JP2011236779A - Variable valve system for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To adjust displacement without the need of detaching members in the case that displacement is generated in a valve stopping/returning changeover mechanism.SOLUTION: The variable valve system links or detaches first and second locker arms of each cylinder by a changeover pin. In the case that a link arm is in a first position not driven by an actuator, the changeover pin has the first and second locker arms in a linked state. In the case that the link arm is in a second position displaced by the actuator, it is in a displaced position in a pin hole according to the displacement of the link arms so as to have the first and second locker arms in a non-linked state. The variable valve mechanism has a position adjusting means for adjusting the position of a locker shaft. The relative positional relationship of the first and second locker arms and the changeover pin is adjusted by moving the position of the link arm according to the position adjustment of the first locker shaft for adjusting the contact position of the link arm and the changeover pin.

Description

  The present invention relates to a variable valve operating apparatus for an internal combustion engine.

  For example, Patent Document 1 discloses a variable valve mechanism that switches the lift of intake valves or exhaust valves of all cylinders using a pneumatic actuator. This variable valve mechanism includes two types of cams, a low speed small cam and a high speed large cam for each cylinder, a low speed rocker arm that contacts the small cam, and a high speed rocker arm that contacts the large cam. It has two types of rocker arms. Lock pins that can be pushed by a control plate are attached to the low-speed rocker arm and the high-speed rocker arm.

  When the lock pin is not pushed in this variable valve mechanism, the high speed rocker arm and the low speed rocker arm are separated, and the intake valve (or exhaust valve) is moved by the small cam through the low speed rocker arm. Lifted. On the other hand, when the lock pin is pushed, the lock pin is engaged with the high speed rocker arm, and the low speed rocker arm and the high speed rocker arm are connected to each other. At this time, the intake valve (or exhaust valve) is lifted by the large cam via the connected rocker arm.

  In the variable valve mechanism of Patent Document 1, connection / separation of the high-speed and low-speed rocker arms is performed by pushing a lock pin, and the lock pin is pushed by a control plate attached to a control rod. Done. When the gas pressure actuator is actuated, the control rod moves in the specified axial direction due to negative pressure. When the control rod moves, the lock pin is pushed and the rocker arm for high speed and low speed is connected. To do. On the other hand, when the negative pressure of the gas pressure actuator is released, the control rod and control plate are pushed back into place, so the lock pin is disengaged and the rocker arm for high speed and low speed is separated. It will be in the state. With this switching mechanism, the lift amount of the intake valve (or exhaust valve) is switched.

JP 2002-242628 A JP 07-119424 A

  In the case of a mechanism for connecting / separating two rocker arms using a switching pin, such as the lock pin of the invention of the above-mentioned Patent Document 1, the cylinders are stopped in each cylinder by the displacement of the relative position between the switching pin and the rocker arm. Abnormal valve operation such as valve return abnormality may occur. The occurrence of valve stop / return abnormality can cause drivability to deteriorate, which is not preferable. For this reason, it is necessary to correct the position of the switching pin or the rocker arm. Conventionally, in order to correct the displacement of the switching pin or the rocker arm, it is necessary to remove all the switching pins or the rocker arm. The work was complicated and difficult.

  The present invention has been made to solve the above-described problems. When a displacement occurs between members of a switching mechanism that switches between valve stop and return, the displacement is adjusted without removing the entire member. It is an object of the present invention to provide a variable valve operating apparatus for an internal combustion engine which is improved so as to be able to achieve this.

A first invention is a variable valve operating apparatus for an internal combustion engine,
Each of the at least two cylinders includes a first rocker arm that is disposed between the cam and the valve and swings in synchronization with the cam, and a second rocker arm that can push the valve, and the operation of the cam A transmission member for transmitting force to the valve;
A rocker shaft that is shared by the at least two cylinders and that swingably supports the first rocker arm and the second rocker arm;
A link shaft disposed so as to be axially displaceable inside the rocker shaft;
Link arms arranged corresponding to each of the cylinders, each connected to the link shaft, and displaced integrally with the link shaft;
An actuator that is shared by the at least two cylinders and that displaces the link arm and the link shaft by driving;
In each cylinder, the cylinder is movably disposed in a pin hole formed in each of the first rocker arm and the second rocker arm, and at one end thereof, a return spring installed in the second rocker shaft is abutted. Arranged so as to contact the link arm at the other end,
A state in which the first rocker arm and the second rocker arm are connected to each other at a position biased by the return spring when the link arm is in the first position not receiving the driving force of the actuator. age,
When the link arm is in the second position displaced by the actuator, the first rocker arm and the second rocker arm are in a position displaced in the pin hole by the displacement of the link arm. A switching pin that is in a disconnected state; and
Position adjusting means for adjusting a contact position of the link arm and the switching pin in the axial direction, and adjusting a relative positional relationship between the first rocker arm and the second rocker arm, and the switching pin;
It is characterized by providing.

  In a second aspect based on the first aspect, the position adjusting means moves the link shaft and the link arm together by moving the position of the rocker shaft, thereby moving the link arm and the switching arm. The contact position with the pin is adjusted.

  According to a third invention, in the first or second invention, the position adjusting means is an adjusting screw installed on a support member that supports the rocker shaft.

  According to the first aspect, the relative positional relationship between the first rocker arm and the second rocker arm and the switching pin can be adjusted by the position adjusting means. Accordingly, the relative positional relationship between the first and second rocker arms and the switching pin can be adjusted without removing the first and second rocker arms and the switching pin itself, and the work for position adjustment is facilitated. can do.

  According to the second invention, the position of the link shaft and the link arm can be moved simultaneously by adjusting the position of the rocker shaft. Thereby, the position of the switching pin urged to the link arm side can be moved to the moving position of the link arm. Therefore, the relative positional relationship between the first rocker arm and the second rocker arm and the switching pin can be easily adjusted without removing the first and second rocker arms and the switching pin itself. Work can be facilitated.

  According to the third invention, the position adjusting means for adjusting the position of the rocker shaft is an adjusting screw installed on the support member of the rocker shaft. Accordingly, the rocker shaft can be moved by simply rotating the screw without removing each member, and as a result, the relative positional relationship between the first and second rocker arms and the switching pin can be adjusted. .

1 is a diagram schematically showing an overall configuration of a variable valve operating apparatus for an internal combustion engine according to an embodiment of the present invention.

Embodiment.
Hereinafter, an embodiment of the present invention will be described with reference to FIG.
[Configuration of variable valve gear]
FIG. 1 is a diagram schematically showing an overall configuration of a variable valve operating apparatus 10 for an internal combustion engine according to an embodiment of the present invention. FIG. 1 is a plane including an axis of a rocker shaft 22 and an axis of switching pins 36, 38, and 44, which will be described later. FIG. The internal combustion engine of the present embodiment is an in-line four-cylinder engine having four cylinders (# 1 to # 4). Each cylinder of the internal combustion engine is provided with two intake valves and two exhaust valves, and the variable valve apparatus 10 includes two intake valves or two exhaust valves disposed in each cylinder. It functions as a driving mechanism.

  The variable valve operating apparatus 10 includes a camshaft 12. The camshaft 12 is provided with one main cam 14 and one sub cam 16 per cylinder. Each cylinder of the internal combustion engine is provided with a first rocker arm 18 and a second rocker arm 20 adjacent to each other, and is rotatably supported by a single rocker shaft 22. The camshaft 12 and the rocker shaft 22 are supported by a cylinder head 24 (or cam carrier).

  A pair of adjustment screws 26 for adjusting the position of the rocker shaft 22 are provided at both ends of the rocker shaft 22. The adjusting screw 26 is installed on the rocker shaft 22 support portion of the cylinder head 24 (support member). The relative position of the rocker shaft 22 in the axial direction with respect to the cylinder head 24 can be adjusted by the rotation of the adjusting screw 26.

  A cam roller 28 is rotatably attached to the first rocker arm 18. The first rocker arm 18 is biased by a coil spring (not shown) attached to the rocker shaft 22 so that the cam roller 28 is always in contact with the main cam 14. On the other hand, the second rocker arm 20 is an arm that drives two valves, and is configured to surround the first rocker arm 18.

  A first pin hole 32a concentric with the cam roller 28 is formed in the support shaft 30 of the cam roller 28. Two holes are formed in the second rocker arm 20 at positions corresponding to the first pin holes 32a. Second pin holes 32L and 32R are formed. The centers of these pin holes 32a, 32L, 32R are arranged in the same arc shape with the rocker shaft 22 being the rotation center of the rocker arms 18, 20 as the center. Further, when the cam roller 28 is in contact with the base circle of the main cam 14 and the second rocker arm 20 is in contact with the base circle of the sub cam 16, the position of the first pin hole 32a and the second pin hole The positions 32L and 32R coincide with each other.

  A cylindrical switching pin 36 is movably inserted into the first pin hole 32a. A cylindrical switching pin 38 that contacts the switching pin 36 is movably inserted into the second pin hole 32L (left side in FIG. 1). The end of the second pin hole 32L into which the switching pin 38 is inserted is closed by the cap 40 on the side opposite to the first rocker arm 18 side, and the switching pin 38 is placed inside the second pin hole 32L. A return spring 42 that biases toward the direction of the rocker arm 18 (hereinafter referred to as “advance direction”) is disposed. A cylindrical switching pin 44 that is in contact with the switching pin 36 is movably inserted into the second pin hole 32R (right side in FIG. 1).

  In the # 4 cylinder, a first link arm 46 that contacts the switching pin 44 is disposed on the side of the second rocker arm 20 (right side in FIG. 1). A protrusion 46 a is provided at the tip of the first link arm 46. On the other hand, in the # 1 to # 3 cylinders, a second link arm 48 that contacts the switching pin 44 is disposed on the side of the second rocker arm 20 (right side in FIG. 1).

  The first link arm 46 and the second link arm 48 are fixed to the link shaft 50. The link shaft 50 is inserted into the rocker shaft 22 formed in a hollow shape. The link shaft 50, the first link arm 46, and the second link arm 48 are configured to be displaceable in the axial direction within the restricted range in the rocker shaft 22 without being hindered from moving. Yes.

  The link shaft 50 is divided into a first link shaft 50a on the # 3 and # 4 cylinder side and a second link shaft 50b on the # 1 and # 2 cylinder side. The first link shaft 50 a and the second link shaft 50 b are connected via a delay mechanism 52.

  The delay mechanism 52 includes an intra-delay mechanism link shaft 54 having an abutting portion 54a that abuts the second link shaft 50b at one end. The contact portion 54a is formed with a larger diameter than other portions. The other end side of the in-delay mechanism link shaft 54 is inserted into a hollow first link shaft 50a. A delay mechanism spring 56 having a predetermined spring length is disposed between the contact portion 54a and the end portion of the first link shaft 50a on the delay mechanism 52 side. The in-delay mechanism link shaft 54 is movable in the axial direction within the link shaft within a predetermined range.

  In the camshaft 12, a columnar portion 12 a formed in a columnar shape is formed at a portion facing the protruding portion 46 a provided on the first link arm 46. A spiral guide rail 62 extending in the circumferential direction is formed on the outer peripheral surface of the cylindrical portion 12a. Here, the guide rail 62 is formed as a spiral groove.

  This variable valve operating apparatus 10 includes an electromagnetic solenoid 64 as an actuator that generates a driving force for engaging (inserting) the protrusion 46 a with the guide rail 62. The electromagnetic solenoid 64 is disposed at a position where the drive shaft 64 a can press the pressing surface 46 c of the first link arm 46 toward the guide rail 62. Further, the pressing surface 46c that contacts the drive shaft 64a of the first link arm 46 is provided with a cutout portion that engages with the drive shaft 64a in a state described later.

  The ECU (Electronic Control Unit) 66 is an electronic control unit for controlling the operating state of the internal combustion engine. The ECU 66 is electrically connected to the electromagnetic solenoid 64, for example, and controls the duty of the electromagnetic solenoid 64 by issuing a control signal.

[Operation of variable valve mechanism]
(When the valve is operating)
When the valve is operated, the drive of the electromagnetic solenoid 64 is turned off. In this state, the first link arm 46 is separated from the camshaft 12, and is positioned at the displacement end Pmax1 (first position) under the urging force of the return spring 42. The link shaft 50 and the second link arm 48 connected to the link shaft 50 are displaced in conjunction with the first link arm 46 and are located on the advancing direction side (right side in FIG. 1).

  In this state, since the force against the urging force of each return spring 42 is not acting, the switching pin 36 is inserted into both the pin holes 32a and 32R, and the switching pin 38 is inserted into both the pin holes 32a and 32L. It has become a state. As a result, the first rocker arm 18 and the second rocker arm are connected by the switching pins 36 and 38. In such a connected state, the first rocker arm 18 and the second rocker arm 20 are swung by the acting force of the main cam 14 received by the first rocker arm 18. Therefore, a normal valve lift operation is performed according to the profile of the main cam 14.

(When valve is stopped)
When the valve is stopped, energization of the electromagnetic solenoid 64 is turned on at the timing when the common base circle section of the main cam 14 for the # 3 and # 4 cylinders arrives. As a result, the first link arm 46 rotates about the rocker shaft 22, and the protrusion 46 a engages with the guide rail 62. As a result, the protrusion 46a is guided by the guide rail 62, and the first link arm 46 moves toward the displacement end Pmax2 (second position) using the rotational force of the camshaft 12. Further, in conjunction with the movement of the first link arm 46, the second link arm 48 of the # 3 cylinder connected to the first link shaft 50a and the first link shaft 50a moves.

  When the first link arm 46 reaches the displacement end Pmax2 in this way, the force against the return spring 42 is exerted by the displacement of the first link arm 46 and the second link arm 48 of the # 3 cylinder. 38 are returned into the pin holes 32a and 32L, respectively. As a result, the gaps between the first rocker arm 18 and the second rocker arm 20 of the # 3 and # 4 cylinders coincide with the positions of the contact surfaces of the switching pins 36, 38, 44, and the first and second rocker arms 18, 20 are aligned. Is disconnected. As a result, the acting force of the main cam 14 is transmitted only to the first rocker arm 18 and is not transmitted to the second rocker arm 20. At this time, the secondary cam 16 comes into contact with the second rocker arm 20, but here the secondary cam 16 is a zero lift cam, so the second rocker arm 20 is stationary and the valve lift operation is closed. Stops at the valve position.

  Even if energization to the electromagnetic solenoid 64 is turned on, the second link shaft 50b is not displaced immediately, and the delay mechanism spring 56 is first contracted. In the state where the delay mechanism spring 56 is contracted, when the swing operation (valve lift operation) of the first rocker arm 18 of the # 1 cylinder is finished, the common base circle section of the main cam 14 for the # 1 and # 2 cylinders arrives. To do. At this timing, the delay mechanism spring 56 is extended and the second link shaft 50b is displaced in response to the displacement of the first link shaft 50a. When the second link arm 48 is displaced by the displacement of the second link shaft 50b, the switching pins 36 and 38 are pushed back in the same manner as in the case of the # 3 and # 4 cylinders, and the first and second rocker arms 18 and 20 are moved. Unconnected state. As a result, the lift operation of the valve is also stopped at the closed position in the # 1 and # 2 cylinders.

  Incidentally, the bottom of the guide rail 62 becomes shallower toward the displacement end Pmax2 side, and finally reaches the surface of the cylindrical portion 12a. The protrusion 46a is guided by the guide rail 62 and moves to the Pmax2 side. When the first link arm 46 reaches the displacement end Pmax2, the protrusion 46a is taken out to the surface of the cylindrical portion 12a. In this state, the drive shaft 64a is engaged with a notch formed in the pressing surface 46c of the first link arm 46, and the first link arm 46 is restricted from moving toward the displacement end Pmax1. The

[Batch position adjustment with adjusting screw]
As described above, in the present embodiment, the first and second rocker arms 18 and 20 are disconnected from each other by returning the switching pins 36 and 38 into the pin holes 32a and 32L, respectively. , 38 are inserted into the pin holes 32R and 32a, respectively, so that they are connected. That is, the contact surface position of the switching pins 36 and 38, the contact surface position of the switching pins 36 and 44, and the gap between the first rocker arm 18 and the second rocker arm 20 are in the same position. The first rocker arm 18 and the second rocker arm 20 are not connected.

  Therefore, if the positional relationship between the two contact surface positions between the switching pins 36, 38, and 44 and the gap between the first and second rocker arms 18 and 20 is deviated, switching between valve stop and return is not correctly executed. It will be. For this reason, in this embodiment, when the positional relationship between the switching pins 36, 38, 44 and the first and second rocker arms 18, 20 is shifted, the adjustment screw 26 is used to correct the shift. Is installed. As described above, the adjusting screw 26 is installed on the support portion of the rocker shaft 22 outside the cylinder head 24 and can move the position of the rocker shaft 22 relative to the cylinder head 24 in the axial direction.

  For example, when the rocker shaft 22 is moved in the advance direction by the adjusting screw 26, the link shaft 50 installed therein and the first and second link arms 46, 48 connected to the link shaft 50 are also moved simultaneously. When the first and second link arms 46, 48 move in the advance direction, the switching pins 36, 38, 44 of all cylinders move in the advance direction by the urging force of the return spring 42 by the amount of movement.

  On the other hand, when the rocker shaft 22 is moved in the direction opposite to the advancing direction by the adjusting screw 26, the first and second link arms 46, 48 are moved in conjunction with this movement, and the movement amount is changed by the switching pins 38, 36. 44 are pushed back against the urging force of the return spring 42.

  By adjusting the position of the rocker shaft 22 as described above, the positions of the switching pins 36, 38, 44 of all the cylinders can be moved collectively. At this time, the first and second rocker arms 18 and 20 are fixed at fixed positions. Therefore, the relative position between the contact surface position between the switching pins 36, 38, and 44 and the gap between the first and second rocker arms 18 and 20 can be corrected collectively for all cylinders.

  The relative position is corrected by the adjusting screw 26 while the cylinder head 24 is opened and the positions of the switching pins 36, 38, 44 and the positions of the first and second rocker arms 18, 20 are confirmed.

  As described above, the adjustment screw 26 collectively corrects the deviation between the clearance between the first and second rocker arms 18 and 20 of each cylinder and the contact surface position between the switching pins 36, 38 and 44. be able to. Furthermore, in the apparatus of the present embodiment, the position adjustment can be performed collectively for all cylinders by the following position method. The following method may be performed in combination with the position adjustment by the adjustment screw 26 described above.

[Other batch position adjustment methods]
(Adjustment by protrusion 46a)
During the valve stop holding operation, the protrusion 46 a moves along the guide rail 62. The engagement between the protrusion 46a and the guide rail 62 becomes a force that restricts the movement of the first and second link arms 46 and 48 by being urged by the return spring 42. Therefore, if the diameter of the projection 46a is reduced and the gap between the projection 46a and the guide rail 62 is increased, the return spring 42 is pushed by the gap, and the first link arm 46 and the second link interlocked therewith. The position with the arm 48 is adjusted to the advance direction side. On the other hand, if the diameter of the protrusion 46a is increased and the gap between the protrusion 46a and the guide rail 62 is reduced, the return spring 42 is pushed back more in the direction opposite to the advance direction, and the first and second links. The arms 46 and 48 are adjusted in the direction opposite to the advance direction. As described above, by changing the diameter of the protrusion 46a, the relative positions of the switching pins 36, 38, 44 and the first and second rocker arms 18, 20 can be collectively determined during the valve stop operation. Can be adjusted.

  In order to adjust the relative position collectively during the valve stop operation by this method, the protrusion 46a is appropriately replaced with one having a different outer diameter. For example, when it is desired to adjust the position of the switching pins 36, 38, 44 in the advance direction, the diameter of the protrusion 46a may be reduced, and when it is desired to adjust in the opposite direction, the diameter of the protrusion 46a may be increased. For this reason, in the present embodiment, when performing such adjustment work, a plurality of protrusions 46a having different diameters are prepared in advance.

(Adjustment with drive shaft 64a)
Further, as described above, the drive shaft 64a engages with the cutout portion provided in the first link arm 46 and holds the first link arm 46 in the valve stop holding state. That is, the restriction of the operation of the first link arm 46 due to the engagement between the drive shaft 64a and the notch serves as a force against the urging force of the return spring 42 in all cylinders. Here, if the diameter of the drive shaft 64a is increased, the gap between the notch portion and the drive shaft 64a is reduced, so that a margin for movement in the advancing direction due to the urging force of the return spring 42 is reduced. Therefore, the entire link shaft 50 is adjusted in the direction opposite to the advancing direction. On the other hand, if the drive shaft 64a is made smaller, the gap between the notch and the drive shaft 64a becomes larger, so that the allowance for movement of the first link arm 46 in the advance direction is increased by the biasing force of the return spring. Therefore, the entire link shaft 50 can be moved in the advance direction by the margin. In this way, by changing the diameter of the drive shaft 64a, the relative positions of the switching pins 36, 38, 44 and the first and second rocker arms 18, 20 in the valve stop holding state can be adjusted.

  In order to adjust the relative position collectively when holding the valve stopped, the drive shaft 64a is appropriately replaced with one having a different outer diameter. For example, when it is desired to adjust the position of the switching pins 36, 38, 44 in the advance direction, the diameter of the drive shaft 64a may be reduced, and when it is desired to adjust in the reverse direction, the diameter of the drive shaft 64a may be increased. For this reason, in the present embodiment, when performing this adjustment work, a plurality of drive shafts 64a having different diameters are prepared in advance.

[Individual position adjustment]
With the above-described method, it is possible to adjust the positional deviation for all cylinders at once. In the present embodiment, when it is necessary to adjust the displacement for each cylinder, the position can be adjusted individually or for each of a plurality of cylinders by the following method.

(Adjustment method 1)
Two link shafts 50 a and 50 b are installed in the rocker shaft 22, and a delay mechanism 52 is installed between the link shafts 50 to determine the position thereof. By adding a member such as a shim to the contact portion 54a of the delay mechanism 52, the distance between the link shafts 50a and 50b can be changed, and the position of the one link shaft 50a or 50b can be shifted. As a result, the relative positions of the cylinder switching pins 36, 38, 44 and the first and second rocker arms 18, 20 of the cylinder that the first link shaft 50a or the second link shaft 50b whose position has been adjusted are corrected.

  The first and second link arms 46 and 48 fixed to the link shaft 50 are attached to the rocker shaft 22 by connecting pins. Therefore, when adjusting the position by adding a shim or the like between the link shafts 50a and 50b, the connecting pin is removed, the link shaft 50a or 50b on one side is removed from the rocker shaft 22, and a shim or the like is added. The removed link shaft 50a or 50b is returned and the connect pin is attached. In this adjustment method, a plurality of shims having different thicknesses are prepared in advance.

(Adjustment method 2)
The positions of the first and second rocker arms 18 and 20 are determined by fine adjustment by an E ring (not shown) attached to the rocker shaft 22. By changing the thickness of the E-ring, the positions of the first and second rocker arms 18 and 20 are shifted, whereby the switching pins 36, 38, and 44 are relative to the first and second rocker arms 18 and 20. Individual positional relationship.

  Here, an operation of replacing the E-ring installed on the rocker shaft 22 is performed. When performing this operation, prepare a plurality of E-rings having different thicknesses, and contact the contact surface between the switching pins 36, 38, 44 and the first and second rocker arms 18, 20 when the valve is stopped. The E-ring having an appropriate thickness is selected and replaced so that the gap between the two matches.

  As described above, in the present embodiment, the adjustment screw 26 for adjusting the position of the rocker shaft 22 is provided, so that the first and second rocker arms 18 and 20 generated in all the cylinders, the switching pin 36, The shift of the relative position with respect to 38 and 44 can be adjusted collectively. In addition, even when the adjustment screw 26 cannot be adjusted only by adjusting the rocker shaft 22, the position adjustment can be performed more finely by changing the diameters of the protrusion 46 a and the drive shaft 64 a together with the position adjustment.

  In addition, even if there is a variation in the position shift for each cylinder and batch position adjustment cannot cope with the shift of each cylinder, after performing the overall position adjustment in a lump, the individual cylinder is The position adjustment can be performed for each cylinder or for several cylinders.

  By such position adjustment, the first and second rocker arms 18 and 20 and the switching pins 36, 38, and 44 can be easily removed from the outside of the cylinder head 24 or with the cylinder head 24 opened. The positional relationship can be corrected.

  In the present embodiment, the case where the adjusting screw 26 is installed as the mechanism for adjusting the rocker shaft 22 has been described. However, the present invention is not limited to this, and any other means may be used as long as the mechanism can adjust the position of the rocker shaft 22.

  In the present embodiment, a case has been described in which a zero lift cam is used as the auxiliary cam 16 to switch between valve return and valve stop. However, the present invention is not limited to this, and the present invention can be similarly applied to a mechanism that changes the lift amount of the valve using two cams having different diameters.

  In the above embodiment, when referring to the number of each element, quantity, quantity, range, etc., the reference is made unless otherwise specified or the number is clearly specified in principle. The invention is not limited to the numbers. Further, the structure and the like described in the present embodiment are not necessarily essential to the present invention unless otherwise specified or clearly specified in principle.

DESCRIPTION OF SYMBOLS 10 Variable valve apparatus 12 Cam shaft 12a Cylindrical part 18 1st rocker arm 20 2nd rocker arm 22 Rocker shaft 24 Cylinder head 26 Adjustment screw 32a, 32L, 32R Pin hole 36, 38, 44 Switching pin 40 Cap 42 Return spring 46 First link arm 46a Protruding portion 46c Pressing surface 48 Second link arm 50, 50a, 50b Link shaft 52 Delay mechanism 62 Guide rail 64 Electromagnetic solenoid 64a Drive shaft

Claims (3)

Each of the at least two cylinders includes a first rocker arm that is disposed between the cam and the valve and swings in synchronization with the cam, and a second rocker arm that can push the valve, and the operation of the cam A transmission member for transmitting force to the valve;
A rocker shaft that is shared by the at least two cylinders and that swingably supports the first rocker arm and the second rocker arm;
A link shaft disposed so as to be axially displaceable inside the rocker shaft;
Link arms arranged corresponding to each of the cylinders, each connected to the link shaft, and displaced integrally with the link shaft;
An actuator that is shared by the at least two cylinders and that displaces the link arm and the link shaft by driving;
In each cylinder, the cylinder is movably disposed in a pin hole formed in each of the first rocker arm and the second rocker arm, and at one end thereof, a return spring installed in the second rocker shaft is abutted. Arranged so as to contact the link arm at the other end,
A state in which the first rocker arm and the second rocker arm are connected to each other at a position biased by the return spring when the link arm is in the first position not receiving the driving force of the actuator. age,
When the link arm is in the second position displaced by the actuator, the first rocker arm and the second rocker arm are in a position displaced in the pin hole by the displacement of the link arm. A switching pin that is in a disconnected state; and
Position adjusting means for adjusting a contact position of the link arm and the switching pin in the axial direction, and adjusting a relative positional relationship between the first rocker arm and the second rocker arm, and the switching pin;
A variable valve operating apparatus for an internal combustion engine, comprising: The position adjusting means includes
The contact position between the link arm and the switching pin is adjusted by moving the link shaft and the link arm together by moving the position of the rocker shaft. The variable valve operating apparatus for an internal combustion engine.   3. The variable valve operating apparatus for an internal combustion engine according to claim 1, wherein the position adjusting means is an adjusting screw installed on a support member that supports the rocker shaft.

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