JP2010242622A - Variable valve mechanism and internal combustion engine using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable valve mechanism performing variable control of a valve lift quantity with simplicity, light weight and low cost. <P>SOLUTION: A rotating cam 4 of the variable valve mechanism 1 has a pair of a fixed cam 4a and movable cam 4b. This pair of the fixed cam 4a and movable cam 4b moves together around a cam shaft 2 in a rotating direction, but in an axial direction of the cam shaft 2, the movable cam 4b is only movable and the space of each other is variable. When a roller 8 of a swing arm 7 is depressed by rotation of the rotating cam 4, the space of the pair of the fixed cam 4a and movable cam 4b of the rotating cam 4 is changed, so that a depression quantity of the roller 8 is changed, thus the valve lift quantity is changed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a variable valve mechanism and an internal combustion engine using the same, and more particularly, a variable valve mechanism capable of performing variable control of a valve lift amount at a simple, light weight and low price, and an internal combustion using the variable valve mechanism. It is about the institution.

  Various variable valve mechanisms have been introduced that continuously vary the phase and valve lift amount of the intake and exhaust valves in accordance with the operating state (rotation speed, load, etc.) of the internal combustion engine.

  9 to 11, the lift of the camshaft 60 is received by the roller arm 62 fixed to the control shaft 61 by a helical gear, and the arm 63 fixed by a spline is also used as the valve. Depress 64. When the control shaft 61 is moved in the axial direction, only the roller arm 62 is rotated along the helical gear and the relative angle with the arm 63 is changed, so that the valve lift is variable (see, for example, Patent Document 1 and Patent Document 2). .

  In this structure, two cylinders 63 and one roller arm 62 are attached to the control shaft 61 for each cylinder, and a shaft having a spline or a helical gear is provided on the inner side thereof. It has a triple structure with a shaft to be used. For this reason, there is a problem that the structure is complicated, the weight is increased, and the price is increased.

JP 2004-60497 A JP 2001-263015 A

  In order to solve the above-described problem, the present inventor has provided a control cam 72 between the rotary cam 70 and the swing arm 71 as shown in FIGS. 12 and 13, and a pair of control levers of the control arm 72. A configuration in which the valve lift amount dw is changed by changing the push-down amount of the roller 73 of the swing arm 71 by changing the interval between 72a and 72b is not publicly known.

  In this structure, the structure can be greatly simplified and reduced in weight as compared with the structures shown in FIGS. 9 to 11, and the price can be promoted. However, the control between the camshaft 74 and the swing arm 71 is possible. Since the arm 72 (a pair of control levers 72a and 72b) is disposed, there is a problem that an energy loss occurs due to the presence of the moving parts, and improvement in fuel consumption is hindered.

  An object of the present invention is to provide a variable valve mechanism that can perform variable control of a valve lift amount simply, lightweight, and at a low price.

  Another object of the present invention is to provide an internal combustion engine that can reduce exhaust gas, improve fuel efficiency, and is excellent in vehicle mountability.

  In order to achieve the above object, a variable valve mechanism according to the present invention is a variable valve mechanism that transmits a rotational torque of a camshaft that is rotationally driven by a crankshaft to a valve, and controls the opening and closing of the valve. A rotating cam provided on the camshaft, a control shaft provided at a position distant from the camshaft, and pivotally supported at a position distant from the camshaft and the control shaft so as to rotate the rotating cam. An interlocking swing arm; a roller that is rotatably supported by the swing arm; and a roller that contacts the rotating cam when the rotating cam rotates; and the valve connected to the swing arm, And a first cam and a second cam, wherein the first cam and the second cam are the camshaft. The camshaft is fixed in the rotational direction around the shaft, but the cam shaft is configured such that the interval between the camshafts is variable, and a groove that narrows toward the center of the roller is formed on the outer periphery of the roller. When the rotary cam contacts the groove, the amount of lift of the valve is changed by changing the amount of pressing of the roller according to the interval between the first cam and the second cam of the rotary cam. To change.

  In the above variable valve mechanism, the camshaft includes first camshafts and second camshafts arranged alternately along the axial direction, and the first cam rotates in the rotational direction and the axial direction. The second camshaft is fixed to the second camshaft, and the second cam is fixed in the rotational direction but movable in the axial direction. The control shaft is connected to the second cam, and is connected to moving means for moving the second cam in the axial direction, and the control shaft is moved by the moving means. When moved in the axial direction, the distance between the first cam and the second cam is changed by moving the second cam in the axial direction while the first cam remains fixed. That.

  Further, in the variable valve mechanism described above, a taper that fits into the groove of the roller is formed on the rotating cam on the contact side with the roller. According to this configuration, the roller can be smoothly pushed down by the rotating cam, and the friction between the rotating cam and the roller can be reduced, so that the fuel consumption of the internal combustion engine can be improved.

  In order to achieve the above object, an internal combustion engine of the present invention has the variable valve mechanism.

  According to the variable valve mechanism of the present invention, the valve lift amount can be variably controlled by adjusting the distance between the first and second cams of the rotary cam, so that the valve lift amount can be changed easily, lightly and at a low price. Control can be performed.

  Further, according to the internal combustion engine using the variable valve mechanism of the present invention, exhaust gas can be reduced and fuel consumption can be reduced by using the variable valve mechanism that can perform variable control of the valve lift amount. Can be improved. In particular, since no other moving member is interposed between the rotating cam and the swing arm, energy loss can be reduced as compared with a configuration in which another moving member is interposed between the rotating cam and the swing arm. As a result, fuel consumption can be improved.

  Further, according to the internal combustion engine using the variable valve mechanism of the present invention, since no other motion member is interposed between the rotating cam and the swing arm, another motion member is interposed between the rotating cam and the swing arm. Compared to an internal combustion engine using a variable valve mechanism, the overall height of the internal combustion engine can be kept low. As a result, the internal combustion engine is excellent in vehicle mountability.

It is a block diagram of the variable valve mechanism which is embodiment of this invention. It is sectional drawing of the II line | wire of FIG. It is the block diagram which showed the connection state of a moving means and a control shaft. It is a block diagram of the variable valve mechanism of FIG. 1 at the time of valve closing. It is a block diagram of the variable valve mechanism of FIG. 1 at the time of valve opening. It is sectional drawing which compared and showed the valve lift amount at the time of valve opening in each when the space | interval of a pair of cam of a variable valve mechanism was made into the minimum (left) and the maximum (right). It is sectional drawing of the location corresponding to the II line | wire of FIG. 1 of a variable valve mechanism when the space | interval of a pair of cam is set to the minimum. It is principal part sectional drawing of the engine carrying the variable valve mechanism of FIG. It is principal part sectional drawing of an example of the conventional variable valve mechanism. It is a principal part perspective view of the component of the variable valve mechanism of FIG. It is the principal part perspective view which fractured | ruptured and showed a part of component of FIG. It is a block diagram of the variable valve mechanism which this inventor examined. It is sectional drawing of the II-II line | wire of FIG.

  Hereinafter, a variable valve mechanism according to an embodiment of the present invention and an engine (internal combustion engine) using the same will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a configuration diagram of a variable valve mechanism according to the present embodiment, FIG. 2 is a cross-sectional view taken along line I-I in FIG. 1, and FIG. 3 shows a connection state between a moving means and a control shaft.

  The variable valve mechanism 1 according to the present embodiment is a mechanism that transmits the rotational torque of a camshaft 2 that is rotationally driven by a crankshaft of a vehicle engine to the valve 3 to control the opening and closing of the valve 3. In addition to the valve 3, the rotary cam 4, the control shaft 5, the swing arm 7, the roller 8, and the end pivot 9 are provided.

  As shown in FIG. 2, the camshaft 2 is pivotally supported in a rotatable state by a plurality of bearings 10 arranged along the axial direction at predetermined intervals. The camshaft 2 is divided for each bearing 10, and has a first camshaft 2a and a second camshaft 2b. The first cam shaft 2a and the second cam shaft 2b are alternately arranged along the axial direction. The first camshaft 2a is disposed at the position of the bearing 10, and the second camshaft 2b is disposed between the adjacent bearings 10 (first camshaft 2a).

  On the surface of the second camshaft 2b, a plurality of spline forming irregularities extending along the axial direction are alternately arranged along the outer peripheral direction of the shaft. The first camshaft 2a is welded and fixed firmly to both ends of the second camshaft 2b via a spline. As a result, the first camshaft 2a and the second camshaft 2b rotate together in the rotational direction about the axis. A timing gear 11 is joined and fixed to the outermost first camshaft 2a. The timing gear 11 transmits the rotational driving force from the crankshaft to the camshaft 2.

  The second camshaft 2a of the camshaft 2 is provided with a plurality of rotating cams 4 along its axial direction. A number of rotating cams 4 corresponding to the number of valves are installed between the bearings 10 adjacent to each other. A projecting portion (nose) 4s having a partly long radial distance from the center is formed on a part of the outer periphery of the rotating cam 4, and the entire cross-sectional shape of the rotating cam 4 perpendicular to the camshaft 2 is substantially oval. Is formed.

  As shown in FIG. 1, a swing arm 7 is pivotally supported at a position away from the camshaft 2 and the control shaft 5 so as to be swingable. The swinging motion of the swing arm 7 is interlocked with the rotational motion of the rotary cam 4. In the swing arm 7, a valve 3 is connected to one end side in the longitudinal direction, an end pivot 9 is connected to the other end side, and a roller 8 is rotatably supported between them.

  The valve 3 is a poppet valve and has a head portion 3a, a face portion 3b, a stem portion 3c, and a stem end portion 3d. Here, the valve 3 is closed, and the face portion 3b of the valve 3 is in contact with the valve guide 12 of the engine.

  As shown in FIG. 2, a V-shaped groove 8 a that narrows toward the center of the roller 8 is formed on the outer periphery of the roller 8. When the valve is opened, the rotary cam 4 contacts the surface of the groove 8a on the outer periphery of the roller 8. The swing arm 7 swings around the end pivot 9 as a fulcrum. When the hydraulic adjuster is incorporated in the end pivot 9, as shown in FIG. 2, the cylindrical surfaces at both axial ends of the rotating cam 4 are in contact with the roller 8, and the valve 3 does not lift. When the hydraulic adjuster is not used, a gap (gap) is provided between the cylindrical surface and the roller 8 by adjusting the height of the end pivot 9.

  By the way, in the variable valve mechanism 1 of the present embodiment, as shown in FIG. 2, the rotating cam 4 is a pair of cams, a fixed cam (first cam) 4a and a movable cam (second cam) 4b. It has. A taper portion 4c is formed on the outer periphery on the surface side of the rotating cam 4 constituted by the fixed cam 4a and the movable cam 4b. The tapered portion 4c is a portion that contacts the surface of the groove 8a on the outer periphery of the roller 8 when the valve is opened, and the pair of fixed cam 4a and movable cam 4b form a substantially V-shaped cross section. By providing such a tapered portion 4c, the roller 8 is pushed down so that the tapered portion 4s having a V-shaped section of the rotating cam 4 fits into the groove 8a having a V-shaped section of the roller 8 when the valve is opened. Pushing can be performed smoothly. For this reason, the friction between the rotating cam 4 and the roller 8 can be reduced. As a result, the fuel consumption of the engine can be improved.

  The fixed cam 4a is joined and firmly fixed to the second camshaft 2b by vibration welding via a spline on the surface of the second camshaft 2b. That is, the fixed cam 4a is fixed both in the rotational direction about the second camshaft 2b and in the axial direction (the direction indicated by the arrow P1 in FIG. 2). On the other hand, the movable cam 4b is also fixed in the rotational direction around the second camshaft 2b by a spline on the surface of the second camshaft 2b. For this reason, the pair of fixed cams 4a and movable cams 4b are fixed to each other with respect to the rotational direction around the camshaft 2, and move together without shifting their relative planar positions.

  However, the movable cam 4b is installed in a movable state in the axial direction of the second camshaft 2b by a spline on the surface of the second camshaft 2b. That is, by moving the movable cam 4b along the axial direction of the second cam shaft 2b, the fixed cam 4a remains fixed, so that the interval between the pair of fixed cams 4a and the movable cam 4b is changed to a desired interval. be able to.

  As shown in FIG. 2, the plurality of movable cams 4b between the bearings 10 adjacent to each other are joined by a connection pin 13, and are installed so as to be movable together along the axial direction of the second camshaft 2b. ing. The connection pin 13 is connected from one movable cam 4b to the other movable cam 4b through a through hole formed in the fixed cam 4a between the movable cams 4b. Further, it is preferable that the connection pins 13 are arranged so as to have a symmetrical relationship with each other at a position where at least two or more connection pins 13 sandwich the second camshaft 2b. Thereby, movement of a plurality of movable cams 4b can be made smooth.

  The movable cam 4 b is connected to the joint portion 14. The joint portion 14 is connected to the control shaft 5 via a slider 15. The control shaft 5 is provided along the axial direction of the camshaft 2 while being supported by the bearing 10 at a position away from the camshaft 2. The control shaft 5 is engaged with the bearing portion 10 via the screw structure portion 16 and is shown on the bearing 10 in a rotatable state. Thereby, the blurring at the time of movement of the control shaft 5 can be suppressed, and movement with high dimensional accuracy can be realized.

  Further, an extension portion 4d extending from the fixed cam 4a to the movable cam 4b opposite to the fixed cam 4a is joined to the fixed cam 4a between the movable cams 4b. The extending portion 4d has a function of restricting (stopping) the movement of the movable cam 4b. That is, when the control shaft 5 is moved too much when the operation is performed so as to increase the distance between the pair of fixed cams 4a and the movable cams 4b, the joint portion 14 and the slider 15 are large only if there is no extension portion 4d. A restraining force is applied, which causes deterioration and damage of the joint portion 14 and the slider 15. By providing the extended portion 4d, the movable cam 4b is prevented from excessively moving, and the extended portion 4d is also restrained and the restrained force applied to the joint portion 14 and the slider 15 can be reduced. Deterioration or damage of the slider 15 can be suppressed or prevented. Here, the axial length of the extending portion 4d is set so that the movable cam 4b stops just before the joint portion 14 side contacts the bearing 10 or just before contacting.

  The other end of the control shaft 5 is connected to a DC motor (moving means) 21 via a connection shaft 20 as shown in FIG.

  A hollow rotor coil 21b is accommodated in the housing 21a of the DC motor 21, and a stator magnet 21c is disposed on the outer periphery thereof. The worm gear portion of the rotating shaft 21d is accommodated in the hollow of the rotor coil 21b. The rotor coil 21b is electrically connected to an engine control device (not shown) through the brush 21e.

  A connecting shaft 20 is connected to the rotating shaft 21d of the DC motor 21, and the control shaft 5 is connected through this. That is, by converting the rotational operation of the rotating shaft 21d of the DC motor 21 into movement in the axial direction (direction indicated by arrow P1) by the worm gear portion, the control shaft 5 connected thereto is moved in the axial direction. The distance between the pair of fixed cam 4a and movable cam 4b is adjusted (changed).

  In the middle of the connecting shaft 20 in the axial direction, a tapered portion 20a is formed partially so that the diameter of the connecting shaft 20 gradually decreases along the axial direction, and the sensor 22 is disposed on the tapered portion 20a. . The sensor 22 is for detecting an actual stroke of the control shaft 5 in the axial direction, and is formed of, for example, a pickup coil disposed so as to surround the outer periphery of the tapered portion 20a.

  Next, the operation of the variable valve mechanism 1 of the present embodiment will be described with reference to FIGS. 4, 5 and 6. 4 shows the state of the variable valve mechanism 1 when the valve 3 is closed, FIG. 5 shows the state of the variable valve mechanism 1 when the valve 3 is opened, and FIG. 6 shows a pair of the variable valve mechanism 1. Sectional drawing which compared and showed the valve lift amount at the time of valve opening in each when the space | interval of this fixed cam 4a and movable cam 4b was made into the minimum (left of FIG. 6) and the maximum (right of FIG. 6) is shown. Yes. In FIGS. 4 and 5, the distance between the pair of fixed cam 4a and movable cam 4b is maximized. 4 and 5 show the center line and rotation coordinates of the camshaft 2.

  In the stage of FIG. 4, the protrusion 4 s of the rotating cam 4 is not in contact with the outer periphery of the roller 8. The vent 22 is closed, and the face 3b of the valve 3 is in contact with the valve guide 12 of the engine.

  Subsequently, as shown in FIGS. 5 and 6, when the rotating cam 4 is rotated counterclockwise in FIG. 5, the protrusion 4 s of the rotating cam 4 gradually comes into contact with the outer periphery of the roller 8, and the roller 8 is moved downward. Pushed to the side. At this time, the tapered portion 4 c having a V-shaped cross section of the rotating cam 4 comes into contact with the V-shaped groove 8 a on the outer periphery of the roller 8 and pushes down the roller 8. As a result, one end side of the swing arm 7 is lowered downward (closer to the engine body side), the valve 3 is also pushed down, the face portion 3b of the valve 3 is separated from the valve guide 12, and the vent 22 is opened. That is, in the variable valve mechanism 1 of the present embodiment, the rotating cam 4 directly pushes down the roller 8 and no other member is interposed between the rotating cam 4 and the roller 8.

  When the apex of the protrusion 4s of the rotating cam 4 comes into contact with the outer periphery of the roller 8, the valve lift amount becomes the largest. As shown in FIG. 5, the rotation angle of the rotating cam 4 at this time is α, and the valve lift is dmx. Here, since the distance between the pair of fixed cam 4a and movable cam 4b is maximized, the valve lift amount dmx is the maximum valve lift amount that can be set by the variable valve mechanism 1.

  Next, an operation of adjusting (changing) the valve lift amount by adjusting (changing) the distance between the pair of fixed cam 4a and movable cam 4b will be described with reference to FIGS. FIG. 7 shows a cross-sectional view of the variable valve mechanism 1 corresponding to the line II in FIG. 1 when the distance between the pair of fixed cam 4a and movable cam 4b is set to the minimum.

  First, as shown in FIG. 7, the control shaft 5 is moved in the axial direction (left direction shown by the arrow P2 in FIG. 7), and the movable cam 4b is brought close to the fixed cam 4a and brought into contact with the fixed cam 4a (fixed cam). 4a and the distance between the movable cam 4b is zero). As a result, the distance between the pair of fixed cams 4a and the movable cams 4b is made narrower than that in the right cases of FIGS. 2, 4, 5, and 6 to a minimum value.

  In this state, as shown in the left of FIG. 6, the rotary cam 4 is rotated, and the valve lift amount becomes maximum when the apex of the protrusion 4 s of the rotary cam 4 contacts the roller 8. At this time, the rotation angle of the rotary cam 4 is the same as that in FIG. 5, but the distance between the pair of fixed cam 4a and movable cam 4b is narrower than that in FIG. Changes in contact with the groove 8a of the roller 8, and the amount by which the tapered portion 4c pushes down the roller 8 is reduced. As a result, as shown on the left side of FIG. 6, the amount by which the roller 8 is pushed down can be reduced, so that the valve lift amount can be made smaller than the valve lift amount dmx in the case of FIGS. In the setting of FIG. 7, the distance between the pair of fixed cam 4 a and movable cam 4 b is minimized, so that the valve lift amount is the minimum valve lift amount that can be set by the variable valve mechanism 1. In addition, dz of FIG. 6 has shown the difference (lift amount of lift) of the lift amount when the space | interval of a pair of fixed cam 4a and movable cam 4b is changed from the minimum to the maximum. The lift amount can be arbitrarily changed depending on the shape of the protrusion 4s of the rotating cam 4.

  Thus, according to the variable valve mechanism 1 of the present embodiment, variable control of the valve lift amount can be performed by adjusting the distance between the pair of fixed cams 4a and movable cams 4b of the rotating cam 4. That is, since the valve lift amount can be variably controlled with a simple structure in which no other member for variable valve lift control is provided between the rotating cam 4 and the roller 8, it is simpler than the structure described with reference to FIGS. It is possible to perform variable control of the valve lift amount with light weight and low price.

  Next, a variable control method of the valve lift amount using the moving means will be described.

  During the operation of the vehicle, the engine control device continuously sends a control signal to the DC motor 21 so as to obtain a valve lift amount corresponding to the engine speed and the load. For example, the engine speed is acquired by communication from the control data of the fuel injection control device of the engine, and the load is acquired by, for example, an existing calculated value recorded in a ROM (Read Only Memory) of the control device. .

  In the DC motor 21, based on a control signal from the engine control device, the distance between the pair of fixed cams 4a and the movable cam 4b is suitable for the engine speed and load, that is, the valve lift amount is the engine speed. The control shaft 5 is moved so that the value is optimal for the load. At this time, the engine control device compares the actual movement amount of the control shaft 5 detected by the sensor 22 with the target movement amount, and if there is a deviation in the value, the control shaft is connected to the DC motor 21. A control signal for correcting the movement amount 5 is sent.

  Thus, according to the variable valve mechanism 1 of the present embodiment, the valve lift amount can be continuously set to an optimum value. Further, since the actual stroke value of the control shaft 5 is detected and the movement amount of the control shaft 5 (that is, the distance between the pair of fixed cam 4a and movable cam 4b) can be corrected based on the actual stroke value, the valve lift amount can be increased with high accuracy. Can be set.

  Next, FIG. 8 shows a cross-sectional view of a main part of the engine 25 on which the variable valve mechanism 1 is mounted.

  A piston 27 in the cylinder 26 of the engine 25 is connected to a crankshaft 29 through a connecting rod 28. The reciprocating motion of the piston 27 (up and down motion in FIG. 8) is converted into rotational motion by the crankshaft 29.

  Here, a case where the variable valve mechanism 1 is installed on the intake port 22a side of the engine 25 is illustrated. The combustion chamber 26a of the cylinder 26 is connected to the intake pipe 30a through the intake port 22a. On the other hand, a variable valve mechanism 31 of the prior art is installed on the exhaust port 22b side of the engine 25. The variable valve mechanism 31 of the prior art has a single configuration in which the rotating cam 4 does not have a pair of cams. The combustion chamber 26a is connected to the exhaust pipe 30b through the exhaust port 22b.

  The variable valve mechanism 1 of the present embodiment may be installed only on the exhaust port 22b side, or may be installed on both the intake port 22a side and the exhaust port 22b side. Reference numeral 32 denotes a valve spring that applies a closing force to the valve 3.

  According to the engine 25 of the present embodiment, by using the variable valve mechanism 1 of the present embodiment, the valve lift amount can be continuously set to the optimum value according to the state of the engine 25. Exhaust gas can be reduced, and power performance and fuel consumption can be improved.

  In particular, since no other motion member is interposed between the rotating cam 4 and the swing arm 7, energy loss is reduced compared to a configuration in which another motion member is interposed between the rotating cam 4 and the swing arm 7. it can. As a result, fuel consumption can be improved.

  Further, in the engine 25 of the present embodiment, since no other motion member is interposed between the rotating cam 4 and the swing arm 7, another motion member is interposed between the rotating cam 4 and the swing arm 7. Compared to the engine using the variable valve mechanism, the overall height of the engine 25 can be kept low. Thereby, it becomes the engine 25 excellent in vehicle mounting property.

  In the variable valve mechanism and the internal combustion engine using the same according to the present invention, the rotary cam of the variable valve mechanism includes a first cam and a second cam, and the first cam and the second cam are camshaft shafts. The center of the camshaft is fixed in the rotational direction, but the camshaft is configured so that the interval between the camshafts is variable, and a groove that narrows toward the center of the roller is formed on the outer periphery of the roller of the swing arm. When the rotating cam comes into contact with the groove, the valve lift amount is changed by changing the lift amount of the valve by changing the push-down amount of the roller according to the interval between the first cam and the second cam of the rotating cam. Can be continuously set to an optimum value in accordance with the state of the internal combustion engine, so that it can be used for a variable valve mechanism of an automobile engine and an automobile engine.

DESCRIPTION OF SYMBOLS 1 Variable valve mechanism 2 Cam shaft 2a 1st cam shaft 2b 2nd cam shaft 3 Valve 4 Rotating cam 4a Fixed cam (1st cam)
4b Movable cam (second cam)
4c Taper 5 Control shaft 7 Swing arm 8 Roller 8a Groove 21 DC motor (moving means)
25 engine (internal combustion engine)

Claims (4)

In the variable valve mechanism that transmits the rotational torque of the camshaft that is rotationally driven by the crankshaft to the valve and controls the opening and closing of the valve,
A rotating cam provided on the camshaft;
A control shaft provided at a position away from the camshaft;
A swing arm that is pivotally supported at a position distant from the cam shaft and the control shaft, and interlocks with a rotation operation of the rotary cam;
A roller that is rotatably supported by the swing arm, and that the rotating cam contacts when the rotating cam rotates;
The valve connected to the swing arm,
The rotating cam includes a first cam and a second cam,
The first cam and the second cam are fixed with respect to the rotation direction around the axis of the camshaft, but the distance between each other in the axial direction of the camshaft is variable.
A groove that narrows toward the center of the roller is formed on the outer periphery of the roller. When the rotating cam comes into contact with the groove, the first cam and the second cam of the rotating cam A variable valve mechanism that changes the lift amount of the valve by changing the push-down amount of the roller according to the interval. The camshaft has first camshafts and second camshafts arranged alternately along the axial direction,
The first cam is provided on the second camshaft in a fixed state with respect to the rotational direction and the axial direction;
The second cam is fixed to the rotational direction, but is provided on the second camshaft so as to be movable in the axial direction.
The control shaft is connected to the second cam and connected to moving means for moving the second cam in the axial direction;
When the control shaft is moved in the axial direction by the moving means, the first cam and the second cam are moved by moving the second cam in the axial direction while the first cam remains fixed. The variable valve mechanism according to claim 1, wherein the interval is changed.   The variable valve mechanism according to claim 1 or 2, wherein a taper that fits into the groove of the roller is formed on a contact side of the rotating cam with the roller.   An internal combustion engine having the variable valve mechanism according to claim 1, 2 or 3.

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