JP2009281164A - Variable valve gear of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable valve gear capable of miniaturizing the device itself and increasing a lift variation of an air intake valve. <P>SOLUTION: This variable valve gear is provided with a camshaft 4 on an outer periphery of which an egg-shaped driving cam 5 is integrally provided, a control shaft 22 on an outer periphery of which control cam 23 is provided, a locker arm 15 a recessed part 18 formed on one end 15a of which fits on the control cam and oscillates as an oscillating fulcrum and an oscillating cam 7 to actuate the air intake valve 3 to open and close by moving to oscillate by an oscillating force transmitted through a link rod 16 from the locker arm. The locker arm is devised so as to be linked to the oscillating cam through the link rod on the other end part 15b to actuate the air intake valve to open and close through the link rod and the oscillating cam as the driving cam rolls and makes contact with a roller 20 provided roughly in the center and to vary a lift quantity of the air intake valve by the oscillating cam by eccentrically rotating the control cam. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a variable valve operating apparatus for an internal combustion engine that can vary at least a valve lift amount of an intake valve and an exhaust valve, which are engine valves, according to an engine operating state.

  As is well known, the intake / exhaust valve lifts are used to improve fuel efficiency at low engine speeds and low loads, to ensure stable driving performance, and to ensure sufficient output by improving intake charging efficiency at high speeds and high loads. Various variable valve operating apparatuses that variably control the amount and the operating angle have been conventionally provided, and one of them is described in Patent Document 1 below.

  Briefly, a rocker arm whose base end is swingably supported by a support shaft and whose tip is in contact with the engine valve, and one end of the rocker arm is pivotable on the tip of the rocker arm via a pin. A connected first link, a second link whose one end is rotatably connected to the other end of the first link via a shaft, and a second link rotatably connected to the other end of the second link A support shaft arranged in parallel with the pin and the shaft, an annular cam slipper provided at an end of the shaft connecting the first and second links, and a cam slipper on the outer peripheral surface of the cam slipper. It is mainly composed of a drive cam that contacts and opens and closes the engine valve.

  The lift amount of the drive cam is transmitted to the cam slipper, and the movement amount is moved while rotating the first link and the second link about the support shaft. The sum of this movement is transmitted to the rocker arm to open and close the engine valve.

Then, by turning the first support arm arranged on the side of the first and second links about the support arm mounting shaft, the bending angle of both the links is changed by the actuator and the arcuate gear. By doing so, the lift amount of the engine valve is changed.
JP 2004-239249 A (FIGS. 14 and 15)

  However, in the conventional variable valve operating apparatus, the drive cam is in rolling contact with a cam slipper provided on a shaft connecting the first link and the second link. The amount of change in lift of the engine valve cannot be increased unless the amount of movement of the support shaft by the gear is greatly changed.

  The present invention has been devised in view of the technical problem of the conventional variable valve operating device, and the invention according to claim 1 is supported by a support shaft so as to be swingable, and the engine is configured by swinging. A rocking cam that opens and closes the valve, a control cam that is rotatably provided, a rocker arm that is supported by the control cam so as to be rockable, and the other end of the rocker arm and the rocking cam. Then, a link rod that moves at least in the valve opening direction of the engine valve in response to the rocker arm swings, and a part between one end side and the other end side of the rocker arm, and a rotational driving force is generated from the crankshaft. And a drive cam that presses the rocker arm when applied.

  The invention described in claim 6 is, in particular, the center of the support shaft, the center of the link portion between the swing cam and the link rod, the center of the link portion between the link rod and the rocker arm, and the control cam. The feature is that the center of rotation is connected in a substantially U shape.

  The invention described in claim 7 is characterized in that, in particular, a four-bar linkage mechanism is constituted by the rocker arm, the link rod, and the swing cam.

  According to the first aspect of the present invention, at least the valve lift amount of the engine valve can be made variable in accordance with the rotational position of the control cam, and the drive cam is brought into contact with an intermediate position between both end portions of the rocker arm. As a result, the lift amount of the drive cam can be directly transmitted to the engine valve via the rocker arm, the link rod, and the swing cam, so that the lift change amount can be increased while reducing the size of the device. .

Embodiments of a variable valve operating apparatus for an internal combustion engine according to the present invention will be described below in detail with reference to the drawings. In this embodiment, the variable valve device is applied to the intake side of an internal combustion engine.
[First embodiment]
That is, as shown in FIGS. 1 to 6, the variable valve operating apparatus according to this embodiment is provided in the cylinder head 1 so as to be slidable via a valve guide (not shown), and per cylinder for opening and closing the intake port. Two intake valves 3, an intake-side camshaft 4 disposed above the intake valve 3 in the longitudinal direction of the engine, and two drive cams 5 fixed for each cylinder of the camshaft 4. Between a pair of swing cams 7 for opening each intake valve 3 via a swing arm 6 that is a follower disposed at the upper end of each intake valve 3, and between the drive cam 5 and the swing cam 7. A four-bar link type transmission mechanism 8 that links and converts the rotational force of the drive cam 5 into a swinging motion and transmits it as a swinging force (valve opening force) of the swinging cam 7, and a rocker arm to be described later of the transmission mechanism 8. The valve lift amount of each intake valve 3 can be changed by changing the oscillating fulcrum of 15 And a, a control mechanism 9 for variably controlled in accordance with the operating condition.

  The intake valve 3 is configured such that each open end of the intake port is opened by a valve spring 10 that is elastically mounted between a bottom portion of a substantially cylindrical bore housed in the upper end portion of the cylinder head 1 and a spring retainer at the upper end portion of the valve stem. It is biased in the closing direction.

  Both ends of the camshaft 4 are rotatably supported by bearings (not shown) provided at the top of the cylinder head 1 and are wound around a driven sprocket provided at one end or the driven sprocket. Rotational force is transmitted from the crankshaft of the engine via a timing chain or the like, and rotates in the clockwise direction (arrow direction) in FIG.

  The drive cam 5 is formed in a generally oval shape and is arranged for each swing cam 7, and the outer peripheral surface is formed in an eccentric cam profile so as to be integrated with the camshaft 4. It is fixed to.

  Each of the swing arms 6 has a bottom surface of the concave one end 6 a in contact with a stem end of each intake valve 3, and a spherical bottom surface of the other end 6 b in a holding hole 2 formed in the cylinder head 1. The hydraulic lash adjuster 11 is held in contact with and supported by the hydraulic lash lash adjuster 11 so as to swing about the pivot fulcrum. Further, the swing arm 6 is rotatably supported by rollers 12 with which the swing cams 7 abut at a substantially central position in a hollow shape so that the transmission resistance with the swing cam 7 can be reduced by the rollers 12. It has become.

  The hydraulic lash adjuster 11 has a general structure, and is provided with a bottomed cylindrical body 13a inserted and fixed in the holding hole 2, and slidable upward from the body 13a. And a plunger 13b whose spherical tip is in contact with the other end 6b of the swing arm 6 from below, and in the reservoir in a high-pressure chamber defined between the inner bottom of the body 13a and the partition wall of the plunger 13b. Is appropriately supplied via a check valve, so that the gap between the tip of the plunger 13b and the other end of the swing arm 6 (between the cam surface 7b of the swing cam 7 and the roller 12) is always zero. It is supposed to be.

  As shown in FIG. 1, each of the swing cams 7 has a substantially rectangular shape with the same shape, and a substantially U-shaped fitting groove 7 a that fits to the outer peripheral surface of the support shaft 14 is formed on the base end side. Thus, the support shaft 14 is supported so as to be swingable through the fitting groove 7a. The cam surface 7b is formed on the lower surface of each swing cam 7, and a base circle surface on the base end side, a ramp surface extending in an arc from the base circle surface to the cam nose portion 7c, and the lamp A lift surface that is continuous from the surface to the top surface of the maximum lift that the cam nose portion 7c has is formed, and the base circle surface, the ramp surface, the lift surface, and the top surface are in a swing position of the swing cam 7. Accordingly, the outer peripheral surface of the needle roller 12 of each swing arm 6 comes into contact with the displaced position.

  Each swing cam 7 has a swing direction in which the cam surface 7b moves toward the lift surface and opens the intake valve 3 in a direction opposite to the rotation direction of the cam shaft 4.

  Further, on the cam nose portion 7c side of the swing cam 7, a pin hole 7e through which a connecting pin 17 connected to the other end portion of a link rod 16 described later is inserted is formed in both side surface directions.

  As shown in FIG. 1, the transmission mechanism 8 includes a rocker arm 15 disposed below the camshaft 4 along the engine width direction, the other end portion 15 b of the rocker arm 15, and the cam nose portion 7 of the rocking cam 7. And a pair of link rods 16 linked to each other.

  As shown in FIGS. 1 and 6, the rocker arm 15 is formed so that the entire side surface is substantially linear, and its vertical width gradually decreases from the one end portion 15a side to the other end portion 15b side. And an elongated space portion 15c cut out from the substantially longitudinal center to the other end portion 15b side.

  A substantially U-shaped recess 18 that is slidably fitted to a control cam 26, which will be described later, is formed at the lower portion of the rocker arm one end 15a, while the other end 15b is interposed via the space 15c. The pin holes 15d and 15d through which the connecting pins 19 are inserted are formed in the lateral direction of the respective end portions.

  On the other hand, the concave portion 18 has an inner surface on the bottom portion 18 a side formed in a substantially semicircular arc shape along the outer shape of the control cam 26, an opening end 18 b is directed downward, and an inner diameter of the control cam 26. It is formed slightly larger than the outer diameter. The rocker arm 15 has a swing fulcrum on one end 15a side through the recess 18 fitted to each control cam 26, and the entire other end 15b swings up and down. Yes.

  In addition, a roller 20 with which the drive cam 5 rolls is rotatably provided via a roller shaft 20a in the space 15c at a substantially central position in the longitudinal direction of the rocker arm 15.

  Further, the rocker arm 15 is provided with a compression coil spring 21 as an urging member so that the inner surface of the recess 18 on the bottom 18 a side is always in elastic contact with the outer periphery of the control cam 26. The compression coil spring 21 has a lower end fixedly supported on the upper end of the cylinder head 1 and an upper end elastically contacting the lower surface of the rocker arm other end 15b.

  Each of the link rods 16 is integrally formed by press molding, the central part is bent into a substantially U-shaped cross section, and the upper and lower ends 16a, 16b are formed in a bifurcated shape. The link rod 16 is disposed so that the bifurcated one end portion 16a is sandwiched from the outside by the bifurcated other end portion 15b of the rocker arm 15, and the one end portion 16a is bored from the lateral direction. It is rotatably connected to the other end 15b of the rocker arm 15 through a connecting pin 19 inserted through the pin hole. On the other hand, each other end portion 16b is rotatably connected to the cam nose portion 7c side of each swing cam 7 through the connecting pin 17 inserted through a pin hole penetratingly formed in the lateral direction.

  The connecting pins 17 and 19 are prevented from coming out of the pin holes by snap rings or the like fitted to both ends.

  Accordingly, the center X of the support shaft 14, the center of the connecting pin 17 that is the connecting portion between the swing cam 7 and the link rod 16, and the connecting pin 19 that is the connecting portion between the link rod 16 and the rocker arm 15 are provided. The center and the axis Q which is the center of rotation of the control cam 23 are connected in a substantially U-shape, so that the whole is a four-bar linkage mechanism.

  As shown in FIGS. 5 and 6, the control mechanism 9 is integrally fixed to the control shaft 22 arranged along the longitudinal direction of the engine parallel to the lower position of the camshaft 4 and the control shaft 22. A control cam 23 serving as a rocking fulcrum of the rocker arm 15 and an actuator (not shown) for controlling the rotation of the control shaft 22 are provided.

  The control shaft 22 is formed to have a relatively large diameter, and is rotatably supported by a bearing portion (not shown) at a predetermined position before and after the engine, and a portion located substantially in the center of each cylinder has a small diameter. The small diameter portion is formed as the control cam 23. That is, a part of the control shaft 22 is cut out in the circumferential direction, and a small-diameter control cam 23 is formed in the remaining part.

  The control cam 23 is formed in a columnar shape having a diameter smaller than the outer diameter of the control shaft 22, and its shaft center Q is eccentrically arranged with a relatively large amount of eccentricity α from the shaft center P of the control shaft 22. The control cam 22 is arranged on the inner side without projecting outward from the outer peripheral surface of the control shaft 22. Therefore, the control cam 23 is integrally provided on the control shaft 22 in a crank shape.

  The actuator includes an electric motor fixed to the rear end of the cylinder head 1 and a speed reducer such as a ball screw mechanism that transmits the rotational driving force of the electric motor to the control shaft 22.

  The electric motor is constituted by a proportional DC motor, and is driven by a control signal from a controller (not shown) that detects the operating state of the engine. This controller includes various sensors such as a crank angle sensor that detects the engine speed, an air flow meter that detects the intake air amount, a water temperature sensor that detects the engine water temperature, and a potentiometer that detects the rotational position of the control shaft 22. The detection signal is fed back to detect the current engine operating state by calculation or the like, and a control signal is output to the electric motor.

  Hereinafter, the operation of the present embodiment will be described. First, when the drive cam 5 rotates in the direction of the arrow along with the rotation of the camshaft 4, the roller 20 of the rocker arm 15 is pressed downward in the lift region, so that the rocker arm 15 uses the control cam 23 of the one end 15a as a fulcrum. The other end portion 15 b side swings downward and pushes down the cam nose portion 7 c side of the swing cam 7 via the link rod 16. As a result, the intake valve 3 is opened against the spring force of the valve spring 10 via the swing arm 6, and the swing cam 7 is moved by the spring force of the valve spring 10 in the base circle region of the drive cam 5. When the base circle surface of the cam surface 7b comes into contact with the roller 12 by swinging clockwise, the closing operation is performed.

  Then, for example, in a low rotation range such as during idling operation of the engine, the electric motor is rotationally driven by a control signal from the controller, and this rotational torque is transmitted to the control shaft 22 via the speed reducer. Is rotated by a predetermined amount in one direction as shown in FIGS.

  Accordingly, as shown in FIGS. 1 and 2, the control cam 23 rotates in one direction, the axis Q rotates around the axis P of the control shaft 22, and the outer end side is as shown in the figure. To the right lower direction from the axis P of the control shaft. As a result, the entire rocker arm 15 is shifted to the right, and each swing cam 7 is forcibly pulled up on the cam nose portion 7 c side via the link rod 16.

  Therefore, when the drive cam 5 is rotated by the camshaft 4 and the other end 15b of the rocker arm 15 is pulled down via the link arm 16, the swing cam 7 is moved via the link rod 16 as shown in FIGS. However, the amount by which the cam surface 7b pushes the roller 12 of the swing arm 6 becomes small, and the valve lift amount becomes the smallest.

  Therefore, in the low speed region of such an engine, the valve lift amount L of each intake valve 3 is minimized as shown in FIG. 7, the opening timing (IVO) of each intake valve 3 is delayed, and the valve overlaps with the exhaust valve. This IVO is only slightly delayed just before the top dead center of the piston. Further, the closing timing (IVC) of the intake valve 3 is sufficiently early.

  For this reason, improvement of fuel consumption and stable rotation of the engine can be obtained by reducing pump loss and improving combustion of the engine.

  Further, when the engine shifts to the high engine speed range, the control shaft 22 controls the control shaft 22 as shown in FIGS. 3 and 4 when the electric motor rotates in reverse by the control signal from the controller and rotates the speed reducer in the same direction. The cam 23 is rotated in the other direction, and the shaft center Q of the control cam 23 is moved from the shaft center P of the control shaft 22 to a direction almost directly above (camshaft 4 side). For this reason, as shown in the figure, the rocker arm 15 now moves in the upper left direction. Therefore, the cam nose portion 7c of the swing cam 7 is pressed downward via the link rod 16 by the other end portion 15b of the rocker arm 15, and the entire swing cam 7 is rotated counterclockwise by a predetermined amount.

  Therefore, the contact position of the cam surface 7b with the roller 12 of the swing arm 6 of the swing cam 7 moves to the cam nose portion 7c side (lift portion side). Therefore, as shown in FIG. 4, when the drive cam 5 rotates during the opening operation of the intake valve 3 and the other end 15b of the rocker arm 15 is pulled down via the link arm 16, the lift amount with respect to the swing arm 6 is as follows. Become the largest.

  Therefore, in such a high rotation region, as shown in FIG. 7, the valve lift amount L1 of the intake valve 3 becomes maximum, the opening timing of the intake valve 3 becomes earlier, and the valve overlap with the exhaust valve becomes larger. The closing time is delayed. As a result, the intake charging efficiency is improved and a sufficient output can be secured.

  Further, when the operation state is shifted to the low rotation range, the intake valve 3 becomes the minimum valve lift L by the above-described action. Here, the rocking fulcrum (the center Q of the control cam) on the one end portion 15a side of the rocker arm 15 1) and 2), as shown in FIGS. 1 and 2, the link rod is rotated via the rocker arm 15 by rotating in the clockwise direction in the figure as compared with the case of controlling the maximum valve lift L1 (FIGS. 3 and 4). Since 16 is rotated in the clockwise direction, the lift peak phase of the minimum valve lift L shifts to the advance side as shown by the arrow in FIG. Therefore, the change in the opening timing (IVO) of the intake valve 3 is smaller near the piston top dead center (TDC), but the change in the closing timing (IVC) is larger than that in the case of the maximum valve lift L1. Be controlled.

  Accordingly, since the phase of the opening timing (IVO) of the intake valves 3 and 3 can be controlled near the top dead center of the piston, the valve overlap with the exhaust valve during the small valve lift control of the intake valves 3 and 3 is prevented. It becomes possible to control appropriately. As a result, an increase in residual gas is suppressed, and it becomes possible to prevent deterioration of combustion.

  In addition, the lift is controlled continuously from the minimum lift control to the maximum lift control, or from the maximum lift control to the minimum lift control, and controlled to any lift amount and operating angle via the control shaft 22 according to the engine operating state. Can do.

  In this embodiment, the rocker arm 15 is supported by the control cam 23 so that the one end portion 15a is swingable, and the central position is pressed by the drive cam 5 via the roller 20 and swings. The valve 3 is opened and closed, and the posture of the control cam 23 of the control shaft 22 is changed by changing the rotational position so that the lift amount of the intake valve 3 is changed. It becomes possible to increase the amount of change in lift.

  In addition, since the load of the link portion between the one end portion 15a of the rocker arm 15 and the control cam 23 can be reduced by the unique configuration, the gap between the inner peripheral surface of the recess 18 and the outer peripheral surface of the control cam 23 is reduced. Sliding friction can be reduced. As a result, the load torque of the actuator can be reduced. Further, since the outer diameter of the control cam 23 can be reduced, the friction between the recess 18 of the rocker arm 15 and the control cam 23 can be reduced in this respect as well.

  Further, as described above, the rocker arm 15 is configured such that the driving cam 5 presses the central roller 20 through the pivot point on the one end 15a side to swing the swing cam 7, and a load is applied in the middle. Since there is no balance structure for reversing the rotation, high rigidity is obtained, and thereby it is possible to reduce irregular motion of the intake valve 3.

  Since one end 15a of the rocker arm 15 is provided with a recess 18 that is slidably fitted to the control cam 23, the one end 15a of the rocker arm 15 is assembled to the control cam 23 by using the recess 18 It is only necessary to fit in the outer radial direction of the control cam 23 from the opening end 18b side. Therefore, the assembling work of the rocker arm 15 becomes extremely easy, and the working efficiency can be improved and the cost can be reduced.

  Further, since the compression coil spring 21 is elastically mounted between the pivot 20 of the other end portion 15b of the rocker arm 15 and the roller 20, the action of the spring force on the control cam 23 can be suppressed, and the frictional force can be suppressed. Increase can be reduced. Even if the load is concentrated on the roller 20, there is no problem because the friction coefficient is small.

  Further, since the drive cam 5, the rocker arm 15, the link rod 16 and the swing cam 7 are arranged on substantially the same plane without being offset in the axial direction, the rocker arm 15 in the cam shaft direction during the swing is arranged. Fall can be reduced.

  Further, since the drive cam 5, the rocker arm 15, the link rod 16 and the swing cam 7 (support shaft 14) have a U-shaped four-link structure, the apparatus can be made compact.

  In addition, since the control cam 23 is arranged in a crank shape with respect to the control shaft 22, the amount of eccentricity of the center Q with respect to the axis P of the control shaft 22 can be increased. As a result, the amount of eccentricity of the rocking fulcrum (center) Q of the rocker arm 15, that is, the amount of change in the valve lift amount, operating angle, and lift peak phase of the intake valves 3 and 3 can be increased.

  Further, since the spring force of the valve spring 10 and the drive force from the drive cam 5 are distributed to the rocker arm 15 and the link rod 16 in a well-balanced manner, it is possible to suppress the occurrence of concentrated stress and deformation at each part.

  Since the control cam 23 is disposed on the one end portion 15a side of the rocker arm 15, the spring force of the valve spring 10 is received by the drive cam 5, so that the contact load between the recess 18 and the control cam 23 is increased. Can be reduced.

  Since the shape of the inner peripheral surface of the recess 18 is substantially the same as the outer shape of the control cam 23, the contact area between the two is increased, so that the contact load is dispersed and the generation of concentrated load can be prevented.

[Second Embodiment]
FIG. 8 shows a second embodiment of the present invention, the basic structure of which is the same as that of the first embodiment, except that the support shaft 14 for swingably supporting the swing cam 7 is a control shaft 22. The arm 24 is fixed to the outer peripheral surface of the control shaft 22, and the control cam 23 is provided at the tip of the arm 24.

  That is, the control shaft 22 is connected to an actuator (not shown) composed of the electric motor and the ball screw mechanism described above at one end, and a substantially U-shaped fitting groove 7a of each swing cam 7 on the outer periphery. Are fitted to serve as a swing fulcrum of the swing cam 7.

  The arm 24 is formed in a plate shape having a predetermined length and a substantially uniform width, and a first fixing hole 24c fixed to the outer peripheral surface of the control shaft 22 is formed through the one end 24a. The part 24b is formed with a second fixing hole 24d through which the substantially cylindrical control cam 23 is inserted and fixed. Therefore, the control shaft 22, the arm 24 and the control cam 23 are connected in a crank shape.

  Therefore, when the control shaft 22 rotates in the left-right direction, the axis Q of the control cam 23 is placed on an arc around the axis P of the control shaft 22 as indicated by the arrow in the figure via the arm portion 24. Swing.

  Accordingly, when a control current is output from the controller to the actuator in accordance with a change in the engine operating state and the control shaft 22 rotates in a predetermined direction, the control cam 23 moves on the arc locus via the arm 24, and the first As in the embodiment, the lift amount of the intake valve 3 is variably controlled by changing the swinging posture of the rocker arm 15.

  According to the present embodiment, since the control shaft 22 can also be used as the support shaft 14 by the arm 24, it is possible to reduce the number of parts, thereby facilitating manufacturing work and assembly work. Cost reduction can be achieved.

  The present invention is not limited to the configuration of each of the embodiments described above, and can be applied to the exhaust valve side, and the size and the like of the rocker arm 15 can be arbitrarily determined according to the specifications and size of the device. It is also possible to change.

  In addition, the concave portion 18 of the rocker arm one end portion 15a in the first embodiment is formed in a C shape, and a two-sided width portion is formed on the side portion in the axial direction of the portion where the concave portion 18 of the control shaft 22 is fitted. During assembly, it is possible to prevent the control cam 23 from inadvertently coming out of the control shaft 22 by inserting the concave portion 18 from the two-surface width portion and moving in the axial direction.

It is a principal part front view at the time of the minimum lift control of the variable valve apparatus in 1st Example. It is a principal part front view which shows the operation state at the time of valve opening at the time of the minimum lift control of the variable valve operating apparatus. It is a principal part front view which shows the operation state at the time of valve closing at the time of the maximum lift control of the variable valve operating apparatus. It is a principal part front view which shows the operation state at the time of valve opening at the time of the maximum lift control of the variable valve operating apparatus. It is a principal part side view of the variable valve operating apparatus. It is a principal part top view of the variable valve operating apparatus. It is a characteristic view of the valve lift of the intake valve in the variable valve operating apparatus. It is a principal part front view of the variable valve apparatus of 2nd Example.

Explanation of symbols

1 ... Cylinder head 3 ... Intake valve (engine valve)
DESCRIPTION OF SYMBOLS 4 ... Drive shaft 5 ... Drive cam 7 ... Swing cam 7b ... Cam surface 8 ... Transmission mechanism 9 ... Control mechanism 15 ... Rocker arm 15a ... One end part 15b ... Other end part 16 ... Link rod 18 ... Recessed part 18a ... Recessed part bottom face 18b ... Open end 21 ... Compression coil spring (biasing member)
22 ... Control shaft 23 ... Control cam X ... Drive shaft axis Y ... Drive cam shaft center P ... Control shaft axis Q ... Control cam shaft center

Claims (7)

A swing cam that is swingably supported by the support shaft and that opens and closes the engine valve by swinging;
A control cam provided rotatably,
A rocker arm having one end side swingably supported by the control cam;
A link rod that links the other end of the rocker arm and the swing cam, and moves at least in the valve opening direction of the engine valve in accordance with the swing of the rocker arm;
A driving cam that abuts a portion between one end side and the other end side of the rocker arm and presses the rocker arm by applying a rotational driving force from a crankshaft;
A variable valve operating apparatus for an internal combustion engine, comprising: The variable valve operating apparatus for an internal combustion engine according to claim 1,
A substantially U-shaped fitting portion that fits into the control cam is formed on one end side of the rocker arm, and the bottom side of the fitting portion is urged toward the outer peripheral surface of the control cam. A variable valve operating device for an internal combustion engine. The variable valve operating apparatus for an internal combustion engine according to claim 2,
An urging member for urging the bottom side of the fitting portion of the rocker arm in the direction of the outer peripheral surface of the control cam is provided, and the urging force is applied by elastically contacting the urging member with a predetermined portion of the rocker arm. A variable valve operating device for an internal combustion engine characterized by the above. The variable valve operating apparatus for an internal combustion engine according to claim 1,
2. A variable valve operating apparatus for an internal combustion engine, wherein a roller is provided at a portion of the rocker arm where the drive cam abuts. The variable valve operating apparatus for an internal combustion engine according to claim 1,
A variable valve operating apparatus for an internal combustion engine, wherein one end of an arm is rotatably provided on the support shaft, and the control cam is provided on the other end of the arm. A swing cam that is swingably supported by the support shaft and that opens and closes the engine valve by swinging;
A control cam provided rotatably,
A rocker arm having one end side swingably supported by the control cam;
A link rod that links the other end side of the rocker arm and the swing cam, and moves at least in the valve opening direction of the engine valve according to the swing of the rocker arm;
A driving cam that abuts a portion between one end side and the other end side of the rocker arm and presses the rocker arm by applying a rotational driving force from a crankshaft;
With
The center of the support shaft, the center of the link between the swing cam and the link rod, the center of the link between the link rod and the rocker arm, and the center of rotation of the control cam are connected in a substantially U-shape. A variable valve operating device for an internal combustion engine, characterized in that A swing cam that is swingably supported by the support shaft and that opens and closes the engine valve by swinging;
A control cam provided rotatably,
A rocker arm having one end side swingably supported by the control cam;
A link rod that links the other end side of the rocker arm and the swing cam, and moves at least in the valve opening direction of the engine valve according to the swing of the rocker arm;
A driving cam that abuts a portion between one end side and the other end side of the rocker arm and presses the rocker arm by applying a rotational driving force from a crankshaft;
With
A variable valve operating apparatus for an internal combustion engine, wherein the rocker arm, the link rod, and the swing cam constitute a four-bar linkage mechanism.

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