WO2007052363A1

WO2007052363A1 - Valve drive mechanism for four-cycle internal combustion engine

Info

Publication number: WO2007052363A1
Application number: PCT/JP2005/020394
Authority: WO
Inventors: Zensi Isikawa
Original assignee: Zensi Isikawa
Priority date: 2005-10-31
Filing date: 2005-10-31
Publication date: 2007-05-10

Abstract

A connection shaft (1) is supported at a cylinder head member (7) by a shaft (6) via a support arm (5) so as to be in parallel to a camshaft (3). The connection shaft (1) is pivotable together with the support arm (5) about the shaft (6) supported at the cylinder head member (7). One end of a second rocker arm (19) is pivotally supported by the connection shaft (1). At the other end of the second rocker arm (19) are coaxially supported a roller cam follower (11) and a first rocker roller follower (9). A cam base circle (4) is made to be in contact with the roller cam follower (11), the first rocker roller follower (9) is made to be in contact with a back surface (10-5) facing the camshaft (3) side of the first rocker arm (10), and the axis of the roller cam follower (11) and the shaft (6) supporting the support arm (5) are coaxial with each other when a valve is closed. In a valve drive mechanism for a four-cycle internal combustion engine, the connection shaft (1) is pivoted about the shaft (6) by a drive mechanism to allow the amount of lift of the valve to be continuously variable.

Description

Valve mechanism of 4-cycle internal combustion engine

Technical field

The present invention belongs to a valve mechanism of a four-cycle internal combustion engine.

Background technology-.

In many conventional four-cycle internal combustion engines, the valve lift timing, lift time, and lift amount are fixed. In this case, the intake amount required by the engine is adjusted by a throttle valve or throttle valve. It was.

Light

Even with a valve mechanism with a variable mechanism, only the opening and closing timing of the valve that changes the phase of the camshaft can be changed according to the operating condition using multiple cams, especially the intake valve. The field 1

There was nothing that made the lift amount continuously variable.

Therefore, the intake air amount is adjusted by the stroke throttle valve as described above. In particular, the engine efficiency is increased because the bombing loss due to the restriction of the intake air occurs at low and medium loads, which is the practical operating range of automobiles. Significantly reduced fuel consumption and carbon dioxide production. Disclosure of the invention

According to the present invention, the lift amount of the valve can be made freely variable according to the operating state of the engine. In particular, by using the valve operating mechanism according to the present invention for the intake valve, the intake air amount can be adjusted only by the valve itself. It is intended to do.

As a result, the adjustment by the throttle valve can be made unnecessary, so that the loss due to the pumping loss at low and medium loads can be reduced.

In general, it is necessary to incorporate some mechanism and member into the conventional simple D0HC and S0HC mechanism to make the lift amount continuously variable. Decrease and increase of inertial mass lead to high-speed follow-up, reduced performance, and increased friction loss.

In order to solve the above-described problems, the present invention uses extremely simple and low-cost parts without using complicated members and shapes and many link mechanisms as members that move directly in each cycle.

As a result, an excessive increase in the inertial mass should be prevented and the high-speed tracking performance of the valve mechanism should not be reduced.

Also, maintain the rigidity of the valve mechanism by using a simple mechanism.

As a result, improving the efficiency of the engine will improve the fuel efficiency and reduce the amount of carbon dioxide generated. Means for solving this problem will be described below. The cylinder head member 7 in the vicinity of the back surface of the first necker arm 10, 10-1 is supported by the support arm mounting shaft 6, 6-1, which is positioned parallel to the cam shaft 3. , 7-1, the support arm mounting shafts 6 and 6-1 allow the support arms 5 and 5-1 to be pivoted around the ends of the support arms 5 and 5-1, respectively. 'The shaft center line L of the support arm mounting shafts 6 and 6-1 should pass through the sky adjacent to the rear surfaces 10-5 and 10-3 of the first neck arm 10 and 10-1 when the valve is closed.

Then, the other ends of the support arms 5 and 5-1 are coupled to the connection shaft 1 positioned in parallel with the support arm mounting shafts 6 and 6-1 respectively, and the support arm mounting shafts 6 and 6-1 are the center. Support arms 5, 5-1 and connecting shaft 1 can be rotated as a body.

A boss portion at one end of the second mouth arm 19 is pivotally supported on the connecting shaft 1 so as to be rotatable about the connecting shaft 1.

A roller cam follower parallel to the connecting shaft 1 is connected to the other end of the second rocker arm 19 at the same distance as the distance from the shaft center of the support arm mounting shafts 6 and 6-1 to the shaft center of the connecting shaft 1. 11 and the smaller-diameter first rocking force per bite follower 9, 9- 1 are concentrically supported in the vicinity so that each can rotate freely.

With the valve closed, the cam base circle 4 is brought into contact with the roller cam follower 11, and the first rocker roller followers 9, 9-1 are in contact with the back surfaces of the first rocker arms 10, 10-1, respectively. At this time, the shaft center of the roller cam follower 11 and the first opening car roller follower 9, 9-1 and the support arm mounting shaft 6, 6-1 should be on the same axis.

Then, male screws 16 and female screws 15 are used as a drive mechanism for rotating the support arms 5, 5-1 and the connecting shaft 1 around the support arm mounting shafts 6 and 6-1. A support arm boss connecting the connecting shaft 1 is pivotally supported by a shaft 14 at a right angle to the connecting shaft 1, and a male screw 16 is screwed into the female screw 15.

The male screw 16 is pivotally supported by a control motor 23 so that the male screw 16 can be moved in and out of the female screw 15, thereby enabling the connecting shaft 1 to be rotated.

The control motor 23 is pivotally connected to the engine member 20 in a swingable manner.

With the above configuration, by driving the control motor 23 according to the operating state of the engine, the connecting shaft 1 is rotated about the support arm mounting shafts 6 and 6-1, so that Move the center of rotation of the second necker arm 19 pivotally supported at one end.

As a result, the direction of movement of the roller cam follower 11 driven by the cam is changed, and the first rocker rollers 10 and 10-1 of the first rocker roller followers 9 and 9-1 supported on the same axis are pushed down. Increase or decrease the movement component in the direction.

As a result, the valve mechanism of a 4-cycle internal combustion engine that makes the valve lift variable continuously. The effects of the present invention will be described below. In particular, if the valve operating mechanism of the present invention is used for the intake valve of a premixing engine, the valve lift can be continuously changed. The intake amount necessary for adjustment can be adjusted only by opening and closing the valve itself.

As a result, the intake air amount can be adjusted without using the throttle valve that has been used in the past, and the engine output can be controlled.

In order to achieve the above object, the second rocker arm 19 is the only newly added member in the valve system that reciprocates or swings in each cycle.

Therefore, the purpose is achieved without making the inertial mass of the valve mechanism particularly large compared to the simple D0HC and S0HC types of conventional engines.

In addition, it is possible to increase the rigidity of the valve mechanism at low cost because only one simple second rocker arm 19 is added without using a complicated shape and many link mechanisms for the member that moves every cycle. I can do it.

In addition, since the change in the lift amount of the valve is continuous, there is no sound during operation and there is sufficient follow-up even during high-speed operation, and the friction loss is sufficiently small due to the use of a single-hole follower. is there.

Furthermore, if the camshaft phase variable mechanism, which is a known technology, is used in the valve operating mechanism according to the present invention, the valve opening / closing timing can be changed, so that the variable lift and variable timing of the valve are possible, and the effect is doubled. Is.

As described above, friction loss due to low and medium load bombing loss can be reduced without degrading high-speed performance, which contributes to the maintenance and improvement of the global environment, such as reduction of fuel consumption and reduction of carbon dioxide generation.

Brief Description of Drawings

FIG. 1 is a three-dimensional view showing the main part of the present invention and shows the first embodiment.

FIG. 2 is a three-dimensional view showing the main part of the present invention and shows a second embodiment.

FIG. 3 shows the second rocker arm 19-1, the roller-cam follower 11-1, the first mouth-kucker roller follower 9-2, and the mouth-roller cam follower single shaft in the embodiment of FIG. FIG. 3 is a cross-sectional view showing the relationship between the first throat arm 10-2 and the connecting shaft 1. FIG. 4 shows the second mouth-cker arm 19, the roller cam follower 11, the first mouth stopper, the roller one follower 1, 9-1, the roller cam follower shaft 8 and the first mouth stopper in the embodiment of FIG. It is a diagram showing the relationship with one arm 10, 10-1, and is a plan view cut in parallel with the connecting shaft 1. Fig. 5 shows the third embodiment in which the first rocker arm is a bucket-shaped tappet 30, 30-1, and the tappet roller followers 9-3, 9-4 and the top of the tappet 31, 31- 1 is a cross-sectional view cut in parallel with a connecting shaft 1 showing a positional relationship in contact with 1. FIG.

FIG. 6 is an assembly view of an embodiment having a second mouth-packer arm 19-3 formed from an integral member in which the tape follower 9-6 does not rotate in the fourth embodiment.

FIG. 7 is a three-dimensional view of the embodiment shown in FIG.

FIG. 8 is a side view of the embodiment shown in FIG. FIG. 9 shows a cam follower and a tape follower 1-9, which is a single cam tapet follower 9-7, which is formed of a single, hollow member for lightening. 19-4 The assembly drawing of the 5th Example which has this.

FIG. 10 is a side view of the embodiment shown in FIG.

FIG. 11 is a cross-sectional view showing the positional relationship of the holding spring 18-1 provided between the support arms 5, 5-1 and the second rocker arm 19-4. -.

FIG. 12 is an assembly drawing of the sixth embodiment in which the outer diameter of the cam follower 11-3 is smaller than the outer diameter of the tappet followers 9-5 and 9-8.

FIG. 13 is a side view of the embodiment shown in FIG.

Fig. 14 is a sectional view showing the positional relationship between the cam follower 11-3 and the tappet followers 9-5, 9-8.

FIG. 15 is a view as seen from the axial direction of the camshaft 3 in the embodiment shown in FIG. 1. FIG. 15 is a side view showing the positions of the connecting shaft 1 and the second necker arm 19 in a low load or idle state. 5-1 are not shown.

FIG. 16 is a side view showing a state in which, in the positional relationship of FIG. 15, the cam is operated, the second mouth one arm 19 rotates around the connecting shaft 1 and the valve 13 is pushed down.

FIG. 17 is a view of the embodiment shown in FIG. 1 as seen from the axial direction of the camshaft 3. The connecting shaft 1 and the second mouth-packer arm 19 shown in FIG. 15 are centered on the support arm mounting shaft 6. Side view showing medium load at the position rotated in the F direction, support arms 5, 5-1 are not shown. FIG. 18 is a side view showing a state in which the cam operates in the positional relationship of FIG. 17 and the second stopper one arm 19 rotates around the connecting shaft 1 and the valve 13 is pushed down.

FIG. 19 is also a view of the embodiment shown in FIG. 1 as seen from the direction of the three camshafts. The connecting shaft 1 and the second mouth-packer arm 19 are further rotated in the F direction from the position shown in FIG. Side view showing heavy load at position, support arms 5, 5-1 are not shown.

FIG. 20 is a side view showing a state in which the cam operates in the positional relationship of FIG. 19, the second mouth one arm 19 rotates around the connecting shaft 1 and the valve 13 is pushed down.

FIG. 21 is a side view showing the geometric operation of the connecting shaft 1, the roller cam follower 11, the second necker arm 19 and the first necker arm 10 at low load.

FIG. 22 is a side view showing a geometric operation at medium load under the same configuration as FIG. 21.

FIG. 23 is a side view showing the geometric operation during medium load when the valve is closed under the same configuration as FIG.

FIG. 24 is a side view showing a geometric operation under a high load with the same configuration as FIG. Explanation of reference numerals in the drawings

1 is the connecting shaft 2 is the cam crest 3 is the cam shaft

4 is the cam base circle 5, 5-1 is the support arm

6, 6-1 is the support arm mounting shaft 7, 7-1 is the cylinder head member

8, 8-1, 8-2, 8-3, 8-4 is a roller cam follower single axis

9, 9-1, 9-2 is the first rocker roller Maolo

9-3, 9-4, 9-5, 9-8 are tappet mouth followers

9-6 is a tappet follower 9-7 is a tappet follower

10, 10-1 is the first rocker arm 10-2 is the T-shaped first rocker arm

12, 12-1 is the valve spring 11, 11-1 11-2, 11-3 is the roller cam follower

13, 13-1 is the valve 10-3, 10-4, 10-5 is the back of the first actuator arm 12, the shaft 23 is the control motor 14, the shaft

14-1 is bracket 15, female thread 16 is male thread 17, 17-1 is set pin 18, 18-1 is holding spring

19, 19-1, 19-2, -3, 19-4, 19-5 are the second mouth arm

20 is the engine member 21, the control circuit 22 is the accelerator 25, 25-1 is the first rocker shaft 30, 30 ■ 1 is the bucket-type tape 31, 31-1 is the tape The top L and L-1 are the same axis as the support arm mounting shaft A is the valve rib amount at low load B is the valve lift amount at medium load

C is the valve lift at high load

R is the rotation direction of the connecting shaft 1 on the low load side F is the rotation direction of the connecting shaft 1 on the high load side

X is the extension line of the top surface of the tappet 31

Y is a straight line that is parallel to the straight line X and passes through the axis L of the mouthpiece Larmor follower 11

Z is a straight line passing through the axis of camshaft 3 and the axis L of roller cam follower 11 '

X-1 is the back surface of the first rocker arm 10-5 and is an extension of the rolling surface

Y-1 is a straight line parallel to X-1 and passing through the axis L of the roller cam follower 11.

Z-1 is a straight line passing through the axis L of the camshaft 3 and the mouth follower cam follower 11. BEST MODE FOR CARRYING OUT THE INVENTION

The best mode for carrying out the present invention will be described below with reference to examples.

Example 1 and FIG. 1 showing the main configuration of the present invention will be described. The back arm 10-5 of the valve pressing contact portion of the first necker arm 10 is supported by the support arm mounting shaft 6 positioned parallel to the cam shaft. 15, one end of the support arm 5 is pivotally supported by a cylinder head member 7 adjacent to the cylinder head member 7 by the support arm mounting shaft 6 so as to be rotatable.

The support arm 6-1 also supports the cylinder head member 7-1 in the vicinity of the back surface 10-3 of the first rocker arm 10-1 by the support arm with the shaft 6-1 in the same positional relationship as above. Arm 5-1 is pivotally supported by one end.

The support arm mounting shafts 6 and 6-1 should be aligned with the axis center line L. When the valve is closed, it is close to the valve pressing part of the first rocker arm 10 and 10-1, and to the back part 10-5 and KK. Pass through the nearby sky.

Then, the other end portion of the support arm 5 is coupled to the connecting shaft 1 positioned in parallel with the support arm mounting shaft 6.

Similarly, connect the other end of the support arm 5-1 to the connecting shaft 1.

In this case, the support arms 5 and 5-1 and the connecting shaft 1 can be rotatably supported. However, in this embodiment, they are fixed and connected to ensure rigidity.

The support arms 5 and 5-1, and the connection shaft 1 are centered around the support arm mounting shafts 6 and 6-1.

-The body can be rotated.

In the connecting shaft 1 supported by the supporting arm 5 and the supporting arm 5-1, the connecting shaft 1 between the supporting arm 5 and the supporting arm 5-1 has a boss portion at one end of the second mouth arm 19. The shaft is supported so as to be rotatable about the connecting shaft 1.

Then, a connecting shaft is connected to the other end of the second rocker arm 19 branched into a fork shape having the same distance as the distance from the shaft center of the support arm mounting shaft 6 and 6-1 to the shaft center of the connecting shaft 1. In parallel with 1, a single roller cam follower shaft 8 is supported by a single roller cam follower shaft 8 so that it can rotate freely.

The cam base circle 4 is brought into contact with the roller cam follower 11 when the valve is closed.

The positional relationship between the roller cam follower 11 and the camshaft 3 is as shown in FIG. 15 at the time of low lift, at the time of middle lift shown in FIG. 17, and at the time of high lift shown in FIG. When the camshaft 3 rotates and the cam crest 2 operates to push the roller cam follower 11, it is necessary to operate smoothly without applying excessive force to the force shaft 3, roller cam follower 11 and connecting shaft 1.

For that purpose, when the first rocker arm 10 is used as shown in FIG. 17, the extension line X-1 of the first rocker arm back surface 10-5 which is the pressing surface of the roller-cam follower 11 is used. The small angle formed by the straight line Y-1 passing through the axis L of the straight cam follower 11 in parallel with the straight line Z-1 passing through the axis of the camshaft 3 and the axis of the roller cam follower 11 is 60 The camshaft 3 may be positioned so that it is about 30 degrees from about 30 degrees, but in the embodiment shown in Fig. 17, it is set to 47 degrees.

In the vicinity of the roller cam follower 11, a first rocker roller follower 9 having a smaller diameter than the roller cam follower 11 is rotatably supported by being coaxially supported. The Carro-Roller-Follower 9 is brought into contact with the back surface 10-5 facing the camshaft side in the vicinity of the valve pressing contact part of the first necker arm 10.

Since the roller follower 9 rolls back and forth on the rear surface 10-5 of the first mouth arm, it needs to be a flat surface, a gentle convex surface, or a gentle concave surface, but in this embodiment it is a flat surface. .

Similarly, a first rocker roller follower 9-1 having the same shape as the first rocker roller follower 9 is provided on the opposite side of the first rocker mouth follower 9 adjacent to the lower cam follower 11. Roller, cam follower, and 11 are coaxially supported to be rotatable.

Then, when the valve is closed, the first rocker port one follower 9-1 is brought into contact with the back surface 10-3 facing the camshaft side in the vicinity of the valve pressing portion of the first rocker arm 10-1.

In this state when the valve is closed, the axis of the roller cam follower 11 and the first rocker port one follower 9 and 9-1 and the axis of the support arm mounting shafts 6 and 6-1 are on the same axis. Be on L. 'And, each boss part that is connected to the connecting shaft 1 of the support arms 5 and 5-1 is provided with fixing pins 17-1 and 17 fixed respectively, along the curved surface of the boss part of the holding spring 18 Enclose the bent ends by hooking them onto the retaining pins 17-1 and 17 respectively.

The central part of the holding spring 18 is pressed against the arm part facing the first mouther arms 10 and 10-1 of the second mouther arm 19, and the roller cam follower 11 is caused by the reaction force. Always press against the force base circle 4.

Two brackets 14-1 are installed on the boss on the opposite side of the support arm on the boss supporting the connecting shaft 1 of the support arm 5-1.

A female screw 15 is pivotally supported by the shaft 14 at a position perpendicular to the connecting shaft between the brackets 14-1, and a male screw 16 is screwed into the female screw 15 for insertion.

The male screw 16 is shaft-coupled so that it can be driven by a control motor 23, and the male screw 16 can be moved in and out of the female screw 15, and the control motor 23 is pivotally supported on the engine member 20 by the shaft 12 and can swing.

The control motor 23 receives the amount of squeezing of the accelerator pedal 22, the squeezing speed, the position, etc. via the control circuit 21, and performs forward rotation, reverse rotation, stop position holding, etc. Bobo motor or stepping motor and associated control circuit are used. In the configuration as described above, the connecting shaft is connected by rotating the supporting arms 5 and 5-1 around the supporting arm mounting shafts 6 and 6-1 according to the operation amount of the accelerator pedal 22 Rotate 1

Naturally, the second rocker arm 19 connected to the connecting shaft 1 also rotates around the axis of the roller cam follower 11 concentric with the axis of the support arm mounting shafts 6 and 6-1.

As a result, the direction of movement of the roller cam follower 11 driven by the cam is changed, and the first rocker roller followers 9 and 9-1 supported by the coaxial shaft are pushed down. Increase or decrease the movement component in the direction.

ΙΪ1 As shown in 15, the connecting shaft 1 and the second locking force one arm 19 rotate in the R direction in the idle state where the accelerator pedal 22 is not swallowed or in a low load state, and the stand up It is the position.

If the cam acts at this position, the roller cam follower 11 will rotate about the connecting shaft 1 and the angle between the rotational direction and the component of motion in the direction to push down the valves 13 and 13-1 will be large. The amount of movement to push down 13 and 13-1 is small, resulting in a lift amount A as shown in Fig. 16.

FIG. 17 shows a state in which the connecting shaft 1 and the second necker arm 19 are rotated in the F direction where the rising is smaller than the position shown in FIG.

When the force is actuated at this position, the mouth lull cam follower 11 rotates about the connecting shaft 1, and the angle formed by the rotation direction and the component force of movement in the direction of pushing down the valves 13 and 13-1 is the above figure. Since it is smaller than the case of '15, the amount of movement to push down the valves 13 and 13-1 becomes larger than that in the case of FIG. 15, and as a result, the lift amount B is as shown in FIG.

FIG. 19 shows a state in which the connecting shaft 1 and the second mouth-cker arm 19 are rotated in the F direction, which is smaller than the position shown in FIG.

When the force force is actuated at this position, the roller cam follower 11 rotates about the connecting shaft 1 and the angle formed by the rotation direction and the component force of movement in the direction of pushing down the valves 13 and 13-1 is the above figure. The amount of rotation of the roller cam follower 11 is transmitted as the amount of movement that pushes down the valves 13 and 13-1.

As a result, the lift amount C shown in FIG. 20 is obtained.

As described above, if the connecting shaft 1 is rotated in the F direction, according to the amount of rotation, most of the amount of movement of the roller cam follower 11 is transmitted as the amount of movement that pushes down the valve, and the lift of the valve Increase the amount.

Further, if the connecting shaft 1 is rotated in the R direction, the amount of movement of the rotary cam follower 11 is transmitted with less rotation according to the amount of rotation, and the amount of lift of the valve is transmitted. Decrease.

The rotation in the R direction and the F direction can be continuously changed. Next, a second embodiment shown in FIG. 2 will be described. A roller-cam follower shaft 8-1 is attached to the other end portion of the second rocker arm 19-1 branched into a fork shape. -1 and the smaller diameter first mouthpiece, 1 roller, 1 follower, 9-2 are coaxially mounted in the vicinity, and each is rotatably supported.

The first rocker roller follower 9-2 is in contact with the back 10 ”4 facing the camshaft side of the first rocker arm 10-2 in the shape of a T-shaped lever.

The back surface 10-4 is a portion facing the cam shaft 3 side of the first necker arm 10-2 member between the first necker shaft and the valve pressing portion.

The operation is the same as in the first embodiment.

The third embodiment shown in FIG. 5 will be described. The direct-pressed bucket-shaped tapets 30 and 30-1 are used without using the first rocker arm.

At the other end of the second rocker arm 19-2 branched into a fork, a roller cam follower shaft 8-2 is connected to a mouth roller cam follower 11 1 2 and a tapet roller follower 9-3, 9-4. And are pivotally supported coaxially in the vicinity.

The tappet roller followers 9 3 and 9-4 are in contact with the top portions 31 and 31-1 of the tappets 30 and 30-1, respectively, when the valve is closed.

When the second rocker arm 19-2 is rotated about the connecting shaft 1 by the operation of the cam, the tapet roller one follower 9-3, 9-4 is connected to the tapet 30, 30-1. The top 31, 31-1 can be pushed down while rolling.

In each of the embodiments shown in Figs. 5, 8, 9, and 13 where bucket-type tappets 30 and 30-1 are used instead of the first rocker arm, it is parallel to the extension X of the top 31 of the tappet. The small angle formed by the straight line Y passing through the axis L of the roller cam follower 11 and the straight line Z passing through the axis L of the camshaft 3 and the axis L of the roller cam follower 11 is about 60 degrees as before. The camshaft 3 may be positioned so that it is about 30 degrees from the angle, but in the embodiment shown in Fig. 8, it is set to 43.5 degrees.

The principle of operation at that time is the same as that of the first embodiment.

The first rocker roller follower and the tapet roller one follower have the same function and the same position. However, for the sake of explanation, the first rocker roller follower is the one that contacts the first mouth roller arm. We named the tapet roller follower the one that is close to the tapet.

Also, the reason why the cam tappet follower is named 9-7 is that even if it is a single member, its function differs depending on the part. Industrial applicability

The valve operating mechanism of a four-cycle internal combustion engine according to the present invention is a premixing represented by a gasoline engine. It is highly likely to be used for a valve operating mechanism that drives an intake valve of an engine.

In particular, if the valve operating mechanism of the present invention is used for the intake valve of a premixing engine, the valve lift can be changed continuously, so that the amount of intake required for engine operation and output adjustment can be reduced. It can be adjusted only by orchid closure. Also, it can be applied to any cylinder arrangement such as single cylinder, in-line type, horizontally opposed type, V type, H type, W type, X type, star type, etc.

As a result, the friction loss due to the bombing loss at low and medium loads can be reduced without degrading the high-speed performance, which contributes to the maintenance and improvement of the global environment such as the reduction of fuel consumption and the generation of carbon dioxide.

Claims

.The scope of the claims

1 With the support arm mounting shaft located in parallel with the cam shaft, the support arm is attached to the cylinder head member so that the shaft center line passes through the sky adjacent to the back of the first necker arm when the valve is closed. The shaft is pivoted by supporting one end of the support arm.

The other end of the support arm is coupled to a connection shaft positioned in parallel with the support arm mounting shaft, and the support arm and the connection shaft can be rotated together around the support arm mounting shaft.

One end of the second mouth-packer arm is pivotally supported on the connecting shaft so that the connecting shaft can rotate around the connecting shaft. Then, the roller cam follower and the first opening are connected to the other end of the second rocker arm in parallel with the connecting shaft so as to have the same distance as the distance from the axis of the support arm mounting shaft to the connecting shaft. Rahora follower is supported in the vicinity and concentrically supported.

In the state when the valve is closed, the cam base circle is brought into contact with the roller one cam follower, and the first mouth car follower follower is brought into contact with the back of the first mouth cam arm. The shaft center of the one-kucker roller / follower and the shaft center of the support arm mounting shaft are on the same shaft center line.

By rotating the connecting shaft around the support arm mounting shaft in the above configuration, the center of rotation of the second mouth-supporting arm that pivotally supports one end of the connecting shaft is moved.

As a result, the movement direction of the first mouth follower follower in contact with the back surface of the first mouth carer is changed, and the movement component force in the direction of pushing down the first mouth knocker arm is increased or decreased. A valve mechanism for a 4-cycle internal combustion engine that attempts to make the lift variable.

2. The valve operating mechanism for a four-cycle internal combustion engine according to claim 1, wherein the two-roller cam follower is a cam follower formed of an integral member that does not rotate.

3. The valve operating mechanism for a four-stroke internal combustion engine according to claim 1, wherein the first mouth follower roller follower is a first mouth follower made of an integral member that does not rotate.

4. The 4-cycle according to claim 1, wherein the first rocker arm is replaced with a direct-pressing bucket-type tapet, and the top of the taptet is in contact with the tapet roller former. Valve mechanism for internal combustion engine.

5. The valve operating mechanism for a four-stroke internal combustion engine according to claim 4, wherein the tappet roller follower is a tappet follower composed of an integral member that does not rotate.