JP2009209750A - Variable valve gear for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To hold at an intermediate operating angle during engine stop in preparation for the next start of the engine. <P>SOLUTION: In a first variable valve mechanism continuously executing variable control of an operating angle, the operating angle is determined by changing a rotating position of a control shaft 32 by a hydraulic actuator 33. The actuator 33 includes a cylindrical cylinder 51 and a piston 54 connected to a rod 55. The position of the piston 54 is controlled by supply of hydraulic pressure to first and second hydraulic chambers 52, 53. The piston is apt to move to a small operating angle side due to valve lift reaction. A stopper pin 61 for biasing a stopper plate 67 in a protruding manner is provided as an intermediate stopper mechanism 60 at the end of the small operating angle side. The stopper pin 61 is projected by a coil spring when the hydraulic pressure drops during the engine stop so as to restrict the movement of the piston 54 so that the lift and the operating angle must not be the minimum. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a variable valve gear that can continuously change the operating angle of an intake valve or an exhaust valve of an internal combustion engine.

  In a gasoline engine, the intake air amount is generally controlled by controlling the opening of a throttle valve provided in the intake passage. As is well known, this type of system has a particularly small throttle valve opening. There is a problem that the pumping loss is large at low load. In contrast, attempts have been made to control the intake air amount without depending on the throttle valve by changing the opening / closing timing of the intake valve and the lift amount.

  Patent Document 1 was previously proposed by the present applicant. As a valve operating device for an intake valve, a variable valve operating device (lift) capable of simultaneously expanding and reducing the lift and operating angle of the intake valve simultaneously.・ Combining the variable operating angle mechanism with the second variable valve mechanism (variable phase mechanism) that continuously delays the position of the central angle of the operating angle, mainly opens and closes the intake valve according to the engine operating state. An intake air amount control device for an internal combustion engine that controls the intake air amount by changing the timing is disclosed.

Further, in Patent Document 2, a similar lift / operating angle variable mechanism uses an alternating torque that acts on the actuator side as a reaction force of the valve lift, and immediately after the engine stops, the control shaft naturally has the smallest lift / operation. A variable valve gear that is in an angular position is disclosed.
JP 2002-256905 A JP 2006-46228 A

  In the variable valve system as described above, since the reaction force of the valve lift acts in the direction of reducing the operating angle, the operating angle generally tends to be small when the internal combustion engine is stopped. For this reason, for example, if an attempt is made to include even a very small lift / operating angle in the control range in order to realize a small flow rate during idling, the operating angle becomes excessively small at the start, which may make starting difficult. In Patent Document 2, since the minimum lift / operating angle on the mechanism is given at the start, the minimum lift / operating angle cannot be set too small, and the control range of the lift / operating angle is narrowed. . In particular, when a hydraulic actuator is used as the actuator, it is difficult to change the valve lift characteristics simultaneously with the start of cranking, and it is likely to take a long time to start.

  The present invention has a control shaft whose rotational position is controlled by a linearly moving hydraulic actuator, the valve operating angle is continuously changed according to the rotational position of the control shaft, and the reaction force accompanying the valve lift Therefore, it is assumed that the hydraulic actuator has a variable valve system for an internal combustion engine that receives an urging force in the direction of reducing the operating angle.

  The hydraulic actuator is provided with an intermediate stopper mechanism that projects into the cylinder of the hydraulic actuator when the engine is stopped so that the reaction angle does not become the minimum operating angle when the engine is stopped, and the operating angle of the piston of the hydraulic actuator is reduced. Movement is restricted at an intermediate position.

  In one aspect, the intermediate stopper mechanism comprises a stopper pin that advances and retreats along the moving direction of the piston at the end of the hydraulic actuator on the small operating angle side, and in another aspect, the intermediate stopper mechanism is The stopper pin is provided on the side wall of the hydraulic actuator and moves forward and backward along a direction orthogonal to the moving direction of the piston.

  By these intermediate stopper mechanisms, the movement of the piston toward the direction of reducing the operating angle is limited, and the intermediate operating angle is maintained at a certain intermediate operating angle without becoming the minimum operating angle.

  According to the present invention, by restricting the movement of the piston in the direction of reducing the operating angle to the intermediate operating angle position by the intermediate stopper mechanism, the operating angle is not excessively reduced at the time of starting and the startability is improved. To do. In addition, the normal control range can be expanded to the small operating angle side, and the degree of freedom of control is increased.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an explanatory diagram showing a system configuration of an intake air amount control device for an internal combustion engine using a variable valve device according to the present invention. The internal combustion engine 1 has an intake valve 3 and an exhaust valve 4. In addition, as the valve operating mechanism of the intake valve 3, the variable valve operating apparatus according to the present invention, that is, the first variable valve operating mechanism (VEL) capable of continuously expanding and reducing the lift and operating angle of the intake valve 3 is provided. 5 and a phase variable mechanism capable of continuously delaying the central angle of the operating angle, that is, a second variable valve mechanism (VTC) 6. The intake passage 7 is provided with an electronically controlled throttle valve 2 whose opening degree is controlled by an actuator such as a motor. Here, the throttle valve 2 is used only for generating a slight negative pressure (for example, −50 mmHg) necessary for processing blow-by gas in the intake passage 7 and adjusting the intake air amount. Is basically performed by changing the valve lift characteristics of the intake valve 3 by the first and second variable valve mechanisms 5 and 6. That is, a substantial throttle-less operation that does not depend on the throttle valve opening for adjusting the intake air amount is realized. The first and second variable valve mechanisms 5 and 6 and the electronic control throttle valve 2 are controlled by the control unit 10.

  A fuel injection valve 8 is disposed in the intake passage 7, and an amount of fuel corresponding to the intake air amount adjusted by the intake valve 3 as described above is injected from the fuel injection valve 8. Accordingly, the output of the internal combustion engine 1 is controlled by adjusting the intake air amount by the first and second variable valve mechanisms 5 and 6.

  The control unit 10 includes an accelerator opening signal APO from an accelerator opening sensor 11 provided on an accelerator pedal operated by a driver, an engine rotation speed signal Ne from an engine rotation speed sensor 12, and an intake air amount sensor. The control unit 10 inputs the fuel injection amount, the ignition timing, the throttle valve opening, the operating angle target value, the center angle target value, etc. based on these signals. And the fuel injection valve 8, the spark plug 9, the throttle valve 2, the first and second variable valve mechanisms 5, 6, and the like are controlled. Also, a starter motor (not shown) is provided, and when starting the engine, predetermined start-up control including cranking is executed based on an input from a starter switch (key switch) (not shown).

  FIG. 2 is an explanatory diagram showing the configuration of the first and second variable valve mechanisms 5 and 6. The mechanical structure of the first variable valve mechanism 5 and the second variable valve mechanism 6 is known, and for example, has the same structure as the device described in Patent Document 1 described above. Therefore, only the outline will be described.

  The first variable valve mechanism 5 that variably controls the lift and operating angle includes a drive shaft 22 driven by a crankshaft of the internal combustion engine 1, a drive eccentric cam 23 fixed to the drive shaft 22, and a rotatably supported shaft. A control shaft 32, a rocker arm 26 swingably supported by a control eccentric cam 38 of the control shaft 32, and a swing cam 29 that contacts the tappet 30 of the intake valve 3. The eccentric cam 23 and the rocker arm 26 are linked by a link arm 24, and the rocker arm 26 and the swing cam 29 are linked by a link member 28.

  The rocker arm 26 is supported at its substantially central portion by the control eccentric cam 38 so as to be capable of swinging. The arm portion of the link arm 24 is linked to one end of the rocker arm 26 via a connecting pin 25. The upper end portion of the link member 28 is linked to the end portion via a connecting pin 27. The control eccentric cam 38 is eccentric from the axis of the control shaft 32, and accordingly, the rocking center of the rocker arm 26 changes according to the angular position of the control shaft 32.

  The swing cam 29 is rotatably supported by being fitted to the outer periphery of the drive shaft 22, and a lower end portion of the link member 28 is linked to an end portion extending laterally via a connecting pin 37. ing. On the lower surface of the swing cam 29, a base circle surface concentric with the drive shaft 22 and a cam surface extending in a predetermined curve from the base circle surface are continuously formed. These base circle surface and cam surface come into contact with the upper surface of the tappet 30 according to the swing position of the swing cam 29.

  The control shaft 32 is configured to rotate within a predetermined angle range by a lift / operating angle control actuator 33 provided at one end. As will be described later, the lift / operating angle control actuator 33 is a linear movement type hydraulic actuator that rotationally drives the control shaft 32 via a link mechanism, and is controlled by a control signal from the control unit 10. Is controlled through. Specifically, the rotation angle of the control shaft 32 is detected by the control shaft sensor 34, and feedback control is performed so that the target rotation angle corresponds to the target lift / operation angle.

  According to the first variable valve mechanism 5, the lift and operating angle of the intake valve 3 are continuously expanded and reduced simultaneously according to the rotational angle position of the control shaft 32. With the change in size, the opening timing and closing timing of the intake valve 3 change substantially symmetrically. Since the magnitude of the lift / operation angle is uniquely determined by the rotational position of the control shaft 32, the actual lift / operation angle at that time is indicated by the detected value of the control shaft sensor 34.

  On the other hand, the second variable valve mechanism 6 that variably controls the center angle is configured such that the sprocket 42 provided at the front end portion of the drive shaft 22 is relative to the sprocket 42 and the drive shaft 22 within a predetermined angle range. And a phase control actuator 43 that is rotated in an automatic manner. The sprocket 42 is linked to the crankshaft via a timing chain or timing belt (not shown). In the present embodiment, the phase control actuator 43 is a hydraulic rotary actuator, and is controlled by a control signal from the control unit 10 via a hydraulic control valve (not shown). The action of the phase control actuator 43 causes the sprocket 42 and the drive shaft 22 to rotate relative to each other, thereby delaying the lift center angle in the valve lift. That is, the lift characteristic curve itself does not change, and the whole advances or retards. This change can also be obtained continuously. The control state of the second variable valve mechanism 6 is detected by a drive shaft sensor 36 that responds to the rotational position of the drive shaft 22.

  FIG. 3 shows the valve lift characteristics of the intake valve 3 under typical operating conditions. As shown in the figure, in an extremely low load range such as an idle, the lift / operating angle is minimum and the central angle is The phase is the most retarded position. As a result, the closing time becomes the position immediately before the bottom dead center.

  In a low load region where the load is larger than an extremely low load region such as an idle (including an idle state where an auxiliary machine load is applied), the lift / operation angle is large and the center angle is an advanced position. At this time, the intake amount is controlled to a relatively small amount by advancing the intake valve closing timing.

  In the middle load range where the load further increases and the combustion becomes stable, the phase of the central angle is advanced while further increasing the lift / operation angle. The phase of the central angle is the most advanced state at a certain point in the middle load region.

  Further, at the maximum load, the second variable valve mechanism 6 is controlled so that the lift / operation angle is further expanded and the optimum valve timing is obtained. As shown in the figure, the optimum valve lift characteristic varies depending on the engine speed.

  Next, details of the intermediate stopper mechanism that restricts the first variable valve mechanism 5 to a predetermined intermediate operating angle when the engine is stopped and the lift / operating angle control actuator 33 will be described.

  FIG. 4 shows an embodiment of an actuator 33 having an intermediate stopper mechanism 60. As shown in the figure, the actuator 33 is slidably accommodated in a cylindrical cylinder 51 and the cylinder 51. A piston 54 that defines the first hydraulic chamber 52 and the second hydraulic chamber 53, a rod 55 connected to the piston 54, and a link mechanism that transmits the linear movement of the rod 55 as a rotational motion of the control shaft 32. 56. The first hydraulic port 57 that communicates with the first hydraulic chamber 52 and the second hydraulic port 58 that communicates with the second hydraulic chamber 53 are connected to the hydraulic control valve 35, respectively, and an unillustrated hydraulic source (for example, engine oil) By appropriately supplying hydraulic pressure from the pump), the positions of the piston 54 and the rod 55 are determined. When the rod 55 is retracted to the left in the figure, a small lift / operating angle is obtained, and when the rod 55 is projected to the right in the figure, a large lift / operating angle is obtained.

  A stopper pin 61 serving as an intermediate stopper mechanism 60 is provided at the end 51 a on the small operating angle side of the cylinder 51. As shown in detail in FIG. 5, the stopper pin 61 includes a small-diameter pin portion 61 a that can project into the second hydraulic chamber 53 and a large-diameter piston portion 61 b provided at the base end thereof. The piston portion 61b is slidably fitted into a cylinder portion 62 formed in the wall portion of the cylinder 51 in parallel with the axial direction of the cylinder 51, and the inside of the cylinder portion 62 is divided into a hydraulic chamber 63 and a spring storage chamber 64. Partitioning. The stopper pin 61 is always urged in the protruding direction by a coil spring 65 disposed in the spring housing chamber 64, and a predetermined pressure is passed through the oil passage 66 to the hydraulic chamber 63 facing the stopper pin 61. By supplying the hydraulic pressure, the stopper pin 61 is retracted to a position where it does not protrude into the second hydraulic chamber 53.

  In the embodiment of FIG. 4, the oil passage 66 is connected to a hydraulic source (not shown) such as an engine oil pump, either directly or via a solenoid valve (not shown).

  In the second hydraulic chamber 53 of the actuator 33, a disc-like stopper plate 67 that is movable in the axial direction of the actuator 33 is accommodated in the same manner as the piston 54. When the stopper pin 61 protrudes, The front end of the stopper pin 61 is brought into contact with the back surface of the stopper plate 67 so that the stopper plate 67 is pushed out toward the piston 54. The stopper plate 67 allows oil to flow through holes, notches, etc. (not shown), and does not impair the oil flow in and out via the first hydraulic port 58.

  In the configuration as described above, when the hydraulic pressure introduced into the intermediate stopper mechanism 60 via the oil passage 66 decreases as the engine stops, the stopper pin 61 protrudes by the urging force of the coil spring 65, and FIG. As shown, a predetermined amount of the stopper plate 67 is protruded. Therefore, even if the actuator 33 which has been actively controlled is moved to the small operating angle side (left side in the figure) by the reaction force of the valve lift, it is regulated by the stopper plate 67 and held at the intermediate position shown in FIG. The Therefore, when the engine is restarted next time, the lift / operating angle is not a minimum lift / operating angle, but a lift / operating angle of a certain size from the beginning, and can be quickly started by cranking. When the hydraulic pressure introduced into the oil passage 66 increases with the start, the stopper pin 61 moves backward as shown in FIG. 7, and the actuator 33 can be moved to the minimum lift / operating angle without any trouble. In addition, when a solenoid valve is interposed in the hydraulic pressure supply path of the oil path 66, it is possible to positively switch the stopper pin 61 forward and backward.

  Further, as shown in FIG. 6, the oil passage 66 of the intermediate stopper mechanism 60 may be communicated with a first hydraulic port 57 that reaches the first hydraulic chamber 52. According to the configuration of this embodiment, when hydraulic pressure is supplied to the first hydraulic chamber 52 in order to reduce the lift / operating angle, the stopper pin 61 is retracted accordingly. Further, when the hydraulic pressure supplied to the first hydraulic chamber 52 and the oil passage 66 decreases as the engine stops, the stopper pin 61 protrudes and holds the actuator 33 at the intermediate operating angle position.

  Thus, according to the configuration using the stopper pin 61 that advances and retracts hydraulically along the axial direction of the actuator 33, although it cannot be fixed and held at a very large lift / operating angle, it has a very simple configuration and the engine is stopped. The lift / operating angle can be prevented from becoming the minimum lift / operating angle, and the startability of the engine is improved. Further, during normal operation, the control range can be set up to a lift / operating angle smaller than the characteristics at the time of starting, and for example, fuel efficiency can be improved.

  In the embodiment shown in FIGS. 8 and 9, in addition to the intermediate stopper mechanism 60 described above, a similar second intermediate stopper mechanism 60A and second stopper plate 67A are provided at the end of the cylinder 51 on the large operating angle side. Is. The specific configurations of the second intermediate stopper mechanism 60A and the second stopper plate 67A are not particularly different from those of the intermediate stopper mechanism 60 and the stopper plate 67 described above, and thus detailed description thereof is omitted. Note that the oil passage 66A of the second intermediate stopper mechanism 60A may be directly connected to a hydraulic source (not shown) such as an oil pump of an engine, as in the above-described embodiment, or an electromagnetic (not shown). It may be connected via a valve, or may be communicated with a second hydraulic port 58 that reaches the second hydraulic chamber 53.

  The second intermediate stopper mechanism 60A retracts as shown in FIG. 9 when the hydraulic pressure is supplied, and allows the piston 54 to move to the maximum lift / operating angle, and protrudes as shown in FIG. Extrude plate 67A. As a result, for example, it is possible to prevent the piston 54 from sticking at the maximum lift / operating angle position, or to avoid an excessive lift / operating angle due to poor control.

  Next, FIG. 10 shows an actuator 33 in which an intermediate stopper mechanism 60 including a stopper pin 61 that advances and retreats along a direction orthogonal to the moving direction of the piston 54 (that is, the axial direction of the actuator 33) is provided on the side wall of the cylinder 51. 1 shows an embodiment. Since the structure of the intermediate stopper mechanism 60 itself is the same as that of the above-described embodiment described with reference to FIG. 5, the redundant description thereof will be omitted. When the hydraulic pressure introduced via the pressure decreases, the stopper pin 61 protrudes toward the inner peripheral side of the cylinder 51 as shown in the figure, thereby preventing the piston 54 from moving toward the small operating angle side. Accordingly, as in the above-described embodiments, an intermediate lift / operation angle can be obtained at the initial stage of starting.

  Here, as shown in detail in FIG. 11, a stepped recess 71 that receives the tip of the stopper pin 61 is formed on the outer peripheral surface of the piston 54 (particularly, near the first hydraulic chamber 52). The depth from the outer peripheral surface of the recess 71 is shallowest at a position adjacent to the first hydraulic chamber 52 and gradually becomes deeper as the second hydraulic chamber 53 is approached. When the piston 54 is at the left end of the cylinder 51, that is, at the position of the minimum lift / operating angle, the position of the stopper pin 61 is set so that the stopper pin 61 faces the first shallowest step of the recess 71. ing.

  This is because when the stopper pin 61 protrudes when the engine is stopped, the piston 54 may have already moved to the left side (small operating angle side) of the stopper pin 61 in the figure. A so-called ratchet mechanism is constituted by the stopper pin 61 biased in the protruding direction by the coil spring 65 and the stepped recess 71, and the piston 54 is gradually moved by the alternating torque generated by the reaction force of the valve lift. Move to the right side (large operating angle side). That is, when the piston 54 is positioned at the left end of the cylinder 51, the tip of the stopper pin 61 that protrudes due to a decrease in hydraulic pressure comes into contact with the first stage of the recess 71, but the piston 54 is input from the control shaft 32 side. Since the minute vibration is repeated by the alternating torque, the stopper pin 61 engages with the second stage at the moment when the piston 54 moves slightly to the right. This engagement prevents the piston 54 from returning to the left side of the drawing, so that the stopper pin 61 further moves to the third stage and engages at the moment when the piston 54 slightly moves to the right side. By repeating such an operation, the piston 54 moves away from the left end of the cylinder 51 and is held at the intermediate operating angle position until the rotation when the engine stops completely stops or at the initial stage of cranking.

  In the embodiment of FIG. 10, a maximum lift / operation angle stopper 73 and a minimum lift / operation angle stopper 74 are fixedly provided on the inner peripheral surface of the cylinder 51.

  As described above, in the configuration using the intermediate stopper mechanism 60 including the stopper pin 61 that advances and retreats in the direction orthogonal to the moving direction of the piston 54, the spring force for projecting the stopper pin 61 and the hydraulic biasing force for retreating the stopper pin 61 are provided. The piston 54 can be held at a position that is small and relatively far from the minimum lift / operation angle stopper 74. Further, by providing the ratchet mechanism as described above, even if the piston 54 moves to the minimum lift / operating angle stopper 74 side before the stopper 74 protrudes, the lift of an appropriate size is surely ensured at the start.・ A working angle can be secured.

  Next, FIG. 12 shows an embodiment in which a pair of intermediate stopper mechanisms 60, that is, stopper pins 61 are provided on the side wall of the cylinder 51. Also in this embodiment, the intermediate stopper mechanism 60 itself is the same as that described above. The distance between the pair of stopper pins 61 is substantially equal to the axial thickness of the piston 54, and the position of the piston 54 can be regulated in both directions on both sides of the piston 54 as shown. In this configuration, the forward / backward movement of each intermediate stopper mechanism 60, that is, the hydraulic pressure supply is controlled via an electromagnetic valve, and when the control shaft sensor 34 detects that the piston 54 is at a predetermined intermediate operating angle position. It is desirable that each stopper pin 61 is configured to protrude. By providing the intermediate stopper mechanisms 60 on both sides in this manner, the lift / operating angle is reliably maintained in a predetermined state, and starting is more reliable.

  A larger number of intermediate stopper mechanisms 60 may be provided. As an example, the embodiment shown in FIG. 13 includes three intermediate stopper mechanisms 60, which allow the piston 54 to be held at two different intermediate positions.

  Note that the intermediate stopper mechanism 60 of the present invention is not limited to the fixed holding at the intermediate operating angle when the engine is stopped, but also the lift / operating angle in the event of a malfunction of the control when actively switching by the solenoid valve. It can also be used when limiting to an appropriate range.

  In the above embodiment, an example was described in which the present invention is applied to a variable valve apparatus in which the valve lift increases or decreases with the operating angle. However, the present invention is not limited to this, for example, Japanese Patent Laid-Open No. 9-184406. The present invention can be applied to a variable valve device of a type that changes only an operating angle disclosed in Japanese Patent Laid-Open No. 9-268906 and other various types of variable valve devices.

The system block diagram of the intake air amount control apparatus of the internal combustion engine using the variable valve apparatus which concerns on this invention. The perspective view which shows the outline of a 1st variable valve mechanism. The characteristic view which shows the valve lift characteristic in a typical driving | running condition. Sectional drawing which shows one Example of the actuator provided with the intermediate | middle stopper mechanism in the edge part. Sectional drawing which shows only an intermediate | middle stopper mechanism. Sectional drawing which shows the Example which connected the oil path of the intermediate | middle stopper mechanism to the hydraulic port. Sectional drawing which shows the state of the intermediate | middle stopper mechanism in normal driving | operation. Sectional drawing of the Example which added the 2nd intermediate | middle stopper mechanism to the large operating angle side. Sectional drawing which shows the state in the normal driving | operation. Sectional drawing which shows the Example provided with the intermediate | middle stopper mechanism in the cylinder side wall. Explanatory drawing which shows the detail of the recessed part of a piston outer peripheral surface. Sectional drawing which shows the Example provided with a pair of intermediate | middle stopper mechanism in the cylinder side wall. Sectional drawing which shows the Example provided with the three intermediate | middle stopper mechanisms in the cylinder side wall.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 ... Intake valve 5 ... 1st variable valve mechanism 6 ... 2nd variable valve mechanism 10 ... Control unit 32 ... Control shaft 51 ... Cylinder 54 ... Piston 60 ... Intermediate stopper mechanism 61 ... Stopper pin 63 ... Hydraulic chamber 65 ... Coil Spring 71 ... recess

Claims (8)

It has a control shaft whose rotational position is controlled by a linearly moving hydraulic actuator, the valve operating angle is continuously changed according to the rotational position of this control shaft, and the hydraulic actuator is controlled by the reaction force accompanying the valve lift. In a variable valve operating apparatus for an internal combustion engine that receives an urging force in the direction of reducing the operating angle
An internal combustion engine characterized in that the hydraulic actuator is provided with an intermediate stopper mechanism that projects into the cylinder of the hydraulic actuator when the engine is stopped, and the movement of the piston of the hydraulic actuator in the direction of reducing the operating angle is restricted at an intermediate position. Variable valve device.   2. The variable valve operating apparatus for an internal combustion engine according to claim 1, wherein the intermediate stopper mechanism includes a stopper pin that advances and retreats along a moving direction of the piston at an end portion on a small operating angle side of the hydraulic actuator. .   The intermediate stopper mechanism includes a spring for urging the stopper pin in a protruding direction toward the piston, and a hydraulic chamber for retracting the stopper pin against the urging force of the spring, and the hydraulic chamber The variable valve operating apparatus for an internal combustion engine according to claim 2, wherein the stopper pin is advanced and retracted by a hydraulic pressure supplied to the internal combustion engine.   The hydraulic actuator includes a stopper plate that can move in the direction of movement of the piston, and the stopper plate moves as the stopper pin advances and retreats. A variable valve operating apparatus for an internal combustion engine according to claim 1.   2. The variable motion of the internal combustion engine according to claim 1, wherein the intermediate stopper mechanism includes a stopper pin that is provided on a side wall of the hydraulic actuator and moves forward and backward along a direction orthogonal to a moving direction of the piston. Valve device.   The intermediate stopper mechanism includes a spring that biases the stopper pin in a protruding direction so as to engage with the piston, and a hydraulic chamber for retracting the stopper pin against the biasing force of the spring. 6. The variable valve operating apparatus for an internal combustion engine according to claim 5, wherein the stopper pin is advanced and retracted by a hydraulic pressure supplied to the hydraulic chamber.   7. The variable valve operating apparatus for an internal combustion engine according to claim 6, wherein a stepped recess that forms a ratchet mechanism together with the stopper pin is formed on an outer peripheral surface of the piston that receives the tip of the stopper pin.   6. The variable valve operating apparatus for an internal combustion engine according to claim 5, wherein a plurality of the stopper pins are provided so as to restrict the movement of the piston in both directions.

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