the intake valve 14 is continuously changed steplessly between the characteristic A and the characteristic B by changing the rotation phase of the control arm 48 by an actuator (not shown) to change the locus of the first contact point c. be able to.

Accordingly, when the engine 10 is rotating at high speed, the lift characteristic close to the characteristic A is used, and when the engine 10 is rotating at low speed, the lift characteristic is close to the characteristic B. It becomes possible to drive.
Further, since the intake air amount of the engine 10 can be limited by reducing the lift amount of the intake valve 14 and significantly advancing the closing timing, it is possible to eliminate the throttle valve and reduce pumping loss. Become.

In this way, by changing the rotational phase of the control arm 48, the lift amount and the opening / closing timing of the intake valve 14 are greatly changed without using a device such as a phase variable control device as in the prior art. Since it is possible to change the peak lift position as well, it is possible to obtain optimum lift characteristics according to the rotation speed of the engine 10 at a low cost.

Further, in the embodiment shown in FIGS. 1 to 5, the rocking cam 40 and the control shaft 52 have the same shaft center, and the input eccentric shaft 18 is arranged beside them to form a single unit. Since the swing cam 40 and the input eccentric shaft 18 are supported by the cylinder head 12 by the bracket 30, the number of constituent parts is reduced and the height of the engine 10 is reduced when the variable valve operating device of the present invention is applied. There is also the advantage that it does not have to be raised.

Next, a second embodiment of the variable valve operating system for an internal combustion engine of the present invention will be described with reference to FIG. FIG. 6 corresponds to FIG. Here, only parts different from the embodiment shown in FIGS. 1 to 5 will be described, and description of substantially the same parts will be omitted.

The embodiment shown in FIG. 6 is different from the embodiment shown in FIG. 1 in the positional relationship between the swing cam 40 and the input eccentric shaft 18. That is, FIG. 6 is drawn with the intake valve 14 standing upright, but in this case, the input eccentric shaft 18 is arranged almost directly above the swing cam 40.
The rest of the configuration is the same as that of the embodiment shown in FIG. 1, and the operation is also the same, so the explanation is omitted.

In the embodiment shown in FIG. 6, the input eccentric shaft 18 is used.
Since the engine is arranged almost right above the rocking cam 40, the height of the engine is increased but it does not project laterally. Therefore, even if there is a space obstacle on the left and right of the rocking cam 40, it can be established. The advantage is that you can

Next, third and fourth embodiments of the variable valve operating device for an internal combustion engine of the present invention will be described with reference to FIGS. 7 and 8. 7 and 8 correspond to FIG. 1, respectively. Here, only parts different from the embodiment shown in FIGS. 1 to 5 will be described, and description of substantially the same parts will be omitted.

First, the relationship between FIGS. 7 and 8 will be described. 7 and 8 differ from each other in the inclination of the intake valve 14 and in the lateral positional relationship between the intake valve 14 and the input eccentric shaft 18 and the swing cam 40. That is, FIG. 7 is suitable for an engine in which the intake valve 14 is arranged on the right side of the cylinder,
FIG. 8 is suitable for an engine in which the intake valve 14 is arranged on the left side of the cylinder.

Therefore, in the engine in which the cylinders are arranged in the V-row, the cylinder in the left bank and the cylinder in the right bank are arranged as shown in FIG.
The embodiment shown in FIG. 8 can be used properly. The embodiment shown in FIGS. 7 and 8 is as described above.
Although there are differences in the left and right directions, the structures are substantially the same, and therefore the description will be given based on FIG. 7.

The input link 32 whose one end 32a is engaged with the input eccentric shaft 18 is connected to the drive link 36 via the pin 34 at the first connecting portion of c at the other end 32b.
The guide arm 44 is also engaged via the same pin 34, and the guide arm 44 is also engaged with an eccentric shaft 56 fixed to the control shaft 52 by a pin 54.

That is, when the control shaft 52 of the center e rotates, the eccentric shaft 56 of the center f also rotates integrally. As a result, the guide arm 44 swings about the center f as a swing center, so that the swing locus of the first connecting portion c changes. Thus, it can be seen that the eccentric shaft 56 serves the same role as the control arm 48 in the embodiment of FIG.

In the embodiment of FIG. 1, the guide arm 4
4 changes the locus of the first connecting portion c via the drive link 36, while the guide arm 44 is engaged with the pin 34 of the first connecting portion c in the embodiment of FIG. , The point that the movement locus is changed directly is different.

Further, the swinging cam 40, which the drive link 36 engages with the pin 38 and swings, is designed so that the cam portion 40b pushes the intake valve 14 through the rocker arm 58 to open it. That is, the rocker arm 58 is disposed between the adjuster 60 embedded in the cylinder head 12 and the intake valve 14, and the roller 62 rotatably provided at the center of the rocker arm 58 is configured to come into contact with the cam portion 40b. There is.

Although not shown in detail, the adjuster 60 has a function of adjusting a gap between the rocker arm 58 and the intake valve 14, and its head 60a serves as a fulcrum of the rocker arm 58. Therefore, the swing cam 40
Is swung clockwise from the state of FIG. 7, the cam portion 40b
Pushes down the central portion of the rocker arm 58 via the roller 62, so that the rocker arm 58 swings counterclockwise around the head 60a of the adjuster 60 as a fulcrum to push down the intake valve 14 to open the valve.

Next, the operation of the embodiment shown in FIG. 7 will be described. The embodiment of FIG. 7 also converts the rotational movement of the input eccentric shaft 18 into the oscillating movement of the oscillating cam 40 via the input link 32 and the drive link 36, similarly to the embodiment of FIG.
At this time, the swing angle and the swing range of the swing cam 40 are determined by the control shaft 5
The swing center f of the control arm 48 is displaced by the rotation of 2, so that the input link 32 and the drive link 36 change along with the locus of movement of the first contact point c connected by the pin 34.

That is, since the state of FIG. 7 corresponds to FIG. 1, when the input eccentric shaft 18 rotates clockwise, the amount of pushing down the intake valve 14 (valve lift amount) is large, but the control shaft 52 is opposite. When it is rotated about 90 ° in the clockwise direction, the swing center f of the control arm 48 is displaced to a state corresponding to FIGS. 4 and 5, and the swing angle and swing range of the swing cam 40 are both small. Therefore, the lift amount of the intake valve 14 is reduced.
The lift characteristic of the suction valve 14 is almost the same as that shown in FIG. 14, and the stepless and continuous change is also the same as in the embodiment of FIG.

Even in the embodiment shown in FIG. 8, the operation is the same as that described above, and the lift characteristic of the intake valve 14 is set to be the same as that in the embodiment of FIG. It can be applied to the engines arranged in rows, and can be used for the left and right banks of the V row together with the embodiment of FIG. 7. Further, the roller 6 is provided between the rocking cam 40 and the rocker arm 58.
Since 2 is provided, there is also an advantage that friction loss at the time of valve opening can be reduced.

7 and 8 are similar to the embodiments shown in FIG. 1 and subsequent drawings, the suction valve is changed by changing the rotational phase of the control shaft 52. Since the lift amount of 14 and the timing of opening and closing can be greatly changed, and the peak lift position can also be changed, it is possible to obtain optimum lift characteristics according to the rotational speed of the engine 10 and the like.

Further, the swing cam 40 and the control shaft 52 have the same shaft center, and the input eccentric shaft 18 is arranged beside them, and the swing cam 40 and the input eccentric shaft 18 are connected by one bracket 30. Since the cylinder head 12 is supported by the cylinder head 12, the number of constituent parts is reduced and the height of the engine 10 need not be increased when the variable valve operating device of the present invention is applied.

Next, fifth and sixth embodiments of the variable valve operating system for an internal combustion engine of the present invention will be described with reference to FIGS. 9 and 10. 9 and 10 are views corresponding to FIG. 1, respectively, and also correspond to FIGS. 7 and 8. Here, FIGS. 1 to 5 and FIGS.
Only the portions different from the embodiment shown in will be explained, and explanation of substantially the same portions will be omitted.

First, the relationship between FIGS. 9 and 10 will be described.
9 and 10 are similar to the relationships described in FIGS. 7 and 8,
The inclination of the intake valve 14 is different, and the positional relationship between the intake valve 14 and the input cam shaft 64 and the swing cam 40 in the lateral direction is different. Here, the input cam shaft 64 corresponds to the input eccentric shaft 18 in FIGS. 7 and 8. Therefore, FIG. 9 is suitable for an engine in which the intake valve 14 is arranged on the right side of the cylinder, and FIG. 10 is suitable for an engine in which the intake valve 14 is arranged on the left side of the cylinder.

Further, in the engine in which the cylinders are arranged in the V-row, the embodiments shown in FIGS. 9 and 8 can be selectively used for the cylinders in the left bank and the cylinders in the right bank. Figure 9
As described above, the embodiment shown in FIG. 10 has substantially the same structure although there is a difference in the left-right direction.
It will be explained based on.

The input cam shaft 64 is the crank shaft 22 (not shown).
Is driven to rotate and comes into contact with a roller 66 rotatably provided on one end side of the drive link 36.
The pin 68 that rotatably supports the
The drive link 36 can be driven. The drive link 36 is
It is engaged with the swing cam 40 via the pin 38 at the second contact d on the other end side, and converts the rotational movement of the input cam shaft 64 into the swing movement of the swing cam 40 and transmits it.

Therefore, in the embodiment shown in FIGS. 9 and 10, the input eccentric shaft 18 and the input link 32 in the embodiment shown in FIGS. 7 and 8 are replaced by the input cam shaft 64 and the roller 66. Will be different.

A spring 70 is engaged with the swing cam 40. Although not shown in detail, the spring 7
0 has one end fixed to the cylinder head 12 and the other end 70a
Is hung on the rocking cam 40 to constantly urge the rocking cam 40 in the counterclockwise direction. Therefore, the swing cam 40
Rotates in the clockwise direction by the input cam shaft 64, and returns in the counterclockwise direction by the urging force of the spring 70. Other configurations are the same as those in FIGS. 7 and 8, and thus description thereof will be omitted.

Next, the operation of the embodiment shown in FIG. 9 will be described. The operation of the embodiment of FIG. 9 is basically the same as that of the embodiment shown in FIG. 7, and as described above, the input eccentric shaft 18
And the input cam shaft 64 and the roller 6 instead of the input link 32.
The only difference is that 6 is located.

Therefore, the movement locus of the pin 68 (the first contact point c) for rotatably supporting the roller 66 is determined by the control shaft 5
By changing the rotation phase of No. 2, it is possible to greatly change the lift amount and the opening / closing timing of the intake valve 14, and it is also possible to change the peak lift position. The lift characteristics are almost the same as those shown in FIG. 14, and the fact that they continuously change continuously is also the same as in the embodiment shown in FIG.

Further, in addition to the roller 62 between the rocking cam 40 and the rocker arm 58, the roller 66 is also applied between the input cam shaft 64 and the drive link 36, so that the friction loss of the entire valve train is greatly reduced. There is a merit that it can be reduced to.

The configuration shown in FIGS. 9 and 10 is similar to the embodiments shown in FIGS. 1 and 1 and the embodiments shown in FIGS. By changing the rotational phase of the intake valve 14, the lift amount and the opening / closing timing of the intake valve 14 can be largely changed, and the peak lift position can also be changed. Lift characteristics can be obtained.

Further, the rocking cam 40 and the control shaft 52 have the same axis center, and the input cam shaft 64 is arranged beside them, and the rocking cam 40 and the input cam shaft 64 are connected by one bracket 30. Since the cylinder head 12 is supported by the cylinder head 12, the number of constituent parts can be reduced and the height of the engine 10 need not be increased when the variable valve operating device of the present invention is applied.

Next, seventh and eighth embodiments of the variable valve operating system for an internal combustion engine of the present invention will be described with reference to FIGS. 11 and 13. 11 and 13 respectively correspond to FIG. 1 and also correspond to FIGS. 7, 8 and 9 and 10. Here, only parts different from the embodiment shown in FIGS. 1 to 5 and FIGS. 7, 8 and 9 and 10 will be described, and description of substantially the same parts will be omitted.
Note that FIG. 12 is an external view of FIG. 11 seen from above, and corresponds to FIG.

First, the relationship between FIGS. 11 and 13 will be described. 11 and 13, the inclination of the intake valve 14 is different, and the left-right positional relationship between the input eccentric shaft 18, the swing cam 40, and the control shaft 52 is different, as in the relationship described in FIGS. 7 and 8.

That is, in FIG. 11, the right side is the input eccentric shaft 18, and the left side is the swing cam 40 and the control shaft 52. In FIG. 13, the left and right relationships are reversed.
11 and 13, the input eccentric shaft 18 also serves as the exhaust cam shaft 20. Therefore, FIG. 11 is suitable for an engine in which the intake valve 14 is arranged on the left side of the cylinder, and FIG. 13 is suitable for an engine in which the intake valve 14 is arranged on the right side of the cylinder.

Further, in the engine in which the cylinders are arranged in the V-row, the embodiments shown in FIGS. 11 and 13 can be used separately for the cylinders in the left bank and the cylinders in the right bank.
The embodiment shown in FIGS. 11 and 13 is as described above.
Although there are differences in the left and right directions, the structures are substantially the same, so the following description will be given based on FIGS. 11 and 12.

The intake valve 14 and the exhaust valve 16 are arranged in a V shape, and the swing cam 40 and the control shaft 52 having a coaxial center are arranged above the intake valve 14, and as described above, An input eccentric shaft 18 provided on the upper part of 16 also serves as an exhaust cam shaft 20. The input eccentric shaft 18 and the swing cam 40 of the intake valve 14 are connected by the input link 32 and the drive link 36 as in FIG. 1, but the input arm 32 is engaged by the guide arm 44. 1 is different from FIG.

That is, the input link 32 is the input eccentric shaft 1
The rotary motion of 8 is converted into a swing motion and transmitted to the drive link 36 through the pin 34 at the first contact point c, and its posture is determined by the swing of the guide arm 44.
Therefore, the movement locus of the first contact point c is also the guide arm 44.
The swing center of the guide arm 44 is controlled by the rotation of the control arm 48 integrated with the control shaft 52.

Next, the operation of the embodiment shown in FIG. 11 will be described. The embodiment of FIG. 11 is similar to the embodiment of FIG.
The rotary motion of the input eccentric shaft 18 is converted into the swing motion of the swing cam 40 via the input link 32 and the drive link 36. At this time, regarding the swing angle and swing range of the swing cam 40, the swing center f of the control arm 48 is displaced by the rotation of the control shaft 52, so that the input link 32 and the drive link 36 move to the pin 3 position.
It changes with the locus of movement of the first contact point c connected at 4.

That is, since the state of FIG. 11 corresponds to FIG. 1, when the input eccentric shaft 18 rotates clockwise, the amount by which the intake valve 14 is pushed down (valve lift amount) is large, but the control shaft 52 is in the clockwise direction. When rotated in the rotating direction, the control arm 48
The swing center f of is changed to the state corresponding to FIGS. 4 and 5, both the swing angle and the swing range of the swing cam 40 are reduced, and the lift amount of the intake valve 14 is reduced. The lift characteristic of the suction valve 14 is almost the same as that shown in FIG. 14, and the stepless and continuous change is also the same as in the embodiment of FIG.

Also in the embodiment shown in FIG. 13, the operation is similar to that described above, and the input link 32,
By arranging the drive link 36, the control arm 48 and the like so as to be point-symmetrical with FIG. 11, the lift characteristic of the intake valve 14 is set to be the same as that of the embodiment of FIG. It can be applied to the arranged engine and can be selectively used for the left and right banks of the V-row together with the embodiment of FIG.

Although the configuration and the operation are partially different, FIG.
Also in the embodiment shown in FIG. 13 and the embodiment shown in FIG. 1 and thereafter, by changing the rotation phase of the control shaft 52, the lift amount of the intake valve 14 and the opening / closing timing can be greatly changed. At the same time, the peak lift position can also be changed, so that optimum lift characteristics can be obtained according to the rotational speed of the engine 10.

Further, since the swing cam 40 and the control shaft 52 have the same shaft center and the exhaust cam shaft 20 of the exhaust valve 16 is also used as the input eccentric shaft 18, the intake valve 1
On the fourth side, the bracket 30 only has to support the swing cam 40 and the coaxial control shaft 52, which reduces the number of constituent parts and increases the height of the engine 10 when the variable valve operating device of the present invention is applied. The advantage of not having to raise the same is also the same.

Although the description of each of the above embodiments has been made on the variable valve operating device when applied to the intake valve 14, FIG.
Except for the embodiment of FIG. 1 and FIG. 13, it can also be applied to the exhaust valve 16. Although a detailed description is omitted, the synchronizing device of the present invention uses a roller bearing for each engaging portion (rotating portion) to reduce the rotational resistance, based on the general knowledge of those skilled in the art, so that the entire valve operating device can be used. It is possible to carry out improvements such as reducing the frictional resistance of (1) and combining with a control device that provides an appropriate valve opening characteristic.

[0076]

As described above, according to the device of the present invention, the following effects can be obtained. According to the apparatus of the present invention described in claim 1, one end of the valve of the engine, the input eccentric shaft, and the input eccentric shaft are engaged with each other, and the rotational motion of the input eccentric shaft is converted into the reciprocating motion at the other end. Input link, an oscillating cam that links the valve of the engine so as to open the valve, and a reciprocating motion at a first communication contact whose one end engages the input link, and the other end engages the oscillating cam. Since the drive link that converts and transmits the swing motion at the second contact point and the control means that changes the motion locus of the first contact point are provided, when the valve opening / closing timing and the lift amount are variably controlled, the lift It is possible to automatically change the peak position of the amount, and in that case, it is possible to obtain the entire valve operating device that can obtain the required valve opening characteristics without using the phase variable control device at a low manufacturing cost.

According to the apparatus of the present invention as defined in claim 2,
An engine valve, an input cam shaft, an oscillating cam linked to the valve so as to open the engine valve, and a roller engaged with the input cam shaft, one end of which is rotatably supported at a first contact point; The other end is engaged with the swing cam that is swingable at the second contact, and the rotary motion of the input cam shaft is converted from the first contact to the swing motion at the second contact on the other end. Since the drive link and the control means for changing the position of the movement trajectory of the first connecting point are provided, the peak position of the lift amount automatically changes when the valve opening / closing timing and the lift amount are variably controlled. Therefore, in this case, it is possible to obtain the entire valve operating device that can obtain the required valve opening characteristic without using the phase variable control device at a low manufacturing cost.

According to the device of the present invention as defined in claim 3,
The first contact point or the vicinity of the first contact point of the input link or the drive link is supported by a control arm that is capable of rocking so as to draw an arc-shaped motion trajectory, and the rocking center position of the control arm is changed, Since the position of the movement locus of the first contact point is changed, the valve opening characteristic can be changed only by changing the swing center position of the control arm. Therefore, control to the required valve opening characteristic with a simple actuator. You can

According to the apparatus of the present invention described in claim 4,
Since the change of the swing center position of the control arm is executed by the rotation of the control shaft having the same rotation center as the swing center of the swing cam, it is possible to increase the number of axes of the entire valve operating device. The required valve opening characteristic can be obtained, and the manufacturing cost can be reduced.

According to the apparatus of the present invention as defined in claim 5,
Since the camshaft for the exhaust valve is the input eccentric shaft that opens the intake valve, it is not necessary to provide an independent input eccentric shaft, so that the manufacturing cost of the entire valve gear can be reduced.

According to the apparatus of the present invention described in claim 6,
Since one of the input eccentric shaft and the input cam shaft and the swing center of the swing cam are arranged on the same plane and are supported by the internal combustion engine with a common bracket, these shafts are supported. Since the number of parts to be manufactured is reduced, the manufacturing cost of the entire valve train can be reduced.

[Brief description of drawings]

FIG. 1 is a front view of a main part of a variable valve operating device according to the present invention.

FIG. 2 is an external view of FIG. 1 viewed from the upper side.

FIG. 3 is a front view showing an operating state of FIG.

FIG. 4 is a front view showing another operating state of FIG.

5 is a front view showing another operating state of FIG. 1. FIG.

FIG. 6 is a front view of a second embodiment of the present invention.

FIG. 7 is a front view of a third embodiment of the present invention.

FIG. 8 is a front view of the fourth embodiment of the present invention.

FIG. 9 is a front view of the fifth embodiment of the present invention.

FIG. 10 is a front view of a sixth embodiment of the present invention.

FIG. 11 is a front view of the seventh embodiment of the present invention.

FIG. 12 is an external view of FIG. 11 viewed from the upper side.

FIG. 13 is a front view of an eighth embodiment of the present invention.

FIG. 14 is a diagram showing a valve lift characteristic in the variable valve actuation system of the present invention.

FIG. 15 is a skeleton diagram of the main part of a valve train of an internal combustion engine to which the variable valve train of the present invention is applied.

[Explanation of symbols]

10: Organization 12: Cylinder head 14: Intake valve 16: Exhaust valve 18: Input eccentric shaft 20: Exhaust cam shaft 22: Crankshaft 24: Chain 26: First sprocket 28: Second sprocket 30: Bracket 32: Input link 34: Pin 36: Drive link 38: Pin 40: Swing cam 42: pin 44: Guide arm 46: Lifter 48: Control arm 50: Pin 52: Control axis 54: pin 56: Eccentric shaft 58: Rocker Arm 60: Adjuster 62: Laura 64: Input cam shaft 66: Laura 68: Pin 70: Spring

Claims (6)

[Claims] 1. A valve of an engine, an input eccentric shaft, an input link for engaging one end of the input eccentric shaft to convert rotational movement of the input eccentric shaft into reciprocating movement at the other end, and A rocking cam that is linked to the valve so that the valve can be opened, and a reciprocating motion at a first communication contact whose one end engages with the input link and a second communication contact whose other end engages the rocking cam. A variable valve operating system for an internal combustion engine, comprising: a drive link which is converted to and transmitted to the swing motion of the control unit; and a control unit which changes a motion locus of the first contact. 2. A valve of an engine, an input cam shaft, a swinging cam that is linked to the valve of the engine so as to be capable of opening, and a roller that engages with the input cam shaft has a first contact point on one end side. Is rotatably supported, and the other end of the input cam shaft is engaged with the swing cam that is swingable at the second contact, so that the rotational movement of the input cam shaft is transferred from the first contact to the other end of the second contact. A variable valve operating apparatus for an internal combustion engine, comprising: a drive link that converts and transmits the swing motion at two contact points, and control means that changes a position of a motion locus of the first contact point. 3. The control arm, wherein the first contact point or the vicinity of the first contact point of the input link or the drive link is supported by a control arm that is swingable so as to draw an arc-shaped movement trajectory. 3. The variable valve operating system for an internal combustion engine according to claim 1, wherein the position of the center of swinging is changed to change the position of the movement trajectory of the first contact. 4. The change of the swing center position of the control arm is executed by rotating a control shaft having the same rotation center as the swing center of the swing cam. A variable valve operating system for an internal combustion engine according to claim 3. 5. A cam shaft for an exhaust valve is the input eccentric shaft that opens an intake valve.
5. A variable valve operating device for an internal combustion engine according to any one of 3 and 4. 6. One of the input eccentric shaft and the input cam shaft and the swing center of the swing cam are arranged on the same plane and supported by the internal combustion engine by a common bracket. The variable valve operating system for an internal combustion engine according to any one of claims 1 to 5, wherein