JP7004152B2 - Valve mechanism - Google Patents

Description

The present invention relates to a valve train of an internal combustion engine.

The valve operation mechanism of the internal combustion engine described in Patent Document 1 includes a camshaft, a cam connected to the camshaft, and a rocker arm pressed by the cam. One end of the rocker arm is supported by a lash adjuster and the other end is supported by an engine valve. When the rocker arm is pressed by the cam, the other end is swung around the one end.

The rocker arm includes an inner arm having a roller pressed by a cam and an outer arm mounted on the inner arm. One end of the inner arm is in contact with the lash adjuster, and the other end of the outer arm is in contact with the engine valve. The inner arm is provided so as to be tiltable with respect to the outer arm centering on one end. When the connecting pin is locked between the inner arm and the outer arm, the relative tilting of the inner arm and the outer arm is restricted, resulting in a locked state. In this state, when the inner arm is pressed by the cam, the outer arm swings together with the inner arm to drive the engine valve. On the other hand, when the connecting pin is not locked to the inner arm and the outer arm, the unlocked state allows the relative tilt of the inner arm and the outer arm. In this state, when the inner arm is pressed by the cam, the inner arm tilts with respect to the outer arm. Therefore, the outer arm does not swing and the engine valve is not driven.

The rocker arm described in Patent Document 1 is provided with a switching mechanism. The switching mechanism has a connecting pin, a rod to which one end of the connecting pin is connected, and an electric actuator for moving the rod. In this switching mechanism, the position of the connecting pin is changed through the rod by driving the actuator. When the connecting pin is placed between the inner arm and the outer arm and locked to them, the rocker arm is locked, and the connecting pin moves from the position between the inner arm and the outer arm to engage these. When the stop is released, the rocker arm is unlocked.

Japanese Unexamined Patent Publication No. 9-21306

In the valve operating mechanism described in Patent Document 1, one switching mechanism is provided for one rocker arm. Therefore, it is necessary to arrange as many actuators as there are rocker arms.

The valve operating mechanism for solving the above problems includes a camshaft, a cam connected to the camshaft, one end being supported by a rush adjuster and the other end being supported by an engine valve and pressed by the cam. This is a valve mechanism including a plurality of rocker arms that swing the other end portion around the one end portion, and the rocker arm is provided so as to be relatively tiltable with the inner arm and the inner arm. Switch between the locked outer arm and the locked state in which the relative tilt of the inner arm and the outer arm is restricted, and the unlocked state in which the relative tilt of the inner arm and the outer arm is allowed. It has a possible switching mechanism, the switching mechanism is connected to an operation shaft extending in the same direction as the axial direction of the camshaft, and is arranged side by side at a position corresponding to the rocker arm. It has a swing plate, an actuator for rotating the operation shaft, and connecting pins arranged side by side at positions corresponding to the swing plate, and the actuator rotates the operation shaft to rotate the swing plate. And the connecting pin are brought into contact with each other, and the position of the connecting pin is switched between the first position in which the state of the inner arm and the outer arm is in the locked state and the second position in which the state of the outer arm is in the unlocked state.

In the above configuration, a plurality of connecting pins can be operated by driving the actuator of the switching mechanism to displace the swing plate connected to the operation shaft. This makes it possible to switch the states of a plurality of rocker arms with one actuator. Therefore, the number of actuators can be reduced as compared with the configuration in which the state of one rocker arm is switched by one actuator.

Further, in the valve operation mechanism, the operation shaft has a first shaft with which the actuator abuts and a second shaft arranged coaxially with the first shaft and having an insertion hole through which the first shaft is inserted. An elastic member that is connected to the first shaft and the second shaft with the first shaft inserted through the second shaft and allows relative rotation between the first shaft and the second shaft. It is desirable that the swing plate includes a first swing plate connected to the first shaft and a second swing plate connected to the second shaft.

In the above configuration, the first shaft and the second shaft are connected by an elastic member so as to be relatively rotatable. A first swing plate is connected to the first shaft, and a second swing plate is connected to the second shaft. Therefore, in the process of rotating the operation shaft, it is possible to make the timing at which the first swing plate abuts on the connecting pin different from the timing at which the second swing plate abuts on the connecting pin. Therefore, according to the above configuration, it is possible to switch the states of the plurality of rocker arms at different timings instead of switching them all at the same timing.

Further, in the valve operation mechanism, the operation shaft has a plurality of split shafts having the same number of cylinders as the number of cylinders of the internal combustion engine, and an elastic member for connecting the split shafts to each other, and the split shafts are coaxial with each other. A central shaft that is arranged and is arranged on the innermost side of the plurality of divided shafts and with which the actuator abuts, and an insertion hole through which the central shaft is inserted are provided on the outer peripheral side of the central shaft. In the elastic member, the inner peripheral side shaft arranged on the inner peripheral side of the divided shaft is arranged on the outer peripheral side of the inner peripheral side shaft. It is desirable that the swing plate is connected to each of the plurality of divided shafts so that the relative rotation between the inner peripheral side shaft and the outer peripheral side shaft is allowed in a state of being inserted through the outer peripheral side shaft.

In the above configuration, the split shafts are connected to each other so as to be relatively rotatable by an elastic member. A swing plate is connected to each of the split shafts. Therefore, in the process of rotating the operation shaft, it is possible to make the timing at which the swing plate comes into contact with the connecting pin different for each split shaft. Therefore, according to the above configuration, it is possible to switch the states of the plurality of rocker arms at different timings for each cylinder, instead of switching all the states at the same timing.

The cross-sectional view which shows typically the structure of the internal combustion engine which has the valve movement mechanism of 1st Embodiment. Side view of the camshaft. A perspective view of the rocker arm. Perspective view of the inner arm. Sectional view of the rocker arm. Perspective view of the outer arm. Sectional drawing which shows the structure of the operation shaft schematically. The graph which shows the relationship between the cam angle and the valve lift amount in a large cam and a small cam. Sectional drawing which shows typically the state when a rocker arm swings by a small cam. Sectional drawing which shows typically the state when a rocker arm swings by a large cam. The schematic diagram which shows the structure when the state of a rocker arm is an unlocked state. The schematic diagram which shows the structure when the state of a rocker arm is switched to the locked state by the 2nd swing plate. The schematic diagram which shows the structure when the state of a rocker arm is switched to the locked state by the 1st swing plate. A graph showing the relationship between the torque generated by the motor and the rotation angle. The cross-sectional view which shows typically the structure of the operation shaft in the valve movement mechanism of 2nd Embodiment. The schematic diagram which shows the structure when the state of a rocker arm is an unlocked state. A graph showing the relationship between the torque generated by the motor and the rotation angle. (A) and (b) are timing charts showing changes in the lift amount of the intake valve in each cylinder. The cross-sectional view which shows the structure of the modification of the intake side rocker arm schematically. The cross-sectional view which shows the state which the connecting pin was pulled out in the rocker arm on the intake side. The schematic diagram which shows the structure of the operation shaft in a valve operation mechanism. The cross-sectional view which shows the structure of the other modification of the intake side rocker arm schematically. The cross-sectional view which shows the structure of the other modification of the intake side rocker arm schematically.

(First Embodiment)
The first embodiment of the valve operating mechanism will be described with reference to FIGS. 1 to 14.
As shown in FIG. 1, four cylinders 20 (first cylinder # 1 to fourth cylinder # 4) are formed in the internal combustion engine 200 having a valve operating mechanism. The arrangement direction of the cylinders 20 (depth direction in FIG. 1) is referred to as a cylinder arrangement direction. FIG. 1 shows an example of the first cylinder # 1 arranged on one end side in the cylinder arrangement direction. The cylinder head 10 of the internal combustion engine 200 is formed with an intake port 11 and an exhaust port 12 communicating with the cylinder 20. A fuel injection valve 21 is arranged at the intake port 11. The fuel injection valve 21 injects fuel into the intake port 11. The cylinder head 10 is formed with a first accommodating portion 13 provided above the intake port 11 and a second accommodating portion 14 provided above the exhaust port 12. Each of the first accommodating portion 13 and the second accommodating portion 14 is formed in a recessed shape with respect to the upper end of the cylinder head 10. An intermediate portion 15 arranged between the first accommodating portion 13 and the second accommodating portion 14 is formed at the upper end portion of the cylinder head 10. The intermediate portion 15 is formed in a shape recessed with respect to the upper end of the cylinder head 10, and communicates the first accommodating portion 13 and the second accommodating portion 14. The depth of the intermediate portion 15 is shallower than the depth of each of the first accommodating portion 13 and the second accommodating portion 14. Therefore, at the upper end of the cylinder head 10, a holding portion 16 projecting above the bottom walls of the first accommodating portion 13 and the second accommodating portion 14 between the first accommodating portion 13 and the second accommodating portion 14. Is provided. The cylinder head 10 is formed with a first communication hole 17 that communicates the first accommodating portion 13 and the intake port 11. A first valve guide 22 formed in a cylindrical shape is fixed to the first communication hole 17. Further, the cylinder head 10 is formed with a second communication hole 18 for communicating the second accommodating portion 14 and the exhaust port 12. A second valve guide 23 formed in a cylindrical shape is fixed to the second communication hole 18.

The internal combustion engine 200 is provided with an intake valve 24 that communicates with and shuts off the intake port 11 and the cylinder 20. The intake valve 24 extends from the intake port 11 to the first accommodating portion 13 through the first valve guide 22. A first valve lifter 25 is connected to an upper end portion of the intake valve 24 arranged in the first accommodating portion 13. A first compression spring 26 is arranged between the first valve lifter 25 and the first accommodating portion 13. The first compression spring 26 urges the intake valve 24 from the intake port 11 toward the first accommodating portion 13. As a result, the intake valve 24 comes into contact with the cylinder head 10 as shown in FIG. 1 and shuts off between the intake port 11 and the cylinder 20.

Further, the internal combustion engine 200 is provided with an exhaust valve 27 that communicates with and shuts off the exhaust port 12 and the cylinder 20. The exhaust valve 27 extends from the exhaust port 12 to the second accommodating portion 14 through the second valve guide 23. A second valve lifter 28 is connected to an upper end portion of the exhaust valve 27 arranged in the second accommodating portion 14. A second compression spring 29 is arranged between the second valve lifter 28 and the second accommodating portion 14. The second compression spring 29 urges the exhaust valve 27 from the exhaust port 12 toward the second accommodating portion 14. As a result, the exhaust valve 27 comes into contact with the cylinder head 10 as shown in FIG. 1 and shuts off between the exhaust port 12 and the cylinder 20.

The valve mechanism 300 of the internal combustion engine 200 has an intake camshaft 40 and an exhaust camshaft 50 extending in the cylinder arrangement direction. A plurality of intake cams 41 arranged in the axial direction (depth direction in FIG. 1) of the intake camshaft 40 are connected to the intake camshaft 40. The intake cam 41 is arranged at a position corresponding to the intake valve 24 provided in each cylinder 20.

As shown in FIG. 2, the intake cam 41 includes a pair of large cams 42 and a small cam 43 arranged between the pair of large cams 42. The pair of large cams 42 have the same shape, and these cam ridges 42A have a shape that protrudes larger than the cam ridges 43A of the small cams 43.

Further, as shown in FIG. 1, a plurality of exhaust cams 51 arranged in the axial direction of the exhaust camshaft 50 are connected to the exhaust camshaft 50. The exhaust cam 51 is arranged at a position corresponding to the exhaust valve 27 provided in each cylinder 20. The exhaust cam 51 is composed of one cam having a cam crest having a predetermined shape.

The intake camshaft 40 and the exhaust camshaft 50 are mounted on a cam housing 30 connected to the upper end of the cylinder head 10. A cam cap 31 is connected to the cam housing 30 so as to cover the upper ends of the intake camshaft 40 and the exhaust camshaft 50. The cam cap 31 is fastened to the cam housing 30 by a plurality of bolts 33. The intake camshaft 40 and the exhaust camshaft 50 are rotatably supported by the cam housing 30 and the cam cap 31. The internal combustion engine 200 is provided with a cylinder head cover 32 connected to the upper end of the cam housing 30.

The valve operation mechanism 300 has a lash adjuster 60 held by the holding portion 16 of the cylinder head 10. A plurality of lash adjusters 60 are arranged at positions corresponding to the intake valve 24 and the exhaust valve 27. The lash adjuster 60 has an adjuster main body 61 embedded in the holding portion 16 of the cylinder head 10 and a plunger 62 provided so as to be able to appear and disappear with respect to the adjuster main body 61.

The valve mechanism 300 has a plurality of intake side rocker arms 70 whose one end is supported by the lash adjuster 60 and the other end is supported by the intake valve 24. The intake side rocker arm 70 is in contact with the intake cam 41 of the intake camshaft 40. In the large cam 42 and the small cam 43, the portion of the cam base circle is in contact with the intake side rocker arm 70, respectively.

The valve mechanism 300 also has a plurality of exhaust side rocker arms 170, one end of which is supported by the lash adjuster 60 and the other end of which is supported by the exhaust valve 27. The exhaust side rocker arm 170 is in contact with the exhaust cam 51 of the exhaust camshaft 50. The exhaust side rocker arm 170 is pressed by the cam ridge of the exhaust cam 51, so that the other end is swung downward with one end as the center. As a result, the exhaust valve 27 is driven, the exhaust port 12 and the cylinder 20 communicate with each other, and the exhaust gas is discharged from the cylinder 20 to the exhaust port 12.

The configuration of the intake side rocker arm 70 will be described.
The intake side rocker arm 70 has an arm portion 80 for pushing down the intake valve 24.

As shown in FIG. 3, the arm portion 80 has an inner arm 90 and an outer arm 100 provided so as to be tiltable with respect to the inner arm 90.
As shown in FIG. 4, the inner arm 90 connects the support end portion 91 that abuts on the lash adjuster 60, the swing end portion 92 that the intake valve 24 abuts, and the support end portion 91 and the swing end portion 92. It has a roller holding portion 93 and a roller holding portion 93.

As shown in FIG. 5, the support end portion 91 is formed with an adjuster hole portion 91A having a hemispherically curved shape toward the upper side. The upper end of the plunger 62 of the lash adjuster 60 is inserted into the adjuster hole 91A. As a result, the support end 91 of the inner arm 90 is supported by the lash adjuster 60. As shown in FIG. 4, the roller holding portion 93 has a pair of inner side walls 94. Support holes 94A arranged coaxially are formed in the pair of inner side walls 94. A roller shaft 95 is inserted through the support hole 94A. The roller shaft 95 projects outward from the pair of inner side walls 94. As shown in FIGS. 4 and 5, the roller shaft 95 is rotatably supported by the roller 97 via a ball bearing 96. The rollers 97 are arranged between the pair of inner side walls 94. The swing end portion 92 connects a pair of inner side walls 94. A flat locking surface 92A is formed on the upper end surface of the rocking end portion 92. Further, as shown in FIG. 5, a valve hole 92B having an open lower end is formed at the lower end of the swing end 92. The valve hole 92B is formed in a cylindrical shape. The upper end of the intake valve 24 is inserted into the valve hole 92B. As a result, the swing end 92 of the inner arm 90 is supported by the intake valve 24.

As shown in FIG. 6, the outer arm 100 has a fulcrum end portion 101, a pair of outer side walls 102 extending from the fulcrum end portion 101, and a tilting end portion 103 connecting the pair of outer side walls 102. There is. As shown in FIG. 5, the fulcrum end 101 is placed on the support end 91 of the inner arm 90. At the fulcrum end portion 101, a tilting hole portion 101A having a hemispherically curved shape is formed. The inner peripheral surface of the tilted hole portion 101A is in contact with the outer peripheral surface of the adjuster hole portion 91A. As shown in FIG. 3, the pair of outer side walls 102 are separated from each other, and the distance between them is set so that the pair of inner side walls 94 of the inner arm 90 can be arranged between them. The tilting end portion 103 has a connecting portion 104 connecting the pair of outer side walls 102, and a plate-shaped support wall 105 extending downward from the connecting portion 104. As shown in FIG. 5, the connecting portion 104 is arranged above the swinging end portion 92 of the inner arm 90, and the lower surface of the connecting portion 104 and the locking surface 92A of the swinging end portion 92 face each other. There is. Further, the tip portion of the connecting portion 104 extends outward from the swinging end portion 92, and the lower end of the support wall 105 extending downward from the tip portion is arranged below the locking surface 92A. ing. A pin hole 105A is formed in the support wall 105.

The intake side rocker arm 70 is switched between a locked state in which the relative tilt between the inner arm 90 and the outer arm 100 is restricted, and an unlocked state in which the relative tilt between the inner arm 90 and the outer arm 100 is allowed. It is equipped with a possible switching mechanism 110.

As shown in FIG. 1, the switching mechanism 110 has an operation shaft 120 extending in the same direction as the axial direction of the intake camshaft 40. A swing plate 130 arranged side by side at a position corresponding to the intake side rocker arm 70 is connected to the operation shaft 120. Further, the switching mechanism 110 has a motor 140 as an actuator for rotating the operation shaft 120.

As shown in FIG. 7, the operation shaft 120 is arranged coaxially with the first shaft 121 connected to the drive shaft 140A of the motor 140 and the first shaft 121, and the first shaft 121 is inserted therethrough. It has a second shaft 122 having an insertion hole 122A. In the first shaft 121, the other end (right end in FIG. 7) opposite to one end (left end in FIG. 7) to which the drive shaft 140A of the motor 140 is connected is the insertion hole 122A of the second shaft 122. It is inserted in. The first shaft 121 penetrates the insertion hole 122A of the second shaft 122, and the other end surface of the other end of the first shaft 121 and the other end of the second shaft 122 on the motor 140 side are opposite to each other. Is flush with the end face of. At one end of the first shaft 121, a first support piece 121A arranged on the motor 140 side and a second support piece 121B arranged on the second shaft 122 side are formed. The first support piece 121A and the second support piece 121B are formed in a shape that partially protrudes outward in the radial direction in the first shaft 121. At one end of the second shaft 122, a third support piece 122B formed in a shape partially protruding outward in the radial direction is formed. As shown in FIG. 7, in a state where the first shaft 121 is inserted through the second shaft 122, the first torsion spring 123 as an elastic member is connected to the first shaft 121 and the second shaft 122. The first torsion spring 123 has an eleventh fixed end 123A connected to a second support piece 121B of the first shaft 121 and a second coil extending from the eleventh fixed end 123A in the circumferential direction of the first shaft 121. It has one coil portion 123B. Further, the first torsion spring 123 has a twelfth fixed end 123C extending from the first coil portion 123B toward the outer peripheral side of the second shaft 122 and connected to the third support piece 122B of the second shaft 122. The first torsion spring 123 holds the eleventh fixed end 123A and the twelfth fixed end 123C so as to be arranged at a predetermined angle when no external force is applied. As a result, the relative phases of the first shaft 121 and the second shaft 122 are maintained at predetermined phases. On the other hand, when a torque Tr larger than the minimum torque T1 required for elastically deforming the first torsion spring 123 acts, the angle between the 11th fixed end 123A and the 12th fixed end 123C changes from the predetermined angle. .. As a result, relative rotation between the first shaft 121 and the second shaft 122 is allowed.

Further, a second torsion spring 124 is connected to the operation shaft 120. The second torsion spring 124 has a 21st fixed end 124A connected to the first support piece 121A of the first shaft 121 and a second coil extending from the 21st fixed end 124A in the circumferential direction of the first shaft 121. It has two coil portions 124B. Further, the second torsion spring 124 has a 22nd fixed end 124C extending from the second coil portion 124B toward the outer peripheral side of the first shaft 121 and connected to the cam housing 30. The second torsion spring 124 holds the 21st fixed end 124A and the 22nd fixed end 124C so as to be arranged at a predetermined angle when no external force is applied. As a result, the phase of the first shaft 121 with respect to the cam housing 30 is maintained at a predetermined phase. On the other hand, when a torque Tr larger than the minimum torque T2 required for elastically deforming the second torsion spring 124 acts, the first shaft 121 rotates, and the 21st fixed end 124A and the 22nd fixed end 124C The angle changes from the predetermined angle. The spring constant K1 of the first torsion spring 123 is larger than the spring constant K2 of the second torsion spring 124 (K1> K2). That is, the minimum torque T1 required for elastically deforming the first torsional spring 123 is larger than the minimum torque T2 required for elastically deforming the second torsional spring 124.

The swing plate 130 is connected to the first shaft 121, and is provided corresponding to the intake side rocker arm 70A arranged at a position facing the outer peripheral surface of the first shaft 121 in the cylinder arrangement direction. 1 It has a rocking plate 131. Further, the swing plate 130 is connected to the second shaft 122 and is provided corresponding to the intake side rocker arm 70B arranged at a position facing the outer peripheral surface of the second shaft 122 in the cylinder arrangement direction. It has two second rocking plates 132.

Further, the switching mechanism 110 has connecting pins 150 arranged side by side at positions corresponding to the plurality of swing plates 130.
As shown in FIGS. 5 and 6, the connecting pin 150 is inserted into the pin hole 105A of the outer arm 100. The connecting pin 150 is locked by sandwiching the locking portion 151 which is formed in a columnar shape and is inserted through the pin hole 105A, the flange portion 152 whose diameter is larger than that of the locking portion 151, and the flange portion 152. It is composed of an urging portion 153 arranged on the opposite side of the portion 151. The tip of the urging portion 153 is formed in a hemispherical shape. A pressing spring 160 is arranged between the flange portion 152 of the connecting pin 150 and the support wall 105. The pressing spring 160 urges the connecting pin 150 in the direction of projecting from the pin hole 105A of the support wall 105 (to the right in FIG. 5). A torsion spring 98 (see FIG. 11) is attached to each of both ends of the roller shaft 95 of the inner arm 90. In the torsion spring 98, when the outer arm 100 is placed on the inner arm 90 and assembled to each other as shown in FIG. 3, the swing end portion 92 of the inner arm 90 is from the tilting end portion 103 of the outer arm 100. The outer arm 100 is urged so as to be separated. As a result, the connecting pin 150 is inserted between the locking surface 92A of the swinging end portion 92 and the lower surface of the connecting portion 104 of the tilting end portion 103 in a state where the intake side rocker arm 70 is not pressed by the intake cam 41. A possible gap is formed.

As shown in FIG. 2, the pair of large cams 42 of the intake cam 41 are in contact with the outer arm 100, and the small cam 43 is in contact with the inner arm 90. As the intake camshaft 40 rotates, the intake side rocker arm 70 is pressed downward by the large cam 42 or the small cam 43. As a result, the intake side rocker arm 70 swings the other end supported by the intake valve 24 downward with one end supported by the lash adjuster 60 as a fulcrum. As a result, the intake valve 24 is driven, the intake port 11 and the cylinder 20 communicate with each other, and the air and fuel flowing through the intake port 11 are introduced into the cylinder 20.

In FIG. 8, the valve lift amount when the intake valve 24 is driven by the large cam 42 is shown by a solid line. Further, the valve lift amount when the intake valve 24 is driven by the small cam 43 is shown by the alternate long and short dash line. As shown in FIG. 8, in the intake cam 41, the maximum valve lift amount VLm1 when the intake valve 24 is driven by the large cam 42 is larger than the maximum valve lift amount VLm2 when the intake valve 24 is driven by the small cam 43. The shape of the cam ridge 42A of the large cam 42 and the shape of the cam ridge 43A of the small cam 43 are designed so as to be large. Further, the shape of the cam ridge 43A of the small cam 43 is set so that a gradual change period Cm1 in which the decrease in the valve lift amount is small is provided immediately before the valve lift amount becomes zero. The valve opening period OV1 of the intake valve 24 when driven by the large cam 42 is shorter than the valve opening period OV2 of the intake valve 24 when driven by the small cam 43.

As shown in FIG. 9, when the connecting pin 150 protrudes from the support wall 105 and is not arranged between the locking surface 92A of the rocking end 92 and the lower surface of the connecting 104 of the tilting end 103, The unlocked state allows relative tilting of the inner arm 90 and the outer arm 100. The position of the connecting pin 150 at this time is called the second position. In this state, as shown in FIG. 9, when the small cam 43 of the intake cam 41 presses the roller 97 of the inner arm 90 and the large cam 42 of the intake cam 41 presses the outer side wall 102 of the outer arm 100, the large cam The outer arm 100 is tilted with respect to the inner arm 90 by the difference in shape between the cam ridge 42A of the 42 and the cam ridge 43A of the small cam 43. In this state, the force pressed by the outer arm 100 by the large cam 42 is not transmitted to the inner arm 90, and the intake side rocker arm 70 swings by the small cam 43. As a result, the intake valve 24 is driven with a valve lift amount corresponding to the shape of the cam ridge 43A of the small cam 43.

On the other hand, as shown in FIG. 10, when the connecting pin 150 is inserted into the support wall 105 against the urging force of the pressing spring 160, the locking portion 151 of the connecting pin 150 locks the swing end portion 92. It is arranged between the surface 92A and the lower surface of the connecting portion 104 of the tilting end portion 103. As a result, the intake side rocker arm 70 is in a locked state in which the relative tilt of the inner arm 90 and the outer arm 100 is restricted. The position of the connecting pin 150 at this time is called the first position. When the position of the connecting pin 150 is the first position, when the large cam 42 comes into contact with the outer arm 100 as the intake camshaft 40 rotates, the force from the large cam 42 is transmitted to the inner arm 90. , The inner arm 90 swings together with the outer arm 100. As a result, the intake side rocker arm 70 swings with the large cam 42. As a result, the intake valve 24 is driven with a valve lift amount corresponding to the shape of the cam ridge 42A of the large cam 42. While the intake side rocker arm 70 is swinging, the holding force between the inner arm 90 and the outer arm 100 becomes larger than the urging force of the pressing spring 160, so that the connecting pin 150 is the inner arm 90 and the outer arm. It is sandwiched between 100 and held in the first position. After that, when the swing of the intake side rocker arm 70 is completed, the pressing force from the intake cam 41 decreases, so that the locking surface 92A of the swing end portion 92 and the tilt end portion 103 are connected by the urging force of the torsion spring 98. The lower surface of the portion 104 is separated from the lower surface, and the holding force acting on the connecting pin 150 becomes smaller than the urging force of the pressing spring 160. As a result, the connecting pin 150 is disengaged from between the inner arm 90 and the outer arm 100 and returns to the second position.

In the present embodiment, the position of the connecting pin 150 on the intake side rocker arm 70 is switched from the second position to the first position as follows.
As schematically shown in FIG. 11, in the operation shaft 120, the first swing plate 131 is connected to the first shaft 121, and the second swing plate 132 is connected to the second shaft 122. In the axial view shown in FIG. 11, the first swing plate 131 is arranged at positions where the phases of the second swing plate 132 and the operation shaft 120 in the circumferential direction are different from each other. When the operation shaft 120 is rotated by the motor 140 in the clockwise direction indicated by the arrow in FIG. 11, the spring constant K1 of the first torsion spring 123 is larger than the spring constant K2 of the second torsion spring 124, so that the motor 140 First, the second torsion spring 124 is compressed by the torque of. As a result, in the operation shaft 120, both the first shaft 121 and the second shaft 122 rotate while maintaining a predetermined relative phase. The second swing plate 132 is arranged in front of the first swing plate 131 in the rotation direction of the operation shaft 120. Therefore, when the operation shaft 120 rotates, the second swing plate 132 comes into contact with the connecting pin 150 of the intake side rocker arm 70B arranged at a position corresponding to the second swing plate 132.

As shown in FIG. 12, when the operation shaft 120 further rotates from this state, the second swing plate 132 inserts the connecting pin 150 into the support wall 105 against the urging force of the pressing spring 160. The tip of the second swing plate 132 comes into contact with the stopper wall portion 30A provided on the cam housing 30, and further movement is restricted. As a result, the states of the two intake side rocker arms 70B are switched from the unlocked state to the locked state.

In the switching mechanism 110, the first shaft 121 is rotated by further applying torque from this state by the motor 140. In this state, the second shaft 122 does not rotate, and the first shaft 121 rotates while compressing both the first torsion spring 123 and the second torsion spring 124. In this way, the rotation of the first shaft 121 causes the first swing plate 131 to abut on the connecting pin 150 of the intake side rocker arm 70A arranged at the position corresponding to the first swing plate 131.

As shown in FIG. 13, when the first shaft 121 further rotates from this state, the first swing plate 131 inserts the connecting pin 150 into the support wall 105 against the urging force of the pressing spring 160. As a result, the position of the connecting pin 150 in the intake side rocker arm 70A arranged at the position corresponding to the first swing plate 131 is switched from the second position to the first position, and the states of all the intake side rocker arms 70 are locked. It becomes a state. The switching mechanism 110 controls the rotation of the operation shaft 120 by controlling the duty of the voltage applied to the motor 140.

As shown in FIG. 14, the rotation angle of the motor 140 is determined according to the torque generated by the motor 140. That is, when the torque generated by the motor 140 is smaller than the minimum torque T2 required for elastically deforming the second torsion spring 124, the motor 140 does not rotate and the operation shaft 120 is set by the second torsion spring 124. It is held in a predetermined phase. As a result, the swing plate 130 is arranged at a position separated from the connecting pin 150. When the generated torque of the motor 140 becomes larger than the torque T2 required for elastically deforming the second torsion spring 124, the rotation angle of the motor 140 increases as the generated torque of the motor 140 increases. That is, both the first shaft 121 and the second shaft 122 are in a state of rotation. When the rotation angle of the motor 140 becomes the rotation angle θ1 in which the second swing plate 132 abuts on the stopper wall portion 30A, the torque generated by the motor 140 is increased until the torque T3 at which the first torsion spring 123 starts to be compressed is reached. Even if it increases, it becomes a dead zone region where the rotation angle of the motor 140 does not change. The spring constant K1 of the first torsion spring 123 and the spring constant K2 of the second torsion spring 124 are designed so that the generated torque when the voltage control duty ratio is 50% is the center position of the dead zone region. There is. When the generated torque of the motor 140 becomes larger than the torque T3 at which the second torsion spring 124 starts to be compressed, the rotation angle of the motor 140 becomes large beyond the dead zone region. At this time, both the first torsion spring 123 and the second torsion spring 124 are elastically deformed. As a result, only the first shaft 121 rotates and the second shaft 122 does not rotate.

In the present embodiment, when the intake side rocker arm 70B arranged at the position corresponding to the second swing plate 132 is not pressed by the intake cam 41 and is not swinging, it is applied to the motor 140. The voltage control duty ratio is controlled to 50%. As a result, the state of the two intake side rocker arms 70B arranged at the positions corresponding to the second swing plate 132 is locked. After that, when the intake side rocker arm 70A arranged at the position corresponding to the first swing plate 131 is not pressed by the intake cam 41 and is not swinging, the voltage applied to the motor 140. Control duty ratio is controlled to 100%. As a result, the states of the two intake-side rocker arms 70A arranged at the positions corresponding to the first swing plate 131 are locked. Further, by controlling the control duty ratio of the voltage applied to the motor 140 to 0%, the operation shaft 120 is initially driven by the motor 140 by the urging force of the first torsion spring 123 and the second torsion spring 124. It is rotated to the state, and the state of the intake side rocker arm 70 is set to the unlocked state. As described above, in the present embodiment, the state of the intake side rocker arm 70 is switched by controlling the control duty ratio of the voltage applied to the motor 140 in three patterns of 0%, 50%, and 100%.

The operation and effect of this embodiment will be described.
(1) In the present embodiment, a plurality of connecting pins 150 can be operated by driving the motor 140 of the switching mechanism 110 to displace the swing plate 130 connected to the operation shaft 120. This makes it possible to switch the states of a plurality of intake side rocker arms 70 with one actuator. Therefore, the number of actuators of the switching mechanism 110 can be reduced as compared with the configuration in which the state of one intake side rocker arm 70 is switched by one actuator.

(2) In the present embodiment, the first shaft 121 and the second shaft 122 are connected by a first torsion spring 123 so as to be relatively rotatable. The first shaft 121 is connected to the cam housing 30 by a second torsion spring 124. The first swing plate 131 is connected to the first shaft 121, and the second swing plate 132 is connected to the second shaft 122. The second swing plate 132 is arranged in front of the first swing plate 131 in the rotation direction when the operation shaft 120 is rotated by the motor 140. The spring constant K1 of the first torsion spring 123 is larger than the spring constant K2 of the second torsion spring 124. Therefore, in the process of rotating the operation shaft 120, the second swing plate 132 first comes into contact with the connecting pin 150. After that, by rotating the first shaft 121 to elastically deform the first torsion spring 123, only the first shaft 121 is further rotated and the first swing plate 131 comes into contact with the connecting pin 150. In this way, the timing at which the first swing plate 131 abuts on the connecting pin 150 and the timing at which the second swing plate 132 abuts on the connecting pin 150 can be made different. Therefore, the states of the plurality of intake side rocker arms 70 can be switched at different timings instead of being switched at the same timing.

(3) The spring constant K1 of the first torsion spring 123 and the spring constant K2 of the second torsion spring 124 so that the output torque when the control duty ratio of the applied voltage of the motor 140 becomes 50% is the center position of the dead zone region. Is designing. Therefore, even if the generated torque of the motor 140 fluctuates due to the variation in the control duty ratio, the influence is not easily reflected in the rotation angle when it is in the dead zone region. Therefore, even if the control accuracy of the generated torque of the motor 140 is not set high, the control state for rotating the first shaft 121 and the second shaft 122 and the control for rotating the first shaft 121 and not rotating the second shaft 122. It becomes easy to separate from the state, and it becomes easy to secure the control accuracy of the operation shaft 120. Therefore, it is possible to control the motor 140 by a simple method such as feed forward control.

(Second Embodiment)
A second embodiment of the valve operating mechanism will be described with reference to FIGS. 15 to 18. In the present embodiment, the configuration of the switching mechanism is different from that of the first embodiment. The same configurations as those of the first embodiment are designated by a common reference numeral, and the description thereof will be omitted. In this embodiment, an internal combustion engine in which ignition is executed in the order of the first cylinder # 1, the third cylinder # 3, the fourth cylinder # 4, and the second cylinder # 2 will be described as an example.

As shown in FIG. 15, the operation shaft 410 of the switching mechanism 400 has four split shafts 420 having the same number of cylinders as the internal combustion engine 200. The split shafts 420 are arranged coaxially with each other. In the split shaft 420, the central shaft 425 arranged on the innermost peripheral side is connected to the drive shaft 140A of the motor 140. The central shaft 425 is inserted through a plurality of outer shafts 430 arranged so as to overlap each other on the outer peripheral side of the central shaft 425. The outer shaft 430 is composed of three divided shafts 420, and is arranged in the order of the first outer shaft 431, the second outer shaft 432, and the third outer shaft 433 from the inner peripheral side.

The first outer shaft 431 is formed with a first insertion hole 431A penetrating in the axial direction. In the central shaft 425, the other end (right end in FIG. 15) opposite to one end (left end in FIG. 15) to which the drive shaft 140A of the motor 140 is connected is the first insertion of the first outer shaft 431. It is inserted through the hole 431A. The central shaft 425 penetrates the first insertion hole 431A of the first outer shaft 431, and the end surface of the other end of the central shaft 425 and the other side opposite to the one end of the first outer shaft 431 on the motor 140 side. It is flush with the end face of the end. At one end of the central shaft 425, a first support piece 425A arranged on the motor 140 side and a second support piece 425B arranged on the first outer shaft 431 side are formed. The first support piece 425A and the second support piece 425B are formed in a shape that partially protrudes outward in the radial direction on the central shaft 425.

The second outer shaft 432 is formed with a second insertion hole 432A penetrating in the axial direction. The other end of the first outer shaft 431 is inserted into the second insertion hole 432A of the second outer shaft 432. The first outer shaft 431 penetrates the second insertion hole 432A of the second outer shaft 432, and the end surface of the other end of the first outer shaft 431 and one end of the second outer shaft 432 on the motor 140 side are It is flush with the end face of the other end on the opposite side. At one end of the second outer shaft 432, a third support piece 431B arranged on the motor 140 side and a fourth support piece 431C arranged on the second outer shaft 432 side are formed. The third support piece 431B and the fourth support piece 431C are formed in a shape that partially protrudes outward in the radial direction in the first outer shaft 431.

The second outer shaft 432 is formed with a fifth support piece 432B arranged on the motor 140 side and a sixth support piece 432C arranged on the side away from the motor 140 from the fifth support piece 432B. .. The fifth support piece 432B and the sixth support piece 432C are formed in a shape that partially protrudes outward in the radial direction in the second outer shaft 432.

The third outer shaft 433 is formed with a third insertion hole 433A penetrating in the axial direction. The portion of the second outer shaft 432 between the fifth support piece 432B and the sixth support piece 432C is inserted into the third insertion hole 433A of the third outer shaft 433. In the second outer shaft 432, the portion where the fifth support piece 432B is formed is arranged closer to the motor 140 than the third outer shaft 433, and the portion where the sixth support piece 432C is formed is the third outer shaft 433. It is arranged on the side away from the motor 140. The third outer shaft 433 is formed with a seventh support piece 433B at the other end on the opposite side to the one end on the motor 140 side. The seventh support piece 433B is formed in the third outer shaft 433 in a shape that partially protrudes outward in the radial direction.

A central shaft 425 is inserted into the first insertion hole 431A of the first outer shaft 431, the second insertion hole 432A of the second outer shaft 432, and the third insertion hole 433A of the third outer shaft 433.

In a state where the central shaft 425 is inserted through the first outer shaft 431, a first torsion spring 440 as an elastic member is connected to the central shaft 425 and the first outer shaft 431. That is, in the relationship between the central shaft 425 and the first outer shaft 431, the central shaft 425 is the inner peripheral side shaft arranged on the inner peripheral side, and the first outer shaft 431 is arranged on the outer peripheral side of the inner peripheral side shaft. It becomes the outer peripheral side shaft. The first torsion spring 440 has an eleventh fixed end 440A connected to a second support piece 425B of the central shaft 425 and a first coil extending in a coil shape from the eleventh fixed end 440A in the circumferential direction of the central shaft 425. It has a portion 440B. Further, the first torsion spring 440 extends from the first coil portion 440B to the outer peripheral side of the first outer shaft 431, and has a twelfth fixed end 440C connected to the third support piece 431B of the first outer shaft 431. Have. The first torsion spring 440 holds the eleventh fixed end 440A and the twelfth fixed end 440C so as to be arranged at a predetermined angle when no external force is applied. As a result, the relative phases of the central shaft 425 and the first outer shaft 431 are maintained at predetermined phases. On the other hand, when a torque Tr larger than the minimum torque T4 required for elastically deforming the first torsion spring 440 acts, the angle between the 11th fixed end 440A and the 12th fixed end 440C changes from the above predetermined angle. .. As a result, relative rotation between the central shaft 425 and the first outer shaft 431 is allowed.

In a state where the first outer shaft 431 is inserted into the second outer shaft 432, a second torsion spring 441 as an elastic member is connected to the first outer shaft 431 and the second outer shaft 432. That is, in the relationship between the first outer shaft 431 and the second outer shaft 432, the first outer shaft 431 is an inner peripheral side shaft arranged on the inner peripheral side, and the second outer shaft 432 is the outer peripheral side of the inner peripheral side shaft. It becomes the outer peripheral side shaft arranged in. The second torsion spring 441 extends from the 21st fixed end 441A connected to the 4th support piece 431C of the first outer shaft 431 and the 21st fixed end 441A in a coil shape in the circumferential direction of the first outer shaft 431. It has a second coil portion 441B and the like. Further, the second torsion spring 441 extends from the second coil portion 441B to the outer peripheral side of the second outer shaft 432, and has a 22nd fixed end 441C connected to the fifth support piece 432B of the second outer shaft 432. Have. The second torsion spring 441 holds the 21st fixed end 441A and the 22nd fixed end 441C so as to be arranged at a predetermined angle when no external force is applied. As a result, the relative phases of the first outer shaft 431 and the second outer shaft 432 are maintained at predetermined phases. On the other hand, when a torque Tr larger than the minimum torque T5 required for elastically deforming the second torsion spring 441 acts, the angle between the 21st fixed end 441A and the 22nd fixed end 441C changes from the above predetermined angle. .. As a result, relative rotation between the first outer shaft 431 and the second outer shaft 432 is allowed.

In a state where the second outer shaft 432 is inserted through the third outer shaft 433, a third torsion spring 442 as an elastic member is connected to the second outer shaft 432 and the third outer shaft 433. That is, in the relationship between the second outer shaft 432 and the third outer shaft 433, the second outer shaft 432 is the inner peripheral side shaft arranged on the inner peripheral side, and the third outer shaft 433 is the outer peripheral side of the inner peripheral side shaft. It becomes the outer peripheral side shaft arranged in. The third torsion spring 442 extends from the 31st fixed end 442A connected to the 6th support piece 432C of the 2nd outer shaft 432 and the 31st fixed end 442A in a coil shape in the circumferential direction of the 2nd outer shaft 432. It has a third coil portion 442B and the like. Further, the third torsion spring 442 extends from the third coil portion 442B to the outer peripheral side of the third outer shaft 433, and has a 32nd fixed end 442C connected to the seventh support piece 433B of the third outer shaft 433. Have. The third torsion spring 442 holds the 31st fixed end 442A and the 32nd fixed end 442C so as to be arranged at a predetermined angle when no external force is applied. As a result, the relative phases of the second outer shaft 432 and the third outer shaft 433 are maintained at predetermined phases. On the other hand, when a torque Tr larger than the minimum torque T6 required for elastically deforming the third torsion spring 442 acts, the angle between the 31st fixed end 442A and the 32nd fixed end 442C changes from the above predetermined angle. .. As a result, relative rotation between the second outer shaft 432 and the third outer shaft 433 is allowed.

Further, a fourth torsion spring 443 is connected to the central shaft 425. The fourth torsion spring 443 has a 41st fixed end 443A connected to the first support piece 425A of the central shaft 425 and a fourth coil extending in a coil shape from the 41st fixed end 443A in the circumferential direction of the central shaft 425. It has a portion 443B. Further, the fourth torsion spring 443 has a 42nd fixed end 443C extending from the fourth coil portion 443B toward the outer peripheral side of the central shaft 425 and connected to the cam housing 30. The fourth torsion spring 443 holds the 41st fixed end 443A and the 42nd fixed end 443C so as to be arranged at a predetermined angle when no external force is applied. As a result, the phase of the central shaft 425 with respect to the cam housing 30 is maintained at a predetermined phase. On the other hand, when a torque Tr larger than the minimum torque T7 required for elastically deforming the fourth torsion spring 443 acts, the central shaft 425 rotates and the angle between the 41st fixed end 443A and the 42nd fixed end 443C Changes from the above-mentioned predetermined angle. The spring constant K4 of the first torsion spring 440 is larger than the spring constant K5 of the second torsion spring 441. The spring constant K5 of the second torsion spring 441 is larger than the spring constant K6 of the third torsion spring 442. The spring constant K6 of the third torsion spring 442 is larger than the spring constant K7 of the fourth torsion spring 443 (K4> K5> K6> K7). That is, the minimum torque T4 required for elastically deforming the first torsional spring 440 is larger than the minimum torque T5 required for elastically deforming the second torsional spring 441. Further, the minimum torque T5 required for elastically deforming the second torsion spring 441 is larger than the minimum torque T6 required for elastically deforming the third torsion spring 442. Further, the minimum torque T6 required for elastically deforming the third torsion spring 442 is larger than the minimum torque T7 required for elastically deforming the fourth torsion spring 443.

The rocking plate 450 is connected to the other end of the second outer shaft 432 and is arranged at a position facing the outer peripheral surface of the second outer shaft 432 in the cylinder arrangement direction on the intake side of the first cylinder # 1. It has a first swing plate 451 provided corresponding to the rocker arm 70A. The swing plate 450 corresponds to the intake side rocker arm 70B of the second cylinder # 2, which is connected to the third outer shaft 433 and is arranged at a position facing the outer peripheral surface of the third outer shaft 433 in the cylinder arrangement direction. It has a second rocking plate 452 provided in the above. Further, the rocking plate 450 is connected to one end of the first outer shaft 431 and is arranged at a position facing the outer peripheral surface of the first outer shaft 431 in the cylinder arrangement direction. It has a third swing plate 453 provided corresponding to the side rocker arm 70C. The swing plate 450 is connected to the central shaft 425 and is provided corresponding to the intake side rocker arm 70D of the fourth cylinder # 4 which is arranged at a position facing the outer peripheral surface of the central shaft 425 in the cylinder arrangement direction. It also has a fourth rocking plate 454. In this way, the swing plate 450 is connected to each of the plurality of split shafts 420.

Further, the switching mechanism 400 has connecting pins 150 arranged side by side at positions corresponding to the swing plate 450.
As schematically shown in FIG. 16, in the operation shaft 410, in the axial view thereof, the first swing plate 451, the second swing plate 452, the third swing plate 453, and the fourth swing plate 454 Each is arranged at a position where the phase of the operation shaft 410 in the circumferential direction is different. The operating shaft 410 is rotated by the motor 140 in the clockwise direction indicated by the arrow in FIG. The swing plate 450 is arranged at equal intervals in the order of the second swing plate 452, the first swing plate 451, the third swing plate 453, and the fourth swing plate 454 from the front side in the rotation direction of the operation shaft 410. Have been placed. When the operating shaft 410 rotates, the torque of the motor 140 first compresses the fourth torsion spring 443 having the smallest spring constant. As a result, in the operation shaft 410, both the central shaft 425 and the outer shaft 430 rotate while maintaining a predetermined relative phase. Then, the second swing plate 452 comes into contact with the connecting pin 150 of the intake side rocker arm 70B arranged at the position corresponding to the second swing plate 452. Then, the position of the connecting pin 150 is switched from the second position to the first position by pressing the connecting pin 150 of the intake side rocker arm 70B by the second swing plate 452. As a result, the state of the intake side rocker arm 70B is switched from the unlocked state to the locked state. In this state, the tip end portion of the second swing plate 452 abuts on the stopper wall portion (not shown), and further movement is restricted.

In the switching mechanism 400, torque is further applied to the central shaft 425 by the motor 140 from this state. As a result, the third torsion spring 442, which has the smallest spring constant next to the fourth torsion spring 443, is compressed. In this state, the third outer shaft 433 does not rotate, and the central shaft 425, the first outer shaft 431, and the second outer shaft 432 rotate while compressing both the third torsion spring 442 and the fourth torsion spring 443. do. As a result, the first swing plate 451 comes into contact with the connecting pin 150 of the intake side rocker arm 70A arranged at the position corresponding to the first swing plate 451. Then, the position of the connecting pin 150 is switched from the second position to the first position by pressing the connecting pin 150 of the intake side rocker arm 70A by the first swing plate 451. As a result, the state of the intake side rocker arm 70A is switched from the unlocked state to the locked state. In this state, the tip end portion of the first swing plate 451 abuts on the stopper wall portion (not shown), and further movement is restricted.

In the switching mechanism 400, torque is further applied to the central shaft 425 by the motor 140 from this state. As a result, the second torsion spring 441 having the next smallest spring constant after the third torsion spring 442 is compressed. In this state, the second outer shaft 432 and the third outer shaft 433 do not rotate, and the central shaft 425 and the first outer shaft 431 rotate while compressing both the second torsion spring 441 and the fourth torsion spring 443. do. As a result, the third swing plate 453 comes into contact with the connecting pin 150 of the intake side rocker arm 70C arranged at the position corresponding to the third swing plate 453. Then, the position of the connecting pin 150 is switched from the second position to the first position by pressing the connecting pin 150 of the intake side rocker arm 70C by the third swing plate 453. As a result, the state of the intake side rocker arm 70C is switched from the unlocked state to the locked state. In this state, the tip end portion of the third swing plate 453 comes into contact with the stopper wall portion (not shown), and further movement is restricted.

In the switching mechanism 400, torque is further applied to the central shaft 425 by the motor 140 from this state. As a result, the first torsion spring 440, which has the smallest spring constant next to the second torsion spring 441, is compressed. In this state, the first outer shaft 431, the second outer shaft 432, and the third outer shaft 433 do not rotate, and only the center shaft 425 rotates while compressing both the first torsion spring 440 and the fourth torsion spring 443. do. As a result, the fourth swing plate 454 comes into contact with the connecting pin 150 of the intake side rocker arm 70D arranged at the position corresponding to the fourth swing plate 454. Then, the position of the connecting pin 150 is switched from the second position to the first position by pressing the connecting pin 150 of the intake side rocker arm 70D by the fourth swing plate 454. As a result, the state of the intake side rocker arm 70D is switched from the unlocked state to the locked state.

As shown in FIG. 17, the rotation angle of the motor 140 is determined according to the torque generated by the motor 140. That is, when the torque generated by the motor 140 is smaller than the minimum torque T7 required for elastically deforming the fourth torsion spring 443, the motor 140 does not rotate and the operation shaft 410 is set by the fourth torsion spring 443. It is held in a predetermined phase. As a result, the swing plate 450 is arranged at a position separated from the connecting pin 150. When the generated torque of the motor 140 becomes larger than the torque T7 required for elastically deforming the fourth torsion spring 443, the rotation angle of the motor 140 increases as the generated torque of the motor 140 increases. That is, the operation shaft 410 is in a state of rotation. When the rotation angle of the motor 140 becomes the rotation angle θ2 at which the second swing plate 452 abuts on the stopper wall portion, the torque generated by the motor 140 increases until the torque T8 at which the third torsion spring 442 starts to be compressed is reached. Even so, it is the first dead zone region where the rotation angle of the motor 140 does not change. The spring constant K6 of the third torsion spring 442 and the spring constant K7 of the fourth torsion spring 443 have the torque generated when the control duty ratio of the voltage applied to the motor 140 is 25% at the center of the first dead zone region. It is designed to be in position. When the torque generated by the motor 140 becomes larger than the torque T8 at which the third torsion spring 442 starts to be compressed, the rotation angle of the motor 140 increases beyond the first dead zone region. At this time, both the third torsion spring 442 and the fourth torsion spring 443 are elastically deformed. As a result, the central shaft 425, the first outer shaft 431, and the second outer shaft 432 rotate, and the third outer shaft 433 does not rotate.

After that, when the rotation angle of the motor 140 becomes the rotation angle θ3 at which the first swing plate 451 abuts on the stopper wall portion, the torque generated by the motor 140 increases until the torque T9 at which the second torsion spring 441 starts to be compressed is reached. Even so, it becomes the second dead zone region where the rotation angle of the motor 140 does not change. The spring constant K5 of the second torsion spring 441 and the spring constant K7 of the fourth torsion spring 443 have the torque generated when the control duty ratio of the voltage applied to the motor 140 is 50% at the center of the second dead zone region. It is designed to be in position. When the generated torque of the motor 140 becomes larger than the torque T9 at which the second torsion spring 441 starts to be compressed, the rotation angle of the motor 140 becomes larger beyond the second dead zone region. At this time, both the second torsion spring 441 and the fourth torsion spring 443 are elastically deformed. As a result, the central shaft 425 and the first outer shaft 431 rotate, and the second outer shaft 432 and the third outer shaft 433 do not rotate.

After that, when the rotation angle of the motor 140 becomes the rotation angle θ4 at which the third swing plate 453 abuts on the stopper wall portion, the torque generated by the motor 140 increases until the torque T10 at which the first torsion spring 440 starts to be compressed is reached. Even so, it is a third dead zone region where the rotation angle of the motor 140 does not change. The spring constant K4 of the first torsion spring 440 and the spring constant K7 of the fourth torsion spring 443 have the torque generated when the control duty ratio of the voltage applied to the motor 140 is 75% at the center of the third dead zone region. It is designed to be in position. When the generated torque of the motor 140 becomes larger than the torque T10 at which the first torsion spring 440 starts to be compressed, the rotation angle of the motor 140 becomes larger beyond the third dead zone region. At this time, both the first torsion spring 440 and the fourth torsion spring 443 are elastically deformed. As a result, only the central shaft 425 rotates, and the first outer shaft 431, the second outer shaft 432, and the third outer shaft 433 do not rotate.

In the present embodiment, when the intake side rocker arm 70B arranged at the position corresponding to the second swing plate 452 is not pressed by the intake cam 41 and is not swinging, it is applied to the motor 140. The duty ratio of the voltage is controlled to 25%. As a result, the state of the intake side rocker arm 70B of the second cylinder # 2 is locked. After that, when the intake side rocker arm 70A arranged at the position corresponding to the first swing plate 451 is not pressed by the intake cam 41 and is not swinging, the voltage applied to the motor 140. Duty ratio is controlled to 50%. As a result, the state of the intake side rocker arm 70A of the first cylinder # 1 is locked. After that, when the intake side rocker arm 70C arranged at the position corresponding to the third swing plate 453 is not pressed by the intake cam 41 and is not swinging, the voltage applied to the motor 140. Duty ratio is controlled to 75%. As a result, the state of the intake side rocker arm 70C of the third cylinder # 3 is locked. After that, when the intake side rocker arm 70D arranged at the position corresponding to the fourth swing plate 454 is not pressed by the intake cam 41 and is not swinging, the voltage applied to the motor 140. Duty ratio is controlled to 100%. As a result, the state of the intake side rocker arm 70D of the fourth cylinder # 4 is locked. Further, by controlling the duty ratio of the voltage applied to the motor 140 to 0%, the operation shaft 410 is of the first torsion spring 440, the second torsion spring 441, the third torsion spring 442, and the fourth torsion spring 443. It is rotated to the initial state before being driven by the motor 140 by the urging force, and the state of the intake side rocker arm 70 is set to the unlocked state. As described above, in the switching mechanism 400 of the present embodiment, the duty ratio of the voltage applied to the motor 140 is controlled by five patterns of 0%, 25%, 50%, 75%, and 100% to control the motor. The state of the intake side rocker arm 70 is switched for each cylinder 20 by adjusting the torque applied to the central shaft 425 from 140.

In this embodiment, in addition to the same actions and effects as in (1) and (3) above, the following actions and effects can be obtained.
(4) In the present embodiment, the operation shaft 410 has a plurality of divided shafts 420 having the same number as the number of cylinders 20 of the internal combustion engine 200, and the divided shafts 420 are connected to each other by an elastic member so as to be relatively rotatable. A swing plate 450 is connected to each of the split shafts 420. In the rotation direction of the operation shaft 410 by the motor 140, the second swing plate 452, the first swing plate 451 and the third swing plate 453, and the fourth swing plate 454 are arranged at equal intervals in this order from the front side. Therefore, in the process of rotating the operation shaft 410, the swing plate 450 abuts on the connecting pin 150 in the above order. In this way, since the timing at which the swing plate 450 abuts on the connecting pin can be made different for each split shaft 420, the states of the plurality of intake side rocker arms 70 are not all switched at the same timing, but the cylinder 20 It is also possible to switch the state of the intake side rocker arm 70 at different timings each time.

(5) As shown in FIGS. 18A and 18B, in the internal combustion engine 200, the first cylinder # 1, the third cylinder # 3, the fourth cylinder # 4, and the second cylinder # 2 are ignited in this order. Is executed. That is, the intake side rocker arm 70 is driven in the order of the first cylinder # 1, the third cylinder # 3, the fourth cylinder # 4, and the second cylinder # 2. In the present embodiment, the state of the intake side rocker arm 70 is switched at different timings for each cylinder 20. In order to clarify the difference from such a configuration, first, in the first embodiment, the states of the two intake side rocker arms 70 provided in the first cylinder # 1 and the third cylinder # 3 are switched at the same timing, and the first A case where the states of the two intake side rocker arms 70 provided in the four cylinders # 4 and the second cylinder # 2 are switched at the same timing will be described.

In the first embodiment, when the states of the two intake side rocker arms 70 provided in the first cylinder # 1 and the third cylinder # 3 are switched at the same time, the states of the intake side rocker arms 70 can be switched at the same time. , Both of the two intake-side rocker arms 70 provided in the first cylinder # 1 and the third cylinder # 3 are not swinging. That is, the period P1 from the timing t1 when the swing of the intake side rocker arm 70A in the first cylinder # 1 ends to the timing t2 when the swing of the intake side rocker arm 70C in the third cylinder # 3 starts, and the third cylinder #. Switching is possible during the period P2 from the timing t3 when the swing of the intake side rocker arm 70C in 3 ends to the timing t4 when the swing of the intake side rocker arm 70A in the first cylinder # 1 starts. In this configuration, even during the period P3 in which the intake side rocker arm 70A does not swing from the end of the swing of the intake side rocker arm 70A in the first cylinder # 1 to the start of the next swing, the first While the intake side rocker arm 70C in the 3-cylinder # 3 is swinging, the states of the intake side rocker arms 70A and 70C cannot be switched. The same applies to the case where the states of the two intake side rocker arms 70B and 70D provided in the second cylinder # 2 and the fourth cylinder # 4 are switched at the same time.

In the present embodiment, the state of the intake side rocker arm 70 is switched for each cylinder 20. Therefore, for example, when the state of the intake side rocker arm 70A in the first cylinder # 1 is switched, the switching can be enabled within the period P3 regardless of the state of the intake side rocker arm 70 in the other cylinders. Therefore, it is possible to secure a long switchable time for the intake side rocker arm 70 in each cylinder 20.

Each of the above embodiments can be modified and implemented as follows. Each of the above embodiments and the following modification examples can be implemented in combination with each other within a technically consistent range.
In the above embodiment, the connecting pin 150 is pushed by the swing plates 130 and 450 and arranged between the inner arm 90 and the outer arm 100 so that the state of the intake side rocker arm 70 is switched. The mode of switching the state of the intake side rocker arm 70 is not limited to this. For example, the configuration shown in FIG. 19 can be adopted.

As shown in FIG. 19, the intake side rocker arm 470 has an outer arm 480 and an inner arm 490 provided so as to be tiltable with respect to the outer arm 480. The outer arm 480 has a support end portion 481 in which an adjuster hole portion 481A through which the plunger 62 of the lash adjuster 60 is inserted is formed. Further, the outer arm 480 has a swing end portion 482 in which a valve hole 482A through which the upper end portion of the intake valve 24 is inserted is formed. A support wall 483 is provided at the swing end portion 482. A pin hole 483A is formed in the support wall 483. The support end portion 481 and the swing end portion 482 are connected by an outer side wall 484. A support hole 484A is formed at the upper end of the outer side wall 484. In the outer arm 480, the support end portion 481 is supported by the lash adjuster 60, and the swing end portion 482 is supported by the intake valve 24.

The inner arm 490 has an inner side wall 491. A connecting hole 491A is formed in the inner side wall 491. The connecting hole 491A is arranged coaxially with the support hole 484A of the outer side wall 484. A tilting shaft 492 is inserted through the support hole 484A and the connecting hole 491A. The tilting shaft 492 is rotatably supported with respect to the support hole 484A and is connected to the connecting hole 491A. Therefore, the tilting shaft 492 and the inner side wall 491 are integrally rotatable with respect to the outer arm 480. A roller shaft 493 is inserted through the inner arm 490. A roller 495 is rotatably supported on the roller shaft 493 via a ball bearing 494. The intake cam 41 of the intake camshaft 40 comes into contact with the outer peripheral surface of the roller 495. The inner arm 490 is provided with a transmission wall portion 496 protruding from the inner side wall 491. The transmission wall portion 496 is arranged at a position facing the swing end portion 482 of the outer arm 480.

The connecting pin 500 is inserted into the pin hole 483A of the outer arm 480. The connecting pin 500 includes a columnar portion 501 formed in a cylindrical shape and a block portion 502 connected to one end of the columnar portion 501. The cylindrical portion 501 is formed with a flange portion 501A having an enlarged diameter at the central portion in the axial direction thereof. The flange portion 501A is in contact with the side surface of the support wall 483. On the side of the cylindrical portion 501 that is separated from the support wall 483 from the flange portion 501A (on the right side in FIG. 19), a concave insertion portion 501B having a notched upper half peripheral portion is formed. A pressing spring 503 is arranged between the block portion 502 of the connecting pin 500 and the support wall 483 of the outer arm 480. The pressing spring 503 acts to urge the block portion 502 toward the inner arm 490 side (left side in FIG. 19). Therefore, the connecting pin 500 is arranged at a position where the flange portion 501A abuts on the support wall 483 when no other external force is applied. In this state, the block portion 502 is arranged between the swing end portion 482 of the outer arm 480 and the transmission wall portion 496 of the inner arm 490. As a result, the intake side rocker arm 470 is in a locked state in which the relative tilt of the inner arm 490 and the outer arm 480 is restricted. The position of the connecting pin 500 at this time is called the first position. When the inner arm 490 is in the locked state, when the roller 495 is pressed by the intake cam 41, the force acting from the intake cam 41 is transmitted to the outer arm 480 via the inner arm 490. As a result, the outer arm 480 swings around the support point O1 supported by the lash adjuster 60 as shown by an arrow in FIG. 19, and the outer arm 480 swings as shown by a two-dot chain line in FIG. The moving end 482 moves downward. As a result, the intake valve 24 is pushed down.

Further, by moving the connecting pin 500 to the side where the flange portion 501A is separated from the support wall 483 by the switching mechanism 510 described later, the block portion 502 is the swinging end portion 482 of the outer arm 480 and the inner arm 490. It is pulled out from between the transmission wall portion 496 and the transmission wall portion 496. As a result, the inner arm 490 can be tilted with respect to the outer arm 480 about the tilting shaft 492, and the intake side rocker arm 470 is in an unlocked state in which the relative tilting of the inner arm 490 and the outer arm 480 is allowed. It becomes. The position of the connecting pin 500 at this time is called the second position.

As shown by the solid arrow in FIG. 20, in this state, when the roller 495 is pressed by the intake cam 41, the inner arm 490 tilts with respect to the outer arm 480 with the tilting shaft 492 as the support point O2. Therefore, the force acting on the roller 495 from the intake cam 41 acts as a force for tilting the inner arm 490 as shown by the two-dot chain line in FIG. 20, and it is difficult to be transmitted to the outer arm 480. In this configuration, when the intake side rocker arm 470 is in the unlocked state, the outer arm 480 does not swing around the support point O1 supported by the lash adjuster 60.

In this configuration, the state of the intake side rocker arm 470 is switched as follows.
As schematically shown in FIG. 21, the switching mechanism 510 has an operation shaft 520. The operation shaft 520 has a first shaft 521 and a second shaft 522. The configuration of the first shaft 521 is the same as the configuration of the first shaft 121 of the first embodiment, and the configuration of the second shaft 522 is the same as the configuration of the second shaft 122 of the first embodiment. The first swing plate 531 is connected to the first shaft 521, and the second swing plate 532 is connected to the second shaft 522. In the axial view shown in FIG. 21, the first swing plate 531 is arranged at positions where the phases of the second swing plate 532 and the operation shaft 520 in the circumferential direction are different from each other. The motor 140 rotates the operating shaft 520 in the counterclockwise direction indicated by the solid arrow in FIG. The second swing plate 532 is arranged in front of the first swing plate 531 in the rotation direction of the operation shaft 520. When the operation shaft 520 rotates, the torque of the motor 140 first compresses the second torsion spring 124. As a result, in the operation shaft 520, both the first shaft 521 and the second shaft 522 rotate while maintaining a predetermined relative phase. Therefore, when the operation shaft 520 rotates, the second swing plate 532 comes into contact with the insertion portion 501B of the connecting pin 500 of the intake side rocker arm 470 arranged at the position corresponding to the second swing plate 532.

Then, the second swing plate 532 moves the connecting pin 500 of the intake side rocker arm 470 against the urging force of the pressing spring 503, thereby pulling the connecting pin 500 in the direction of the arrow of the alternate long and short dash line in FIG. 21. As a result, the position of the connecting pin 500 is switched from the first position to the second position.

In the switching mechanism 510, the first shaft 521 is rotated by further applying torque by the motor 140 from this state. In this state, the second shaft 522 does not rotate, and the first shaft 521 rotates while compressing both the first torsion spring 123 and the second torsion spring 124. In this way, by rotating the first shaft 521, the first swing plate 531 comes into contact with the connecting pin 500 of the intake side rocker arm 470 arranged at the position corresponding to the first swing plate 531 and the connecting pin. The 500 is moved against the urging force of the pressing spring 503.

As described above, even when the intake side rocker arm 470 whose state can be switched by pulling out the connecting pin 500 from between the inner arm 490 and the outer arm 480 by the swing plate 530 is adopted, the operation of each of the above embodiments is performed. It is possible to apply the same configuration as the valve mechanism.

-In the intake side rocker arms 70 and 470, the connecting pins 150 and 500 are arranged at the other end on the intake valve 24 side, but it is also possible to arrange the connecting pins at one end on the lash adjuster 60 side. In this configuration, for example, the configurations shown in FIGS. 22 and 23 can be adopted.

As shown in FIG. 22, the intake side rocker arm 570 has an outer arm 580 and an inner arm 590 provided so as to be tiltable with respect to the outer arm 580. The outer arm 580 has a support end portion 581 in which an adjuster hole portion 581A through which the plunger 62 of the lash adjuster 60 is inserted is formed. A pin hole 581B through which the connecting pin 600 is inserted is formed in the support end portion 581. The outer arm 580 has a swing end portion 582 in which a valve hole 582A through which the upper end portion of the intake valve 24 is inserted is formed. The support end portion 581 and the swing end portion 582 are connected by an outer side wall 584. A support hole 584A is formed in the outer side wall 584. In the outer arm 580, the support end portion 581 is supported by the lash adjuster 60, and the swing end portion 582 is supported by the intake valve 24.

The inner arm 590 has an inner side wall 591. A connecting hole 591A is formed in the inner side wall 591. The connecting hole 591A is arranged coaxially with the support hole 584A of the outer side wall 584. A tilting shaft 592 is inserted through the support hole 584A and the connecting hole 591A. The tilting shaft 592 is rotatably supported with respect to the support hole 584A and is connected to the connecting hole 591A. Therefore, the tilting shaft 592 and the inner side wall 591 are integrally rotatable with respect to the outer arm 580. A roller shaft 593 is inserted through the inner arm 590. A roller 595 is rotatably supported on the roller shaft 593 via a ball bearing 594. The intake cam 41 of the intake camshaft 40 comes into contact with the outer peripheral surface of the roller 595. The inner arm 590 is provided with an engaging wall portion 596 protruding from the inner side wall 591. The engaging wall portion 596 is formed with an engaging portion 596A facing the opening of the pin hole 581B of the outer arm 580.

The connecting pin 600 is inserted into the pin hole 581B of the outer arm 580. The connecting pin 600 includes a columnar portion 601 formed in a cylindrical shape and an urging portion 602 connected to one end of the columnar portion 601. A pressing spring 603 is arranged between the urging portion 602 of the connecting pin 600 and the outer arm 580. The pressing spring 603 acts to urge the urging portion 602 to a side (left side in FIG. 22) away from the inner arm 590. Therefore, the connecting pin 600 is arranged at a position separated from the engaging portion 596A of the inner arm 590 when no other external force is applied. In this state, the inner arm 590 and the outer arm 580 are in an unlocked state where relative tilting is allowed. The position of the connecting pin 600 at this time is called the second position.

As shown in FIG. 22, in this configuration, by bringing the swing plate 130 of the switching mechanism 110 into contact with the connecting pin 600, the connecting pin 600 is moved against the urging force of the pressing spring 603 to move the inner arm. It engages with the engaging portion 596A of the 590. As a result, the intake side rocker arm 570 is in a locked state in which the relative tilt of the inner arm 590 and the outer arm 580 is restricted. The position of the connecting pin 600 at this time is called the first position. In this way, even if the connecting pin 600 is arranged at one end on the lash adjuster 60 side, the position of the connecting pin 600 can be changed from the second position to the first position by pushing the connecting pin 600 with the swing plate 130. The inner arm 590 and the outer arm 580 can be engaged with each other. Therefore, in the configuration in which the connecting pin 600 is arranged at one end on the lash adjuster 60 side, it is possible to realize a configuration in which the state of the intake side rocker arm 570 is switched between the unlocked state and the locked state.

It is also possible to adopt the configuration shown in FIG. In FIG. 23, the urging direction of the pressing spring is different from the configuration of FIG. 22. The same configurations as those shown in FIGS. 21 and 22 are designated by common reference numerals and the description thereof will be omitted.

As shown in FIG. 23, a support wall 610 is provided at the support end portion 581 of the outer arm 580. A pin hole 610A is formed in the support wall 610. A connecting pin 620 is inserted through the pin hole 610A. The connecting pin 620 is formed in a columnar shape, and a partially enlarged flange portion 620A is formed in a central portion in the axial direction thereof. The flange portion 620A is in contact with the side surface of the support wall 610. In the connecting pin 620, a protrusion 620B is provided on the inner arm 590 side of the support wall 610. On the side of the connecting pin 620 that is separated from the support wall 610 from the flange portion 501A (on the left side in FIG. 23), a concave insertion portion 620C having a notched upper half peripheral portion is formed. A pressing spring 621 is arranged between the protrusion 620B of the connecting pin 620 and the support wall 610 of the outer arm 580. The pressing spring 621 acts to urge the connecting pin 620 to the engaging portion 596A side (right side in FIG. 23) of the inner arm 590. Therefore, the connecting pin 620 is arranged at a position where the flange portion 620A abuts on the support wall 610 and engages with the engaging portion 596A of the inner arm 590 when no other external force is applied. As a result, the intake side rocker arm 670 is in a locked state in which the relative tilt of the inner arm 590 and the outer arm 580 is restricted. The position of the connecting pin 620 at this time is called the first position.

In this configuration, the swing plate 530 of the switching mechanism 510 is brought into contact with the connecting pin 620 to move the connecting pin 620 against the urging force of the pressing spring 621 with the engaging portion 596A of the inner arm 590. Disengage. As a result, the intake side rocker arm 670 is in an unlocked state in which the relative tilt of the inner arm 590 and the outer arm 580 is allowed. The position of the connecting pin 620 at this time is called the second position. In this way, in the configuration in which the connecting pin 620 is arranged at one end on the lash adjuster 60 side, the position of the connecting pin 600 is switched from the first position to the second position by pulling out the connecting pin 620 by the swing plate 530. Can be done. Therefore, it is possible to switch the state of the intake side rocker arm 670 between the unlocked state and the locked state.

-In the above embodiment, when adjusting the output of the motor 140, the current may be controlled instead of the voltage. Further, both voltage and current may be controlled.
-In the first embodiment, an example in which the control duty ratio when controlling the motor 140 is set to three patterns of 0%, 50%, and 100% is shown, but the setting mode of the control duty ratio is not limited to these. .. For example, the control duty ratios when controlling the motor 140 may be set to be non-uniform, such as 0%, 30%, and 100%. In this case, it is desirable to design the spring constant of each torsion spring so that the output torque of the motor 140 is at the center position of the dead zone region, for example, at 30%.

In the above embodiment, the spring constant of each torsion spring is designed so that the output torque at the control duty ratio set when controlling the motor 140 is at the center position of the dead zone region. Instead of such a configuration, the spring constant of each torsion spring may be designed so that the output torque in the control duty ratio set when controlling the motor 140 deviates from the center position in the dead zone region. ..

A dead zone region is provided so that the change in the output torque of the motor 140 is not reflected in the change in the rotation angle of the motor 140, but the dead zone region is not necessarily provided.
The stopper wall portion 30A can be provided in addition to the cam housing 30. For example, it may be provided on the cylinder head 10 or the cam cap 31.

In the first embodiment, the state switching timings of the two intake side rocker arms 70A of the four intake side rocker arms 70 are the same, and the state switching timings of the remaining two intake side rocker arms 70B are the same. Instead of such a configuration, the state switching timings of the three intake side rocker arms 70 out of the four intake side rocker arms 70 are set to be the same, and these switching timings and the state switching timings of the remaining one intake side rocker arm 70 are set. May be different.

-In the second embodiment, one intake side rocker arm 70 is provided for one cylinder 20, but even when a configuration in which a plurality of intake side rocker arms 70 are provided for one cylinder 20, the above is adopted. It is possible to apply the same configuration as in the embodiment. That is, an example in which one swing plate is connected to each split shaft 420 is shown, but in each split shaft 420, as many swing plates as the number of intake side rocker arms 70 provided for one cylinder 20 are shown. It is also possible to adopt a configuration in which the above are connected side by side.

-The number of cylinders in an internal combustion engine is not limited to four. For example, the valve valve mechanism may be applied to an internal combustion engine having three or more cylinders or five or more cylinders.
The valve operating mechanism switching device can be applied not only to the intake side rocker arm 70 but also to the exhaust side rocker arm 170. That is, the valve operating mechanism may not include a switching mechanism for switching the state of the intake side rocker arm 70, but may include only a switching mechanism for switching the state of the exhaust side rocker arm 170. Further, both a switching mechanism for switching the state of the intake side rocker arm 70 and a switching mechanism for switching the state of the exhaust side rocker arm 170 may be provided.

10 ... Cylinder head, 11 ... Intake port, 12 ... Exhaust port, 13 ... First accommodating part, 14 ... Second accommodating part, 15 ... Intermediate part, 16 ... Holding part, 17 ... First communication hole, 18 ... Second Communication hole, 20 ... Cylinder, 21 ... Fuel injection valve, 22 ... 1st valve guide, 23 ... 2nd valve guide, 24 ... Intake valve, 25 ... 1st valve lifter, 26 ... 1st compression spring, 27 ... Exhaust valve, 28 ... 2nd valve lifter, 29 ... 2nd compression spring, 30 ... cam housing, 30A ... stopper wall, 31 ... cam cap, 32 ... cylinder head cover, 33 ... bolt, 40 ... intake cam shaft, 41 ... intake cam, 42 ... Large cam, 42A ... Cam mountain, 43 ... Small cam, 43A ... Cam mountain, 37 ... Exhaust cam shaft, 38 ... Exhaust cam, 60 ... Rush adjuster, 61 ... Adjuster body, 62 ... Plunger, 70, 70A, 70B , 70C, 70D ... Intake side rocker arm, 80 ... Arm part, 90 ... Inner arm, 91 ... Support end part, 91A ... Adjuster hole part, 92 ... Swinging end part, 92A ... Locking surface, 92B ... Valve hole, 93 ... roller holding part, 94 ... inner side wall, 94A ... support hole, 95 ... roller shaft, 96 ... ball bearing, 97 ... roller, 98 ... torsion spring, 100 ... outer arm, 101 ... fulcrum end, 101A ... tilting hole , 102 ... outer side wall, 103 ... tilting end, 104 ... connecting part, 105 ... support wall, 105A ... pin hole, 110 ... switching mechanism, 120 ... operation shaft, 121 ... first shaft, 121A ... first support piece, 121B ... 2nd support piece, 122 ... 2nd shaft, 122A ... Insertion hole, 122B ... 3rd support piece, 123 ... 1st torsion spring, 123A ... 11th fixed end, 123B ... 1st coil part, 123C ... 12th Fixed end, 124 ... 2nd torsion spring, 124A ... 21st fixed end, 124B ... 2nd coil part, 124C ... 22nd fixed end, 130 ... swing plate, 131 ... first swing plate, 132 ... second swing Dynamic plate, 140 ... motor, 140A ... drive shaft, 150 ... connecting pin, 151 ... locking part, 152 ... flange part, 153 ... urging part, 160 ... pressing spring, 170 ... exhaust side rocker arm, 200 ... internal combustion engine, 300 ... valve mechanism, 400 ... switching mechanism, 410 ... operation shaft, 420 ... split shaft, 425 ... center shaft, 425A ... first support piece, 425B ... second support piece, 430 ... outer shaft, 431 ... first outer Shaft, 431A ... 1st insertion hole, 431B ... 3rd support piece, 431C ... 4th support piece, 432 ... 2nd outer shaft, 432A ... 2nd insertion hole, 432B ... 5th support piece, 432C ... 6th support piece, 433 ... 3rd outer shaft, 433A ... 3rd insertion hole, 433B ... 7th support piece, 440 ... 1st torsion spring, 440A ... 11th fixed end, 440B ... 1st coil portion, 440C ... 12th fixed end, 441 ... 2nd torsion spring, 441A ... 21st fixed end, 441B ... 2 coil part, 441C ... 22nd fixed end, 442 ... 3rd torsion spring, 442A ... 31st fixed end, 442B ... 3rd coil part, 442C ... 32nd fixed end, 443 ... 4th torsion spring, 443A ... 41st Fixed end, 443B ... 4th coil portion, 443C ... 42nd fixed end, 450 ... swing plate, 451 ... first swing plate, 452 ... second swing plate, 453 ... third swing plate, 454 ... 4 swing plate, 470 ... intake side rocker arm, 480 ... outer arm, 481 ... support end, 481A ... adjuster hole, 482 ... swing end, 482A ... valve hole, 483 ... support wall, 483A ... pin hole, 484 ... outer side wall, 484A ... support hole, 490 ... inner arm, 491 ... inner side wall, 491A ... connecting hole, 492 ... tilting shaft, 493 ... roller shaft, 494 ... ball bearing, 495 ... roller, 494 ... transmission wall, 500 ... Connecting pin, 501 ... Cylindrical part, 501A ... Flange part, 501B ... Insertion part, 502 ... Block part, 503 ... Pressing spring, 510 ... Switching mechanism, 520 ... Operation shaft, 521 ... First shaft, 522 ... Second Shaft, 523 ... 1st torsion spring, 524 ... 2nd torsion spring, 530 ... swing plate, 513 ... 1st swing plate, 532 ... second swing plate, 570 ... intake side rocker arm, 580 ... outer arm, 581 ... Support end, 581A ... Adjuster hole, 581B ... Pin hole, 582 ... Swinging end, 582A ... Valve hole, 584 ... Outer side wall, 584A ... Support hole, 590 ... Inner arm, 591 ... Inner side wall, 591A ... Connecting hole, 592 ... Tilt shaft, 593 ... Roller shaft, 594 ... Ball bearing, 595 ... Roller, 596 ... Engaging wall part, 596A ... Engaging part, 600 ... Connecting pin, 601 ... Column part, 602 ... Biasing part , 603 ... Pressing spring, 610 ... Support wall, 610A ... Pin hole, 620 ... Connecting pin, 620A ... Flange part, 620B ... Protruding part, 620C ... Insertion part, 621 ... Pressing spring.

Claims (3)

With the camshaft,
With the cam connected to the camshaft,
One end is supported by a lash adjuster and the other end is supported by an engine valve, and by being pressed by the cam, a movement provided with a plurality of rocker arms that swing the other end around the one end. It ’s a valve mechanism,
The rocker arm
An inner arm, an outer arm provided so as to be tiltable relative to the inner arm, a locked state in which the relative tilt between the inner arm and the outer arm is restricted, and the inner arm and the outer arm. It has a switching mechanism that can switch to an unlocked state where relative tilting is allowed.
The switching mechanism is
An operation shaft extending in the same direction as the axis of the camshaft,
A swing plate connected to the operation shaft and arranged side by side at a position corresponding to the rocker arm.
The actuator that rotates the operation shaft and
It has connecting pins arranged side by side at positions corresponding to the swing plate.
The connecting pin can be switched between a first position in which the state of the inner arm and the outer arm is in the locked state and a second position in which the state of the outer arm is in the unlocked state.
The swing plate is formed by the actuator rotating the operation shaft for either the switching from the first position to the second position or the switching from the second position to the first position. A valve operating mechanism that switches the position of the connecting pin by bringing it into contact with the connecting pin. The operation shaft includes a first shaft with which the actuator abuts, a second shaft coaxially arranged with the first shaft and having an insertion hole through which the first shaft is inserted, and the first shaft having the first shaft. It has an elastic member that is connected to the first shaft and the second shaft in a state of being inserted through the second shaft and allows relative rotation between the first shaft and the second shaft.
The valve operating mechanism according to claim 1, wherein the swing plate includes a first swing plate connected to the first shaft and a second swing plate connected to the second shaft. The operation shaft has a plurality of split shafts having the same number of cylinders as the number of cylinders of an internal combustion engine, and an elastic member for connecting the split shafts to each other.
Each of the divided shafts is coaxially arranged, and has a central shaft which is arranged on the innermost side of the plurality of divided shafts and with which the actuator abuts, and an insertion hole through which the central shaft is inserted. Including a plurality of outer shafts arranged so as to overlap each other on the outer peripheral side of the central shaft.
The elastic member has the inner peripheral side in a state where the inner peripheral side shaft arranged on the inner peripheral side of the divided shaft is inserted into the outer peripheral side shaft arranged on the outer peripheral side of the inner peripheral side shaft. Allows relative rotation between the shaft and the outer peripheral side shaft,
The valve operating mechanism according to claim 1, wherein the swing plate is connected to each of the plurality of split shafts.

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