JP4180011B2 - Variable valve operating device for internal combustion engine - Google Patents

Description

  The present invention relates to a variable valve operating apparatus for an internal combustion engine that can vary the drive phase of an intake or exhaust valve.

  Engines (internal combustion engines) installed in automobiles are equipped with variable valve systems for reasons such as engine exhaust gas countermeasures and fuel efficiency reduction, and the intake and exhaust valve phases ( The opening / closing timing is changed.

  Such a variable valve device has a reciprocating cam structure in which the phase of the cam formed on the camshaft is temporarily replaced with a reciprocating cam in which a base circle section and a lift section are continuous. Many of the same structures employ a rocker arm mechanism that changes the ratio of the base circle section and lift section replaced with a reciprocating cam, and the ratio is changed according to the driving state of the vehicle ( For example, see Patent Document 1).

  By the way, in an engine, in order to improve output characteristics, multiple valves are used, and in many cases, two intake valves are used.

  In a variable valve operating device mounted on an engine having two intake valves, the two intake valves must be opened and closed with high accuracy.

Therefore, in a reciprocating cam type variable valve operating device mounted on a multi-valve engine, a reciprocating cam structure or a rocker arm mechanism can be individually mounted on the cylinder head for each intake valve to change the phase of the intake valve. (For example, refer to Patent Document 1).
Japanese Patent No. 3245492

  However, the variable valve device as disclosed in Patent Document 1 has a structure in which a reciprocating cam or a rocker arm mechanism is incorporated in a cylinder head for each intake valve, and therefore, the number of parts tends to increase and the size tends to increase.

  Accordingly, an object of the present invention is to provide a variable valve operating apparatus for an internal combustion engine that is capable of varying the phases of a plurality of valves while preventing the occurrence of an uneven load with a compact structure.

In order to achieve the above object, the rocker arm mechanism driven by a cam formed on the camshaft to open and close the intake or exhaust valve is supported by the rocker shaft so as to be swingable. Alternatively, a first arm that can drive the exhaust valve, a second arm that is driven by a cam and swings about the rocker shaft side as a fulcrum, and a support shaft disposed in the vicinity of the rocker shaft is swingably provided. The position of contact between the cam and the third arm that drives the first arm by changing the phase of the cam by the posture change caused by the movement of the fulcrum of the second arm in response to the displacement of the two arms is displaced forward and backward in the moving direction of the cam. After constructing a variable valve structure that varies the phase of the cam by a structure having a variable mechanism that displaces the fulcrum of the second arm on the rocker shaft side, Arms are arranged in parallel in the axial direction of the rocker shaft is formed in a bifurcated shape with a pair of rocker arms piece having a first wall portion and a second wall portion for transmitting the displacement to the intake or exhaust valve, said first A contact between the wall and the end of the second wall opposite to the valve has an abutment that contacts the third arm, and the second arm extends toward the rocker shaft and extends toward the rocker shaft. The third arm is formed in a substantially L shape having a fulcrum arm portion that is swingably fitted to a fulcrum, and a relay arm portion that extends toward the third arm and transmits displacement to the third arm. Has a transmission surface portion that contacts the abutment of the first arm to drive the first arm, and the fulcrum, the second arm, and the third arm are in the axial direction two of the rocker shaft. Interposed between the first wall and the second wall It is the displacement of the cam, through the second arm and the third arm between the first and second wall portions, and employs a configuration transmitted to the first wall and the second wall portion.

The invention according to claim 2 further so that in addition to the above objects, the continuously variable valve timing and lift amount of the valve of the valve in addition timing substantially aligned opening timing is performed, the transmission surface, the A converter that changes a distance from the center of the support shaft; and the fulcrum (pin member) is provided on the rocker shaft between the first wall and the second wall, and the variable mechanism includes the rocker shaft The third arm moves the first arm by changing the distance from the support shaft to the transmission surface portion by changing the posture of the second arm caused by the displacement of the contact position. The cam phase transmitted to the valve continuously changes with the valve lift amount of the intake or exhaust valve.

  According to the first aspect of the present invention, the phases of the plurality of valves can be varied by a simple single rocker arm mechanism in which the first to third arms are combined.

  Therefore, the variable valve gear can be made compact. Moreover, since the load applied to the plurality of valves is evenly transmitted to the first and second wall portions of the third arm that conveys the displacement to each valve, the phase of the plurality of valves can be varied while suppressing the occurrence of an uneven load. And stable and reliable phase control.

  According to the second aspect of the present invention, in addition to the above effects, there is an effect that the cam phase can be continuously varied and the valve lift amount can be continuously varied while the valve opening timings are substantially aligned.

[One Embodiment]
Hereinafter, the present invention will be described based on an embodiment shown in FIGS.

  FIG. 1 shows a sectional view of a cylinder head 1 of an internal combustion engine, for example, a reciprocating gasoline engine in which a plurality of cylinders are arranged in series. A combustion chamber 2 is formed on the lower surface of the cylinder head 1 along the longitudinal direction according to the arrangement of the cylinders. For example, two (a pair) of intake ports 3 and exhaust ports 4 (only one side is shown) are provided for each combustion chamber 2. Further, an intake valve 5 (configured by a reciprocating valve) for opening and closing the intake port 3 and an exhaust valve 6 (configured by a reciprocating valve) for opening and closing the exhaust port 4 are assembled to the upper portion of the cylinder head 1. ing. Note that the plurality of intake valves 5 and the plurality of exhaust valves 6 are each of a normally closed type that is urged by a valve spring 7 in the closing direction. Further, a valve operating system for driving a plurality of intake valves 5 and a plurality of exhaust valves 6, for example, an SOHC valve operating system 8 is mounted on the cylinder head 1.

  The valve system 8 will be described. Reference numeral 10 denotes a camshaft disposed on the head of the combustion chamber 2 so as to be rotatable in the longitudinal direction of the cylinder head 1, and 11 denotes an upper one side (cylinder head width) sandwiching the camshaft 10. A rotatable intake-side rocker shaft 12 disposed substantially parallel to the camshaft 10 on one side of the direction, and an exhaust-side rocker shaft 12 disposed substantially parallel to the camshaft 10 on the opposite side; Reference numeral 13 denotes a support shaft (corresponding to the support shaft of the present application) disposed in the vicinity of the rocker shaft 10, for example, at an upper point between the rocker shaft 11 and the rocker shaft 12, substantially parallel to the camshaft 10. The camshaft 10 is a component that is rotationally driven along the direction of the arrow in FIG. 1 by the crank output of the engine. The camshaft 10 is formed with an intake cam 15 and an exhaust cam 16 for each combustion chamber 2. Specifically, the intake cam 15 is formed at a position in the center of the head of the combustion chamber 2, and the exhaust cam 16 is formed on both sides of the intake cam 15 (shown in FIG. 2).

  Among these, the rocker shaft 12 on the exhaust side is provided with a rocker arm 18 (only one side is shown) for driving the exhaust valve 6 for each exhaust cam 16 so as to be rotatable. The intake-side rocker shaft 11 is provided with a rocker arm mechanism 19 that drives a plurality of (a pair of) intake valves 5 together for each intake cam 16. The rotation of the camshaft 10 causes a predetermined combustion cycle. The intake valve 5 and the exhaust valve 6 are opened and closed according to (for example, four cycles of an intake stroke, a compression stroke, an explosion stroke, and an exhaust stroke).

  The intake side rocker arm mechanism 19 is provided with a variable valve gear 20. 2 is a plan view of a rocker arm mechanism 19 constituting the variable valve operating apparatus 20, and FIG. 3 is an exploded perspective view of the rocker arm mechanism 19. As shown in FIG.

  The variable valve device 20 will be described. A rocker arm mechanism 19 constituting the device 20 includes a rocker arm 25 (supporting the first arm) supported on the rocker shaft 11 so as to be swingable as shown in FIGS. And a center rocker arm 35 (corresponding to the second arm) driven by the intake cam 15 and a swing cam 45 (corresponding to the third arm) supported swingably on the support shaft 13. Is used.

  Of these, the rocker arm 25 has a bifurcated structure for transmitting displacement to a plurality (a pair) of intake valves 5 as shown in FIG. For example, the rocker arm 25 has a cylindrical rocker shaft support boss 26 in the center as shown in FIG. 4, and a drive portion that drives the intake valve 5, for example, an adjustment screw, is sandwiched between the bosses 26. A structure is used in which a pair of rocker arm pieces 29 having portions 27 are arranged in parallel, and a roller member 30 serving as an abutment member is rotatably sandwiched between the other end portions of the rocker arm pieces 29. Specifically, as shown in FIG. 4, the roller member 30 includes a rocker arm piece 29 arranged in parallel using a through hole 31, a short shaft 32, and a bearing module 33 formed at the other end of the rocker arm piece 29. It is assembled | attached rotatably between the other end parts. That is, the rocker arm 25 has a structure in which one rocker arm piece 29 forming the first wall portion of the present application and the other rocker arm piece 29 forming the second wall portion are arranged in the axial direction of the rocker shaft 11. . The rocker shaft support bosses 26 of the assembled rocker arm 25 are inserted into the rocker shaft 11 so as to be swingable, the roller member 30 is directed toward the center of the cylinder head 1, and the remaining adjustment screw portions 27a are respectively placed on the cylinder head. 1 is disposed at the upper end (valve stem end) of the intake valve 5 protruding from the upper portion of 1. In FIG. 4, reference numeral 34 denotes a clip for fixing the short shaft 32 to the rocker arm piece 29.

  Further, as shown in FIGS. 1 and 3, the center rocker arm 35 includes a rolling contact that rolls in contact with the cam surface of the intake cam 15, for example, a cam follower 36, and a frame-shaped holder portion that rotatably supports the cam follower 36. An approximately L-shaped member with 37 is used. Specifically, the center rocker arm 35 is centered on the cam follower 36, the relay arm portion 38 extending in a column shape upward from the holder portion 37, specifically between the rocker shaft 11 and the support shaft 13, and the holder portion 37. A flat fulcrum arm portion 39 extending from the side portion to the lower side of the rocker shaft portion 11 a passing between the pair of rocker arm pieces 39 is formed in an L shape. At the tip (upper end) of the relay arm portion 38, an inclined surface 40 is formed as a relay portion that transmits displacement to the swing cam 45, for example, so that the rocker shaft 11 side is low and the support shaft 13 side is high. is there. The remaining tip of the fulcrum arm 39 is supported by, for example, the rocker shaft portion 11a. For this support, for example, as shown in FIGS. 1 and 3, a pin member 41 having a spherical portion 41 a formed at the lower end portion is provided on the rocker shaft portion 11 a toward the distal end portion of the fulcrum arm 39. A structure that is screwed and fixed (for example, fixed with a nut 41b) so as to penetrate (diameter direction) from the upper side to the lower side of the shaft portion 11a, and the pin end protruding from the rocker shaft portion 11a is supported by the fulcrum arm portion 39. Is used. In other words, on the upper surface of the distal end portion of the fulcrum arm portion 39, a spherical receiving portion 42 that is movably fitted to the spherical portion 41a protruding from the rocker shaft portion 11a is formed. As a result, when the cam follower 36 is driven by the intake cam 15, the center rocker arm 35 swings in the vertical direction around the rocker shaft 11 side, that is, the pivot portion where the spherical portion 41a and the receiving portion 42 are fitted. I have to do it. Further, for example, a control motor 43 (shown only in FIG. 3) is connected to the end of the rocker shaft 11 as a control actuator. 5 and FIG. 6 is rotationally displaced in a range from a posture in which the pin member 41 is arranged in the vertical direction to a posture inclined at an angle of approximately 45 ° in the camshaft rotation direction shown in FIG. 7 and FIG. I can do it. That is, the fulcrum moving mechanism 44 (corresponding to the variable mechanism of the present application) constituted by the control motor 43 and the pivot support structure causes the fulcrum on the rocker shaft 11 side of the center rocker arm 35 to be in a direction intersecting the axial direction of the shaft 11. It can be moved. Then, using the positional shift of the center rocker arm 35 caused by this movement, the rolling contact position (contact position) of the cam follower 36 with respect to the intake cam 15 is variable, that is, the intake cam as shown in FIGS. 15 can be displaced back and forth in the rotational direction.

  On the other hand, as shown in FIGS. 1 to 3, the swing cam 45 has a cylindrical boss portion 46 that is rotatably inserted into the support shaft 13, and the boss portion 46 faces the roller member 30 (the rocker arm 25). And an arm portion 47 extending in the direction and a displacement receiving portion 48 formed in the lower portion of the arm portion 47. Among these, a cam surface 49 extending in the vertical direction, for example, is formed at the tip of the arm portion 47 as a transmission surface portion that transmits displacement to the rocker arm 25. The cam surface 49 is in rolling contact with the outer peripheral surface of the roller member 30 of the rocker arm 25. Further, for example, as shown in FIG. 3, the displacement receiving portion 48 is formed with a recessed portion 51 in a lower surface portion of the lower portion of the arm portion 47 that is directly above the camshaft 10, and the shaft 10 is placed in the recessed portion 51. , 11 and a structure in which a short shaft 52 is rotatably provided. More specifically, a concave portion 53 is formed in the lower portion of the short shaft 52 exposed from the opening portion of the concave portion 51, and the distal end portion of the relay arm portion 38 (center rocker arm 35) slides in the concave portion 53. Insert freely. A flat receiving surface 53 a that slidably receives the inclined surface 40 is formed on the bottom surface of the recess 53. As a result, when the swing cam 45 receives the swing of the center rocker arm 35, the support shaft 13 serves as a fulcrum, the recess 53 serves as an action point where a load from the center rocker arm 35 acts, and the cam surface 49 drives the rocker arm 25. As a power point, it is structured to swing periodically. Using the swing displacement of the swing cam 45, when the cam follower 36 is displaced from a predetermined position of the intake cam 15 in the advance direction and the retard direction (the center rocker arm 35 is displaced forward and backward in the movement direction of the intake cam 15). The phase of the intake cam 15 is made variable.

  From the combination of these parts, a rocker arm mechanism 19 in which a center rocker arm 35 and a swing cam 35 are interposed between a pair of rocker arm pieces 29 formed in a bifurcated shape is constructed. From there, it is transmitted to the intake valve 5 through the rocker arm piece 29.

  Further, the cam surface 49 is formed with a curved surface (the conversion portion of the present application) in which the distance from the center of the support shaft 13 changes. For example, as shown in FIG. 1, the upper side of the cam surface 49 is formed by a base circle section α, that is, an arc surface centered on the axis of the support shaft 13 as shown in FIG. The lower part is formed by a lift section β, that is, an arc surface opposite to the arc and the arc surface opposite to the arc, for example, an arc surface similar to the cam shape of the lift area of the intake cam 15. A curved surface as an interval is used. When the cam follower 36 is displaced from the predetermined position of the intake cam 14 in the advance direction by the cam surface 49 (the fulcrum position of the center rocker arm 35 is displaced), the region of the cam surface 49 with which the roller member 30 contacts, more specifically, the roller member 30. The ratio of the base circle section α and the lift section β where the roads come and go is changed. As a result of the change in the ratio that is accompanied by the change in the advance direction, the opening / closing timing of the intake valve 5 is continuously varied while aligning the valve opening timing, and at the same time, the valve lift amount of the intake valve 5 is continuously varied. It is.

  In FIG. 1, 54 is a pusher for energizing the intake cam and the center rocker arm 35 and the swing arm 45 in close contact with each other, and 55 is an ignition plug for igniting the air-fuel mixture in the combustion chamber 2. Show.

  Next, the operation of the variable valve operating apparatus 20 configured as described above will be described.

  First, the movement of the rocker arm mechanism 19 accompanying opening and closing of the intake valve 5 will be described. It is assumed that the camshaft 10 is now rotating (in the direction of the arrow).

  At this time, the cam follower 36 of the center rocker arm 35 receives the intake cam 15 disposed between the rocker arm pieces 29 and is driven in accordance with the cam profile of the cam 15. Then, the center rocker arm 35 is swung in the vertical direction with the pivot portion on the rocker shaft 11 side as a fulcrum. Then, this swinging displacement is transmitted to the swing cam 45 directly above the center rocker arm 35.

  Here, one end portion of the swing cam 45 is swingably supported by the support shaft 13, and the other end portion is in rolling contact with the roller member 30 of the rocker arm 25. From this state, the inclined surface 40 at the tip of the relay arm 38 is received by the receiving surface 53a of the short shaft 52 at the lower part. Therefore, the cam surface 49 of the swing cam 45 swings in the vertical direction while repeating the behavior of being pushed up and lowered while sliding between the inclined surface 40 and the receiving surface 53a.

  At this time, since the roller member 30 between the pair of rocker arm pieces 29 is in rolling contact with the cam surface 49, the roller member 30 is periodically pressed by the swinging cam surface 49. By this pressing, the pair of rocker arm pieces 29 are driven with the rocker shaft 11 as a fulcrum, and a plurality (a pair) of intake valves 5 are opened and closed together.

  During such operation, the rocker shaft 11 is rotated by the control motor 43, and the fulcrum position of the center rocker arm 35 is positioned at a point where the maximum valve lift amount is secured, for example. Then, the cam follower 36 of the center rocker arm 35 is displaced on the intake cam 15 by the same positioning, and the cam surface 49 of the swing cam 45 is positioned in an attitude close to vertical.

  Then, the cam surface 49 has a posture that provides the maximum valve lift amount, that is, the region (ratio) where the roller member 30 crosses is the narrowest base circle section α shown in FIG. 5 and the longest lift section β shown in FIG. Set to As a result, as shown in the diagram A1 in FIG. 9, the intake valve 5 is the largest valve according to the rocker arm piece 29 driven by the cam surface portion formed by the narrow base circle section α and the longest lift section β. The lift is opened and closed at a desired opening / closing timing.

  On the other hand, when the phase of the intake cam 15 is varied, as shown in FIGS. 7 and 8, the operation of the control motor 43 causes the rocker shaft 11 to be secured at a position where the maximum valve lift amount is secured (FIGS. 5 and 6). The pin member 41 is rotated clockwise from the inner pin member 41 position. Thereby, the pivot part (fulcrum position) of the center rocker arm 35 is shifted to the camshaft 10 side.

  Here, in the center rocker arm 35, the portion that transmits displacement to the swing arm 45 is formed by the inclined surface 40 of the relay arm portion 38 and the short shaft 52 that slidably receives the inclined surface 40, and the intake cam 15 Since the receiving portion is formed by the cam follower 36 that is in rolling contact with the intake cam 15, when the position shift is received, the center rocker arm 35 is moved so that the rolling position of the cam follower 36 moves in the advance direction of the intake cam 15. Displace (shift) to advance. Due to the change of the rolling contact position, the valve opening timing of the cam phase to be varied is controlled to be advanced according to the variable amount.

  The center rocker arm 35 changes to a posture in which the cam surface 45 of the swing cam 45 faces downward as shown in FIGS. 7 and 8 due to the displacement (displacement) of the fulcrum. Along with this inclination, the region of the cam surface 49 where the roller member 30 passes is changed to a region having a ratio in which the base circle section α is gradually longer and the lift section β is gradually shortened. Then, the cam profile of the variable cam surface 49 is transmitted to the rocker arm 18 through the roller member 30 to drive the pair of rocker arm pieces 29 while advancing the valve opening timing. As a result, the opening / closing timing of the intake valve 5 is the minimum valve obtained when the pin member 41 tilts to 45 ° from the maximum valve lift amount A1 as shown in FIG. 9 by the movement of the fulcrum position of the center rocker arm 35. Up to the lift amount A7, variable control is continuously performed while maintaining the valve opening timing from substantially the same valve opening timing as at the time of maximum valve lift. 7 and 8 show a state when the minimum valve lift amount A7 is set.

  The structure in which the cam phase is varied in this manner is between the pair of rocker arm pieces 29 and 29 for driving the valve (between the arrows X to X in FIG. 2 and FIG. 3), although the plurality of intake valves 5 are driven. In addition, the simple rocker arm mechanism 19 having the center rocker arm 35 and the swing cam 45 interposed therebetween can be realized, and the variable valve operating apparatus 20 can be made compact. In addition, since the load applied to the plurality of intake valves 5 is evenly transmitted to the rocker arm pieces 29 and 29 through the intermediate portions (roller portions 30) of the rocker arm pieces 29 and 29, the occurrence of an offset load that impairs the variable cam phase is generated. The opening / closing timing of the plurality of intake valves 5 can be varied with high accuracy.

  In addition, the cam lift transmitted to the rocker arm pieces 29 and 29 by changing the distance from the support shaft 13 to the cam surface 49 due to the displacement of the fulcrum position of the center rocker arm 35 is varied in the swing cam 45. In addition, since the continuously changing structure is used, the opening / closing timing of the intake valve 5 and the valve lift amount can be varied continuously by changing the valve closing timing larger than the valve opening timing. In particular, the control of the valve lift amount and the opening / closing timing by greatly changing the valve closing timing makes it possible to inhale intake air into the cylinder while suppressing loss, and exhibits an excellent effect of reducing pumping loss. Further, even if the phase variable device is used in combination with the present invention, the phase variable amount can be small, so that a variable response delay does not occur, and sufficient fuel consumption can be improved.

  The present invention is not limited to the above-described embodiment, and various modifications may be made without departing from the spirit of the present invention. For example, in the above-described embodiment, the present invention is applied to the rocker arm mechanism of the intake valve. However, the present invention is not limited to this, and may be applied to the rocker arm mechanism of the exhaust valve. In one embodiment, the present invention is applied to an engine of an SOHC valve system (a structure in which an intake valve and an exhaust valve are driven by a single camshaft). However, the present invention is not limited to this, and a DOHC valve system (cam The present invention may be applied to an engine having a structure in which the shaft is dedicated to the intake side and the exhaust side.

Sectional drawing which shows the variable valve apparatus which concerns on one Embodiment of this invention with the cylinder head which mounts the apparatus. The top view of the variable valve apparatus. The disassembled perspective view of the variable valve operating apparatus. The disassembled perspective view which shows the structure of the rocker arm (1st arm) of the variable valve operating apparatus. Sectional drawing which shows a state when the contact part of a rocker arm exists in the base circle area of the cam surface at the time of the maximum valve lift control of the variable valve apparatus. Sectional drawing which shows a state when the contact part of a rocker arm exists in the lift area of a cam surface similarly. Sectional drawing which shows a state when the contact part of a rocker arm exists in the lift area of the cam surface at the time of the minimum valve lift control of the variable valve apparatus. Sectional drawing which shows a state when the contact part of a rocker arm exists in the lift area of a cam surface similarly. The diagram which shows the performance of the variable valve operating apparatus.

Explanation of symbols

  5 ... intake valve, 6 ... exhaust valve, 11 ... intake side rocker shaft, 13 ... support shaft (support shaft), 19 ... rocker arm mechanism, 20 ... variable valve gear, 25 ... rocker arm (first arm), 30 ... Roller member (contact element), 35 ... center rocker arm (second arm), 29 ... rocker arm piece (first wall portion, second wall portion), 44 ... fulcrum moving mechanism (variable mechanism), 45 ... swing cam (first) 3 arms), 49... Cam surface (transmission surface portion), α, β... Base circle section, lift section (conversion section).

Claims (2)

A camshaft rotatably provided in the internal combustion engine;
A rocker shaft disposed in parallel with the camshaft and provided in the internal combustion engine;
A variable valve operating apparatus for an internal combustion engine having a rocker arm mechanism that is driven by a cam formed on the camshaft to open and close an intake or exhaust valve;
The rocker arm mechanism is
A first arm supported swingably on the rocker shaft and capable of driving an intake or exhaust valve;
A second arm that abuts on the cam and is driven by the cam and swings about the rocker shaft side;
The cam is provided on a support shaft disposed in the vicinity of the rocker shaft so as to be swingable. The displacement of the second arm causes a change in the posture of the second arm caused by movement of the fulcrum of the second arm. A third arm that drives the first arm with a variable phase;
A variable mechanism for displacing the fulcrum of the second arm on the rocker shaft side in order to displace the abutting position with the cam in the longitudinal direction of the cam;
The first arm, the are arranged in parallel in the axial direction of the rocker shaft, formed bifurcated and includes a pair of rocker arms pieces Yes a first wall portion for transmitting the displacement to the intake or exhaust valve and a second wall portion An abutment that abuts against the third arm between the end of the first wall and the second wall opposite to the valve;
The second arm extends to the rocker shaft side and is pivotally fitted to the rocker shaft side fulcrum, and extends to the third arm side to transmit displacement to the third arm. Formed in a substantially L shape having a relay arm portion,
The third arm has a transmission surface portion in contact with the contact of the first arm to drive the first arm,
The fulcrum, the second arm, and the third arm are interposed between the first wall portion and the second wall portion in two axial directions of the rocker shaft,
The internal combustion engine, wherein the displacement of the cam is transmitted to the first wall portion and the second wall portion through the second arm and the third arm between the first and second wall portions. Variable valve gear. The transmission surface portion includes a conversion portion whose distance from the center of the support shaft changes,
The fulcrum (pin member) is provided on the rocker shaft between the first wall portion and the second wall portion,
The variable mechanism displaces the fulcrum by rotating the rocker shaft,
The third arm has a cam phase transmitted to the first arm by changing a distance from the support shaft to the transmission surface portion from a change in posture of the second arm caused by displacement of the contact position. 2. The variable valve operating apparatus for an internal combustion engine according to claim 1, wherein the variable valve operating apparatus is continuously variable together with a valve lift amount of an intake or exhaust valve.

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