JP2002276316A - Variable valve train for internal combustion engine - Google Patents

Abstract

(57) [Problem] To surely prevent interference between an intake valve 1 and a piston at the time of a control failure or the like. SOLUTION: An operating angle control shaft 12 of an operating angle changing mechanism for changing an operating angle of an intake valve and a phase control shaft 28 of a phase changing mechanism for changing a center phase of the operating angle are arranged in parallel. The regulating mechanism 40 includes a slider 41 that moves in the axial direction with the rotation of the phase control shaft 12, and a stopper pin 42 fixed to the operating angle control shaft 12. A regulating cam 47 that engages with the stopper pin 42 is formed on the limiter 45 of the slider 41. The control shaft 12, the control shaft 12,
The rotation range of 28, that is, the operation of both change mechanisms is mutually and continuously regulated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operating angle changing mechanism for changing an operating angle (magnitude) of an intake valve or an exhaust valve (intake / exhaust valve), and an operation angle of the intake / exhaust valve with respect to a phase of a crankshaft. The present invention relates to a variable valve train for an internal combustion engine including a phase changing mechanism for changing a center phase (valve timing).

[0002]

2. Description of the Related Art In the field of internal combustion engines, the valve lift characteristics of intake and exhaust valves are highly controlled in accordance with engine operating conditions, and in order to obtain optimum operating characteristics, for example, the operating angle of an intake valve (and the valve lift amount) ), And a phase change mechanism that can continuously change the center phase of the operating angle has been proposed.

[0003]

In the case of using such a variable valve operating device, the operating angle changing mechanism and the operating angle changing mechanism can change the operating angle and the phase in order to increase the degree of freedom of control and to cope with a wide range of operating conditions. I want to secure the largest possible change range of the center phase by the mechanism. Also, it is desired to drive each change mechanism individually and independently.

[0004] However, if the change range is increased in this way, there is a possibility that the intake valve and the piston may interfere with each other near the top dead center of the exhaust gas. Specifically, when the operating angle of the intake valve is large, the center phase is greatly advanced, or when the central phase is advanced significantly, the operating angle is excessively increased. If the large operating angle and the advanced angle are performed at the same time, the intake valve and the piston may interfere with each other.

In order to avoid such interference between the intake valve and the piston, in practice, a control map or the like is preset so that the large operating angle and the advanced angle are not performed at the same time. . However, at the time of control failure or the like, there still remains a possibility that the intake valve and the piston come into contact with each other. If the initial change range of the two change mechanisms is set narrow in advance in order to reliably eliminate the possibility that the intake valve and the piston come into contact with each other, the degree of freedom in setting the valve lift characteristics of the intake valve is reduced. Operating characteristics cannot be obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and reliably prevents interference between an intake valve and a piston without narrowing an initial change range of an operating angle changing mechanism and a phase changing mechanism. One) is to avoid it.

[0007]

According to the present invention, there is provided a variable valve operating apparatus for an internal combustion engine according to the present invention, comprising: an operating angle changing mechanism for changing an operating angle of an intake valve or an exhaust valve; And a phase change mechanism that changes the rotation phase (with respect to the rotation phase). Each change mechanism is preferably continuously changeable within a preset initial change range. Examples of the phase changing mechanism include a type using a planetary gear as in the embodiment described later, a type using a helical gear, and a type using a vane.

The invention according to claim 1 is linked to both the operating angle changing mechanism and the phase changing mechanism, and mutually operates the operating angle changing mechanism and the phase changing mechanism.
It is characterized by having a regulation mechanism that regulates continuously.

By providing such a regulating mechanism,
The possibility of interference between the intake valve (or the exhaust valve) and the piston even during a control failure or the like can be reliably eliminated without previously setting the initial change range of the operating angle and the center phase by each change mechanism narrow. . Therefore, the reliability can be improved without sacrificing the degree of freedom in setting the valve lift characteristics. Furthermore, since the operation of the change mechanism is mutually and continuously controlled by the control mechanism, it is possible to minimize the change range that is actually controlled according to the engine operating state, and to reduce the valve lift characteristic. The degree of freedom of setting can be maximized.

[0010] For example, in the variable valve apparatus applied to the intake valve side as in the invention according to claim 2, when the operating angle of the intake valve is large and its center phase is advanced, the intake valve and the intake valve are connected to each other. Since there is a possibility of interference with the piston, the advancement side of the operating angle and the advancement side of the center phase may be regulated by the regulation mechanism.

More preferably, in order to further improve the degree of freedom in setting the operating angle and the center phase, the restricting mechanism responds to a change in the operating angle by the operating angle changing mechanism. Thus, the regulation amount of the center phase is continuously changed, and the regulation amount of the operating angle is continuously changed according to the change of the center phase by the phase changing mechanism.

According to the fourth aspect of the present invention, there is provided an operating angle control axis and a phase control axis disposed in parallel with each other, and the operating angle is changed by rotating the operating angle control axis, so that the phase control axis is changed. The rotation changes the center phase. A slider configured to move in the axial direction with rotation of one of the operating angle control axis and the phase control axis;
A stopper pin provided on the other control shaft,
The slider has a regulating cam that engages with the stopper pin.

According to the fourth aspect of the invention, the regulating mechanism has a simple structure mainly composed of the slider and the stopper pin, and the operating angle control shaft and the operating angle control shaft are appropriately set by appropriately setting the cam profile of the regulating cam. The rotation range of the phase control shaft can be mutually and continuously regulated.

More specifically, as in the invention according to claim 5, the slider is screwed to the outer periphery of the one control shaft so as to be slidably engaged with the outer periphery of the other control shaft. And a limiter that fits slidably outside,
A connector for integrally connecting the nut and the limiter, and the regulating cam is formed by an edge of the limiter.

In the invention according to claim 6, the operating angle changing mechanism includes a drive shaft to which rotational power is transmitted from a crankshaft, a drive eccentric cam provided eccentrically to the drive shaft, and a drive eccentric cam. A first link rotatably fitted to the outside, a control cam eccentrically provided on the operating angle control shaft, and a rocker arm rotatably fitted to the control cam and having one end connected to the first link. A swinging cam that is swingably provided on the drive shaft and drives the intake valve or the exhaust valve, and a second link connected to the other end of the rocker arm and the swinging cam. ing.

In the operating angle changing mechanism having such a configuration, since the swing cam for pressing the intake valve is arranged coaxially with the drive shaft, there is a possibility that the shaft may be misaligned between the swing cam and the drive shaft. In addition, the control accuracy is excellent, and the link elements such as the first and second links and the rocker arm are integrated around the drive shaft, so that the mechanism can be made compact.
In addition, since many of the connecting portions between the members are in surface contact, such as the bearing between the drive eccentric cam and the first link and the bearing between the control cam and the rocker arm, lubrication is easy and durability is high. Excellent in reliability and reliability. Further, even when the present invention is applied to a general internal combustion engine using a fixed cam and a camshaft, the swing cam and the drive shaft may be arranged at the positions of the fixed cam and the camshaft, and the layout change is very difficult. Since it requires only a small amount, it can be easily applied to existing internal combustion engines. Since the operating angle and the valve lift amount of the intake valve or the exhaust valve can be continuously adjusted to an arbitrary size according to the engine operating condition, the degree of freedom of setting is high, and the fuel consumption and the output according to the engine operating condition are high. The driving performance can be improved efficiently.

In the invention according to claim 7, the phase change mechanism is provided with a sun gear rotating in synchronization with a crankshaft, and a camshaft arranged coaxially around the sun gear to drive an intake valve or an exhaust valve. Alternatively, a ring gear that rotates integrally with the drive shaft, a planet gear that meshes with the outer periphery of the sun gear and the inner periphery of the ring gear, a carrier that supports the planet gear in a rotatable manner, and that is provided on the phase control shaft A phase control gear meshing with the outer periphery of the carrier;
have.

Therefore, when the sun gear rotates in synchronization with the crankshaft, the planetary gear meshing with the sun gear rotates on its own, and the ring gear meshing with the planetary gear rotates to rotate the camshaft or the drive shaft. .

Then, by rotating the phase control shaft according to the engine operating state, the carrier rotates around the sun gear, and the planetary gear revolves around the sun gear. As a result, the phase of the ring gear meshing with the planetary gear with respect to the sun gear changes, the phase of the camshaft or the drive shaft with respect to the crankshaft changes, and the center phase of the operating angle of the intake valve or the exhaust valve changes.

The phase change mechanism having such a configuration has a relatively simple structure in which a planetary gear mechanism is provided at one end of the drive shaft, and can be easily applied to an existing engine.
Since the center phase can be changed continuously, the degree of freedom of control is high.

According to an eighth aspect of the present invention, the regulating mechanism includes a first movable portion that is displaced with respect to an engine body in accordance with a change in the operating angle by the operating angle changing mechanism, and a center phase change by the phase changing mechanism. A second movable portion displaced with respect to the engine main body, a lever rotatably supported by the engine main body, one end of which can contact the first movable portion, and the other end of which can contact the second movable portion. The first movable portion or the second movable portion is displaced in accordance with one of the operation angle and the center phase, whereby the rotatable range of the lever is changed, and the operation angle and the center phase are changed. Is characterized in that the other changeable range changes.

According to the eighth aspect of the invention, the changeable range of the operating angle and the center phase can be mutually changed by the relatively simple regulating mechanism mainly including the first movable portion, the second movable portion and the lever. Can be regulated.

According to a ninth aspect of the present invention, the lever is moved to the first position.
It is characterized by having an urging means for urging in a direction in which it contacts the movable portion or the second movable portion.

According to the ninth aspect of the present invention, the followability of the lever to the first movable portion or the second movable portion is improved, and the operation response is improved.

According to a tenth aspect of the present invention, the first movable portion is a helical projection projecting from the outer periphery of an operating angle control shaft that is driven to rotate when the operating angle is changed.
A cam surface capable of abutting is formed at one end of the lever.

According to the tenth aspect of the present invention, the rotatable range in one direction of the lever can be continuously restricted with a relatively simple configuration by the cam surface of the projection.

[0027]

According to the present invention, by providing the regulating mechanism, the initial change range of the operating angle and the center phase by each changing mechanism is not set narrow in advance, and the intake valve (or the control valve) is also used during a control failure or the like. The possibility of interference between the exhaust valve) and the piston can be reliably eliminated. Therefore, the reliability can be improved without sacrificing the degree of freedom in setting the valve lift characteristics. Furthermore, since the operation of the change mechanism is mutually and continuously controlled by the control mechanism, it is possible to minimize the change range that is actually controlled according to the engine operating state, and to reduce the valve lift characteristic. The degree of freedom of setting can be maximized.

[0028]

FIG. 1 is a schematic configuration diagram showing a variable valve apparatus for an internal combustion engine according to a first embodiment of the present invention.
This variable valve apparatus mainly includes an operating angle changing mechanism 10 for continuously changing the operating angle of the intake valve 1 and the magnitude of the valve lift amount, and a crank angle of a central phase (valve timing) of the operating angle of the intake valve 1. A phase changing mechanism 20 that changes the rotation phase of the shaft.

First, the structure of the operating angle changing mechanism 10 will be described. A drive shaft 11 and an operating angle control shaft 12 which extend in parallel with each other in the cylinder row direction above the intake valve 1 have a cylinder head 2 (see FIG. 2). It is supported rotatably.
The drive shaft 11 is driven to rotate around its axis by rotational power transmitted from a crankshaft (not shown) via a phase changing mechanism 20 described later. A swing cam 13 that abuts against and presses the valve lifter 1 a of each intake valve 1 is rotatably fitted on the drive shaft 11, and a drive eccentric cam 14 that is eccentric with respect to the drive shaft 11. Is fixed for each cylinder, and a ring-shaped first link 15 is rotatably fitted on the outer periphery of the drive eccentric cam 14.
The operating angle control shaft 12 has a control cam 16 for each cylinder.
Are fixed eccentrically, and a rocker arm 17 is rotatably fitted on the outer periphery of the control cam 16. One end of the rocker arm 17 is connected to the tip of the first link 15, and the other end of the rocker arm 17 is connected to one end of a rod-shaped second link 18. The other end of the second link 18 is connected to the tip of the swing cam 13.

With this configuration, when the drive shaft 11 rotates in conjunction with the crankshaft, the drive eccentric cam 14
The first link 15 is substantially translated through the first link 15, and the rocker arm 17 connected to the first link 15 is connected to the control cam 16.
The swing cam 13 swings around, and the swing cam 13 swings via the second link 18. The swing operation of the swing cam 13 causes the intake valve 1
Is pressed, and the intake valve 1 opens and closes.

When the operating angle control shaft 12 is rotated in accordance with the engine operating state, the position of the control cam 16 which is the rocking center of the rocker arm 17 changes, and the rocker arm 17 rotates.
And the postures of the links 15 and 18 change. This allows
The swing range and phase of the swing cam 13 change, and mainly the magnitude of the operating angle and the valve lift of the intake valve 1 change.

The operating angle changing mechanism 10 having such a structure is
Since the swing cam 13 for pressing the valve lifter 1a of the intake valve 1 is arranged coaxially with the drive shaft 11, the swing cam 1
There is no possibility that the shaft 3 may be displaced from the drive shaft 11 and the control accuracy is excellent, and the link elements 15, 17, and
By consolidating around the drive shaft 11, the mechanism can be made more compact. Also, since many of the connecting portions between the members are in surface contact, such as the bearing between the drive eccentric cam 14 and the first link 15 and the bearing between the control cam 16 and the rocker arm 17, lubrication is achieved. Easy to do, durable,
Excellent reliability.

Further, when the present invention is applied to a general internal combustion engine using a fixed cam and a camshaft, the swing cam 13 and the drive shaft 11 are located at the positions of the fixed cam and the camshaft.
Can be arranged, and the layout change is very small, so that the present invention can be easily applied to an existing internal combustion engine.

Since the operating angle and valve lift of the intake valve 1 can be continuously adjusted to arbitrary values according to the engine operating condition, the degree of freedom of setting is high, and the fuel consumption and output can be adjusted according to the engine operating condition. And other driving performance can be effectively improved.

FIG. 2 shows a phase changing mechanism 20 using a planetary gear 21. The sprocket gear 22 receives rotation power from a crankshaft via a chain or a timing belt (not shown) and rotates in synchronization with the crankshaft.
Is provided integrally with a sun gear 23. On the other hand, a ring gear 24 is integrally provided at one end of the drive shaft 11, and the ring gear 24 is coaxially arranged around the sun gear 23. The planet gears 21 are rotatably supported around support pins 26 provided on the carrier 25, and are intermittently arranged at four locations in the circumferential direction. Each planetary gear 21 meshes with the outer periphery of the sun gear 23 and the inner periphery of the ring gear 24.

On the outer periphery of the carrier 25, a phase control shaft 28
Is engaged with a phase control gear 27 fixed to one end.
The phase control shaft 28 extends in the cylinder row direction in parallel with the drive shaft 11 and the operating angle control shaft 12, and is rotatably supported by the cylinder head 2.

With this configuration, when the sprocket gear 22 rotates in synchronization with the crankshaft, the planet gear 21 meshing with the sun gear 23 rotates around the support pin 26 and the ring gear 2 meshes with the planet gear 21.
4 rotates, and the drive shaft 11 is rotationally driven. In addition, 4
In the case of a cycle engine, the reduction ratio from the sun gear 23 to the ring gear 24 is set to 2 so that the drive shaft 11 rotates at half speed with respect to the crankshaft.

Further, the phase control shaft 2 depends on the engine operating state.
8, the carrier 25 rotates around the sun gear 23 via the phase control gear 27, and the planetary gear 2
1 revolves around sun gear 23. As a result, the phase of the ring gear 24 meshing with the planetary gear 21 with respect to the sun gear 23 changes, and the drive shaft 11
And the center phase of the operating angle of the intake valve 1 changes.

Such a phase changing mechanism 20 has a relatively simple structure in which a planetary gear mechanism is provided at one end of the drive shaft 11, and can be easily applied to an existing engine. Since the center phase of the operating angle can be continuously changed, the degree of freedom in setting is high.

Referring again to FIG. 1, the variable valve apparatus includes an operating angle actuator 31 for rotating and holding the operating angle control shaft 12 of the operating angle changing mechanism 10 within a predetermined control range.
And a phase actuator 32 for rotating and holding the phase control shaft 28 of the phase changing mechanism 20 within a predetermined control range. Each of the actuators 31 and 32 is a hydraulic actuator that operates according to the supplied hydraulic pressure.
The hydraulic pressure supplied to each of the actuators 31 and 32 is switched and adjusted by an operating angle hydraulic device 33 and a phase hydraulic device 34 each having a hydraulic control valve and the like. An ECU (engine control unit) 35 performs general engine control such as fuel injection control based on a valve lift amount, a load, an engine speed, and oil temperature detected or estimated by various sensors. Control signals are output to the devices 33 and 34 to control the operation of the hydraulic devices 33 and 34.

FIG. 3 shows a preferred example of a specific setting of the intake valve opening / closing timing under each operating condition.
Represents the central phase of the operating angle of the intake valve. The settings are stored in advance in the memory of the ECU 35 in the form of a control map, for example.

In the idle range, IVC (intake valve closing timing)
Near the bottom dead center to increase the actual compression ratio, stabilize combustion, and delay the VC (intake valve opening timing) from the top dead center.
By setting a small lift and small operating angle, the flow velocity of intake air is increased. As a result, the fuel consumption and the combustion stability during idling can be significantly improved. Specifically, the center phase φ is set to the (most) retarded phase, and the intake operating angle is set to the (most)
The small operating angle is set.

In the R / L range (steady running range), the center phase φ is advanced to reduce the IVO
Is set to approximately the top dead center, and the IVC is accelerated to reduce the actual suction stroke. That is, the center phase φ is advanced mainly as compared with the above-mentioned idle range.

In the acceleration region, the center phase φ is larger than that in the R / L region.
Is further advanced and the operating angle is slightly increased,
The lVO is advanced before the top dead center, and the internal recirculation effect of mixing the residual gas into the air-fuel mixture is intended to further improve fuel efficiency.

In the fully open range, the setting is slightly different between a low speed and a high speed. However, in the above-mentioned acceleration range, the central phase φ is retarded with an increase in the number of rotations, and the operating angle is increased.
The main aim is to improve the maximum output.

As shown in FIG. 3, according to the contents of the control set in advance, for example, in the fully open range, the central phase φ is retarded with an increase in the operating angle. Do not become excessively large at the same time. Therefore,
As long as the control is performed well, there is no possibility that the intake valve 1 will interfere with the piston.

However, if the operating angle and the advance amount of the center phase become excessively large at the same time during a control failure or the like, there is a possibility that the intake valve 1 and the piston may interfere with each other. In order to completely eliminate the possibility of interference, in the present embodiment, both the operating angle changing mechanism 10 and the phase changing mechanism 20 are linked, and these changing mechanisms 10 and 20 are used.
A regulating mechanism 40 is provided for regulating the operation of each other continuously and continuously.

The structure and operation of the regulating mechanism 40 will be described with reference to FIGS. The regulating mechanism 40 continuously and mechanically regulates the change range of the center phase by the phase changing mechanism 20 in conjunction with the operating angle changing mechanism 10, and operates by the operating angle changing mechanism 10 in conjunction with the phase changing mechanism 20. It has the function of continuously and mechanically regulating the angle change range.

More specifically, the regulating mechanism 40 includes an operating angle control shaft 12 and a phase control shaft 28 which are disposed in parallel with each other.
A slider 41 that moves in the axial direction with the rotation of one of the control shafts (the phase control shaft 28 in this embodiment) is provided on the other control shaft, that is, the operation angle control shaft 12. A stopper pin 42 protruding radially from the outer periphery.

The slider 41 has a cylindrical nut portion 44 slidably screwed into a screw portion 43 formed on the outer periphery of the phase control shaft 28, and is rotatably and slidably mounted on the outer periphery of the operating angle control shaft 12. A substantially cylindrical limiter 45 to be fitted;
A connector 46 for integrally connecting the nut portion 44 and the limiter 45 is provided. The limiter 45 has a regulating cam 4 that can abut and engage with the stopper pin 42.
7 are formed. The restricting cam 47 is formed by one side edge of the limiter 45 which is appropriately notched, and extends in the first section 4 substantially parallel to the operating angle control shaft 12.
7a and a second section 47b bent from the first section 47a and appropriately curved. That is, the second section 47b is curved so that the contact position with the stopper pin 42 changes continuously according to the axial position of the slider 41.

In FIGS. 4 and 5, when the operating angle control shaft 12 is rotated in the direction of arrow Y1, the operating angle of the intake valve is increased, and when the phase control shaft 28 is rotated in the direction of arrow Y2, the intake air is controlled. As the center phase of the valve operating angle advances,
The slider 41 is set to move rightward in the figure. The maximum (initial) change range of the intake valve by the operating angle changing mechanism 10 is from the minimum operating angle Q1 to the maximum operating angle Q
The maximum (initial) change range of the center phase φ by the phase changing mechanism 20 is from the most retarded phase P1 to the most advanced phase P2. These change ranges are mechanically restricted by, for example, the formation range of the screw portion 43 and the like.

With this configuration, the stopper pin 4
The rotation range of the phase control shaft 28 to the advance angle side and the rotation range of the operation angle control shaft 12 to the large operation angle side The rotation ranges are mutually restricted, and the change ranges of the operating angle and the center phase of the intake valve are mutually restricted. As a result, the shift to the region α on the larger operating angle side or the advanced angle side than the regulation line L is mechanically prohibited.

More specifically, as shown in FIG. 4, when the intermediate operating angle and the center phase are set, the stopper pin 42
Is turned to the large operation angle side (arrow Y1) in the second section 47.
b is limited to a position (reference numeral R1 in FIG. 6)
By this time, the change range of the operating angle to the large operating angle side is mechanically limited by the operating angle Q3. That is, the actual operating angle change range is limited from the minimum operating angle Q1 to the above operating angle Q3. Further, the advance side of the slider 41 (the right side in the figure)
The range of movement to the second section 47b is the stopper pin 42
Is limited to the position (R1) where the center phase is advanced, and the range in which the center phase is advanced to the advance side is limited by the phase P3 at this time. That is, the actual phase change range is limited from the most retarded phase P1 to the above-described phase P3.

As shown in FIG. 5, when the center phase is largely advanced, the range of rotation of the stopper pin 42 toward the large operating angle is in contact with the first section 47a (reference numeral R2 in FIG. 6). And by this time the operating angle Q4,
The range in which the operating angle is changed to the large operating angle side is limited. on the other hand,
Since the movement of the slider 41 is not restricted, the center phase can be changed from the most retarded phase P1 to the most advanced phase P2.

As described above, as the operating angle increases, the regulation amount on the advanced side of the center phase continuously increases, and as the center phase increases, the regulation amount on the large operation angle side of the operating angle continuously increases. So that the regulating cam 47, especially the second
The profile of the section 47b is set.

According to the present embodiment as described above, the change to the region α having a large operating angle and a large advance angle is mechanically prohibited by the regulating mechanism 40. Possible troubles of interference between the intake valve 1 and the piston can be completely eliminated, and the reliability is excellent.

In other words, the regulation range α is
The range substantially corresponds to a range in which the intake valve and the piston may interfere with each other, and the operating angle and the center phase can be freely set in all regions except the range α. Therefore, it is possible to ensure the maximum degree of freedom in setting the operating angle and the center phase φ while reliably avoiding the interference between the intake valve and the piston.

FIGS. 7 to 10 show a regulating mechanism 50 of a variable valve operating apparatus according to a second embodiment of the present invention. As in the first embodiment, the operating angle changing mechanism 10 is provided on the intake valve side.
(See FIG. 1) and a phase changing mechanism 20 are applied.
Hereinafter, portions different from the above-described first embodiment will be described, and redundant description will be appropriately omitted.

In the second embodiment, the regulation mechanism 50 for regulating the change range of the operating angle and the center phase of the intake valve mutually and continuously is changed by the operating angle changing mechanism 10 to change the operating angle of the cylinder head and the like. First displaced relative to the engine body
The projection 51 as a movable part, the intake-side gear 52 as a second movable part displaced with respect to the engine main body due to the change of the center phase by the phase changing mechanism 20, and the support shaft 53 fixed to the engine main body rotate It has a lever 54 that is freely supported, one end of which can contact the cam surface 51 a of the projection 51, and the other end of which can contact the end surface 52 a of the intake gear 52.

The projection 51 integrally projects radially outward from the outer periphery of the rear end of the operating angle control shaft 12 of the operating angle changing mechanism 10 and has a helically curved band shape. . The rear surface of the protrusion 51 forms a cam surface 51a.

The intake side gear 52 is externally slidably and rotatably fitted to the rear end of the intake drive shaft 11 of the operating angle changing mechanism 10 via a ball screw 55.
It is connected to an exhaust camshaft 58 via an exhaust gear 56 and an intermediate gear 57. This exhaust camshaft 58
Has a fixed cam 59 for driving an exhaust valve, rotates in synchronization with a crankshaft via a pulley or a sprocket (not shown), and extends in the cylinder row direction in parallel with the intake drive shaft 11. are doing. This exhaust camshaft 5
An exhaust-side gear 56 is fixed to the rear end of the gear 8, and the exhaust-side gear 56 and the intake-side gear 52 are set to have the same number of teeth. An intermediate gear 57 meshes with both the exhaust side gear 56 and the intake side gear 52.

The spring 60 and the plunger 61 elastically urge one end of the lever 54 in the direction in which it comes into contact with the end face 52a of the intake gear 52. Thus, one end of the lever 54 is always kept pressed against the end face 52a of the intake gear 52.

The rotatable range of the lever 54 is regulated by the projection 51 and the intake gear 52. That is, in FIG. 7, the rotation range of the lever 54 in the counterclockwise direction is regulated by the protrusion 51, and the rotation range of the lever 54 in the clockwise direction is regulated by the intake gear 52.

For example, as shown in FIG.
When the rotational phase of the intake drive shaft 11 is advanced with respect to the rotational phase of the crankshaft in order to advance the center phase of the intake valve by 0, the drive shaft 11 rotates in synchronization with the crankshaft. It is relatively advanced with respect to the camshaft 58. On the other hand, the intake gear 52 always rotates at the same speed as the exhaust camshaft 58 via the exhaust gear 56 and the intermediate gear 57. Therefore, the amount of advance of the drive shaft 11 with respect to the exhaust camshaft 58 is equal to the intake gear 52.
Rotates relative to the drive shaft 11, and with this rotation, the intake-side gear 52 slides in the axial direction of the drive shaft 11 to the advance side (rear side in this embodiment). With the sliding operation of the intake-side gear 52, the clockwise rotatable range of the lever 54 is reduced. Here, the rotatable range of the operating angle control shaft 12 to the large operating angle side is determined by the protrusion 51.
Is restricted to a position where the cam surface 51a of the lever 54 comes into contact with the other end of the lever 54, so that the rotatable range of the operating angle control shaft 12 toward the large operating angle is also reduced. As described above, as the center phase is advanced by the phase changing mechanism 20, the changeable range of the operating angle to the large operating angle side by the operating angle changing mechanism 10 is continuously reduced.

On the other hand, as shown in FIG. 10, when the center phase is retarded by the phase changing mechanism 20, the intake gear 52 moves to the retard side (front side), contrary to the above-described advance. , The clockwise rotatable range of the lever 54 is enlarged. As a result, the rotatable range of the operating angle control shaft 12 to the large operating angle side is expanded, and the changeable range of the operating angle to the large operating angle side by the operating angle changing mechanism 10 is continuously expanded.

The same applies when the operating angle is changed by the operating angle changing mechanism 10. When the operating angle control shaft 12 is turned to the large operating angle side, the rotatable range of the lever 54 in the counterclockwise direction is reduced. The slidable range of the intake-side gear 52 to the advance side is reduced, and the changeable range of the center phase by the phase changing mechanism 20 to the advance side is reduced.

As described above, according to the present embodiment, the protrusion 5
The operating angle of the intake valve and its center phase can be mutually and continuously regulated by the regulating mechanism 50 having a relatively simple configuration mainly composed of the intake gear 52 and the lever 54. In particular, the rotatable range in one direction of the lever 54 is
With the simple configuration of the cam surface 51a formed on the projection 51, it is possible to continuously regulate the cam surface 51a.

The spring 60 and the plunger 61
As a result, the lever 54 is elastically biased, so that the followability of the lever 54 to the intake gear 52 (or the protrusion 51) is good, and the operation response is excellent.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a variable valve operating device for an internal combustion engine according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing a phase changing mechanism of the variable valve device.

FIG. 3 is a characteristic diagram showing opening / closing timing of an intake valve according to engine operating conditions.

FIG. 4 is an operation explanatory view showing a regulating mechanism of the embodiment.

FIG. 5 is an operation explanatory view showing the regulating mechanism of the embodiment.

FIG. 6 is a characteristic diagram showing a change range of an operating angle and a center phase of the intake valve according to the embodiment.

FIG. 7 is a plan view showing a regulating mechanism of a variable valve apparatus according to a second embodiment of the present invention.

FIG. 8 is a front view showing the regulating mechanism of FIG. 7;

FIG. 9 is an explanatory diagram showing an aspect at the time of phase advance according to the second embodiment.

FIG. 10 is an explanatory diagram showing an aspect at the time of phase retardation according to the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Intake valve 10 ... Operating angle changing mechanism 12 ... Operating angle control axis 20 ... Phase changing mechanism 28 ... Phase control axis 40 ... Restriction mechanism 41 ... Slider 42 ... Stopper pin 44 ... Nut part 45 ... Limiter 46 ... Connector 47 ... Restriction cam

 ──────────────────────────────────────────────────続 き Continued from the front page (72) Inventor Tsuneyasu Nohara 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan Motor Co., Ltd. (72) Inventor Yoshihiko Yamada 1370 Onna, Atsugi-shi, Kanagawa Pref. F term (reference) 3G016 AA06 AA19 BA19 BA22 BA30 BA33 BA34 BA36 BA39 BB21 CA04 CA06 CA08 CA10 CA16 CA22 CA25 CA31 CA47 CA52 DA03 DA08 DA22 DA23 GA00 3G018 AB05 AB07 AB17 BA02 BA17 BA19 BA32 CA02 CA04 CA07 CA13 CA19 DA03 DA04 DA09 DA DA19 DA21 DA29 DA30 DA76 EA02 EA11 EA17 EA22 EA31 EA32 EA33 FA01 FA06 FA07 GA02 GA22 GA39

Claims (10)

[Claims] 1. A variable valve operating system for an internal combustion engine, comprising: an operating angle changing mechanism for changing an operating angle of an intake valve or an exhaust valve; and a phase changing mechanism for changing a center phase of the operating angle. A variable valve actuation device for an internal combustion engine, comprising a regulating mechanism that is linked to both the changing mechanism and the phase changing mechanism and that regulates the operation of the operating angle changing mechanism and the phase changing mechanism mutually and continuously. . 2. A variable valve apparatus applied to an intake valve, wherein the regulating mechanism regulates a large operating angle side of the operating angle and regulates an advanced angle side of the center phase. The variable valve train for an internal combustion engine according to claim 1. 3. The regulation mechanism continuously changes the regulation amount of the center phase in accordance with a change in the operation angle by the operation angle changing mechanism, and in accordance with a change in the center phase by the phase change mechanism. 3. The variable valve operating device for an internal combustion engine according to claim 1, wherein the regulated amount of the operating angle is continuously changed. 4. An operating angle control axis and a phase control axis disposed in parallel with each other, the operating angle is changed by rotating the operating angle control axis, and the center is controlled by rotating the phase control axis. The regulating mechanism includes a slider that moves in the axial direction with rotation of one of the operating angle control axis and the phase control axis, and a stopper pin provided on the other control axis. The variable valve train for an internal combustion engine according to any one of claims 1 to 3, wherein the slider is provided with a regulating cam that engages with the stopper pin. 5. A nut portion in which the slider is slidably screwed around the outer periphery of the one control shaft, a limiter which is rotatably and slidably fitted on the outer periphery of the other control shaft, and these nut portions. The variable valve train for an internal combustion engine according to claim 4, further comprising: a connector that integrally connects the limiter and a limiter, wherein the restricting cam is formed by an edge of the limiter. 6. A drive shaft to which rotational power is transmitted from a crankshaft, a drive eccentric cam provided eccentrically to the drive shaft, and a rotatably fitted externally to the drive eccentric cam. A first link, a control cam provided eccentrically to the operating angle control shaft, a rocker arm rotatably fitted to the control cam and having one end connected to the first link; The swinging cam that is swingably provided and drives the intake valve or the exhaust valve, and a second link connected to the other end of the rocker arm and the swinging cam. 6. The variable valve train for an internal combustion engine according to 4 or 5. 7. The phase change mechanism includes a sun gear that rotates in synchronization with a crankshaft, a coaxial shaft disposed around the sun gear, and a camshaft that drives an intake valve or an exhaust valve or integrated with the drive shaft. A ring gear that rotates, a planetary gear that meshes with the outer periphery of the sun gear and the inner periphery of the ring gear, a carrier that rotatably supports the planetary gear, and a carrier that is provided on the phase control shaft and is provided on the outer periphery of the carrier. And a phase control gear that meshes with the carrier. By rotating the phase control shaft, the carrier rotates around the sun gear, and the planetary gear revolves around the sun gear. 7. The variable valve train for an internal combustion engine according to any one of 6. 8. A first displacement mechanism in which said regulating mechanism is displaced with respect to an engine body in accordance with a change of an operation angle by said operation angle changing mechanism.
A movable portion, a second movable portion that is displaced with respect to the engine main body in accordance with the change of the center phase by the phase changing mechanism, and is rotatably supported by the engine main body, one end of which can abut the first movable portion;
A lever whose other end can abut on the second movable portion, wherein the first movable portion or the second movable portion is displaced in accordance with one of the operation angle and the center phase, and 2. The rotatable range changes, and the other changeable range of the operating angle and the center phase changes.
The variable valve operating device for an internal combustion engine according to any one of claims 1 to 3. 9. The variable valve operating apparatus for an internal combustion engine according to claim 8, further comprising: urging means for urging the lever in a direction in which the lever comes into contact with the first movable portion or the second movable portion. 10. The first movable portion is a helical projection projecting from the outer periphery of an operating angle control shaft that is rotated when the operating angle is changed, and the first movable portion contacts one end of the lever. The variable valve train for an internal combustion engine according to claim 8 or 9, wherein a contactable cam surface is formed.