JP2017122423A - Valve timing control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a valve timing control device which secures vibration control performance, quietness and durability in a cylinder-activation type internal combustion engine.SOLUTION: A valve timing control device comprises: a first control block 661 which controls a rotation phase to the most retardant phase Pr for moving a gravity center line Cp of a phase adjustment mechanism toward a first symmetric point Lp1 side opposite to a first gravity center position Lg1 with a rotation center line of an intake camshaft sandwiched when holding valve timing in a deactivation objective cylinder operation state that a gravity center line Cg of the intake camshaft is changed in a position to the first gravity center point Lg1; and a second control block 662 which controls the rotation phase to the most advanced phase Pa for moving the gravity center line Cp of the phase adjustment mechanism toward a second symmetric position Lp2 side opposite to a second gravity center Lg2 with the rotation center line of the intake camshaft sandwiched when holding the valve timing in a deactivation objective cylinder deactivation state that the gravity center Cg of the intake camshaft is changed in a position to a second gravity center position Lg2 which is different from the first gravity center position Lg1.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a valve timing control device for controlling valve timing in a cylinder deactivation type internal combustion engine.

  2. Description of the Related Art Conventionally, valve timing control devices that control valve timing in internal combustion engines have been widely used from the viewpoint of fuel efficiency. For example, in the valve timing control device disclosed in Patent Document 1, a phase adjustment mechanism that rotates integrally with a camshaft that is bearing in an internal combustion engine adjusts the rotational phase of the camshaft relative to the crankshaft so that the valve timing is adjusted. It is decided. In addition, in the valve timing control device disclosed in Patent Document 1, in particular, a weight adjustment unit for adjusting the center of gravity is provided in the phase adjustment mechanism, so that it is possible to balance the rotation balance in the mechanism. ing.

  In recent years, a cylinder deactivation type internal combustion engine having a deactivation target cylinder whose operation state can be switched between an operation state and a deactivation state has been attracting attention from the viewpoint of fuel efficiency. For example, in the cylinder deactivation type internal combustion engine disclosed in Patent Document 2, it is possible to switch the operation state of the deactivation target cylinder by a cylinder deactivation mechanism having a structure in which two types of cams having different profiles are provided for each cylinder. It has become.

JP 2000-27609 A JP 2011-144780 A

  Now, in the internal combustion engine disclosed in Patent Document 2, due to the structure of the cylinder deactivation mechanism that switches the operation state of the cylinder to be deactivated, a position change due to the switching occurs in the center of gravity line of the cam shaft. Therefore, in the internal combustion engine disclosed in Patent Document 2, assuming the application of the valve timing control device disclosed in Patent Document 1, the position of the center of gravity line of the cam shaft changes, so that the total of the phase adjustment mechanism and the cam shaft Rotation balance at will be lost. As a result of the rotation balance being lost, the internal combustion engine vibrates and generates abnormal noise, which deteriorates vibration damping and quietness. In addition, as a result of the loss of rotation balance, aged secular wear occurs at the bearing portion of the camshaft, thereby deteriorating durability.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a valve timing control device that ensures vibration damping, silence, and durability in a cylinder deactivation type internal combustion engine. It is in.

  The technical means of the invention for achieving the object will be described below. The reference numerals in parentheses described in the claims and in this section disclosing the technical means of the invention indicate the correspondence with the specific means described in the embodiment described in detail later. It is not intended to limit the technical scope of the invention.

The invention disclosed in order to solve the above problems
In a cylinder deactivation type internal combustion engine (1) having deactivation target cylinders (S1, S4) whose operation state is switched between an operation state and a deactivation state, the rotational phase of the cam shaft (3a) with respect to the crankshaft (2) A valve timing control device (10) for controlling a determined valve timing,
A phase adjustment mechanism (7) that rotates integrally with a camshaft that is supported in an internal combustion engine and adjusts the rotational phase;
When the valve timing is maintained in the operating state of the cylinder to be deactivated in which the center of gravity line (Cg) of the camshaft changes to the first center of gravity position (Lg1), the camshaft centerline (Cc) is sandwiched between A first control block (661) that controls the rotational phase to the first holding phase (Pr) that moves the barycentric line (Cp) of the phase adjusting mechanism toward the first symmetrical position (Lp1) opposite to the one barycentric position. )When,
When the valve timing is maintained in a paused state of a cylinder to be paused where the center of gravity line of the cam shaft changes to a second center of gravity position (Lg2) different from the first center of gravity position, the camshaft rotation center line is sandwiched. A second control block (662) for controlling the rotational phase to a second holding phase (Pa) that moves the barycentric line of the phase adjusting mechanism toward the second symmetric position (Lp2) opposite to the second barycentric position; Is provided.

  According to the present invention, when the valve timing is maintained in the operation state of the cylinder to be deactivated in which the center of gravity line of the cam shaft changes to the first center of gravity position, the rotation phase of the cam shaft with respect to the crank shaft is the first holding phase. To be controlled. Here, according to the control to the first holding phase, the barycentric line of the phase adjusting mechanism moves toward the first symmetrical position opposite to the first barycentric position across the rotation center line of the cam shaft. In this case, the midpoint position between the gravity center lines of the phase adjustment mechanism and the camshaft appears at a position superimposed on or near the rotation centerline, so that the total rotation balance of the phase adjustment mechanism and the camshaft is balanced. You can get as close as possible.

  At the same time, according to the present invention, when the valve timing is maintained in the deactivation state of the deactivation target cylinder in which the position of the center of gravity of the cam shaft changes to the second position of the center of gravity different from the position of the first center of gravity, The rotational phase of the shaft is controlled to the second holding phase. Here, according to the control to the second holding phase, the barycentric line of the phase adjusting mechanism moves toward the second symmetrical position opposite to the second barycentric position across the rotation center line of the cam shaft. Also in this case, the midpoint position between the gravity center lines of the phase adjustment mechanism and the camshaft appears at a position superimposed on or near the rotation centerline, so that the total rotation balance of the phase adjustment mechanism and the camshaft is balanced. As close as possible.

  According to the above, even if the position of the center of gravity line of the camshaft changes as the operation state of the cylinder to be deactivated is switched, the period for holding the valve timing is used in both the phase adjustment mechanism and the camshaft. Rotation can be stabilized. Therefore, by suppressing the occurrence of abnormal noise due to vibration of the cylinder deactivation type internal combustion engine, vibration suppression and quietness are ensured, and the occurrence of uneven wear at the bearing portion of the camshaft is suppressed. Thus, it is possible to ensure durability.

It is a schematic block diagram which shows the internal combustion engine and valve timing control apparatus by one Embodiment. It is a schematic block diagram which shows the internal combustion engine and valve timing control apparatus by one Embodiment, Comprising: It corresponds to the II-II arrow directional view of FIG. It is a figure which shows the valve timing control apparatus and energization control unit by one Embodiment, Comprising: It is the III-III line longitudinal cross-sectional view of FIG. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3. It is a cross-sectional view which shows the operation state different from FIG. It is the VI-VI line cross-sectional view of FIG. It is a schematic block diagram which shows the control circuit by one Embodiment in detail. It is a block diagram which shows the several block which the control circuit by one Embodiment constructs | assembles functionally.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a valve timing control device 10 according to an embodiment of the present invention is applied to an internal combustion engine 1 for a vehicle.

  As shown in FIGS. 1 and 2, the internal combustion engine 1 to which the apparatus 10 is applied includes an in-line multi-cylinder engine having a plurality of cylinders S arranged in a line along the axial direction of the crankshaft 2 and the camshafts 3a and 3b. It is. The internal combustion engine 1 of the present embodiment is a gasoline engine that burns gasoline fuel in the four cylinders S. Here, assuming that each cylinder S is S1, S2, S3, S4 in order from the lower side of FIG. 2, combustion in the internal combustion engine 1 of the present embodiment occurs in the order of S4, S2, S1, S3. Yes.

  In the internal combustion engine 1 shown in FIGS. 1 and 2, crank torque is output from the crankshaft 2 to drive the transaxle of the vehicle. At this time, crank torque is transmitted to the intake camshaft 3a through the driven rotating body 71 from the driving rotating body 70 in the phase adjusting mechanism 7 of the device 10 described in detail later. As a result, the intake camshaft 3a opens and closes an intake valve provided for each cylinder S at a variable valve timing. At this time, crank torque is transmitted to the exhaust camshaft 3b through the drive rotating body 70 in the phase adjusting mechanism 7. As a result, the exhaust camshaft 3b opens and closes an exhaust valve provided for each cylinder S at a fixed valve timing.

  In the cylinders S2 and S3 in which the combustion order is not continuous in the internal combustion engine 1, the operation state in which the intake valve and the exhaust valve are driven to open and close is always maintained. Therefore, in the following, the cylinders S2 and S3 whose operation state is maintained in the operating state are set as the operation target cylinders S2 and S3 in particular. On the other hand, in the cylinders S1 and S4 which are not continuous with each other because the combustion order is between the operation target cylinders S2 and S3, the operation state in which the intake valve and the exhaust valve are driven to open and close, and the stop to stop the opening and closing drive of both the valves The state is alternately switched by the cylinder deactivation mechanism 9 shown in FIG. Therefore, in the following, the cylinders S1 and S4 whose operation state is switched between the operation state and the inactive state are particularly set as the inactive cylinders S1 and S4.

  The cylinder deactivation mechanism 9 has a structure in which the connection realized between the camshafts 3a and 3b and both valves in the operation state of the deactivation target cylinders S1 and S4 can be cut off in the deactivation state of the deactivation target cylinders S1 and S4. Built. As the cylinder deactivation mechanism 9, various structures such as a cam slide type can be adopted as long as the center of gravity line Cg of the intake camshaft 3a changes in accordance with the switching of the operation state in the deactivation target cylinders S1 and S4. is there.

  By such a cylinder deactivation mechanism 9, during the operation period in which the operation target cylinders S2 and S3 and the deactivation target cylinders S1 and S4 are all in the operation state, the center of gravity line of the intake camshaft 3a to the first center of gravity position Lg1 shown in FIG. Cg changes its position. Here, the operating period is set, for example, when the internal combustion engine 1 is controlled in a transient state in order to accelerate the vehicle. On the other hand, in the pause period in which the cylinders S2 and S3 are in the operation state and the cylinders S1 and S4 are in the stop state by the cylinder stop mechanism 9, the positions different from the first center-of-gravity position Lg1 are shown in FIG. The center of gravity line Cg of the intake camshaft 3a changes to the second center of gravity position Lg2 shown. Here, the rest period is set, for example, when the internal combustion engine 1 is controlled in a steady state in order to cause the vehicle to travel steadily. As shown in FIG. 3, the center of gravity line Cg is an imaginary line extending substantially parallel to the rotation center line Cc of the coaxial 3a through the load center of gravity of the entire intake cam shaft 3a including the intake cam for driving the intake valve. ,is assumed.

  In the cylinder deactivation type internal combustion engine 1 as described above, the device 10 variably controls the valve timing determined by the rotation phase of the intake camshaft 3a with respect to the crankshaft 2 (hereinafter simply referred to as “rotation phase”). As a result, the valve timings of the intake valves are commonly controlled by the device 10 in each of the operation target cylinders S2 and S3 and the suspension target cylinders S1 and S4 sharing the intake camshaft 3a as shown in FIG.

  As shown in FIGS. 1 to 3 and 7, the apparatus 10 includes an electric motor 4, an energization control unit 6, and a phase adjustment mechanism 7.

  As shown in FIG. 3, the electric motor 4 is a brushless motor such as a permanent magnet type synchronous motor. The electric motor 4 includes a motor case 40, a bearing 41, a motor shaft 42, a magnetic rotor 43, a rotor magnet 44, a motor stator 45, a motor sensor 48 and a sensor magnet 49.

  The motor case 40 is fixed to a fixed node such as a chain case of the internal combustion engine 1. The motor case 40 is formed in a cylindrical shape and accommodates other components 41, 42, 43, 44, 45, 48, and 49 inside the electric motor 4. The pair of bearings 41 respectively support the motor shaft 42 so as to be able to rotate forward and backward. The magnetic rotor 43 is formed in an annular plate shape that protrudes radially outward from the motor shaft 42, and can rotate forward and backward in the circumferential direction. The magnetic rotor 43 holds a plurality of rotor magnets 44 so as to be integrally rotatable at positions spaced equidistantly in the forward and reverse rotational directions. The motor stator 45 is formed in an annular plate shape and surrounds the magnetic rotor 43 coaxially from the outside in the radial direction. The motor stator 45 is configured by combining a plurality of stator cores 46 and motor coils 47, respectively. The stator cores 46 are arranged at equal intervals in the forward and reverse rotation directions of the motor shaft 42 and the magnetic rotor 43. Each motor coil 47 is individually wound around a corresponding stator core 46 and is star-connected to each other.

  The motor sensor 48 is a rotation detection sensor in which a plurality of magnetoelectric conversion elements such as Hall elements are combined. The motor sensor 48 senses the magnetic field formed by the sensor magnet 49 held by the magnetic rotor 43 so as to rotate integrally as shown in FIGS. Thereby, the motor sensor 48 outputs a rotation detection signal based on the sensed magnetic field. Here, the rotation detection signal is a signal representing the rotation state of the motor shaft 42.

  The energization control unit 6 controls the energization of each motor coil 47 based on the operation status of the internal combustion engine 1 and the rotation state of the motor shaft 42. The electric motor 4 energizes each motor coil 47 in sequence by receiving energization controlled by the energization control unit 6. As a result, a magnetic field acting on each rotor magnet 44 is formed, so that the motor shaft 42 rotates in the forward rotation direction (that is, clockwise in FIGS. 4 and 6) or in the reverse rotation direction (that is, counterclockwise in FIGS. 4 and 6). Direction).

  As shown in FIGS. 3, 4, and 6, the phase adjustment mechanism 7 includes a drive rotator 70, a driven rotator 71, a planet carrier 72, a joint 73, a planetary bearing 74, and a planetary gear 75.

  The drive rotator 70 is formed in a cylindrical shape by screwing a plurality of members on the same axis. The drive rotator 70 accommodates the other components 71 to 75 in the phase adjustment mechanism 7 therein. As shown in FIGS. 3 and 6, the drive rotating body 70 forms a drive side internal gear 70 a having a tooth tip circle on the inner peripheral side of the root circle. The drive rotating body 70 forms a plurality of sprocket teeth 70b that project radially outward from locations spaced equidistantly in the circumferential direction as shown in FIGS. The drive rotating body 70 is linked to the crankshaft 2 by a timing chain being spanned between the sprocket teeth 70b and the crankshaft 2 of FIG. As a result, the drive rotating body 70 is rotated in a certain circumferential direction (that is, clockwise in FIGS. 4 and 6) in conjunction with the crankshaft 2 by transmitting the crank torque from the crankshaft 2 through the timing chain. .

  As shown in FIGS. 3 and 4, the driven rotating body 71 is formed in a bottomed cylindrical shape, and is fitted coaxially to the inner side in the radial direction of the driving rotating body 70. The driven rotating body 71 forms a driven side internal gear 71a having a tooth tip circle on the inner peripheral side of the root circle. The driven rotator 71 is coaxially connected to the intake camshaft 3a. Here, the intake camshaft 3a is supported by a cam journal 5 provided in the internal combustion engine 1, as shown in FIG. As a result, the driven rotator 71 rotates in a constant circumferential direction (that is, clockwise in FIG. 4) in conjunction with the intake camshaft 3a, while being retarded in the circumferential direction with respect to the drive rotator 70. And relative rotation in the advance direction. Note that the rotation direction of the intake camshaft 3 a and the rotating bodies 70 and 71 coincides with the positive rotation direction of the motor shaft 42.

  As shown in FIGS. 3, 4, and 6, the planet carrier 72 is formed in a partially eccentric cylindrical shape, and is coaxially disposed on the radially inner side of the rotating bodies 70 and 71. The planet carrier 72 is connected to the motor shaft 42 via a joint 73. As a result, the planetary carrier 72 can rotate relative to the drive-side internal gear 70a in the retarding direction and the advancing direction with respect to the driving side internal gear 70a while rotating forward and backward in the circumferential direction integrally with the motor shaft 42. It has become. The planetary carrier 72 forms an eccentric part 72a by a cylindrical outer peripheral surface that is eccentric from the rotation center line Cc substantially common to the intake camshaft 3a and the rotating bodies 70 and 71. The eccentric portion 72 a is fitted coaxially with the planetary gear 75 via the planetary bearing 74. As a result, the planetary gear 75 supported by the eccentric portion 72a is capable of planetary movement in accordance with the relative rotation of the planet carrier 72 with respect to the drive-side internal gear 70a.

  The planetary gear 75 is formed in a stepped cylindrical shape, and is arranged eccentrically with respect to the intake camshaft 3a and the rotation center line Cc of the rotating bodies 70 and 71. The planetary gear 75 forms a drive-side external gear portion 75a and a driven-side external gear portion 75b having a tooth tip circle on the outer peripheral side of the root circle. The drive side external gear portion 75a meshes with the drive side internal gear 70a so as to be capable of planetary movement. The driven side external gear portion 75b meshes with the driven side internal gear 71a so as to be capable of planetary movement.

  As described above, the phase adjustment mechanism 7 forms a planetary gear mechanism by gear-linking the crankshaft 2, the intake camshaft 3a, and the motor shaft 42 in the internal combustion engine 1. The phase adjusting mechanism 7 adjusts the rotational phase by decelerating the rotation of the motor shaft 42 in the electric motor 4 with a predetermined reduction ratio and transmitting it to the intake camshaft 3a.

  Specifically, when the motor shaft 42 rotates forward at the same speed as the intake cam shaft 3a, the planet carrier 72 does not rotate relative to the drive-side internal gear 70a. As a result, the planetary gear 75 rotates with the rotators 70 and 71 without planetary motion, so that the rotational phase is kept substantially constant. Therefore, at this time, the valve timing of the intake valve is held in the operating cylinder S while the phase adjusting mechanism 7 rotates integrally with the intake camshaft 3a.

  On the other hand, when the motor shaft 42 rotates forward at a lower speed than the intake camshaft 3a or reversely rotates with respect to the intake camshaft 3a, the planetary carrier 72 rotates relative to the drive-side internal gear 70a in the retard direction. As a result, the planetary gear 75 moves in a planetary motion and the driven rotator 71 rotates relative to the drive rotator 70 in the retarding direction, so that the rotational phase is retarded. Therefore, at this time, the phase adjustment mechanism 7 rotates integrally with the intake camshaft 3a, and the valve timing of the intake valve is retarded in the operating cylinder S.

  On the other hand, when the motor shaft 42 rotates forward at a higher speed than the intake camshaft 3a, the planet carrier 72 rotates relative to the drive side internal gear 70a in the advance direction. As a result, the planetary gear 75 moves in a planetary motion and the driven rotator 71 rotates relative to the drive rotator 70 in the advance angle direction, so that the rotation phase is advanced. Therefore, at this time, the valve timing of the intake valve is advanced in the operating cylinder S while the phase adjusting mechanism 7 rotates integrally with the intake camshaft 3a.

  As shown in FIGS. 4 and 6, the phase adjusting mechanism 7 is further provided with a stopper structure 76. The stopper structure 76 includes a stopper groove 77 and a stopper protrusion 78. The stopper groove 77 is formed in a groove shape that is recessed radially outward in the drive rotator 70. As shown in FIG. 4, the stopper groove 77 extends in an arc shape in the circumferential direction of the drive rotating body 70. An inner end face of the stopper groove 77 in the retard direction forms a most retarded stopper face 77a. On the other hand, the inner end surface of the stopper groove 77 in the advance direction forms the most advanced stopper surface 77b. The stopper protrusion 78 is formed in a fan shape that protrudes radially outward in the driven rotor 71. The stopper projection 78 is inserted into the stopper groove 77 so that it can rotate relative to the groove 77 in the retard direction and the advance direction.

  As shown in FIG. 4, the most retarded stopper surface 77 a abuts with a stopper protrusion 78 that is relatively rotated in the retarded direction in the stopper groove 77, so that the driven rotor 71 is moved in the retarded direction with respect to the drive rotor 70. Stop relative rotation. As a result, the rotational phase is mechanically restricted at the most retarded phase Pr. At this time, in the most retarded phase Pr, the barycentric line Cp of the phase adjusting mechanism 7 is located on the eccentric side where the planetary gear 75 in the same phase Pr is eccentric with respect to the rotation center line Cc of the intake camshaft 3a. Thus, during the operation period in which the center of gravity line Cg of the intake camshaft 3a changes to the first center of gravity position Lg1, the first symmetrical position Lp1 opposite to the same position Lg1 across the rotation center line Cc in the radial direction or A gravity center line Cp of the phase adjusting mechanism 7 at the most retarded angle Pr passes through the position in the vicinity thereof. As shown in FIG. 3, the center of gravity line Cp is assumed as an imaginary line that extends substantially parallel to the rotation center line Cc of the intake camshaft 3a through the load center of gravity of the entire phase adjustment mechanism 7. FIG. 4 shows an ideal state where the center of gravity line Cp passes through the first symmetrical position Lp1.

  On the other hand, as shown in FIG. 5, the most advanced stopper surface 77 b comes into contact with the stopper protrusion 78 that is relatively rotated in the advance direction in the stopper groove 77, so that the advance angle of the driven rotator 71 with respect to the drive rotator 70. Stop relative rotation in the direction. Thereby, in the most advanced angle phase Pa, the rotational phase is mechanically restricted. At this time, at the most advanced angle phase Pa, the center of gravity line Cp of the phase adjusting mechanism 7 is located on the eccentric side of the planetary gear 75 at the same phase Pr with respect to the rotation center line Cc of the intake camshaft 3a. As a result, during the rest period in which the centroid line Cg of the intake camshaft 3a changes to the second centroid position Lg2, the second symmetric position Lp2 opposite to the same position Lg2 across the rotation center line Cc in the radial direction or The gravity center line Cp of the phase adjusting mechanism 7 at the most advanced angle phase Pa passes through the position in the vicinity thereof. FIG. 5 shows an ideal state where the center of gravity line Cp passes through the second symmetric position Lp2.

(Energization control unit)
Next, the energization control unit 6 will be specifically described.

  As shown in FIGS. 1, 3, and 7, the energization control unit 6 includes a drive circuit 60 and a control circuit 66. In the present embodiment, the drive circuit 60 is disposed inside the electric motor 4 and the control circuit 66 is disposed outside the electric motor 4. For example, both the drive circuit 60 and the control circuit 66 are external to the electric motor 4. Or you may arrange | position collectively inside.

  As shown in FIG. 7, the drive circuit 60 includes an inverter circuit unit 62 and a switching drive unit 63. The inverter circuit unit 62 is a bridge circuit in which a plurality of switching elements such as field effect transistors are combined. The inverter circuit unit 62 is electrically connected to each motor coil 47 of the electric motor 4. The switching drive unit 63 is an electronic circuit such as a drive IC, for example. The switching drive unit 63 is electrically connected to the motor sensor 48, the inverter circuit unit 62, and the control circuit 66. The switching drive unit 63 drives each switching element of the inverter circuit unit 62 on and off so that the target rotation speed represented by the control signal output from the control circuit 66 is applied to the motor shaft 42. As a result, the actual rotation speed of the motor shaft 42 is controlled toward the target rotation speed by switching the motor coil 47 to be energized.

  For such a drive circuit 60, the control circuit 66 controls the energization of each motor coil 47 by the drive circuit 60. Therefore, hereinafter, controlling the energization of each motor coil 47 by the drive circuit 60 by the control circuit 66 will be described as executing the energization control of the electric motor 4.

  The control circuit 66 is an electronic circuit mainly composed of a microcomputer having a processor 67 and a memory 68. As shown in FIGS. 1 and 7, the control circuit 66 is electrically connected to a plurality of vehicle electrical components including rotation sensors Rcr and Rca and a drive circuit 60. Here, the crank rotation sensor Rcr is a rotation sensor such as an electromagnetic pickup type. The crank rotation sensor Rcr detects the rotation of the crankshaft 2 and outputs a crank angle detection signal representing the rotation angle of the crankshaft 2. The cam rotation sensor Rca is a rotation sensor such as an electromagnetic pickup type. The cam rotation sensor Rca detects the rotation of the intake cam shaft 3a and outputs a cam angle detection signal representing the rotation angle of the intake cam shaft 3a. The drive circuit 60 outputs the rotation detection signal of the motor sensor 48 via itself.

  Based on these various outputs, the control circuit 66 executes energization control (hereinafter simply referred to as “motor control”) to the electric motor 4 by the processor 67. In such motor control, the control circuit 66 executes a specific setting process. Specifically, in the setting process, the actual phase that is the current rotation phase is set based on the rotation angle represented by the detection signals received from the rotation sensors Rcr and Rca. At the same time, in the setting process, a target phase, which is a target rotational phase, is set based on the operating state of the internal combustion engine 1 represented by a signal between the vehicle electrical components. Further, in the setting process, the target rotation speed of the motor shaft 42 is set based on the set actual phase and target phase and the rotation detection signal received from the motor sensor 48 through the drive circuit 60. A control signal representing the target rotational speed set in this way is supplied from the control circuit 66 to the switching drive unit 63, whereby motor control according to the actual phase and target phase setting results is realized.

  In addition to such motor control, the control circuit 66 performs stop control for controlling the operation of the cylinder stop mechanism 9, injection control for controlling fuel injection of the internal combustion engine 1, and ignition control for controlling ignition of the internal combustion engine 1. It is executed by the processor 67. Therefore, the control circuit 66 employs an engine ECU (ie, Electronic Control Unit), and the cylinder deactivation mechanism 9 is electrically connected. Thereby, the stop control, the injection control, and the ignition control are executed together with the motor control.

  Here, in particular, the control circuit 66 of the present embodiment functionally constructs a plurality of blocks 661 and 662 shown in FIG. 8 by executing a control program stored in the memory 68 by the processor 67. Of course, at least a part of these blocks 661 and 662 may be constructed in hardware by one or a plurality of ICs. Further, the memory 68 for storing the control program for constructing the blocks 661 and 662 may be constructed by using one or a plurality of storage media such as a semiconductor memory, a magnetic medium or an optical medium.

  The first control block 661 adjusts the actual phase to the most retarded phase Pr as the “first holding phase” and holds the valve timing during the operating period in which the cylinders S1 and S4 to be stopped are controlled to be in the operating state. Sets the target phase to the same phase Pr. In other words, during the operation period in which the gravity center line Cg of the intake camshaft 3a changes to the first gravity center position Lg1, the first control block 661 sets the target phase to the most retarded phase Pr, so that the actual phase is The valve timing is maintained by adjusting to the same phase Pr. At this time, as the actual phase is adjusted to the most retarded phase Pr, the center of gravity line Cp of the phase adjusting mechanism 7 is opposite to the first center of gravity position Lg1 across the rotation center line Cc of the intake camshaft 3a. It moves toward the first symmetrical position Lp1 side. Thus, in the phase adjusting mechanism 7, the radial midpoint position Lc between the center of gravity line Cp that also moves to the eccentric side of the planetary gear 75 at the most retarded phase Pr and the center of gravity line Cg of the intake camshaft 3a is As shown in FIG. 4, it appears at a position superimposed on or near the rotation center line Cc. Therefore, the total rotational balance of the intake camshaft 3a and the phase adjustment mechanism 7 approaches the equilibrium state as much as possible. FIG. 4 shows an ideal state in which the radial midpoint position Lc appears at a position superimposed with the rotation center line Cc.

  The second control block 662 adjusts the actual phase to the most advanced angle phase Pa as the “second holding phase” and holds the valve timing during the pause period in which the cylinders S1 and S4 are paused. Sets the target phase to the same phase Pa. In other words, the second control block 662 sets the target phase to the most advanced angle phase Pa during the rest period in which the center of gravity line Cg of the intake camshaft 3a changes to the second center of gravity position Lg2. The valve timing is maintained by adjusting to the same phase Pa. At this time, as the actual phase is adjusted to the most advanced angle phase Pa, the centroid line Cp of the phase adjustment mechanism 7 is opposite to the second centroid position Lg2 across the rotation center line Cc of the intake camshaft 3a. It moves toward the second symmetrical position Lp2. Thereby, in the phase adjusting mechanism 7, the center point Lc in the radial direction between the centroid line Cp that also moves to the eccentric side of the planetary gear 75 at the most advanced angle phase Pa and the centroid line Cg of the intake camshaft 3a is obtained. As shown in FIG. 5, it appears at a position superimposed on or near the rotation center line Cc. Therefore, the total rotational balance of the intake camshaft 3a and the phase adjustment mechanism 7 approaches the equilibrium state as much as possible. FIG. 5 shows an ideal state in which the radial midpoint position Lc appears at a position superimposed with the rotation center line Cc.

(Function and effect)
The effects of the apparatus 10 described above will be described below.

  According to the apparatus 10, when the valve timing is maintained in the operating state of the cylinders S1 and S4 to be deactivated in which the gravity center line Cg of the intake camshaft 3a changes to the first gravity center position Lg1, the rotational phase is “first”. It is controlled to the most retarded phase Pr as the “holding phase”. Here, according to the control to the most retarded phase Pr, the phase adjustment mechanism 7 moves toward the first symmetrical position Lp1 opposite to the first center of gravity position Lg1 across the rotation center line Cc of the intake camshaft 3a. The center of gravity line Cp moves. In this case, since the midpoint position Lc between the gravity center lines Cp and Cg of the phase adjustment mechanism 7 and the intake camshaft 3a appears at a position superimposed on or near the rotation center line Cc, the phase adjustment mechanism 7 and the intake camshaft 3a. The total rotational balance can be as close as possible to an equilibrium state.

  At the same time, according to the apparatus 10, the valve timing is maintained in the pause state of the cylinders S1 and S4 to be paused where the gravity center line Cg of the intake camshaft 3a changes to the second gravity center position Lg2 different from the first gravity center position Lg1. In this case, the rotational phase is controlled to the most advanced angle phase Pa as the “second holding phase”. Here, according to the control to the most advanced angle phase Pa, the phase adjustment mechanism 7 moves toward the second symmetrical position Lp2 opposite to the second center of gravity position Lg2 across the rotation center line Cc of the intake camshaft 3a. The center of gravity line Cp moves. Also in this case, since the midpoint position Lc between the gravity center lines Cp and Cg of the phase adjustment mechanism 7 and the intake camshaft 3a appears at a position superimposed on or near the rotation center line Cc, the phase adjustment mechanism 7 and the intake cam The total rotational balance of the shaft 3a can approach the equilibrium state as much as possible.

  According to the above, even if the position of the center of gravity line Cg of the intake camshaft 3a changes as the operating state of the cylinders S1 and S4 to be deactivated is switched, the phase adjustment mechanism is utilized by using the period for holding the valve timing. 7 and the intake camshaft 3a can be stabilized in rotation. Therefore, by suppressing the situation where the cylinder deactivation type internal combustion engine 1 vibrates and generates abnormal noise, vibration suppression and quietness are ensured, and the cam journal 5 which is a bearing portion of the intake camshaft 3a is biased. It is also possible to ensure durability by suppressing the occurrence of wear.

  Further, in the gear mechanism that connects the crankshaft 2 and the intake camshaft 3a as the phase adjusting mechanism 7 by the device 10, when the rotational balance is lost, the gears 70a and 75 and the gears 71a and 75 are engaged at the meshing position. Secular uneven wear tends to occur. However, the phase adjustment mechanism 7 and the intake cam are controlled by the control to the most retarded phase Pr in the operation state of the inactive cylinders S1 and S4, and by the control to the most advanced angle phase Pa in the inactive state of the cylinders S1 and S4. The total rotation balance of the shaft 3a can be brought close to an equilibrium state. Therefore, it is possible to suppress the occurrence of uneven wear at the meshing locations of the gears 70a and 75 and between the gears 71a and 75, thereby contributing to ensuring durability.

  In addition, in the planetary gear mechanism having the planetary gear 75 that is eccentric from the rotation center line Cc as the phase adjustment mechanism 7 by the device 10, if the rotation balance is lost, the planetary gear 75 has a large engagement position on the eccentric side. Uneven wear is likely to occur due to the continuous action of the load. However, the phase adjustment mechanism 7 and the intake cam are controlled by the control to the most retarded phase Pr in the operation state of the inactive cylinders S1 and S4, and by the control to the most advanced angle phase Pa in the inactive state of the cylinders S1 and S4. The total rotation balance of the shaft 3a can be brought close to an equilibrium state. Therefore, it is possible to contribute to ensuring durability by suppressing the occurrence of uneven wear at the meshing location on the eccentric side of the planetary gear 75.

  In addition, according to the control to the most retarded phase Pr in the device 10, the load is biased on the eccentric side of the planetary gear 75 at the same phase Pr with respect to the rotation center line Cc. It is easy to move the center of gravity line Cp. At the same time, according to the control to the most advanced angle phase Pa in the apparatus 10, the load is also biased to the eccentric side of the planetary gear 75 at the same phase Pa with respect to the rotation center line Cc. It is easy to move the line Cp. According to these, the eccentric state of the planetary gear 75 can be effectively used to reliably bring the total rotational balance of the phase adjusting mechanism 7 and the intake camshaft 3a closer to the balanced state. Therefore, it is possible to increase the reliability of the effect of ensuring vibration damping, silence, and durability.

(Other embodiments)
Although one embodiment of the present invention has been described above, the present invention is not construed as being limited to the embodiment, and can be applied to various embodiments without departing from the gist of the present invention. it can.

  Specifically, in the first modification, a rotational phase other than the most retarded phase Pr is adopted as the “first holding phase” when the valve timing is held during the operation period in which the cylinders S1 and S4 are in the operating state. Also good. In the second modification, a rotation phase other than the most advanced angle phase Pa may be adopted as the “second holding phase” when the valve timing is held during the pause period in which the pause target cylinders S1 and S4 are in the pause state. Good.

  In the third modification, a fluid drive mechanism that adjusts the relative rotation of the driven rotor 71 with respect to the drive rotor 70 by hydraulic pressure may be employed as the phase adjustment mechanism 7. In the third modification, the control circuit 66 is constructed so as to control energization control to the hydraulic control device that applies hydraulic pressure to the fluid drive mechanism.

  In the fourth modification, the above-described embodiment may be modified and applied to the device 10 that controls the valve timing of the exhaust valve of the internal combustion engine. In the fourth modification, the phase adjustment mechanism 7 is constructed so that the driven rotor 71 is connected to the exhaust camshaft 3b.

  In the modified example 5, only one of S1 and S4 may be set as the suspension target cylinder. Alternatively, in Modification 5, in addition to or instead of at least one of S1 and S4, one of S2 and S3 may be set as a cylinder to be deactivated.

  In the modified example 6, the above-described embodiment may be modified and applied to the internal combustion engines 1 having a number of cylinders S other than four. Alternatively, in the sixth modification, the above-described embodiment may be modified and applied to a V-type engine or a horizontally opposed engine in which a pair of banks forming a plurality of cylinders S form a predetermined angle as the internal combustion engine 1. Alternatively, in the sixth modification, the above-described embodiment may be modified and applied to a diesel engine that burns light oil in each cylinder S as the internal combustion engine 1.

DESCRIPTION OF SYMBOLS 1 Internal combustion engine, 2 Crankshaft, 3a Intake camshaft, 4 Electric motor, 5 Cam journal, 6 Current supply control unit, 7 Phase adjustment mechanism, 9 Cylinder deactivation mechanism, 10 Valve timing control device, 66 Control circuit, 70a In drive side Gear, 71a Driven side internal gear, 75 planetary gear, 661 first control block, 662 second control block, Cc rotation center line, Cg centroid line, Cp centroid line, Lc midpoint position, Lg1 first centroid position, Lg2 first Double center position, Lp1 first symmetry position, Lp2 second symmetry position, Pa most advanced angle phase, Pr most retarded angle phase, S1, S4 pause symmetry cylinder

Claims (4)

In a cylinder deactivation type internal combustion engine (1) having deactivation target cylinders (S1, S4) whose operation state is switched between an operation state and a deactivation state, the rotational phase of the cam shaft (3a) with respect to the crankshaft (2) A valve timing control device (10) for controlling a determined valve timing,
A phase adjustment mechanism (7) that rotates integrally with the cam shaft that is supported in the internal combustion engine and adjusts the rotational phase;
When the valve timing is maintained in the operating state of the cylinder to be stopped where the center of gravity line (Cg) of the cam shaft changes to the first center of gravity position (Lg1), the rotation center line (Cc) of the cam shaft The rotational phase is controlled to the first holding phase (Pr) that moves the barycentric line (Cp) of the phase adjusting mechanism toward the first symmetrical position (Lp1) opposite to the first barycentric position across A first control block (661) to perform,
Rotation of the camshaft when the valve timing is maintained in a pause state of the cylinder to be paused where the centerline of the camshaft changes to a second gravity center position (Lg2) different from the first gravity center position. The rotational phase is controlled to a second holding phase (Pa) that moves the barycentric line of the phase adjusting mechanism toward the second symmetrical position (Lp2) opposite to the second barycentric position across the center line. A valve timing control device comprising a second control block (662).   The valve timing control device according to claim 1, wherein the phase adjustment mechanism is a gear mechanism that connects the crankshaft and the camshaft.   3. The valve timing control device according to claim 2, wherein the phase adjustment mechanism is a planetary gear mechanism having a planetary gear (75) that is eccentric from a rotation center line of the cam shaft. The first control block moves the barycentric line of the phase adjusting mechanism to the eccentric side of the planetary gear at the first holding phase with respect to the rotation center line of the camshaft by the control to the first holding phase. Let
The second control block moves the barycentric line of the phase adjusting mechanism to the eccentric side of the planetary gear at the second holding phase with respect to the rotation center line of the camshaft by the control to the second holding phase. The valve timing control device according to claim 3.

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