JP4711999B2 - Variable valve mechanism - Google Patents

Description

  The present invention relates to a variable valve mechanism that changes the opening / closing amount of a valve stepwise in accordance with the operating condition of an internal combustion engine.

  In this type of variable valve mechanism, an inner arm 83 having an input roller 84 that rotatably contacts the rotating cam 81, as in the variable valve mechanism 80 of the first conventional example shown in FIG. A rocker arm 82 composed of an outer arm 85 arranged on the outside and abutting against the valve 7 is provided, and a connecting pin 86 provided on the rotating shaft of the input roller 84 is connected to the connecting pin 86 by a hydraulic type or the like. By connecting the inner arm 83 and the outer arm 85 so as not to be able to swing relative to each other by being displaced between a position straddling between the inner arm 83 and the outer arm 85 and a position not straddling the inner arm 83 and the outer arm 85 by the drive mechanism 87 of FIG. There is a switch between the state and the unconnected state in which the connection is released, and the opening / closing amount of the valve 7 is changed by the switch (Patent Document 1).

In addition, as in the variable valve mechanism 90 of the second conventional example shown in FIG. 6, a rocker arm 92 including an inner arm 93 and an outer arm 95 arranged on the outer side is provided. The provided connecting pin 96 is displaced between a position straddling between the inner arm 93 and the outer arm 95 and a position not straddling by a hydraulic drive mechanism 97 provided at the swing center portion of the inner arm 93. In some cases, switching between the connected state and the unconnected state is performed to change the opening / closing amount of the valve 7 (Patent Document 2).
US Patent Application Publication No. 2005/132990 US Patent Application Publication No. 2004/74459

  In either case of the conventional examples 1 and 2, the drive mechanisms 87 and 97 must be installed adjacent to the connection pins 86 and 96 because they directly drive the connection pins 86 and 96. Therefore, with these conventional examples 1 and 2, the degree of freedom in designing the variable valve mechanism is small. For example, for functional reasons, the connecting part that connects both arms such as a connecting pin so as to be disengaged is provided. Although the drive mechanism is desired to be provided on the rotation shaft of the input roller, the drive mechanism cannot be dealt with in the case where it is provided only at the center of the swinging due to structural reasons.

  Accordingly, it is an object of the present invention to provide a connecting portion for connecting both arms so as to be disengaged and a drive mechanism for switching connection and disengagement by the connecting portion.

To achieve the above Symbol purpose of the variable valve mechanism of the present invention, a rocker arm and an output arm is pivotably supported side by side on the same axis line, which abuts on the input arm and the valve abutting the rotating cam And a switching mechanism that switches between a connected state in which the input arm and the output arm are connected to each other so as not to be able to swing relative to each other, and a disconnected state in which the connection is released. In the variable valve mechanism for changing the opening / closing amount of the input arm, the output arm is configured to be displaceable between an adjacent position adjacent to the input arm and a separated position spaced apart from the input arm in the axial direction, and the switching mechanism The drive mechanism that drives the output arm in the axial direction, and the input arm and the output arm are connected so as not to be relatively swingable when the output arm is displaced to the adjacent position. , When said output arm is displaced in the separated position is constituted and a connecting portion for releasing the connection, the input arm and the output arm, the lash adjuster having a through hole in the tip portion the The rocker shaft is supported by the rocker shaft supported on the axis by being inserted into the through hole so as to be able to swing .

  Here, the position where the drive mechanism and the connecting portion are provided is not particularly limited, but the rear end portion (base end portion) is supported so as to be swingable, the intermediate portion in the length direction is in contact with the rotating cam, and the tip portion is a valve. When a drive mechanism is provided inside or outside the base end of the rocker arm that contacts the front end and a connecting portion is provided at the front end or the middle in the longitudinal direction, or the longitudinal middle is supported so as to be able to swing, and the rear end A drive mechanism is provided outside or at the inside of the lengthwise intermediate portion of the rocker arm where the tip abuts against the rotary cam and the tip end abuts on the valve, and at the tip, rear end, or lengthwise intermediate portion. The case where a connection part is provided etc. is mentioned as an example.

As described above, the support structure of the rocker arm is supported on the axis line by inserting the input arm and the output arm into the through hole of the lash adjuster having a through hole at the tip. The reason why the rocker shaft is supported so as to be able to swing is that there is a lash adjuster so that adjustment of the valve clearance becomes unnecessary. In addition, if a lash adjuster having a through hole at the tip is used as described above, the arm is less likely to tilt than when a general upper hemispherical lash adjuster that simply mounts the arm is used. In addition, the use of the rocker shaft in this way is convenient for driving the output arm in the axial direction.

  At this time, the configuration of the drive mechanism and its peripheral portion is not particularly limited, but the rocker shaft is configured to be displaceable in the axial direction, and the input arm is in the axial direction of the rocker shaft with respect to the input arm. Relative to the rocker shaft, the output arm is configured not to be relatively displaceable in the axial direction with respect to the rocker shaft, and the drive mechanism includes the rocker shaft provided inside the input arm. It is preferable to include a hydraulic chamber that is driven in the axial direction by hydraulic pressure, and an oil passage that is provided via the inside of the lash adjuster and the rocker shaft and that supplies the hydraulic pressure to the hydraulic chamber.

The variable valve mechanism according to the present invention includes a rocker arm including an input arm that abuts on a rotating cam and an output arm that abuts a valve, which are supported on the same axis so as to be swingable, the input arm, and the output And a switching mechanism for switching between a connected state in which the arms are connected to each other so as not to be able to swing relative to each other and a non-connected state in which the connection is released. The switching amount of the valve can be changed by the switching. In the variable valve mechanism, the output arm is configured to be displaceable between an adjacent position adjacent to the input arm and a separated position spaced apart from the input arm in the axial direction, and the switching mechanism is configured to displace the output arm. When the drive mechanism for driving in the axial direction and the output arm are displaced to the adjacent position, the input arm and the output arm are connected so as not to be able to swing relative to each other, and the output arm When displaced serial spaced position is constituted and a connecting portion for releasing the connection, the input arm, the contact portion between the rotating cam, the input roller rotatably abuts on the rotary cam The connecting portion includes a connecting projection in which an end portion of a roller shaft that pivotally supports the input roller protrudes from the side surface of the input arm toward the output arm, and the output arm provided on the output arm. And a connecting hole into which the connecting protrusion is inserted when displaced to the adjacent position, and the connecting protrusion is removed when displaced to the separated position .

Further, the rocker arm is not particularly limited, and examples thereof include the following (1) and (2).
(1) One rocker arm is in contact with a pair of valves and drives the pair of valves (2) One rocker arm is in contact with only one valve and drives the one valve

  In the case of (1), although the output arm is not particularly limited, the output arm is provided with an output shaft extending in the axial direction across the pair of valves at the contact portion with the pair of valves, The output shaft is configured not to be relatively displaceable in the axial direction with respect to the pair of valves, and relative to the main body portion of the output arm excluding the output shaft, relative to the output shaft in the axial direction. It is preferable to allow.

The configuration of the one rocker arm is not particularly limited, but the following (i) and (ii) are given as examples.
(I) A pair of output arms arranged on both sides in the axial direction of one input arm (ii) A structure in which one output arm is arranged only on one side in the axial direction of one input arm

  The change in the valve opening / closing amount in the variable valve mechanism described above is not particularly limited, but includes a driving state in which the valve is driven according to the rotation of the rotating cam, and a driving stop state in which the driving is completely stopped. Or when switching between a high lift state in which the valve is opened and closed with a relatively large lift amount according to the rotation of the rotating cam and a low lift state in which the valve is opened and closed with a relatively small lift amount. Take as an example.

  According to the present invention, the drive mechanism does not directly drive the connecting portion as in the conventional examples 1 and 2, but connects and releases both arms by the connecting portion by driving the output arm. For this reason, the driving mechanism can be installed at any position where the driving force can be transmitted to the output arm, even if the driving force cannot be transmitted directly to the connecting portion. Therefore, the drive mechanism can be provided away from the connecting portion within the range of the position where the drive force can be transmitted to the output arm.

  The variable valve mechanism 9 of the present invention includes a rocker arm 20 including an input arm 21 that contacts the rotating cam 10 and an output arm 26 that contacts the valve 7, which are supported on the same axis so as to be swingable. 21 and the output arm 26 are configured to include a switching mechanism 40 that switches between a connected state in which the output arm 26 and the output arm 26 are connected to each other so as not to swing relative to each other, and a disconnected state in which the connection is released. Change the amount.

  Specifically, the input arm 21 and the output arm 26 are relatively displaced in the axial direction H on the axis line by being inserted into the support hole 31 of the lash adjuster 30 provided with a support hole 31 having a through-hole shape at the tip. The rocker shaft 20x is supported so as to be swingable. Here, the input arm 21 allows relative displacement in the axial direction H of the rocker shaft 20x with respect to the input arm 21, and the output arm 26 is configured to be incapable of relative displacement in the axial direction H with respect to the rocker shaft 20x. Yes. Accordingly, the output arm 26 is displaced in the axial direction H together with the rocker shaft 20x, so that the output arm 26 is located between the adjacent position B adjacent to the input arm 21 and the separated position A separated from the input arm 21 in the axial direction H. Displaceable. Further, the input arm 21 is provided with an input roller 23 which is in contact with the rotating cam 10 so as to be rotatable at a contact portion with the rotating cam 10.

  The switching mechanism 40 connects the input arm 21 and the output arm 26 so as not to swing relative to each other when the output arm 26 is displaced to the adjacent position B when the output arm 26 is displaced to the adjacent position B. When the output arm 26 is displaced to the separation position A, it includes a connecting portion 46 that releases the connection. The drive mechanism 41 is provided in the input arm 21 through a hydraulic chamber 42 that hydraulically drives the rocker shaft 20x in the axial direction H, and a hydraulic pressure provided through the lash adjuster 30 and the rocker shaft 20x. An oil passage 43 that supplies hydraulic pressure to the chamber 42 is included. The connecting portion 46 includes a connecting projection 47 in which an end portion of the roller shaft 23x that pivotally supports the input roller 23 protrudes from the side surface of the input arm 21 toward the output arm 26, and the arm provided adjacent to the output arm 26. When arranged at the position B, the connecting projection 47 is inserted, and when arranged at the separated position A, the connecting projection 47 is extracted and removed.

  The variable valve mechanism 9 shown in FIGS. 1 to 3 of the present embodiment is a mechanism that changes the opening / closing amount of the valve stepwise in accordance with the operating state of the internal combustion engine. In this embodiment, the variable valve mechanism 9 is provided only for half of the cylinders 5 (not shown), and each variable valve mechanism 9 is provided for each cylinder 5. The two intake valves 7 are driven. The variable valve mechanism 9 includes a rotary cam 10 that rotates according to the rotation of the internal combustion engine, a rocker arm 20 that is swingably interposed between the rotary cam 10 and the valve 7, and biases the valve 7 in the opening direction. The valve spring 50 for urging the valve 7 in the closing direction and the switching mechanism 40 for switching the state of the rocker arm 20 are configured to drive the valve 7 according to the rotation of the rotary cam 10 and the driving thereof. Is switched to the drive stop state in which the operation is stopped. In addition, in FIG. 1, illustration of the rotating cam 10 is abbreviate | omitted for convenience.

  The rotary cam 10 is formed on a camshaft 10x that is rotationally driven as the internal combustion engine operates, and includes a base circle portion 11 that is a basic portion and a cam nose 12 that protrudes from the base circle portion 11. Has been. The rotating cam 10 is disposed above the rocker arm 20, and a cam surface that presses the input roller 23 of the rocker arm 20 is formed on the outer peripheral surface of the rotating cam 10.

  The rocker arm 20 is a two-valve integrated arm that drives the two valves 7 simultaneously. The rocker arm 20 contacts the rotary cam 10 and the input arm 21 that are supported on the same axis line so as to be swingable. It consists of a pair of output arms 26 in contact.

  Specifically, the input arm 21 includes a fulcrum hole 22 having a through hole for pivotally supporting the rocker shaft 20x at the base end portion, and an input roller 23 that rotatably contacts the rotary cam 10 at the distal end portion. I have. The input roller 23 is supported via a bearing 24 on a roller shaft 23x extending in the axial direction H, which is the length direction of the axis. Between the input arm 21 and the cylinder head 6, a lost motion spring 25 that biases the input arm 21 toward the rotary cam 10 is attached. And the displacement in the axial direction H with respect to the cylinder head 6 of the input arm 21 is regulated by attaching the lost motion spring 25.

  Further, the output arm 26 is disposed on each side of the input arm 21, and has a fulcrum hole 27 in the form of a through hole for being pivotally supported by the rocker shaft 20 x at the base end portion. The two output arms 26 are provided with a single output shaft 28 that extends in the axial direction H across the output arms 26, and both end portions 28 e of the output shafts 28 are stems of the pair of valves 7. The end 7e is in contact with each other. Specifically, a cap-shaped pad 8 is attached to each stem end 7e, and the output shaft 28 is in contact with the upper surfaces of both pads 8 so as to straddle between the valves 7. The output shaft 28 allows relative displacement in the axial direction H with respect to the output shaft 28 with respect to the main body portion of the output arm 26 excluding the output shaft 28. On the other hand, in the output shaft 28, the diameters of the end portions 28 e on both sides contacting the valve 7 are smaller than those of the middle portion 28 c, and the side surfaces of the pads 8 on both sides are formed on both end surfaces of the middle portion 28 c. , The relative displacement of the output shaft 28 in the axial direction H with respect to the valve 7 is regulated. The output shaft 28 can be replaced with one having a different length, and can easily be adapted to other internal combustion engines having different valve pitches.

  The rocker arm 20 described above is supported between the rotary cam 10 and the valve 7 as follows. That is, on both sides of the rocker arm 20 straddling the rocker arm 20 in the axial direction H, an upper ring type hydraulic lash adjuster 30 provided with a support hole 31 in the form of a through hole is provided at the upper part (tip part). . The rocker shafts 20x different from each other are inserted into the support holes 31 of the lash adjusters 30 so as to be relatively displaceable in the penetration direction of the support holes 31, and one rocker shaft 20x is connected to the fulcrum hole 22 of the input arm 21. By inserting across the fulcrum hole 27 of one output arm 26 and inserting the other rocker shaft 20x across the fulcrum hole 22 of the input arm 21 and the fulcrum hole 27 of the other output arm 26, As described above, the input arm 21 and the output arm 26 are supported on the same axis line so as to be swingable. The input arm 21 is inserted into the fulcrum hole 22 of the input arm 21 so that the rocker shaft 20x can be relatively displaced in the penetrating direction of the fulcrum hole 22, so that the axial direction H relative to the input arm 21 is inserted into the rocker shaft 20x. Relative displacement to is allowed. On the other hand, after the rocker shaft 20x is inserted into the fulcrum hole 27 of the output arm 26, the output arm 26 is integrated with the rocker shaft 20x by being coupled by press fitting. Accordingly, the output arm 26 is integrally displaced in the axial direction H together with the rocker shaft 20x, so that the adjacent position B adjacent to the input arm 21 and the separated position A that is separated from the input arm 21 in the axial direction H. It can be displaced between.

  The switching mechanism 40 is a mechanism that switches between a connected state in which the input arm 21 and the output arm 26 are connected to each other so as not to be able to swing relative to each other, and a disconnected state in which the connection is released. 9 performs switching between the above-described driving state and driving stop state by the switching. The switching mechanism 40 connects the output arm 26 to the input arm 21 when the output arm 26 is disposed at the adjacent position B when the output arm 26 is disposed in the adjacent position B. When 26 is arranged at the separation position A, it includes a connecting portion 46 that releases the connection.

  The drive mechanism 41 is brought into a non-connected state by driving the output arm 26 to the separation position A with hydraulic pressure, and is brought into a connected state by driving the output arm 26 to the adjacent position B with the restoring force of the spring loosened. Specifically, the drive mechanism 41 is configured to disengage the rocker shaft 20x provided inside the input arm 21 by opening the openings on both sides of the fulcrum hole 22 of the input arm 21 from both sides by both rocker shafts 20x. A hydraulic chamber 42 that is hydraulically biased toward the A side, an oil passage 43 that supplies hydraulic pressure to the hydraulic chamber 42 that is provided via the cylinder head 6, the lash adjuster 30, and the rocker shaft 20x, and the output arm 26 And a spring 44 that is interposed between the lash adjuster 30 and urges the output arm 26 toward the adjacent position B with a restoring force.

  The connecting portion 46 includes a connecting projection 47 in which an end portion of the roller shaft 23x supporting the input roller 23 projects from the side surface of the input arm 21 toward the output arm 26, and the output arm 26 penetrating the output arm 26. A connecting projection 47 is inserted when the connector 26 is disposed at the adjacent position B, and a through hole-shaped connecting hole 48 is formed through which the connecting projection 47 is removed when disposed at the separated position A. ing.

  The state of the variable valve mechanism 9 described above will be described below separately for (1) when the internal combustion engine is rotating at a low speed and (2) when the internal combustion engine is rotating at a high speed.

(1) At the time of low speed rotation of the internal combustion engine At this time, as shown in FIGS. 1A and 2A, when the hydraulic pressure in the hydraulic chamber 42 increases, the hydraulic pressure in the output arm 26 is increased by the rocker shaft. It is driven to the separated position A against the restoring force of the spring 44 integrally with 20x. At this time, the connection protrusion 47 is removed from the connection hole 48 to be in a non-connected state, and the input arm 21 and the output arm 26 can be relatively swung. Therefore, at this time, as shown in FIGS. 3A and 3B, the input arm 21 swings independently of the output arm 26 according to the rotation of the rotary cam 10. Therefore, in this non-connected state, the valve 7 is in a drive stop state, and therefore, half of the cylinders 5 in which the variable valve mechanism 9 is installed are not inhaled, and only the remaining half of the cylinders. The internal combustion engine is operated by the output from.

(2) At the time of high-speed rotation of the internal combustion engine At this time, as shown in FIGS. 1B and 2B, the output arm 26 is integrated with the rocker shaft 20x as the hydraulic pressure in the hydraulic chamber 42 decreases. To the adjacent position B by the restoring force of the spring 44. At this time, the connection protrusion 47 is inserted into the connection hole 48 to establish a connection state, and the input arm 21 and the output arm 26 cannot be relatively swung. Therefore, at this time, as shown in FIGS. 3C and 3D, the input arm 21 and the output arm 26 swing integrally with the rotation of the rotary cam 10, and are output by the output shaft 28 of the output arm 26. The valve 7 is driven by being pushed downward. For this reason, in this connected state, intake is also performed to the cylinder 5 in which the variable valve mechanism 9 is installed, and the internal combustion engine is operated by the output from all the cylinders.

  According to the present embodiment, the drive mechanism 41 does not directly drive the connecting portion 46 but drives the output arm 26 to connect and release the input arm 21 and the output arm 26 by the connecting portion 46. Therefore, the drive mechanism 41 can be installed at any position where the drive force can be transmitted to the output arm 26, even if the drive force cannot be transmitted directly to the connecting portion 46. . Therefore, as described above, the drive mechanism 41 can be provided away from the connecting portion 46 toward the proximal end side of the rocker arm 20. Further, by providing the drive mechanism 41 at the base end side of the rocker arm 20 in this way, the disadvantage caused by pulling the oil passage 43 and the hydraulic chamber 42 to the front end side of the rocker arm 20 is eliminated.

  Further, in this embodiment, since there is a lash adjuster 30, it is not necessary to adjust the valve clearance. In addition, since the lash adjuster 30 has a structure that supports the rocker shaft 20x in the upper support hole 31, a general upper hemispherical lash adjuster in which only the rocker arm is mounted is used. The rocker arm 20 is not easily separated from the lash adjuster 30, and the rocker arm 20 is difficult to tilt in the width direction. Furthermore, since the output arm 26 is supported on the rocker shaft 20x so as to be displaceable in the axial direction H together with the shaft, the support structure for supporting the output arm 26 so as to be displaceable in the axial direction H is simple. Has been realized.

  In this embodiment, since the oil passage 43 of the drive mechanism 41 passes through the inside of the hydraulic lash adjuster 30, the oil passage 43 for the switching mechanism 40 and the oil passage for the lash adjuster 30 are used. Therefore, the structure of the variable valve mechanism 9 is simplified.

  It should be noted that the present invention is not limited to the configuration of the embodiment described above, and can be modified and embodied without departing from the spirit of the invention. For example, the following modifications 1 and 2 can be made. May be.

[Modification 1]
By providing the rocker arm 20 with a stopper or the like for limiting the stroke that allows the input arm 21 to swing relative to the output arm 26 in the non-connected state, as shown in FIGS. Even in the connected state, the driving of the valve 7 may not be stopped completely, but the valve 7 may be driven with a lift amount smaller than that in the connected state.

[Modification 2]
In place of the rocker arm 20, as shown in FIG. 4C, an intermediate portion in the longitudinal direction is supported so as to be swingable, and an output arm 62 whose tip is in contact with the valve 7 and a swing shaft of the output arm 62 The rocker arm 60 comprising the input arm 61 provided with the input roller 23 is provided at the rear end thereof, and the connecting portion 46 is provided on the side of the input roller 23. A driving mechanism for driving the output arm 62 in the length direction of the axis may be provided at the swing center portion of 61. At this time, the input roller 23 is pressed and driven from below by the rotating cam 10 provided below the input roller 23.

[Modification 3]
Instead of making the diameters of both end portions 28e of the output shaft 28 smaller than the middle portion 28c, as shown in FIG. It may be recessed. At this time, as in the embodiment, the side surfaces of the pads 8 on both sides abut against the end surfaces on both sides of the middle portion 28c, thereby restricting relative displacement of the output shaft 28 in the axial direction H with respect to the valve 7. The Rukoto.

In an Example, (a) is a perspective view which shows a mode when an input arm and an output arm are a non-connection state, (b) is a perspective view which shows a mode in the case of a connection state. In the same Example, (a) is a plane sectional view showing a state when the input arm and the output arm are in a non-connected state, and (b) is a plan sectional view showing a state in a connected state. In the same embodiment, (a) and (b) are side views showing the state when the input arm and the output arm are not connected, and (c) and (d) are side views showing the state when they are connected. It is. (A) And (b) is a side view which shows the variable valve mechanism of the modification 1, (c) is a side view which shows the variable valve mechanism of the modification 2, (d) is a variable valve mechanism of the modification 3. FIG. It is a perspective view which shows the variable valve mechanism of the prior art example 1. FIG. It is a perspective view which shows the variable valve mechanism of the prior art example 2.

Explanation of symbols

7 Valve 9 Variable valve mechanism 10 Rotating cam 20 Rocker arm 20x Rocker shaft 21 Input arm 23 Input roller 23x Roller shaft 26 Output arm 30 Rush adjuster 40 Switching mechanism 41 Drive mechanism 42 Hydraulic chamber 43 Oil passage 46 Connecting portion 47 Connecting protrusion 48 Connecting Hole A Spacing position B Adjacent position H Axial direction

Claims (3)

A rocker arm including an input arm that abuts against a rotating cam and an output arm that abuts a valve, which are supported on the same axis so as to be able to swing, and the input arm and the output arm are connected to each other so as not to swing relative to each other. In a variable valve mechanism that includes a switching mechanism that switches between a connected state and a non-connected state that releases the connection, and changes an opening / closing amount of the valve by the switching,
The output arm is configured to be displaceable between an adjacent position adjacent to the input arm and a separated position spaced apart from the input arm in the axial direction.
The switching mechanism is configured to connect the input arm and the output arm so as not to be relatively swingable when the output arm is displaced to the adjacent position when the output arm is displaced to the adjacent position. A connecting portion for releasing the connection when the output arm is displaced to the separated position ,
The input arm and the output arm are swingably supported by a rocker shaft supported on the axis line by being inserted into the through hole of a lash adjuster having a through hole at a front portion. A variable valve mechanism characterized by The rocker shaft is configured to be displaceable in the axial direction, the input arm allows relative displacement of the rocker shaft in the axial direction with respect to the input arm, and the output arm is in relation to the rocker shaft. Configured to be relatively undisplaceable in the axial direction,
The drive mechanism is provided inside the input arm, and is provided via a hydraulic chamber that hydraulically drives the rocker shaft in the axial direction, and the hydraulic pressure provided via the lash adjuster and the rocker shaft. The variable valve mechanism according to claim 1 , further comprising an oil passage that supplies the hydraulic pressure to a chamber . A rocker arm including an input arm that abuts against a rotating cam and an output arm that abuts a valve, which are supported on the same axis so as to be able to swing, and the input arm and the output arm are connected to each other so as not to swing relative to each other. In a variable valve mechanism that includes a switching mechanism that switches between a connected state and a non-connected state that releases the connection, and changes an opening / closing amount of the valve by the switching,
The output arm is configured to be displaceable between an adjacent position adjacent to the input arm and a separated position spaced apart from the input arm in the axial direction.
The switching mechanism is configured to connect the input arm and the output arm so as not to be relatively swingable when the output arm is displaced to the adjacent position when the output arm is displaced to the adjacent position. A connecting portion for releasing the connection when the output arm is displaced to the separated position,
The input arm includes an input roller that rotatably contacts the rotating cam at a contact portion with the rotating cam.
The connecting portion includes a connecting projection in which an end portion of a roller shaft that pivotally supports the input roller protrudes from the side surface of the input arm toward the output arm, and the output arm provided on the output arm. A variable valve mechanism comprising: a connecting hole into which the connecting protrusion is inserted when displaced to an adjacent position and from which the connecting protrusion is removed when displaced to the separated position .

Images