JP2010096102A - Variable valve train - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To displace each cam surface without providing a drive mechanism for each rotating member. <P>SOLUTION: This variable valve train 9 changes a valve drive state between a state in which the rotating members 20 drive valves 8, 8 by the cam surface 23 for driving of the rotating members and a state in which the rotating members 20 do not drive the valves 8, 8 by the cam surfaces 23 for driving by displacing a camshaft 10 in the longitudinal direction thereof by a drive mechanism 30 and relatively displacing the rotating members 20, 20, 20 in the displacement direction of the camshaft 10 relative to the camshaft 10 by displacement amount amplifying mechanisms 40, 40, 40. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a variable valve mechanism that changes a driving state of a valve in accordance with an operation state of an internal combustion engine.

  Among the variable valve mechanisms, like the variable valve mechanism 80 of Conventional Example 1 (Patent Document 1) shown in FIG. 7, the cam profile is arranged in the longitudinal direction on the camshaft 10 and goes in the same direction. A plurality of continuously changing taper-shaped continuous cam surfaces 83, 83, 83 are projected, and as shown in FIGS. 7A and 7B, the camshaft 81 is displaced in the length direction thereof, Some change the lift amount of the valves 8, 8... Driven by the continuous cam surfaces 83, 83, 83.

In addition, like the variable valve mechanism 90 of Conventional Example 2 (Non-Patent Document 1) shown in FIG. 8, the camshaft 91 includes a plurality of rotating members 92 and 92 that rotate together with the camshaft 91. , 92 are extrapolated, and one type of driving cam surface 93, 93,... Is formed on the outer peripheral surface of each rotating member 92, 92, 92. As shown in FIG. 8 (b), the rotary members 92, 92, 92 are moved by the drive cam surfaces 93, 93,. .. Between the execution state in which the drive cam surfaces 93, 93... Are not driven and the valves 8, 8... Are not driven as shown in FIG. · · · Some change the driving state.
Japanese Patent Laid-Open No. 10-18823 "Motor Fan Illustrated Vol.5" Calsonic Kansei Corporation, 2007, p. 51

  However, in the case of the conventional example 1, when switching the driving state of the valves 8, 8,..., The entire camshaft 81 having a relatively large mass is disposed in the length direction thereof, and the continuous cam surfaces 83, 83, 83 are arranged. Since the length to be displaced is also displaced, the efficiency is poor.

  Further, in the case of the conventional example 2, when the driving state of the valves 8, 8,... Is switched, only the rotating members 92, 92, 92 having a relatively small mass are displaced in the length direction of the camshaft 91. In this respect, it is more efficient than the first conventional example, but a drive mechanism 94, 94, 94 (two solenoids for each rotating member 92) is not provided for each rotating member 92, 92, 92. Not efficient in that respect

  Therefore, without providing a driving mechanism for each rotating member, each cam surface is simply moved by moving the entire cam shaft in the length direction by a length less than the length for which each cam surface is to be displaced. It is an object of the present invention to be able to be displaced by the length to be displaced.

  In order to achieve the above object, a variable valve mechanism according to the present invention includes a camshaft that rotates in a circumferential direction in accordance with the rotation of a crankshaft and is displaceable in a lengthwise direction, At least one type of driving valve that is arranged in the longitudinal direction and can be displaced relatively in the longitudinal direction and not in the circumferential direction of the camshaft, and rotates on the outer circumferential surface together with the camshaft. A plurality of rotating members each having a driving cam surface, a driving mechanism for displacing the camshaft in the longitudinal direction of the camshaft, and each rotating member, the camshaft being the length of the camshaft. When the camshaft is displaced in the vertical direction, the rotational force of the camshaft is changed to a displacement force in the displacement direction of the camshaft and transmitted to each rotary member, and each rotary member is transferred to the camshaft. A plurality of displacement amount amplifying mechanisms for relative displacement in the displacement direction of the shaft, and the camshaft is displaced in the lengthwise direction of the camshaft by the drive mechanism, and each rotating member is moved to the camshaft. A state in which each rotating member drives the valve with the one type of driving cam surface and the valve is not driven with the one type of driving cam surface by relative displacement in the displacement direction of the camshaft by the displacement amount amplification mechanism. The valve drive state is changed between states.

Although the said rotation member is not specifically limited, The case of following [1]-[3] is mentioned as an example.
[1] The rotating member does not include a cam surface other than the one type of driving cam surface, and when the valve is not driven by the one type of driving cam surface, the rotating member directly contacts the valve. No contact with the rocker arm or other intervening member.
[2] The rotating member includes a one-type cam cam surface that does not drive a valve on a length direction side of the cam shaft of the one type driving cam surface. When the valve is not driven, the one type of cam surface for resting directly contacts the valve or indirectly through an intervening member such as a rocker arm.
[3] The rotating member includes another type of driving cam surface on the longitudinal direction side of the cam shaft of the one type of driving cam surface, and does not drive the valve with the one type of driving cam surface. When the valve is driven with the other type of driving cam surface in the state.

In the case of the above [2] and [3], there are no particular limitations on the two types of cam surfaces: the one type of driving cam surface and the one type of resting cam surface or the other type of driving cam surface. The following cases [i] and [ii] are given as examples.
[I] The two cam surfaces have intermittent cam profile changes at the boundary between them.
[Ii] The rotating member includes a tapered continuous cam surface whose cam profile continuously changes as the cam shaft advances in the length direction of the camshaft on the outer peripheral surface, and the entire peripheral portion of any one of the continuous cam surfaces is One of the two types of cam surfaces, and one of the other circumferential portions different from the circumferential portion is the other of the two types of cam surfaces.

  Although the displacement amount amplifying mechanism is not particularly limited, the displacement amount amplifying mechanism is provided on the outer peripheral surface of the rotating member, extends in the circumferential direction of the outer peripheral surface, and shifts to one of the length directions of the cam shaft as it goes in the rotating direction of the cam shaft. One guide groove and the one guide groove which is provided on the outer peripheral surface of the rotating member and extends in the circumferential direction of the outer peripheral surface and shifts to the other in the longitudinal direction of the cam shaft as it goes in the rotational direction of the cam shaft. Is provided in the cylinder head that supports the camshaft, and when the camshaft is displaced in one length direction of the camshaft, it engages with the one guide groove. When the rotating member is displaced in one length direction of the cam shaft according to the rotation of the cam shaft, and the cam shaft is displaced in the other length direction of the cam shaft, the other guide groove It is preferable that the rotating member engaging is configured including an engagement pin to be displaced in the longitudinal direction other of the cam shaft in accordance with rotation of the cam shaft.

  Here, the engagement pin is not particularly limited. When the engagement pin is engaged with the one guide groove, the engagement pin is engaged with the one guide groove and the other guide groove. Prevents the engagement pin from moving to the other guide groove at the intersection, and when the engagement pin is engaged with the other guide groove, the engagement pin is moved to the one guide groove at the intersection. It is preferable to provide an escape prevention portion that prevents the escape.

  The escape prevention part is not particularly limited, but may be a protrusion that extends from the engagement part in the circumferential direction of the camshaft, or the engagement part itself is formed in a shape that extends in the circumferential direction of the camshaft. The case where it becomes is mentioned as an example.

  According to the present invention, since there is a displacement amount amplifying mechanism, each drive cam is simply displaced in the length direction by a length less than the length of each drive cam surface to be displaced. The surface can be displaced by the length to be displaced. In addition, since it is only necessary to displace the camshaft by the drive mechanism, it is not necessary to provide a drive mechanism for each rotating member.

  The variable valve mechanism 9 of the present invention rotates in the circumferential direction according to the rotation of a crankshaft (not shown), and is arranged in the longitudinal direction on the camshaft 10 that is provided so as to be displaceable in the lengthwise direction. At least one for driving the valves 8, 8,..., Which can be relatively displaced in the same direction, can be relatively displaced in the circumferential direction of the camshaft 10, and can rotate with the camshaft 10 on the outer peripheral surface. A plurality of rotating members 20, 20, 20 each having a type of driving cam surface 23, 23, 23, a drive mechanism 30 for displacing the camshaft 10 in its length direction, and each rotating member 20, 20, 20 When the camshaft 10 is displaced in the length direction, the rotational force of the camshaft 10 is changed to a displacement force in the displacement direction of the camshaft 10 and transmitted to the rotary members 20, 20, 20. Te, and each rotary member 20, 20, 20 is constructed and a plurality of displacement amplification mechanism 40,40,40 for relative displacement in the displacement direction of the camshaft 10 relative to the cam shaft 10.

  Then, the camshaft 10 is displaced in the longitudinal direction of the camshaft 10 by the drive mechanism 30, and the rotating members 20, 20, 20 are moved to the camshaft 10 by the displacement amount amplifying mechanisms 40, 40, 40. By rotating the camshaft 10 relative to each other in the displacement direction, the rotary members 20, 20, 20 drive the valves 8, 8,... With the one kind of driving cam surfaces 23, 23, 23 and the one kind. The drive state of the valves 8, 8,... Is changed between the state in which the valves 8, 8,.

  Here, the displacement amount amplifying mechanism 40 is provided on the outer peripheral surface of the rotating member 20 and extends in the circumferential direction of the outer peripheral surface, and shifts to one of the length directions of the camshaft 10 as the camshaft 10 rotates. The guide groove 41 is provided on the outer peripheral surface of the rotating member 20, extends in the circumferential direction of the outer peripheral surface, and shifts to the other in the longitudinal direction of the camshaft 10 as the camshaft 10 rotates. 41 is provided in the cylinder head 6 that supports the camshaft 10 and the other guide groove 42 that intersects with the crossing portion X. When the camshaft 10 is displaced in one of its length directions, the guide groove 41 is engaged. Then, the rotating member 20 is displaced in one longitudinal direction of the camshaft 10 in accordance with the rotation of the camshaft 10, and when the camshaft 10 is displaced in the other longitudinal direction, it engages with the other guide groove 42. The rotary member 20 is configured and a engaging pin 43 to be displaced in the longitudinal direction other of the cam shaft 10 in accordance with rotation of the cam shaft 10.

  When the engaging pin 43 is engaged with one guide groove 41 in an engaging portion that engages with one guide groove 41 and the other guide groove 42 of the pin, Preventing the other guide groove 42 from escaping at the intersection X and preventing the engagement pin 43 from escaping to the one guide groove 41 at the intersection X when engaged with the other guide groove 42. The escape prevention part 43a is provided.

  The variable valve mechanism 9 of this embodiment shown in FIGS. 1 to 5 is provided for three pairs of intake or exhaust valves 8, 8,... Provided in pairs for each of the three cylinders. The drive state of each valve 8, 8,... Is changed between the execution state and the rest state. The variable valve mechanism 9 includes the following one camshaft 10, three rotating members 20, 20, 20, one drive mechanism 30, three displacement amount amplifying mechanisms 40, 40, 40, Three rocker arms 50, 50, 50 and three pairs of valve springs 60, 60,. In the following, for convenience, one of the length directions of the camshaft 10 is set to the right and the other is set to the left. However, the right and the left may be opposite.

[Camshaft 10]
The camshaft 10 is a shaft extending in the left-right direction. The camshaft 10 is inserted into a plurality of standing wall portions 7, 7... 10 is supported so as to be displaceable in the circumferential direction. The camshaft 10 has a base end portion 11 connected to a crankshaft (not shown), and rotates in the circumferential direction of the camshaft 10 according to the rotation of the crankshaft (not shown). Mounting portions 12, 12, and 12 for mounting the rotating members 20, 20, and 20 are provided at three positions on the outer peripheral surface of the camshaft 10 that are adjacent to the three cylinders in the left-right direction. Then, on the left side of each mounting portion 12, when the camshaft 10 is displaced in the right direction, the right driving protrusion 13 that contacts the rotating member 20 from the left side and presses and rotates the rotating member 20 in the right direction. To the right of each mounting portion 12, when the camshaft 10 is displaced in the left direction, it comes into contact with the rotating member 20 from the right side and drives the left side by pressing the rotating member 20 in the left direction. A protrusion 14 is provided.

[Rotating members 20, 20, 20]
Each rotating member 20 is a cylindrical member that is extrapolated to the camshaft 10, and the attached portion 22 provided on the inner peripheral surface thereof can be relatively displaced in the left-right direction with respect to the attaching portion 12 of the camshaft 10. The camshaft 10 is engaged in the circumferential direction so as not to be relatively displaced. The rotating member 20 includes a driving cam surface 23 for driving the valves 8, 8... That rotate with the camshaft 10 at the right portion of the outer peripheral surface. The cam surface 24 for the pause which does not drive 8 and 8 is provided. More specifically, the drive cam surface 23 has a cam nose 23a that has a basic circular cross section and protrudes from the true circle. On the other hand, the resting cam surface 24 has a true circular cross section and is not provided with a cam nose. Each of these three rotating members 20, 20, and 20 is installed at an angle of 120 degrees with respect to each other.

[Drive mechanism 30]
The drive mechanism 30 is a mechanism for displacing the camshaft 10 in the left-right direction, and includes a right drive unit 31 that drives the camshaft 10 in the right direction and a left drive unit 36 that drives in the left direction.

  The right drive unit 31 includes a right drive groove 32, a right drive pin 33, and a right drive solenoid 34. The right drive groove 32 is recessed on the outer peripheral surface of the right drive enlarged diameter portion 15 protruding from the camshaft 10 and extends in the circumferential direction of the camshaft 10. It is displaced in the direction. Specifically, the right drive groove 32 has a start end portion 32a positioned at an end portion on the rotation direction side of the camshaft 10 and extends straight in a direction opposite to the rotation direction of the camshaft 10 without shifting from the start end to the left and right. The intermediate direction portion 32b extends in the direction opposite to the rotation direction of the camshaft 10 from the end of the start end portion 32a, and shifts to the left side (right direction toward the rotation direction) toward the opposite direction of the rotation direction, thereby terminating the end portion 32c. However, it extends straight in the opposite direction of the rotation direction of the camshaft 10 without shifting from the end of the lengthwise intermediate portion 32b to the left and right, and gradually becomes shallower toward the opposite direction of the rotation direction. The right drive pin 33 is a pin extending in the rearward direction. The right drive solenoid 34 supports the rear part of the right drive pin 33 so that the rear part of the right drive pin 33 can be driven in the front-rear direction of the pin, and drives the right drive pin 33 forward to drive the tip part of the right drive pin 33 to the right. Engage with the groove 32.

  The left drive unit 36 includes a left drive groove 37, a left drive pin 38, and a left drive solenoid 39. The left drive groove 37 is recessed in the outer peripheral surface of the left drive enlarged diameter portion 16 projecting from the camshaft 10, extends in the circumferential direction of the camshaft 10, and moves toward the left in the rotational direction of the camshaft 10. It is displaced in the direction. Specifically, the left drive groove 37 has a start end portion 37a positioned at an end portion on the rotation direction side of the camshaft 10 that extends straight in a direction opposite to the rotation direction of the camshaft 10 without shifting from the start end to the left and right. The intermediate direction portion 37b extends from the end of the start end portion 37a in the direction opposite to the rotation direction of the camshaft 10, and shifts in the right direction (left direction toward the rotation direction) as it goes in the opposite direction of the rotation direction. However, it extends straight in the direction opposite to the rotation direction of the camshaft 10 without shifting left and right from the end of the lengthwise intermediate portion 37b, and gradually becomes shallower toward the direction opposite to the rotation direction. The left drive pin 38 is a pin extending in the rear-rear direction. The left drive solenoid 39 supports the rear part of the left drive pin 38 so that the rear part of the left drive pin 38 can be driven in the front-rear direction of the pin, and drives the left drive pin 38 forward to drive the front end part of the left drive pin 38 to the left. Engage with the groove 37.

[Displacement amplification mechanism 40, 40, 40]
When the camshaft 10 is displaced in the right direction, each displacement amount amplifying mechanism 40 changes the rotational force of the camshaft 10 to the displacement force in the rightward direction and transmits it to the rotating member 20 to the camshaft 10. When the rotary member 20 is relatively displaced in the right direction and the camshaft 10 is displaced in the left direction, the rotational force of the camshaft 10 is changed to the leftward displacement force and transmitted to the rotary member 20, and the camshaft 10 is transmitted to the camshaft 10. On the other hand, it is a mechanism that relatively displaces the rotating member 20 in the left direction. The displacement amount amplifying mechanism 40 includes a right guide groove 41 and a left guide groove 42, an engagement pin 43, and a displacement spring 48 described below.

  The right guide groove 41 is provided at the left portion of the outer peripheral surface of the rotating member 20, extends in the circumferential direction of the outer peripheral surface, and is shifted to the right as the camshaft 10 rotates. The left guide groove 42 is provided at the left portion of the outer peripheral surface of the rotating member 20 and extends in the circumferential direction of the outer peripheral surface. The left guide groove 42 is shifted to the left as the camshaft 10 rotates and is guided to the right at the intersection X. Crosses the groove 41. Specifically, the start end portions 41a and 42a positioned at the end portions of the right guide groove 41 and the left guide groove 42 on the rotation direction side of the camshaft 10 have the start end portion 41a of the right guide groove 41 on the right side, and the left guide groove 42. The starting end portions 42a are arranged on the left side, and extend straight from the starting ends in the opposite direction to the rotational direction of the camshaft 10 without being shifted to the left or right. Further, the length direction intermediate portions 41b and 42b of the right guide groove 41 and the left guide groove 42 respectively extend in the opposite direction to the rotation direction of the camshaft 10 from the end of the respective start end portions 41a and 42b, and are opposite to the rotation direction. The length direction intermediate portion 41b of the right guide groove 41 is in the left direction (right direction as it goes in the rotation direction), and the length direction intermediate portion 42b of the left guide groove 42 is in the right direction (as it goes in the rotation direction). Are crossing at the intersection X. Further, the end portions 41c and 42c of the right guide groove 41 and the left guide groove 42 are left at the end portions 41c of the right guide groove 41 as they are from the end of the lengthwise intermediate portions 41b and 42b. The end portions 42c of the camshaft 10 are arranged so as to be on the right side, extend straight in the direction opposite to the rotation direction of the camshaft 10 without being shifted to the left and right, and gradually become shallower toward the direction opposite to the rotation direction. Here, the length direction intermediate portions 41 b and 42 b of the right guide groove 41 and the left guide groove 42 are positions where the cam nose 23 a on the outer peripheral surface of the rotating member 20 engages with the engagement pin 43 when the valves 8 and 8 are not driven. Is provided.

  The engagement pin 43 is a pin extending in the forward and rearward direction, and the rear portion of the engagement pin 43 is inserted inside a bottomed cylindrical body 44 fixed to the cylinder head 6 that supports the camshaft 10. Thus, the engagement pin 43 is supported by the body 44 so as to be displaceable in the front-rear direction. A spring 45 that presses the engagement pin 43 forward is interposed between the bottom surface of the body 44 and the rear end surface of the engagement pin 43 so that the engagement pin 43 is compressed. The front end surface is pressed against the left part of the outer peripheral surface of the rotating member 20. Further, the engaging pin 43 includes a deflection preventing portion 43a having a tip portion formed in a shape extending in the circumferential direction of the camshaft 10 (a shape such as an oval shape in a cross-sectional view). When the tip of the engagement pin 43 is engaged with the right guide groove 41, the tip of the engagement pin 43 is prevented from being displaced to the left guide groove 42 at the intersection X, When the distal end portion of 43 is engaged with the left guide groove 42, the distal end portion of the engagement pin 43 is prevented from being displaced to the right guide groove 41 at the intersection X.

  The displacement spring 48 presses the rotating member 20 to the right when the rotating member 20 is to the right of the left-right stroke with respect to the camshaft 10, and presses the rotating member 20 to the left when it is to the left. Specifically, the displacement spring 48 is a torsion coil spring that extends in the left-right direction and has a middle portion in the length direction wound in a coil shape, and is between the inner peripheral surface of the rotating member 20 and the outer peripheral surface of the camshaft 10. Is intervened. The left and right ends of the displacement spring 48 engage with the inner peripheral surface of the rotating member 20 so as not to be relatively displaceable in the left-right direction, and the intermediate portion in the length direction is a front surface provided on the outer peripheral surface of the camshaft 10. It is in contact with a curved surface 49 that is curved in a convex shape as viewed.

[Rocker arms 50, 50, 50]
Each rocker arm 50 is a two-valve integrated arm that drives a pair of valves 8 and 8 at the same time, extends parallel to the diameter of the camshaft 10, and is supported by a lash adjuster 59 so as to be swingable. A roller 51 that selectively contacts the driving cam surface 23 and the resting cam surface 24 of the rotating member 20 is provided in the middle in the length direction, and the tip end portion is divided into left and right to contact the pair of valves 8 and 8. ing.

[Valve spring 60, 60 ...]
Each valve spring 60 is a return spring for biasing the valve 8 in the closing direction.

  Next, using the variable valve mechanism 9 of the present embodiment, the state of switching the driving state of the valves 8 and 8 between the execution state and the pause state is switched from the {1} execution state to the pause state. In the following, the explanation will be divided into the case of {2} and switching from the sleep state to the execution state.

{1} When switching from the running state to the resting state In the running state, as shown in FIG. 3A, the camshaft 10 and the rotating member 20 are respectively arranged on the left side of their strokes. The driving cam surface 23 is in contact with the roller 51 of the rocker arm 50. At this time, the right drive pin 33 and the left drive pin 38 are arranged on the rear side of the front-rear direction stroke. From this state, the right drive pin 33 is driven forward by the right drive solenoid 34, and the front end surface of the right drive pin 33 comes into contact with the outer peripheral surface of the right drive enlarged diameter portion 15 of the camshaft 10. From this state, when the camshaft 10 rotates and the start end portion 32a of the right drive groove 32 comes to the front of the tip end portion of the right drive pin 33, as shown in FIG. The portion is pushed into the start end portion 32 a of the right drive groove 32, and the right drive pin 33 engages with the right drive groove 32. From this state, as the camshaft 10 further rotates, the right inner surface of the lengthwise intermediate portion 32b of the right drive groove 32 is pressed against the right outer surface of the tip portion of the right drive pin 33, as shown in FIG. As shown in c), the camshaft 10 is displaced in the right direction, and then the tip end portion of the right drive pin 33 is pushed out from the end portion 32c of the right drive groove 32.

  As the camshaft 10 is displaced in the right direction, as shown in FIG. 3C, the rotating member 20 is also pressed rightward by the right driving projection 13 and displaced in the right direction. The starting end portion 41a of 41 is displaced to a position overlapping the circumferential direction side of the camshaft 10 of the engaging pin 43. From this state, when the camshaft 10 rotates and the start end portion 41 a of the right guide groove 41 comes to the tip of the engagement pin 43, the distal end portion of the engagement pin 43 is moved to the right by the restoring force of the spring 45. As shown in FIG. 3C, the engagement pin 43 is engaged with the right guide groove 41 by being pushed into the start end portion 41a of the guide groove 41. From this state, as the camshaft 10 further rotates, the right inner surface of the middle portion 41b in the longitudinal direction of the right guide groove 41 is located at the right of the distal end portion of the engagement pin 43 as shown in FIG. The rotating member 20 is displaced rightward relative to the camshaft 10 by being pressed by the outer surface, and then the tip end portion of the engagement pin 43 is pushed out from the end portion 41 c of the right guide groove 41.

  Then, from this state, as shown in FIG. 3D, the displacement spring 48 presses the right part of the curved surface 49 provided on the outer peripheral surface of the camshaft 10 to the left. Due to the reaction, as shown in FIG. 3E, the rotating member 20 is further displaced relative to the camshaft 10 in the right direction, and the right side surface of the rotating member 20 comes into contact with the left side surface of the left driving projection 14. This stops the relative displacement. As a result, the right guide groove 41 and the left guide groove 42 are displaced to the right of the engagement pin 43 that cannot be engaged with the engagement pin 43.

  As a result of the series of operations described above, as shown in FIG. 4A, the one rotating member 20 is stopped from the execution position on the left side of the stroke in which the rotating cam 20 comes into contact with the roller 51 of the rocker arm 50 at the driving cam surface 23. The cam surface 24 is displaced to the rest position on the right side of the stroke contacting the roller 51 of the rocker arm 50, whereby the driving state of the pair of valves 8 and 8 corresponding to the one rotating member 20 is changed from the execution state to the rest state. Switch to. As shown in FIG. 4B, another rotating member 20 is similarly displaced in the right direction corresponding to the other rotating member 20, as shown in FIG. The driving state of the pair of valves 8 and 8 is also switched from the execution state to the resting state. Further, as shown in FIG. 4C, the remaining rotating member 20 is also displaced in the right direction in response to the displacement of the other rotating member 20, and corresponds to the remaining rotating member 20. The driving state of the valves 8 and 8 is also switched from the running state to the resting state.

{2} When switching from the resting state to the running state At this time, in the case of {1} above, the right is to the left and the left to the right, the driving cam surface is driven to the resting cam surface, and the resting cam surface is driven. In the cam surface, the execution state is changed to the dormant state and the dormant state is changed to the execution state, and the numbers of the respective members are replaced with the numbers corresponding to the member names after the replacement, and descriptions relating to the drawings It is the same with deleting.

  According to the present embodiment, since there are the displacement amount amplifying mechanisms 40, 40, 40, the camshaft 10 is moved in the left-right direction, and the driving cam surfaces 23, 23, 23 and the pausing cam surfaces 24, 24, 24 are arranged. As shown in FIGS. 5 (a) and 5 (b), the drive cam surfaces 23, 23, 23 and the pause cam surfaces 24, 24, 24 can be displaced by the length to be displaced.

  Further, since it is only necessary to displace one camshaft 10 in the left-right direction by one drive mechanism 30, it is not necessary to provide a drive mechanism for each of the rotating members 20, 20, and 20, thereby providing a variable valve mechanism. 9 is simplified and made compact. In addition, if there is a driving mechanism for each of the rotating members 20, 20, 20, there is a risk that the engine will malfunction due to a shift in the steps due to signal disturbance between the driving mechanisms, but in this embodiment, There is no such worry.

  Further, since the right guide groove 41 and the left guide groove 42 are provided so as to intersect with each other at the intersection X, it is only necessary to provide one engagement pin 43 for these two grooves, thereby In addition, the variable valve mechanism 9 is simplified and made compact. Further, since the engagement pin 43 includes the deflection preventing portion 43a, there is no fear that the engagement pin 43 is displaced from one of the right guide groove 41 and the left guide groove 42 at the intersection X. .

  The present invention is not limited to the configuration of the above embodiment, and can be modified and embodied without departing from the spirit of the invention. For example, the following modifications 1 to 4 can be made. May be.

[Modification 1]
In the embodiment, a case is shown in which there are three pairs of the valves 8 and 8 and the valve springs 60 and 60, and three rotation members 20, three displacement amount amplifying mechanisms 40 and three rocker arms 50, but the number thereof is particularly limited. For example, it may not be 3 pairs or 3 each, but may be 4 pairs, 4 pairs, 5 pairs, 5 pairs, 6 pairs, 6 pairs, or the like.

[Modification 2]
In the embodiment, the case where the rocker arm 50 is a two-valve integrated arm that drives the pair of valves 8 and 8 at the same time is shown. However, as shown in FIG. In place of the pair of rocker arms 50, 50 that drive only eight, each rotary member 20 has a pair of drive cam surfaces 23, 23 and a pair of pause cam surfaces 24, 24 that abut against the pair of rocker arms 50, 50. May be provided.

[Modification 3]
1 to 5 of the embodiment show the case where the rotation direction of the camshaft 10 is clockwise when viewed from the left side, but the counterclockwise direction is when the driving of the valves 8, 8,. May be counterclockwise as shown in FIG. In this case, the shapes of the right drive groove 32, the left drive groove 37, the right guide groove 41, and the left guide groove 42 are also opposite to the shapes shown in FIGS. 1 to 5 in the circumferential direction of the camshaft 10, respectively. .

[Modification 4]
1 to 5 of the embodiment show a case where one right driving groove 32 is provided in the right driving enlarged diameter portion 15 and one left driving groove 37 is provided in the left driving enlarged diameter portion 16. 6 (c), a plurality of right drive grooves 32, 32,... Are arranged side by side in the circumferential direction of the camshaft 10 in the right drive enlarged diameter portion 15, and the left drive enlarged diameter portion 16 is arranged. A plurality of left drive grooves 37, 37... May be arranged side by side in the circumferential direction of the camshaft 10. The larger the number of grooves, the more complicated the structure of the camshaft 10, while the larger the number, the more the camshaft 10 is driven in the left-right direction at an earlier timing, and the valves 8, 8,.・ The driving state can be switched.

The top view which shows the variable valve mechanism of the Example of this invention is shown to (a), The left side sectional drawing in each part is shown to (b) (c) (d). It is the figure which shows the partial enlarged plan view of the variable valve mechanism of the Example in (a), and shows the partial expanded plane sectional view in (b). It is the partial enlarged plan view which shows the mode at the time of switching the drive state of a valve | bulb from an execution state to a dormant state with the variable valve mechanism of the Example in order (a)-(e). It is a top view which shows a mode at the time of switching the drive state of a valve | bulb from a drive state to a rest state with the variable valve mechanism of the Example in order to (a)-(c). In the variable valve mechanism of the same Example, it is a top view which shows the mode at the time of making the drive state of a valve into a dormant state, and shows the mode at the time of making it into an execution state. A partial enlarged plan view of the variable valve mechanism of Modification 2 is shown in FIG. 5A, a left side sectional view of the variable valve mechanism of Modification 3 is shown in FIG. It is a figure which shows an enlarged plan view in (c). It is the top view which shows the mode at the time of decreasing the lift amount of a valve | bulb with the variable valve mechanism of the prior art example 1, and shows the mode at the time of increasing (b). In the variable valve mechanism of the prior art example 2, it is a top view which shows the mode at the time of making the drive state of a valve into a dormant state, and shows the mode at the time of making it into an execution state.

Explanation of symbols

6 Cylinder Head 8 Valve 9 Variable Valve Mechanism 10 Camshaft 20 Rotating Member 23 Drive Cam Surface 30 Drive Mechanism 40 Displacement Amplification Mechanism 41 Right Guide Groove 42 Left Guide Groove 43 Engagement Pin 43a Escape Prevention Part X Intersection

Claims (3)

A camshaft (10) that rotates in the circumferential direction in accordance with the rotation of the crankshaft and is displaceable in the length direction;
The camshaft is arranged in the lengthwise direction of the camshaft and is extrapolated so as to be relatively displaceable in the lengthwise direction and not to be relatively displaceable in the circumferential direction of the camshaft, and rotates on the outer peripheral surface together with the camshaft. A plurality of rotating members (20) each having at least one type of drive cam surface (23) for driving the valve (8) according to
A drive mechanism (30) for displacing the camshaft in the longitudinal direction of the camshaft;
Provided for each rotating member, when the camshaft is displaced in the length direction of the camshaft, the rotational force of the camshaft is changed to a displacement force in the displacement direction of the camshaft and transmitted to each rotating member, A plurality of displacement amount amplifying mechanisms (40) configured to relatively displace each rotating member in the displacement direction of the camshaft with respect to the camshaft;
The camshaft (10) is displaced in the length direction of the camshaft by the drive mechanism (30), and each rotating member (20) is moved by the displacement amount amplifying mechanism (40) with respect to the camshaft. By relative displacement in the displacement direction, each rotary member (20) drives the valve (8) with the one type of drive cam surface (23) and drives the valve with the one type of drive cam surface. A variable valve mechanism that changes the driving state of the valve between the non-operating state and the non-operating state. The displacement amount amplification mechanism (40)
One guide groove (41) provided on the outer peripheral surface of the rotating member and extending in the circumferential direction of the outer peripheral surface and deviating in one of the length directions of the camshaft as it goes in the rotational direction of the camshaft;
Provided on the outer peripheral surface of the rotating member, extends in the circumferential direction of the outer peripheral surface, and shifts to the other in the length direction of the camshaft toward the rotating direction of the camshaft and intersects with the one guide groove (X) The other guide groove (42) intersecting at
Provided in the cylinder head (6) supporting the camshaft, when the camshaft is displaced in one of the camshaft lengthwise directions, the camshaft engages with the one guide groove to rotate the rotating member of the camshaft. When the camshaft is displaced to one side in the longitudinal direction of the camshaft, and the camshaft is displaced to the other in the longitudinal direction of the camshaft, the camshaft is engaged with the other guide groove and the rotating member is moved according to the rotation of the camshaft. The variable valve mechanism according to claim 1, further comprising an engagement pin (43) that is displaced in the other longitudinal direction of the camshaft.   When the engaging pin (43) engages with the one guide groove, the engaging pin engages with the one guide groove and the other guide groove of the engagement pin. Prevents the pin from escaping to the other guide groove at the intersection, and prevents the engagement pin from escaping to the one guide groove at the intersection when engaged with the other guide groove. The variable valve mechanism according to claim 2, further comprising an escape preventing portion (43 a).

Images