JP2012002090A - Variable valve system of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To switch valve lift characteristics to three stages with high responsiveness, in a simple structure.SOLUTION: A position of a pin line 700 to be inserted into three roller rocker arms 61, 62, and 63 is changed, to disconnect or connect the roller rocker arms adjacent to each other. A first spiral-groove formed body 111 and a second spiral-groove formed body 121 are provided on a camshaft 30. A second actuator 102 is driven, and an inserting/removing pin 9a is inserted to a second spiral groove 122, to move a second slide-swing arm 92 to a third position, during a low- and middle-load operation. In a fuel-cut operation, a first actuator 101 is driven, and the inserting/removing pin 9a is inserted to a first spiral groove 112, to move a first slide-swing arm 91 to a second position.

Description

  The present invention relates to a variable valve operating apparatus for an internal combustion engine that switches a valve lift characteristic of the internal combustion engine in three stages.

  2. Description of the Related Art Conventionally, variable valve gears that switch a valve lift amount in three stages according to the operating state of an internal combustion engine are known. Such a variable valve operating device is proposed in Patent Document 1, for example. The variable valve apparatus proposed in Patent Document 1 includes a switching device that disconnects or connects three rocker arms supported by a rocker shaft to each other and switches the lift amount of the valve in three stages. The switching device is driven by a cylindrical first switching pin that detachably connects the first rocker arm and the second rocker arm, and a piston housed in a through hole of the first switching pin, and the second rocker arm and the second rocker arm. (3) A second switching pin for detachably connecting the rocker arm, a first spring for urging the first switching pin to the detaching position, and a urging force more than the first spring for urging the second switching pin to the detaching position. A large second spring, a first switching pin, and an oil chamber for applying hydraulic pressure to the piston are provided. In this variable valve operating apparatus, an oil passage is formed in the rocker shaft, and two switching pins are selectively driven by controlling the magnitude of the hydraulic pressure supplied to the oil chamber via the oil passage.

JP 2006-299916 A

  However, since the switching pin is driven by hydraulic pressure, a hydraulic circuit is required, resulting in a large system configuration. In addition, when the switching pin is driven by hydraulic pressure, the switching timing is delayed because of poor response.

  An object of the present invention is to address the above-described problems, and an object of the present invention is to switch the valve lift characteristics to three stages with a simple configuration and high response.

  In order to achieve the above object, the present invention is characterized in that in the variable valve operating apparatus for an internal combustion engine, any one of three cams having different cam profiles can be selected as a valve drive cam. , 32, 33) are transmitted to each of the three rocker arms (61, 62, 63) to swing according to each cam profile, and a plurality of pins (71 , 72, 73, 74, 75, 76) are inserted through a pin array (700) arranged in series, and the adjacent rocker arms are separated from each other depending on the insertion position of the pin array; A connection state switching mechanism (650) that selectively transmits the operating force of any one of the three cams to the valve, and a rotating body that rotates integrally with the camshaft (30). The first spiral groove (112, 171) formed in a spiral shape and a spiral formed on a rotating body that rotates integrally with the camshaft, the axial distance of the camshaft is longer than the first spiral groove. An insertion / removal pin (9a) is selectively inserted into the second spiral groove (122, 172), the first spiral groove and the second spiral groove, and the insertion / removal pin is spiraled by rotation of the camshaft. A pin drive mechanism (200, 210) that changes the insertion position of the pin row in two ways with respect to a reference position by transmitting a force pushed by the groove to the pin row of the connection state switching mechanism; It is in.

  In the present invention, three rocker arms and a connection state switching mechanism are provided. The connected state switching mechanism switches between a state where adjacent rocker arms are separated from each other and a connected state. Therefore, when the three rocker arms are separated from each other, the operating force of each cam is transmitted to the rocker arm, and the three rocker arms perform a swinging motion according to the cam profile of each cam.

  The connection state switching mechanism inserts a pin row in which a plurality of pins are arranged in series into three rocker arms, and switches between a state in which adjacent rocker arms are separated from each other and a state in which they are connected depending on the insertion position of the pin row. . That is, adjacent rocker arms are connected when the pins constituting the pin row are inserted across the two rocker arms, and conversely when adjacent pins are not inserted across the two rocker arms. The arms are separated from each other. Therefore, the lift characteristics (lift amount and working angle) of the valve connected to the specific rocker arm are varied according to the connection state of the rocker arm.

  In the present invention, in order to change the insertion position of the pin row, a first spiral groove, a second spiral groove, and a pin drive mechanism are provided. The first spiral groove and the second spiral groove are formed in a rotating body that rotates integrally with the camshaft. For example, a cylindrical body may be used as the rotating body. Further, the first spiral groove and the second spiral groove may be formed in separate rotating bodies or may be formed in one rotating body. The two spiral grooves are formed in a spiral shape around the central axis of the camshaft, and the axial distance of the camshaft is longer in the second spiral groove than in the first spiral groove.

  The pin drive mechanism includes an insertion / removal pin that can be inserted into and removed from the first spiral groove and the second spiral groove, and the insertion / removal pin is selectively inserted into the first spiral groove and the second spiral groove. To do. The insertion / removal pin is provided so as not to move in the circumferential direction of the camshaft but to move in the axial direction. Therefore, the insertion / removal pin is pushed by the wall surface of the spiral groove (first spiral groove or second spiral groove) by the rotation of the camshaft and moves in the axial direction of the camshaft. The force with which the insertion / removal pin is pushed is transmitted to the pin row of the connection state switching mechanism. Therefore, the pin row moves by the distance that the insertion / removal pin has moved in the axial direction of the camshaft. Thereby, the insertion position of the pin row in the three rocker arms changes with respect to the reference position. The reference position is a position where the pin row is not pressed.

  The first spiral groove and the second spiral groove are different in the axial distance of the camshaft. Therefore, by selecting the spiral groove into which the insertion / removal pin is inserted, the insertion position of the pin row in the three rocker arms can be changed in two ways with respect to the reference position. For this reason, the insertion position of the pin row can be set to a total of three positions including the reference position.

  Thereby, the connection state in the connection state switching mechanism can be switched in three ways, and the operating force of any one of the three cams can be selectively transmitted to the valve. For example, in the reference position, the specific rocker arm connected to the valve swings according to the cam profile of the first cam. In the second position where the insertion / removal pin is pushed by the first spiral groove and the insertion position of the pin row is moved, the specific rocker arm swings according to the cam profile of the second cam. Further, at the third position where the insertion / removal pin is pushed by the second spiral groove and the insertion position of the pin row is moved, the specific rocker arm can be swung according to the cam profile of the third cam. Therefore, the valve lift characteristic can be switched in three stages.

  As described above, according to the present invention, the valve lift characteristic is switched to three stages by selectively inserting the insertion / removal pins into the two spiral grooves, so that a simple configuration without requiring a large-scale configuration such as a hydraulic circuit is required. In addition, good responsiveness can be obtained.

  In addition, it is preferable to provide the connection state switching mechanism with a return spring that urges the pin row in a direction opposite to the direction in which the pin row is pushed by the pin drive mechanism. In this case, the insertion position of the pin row can be properly maintained and the pin row can be automatically returned to the reference position.

  Another feature of the present invention is that the first spiral groove and the second spiral groove have two spiral grooves having different depths in a rotating body (160) that rotates integrally with the camshaft. ) Are arranged in common, and the shallower spiral groove is defined as the first spiral groove (171), and the deeper spiral groove is defined as the second spiral groove (172). The pin drive mechanism (210) is provided with an actuator (103) that allows the insertion / removal pin to be inserted into the spiral two-step groove and the insertion amount to be switched between two steps.

  In the present invention, a spiral two-stage groove is formed in one rotating body that rotates integrally with the camshaft, and an insertion / removal pin is inserted into the spiral two-stage groove with an insertion amount selected by an actuator. . The spiral two-step groove is formed by arranging two spiral grooves having different depths by forming the bottom surface of the spiral groove in a step shape with the common start end (starting portion of the groove). Functionally, the spiral groove only needs to have a vertical wall surface extending spirally in order to push the insertion / removal pin. Therefore, by forming the bottom surface of the spiral groove in a step shape, the vertical wall surface extending in a spiral shape can be formed in two upper and lower steps. In the deeper groove, the axial distance of the camshaft can be set longer than in the shallower groove. Therefore, the shallower spiral groove is the first spiral groove, and the deeper spiral groove is the second spiral groove.

  The actuator is configured such that the insertion amount of the insertion / removal pin can be switched between two stages. Therefore, by setting the insertion amount according to the depth of the two spiral grooves, the insertion groove is selected to select the spiral groove into which the insertion / removal pin is inserted (the spiral groove where the insertion / removal pin is pushed). be able to. In this case, the insertion / removal pin is guided along the spiral groove corresponding to the insertion amount by being dropped at the start end of the spiral double step groove or in front of it.

  Thus, according to the present invention, the connection state in the connection state switching mechanism can be set in three ways by providing only one rotating body, actuator, and insertion / removal pin each having a spiral two-step groove. The score can be reduced.

  Another feature of the present invention is that the pin driving mechanism (210) is supported by a rocker shaft that supports the rocker arm so that the rocker arm can swing, and is capable of moving in an axial direction, and the insertion / removal pin is provided at a distal end side. The slide swing arm (93) provided, the actuator (103) that swings the slide swing arm and can be switched between two swing angles, and the actuator is driven to control the slide swing arm. The movable arm is swung by a first swing angle, the insertion / removal pin is inserted into the first spiral groove (171), and the slide swing arm is moved to a second swing angle larger than the first swing angle. Actuator driving means (150) for swinging the insertion / removal pin into the second spiral groove (172) and pushing the insertion / removal pin into one spiral groove of the spiral two-step groove. It said slide swing arm biases the pin rows with a force which moves the rocker shaft in the axial direction is, there insertion position of the pin rows to be changed by the moving distance of the slide oscillating arm.

  In the present invention, the slide rocking arm is rocked by driving the actuator, and the insertion / removal pin provided on the tip side of the slide rocking arm is inserted into the spiral two-step groove. The slide swing arm is supported by the rocker shaft so as to be swingable and axially movable. The rocker shaft supports the rocker arm so as to be swingable. The actuator can be switched between two swing angles when swinging the slide swing arm. For example, when an actuator that swings the slide rocking arm by pushing the rear end of the slide rocking arm is used, the stroke (projection amount) of the movable shaft that pushes the rear end of the slide rocking arm is switched between two ways. Thus, the swing angle can be switched between two ways.

  The magnitude of the swing angle corresponds to the amount of insertion of the insertion / removal pin provided on the distal end side of the slide swing arm into the spiral two-step groove. In this case, when the slide swing arm swings by the first swing angle, the insertion / removal pin is inserted into the first spiral groove, and the slide swing arm swings by the second swing angle (> first swing angle). Then, the insertion / removal pin is set to be inserted into the second spiral groove.

  The actuator is driven and controlled by actuator driving means. The actuator driving means swings the slide swing arm by the first swing angle to insert the insertion / removal pin into the first spiral groove. Further, the slide swing arm is swung by the second swing angle, and the insertion / removal pin is inserted into the second spiral groove. Therefore, the spiral groove (first spiral groove or second spiral groove) into which the insertion / removal pin is inserted can be selected by switching the swing angle of the slide swing arm.

  When the insertion / removal pin is inserted into the spiral groove and pushed by the spiral groove, the slide rocking arm moves in the axial direction while being supported by the rocker shaft together with the insertion / removal pin. The pin row is biased by the moving force of the slide swing arm. In this case, for example, the end of the pin row may be pushed on the side surface of the slide swing arm. Thereby, the insertion position of the pin row in the three rocker arms changes by the moving distance of the slide rocking arm.

  Therefore, according to the present invention, the connection state in the connection state switching mechanism can be set in three ways by switching the swing angle at which the slide swing arm is swung by the actuator. In addition, since the pin row is moved by using the operation (movement along the rocker shaft) of the slide swing arm for inserting the insertion / removal pin into the spiral groove, it can be implemented with a very simple configuration. .

  In the above description, in order to help the understanding of the invention, the reference numerals used in the embodiments are attached to the configuration of the invention corresponding to the embodiments in parentheses. It is not intended to be limited to the embodiment defined by.

FIG. 1 is a schematic configuration diagram of an internal combustion engine in the embodiment. FIG. 2 is a schematic configuration diagram illustrating a relationship among the variable mechanism, the cam, and the intake valve. FIG. 3 is a schematic configuration diagram illustrating a relationship between the connection state switching mechanism and the pin driving mechanism. FIG. 4 is a cross-sectional view illustrating a state of the connection state switching mechanism in the first position. FIG. 5 is a cross-sectional view illustrating a state of the connection state switching mechanism in the second position. FIG. 6 is a cross-sectional view illustrating the state of the connection state switching mechanism at the third position. FIG. 7 is a side view of the first roller rocker arm and the first cam. FIG. 8 is a side view of the second roller rocker arm and the second cam. FIG. 9 is a side view of the third roller rocker arm and the third cam. FIG. 10 is an explanatory diagram of the operation of the slide swing arm. FIG. 11 is an explanatory diagram of the operation of the slide swing arm. FIG. 12 is a cross-sectional view illustrating a connection structure of the slide arm and the slide swing arm to the rocker shaft. FIG. 13 is an explanatory view showing the relationship between the fixed pin and the opening in the connecting structure of the slide swing arm. FIG. 14 is an explanatory diagram illustrating the relationship between the fixing pin and the opening in the slide arm connection structure. FIG. 15 is a sectional view showing the shaft return mechanism. FIG. 16 is a graph showing valve lift timing. FIG. 17 is a front view of the pressing piece for explaining the positional relationship between the movable shaft of the actuator and the recess of the pressing piece. 18 is a cross-sectional view (XX cross-sectional view of FIG. 17) of the pressing piece for explaining the positional relationship between the movable shaft of the actuator and the concave portion of the pressing piece. FIG. 19 is a plan view illustrating a combined delay mechanism. 20 is a cross-sectional view (XX cross-sectional view of FIG. 19) showing the combined delay mechanism. FIG. 21 is a schematic configuration diagram illustrating a relationship between the connection state switching mechanism and the pin driving mechanism in the second embodiment. FIG. 22 is an explanatory diagram of the operation of the slide rocking arm in the second embodiment. FIG. 23 is an explanatory diagram of the operation of the slide rocking arm in the second embodiment. FIG. 24 is an explanatory diagram of the operation of the slide rocking arm in the second embodiment. FIG. 25 is an explanatory diagram of an actuator that has two levels of protrusion in the second embodiment. FIG. 26 is an explanatory diagram of another actuator that has two levels of protrusion in the second embodiment. FIG. 27 is a front view of a spiral groove forming body in the second embodiment. FIG. 28 is a development view of the spiral groove forming body in the second embodiment. FIG. 29 is a front view of the pressing piece for explaining the positional relationship between the movable shaft of the actuator and the two-step concave portion of the pressing piece in the second embodiment. FIG. 30 is a cross-sectional view (XX cross-sectional view of FIG. 29) of the pressing piece for explaining the positional relationship between the movable shaft of the actuator and the two-step concave portion of the pressing piece in the second embodiment.

  Hereinafter, a variable valve operating apparatus for an internal combustion engine according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic configuration of an internal combustion engine to which a variable valve device as an embodiment is applied.

  The internal combustion engine 10 is a 4-stroke cycle spark ignition internal combustion engine. The internal combustion engine 10 includes four cylinders 11, 12, 13, and 14. Each of the cylinders 11, 12, 13, and 14 is provided with two intake valves 20, two exhaust valves 21, and a spark plug 22 that generates a spark.

  As shown in FIG. 2, the intake valve 20 is opened and closed using the operating force of any one of the three cams 31, 32, 33 attached to the intake camshaft 30 and the urging force of the valve spring 25. The The intake camshaft 30 is connected to a crankshaft (not shown) by a timing chain or a timing belt, and is rotated at a speed half that of the crankshaft. Hereinafter, the intake camshaft 30 is simply referred to as a camshaft 30.

  The camshaft 30 is formed with a first cam 31, a second cam 32, and a third cam 33 per cylinder. The first cam 31 has a shape having a cam profile suitable for high load operation. The second cam 32 is provided between the first cam 31 and the third cam 33, and has a cam profile in which the lift amount of the intake valve 20 is substantially zero, that is, a shape having only a base circle (cam nose The height is zero). The third cam 33 has a shape having a cam profile for an Atkinson cycle suitable for low / medium load operation.

  Each cylinder 11, 12, 13, 14 has 1 of the operating force of the first to third cams 31, 32, 33 between the first to third cams 31, 32, 33 and the intake valve 20, respectively. Variable mechanisms 41, 42, 43, 44 for selectively transmitting one to the intake valve 20 are interposed. Hereinafter, the variable mechanism 41 provided in the first cylinder 11 is referred to as a first variable mechanism 41, the variable mechanism 42 provided in the second cylinder 12 is referred to as a second variable mechanism 42, and the variable mechanism 43 provided in the third cylinder 13. Is called the third variable mechanism 43, the variable mechanism 44 provided in the fourth cylinder 14 is called the fourth variable mechanism 44, and when these are collectively referred to without distinction, they are simply called the variable mechanism 40. FIG. 2 shows the relationship between the variable mechanism 40, the cams 31, 32, and 33 and the intake valve 20, and the description of a later-described configuration such as a drive unit that drives the variable mechanism 40 is omitted. .

  The variable mechanism 40 transmits the operating force of the first cam 31 to the intake valve 20, the state of transmitting the operating force of the second cam 32 to the intake valve 20, and the operating force of the third cam 33 to the intake valve 20. By switching between the three states to be transmitted to, the lift characteristic (opening characteristic) of the intake valve 20 is changed in three stages. In the present embodiment, the second cam 32 is a zero lift cam. For this reason, the state where the operating force of the second cam 32 is transmitted to the intake valve 20 means a state where the intake valve 20 does not open and close (valve inactive state).

  As shown in FIG. 3, each variable mechanism 40 includes a common rocker shaft 50. The rocker shaft 50 is a hollow cylindrical tube provided in parallel with the camshaft 30, and is supported by the cylinder head of the internal combustion engine 10 between both ends and the four variable mechanisms 40. Further, a first link shaft 51 and a second link shaft 52 are inserted into the hollow cylinder of the rocker shaft 50 so as to be slidable in the axial direction.

  As shown in FIGS. 3 and 4, each variable mechanism 40 includes a first roller rocker arm 61, a second roller rocker arm 62, and a third roller rocker arm 63 that are swingably supported by the rocker shaft 50. ing. Each roller rocker arm 61, 62, 63 is provided extending in the radial direction from the rocker shaft 50. Hereinafter, when it is not necessary to distinguish the three roller rocker arms 61, 62, 63, they are simply referred to as a roller rocker arm 6.

  A first roller 611 is pivotally supported on the first roller rocker arm 61. The first roller rocker arm 61 is provided at a position where the first roller 611 faces the first cam 31 in the axial direction of the rocker shaft 50. The first roller rocker arm 61 is biased by a spring (not shown) so that the first roller 611 contacts the first cam 31. Accordingly, as shown in FIG. 7, the first roller rocker arm 61 swings according to the cam profile of the first cam 31 with the rocker shaft 50 as the center of rotation.

  The second roller rocker arm 62 is formed in a U shape so as to surround the first roller rocker arm 61 in three directions, and is swingably supported by the rocker shaft 50 on both sides of the first roller rocker arm 61. . One of the arms provided in parallel with each other on both sides of the first roller rocker arm 61 is called a main arm 62a, and the other is called a sub arm 62b. A portion connecting the tip of the main arm 62a and the tip of the sub arm 62b is referred to as a connecting portion 62c. The proximal end portions of the two intake valves 20 are connected to the distal end portion of the second roller rocker arm 62.

  A second roller 621 is pivotally supported on the main arm 62a. The second roller rocker arm 62 is provided at a position where the second roller 621 faces the second cam 32 in the axial direction of the rocker shaft 50. The outer diameter of the second roller 621 is the same as the outer diameter of the first roller 611. Accordingly, the second roller rocker arm 62 is not connected to the first roller rocker arm 61 or the third roller rocker arm 63, as shown in FIG. , The rocker shaft 50 is pivoted according to the cam profile of the second cam 32 around the rotation center. In this case, since the second cam 32 is a zero lift cam, the swing angle is zero. Since the two intake valves 20 are connected to the tip of the second roller rocker arm 62, they are maintained in a valve rest state.

  The third roller rocker arm 63 is disposed next to the main arm 62 a of the second roller rocker arm 62. A third roller 631 is pivotally supported on the third roller rocker arm 63. The third roller rocker arm 63 is provided at a position where the third roller 631 faces the third cam 32 in the axial direction of the rocker shaft 50. The outer diameter of the third roller 631 is the same as the outer diameter of the first roller 611 and the second roller 621. The third roller rocker arm 63 is biased by a spring (not shown) so that the third roller 631 contacts the third cam 33. Therefore, as shown in FIG. 9, the third roller rocker arm 63 swings according to the cam profile of the third cam 33 with the rocker shaft 50 as the rotation center.

  As will be described later, the intake valve 20 is lifted in a state where the first roller rocker arm 61 or the third roller rocker arm 63 is connected to the second roller rocker arm 62. Therefore, the second roller rocker arm 62 has the rocker shaft 50 as the center of rotation by the cooperation of the operating force (swinging force) of the first roller rocker arm 61 or the third roller rocker arm 63 and the biasing force of the valve spring 25. Rocks.

  The positions of the first roller 611, the second roller 621, and the third roller 631 are such that the first roller 611 is in contact with the base circle of the first cam 31 and the second roller 621 is the base of the second cam 32. When the third roller 631 is in contact with the circle and the third roller 631 is in contact with the base circle of the third cam 33, the axis of the first roller 611, the axis of the second roller 621, and the axis of the third roller 631 It is determined that the mind is located on the same straight line.

  Next, in the variable mechanism 40, a connection state switching mechanism 650 that switches the connection state / disconnection state between the second roller rocker arm 62 that lifts the intake valve 20, the first roller rocker arm 61, and the third roller rocker arm 63. This will be described with reference to FIGS.

  A first pin hole 613 is formed in the support shaft 612 of the first roller 611 along the axial direction. One end of the first pin hole 613 opens toward the side surface of the main arm 62 a of the second roller rocker arm 62. Further, the other end of the first pin hole 613 is open toward the side surface of the sub arm 62 b of the second roller rocker arm 62.

  A second main pin hole 623 is formed in the support shaft 622 of the second roller 621 along the axial direction. One end of the second main pin hole 623 opens toward the side surface of the third roller rocker arm 63. Further, the other end of the second main pin hole 623 opens toward the side surface of the first roller rocker arm 61. Further, a second sub pin hole 624 is formed in the sub arm 62 b of the second roller rocker arm 62 at a position on the extension line of the second main pin hole 623. One end of the second sub pin hole 624 opens toward the side surface of the first roller rocker arm 61. The other end of the second auxiliary pin hole 624 opens toward the slide arms 81 and 82 or the slide swing arms 91 and 92 described later.

  A third pin hole 633 is formed in the support shaft 632 of the third roller 631. One end of the third pin hole 633 opens toward the side surface of the second roller rocker arm 62. The other end of the third pin hole 633 is closed. This closed portion is referred to as a closed cylindrical end 634.

  Each pin hole 613, 623, 624, 633 is formed with the same inner diameter. The relative positions of the pin holes 613, 623, 624, and 633 are such that the first roller 611 contacts the base circle of the first cam 31 and the second roller 621 is in contact with the base circle of the second cam 32. The shaft centers of the four pin holes 613, 623, 624, and 633 are set to be on the same straight line when the third roller 631 is in contact with the base circle of the third cam 33. ing. Hereinafter, the row of the four pin holes 613, 623, 624, 633 is referred to as a pin hole row 600.

  The pin hole row 600 includes a pin return spring 77, a spring force transmission member 78, a first pin 71, a second pin 72, and a third pin 73 in order from the third pin hole 633 side to the second sub pin hole 624. The fourth pin 74, the fifth pin 75, and the sixth pin 76 are inserted in series. One end of the pin return spring 77 contacts the closed cylindrical end 634 of the third pin hole 633, and the other end contacts the spring force transmission member 78. The spring force transmitting member 78 is a cylindrical body closed on one side, receives the pressing force of the pin return spring 77 at the closing portion, and transmits the pressing force to the first pin 71. The spring force transmission member 78 is formed so that the outer diameter is equal to the inner diameter of the third pin hole 633, and is inserted into the third pin hole 633 so as to be slidable in the axial direction.

  The first pin 71, the second pin 72, the third pin 73, the fourth pin 74, the fifth pin 75, and the sixth pin 76 are formed in a cylindrical shape so that the outer diameter is equal to the inner diameter of the pin hole row 600. Thus, it is slidable in the axial direction with respect to any of the pin holes 613, 623, 624, 633. Each of the pins 71 to 76 is in a line shape with the adjacent pins in contact with the end surfaces. Hereinafter, the row of six pins 71 to 76 is referred to as a pin row 700. The pin row 700 is arranged on the same straight line when the axial centers of the four pin holes 613, 623, 624, 633 are located on the same straight line.

  The pin row 700 is biased toward the slide arms 81 and 82 or the slide swing arms 91 and 92 described later by the pressing force of the pin return spring 77, and the spring force transmission member 78 and the slide arms 81, 82 or the slide rocking arms 91 and 92. Therefore, the axial position of the pin array 700 (the relative position in the axial direction with respect to the roller rocker arms 61 to 63) changes according to the axial position of the slide arms 81 and 82 or the slide swing arms 91 and 92. It is configured. As a result, the three roller rocker arms 61, 62, and 63 are switched between a state in which adjacent roller rocker arms 61 to 63 are connected and a state in which the roller rocker arms 61 to 63 are disconnected in accordance with the axial position of the pin row 700. The pins 71 to 76 are always arranged between adjacent pins and end faces even when the pin holes 613, 623, 624, and 633 are not on the same straight line due to the swing of the roller rocker arms 61 to 63. The outer diameter (= the inner diameter of the pin hole) is set so as to allow contact.

  The position of the first pin 71 is switched between a position inserted into the second main pin hole 623 and a position inserted into the third pin hole 633 by a pin driving mechanism 200 described later. The axial dimension of the first pin 71 is set to be shorter than the width of the main arm 62 a of the second roller rocker arm 62 (the axial length of the second main pin hole 623). Here, the width of the main arm 62a is the width of the main arm 62a, the gap between the adjacent third roller rocker arm 63 and the gap between the adjacent first roller rocker arm 61. It is a value obtained by adding 1/2 of the above.

  The position of the second pin 72 includes a position where it is inserted across the second main pin hole 623 and the first pin hole 613 and a position where it is inserted into the second main pin hole 623 by the pin driving mechanism 200 described later. The position is changed over to the position where the third pin hole 633 and the second main pin hole 623 are inserted. The axial dimension of the second pin 72 is set to be equal to the width of the main arm 62 a of the second roller rocker arm 62.

  The position of the third pin 73 is switched between a position to be inserted into the first pin hole 613 and a position to be inserted into the second main pin hole 623 by a pin driving mechanism 200 described later. The axial dimension of the third pin 73 is set shorter than the width of the first roller rocker arm 61 (the axial length of the first pin hole 613). Here, the width of the first roller rocker arm 61 refers to the width of the first roller rocker arm 61, the gap between the adjacent main arm 62a and the gap between the adjacent sub arm 62b. It is a value obtained by adding 1/2 of the above.

  The position of the fourth pin 74 is switched between a position inserted into the second sub pin hole 624 and a position inserted into the first pin hole 613 by a pin driving mechanism 200 described later. The axial dimension of the fourth pin 74 is set shorter than the width of the first roller rocker arm 61. The axial dimension connecting the fourth pin 74 and the third pin 73 is set to be equal to the width of the first roller rocker arm 61.

  The position of the fifth pin 75 is switched between a position inserted into the second sub pin hole 624 and a position inserted into the first pin hole 613 by a pin driving mechanism 200 described later. The axial dimension of the fifth pin 75 is set to be shorter than the width of the first roller rocker arm 61. The axial dimension connecting the fifth pin 75 and the fourth pin 74 is set to be equal to the width of the first roller rocker arm 61.

  The position of the sixth pin 76 is switched only in the second auxiliary pin hole 624 by the pin driving mechanism 200 described later, and does not move across the adjacent pin hole 613. The axial dimension of the sixth pin 76 is set to be equal to or longer than the width of the auxiliary arm 62b (the axial length of the second auxiliary pin hole 624).

  As described above, in the variable mechanism 40, the roller rocker arms 61, 62, and 63 are connected to each other by changing the relative position of the pin row 700 with respect to the three roller rocker arms 61, 62, and 63. You can switch between states. Accordingly, the connection state switching mechanism 650 includes the pins 71 to 76 constituting the pin row 700, the pin return spring 77, the spring force transmission member 78, and the pin holes 613, 623, 624 constituting the pin hole row 600. 633. 4 to 6 show the connection state switching mechanism 650 in the first variable mechanism 41, the connection state switching mechanism 650 in the other variable mechanisms 42, 43, 44 is also in the first variable mechanism 41. This is the same as the connection state switching mechanism 650.

  Next, the pin drive mechanism 200 that switches the axial position of the pin array 700 will be described. As shown in FIG. 3, the first variable mechanism 41 and the second variable mechanism 42 have a first slide arm 81 and a second slide that abut against the end of the sixth pin 76 and slide the pin row 700 in the axial direction, respectively. A slide arm 82 is provided. The first slide arm 81 and the second slide arm 82 are slidable on the outer peripheral surface of the rocker shaft 50 along the axial direction, and are axial with respect to the first link shaft 51 inserted into the rocker shaft 50. It is attached so that relative movement is impossible. Therefore, the first slide arm 81 and the second slide arm 82 are configured to move in the axial direction integrally with the first link shaft 51. The distance between the first slide arm 81 and the second slide arm 82 is the same as the distance between the roller rocker arm 6 of the first variable mechanism 41 and the roller rocker arm 6 of the second variable mechanism. The first slide arm 81 and the second slide arm 82 are formed in the same shape. Hereinafter, when it is not necessary to distinguish between the first slide arm 81 and the second slide arm 82, they are simply referred to as the slide arm 8.

  The slide arm 8 is formed in a plate shape, and the plate surface on one side always abuts perpendicularly to the end of the sixth pin 76 to restrict the movement of the pin row 700 biased by the pin return spring 77. The pin return spring 77 is a pressing surface that presses in the direction of compression. The sixth pin 76 swings with the swing of the second roller rocker arm 62. Accordingly, the pressing surface of the slide arm 8 is formed flat because the end of the sixth pin 76 is a sliding surface, and the end of the sixth pin 76 is in the entire region of the swinging locus of the sixth pin 76. The pressing area is secured so that can be pressed.

  The fourth variable mechanism 44 is provided with a first slide swing arm 91 that contacts the end of the sixth pin 76 of the fourth variable mechanism 44 and slides the pin array 700 in the axial direction. The third variable mechanism 43 is provided with a second slide swing arm 92 that contacts the end of the sixth pin 76 of the third variable mechanism 43 and slides the pin row 700 in the axial direction. The first slide rocking arm 91 and the second slide rocking arm 92 are capable of sliding movement along the axial direction and sliding rotation along the circumferential direction with respect to the outer peripheral surface of the rocker shaft 50, and the rocker The second link shaft 52 inserted in the shaft 50 is attached so as not to be relatively movable in the axial direction. The distance between the first slide swing arm 91 and the second slide swing arm 92 is the same as the distance between the roller rocker arm 6 of the third variable mechanism 43 and the roller rocker arm 6 of the fourth variable mechanism 44. . The first slide swing arm 91 and the second slide swing arm 92 are formed in the same shape. Hereinafter, when it is not necessary to distinguish between the first slide swing arm 91 and the second slide swing arm 92, they are collectively referred to as the slide swing arm 9.

  The slide swing arm 9 is formed in a plate shape, and the plate surface on one side always abuts against the end of the sixth pin 76 to restrict the movement of the pin row 700 biased by the pin return spring 77. The pin return spring 77 is a pressing surface that presses in the direction of compression. Accordingly, the pressing surface of the slide rocking arm 9 is formed flat because the end of the sixth pin 76 slides, and the sixth pin 76 regardless of the rocking angle of the slide rocking arm 9. The pressing area is ensured so that the end of the sixth pin 76 can be pressed over the entire swing trajectory.

  As shown in FIGS. 10 and 11, a columnar insertion / removal pin 9 a that can be inserted into / removed from a spiral groove 112, 122 described later is provided on one side of the slide swing arm 9. A pressing piece 9b is integrally formed on the side of the slide swing arm 9 opposite to the insertion / removal pin 9a across the rocker shaft 50.

  FIG. 12 shows a structure in which the slide swing arm 9 is pivotally supported on the rocker shaft 50. The slide swing arm 9 is formed with an insertion hole 95 for inserting the rocker shaft 50 in a direction perpendicular to the plate surface. A pin press-fitting hole 96 is formed on the end face of the slide swing arm 9 in a direction perpendicular to the insertion hole 95. On the other hand, on the outer peripheral surface of the rocker shaft 50, as shown in FIG. 13, an opening 50a having a predetermined size is formed at an axial position where the slide rocking arm 9 should be supported. The second link shaft 52 inserted into the rocker shaft 50 is formed with a small diameter portion 52a.

  By inserting the rocker shaft 50 through the insertion hole 95, the slide rocking arm 9 is pivotally supported so as to be rotatable with respect to the rocker shaft 50 and movable in the axial direction. And it fixes to the pin press-fit hole 96 in the state where the opening 50a of the rocker shaft 50, the small diameter portion 52a formed in the second link shaft 52, and the pin press-fit hole 96 of the slide swing arm 9 face each other. By fixing the pin 97, the fixing pin 97 is fixed to the pin press-fitting hole 96. In this state, the distal end of the fixing pin 97 faces the small diameter portion 52a formed on the second link shaft 52, but is not fitted into the small diameter portion 52a and can move in the circumferential direction around the small diameter portion 52a. . Therefore, the slide rocking arm 9 can be moved relative to the rocker shaft 50 in the axial direction and rocked about the axis in a range in which the fixing pin 97 can move in the opening 50a of the rocker shaft 50. .

  Further, regarding the structure in which the slide arm 8 is pivotally supported on the rocker shaft 50, the shape of the opening 50b (see FIG. 14) formed in the rocker shaft 50 in the above-described structure in which the slide swing arm 9 is pivotally supported on the rocker shaft 50. Are only different. That is, since the slide arm 8 only slides on the surface of the rocker shaft 50 in the axial direction and does not need to swing in the circumferential direction, the circumferential dimension of the opening 50b is approximately the same as the diameter of the fixing pin 97. It has become. Similarly to the structure of the slide swing arm 9, the slide arm 8 can be moved relative to the first link shaft 51 in the axial direction by press-fitting the fixing pin 97, so that the slide arm 8 can be moved to the first link. The surface of the rocker shaft 50 can be slid integrally with the shaft 51. In FIG. 12, the reference numerals in parentheses correspond to the structure in which the slide arm 8 is pivotally supported on the rocker shaft 50. Reference numeral 51 a represents a small diameter portion 51 a formed on the first link shaft 51.

  The first slide swing arm 91 swings about the rocker shaft 50 as the center of rotation by the operation of the first actuator 101. The second slide swing arm 92 swings about the rocker shaft 50 as the center of rotation by the operation of the second actuator 102. FIG. 10 shows a state where the first slide swing arm 91 or the second slide swing arm 92 is not swinging, and FIG. 11 shows that the first slide swing arm 91 or the second slide swing arm 92 is the first. A state in which the actuator 1 or 101 is oscillated by a predetermined angle is shown.

  The first actuator 101 and the second actuator 102 are configured by, for example, electromagnetic solenoids. When the first actuator 101 is energized, the movable shaft 101a (plunger) advances and pushes the pressing piece 9b of the first slide swing arm 91. As a result, the first slide swing arm 91 swings around the rocker shaft 50 as the center of rotation. Similarly, when the second actuator 102 is energized, the movable shaft 102a moves forward and pushes the pressing piece 9b of the second slide swing arm 92. As a result, the second slide swing arm 92 swings about the rocker shaft 50 as the center of rotation.

  As shown in FIG. 15, the second link shaft 52 has a small-diameter portion 52b at an intermediate position in the axial direction. In addition, a U-shaped spring receiving ring 131 is fitted into the rocker shaft 50 so as to face the small diameter portion 52 b of the second link shaft 52 at a position facing the small diameter portion 52 b. . A shaft return spring 132, which is a compression coil spring, is interposed between one of the stepped portions (ring-shaped wall surfaces) formed on both sides of the small diameter portion 52b and the spring receiving ring 131.

  Therefore, the second link shaft 52 is always pivoted by the shaft return spring 132 in a state where the slide rocking arm 9 is urged away from the roller rocker arm 6 of the cylinder (in the direction of arrow b in FIG. 3). It is provided to be movable in the direction. Hereinafter, a mechanism that constantly urges the second link shaft 52 in the axial direction is referred to as a shaft return mechanism 130.

  The second link shaft 52 is urged in the axial direction by the shaft return spring 132, but the axial movement is restricted by a stopper (not shown). The position where the slide swing arm 9 is maximally separated from the roller rocker arm 6 of the cylinder is called a first position (reference position in the present invention). As the stopper, for example, a configuration in which a member that contacts the plate surface of the slide rocking arm 9 is provided at the first position to restrict movement is preferable, but one side of the step portion of the small diameter portion 52b (the shaft return spring 132 is provided). The structure may be such that the movement is restricted by the contact between the non-contacting side) and the spring receiving ring 131, or the fixing pin 97 press-fitted into the slide rocking arm 9 and the opening 50a (or opening 50b) formed in the rocker shaft 50. It is also possible to adopt a configuration in which movement is restricted by contact with the edge portion.

  As shown in FIG. 3, a cylindrical first spiral groove forming body 111 having a larger outer diameter than the camshaft 30 is formed on the camshaft 30 on the outside of the first cam 31 of the fourth cylinder 14. . The first spiral groove forming body 111 is provided on the movement locus of the insertion / removal pin 9 a due to the swing of the first slide swing arm 91. A first spiral groove 112 extending in a spiral shape is formed on the outer peripheral surface of the first spiral groove forming body 111. The width of the first spiral groove 112 is slightly larger than the outer diameter of the insertion / removal pin 9a. The start end portion 112 a and the end end portion 112 b of the first spiral groove 112 are separated by A millimeter (referred to as a distance A) in the axial direction of the camshaft 30. Further, the end portion 112b of the first spiral groove 112 is formed so that the depth of the groove becomes shallower toward the end. Note that the first spiral groove 112 does not need to be formed in a spiral shape throughout, and for example, a part thereof may include an arc groove portion extending in a circumferential direction orthogonal to the axial direction. In the first spiral groove 112 in the present embodiment, an arc groove portion extending in the circumferential direction is formed at the start end portion 112a and the end end portion 112b. Hereinafter, in the first spiral groove 112, a portion that is substantially a spiral groove excluding the arc groove portions at both ends (the start end portion 112a and the end portion 112b) is referred to as a spiral groove portion.

  The first spiral groove 112 includes an insertion / removal pin 9a formed on the first slide swing arm 91 and a start end 112a of the first spiral groove 112 when the first slide swing arm 91 is located at the first position. Are formed at the same position in the axial direction. Further, the terminal end 112b of the first spiral groove 112 is closer to the first cam 31 of the fourth cylinder 14 in the axial direction than the start end 112a. The circumferential position from the start point to the end point of the spiral groove portion in the first spiral groove 112 is determined by the first cam 31, the second cam 32, and the third cam in the third variable mechanism 43 and the fourth variable mechanism 44. The base circle portions 33 are set within the period in which they are in contact with the first roller 611, the second roller 621, and the third roller 631, respectively, that is, at circumferential positions included in the base circle period T1 shown in FIG. Yes. FIG. 16 is a graph showing the valve lift timing in each of the cylinders 11, 12, 13, and 14. The vertical axis represents the valve lift amount, and the horizontal axis represents the camshaft rotation angle.

  The first slide swing arm 91 swings about the rocker shaft 50 as the center of rotation when the pressing piece 9b is pushed by a predetermined stroke by the first actuator 101 while being in the first position. Thereby, the insertion / removal pin 9a formed on the first slide swing arm 91 is inserted into the first spiral groove 112 (see FIG. 11).

  In addition, the first slide swing arm 91 swings in a direction opposite to the direction pressed by the first actuator 101 by its own weight when the pressing piece 9b is not pressed by the first actuator 101. The insertion / removal pin 9a comes out of the first spiral groove 112 (see FIG. 10). The position when the first slide swing arm 91 is not pressed by the first actuator 101 may be configured to be kept constant by bringing the fixing pin 97 into contact with the edge of the opening 50a, for example. In addition, a stopper (not shown) may be provided to hold the first slide swing arm 91.

  When the first slide swing arm 91 is pushed and swung by the first actuator 101 at the first position, the insertion / removal pin 9 a enters the first spiral groove 112 of the first spiral groove forming body 111. At this time, since the first spiral groove forming body 111 rotates integrally with the camshaft 30, the insertion / removal pin 9 a is pressed against the vertical wall surface 112 c on one side of the first spiral groove 112. As a result, the first slide swing arm 91 slides in the axial direction on the outer peripheral surface of the rocker shaft 50. The force by which the first slide swing arm 91 moves in the axial direction is transmitted to the second slide swing arm 92 via the second link shaft 52. Accordingly, the second slide swing arm 92 also slides in the axial direction integrally with the first slide swing arm 91. At this time, in the shaft return mechanism 130, the shaft return spring 132 is further compressed as the second link shaft 52 moves.

  Thus, the sixth pin 76 of the third variable mechanism 43 and the fourth variable mechanism 44 is pushed in the axial direction by the first slide swing arm 91 and the second slide swing arm 92, respectively. During the period in which the insertion / removal pin 9 a moves through the spiral groove portion of the first spiral groove 112, the base circular portions of the first cam 31, the second cam 32, and the third cam 33 in the third variable mechanism 43 and the fourth variable mechanism 44. Are set within a period in contact with the first roller 611, the second roller 621, and the third roller 631, respectively. Accordingly, during the period in which the first slide swing arm 91 and the second slide swing arm 92 move in the axial direction, the pin hole row 600 of the third variable mechanism 43 and the pin hole row 600 of the fourth variable mechanism 44 are: They are arranged in a straight line. Therefore, the pin rows 700 of the third variable mechanism 43 and the fourth variable mechanism 44 move together in the direction of arrow a in FIG. 3 against the bias of the pin return spring 77.

  The two slide swing arms 91 and 92 stop moving in the axial direction when the insertion / removal pin 9a of the first slide swing arm 91 reaches the end point from the start point of the spiral groove portion of the first spiral groove 112. At this time, the slide rocking arms 91 and 92 have moved in the axial direction by a distance A from the first position. Hereinafter, this position is referred to as a second position.

  When the insertion / removal pin 9a passes through the terminal end 112b of the first spiral groove 112, the insertion / removal pin 9a comes out of the groove. Therefore, the slide rocking arms 91 and 92 may return in the axial direction (in the direction of arrow b in FIG. 3) due to the urging force of the shaft return spring 132 and the pin return spring 77. Therefore, the first slide swing arm 91 is provided with a mechanism for holding it in the second position.

  As shown in FIGS. 17 and 18, a recess 9 c is formed in the pressing piece 9 b of the first slide swing arm 91. When the first actuator 101 is energized when the first slide swing arm 91 is located at the first position, the pressing piece 9b is pressed by the movable shaft 101a of the first actuator. As described above, the first slide swing arm 91 moves along the axial direction of the rocker shaft 50 by the operation of the first actuator 101. For this reason, the position where the pressing piece 9b is pressed by the movable shaft 101a of the first actuator 101 (the position indicated by hatching in FIG. 17) also changes.

  The recess 9c is a groove having a width slightly larger than the diameter of the movable shaft 101a, and is formed in a direction in which the position pushed by the movable shaft 101a changes. The starting end of the recess 9c is formed to be surrounded by a semi-cylindrical inner wall surface.

  When the first slide swing arm 91 moves in the axial direction of the rocker shaft 50, the position at which the movable shaft 101a presses the pressing piece 9b also changes as shown in FIGS. When the first slide swing arm 91 reaches the second position, the movable shaft 101a reaches the recess 9c and falls into the recess 9c. Thus, even when the insertion / removal pin 9a comes out of the first spiral groove 112, the side surface of the movable shaft 101a is locked to the inner wall surface of the recess 9c, so that the first slide swing arm 91 is held in the second position. Is done. Accordingly, the second link shaft 52 and the second slide swing arm 92 are also held in the second position. In this case, since the side surface of the movable shaft 101a and the inner wall surface of the recess 9c are pressed against each other by the urging force of the shaft return spring 132 and the pin return spring 77, the second position can be reliably held. .

  Next, a configuration in which the second link shaft 52 is slid in the axial direction by the operation of the second actuator 102 will be described.

  As shown in FIG. 3, the camshaft 30 has a columnar first shaft having an outer diameter larger than that of the camshaft 30 between the first cam 31 of the third cylinder 13 and the third cam 31 of the fourth cylinder 14. Two spiral groove forming bodies 121 are formed. The second spiral groove forming body 121 is provided on the movement locus of the insertion / removal pin 9 a by the swing of the second slide swing arm 92. A second spiral groove 122 extending in a spiral shape is formed on the outer peripheral surface of the second spiral groove forming body 121. The width of the second spiral groove 122 is slightly larger than the outer diameter of the insertion / removal pin 9a. The start end portion 122 a and the end end portion 122 b of the second spiral groove 122 are separated by B millimeters (referred to as a distance B) in the axial direction of the camshaft 30. The distance B is longer than the distance A and is set to be twice the distance A. Further, the end portion 122b of the second spiral groove 122 is formed so that the depth of the groove becomes shallower toward the end. Note that the second spiral groove 122 does not need to be formed in a spiral shape throughout, and for example, a part of the second spiral groove 122 may include an arc groove portion extending in a circumferential direction orthogonal to the axial direction. In the second spiral groove 122 in the present embodiment, an arc groove portion extending in the circumferential direction is formed at the start end portion 122a and the end end portion 122b. Hereinafter, in the second spiral groove 122, a portion that is substantially a spiral groove excluding the arc groove portions at both ends (the start end portion 122a and the end portion 122b) is referred to as a spiral groove portion.

  The second spiral groove 122 includes an insertion / removal pin 9a formed on the second slide swing arm 92 and a start end portion 122a of the second spiral groove 122 when the second slide swing arm 92 is located at the first position. Are formed at the same position in the axial direction. Further, the end portion 122b of the second spiral groove 122 is closer to the first cam 31 of the third cylinder 13 in the axial direction than the start end portion 122a. The circumferential position from the start point to the end point of the spiral groove portion in the second spiral groove 122 is the same as that of the first spiral groove 112 in the third variable mechanism 43 and the fourth variable mechanism 44 in the first cam 31. , During the period in which the base circle portions of the second cam 32 and the third cam 33 are in contact with the first roller 611, the second roller 621, and the third roller 631, respectively, that is, during the base circle period T1 shown in FIG. It is set to the included circumferential position.

  The second slide swing arm 92 swings about the rocker shaft 50 as the center of rotation when the pressing piece 9b is pushed by a predetermined stroke by the second actuator 102 in a state of being in the first position. As a result, the insertion / removal pin 9 a formed on the second slide swing arm 92 is inserted into the second spiral groove 122.

  Further, the second slide swing arm 92 swings in a direction opposite to the direction pushed by the second actuator 102 by its own weight when the pressing piece 9b is not pushed by the second actuator 102. The insertion / removal pin 9 a comes out of the second spiral groove 122. The position when the second slide swing arm 92 is not pushed by the second actuator 102 may be configured to be kept constant by bringing the fixing pin 97 into contact with the edge of the opening 50a, for example. In addition, a stopper (not shown) may be provided to hold the second slide swing arm 92.

  When the second slide swing arm 92 is pushed and swung by the second actuator 102 at the first position, the insertion / removal pin 9a enters the second spiral groove 122 of the second spiral groove forming body 121. Accordingly, the second slide swing arm 92 slides in the axial direction on the outer peripheral surface of the rocker shaft 50 when the insertion / removal pin 9a is pushed by the vertical wall surface 122c on one side of the second spiral groove 122. The force by which the second slide swing arm 92 moves in the axial direction is transmitted to the first slide swing arm 91 via the second link shaft 52. Accordingly, the first slide swing arm 91 also slides in the axial direction integrally with the second slide swing arm 92. At this time, in the shaft return mechanism 130, the shaft return spring 132 is further compressed as the second link shaft 52 moves.

  Thus, the pin array 700 of the third variable mechanism 43 and the fourth variable mechanism 44 is integrated against the bias of the pin return spring 77 in the same manner as when the first slide swing arm 91 is swung. It moves in the direction of arrow a in FIG.

  The two slide rocking arms 91 and 92 stop moving in the axial direction when the insertion / removal pin 9a of the second slide rocking arm 92 reaches the end point from the start point of the spiral groove portion of the second spiral groove 122. At this time, the two slide rocking arms 91 and 92 have moved in the axial direction by a distance B from the first position. Hereinafter, this position is referred to as a third position.

  When the insertion / removal pin 9 a passes through the terminal end 122 b of the second spiral groove 122, the insertion / removal pin 9 a comes out of the groove. Therefore, the slide rocking arms 91 and 92 may return in the axial direction (in the direction of arrow b in FIG. 3) due to the urging force of the shaft return spring 132 and the pin return spring 77. Therefore, the second slide rocking arm 92 is provided with a holding mechanism similar to the first slide rocking arm 91 in order to hold it in the third position. That is, when the second slide swing arm 92 moves relative to the pressing piece 9b of the second slide swing arm 92 relative to the movable shaft 102a of the second actuator 102 by the distance B in the axial direction, the second actuator 102 A concave portion 9c into which the movable shaft 102a falls is formed. Therefore, the holding mechanism in the second slide rocking arm 92 is different from the holding mechanism in the first slide rocking arm 91 only in the formation position of the recess 9c, and the mechanism is the same.

  In the rocker shaft 50, as shown in FIGS. 19 and 20, a coupling type delay mechanism 140 is provided between the first link shaft 51 and the second link shaft 52. The coupled delay mechanism 140 compresses the coil spring 141 with the force of the second link shaft 52 moving in the axial direction, and when the first link shaft 51 becomes movable in the axial direction, that is, the first variable mechanism. When the pin hole row 600 of 41 and the second variable mechanism 42 are aligned on the same straight line, the urging force of the coil spring 141 moves the first link shaft 52 in the same direction by the distance moved by the second link shaft 52. It is something to be made.

  The first link shaft 51 is formed with a small-diameter cylindrical portion 51c that is processed to have a small diameter at the tip that is on the second link shaft 52 side. A pin press-fit hole 51d is formed in the middle position of the small diameter cylindrical portion 51c. On the other hand, in the second link shaft 52, a circular hole 52c into which the small-diameter cylindrical portion 51c is inserted with play is formed along the axial direction. Further, the second link shaft 52 is formed with openings 52d penetrating the circular hole 52c vertically on both sides of the small diameter cylindrical portion 51c. The opening 52d is a long hole extending in the axial direction, and both ends in the longitudinal direction are formed in a semicircular shape.

  The first link shaft 51 and the second link shaft 52 are inserted into the circular hole 52c of the second link shaft 52 in a state where the coil spring 141 is inserted into the small diameter cylindrical portion 51c. The movement restricting pin 142 is inserted from the formed one opening 52d, and the movement restricting pin 142 is press-fitted into the pin press-fitting hole 51d of the small-diameter cylindrical portion 51c. In this connected state, the coil spring 141 is interposed between the step portion of the first link shaft 51 (ring-shaped plane around the base portion of the small-diameter cylindrical portion 51 c) and the ring-shaped end portion of the second link shaft 52. It will be. Further, the movement restricting pin 142 is press-fitted and fixed in the pin press-fitting hole 51d at the center position, and the side surfaces of both ends face the edge of the opening 52d. Further, the length of the movement restricting pin 142 is set such that both ends do not protrude radially outward from the opening 52d.

  In this coupled delay mechanism 140, the first link shaft 51 and the second link shaft 52 are urged away from each other by the coil spring 141. Therefore, the movement restricting pin 142 press-fitted into the small-diameter cylindrical portion 51c of the first link shaft 51 is connected to the end portion of the opening 52d formed in the second link shaft 52 (the end portion on the side close to the first link shaft 51). ) And the axial relative position between the link shafts 51 and 52 is kept constant.

  When the first actuator 101 or the second actuator 102 is operated and the first slide swing arm 91 or the second slide swing arm 92 moves on the surface of the rocker shaft 50 in the axial direction, the second link shaft is accordingly moved. 52 also moves in the axial direction. During the period in which the slide rocking arms 91 and 92 can move in the axial direction, the bases of the first cam 31, the second cam 32, and the third cam 33 in the third variable mechanism 43 and the fourth variable mechanism 44 as described above. This is a period in which the circular portions are in contact with the first roller 611, the second roller 621, and the third roller 631, respectively. At this time, in the first variable mechanism 41 and the second variable mechanism 42, it is a period during which any of the roller rocker arms 61, 62, 63 is oscillating, and the pin hole row 600 is not arranged in a straight line.

  Therefore, since the pin row 700 cannot be moved in the axial direction by the two slide arms 81 and 82 connected to the first link shaft 51, the first link shaft 51 is maintained in a stopped state. In this state, the movement restricting pin 142 is moved in the direction of the arrow in FIG. The relative movement distance of the movement regulating pin 142 with respect to the opening 52d is the same as the movement distance of the second link shaft 52, and is the distance A when the first actuator 101 is operated, and when the second actuator 102 is operated. Distance B. When only the second link shaft 52 is moving, the coil spring 141 is compressed, so that the two slide arms 81 and 82 axially move the sixth pin 76 of the variable mechanisms 41 and 42 (FIG. 3). In the direction of arrow a).

  Note that the opening 52d formed in the second link shaft 52 is set to a size such that even when the movement restricting pin 142 moves, the movement restricting pin 142 does not hit the edge in the moving direction. Further, the circular hole 52c formed in the second link shaft 52 prevents the tip of the small diameter cylindrical portion 51c of the first link shaft 51 from hitting the bottom of the circular hole 52c even when the second link shaft 52 moves. The depth is set.

  As the camshaft 30 rotates, the base circles of the first cam 31, the second cam 32, and the third cam 33 in the first variable mechanism 41 and the second variable mechanism 42 are the first roller 611 and the second roller 621, respectively. When in contact with the third roller 631, the pin hole rows 600 in the first variable mechanism 41 and the second variable mechanism 42 are arranged in a straight line. Accordingly, the pin row 700 can be moved in the axial direction, and the first link shaft 51 moves in the axial direction together with the slide arms 81 and 82 by the urging force of the compressed coil spring 141 to move the pin row 700. The spring force of the coil spring 141 is set larger than the spring force of the pin return spring 77 of the variable mechanisms 41 and 42.

  At this time, the movement restricting pin 142 returns to the axial direction in the opening 52d formed in the second link shaft 52 and stops by contacting the edge of the opening 52d which is the initial position (the state of FIGS. 19 and 20). . Accordingly, the first link shaft 51 moves by the distance that the second link shaft 52 has moved first, and further movement is restricted. As described above, in the combined delay mechanism 140, the axial movement of the first link shaft 51 is delayed with respect to the axial movement of the second link shaft 52, and the moving distance of the first link shaft 51 is set to be the second link shaft 52. The moving distance can be the same.

  Next, the connection state of the variable mechanism 4 in the first position, the second position, and the third position described above will be described. First, the connection state of the variable mechanism 4 in the first position will be described. The first position is such that when the first actuator 101 and the second actuator 102 are not operating, the link shafts 51 and 52 are located closest to the fourth cylinder 14 side by the bias of the shaft return spring 132 (arrow b in FIG. 3). Direction). In this first position, the slide arms 81 and 82 and the slide rocking arms 91 and 92 are located farthest from the second roller rocker arm 62.

  In the first position, as shown in FIG. 4, the pins 71 to 76 are set in the following positional relationship with respect to the pin holes 613, 623, 624, and 633. The axial position of the abutting surface where the first pin 71 and the spring force transmission member 78 abut is the boundary position between the third roller rocker arm 63 and the second roller rocker arm 62. Further, the axial position of the abutting surface where the first pin 71 and the second pin 72 abut is an intermediate position of the second main pin hole 623. Further, the axial position of the abutting surface where the second pin 72 and the third pin 73 abut is an intermediate position of the first pin hole 613. Further, the axial position of the contact surface where the third pin 73 and the fourth pin 74 abut is the boundary position between the first roller rocker arm 61 and the sub arm 62 b of the second roller rocker arm 62. Further, the axial position of the abutting surface where the fourth pin 74 and the fifth pin 75 abut is an intermediate position of the second auxiliary pin hole 624. Further, the axial position of the contact surface where the fifth pin and the sixth pin are in contact is the intermediate position of the second auxiliary pin hole 624.

  Therefore, in the first position, the second pin 72 is inserted across the first roller rocker arm 61 and the second roller rocker arm 62. For this reason, the first roller rocker arm 61 and the second roller rocker arm 62 are connected to each other, so that the first roller rocker arm 61 and the second roller rocker arm 62 are integrally pivotable about the rocker shaft 50. Further, the third roller rocker arm 63 is in a state of being able to swing around the rocker shaft 50 as a center of rotation while being separated from the second roller rocker arm 62.

  In this state, since the lift amount of the second cam 32 is substantially zero, the intake valve 20 opens and closes according to the cam profile of the first cam 31.

  Next, the connection state of the variable mechanism 4 in the second position will be described. The second position is a state in which the first actuator 101 is operated and the link shafts 51 and 52 are moved to the first cylinder 11 side (in the direction of arrow a in FIG. 3) by a distance A from the first position. . In this second position, as shown in FIG. 5, the pins 71 to 76 are set in the following positional relationship with respect to the pin holes 613, 623, 624, and 633. The axial position of the contact surface where the first pin 71 and the spring force transmission member 78 contact is an intermediate position of the third pin hole 633. Further, the axial position of the contact surface where the first pin 71 and the second pin 72 abut is the boundary position between the third roller rocker arm 63 and the second roller rocker arm 62. Further, the axial position of the contact surface where the second pin 72 and the third pin 73 abut is the boundary position between the main arm 62 a of the second roller rocker arm 62 and the first roller rocker arm 63. In addition, the axial position of the abutting surface where the third pin 73 and the fourth pin 74 abut is an intermediate position of the first pin hole 613. Further, the axial position of the contact surface where the fourth pin 74 and the fifth pin 75 abut is the boundary position between the first roller rocker arm 61 and the sub arm 62 b of the second roller rocker arm 62. Further, the axial position of the contact surface where the fifth pin 75 and the sixth pin 76 abut is an intermediate position of the second sub pin hole 624.

  Therefore, in the second position, the first roller rocker arm 61, the second roller rocker arm 62, and the third roller rocker arm 63 are all disconnected. For this reason, the first roller rocker arm 61 is swung by the rotation of the first cam 31, and the third roller rocker arm 63 is swung by the rotation of the third cam 33. Not transmitted to.

  Therefore, in this state, the intake valve 20 opens and closes according to the cam profile of the second cam 32. For this reason, in a 2nd position, it will be in a valve rest state.

  Next, the connection state of the variable mechanism 4 in the third position will be described. The third position is a state in which the second actuator 102 is operated and the link shafts 51 and 52 are moved toward the first cylinder 11 (in the direction of arrow a in FIG. 3) by a distance B from the first position. . In this third position, as shown in FIG. 6, the pins 71 to 76 are set in the following positional relationship with respect to the pin holes 613, 623, 624, and 633. The axial position of the contact surface where the first pin 71 and the spring force transmission member 78 contact is an intermediate position of the third pin hole 633. In addition, the axial position of the contact surface where the first pin 71 and the second pin 72 abut is also an intermediate position of the third pin hole 633. In addition, the axial position of the contact surface where the second pin 72 and the third pin 73 are in contact is the intermediate position of the second main pin hole 623. Further, the axial position of the contact surface where the third pin 73 and the fourth pin 74 abut is the boundary position between the main arm 62 a of the second roller rocker arm 62 and the first roller rocker arm 61. In addition, the axial position of the abutting surface where the fourth pin 74 and the fifth pin 75 abut is an intermediate position of the first pin hole 613. Further, the axial position of the contact surface where the fifth pin 75 and the sixth pin 76 abut is the boundary position between the first roller rocker arm 61 and the sub arm 62 b of the second roller rocker arm 62.

  Therefore, in the third position, the second pin 72 is inserted across the second roller rocker arm 62 and the third roller rocker arm 63. For this reason, since the second roller rocker arm 62 and the third roller rocker arm 63 are connected to each other, the second roller rocker arm 62 and the third roller rocker arm 63 are integrally pivotable about the rocker shaft 50. Further, the first roller rocker arm 61 is in a state of being able to swing around the rocker shaft 50 as a center of rotation while being separated from the second roller rocker arm 62.

  In this state, since the lift amount of the second cam 32 is substantially zero, the intake valve 20 opens and closes according to the cam profile of the third cam 32.

  As described above, in the variable mechanism 4, the intake valve 20 is connected to the second roller rocker arm 62 that swings according to the cam profile of the second cam 32 having the smallest valve lift, and both sides of the second roller rocker arm are connected. By switching the connection state of the roller rocker arms 61 and 63 provided in the valve, valve characteristics corresponding to the cam profiles of the other two cams 31 and 33 are selectively obtained.

  Next, drive control in the pin drive mechanism 200 will be described. The first actuator 101 and the second actuator 102 are electrically driven and controlled by the ECU 150. The ECU 150 is an electronic control unit for controlling the operating state of the internal combustion engine 10. The ECU 150 drives and controls the first actuator 101 and the second actuator 102 based on the output signal of the cam position sensor 201 that detects the rotation angle of the camshaft 30.

  Switching of the coupling state of the variable mechanism 4 is such that the base circles of the first cam 31, the second cam 32, and the third cam 33 are in contact with the first roller 611, the second roller 621, and the third roller 631, respectively. Although it is necessary to carry out within the base circle period T1 (see FIG. 16), all the cylinders 11, 12, 13, and 14 do not have such a state at the same time. Therefore, when the third cylinder 13 and the fourth cylinder 14 are within the base circle period T1, the pin train 700 of the third variable mechanism and the fourth variable mechanism is moved, and then the first cylinder 11 and A base circle period T2 in which the base circle portions of the first cam 31, the second cam 32, and the third cam 33 in the second cylinder 12 are in contact with the first roller 611, the second roller 621, and the third roller 631, respectively (FIG. 16), the pin row 700 of the first variable mechanism 41 and the second variable mechanism 42 is moved.

  The starting point of the spiral groove portion in the first spiral groove 112 and the second spiral groove 122 is set to the start point of the base circle period T1 or a point immediately thereafter. Further, the end point of the spiral groove portion in the first spiral groove 112 and the second spiral groove 122 is set to the end point of the base circle period T1 or a point in front thereof. Accordingly, when the ECU 150 switches the second link shaft 52 from the first position to the second position or the third position, the ECU 150 reads the output signal of the cam position sensor 201, and the insertion / removal pin 9a is connected to the first spiral groove 112 or the second position. The first actuator 101 or the second actuator 102 is detected when the rotation angle of the camshaft 30 that falls to a position slightly ahead of the starting point of the spiral groove portion of the spiral groove 122 (the start end of the groove or its front position) is detected. Is activated.

  The ECU 150 selects the first position when the internal combustion engine 10 is operated at a high load. In this case, the ECU 150 does not operate the first actuator 101 and the second actuator 102. Therefore, the intake valve 20 opens and closes according to the cam profile of the first cam 31 and generates torque suitable for high load operation.

  The ECU 150 selects the third position when the internal combustion engine 10 is operated at a low / medium load. For example, when switching from the first position to the third position, the ECU 150 operates the second actuator 102 (does not operate the first actuator 101). Thereby, the second actuator 102 pushes the pressing piece 9b of the second slide swing arm 92, the second slide swing arm 92 swings, and the insertion / removal pin 9a enters the start end portion 122a of the second spiral groove 122. To do. The insertion / removal pin 9a moves in the second spiral groove 122 toward the terminal end 122b while being pushed by the vertical wall surface 122c on one side of the second spiral groove 122 by the rotation of the second spiral groove forming body 121. Thus, the second slide rocking arm 92 slides in the axial direction on the outer peripheral surface of the rocker shaft 50, and accordingly, the second link shaft 52 and the first slide rocking arm 91 are also separated from the second slide rocking arm 92. Moves axially as a unit.

  During this movement, the coil spring 141 of the combined delay mechanism 140 is compressed by the amount of movement of the second link shaft 52. When the insertion / removal pin 9 a reaches the end portion 122 b of the second spiral groove 122, the movable shaft 102 a of the second actuator 102 falls into the recess 9 c formed in the pressing piece 9 b of the second slide swing arm 92. Therefore, even if the insertion / removal pin 9a comes out of the second spiral groove 122, the side surface of the movable shaft 102a is locked to the inner wall surface of the recess 9c, so that the second slide swing arm 92 is axially moved from the first position. Is held at the third position moved by the distance B. At this time, only the third variable mechanism 43 and the fourth variable mechanism 44 are switched to the third position.

  In this state, the first link shaft 51 is urged in the direction of the first cylinder 11 (the direction of arrow a in FIG. 3) by the coil spring 141 of the coupled delay mechanism 140. For this reason, the first slide arm 81 and the second slide arm 82 continue to push the sixth pin 76 in the axial direction, respectively. When the cam shaft 30 rotates, the base circles of the first cam 31, the second cam 32, and the third cam 33 come into contact with the first roller 611, the second roller 621, and the third roller 631, respectively. The pin hole row 600 in the first variable mechanism 41 and the second variable mechanism 42 is arranged in a straight line, and the pin row 700 slides in the pin hole row 600 in the axial direction. This moving distance is the same distance B as the moving distance of the second link shaft 52. In this way, all the variable mechanisms 41, 42, 43, 44 are switched to the third position.

  Therefore, since the intake valve 20 opens and closes according to the cam profile of the third cam 33, the Atkinson cycle is performed, the thermal efficiency is increased, and the fuel consumption can be reduced. For this reason, it is suitable for low / medium load operation.

  The ECU 150 selects the second position when performing the fuel cut operation. For example, when switching from the first position to the second position, the ECU 150 operates the first actuator 101 (does not operate the second actuator 102). Accordingly, the first actuator 101 pushes the pressing piece 9b of the first slide swing arm 91, the first slide swing arm 91 swings, and the insertion / removal pin 9a enters the start end 112a of the first spiral groove 112. To do. The insertion / removal pin 9a moves in the first spiral groove 112 toward the terminal end 112b while being pushed by the vertical wall surface 112c on one side of the first spiral groove 112 by the rotation of the first spiral groove forming body 111. Thus, the first slide rocking arm 91 slides in the axial direction on the outer peripheral surface of the rocker shaft 50, and accordingly, the second link shaft 52 and the second slide rocking arm 92 also move with the first slide rocking arm 91. Moves axially as a unit.

  During this movement, the coil spring 141 of the combined delay mechanism 140 is compressed by the amount of movement of the second link shaft 52. When the insertion / removal pin 9 a reaches the terminal end 112 b of the first spiral groove 112, the movable shaft 101 a of the first actuator 101 falls into the recess 9 c formed in the pressing piece 9 b of the first slide swing arm 91. Therefore, even if the insertion / removal pin 9a comes out of the first spiral groove 112, the side surface of the movable shaft 101a is locked to the inner wall surface of the recess 9c, so that the first slide swing arm 91 is axially moved from the first position. Is held at the second position moved by the distance A. At this time, only the third variable mechanism 43 and the fourth variable mechanism 44 are switched to the second position.

  Then, due to the rotation of the camshaft 30, the base circular portions of the first cam 31, the second cam 32, and the third cam 33 in the first variable mechanism 41 and the second variable mechanism 42 become the first roller 611 and the second roller, respectively. 621 and the third roller 631 are brought into contact with each other, the pin hole rows 600 in the first variable mechanism 41 and the second variable mechanism 42 are arranged in a straight line, and the pin is moved by the bias of the coil spring 141 of the combined delay mechanism 140. The row 700 slides in the pin hole row 600 in the axial direction. This moving distance is the same distance A as the moving distance of the second link shaft 52. In this way, all the variable mechanisms 41, 42, 43, 44 are switched to the second position.

  Accordingly, the intake valve 20 opens and closes according to the cam profile of the second cam 32. As a result, during the fuel cut operation, the valve is stopped. When the intake valve 20 opens and closes during the fuel cut operation, fresh air passes through the exhaust purification device provided in the cylinders 11, 12, 13, 14 and the exhaust system of the internal combustion engine 10, and the exhaust purification device There is a possibility that the supported precious metal catalyst is oxidized and the purification performance of the exhaust purification device is deteriorated or lowered. Therefore, in the present embodiment, during the fuel cut operation, the above-described problem can be avoided by setting the intake valve 20 to a resting state.

  Further, the ECU 150 switches from the third position to the first position when switching from the low / medium load operation to the high load operation. In this case, the ECU 150 stops energization of the second actuator 102. This energization stop timing may be arbitrary regardless of the rotation angle of the camshaft 30. As a result, the movable shaft 102a of the second actuator 102 comes out of the recess 9c of the second slide swing arm 92, and the second slide swing arm 92 returns to the initial position by its own weight. As a result, the second link shaft 52, the first slide swing arm 91, and the second slide swing arm 92 are integrated, and the direction of the fourth cylinder 14 (arrow b in FIG. 3) is urged by the bias of the shaft return spring 132. Direction) to return to the first position. In the third variable mechanism 43 and the fourth variable mechanism 44, when the pin row 700 and the pin hole row 600 are aligned by rotation of the camshaft 30, the pin return spring 77 is biased. The pin row 700 returns to a position where it is regulated by the slide swing arms 91 and 92. In the first changing mechanism 41 and the second changing mechanism 42, when the pin row 700 and the pin hole row 600 are aligned, the pin row 700 and the slide arm 81 are biased by the pin return spring 77. , 82 and the first link shaft 51 return in the same direction. In this way, all the variable mechanisms 41, 42, 43, 44 are switched from the third position to the first position.

  Further, the ECU 150 switches from the second position to the first position when switching from the fuel cut operation to the high load operation. In this case, the ECU 150 stops energization of the first actuator 101. This energization stop timing may be arbitrary regardless of the rotation angle of the camshaft 30. As a result, the movable shaft 101a of the first actuator 101 comes out of the recess 9c of the first slide swing arm 91, and the first slide swing arm 91 returns to the initial position by its own weight. Therefore, similarly to the case of switching from the third position to the first position, the variable mechanisms 41, 42, 43, and 44 are switched from the second position to the first position.

  Further, when switching from the fuel cut operation to the low / medium load operation, or when switching from the low / medium load operation to the fuel cut operation, the ECU 150 once returns to the first position and then the third position or the second position. Switch to position.

  Thus, the pin drive mechanism 200 of the present embodiment includes the link shafts 51 and 52, the slide arms 81 and 82, the slide swing arms 91 and 92, the actuators 101 and 102, and the spiral groove forming bodies 111 and 112. And a shaft return mechanism 130, a coupled delay mechanism 140, an ECU 150, and a cam position sensor 201.

  Next, the variable valve gear according to the second embodiment will be described. In the variable valve operating apparatus of the first embodiment, the first actuator 101 and the first spiral groove forming body 111 for switching to the second position, and the second actuator 102 and the second spiral groove forming body for switching to the third position. However, the variable valve operating apparatus according to the second embodiment is configured so that these functions are realized by one actuator and a spiral groove forming body. Hereinafter, a configuration different from the variable valve operating apparatus of the first embodiment will be described.

  FIG. 21 is a schematic configuration diagram illustrating a relationship between the connection state switching mechanism 650 and the pin driving mechanism 210 in the second embodiment. In the second embodiment and the first embodiment, the cams 31, 32, 33 of the cylinders 11, 12, 13, 14, roller rocker arms 61, 62, 63, rocker shaft 50, link shafts 51, 52, slide arm 81, 82, the shaft return mechanism 130, the combined delay mechanism 140, and the connection state switching mechanism 650 are the same, and the pin drive mechanism is different.

  In the second embodiment, a third slide arm 83 is provided as a member for sliding the pin row 700 of the third variable mechanism 43 in the axial direction instead of the second slide swing arm 92 of the first embodiment. The third slide arm 83 is connected to the second link shaft 92 by a fixing pin 97 with the same configuration as the slide arms 81 and 82 of the first embodiment. Since the third slide arm 83 only slides on the surface of the rocker shaft 50 in the axial direction and does not need to swing in the circumferential direction, the connecting portion of the third slide arm 83 is as shown in FIG. In addition, the circumferential dimension of the opening 50 b formed in the rocker shaft 50 is approximately the same as the diameter of the fixing pin 97. The third slide arm 83 has the same shape and the same function as the first and second slide arms 81 and 82.

  The fourth variable mechanism 44 is provided with a slide swing arm 93 that abuts the end portion of the sixth pin 76 and slides the pin row 700 in the axial direction. The slide swing arm 93 is connected to the second link shaft 52 by a fixing pin 97, similarly to the first slide swing arm 91 of the first embodiment. Therefore, the slide rocking arm 93 can slide and rotate along the axial direction with respect to the outer peripheral surface of the rocker shaft 50, and can slide relative to the second link shaft 52. It is attached so that it cannot move relative to the direction.

  The slide swing arm 93 is formed in a plate shape, and the plate surface on one side always abuts against the end of the sixth pin 76 to restrict the movement of the pin row 700 biased by the pin return spring 77. The pin return spring 77 is a pressing surface that presses in the direction of compression. Accordingly, the pressing surface of the slide rocking arm 93 is flat because the end of the sixth pin 76 slides, and the sixth pin 76 is independent of the rocking angle of the slide rocking arm 93. The pressing area is ensured so that the end of the sixth pin 76 can be pressed over the entire swing trajectory. As shown in FIGS. 22 to 24, the slide swing arm 93 has a columnar insertion / removal pin 9 a standing on one side and a pressing piece 9 b on the opposite side of the insertion / removal pin 9 a with the rocker shaft 50 interposed therebetween. It is integrally formed.

  The slide swing arm 93 swings about the rocker shaft 50 as a rotation center when the pressing piece 9 b is pressed by the operation of the actuator 103. The actuator 103 is configured to be able to switch a stroke (referred to as a protruding amount) for pushing the pressing piece 9b of the slide swing arm 93 in two stages. Therefore, the swing angle from the initial position of the slide swing arm 93 can be switched in two stages.

  For example, when an electromagnetic solenoid is used as the actuator 103, the advance / retreat position of the movable shaft 103a is determined by the balance between the return spring 104 and the electromagnetic force generated in the coil 103L, as shown in FIG. Accordingly, by providing the switching element 105 in the energization circuit for the coil 103L and switching the energization amount in two ways by the duty ratio control of the switching element 105, the protrusion amount can be switched in two stages.

  Further, for example, as shown in FIG. 26, a configuration in which two actuators 1031 and 1032 are arranged in series can be employed. For example, when a large protrusion amount is required, the two actuators 1031 and 1032 are operated simultaneously. In this case, since the actuator 1031 located on the rear side pushes the actuator 1032 on the front side, the projecting amount twice as large as the projecting amount of one actuator can be obtained as a whole. Further, when a small protrusion amount is required, only one of the actuators needs to be operated. As actuators 1031 and 1032, hydraulic actuators can be employed in addition to electromagnetic solenoids.

  Hereinafter, of the protrusion amounts that can be switched in two steps, the smaller one is referred to as a first protrusion amount, and the larger one is referred to as a second protrusion amount.

  The camshaft 30 is formed with a cylindrical spiral groove forming body 160 having an outer diameter larger than that of the camshaft 30 outside the first cam 31 of the fourth cylinder 14. The spiral groove forming body 160 is provided on the movement locus of the insertion / removal pin 9 a by the swing of the slide swing arm 93. A spiral two-step groove 170 extending in a spiral shape is formed on the outer peripheral surface of the spiral groove forming body 160. The spiral two-step groove 170 is formed by arranging a first spiral groove 171 and a second spiral groove 172 having different depths in parallel.

  The spiral grooves 112 and 122 in the first embodiment are configured so as to be surrounded by the opposing vertical wall surface and the bottom surface. However, the spiral two-step groove 170 forms only the vertical wall surface and the bottom surface on one side, Opposite sides are open. Similar to the first embodiment, the spiral two-step groove 170 is configured to slide the insertion / removal pin 9a in the axial direction by the rotation of the camshaft 30. Therefore, if the vertical wall surface on the side where the insertion / removal pin 9a is pushed is formed in a spiral shape, the function is achieved. Therefore, in the second embodiment, the bottom surface of the spiral two-step groove 170 is formed in a step shape so that a vertical wall surface for pressing the insertion / removal pin 9a is provided independently above and below. As a result, the spiral two-step groove 170 includes a first spiral groove 171 having a vertical wall surface on the upper stage side (shallow side) and a second spiral groove 172 having a vertical wall surface on the lower stage side (deep side). It has become. In addition, the spiral groove in this invention does not necessarily need to be provided with the vertical wall surface which opposes, but should just have the vertical wall surface of the side which pushes the side surface of the insertion / removal pin 9a.

  27 is a front view of the spiral groove forming body 160, and FIG. 28 is a developed view of the outer peripheral surface of the spiral groove forming body 160. FIG. As shown in the figure, the first spiral groove 171 and the second spiral groove 172 each have a common start end portion 170a. The start end 170a is formed to extend linearly in the circumferential direction. The first vertical wall surface 171c and the second vertical wall surface 172c extending in a spiral shape are formed by making the bottom surface stepped from the middle of the starting end portion 170a. The first vertical wall surface 171c is formed in a spiral shape having a small degree of change in the axial position with respect to the change in the circumferential position, and is provided on the upper stage side. The second vertical wall surface 172c is provided with respect to the change in the circumferential position. Thus, it is formed in a spiral shape having a large degree of change in the axial position and is provided on the lower stage side.

  The shallower bottom surface (that is, the bottom surface on which the first vertical wall surface 171c is erected) is referred to as the first bottom surface 171d, and the deeper bottom surface (that is, the second vertical wall surface 172c is erected). Is called the second bottom surface 172d. The first spiral groove 171 is a part surrounded by the first vertical wall surface 171c and the first bottom surface 171d, and the second spiral groove 172 is surrounded by the second vertical wall surface 172c and the second bottom surface 172d. It becomes a part to be. The depth of the first spiral groove 171 (the depth of the first bottom surface 171d with respect to the outer peripheral surface) is D1. The depth of the second spiral groove 172 (the depth of the second bottom surface 172d with respect to the outer peripheral surface) is D2 (> D1). The start end portion 17a of the spiral double step groove 170 is a bottom surface that is continuous with the second bottom surface 172d.

  The end portion 171b of the first spiral groove 171 and the end portion 172b of the second spiral groove 172 are positions advanced by a predetermined distance in the circumferential direction from the starting points of the first spiral groove 171 and the second spiral groove 172 (the camshaft is at a predetermined angle). The first vertical wall surface 171c and the second vertical wall surface 172c are grooves that extend linearly in the circumferential direction. The end portions 171b and 172b become shallower in the circumferential direction and end at a position advanced by a predetermined distance.

  The start end portion 170 a and the end end portion 171 b of the first spiral groove 171 are separated by a distance A in the axial direction of the camshaft 30. Further, the start end portion 170 a and the end end portion 172 b in the second spiral groove 172 are separated by a distance B in the axial direction of the camshaft 30.

  In the second embodiment, by selectively controlling the protrusion amount of the actuator 103, the spiral groove (the first spiral groove 171 or the second spiral groove) into which the insertion / removal pin 9a formed on the slide swing arm 93 is inserted. 172) is selected. When the pressing piece 9b of the slide swing arm 93 is pushed by the first protruding amount by the actuator 103, the insertion / removal pin 9a is spirally moved by a predetermined distance slightly shallower than the depth D1 due to the swing of the slide swing arm 93. It is inserted into the step groove 170. In this case, the insertion / removal pin 9a is first inserted into the spiral second step groove 170 starting end portion 170a. Then, due to the rotation of the spiral groove forming body 160, the insertion / removal pin 9a slides on the first vertical wall surface 171c while being pushed by the first vertical wall surface 171c while being inserted into the first spiral groove 171. Thus, the slide swing arm 93 slides in the axial direction on the outer peripheral surface of the rocker shaft 50. When the insertion / removal pin 9a reaches the end portion 171b of the first spiral groove 171, the slide swing arm 93 reaches the second position moved by the distance A from the first position.

  Further, when the pressing piece 9b of the slide rocking arm 93 is pushed by the second protruding amount by the actuator 103, the insertion / removal pin 9a is deeper than the depth D1 by the rocking of the slide rocking arm 93, and the depth A predetermined distance slightly shallower than the length D2 is inserted into the spiral two-step groove 170. In this case, the insertion / removal pin 9a is first inserted into the spiral second step groove 170 starting end portion 170a. Then, due to the rotation of the spiral groove forming body 160, the insertion / removal pin 9a slides on the second vertical wall surface 172c while being pushed by the second vertical wall surface 172c while being inserted into the second spiral groove 172. Thus, the slide swing arm 93 slides in the axial direction on the outer peripheral surface of the rocker shaft 50. When the insertion / removal pin 9a reaches the end portion 172b of the second spiral groove 172, the slide swing arm 93 reaches the third position moved by the distance B from the first position.

  The force by which the slide swing arm 93 moves in the axial direction is transmitted to the third slide arm 83 via the second link shaft 52. Accordingly, the third slide arm 83 also slides in the axial direction integrally with the slide swing arm 93. At this time, the shaft return spring 132 is further compressed as the second link shaft 52 moves.

  The insertion / removal pin 9a comes out of the first spiral groove 171 or the second spiral groove 172 when passing through the end portion 171b or the end portion 172b. Therefore, there is a possibility that the slide swing arm 93 may return in the axial direction by the urging force of the shaft return spring 132 and the pin return spring 77. Therefore, the slide swing arm 93 is provided with a mechanism for holding it at the second position or the third position.

  As shown in FIGS. 29 and 30, the pressing piece 9b of the slide swing arm 93 is formed with a two-step recess 9d. When the actuator 103 is energized when the slide rocking arm 93 is located at the first position, the pressing piece 9b is pushed by the movable shaft 103a of the actuator 103, and the axial movement of the slide rocking arm 93 causes the actuator 103 to move. The position pushed by the movable shaft 103a 103 (the position indicated by hatching in FIG. 29) also changes.

  As described above, when the actuator 103 is driven with the first protrusion amount, the slide swing arm 93 needs to be held at a position moved along the axial direction of the rocker shaft 50 by the distance A from the first position. is there. Further, when the actuator 103 is driven with the second protrusion amount, the actuator 103 needs to be held at a position moved along the axial direction of the rocker shaft 50 by a distance B from the first position.

  Therefore, the two-step recess 9d is such that when the actuator 103 is driven with the first protruding amount, the movable shaft 103a of the actuator 103 falls when the slide swing arm 93 moves in the axial direction from the first position by the distance A. When the first groove 9d1 and the actuator 103 are driven with the second protruding amount, the movable shaft 103a of the actuator 103 falls when the slide swing arm 93 moves in the axial direction by the distance B from the first position. And a groove 9d2.

  The movable shaft 103a of the actuator 103 has a small diameter at the distal end side and a large diameter at the proximal end side. The distal end side is called a small diameter portion 103a1, and the proximal end side is called a large diameter portion 103a2.

  The first groove 9d1 in the two-step concave portion 9d is a groove having a width larger than the diameter of the small diameter portion 103a1 and smaller than the diameter of the large diameter portion 103a2, and is formed in a direction in which the position pushed by the movable shaft 103a changes. . The starting end of the first groove 9d1 is formed so as to be surrounded by a semi-cylindrical inner wall surface. The depth of the first groove 9d1 is set to be slightly longer than the axial length of the small diameter portion 103a1 of the movable shaft 103a.

  The second groove 9d2 in the two-step recess 9d is a groove having a width slightly larger than the diameter of the large-diameter portion 103a2 of the movable shaft 103a, and the first groove 9d1 extends in a direction in which the position pushed by the movable shaft 103a changes. It is further extended. The starting end of the second groove 9d2 is formed so as to be surrounded by a semi-cylindrical inner wall surface. The depth of the second groove 9d2 is deeper than that of the first groove 9d1, and when the actuator 103 is driven with the second protruding amount, the tip of the movable shaft 103a does not contact the bottom surface of the second groove 9d2. Is set.

  When the actuator 103 is driven with the first protrusion amount, the slide swing arm 93 swings and moves in the axial direction. In accordance with this movement, the position at which the movable shaft 103a of the actuator 103 pushes the pressing piece 9b also changes. When the slide swing arm 93 reaches the second position, it stops moving in the axial direction, and the small diameter portion 103a1 of the movable shaft 103a of the actuator 103 reaches the first groove 9d1 of the two-step recess 9d. For this reason, the small diameter portion 103a1 falls into the first groove 9d1. As a result, even if the insertion / removal pin 9a comes out of the first spiral groove 171, the side surface of the small diameter portion 103a1 is locked to the inner wall surface of the first groove 9d1, so that the slide swing arm 93 is held in the second position. Is done. Accordingly, the second link shaft 52 and the third slide arm 83 are also held in the second position. In this case, since the side surface of the small diameter portion 103a1 and the inner wall surface of the first groove 9d1 are pressed against each other by the urging force by the shaft return spring 132 and the pin return spring 77, the second position can be reliably held. It becomes.

  Further, when the actuator 103 is driven with the second protrusion amount, the slide rocking arm 93 is configured such that when the actuator 103 reaches the second position, the small diameter portion 103a1 of the movable shaft 103a of the actuator 103 is the first of the two-step recessed portion 9d. Although falling into the groove 9d1, the large-diameter portion 103a2 comes into contact with the surface of the pressing piece 9b (the plane around the first groove 9d1) and continues to press the slide rocking arm 93. Accordingly, the insertion / removal pin 9a of the slide swing arm 93 is continuously pushed and slid by the second spiral groove 172 of the spiral double step groove 170, and the slide swing arm 93 moves in the axial direction. When the slide swing arm 93 reaches the third position, the slide movement arm 93 stops its axial movement, and the large-diameter portion 103a2 of the movable shaft 103a of the actuator 103 reaches the second groove 9d2 of the two-step recess 9d. For this reason, the large diameter portion 103a2 falls into the second groove 9d2. Thereby, even if the insertion / removal pin 9a comes out of the second spiral groove 172, the side surface of the large-diameter portion 103a2 is locked to the inner wall surface of the second groove 9d2, so that the slide rocking arm 92 is in the third position. Retained. Accordingly, the second link shaft 52 and the third slide arm 83 are also held at the third position. In this case, since the side surface of the large-diameter portion 103a2 and the inner wall surface of the second groove 9d2 are pressed against each other by the urging force of the shaft return spring 132 and the pin return spring 77, the third position can be reliably held. It will be a thing.

  The connection state of the variable mechanism 40 at the first position, the second position, and the third position in the second embodiment is the same as in the first embodiment. Therefore, when the slide swing arm 93 is located at the first position, the intake valve 20 opens and closes according to the cam profile of the first cam 31. Further, when the slide swing arm 93 is located at the second position, the intake valve 20 opens and closes according to the cam profile of the second cam 32 and enters a valve resting state. When the slide swing arm 93 is positioned at the third position, the intake valve 20 opens and closes according to the cam profile of the third cam 33.

  Further, the switching timing of the first position, the second position, and the third position in the second embodiment is also performed in the same manner as in the first embodiment. That is, in the third variable mechanism 43 and the fourth variable mechanism 44, the base circle portions of the first cam 31, the second cam 32, and the third cam 33 are the first roller 611, the second roller 621, and the third roller 631, respectively. The pin array 700 of the third variable mechanism 43 and the fourth variable mechanism 44 is moved within the base circle period T1 that is in contact with the first cam 31 and the second cam in the first cylinder and the second cylinder. 32, when the base circle portion of the third cam 33 enters the base circle period T2 in contact with the first roller 611, the second roller 621, and the third roller 631, respectively, The pin array 700 of the first variable mechanism 41 and the second variable mechanism 42 is moved. Note that the starting point of the spiral groove portion in the spiral groove-shaped two-stage 170 is set to the start point of the base circle period T1 or a point immediately thereafter, and the end point of the spiral groove part is the end point of the base circle period T1. Or it is set to the point before that.

  The ECU 150 selects the first position when the internal combustion engine 10 is operated at a high load. In this case, the ECU 150 does not operate the actuator 103. Therefore, the intake valve 20 opens and closes according to the cam profile of the first cam 31 and generates torque suitable for high load operation.

  The ECU 150 selects the third position when the internal combustion engine 10 is operated at a low / medium load. For example, when switching from the first position to the third position, the ECU 150 controls the drive of the actuator 103 so that the protrusion amount becomes the second protrusion amount. In this case, the ECU 150 reads the output signal of the cam position sensor 201, and sets the rotation angle of the camshaft 30 such that the insertion / removal pin 9a of the slide swing arm 93 falls to the spiral two-step groove 170 starting end 170a or slightly forward. When detected, the actuator 103 is operated.

  The slide swing arm 93 swings by an angle corresponding to the second protrusion amount (second swing angle). Thus, the insertion / removal pin 9a is inserted into the start end portion 170a of the spiral double step groove 170 and then guided to the second spiral groove 172 by the rotation of the spiral groove forming body 160. As a result, the slide swing arm 93 slides in the axial direction on the outer peripheral surface of the rocker shaft 50 by a distance B from the first position. Therefore, the third variable mechanism 43 and the fourth variable mechanism 44 are switched to the third position, and then the first variable mechanism 41 and the second variable mechanism 42 are switched to the third position by the action of the combined delay mechanism 140. . Thereby, since the intake valve 20 opens and closes according to the cam profile of the third cam 33, the Atkinson cycle is performed, the thermal efficiency is increased, and the fuel consumption can be reduced. For this reason, it is suitable for low / medium load operation.

  The ECU 150 selects the second position when performing the fuel cut operation. For example, when switching from the first position to the second position, the ECU 150 controls the drive of the actuator 103 so that the protrusion amount becomes the first protrusion amount. Also in this case, the ECU 150 reads the output signal of the cam position sensor 201, and the rotational angle of the camshaft 30 is such that the insertion / removal pin 9a of the slide rocking arm 93 falls to the spiral double step groove 170 starting end 170a or slightly in front of it. Is detected, the actuator 103 is operated.

  The slide swing arm 93 swings by an angle corresponding to the first protrusion amount (first swing angle). Thus, the insertion / removal pin 9 a is inserted into the start end portion 170 a of the spiral double step groove 170 and then guided to the first spiral groove 171 by the rotation of the spiral groove forming body 160. As a result, the slide swing arm 93 slides in the axial direction on the outer peripheral surface of the rocker shaft 50 by the distance A from the first position. Therefore, the third variable mechanism 43 and the fourth variable mechanism 44 are switched to the second position, and then the first variable mechanism 41 and the second variable mechanism 42 are switched to the second position by the action of the combined delay mechanism 140. . As a result, the intake valve 20 opens and closes according to the cam profile of the second cam 32, and thus enters a resting state.

  Further, the ECU 150 switches from the third position to the first position when switching from the low / medium load operation to the high load operation. In this case, the ECU 150 stops energization of the actuator 103. This energization stop timing may be arbitrary regardless of the rotation angle of the camshaft 30. As a result, the movable shaft 103a of the actuator 103 comes out of the two-step recess 9d of the slide swing arm 93, and the slide swing arm 93 returns to the initial position by its own weight. As a result, the variable mechanisms 41, 42, 43, and 44 are switched from the third position to the first position on the same principle as in the first embodiment.

  Further, the ECU 150 switches from the second position to the first position when switching from the fuel cut operation to the high load operation. In this case, the ECU 150 stops energization of the actuator 103. This energization stop timing may be arbitrary regardless of the rotation angle of the camshaft 30. As a result, the movable shaft 103a of the actuator 103 comes out of the two-step recess 9d of the slide swing arm 93, and the slide swing arm 93 returns to the initial position by its own weight. As a result, the variable mechanisms 41, 42, 43, and 44 are switched from the second position to the first position on the same principle as in the first embodiment.

  Further, when switching from the fuel cut operation to the low / medium load operation, or when switching from the low / medium load operation to the fuel cut operation, the ECU 150 temporarily stops energization of the actuator 103 and returns it to the first position. Then, the actuator 103 is driven again to switch to the third position or the second position.

  As described above, the pin drive mechanism 210 of the second embodiment includes the link shafts 51 and 52, the slide arms 81, 82, and 83, the slide swing arm 93, the actuator 103, the spiral groove forming body 160, and the shaft. The return mechanism 130, the coupled delay mechanism 140, the ECU 150, and the cam position sensor 201 are configured.

  According to the variable valve operating apparatus of the present embodiment described above, the operation of the three types of cams 31, 32, 33 is selected by switching the connection state of the variable mechanism 40 by the drive control of the actuators 101, 102 (103). Therefore, the valve lift characteristic can be switched to three stages. Therefore, it is possible to control to an appropriate intake air amount according to the operating state of the internal combustion engine 10. In particular, since the Atkinson cycle can be executed during low / medium load operation, a fuel efficiency effect can be obtained. Further, during the fuel cut operation, since the valve is in a paused state, it is possible to suppress deterioration or decrease in the purification performance of the exhaust purification device.

  In addition, the switching of the connection state of the variable mechanism 40 is performed by connecting / disconnecting adjacent roller rocker arms by changing the position of the pin array 700 with respect to the pin hole array 600 formed in each roller rocker arm 61-63. In addition, since the pin hole row 600 and the pin row 700 are configured in one row, the number of parts can be reduced and the space can be saved.

  Further, as the pin drive mechanism 200 for switching the connection state of the variable mechanism 40, the slide swing arms 91 and 92 (93) are swung by the actuators 101 and 102 (103), and the insertion / removal pin 9a is inserted into the spiral grooves 112 and 122 ( 170), the operation of the pin row is better than that of the conventional device that moves the pin row by hydraulic pressure, and the connection state of the variable mechanism 40 can be switched well. Can do. Further, since a hydraulic circuit is not required, space can be saved.

  Further, since the slide swing arms 91 and 92 (93) are moved using the two spiral grooves 112 and 122 (171 and 172) having different axial lengths, the connection state of the variable mechanism 40 can be easily switched to three ways. be able to. Further, slide arms 81 and 82 (83) and slide swing arms 91 and 92 (93) for pressing the pin array 700 of the four variable mechanisms 40 are connected to the link shafts 51 and 52, and the link shaft is the first. Since the link shaft 51 and the second link shaft 52 are divided and connected by the coupled delay mechanism 140, the variable mechanisms of the remaining cylinders are switched after switching the connection state of the variable mechanisms 40 of some cylinders. 40 connected states can be automatically switched. Therefore, the connection switching control by the ECU 150 is simplified. That is, it is not necessary to separately perform switching control corresponding to a plurality of cylinders.

  Further, in the second embodiment, two spiral grooves 171 and 172 having different depths are arranged in parallel in one spiral groove forming body 160 to control the protrusion amount of the actuator 103 (the swing angle of the slide swing arm 93). In order to select the spiral grooves 171 and 172 into which the insertion / removal pin 9a is inserted, the amount of slide movement corresponding to the selected spiral grooves 171 and 172 can be obtained. Accordingly, it is possible to switch to three slide positions (first position, second position, and third position) using one spiral groove forming body 160, actuator 103, and slide swing arm 93, respectively, and the number of parts can be further increased. Can be reduced.

  In addition, since the concave portions 9c into which the movable shafts 101a and 102a of the actuators 101 and 102 fall are formed at predetermined positions on the pressing pieces 9b of the slide swing arms 91 and 92, the slides can be moved even if they come out of the insertion / removal pins 9a or the spiral grooves 112 and 122. The swing arms 91 and 92 can be reliably held at the second position or the third position. In particular, in the second embodiment, the two-step recess 9d having different depths is formed, and the slide swing arm 93 is held at a position corresponding to the protruding amount of the actuator 103 (position corresponding to the selected spiral groove). Therefore, it can be implemented with a small number of parts and a small space.

  Although the variable valve operating apparatus for an internal combustion engine according to this embodiment has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the object of the present invention.

  For example, in the present embodiment, the lift amount of the intake valve 20 is switched to three stages, but the present invention may also be applied to the exhaust valve 21 to switch the valve lift characteristics to three stages. Further, the exhaust valve 21 may be switched in two stages so that the exhaust valve 21 is also in a resting state in accordance with the resting state of the intake valve 20.

  In the present embodiment, one of the three cams 31, 32, 33 is used for zero lift (for valve stop). However, it is not always necessary to provide a zero lift cam, and three cams having a nose portion are used. The configuration may be acceptable.

  DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 20 ... Intake valve, 21 ... Exhaust valve, 25 ... Valve spring, 30 ... Intake cam shaft, 31, 32, 33 ... Cam, 41, 42, 43, 44 ... Variable mechanism, 61, 62, 63 ... Roller rocker arm, 62a ... Main arm, 62b ... Sub arm, 62c ... Connecting part, 81,82,83 ... Slide arm, 91,92,93 ... Slide rocking arm, 9a ... Inserting / removing pin, 9b ... Pressing piece , 9c ... recess, 9d ... two-step recess, 50 ... rocker shaft, 51, 52 ... link shaft, 71, 72, 73, 74, 75, 76 ... pin, 77 ... spring for pin return, 78 ... spring force transmission member 101, 102, 103 ... Actuator, 101a, 102a, 103a ... Movable shaft, 111, 121, 160 ... Spiral groove forming body, 112, 122 ... Spiral groove 112a, 122a ... start end portion, 112b, 122b ... end portion, 112c, 122c ... vertical wall surface, 130 ... shaft return mechanism, 140 ... coupled delay mechanism, 150 ... ECU, 170 ... spiral double step groove, 171 ... first spiral Groove, 172 ... second spiral groove, 170a ... start end, 171b, 172b ... end, 171c, 172c ... vertical wall surface, 171d, 172d ... bottom, 200, 210 ... pin drive mechanism, 600 ... pin hole array, 611 621, 631 ... roller, 613, 623, 624, 633 ... pin hole, 650 ... connected state switching mechanism, 700 ... pin row.

Claims (3)

In a variable valve operating apparatus for an internal combustion engine, which can select any one of three cams having different cam profiles as a valve driving cam,
Three rocker arms that transmit the actuation force of each of the three cams and swing according to each cam profile;
Inserting a pin row in which a plurality of pins are arranged in series in the three rocker arms, and switching between a state where the adjacent rocker arms are separated from each other and a state where they are connected to each other depending on the insertion position of the pin row, A connection state switching mechanism for selectively transmitting any one of the three cams to the valve;
A first spiral groove formed in a spiral on a rotating body that rotates integrally with the camshaft;
A second spiral groove formed in a spiral shape on a rotating body that rotates integrally with the camshaft, wherein the axial distance of the camshaft is longer than the first spiral groove;
Inserting / removing pins selectively into the first spiral groove and the second spiral groove, and a force that pushes the insertion / removal pin against the spiral groove by rotation of the camshaft is a pin array of the connection state switching mechanism And a pin drive mechanism that changes the insertion position of the pin row in two ways with respect to a reference position by transmitting to the variable valve system of the internal combustion engine. The first spiral groove and the second spiral groove are
The rotating body that rotates integrally with the camshaft is formed with a spiral double step groove in which two spiral grooves having different depths are arranged in common at the start end, and the shallower spiral groove is defined as the first spiral groove. The deeper spiral groove is the second spiral groove,
The pin drive mechanism is
The variable valve operating apparatus for an internal combustion engine according to claim 1, further comprising an actuator that allows the insertion / removal pin to be inserted into the spiral two-stage groove and the amount of insertion to be switched between two stages. The pin drive mechanism is
A slide rocking arm that is rockably and axially supported by a rocker shaft that rockably supports the rocker arm, and has the insertion / removal pin on the tip side;
An actuator capable of swinging the slide swing arm and switching the swing angle between two types;
The actuator is driven and controlled to swing the slide swing arm by a first swing angle so that the insertion / removal pin is inserted into the first spiral groove, and the slide swing arm is moved to the first swing angle. Actuator driving means for causing the insertion / removal pin to be inserted into the second spiral groove by oscillating by a larger second oscillating angle,
The insertion / removal pin is pushed by one spiral groove in the spiral two-stage groove, and the slide swing arm urges the pin row with a force that moves the rocker shaft in the axial direction, thereby inserting the pin row. 3. The variable valve operating apparatus for an internal combustion engine according to claim 2, wherein the position is changed by a moving distance of the slide swing arm.

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