JP6156164B2 - Valve timing control system - Google Patents

Description

  The present invention relates to a valve timing control system that variably controls the valve timing of a valve that opens and closes a camshaft by torque transmission from a crankshaft in an internal combustion engine.

  Conventionally, a valve timing for controlling a phase adjustment unit that adjusts a rotational phase between a crankshaft and a camshaft and a lock unit that can lock the rotational phase at a predetermined starting phase by the cooperation of a control valve and a control circuit. Control systems are widely known.

  For example, in the system disclosed in Patent Document 1, the phase adjustment unit and the lock unit are driven by engine oil supplied as the internal combustion engine rotates. Specifically, the control valve is operated in accordance with the control command value set by the control circuit, thereby controlling the entry / exit of the engine oil necessary for driving these units. Here, the phase adjustment unit adjusts the rotational phase of the cam shaft relative to the crankshaft as engine oil enters and exits the advance chamber between the rotor that rotates in conjunction with the crankshaft and camshaft. At the same time, in the lock unit, the rotation phase is locked to the starting phase by discharging the engine oil from the lock operation chamber provided in the rotation phase unit, while the lock phase is locked by introducing the engine oil into the lock operation chamber. Is released.

  Under the configuration of each unit, a control valve having a spool that reciprocates in the axial direction is used. Thereby, the moving position of the spool is quickly controlled in accordance with the control command value set by the control circuit, so that the engine oil can be quickly put into and out of the adjustment working chamber and the lock working chamber. Therefore, the responsiveness can be improved for the variable control of the valve timing based on the adjustment of the rotation phase.

  In the system disclosed in Patent Document 1, a plurality of areas are set as areas where the spool moves. First, in the flow rate increasing region in the lock region, the engine oil is discharged from the lock operation chamber and the engine oil is introduced into the advance chamber. Here, in the flow rate increasing region where the spool is moved when the internal combustion engine is started, the advance chamber can be filled with the engine oil while the rotational phase is locked to the start phase, so that the startability of the internal combustion engine can be ensured. Become.

  Further, in the flow restriction area set on one side in the spool axis direction with respect to the flow increase area in the lock area, the engine oil is discharged from the lock operation chamber and the flow rate of the engine oil introduced into the advance chamber is It is narrower than the flow rate increase region. Here, the flow restricting region is realized, for example, at the time of system failure in which the electromagnetically driven control valve cannot normally receive power from the control circuit. In such a flow restricting region, the introduction flow rate into the advance chamber can be continuously reduced, so that adverse effects on the internal combustion engine due to continued consumption of engine oil can be suppressed.

  Furthermore, in the advance angle region on the opposite side of the flow restricting region across the flow rate increasing region in the spool axis direction, the engine oil is introduced into the lock working chamber where the discharge of the engine oil is stopped, and The engine oil introduction flow rate is controlled to a flow rate necessary for adjusting the advance angle of the rotation phase. Here, in the advance angle region in which the spool moves during the rotation of the internal combustion engine, the rotation phase can be unlocked, so that the rotation phase can be freely adjusted after the internal combustion engine is started.

JP 2012-149598 A

  However, in the disclosed system of Patent Document 1, if the correlation between the control command value and the spool movement position varies at the start of the internal combustion engine, and the spool movement position is controlled outside the flow rate increase region, the following problems are caused. There was a concern to generate.

  First, when the spool moves from the flow restricting region to the flow increasing region side and is localized, the flow rate introduced into the advance chamber is reduced, leading to poor filling of the advance chamber. During the rotation of the internal combustion engine after starting under such a poor filling condition, for example, when the lock is released by controlling the spool in the advance angle region, the rotor that receives the cam torque from the camshaft violates and the sound of the hammer There was a possibility that the silence was deteriorated by the generation of abnormal noise.

  On the other hand, when the spool moves out of the flow rate increasing region toward the advance angle region, the engine oil flows into the lock working chamber where the engine oil discharge stops from the gap in the phase adjusting unit or the regular introduction path. . As a result, when the internal combustion engine is started, the lock is released and the rotation phase deviates from the start phase, which may cause a combustion failure and deteriorate startability.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a valve timing control system that ensures quietness and startability.

  The invention disclosed in order to solve the above-described problem is a valve timing control system (1) that variably controls the valve timing of a valve that opens and closes a camshaft (2) by torque transmission from a crankshaft in an internal combustion engine. An adjustment working chamber (22) into and out of engine oil supplied with the rotation of the internal combustion engine is provided between the rotor (12, 14) that rotates in conjunction with the crankshaft and the camshaft. Includes a phase adjustment unit (11) that adjusts the rotational phase of the camshaft relative to the crankshaft in response to the entry and exit of engine oil, and a lock operation chamber (164) that is provided in the phase adjustment unit and into and out of the engine oil. When the engine oil is discharged from the chamber, the rotational phase is locked to the predetermined starting phase (Ps), while the A lock unit (16) that releases the lock by introducing the oil and a spool (70) that reciprocates in the axial direction, and controls the oil in and out of the adjustment working chamber and the lock working chamber according to the movement of the spool. And a control circuit (90) for setting a control command value (V) for controlling the movement position of the spool, and an engine oil from the lock operating chamber as a region in which the spool moves. The lock introduction region (Rli) for introducing engine oil into the adjustment working chamber and one side in the axial direction with respect to the lock introduction region are set to discharge engine oil from the lock operation chamber and to adjust the operation chamber. A lock throttle area (Rls) that throttles the flow rate of engine oil into the lock introduction area and the lock introduction area in the axial direction The engine oil is set to the opposite side of the lock throttle area, and the engine oil is introduced into the lock chamber where the engine oil discharge is stopped, and the flow rate of the engine oil introduced into the adjustment chamber is controlled to the flow required to adjust the rotation phase. The lock release region (Ra) to be set is set, and the control circuit is configured so that, at the start of the internal combustion engine, the movement position of the spool in the lock introduction region changes with time from the lock release region side to the lock throttle region side. And command value setting means (S104) for variably setting the control command value.

  When the internal combustion engine according to the present invention is started, the control command value is variably set by the control circuit, so that the spool movement position in the lock introduction region changes with time from the lock release region side to the lock throttle region side. As a result, even if the spool moves out of the lock introduction area to the lock release area where the discharge of engine oil from the lock operation chamber stops, the spool can return to the lock introduction area by moving to the lock throttle area. Therefore, even if the engine oil once flows into the lock operation chamber where the discharge is stopped, the engine oil can be reliably discharged within the lock introduction region, and the unlocking of the rotation phase can be suppressed when the internal combustion engine is started. On the other hand, the spool moves to the lock restricting area side that restricts the flow rate of introduction into the adjusting operation chamber, so that even if it is out of the lock introducing area, the spool is adjusted at the moving position on the unlocking area side before that. The introduction flow rate to the room can be secured. Therefore, even if the lock is released during the rotation of the internal combustion engine after the start, the filling failure in the adjustment working chamber can be solved to such an extent that the rampage of the rotor receiving the cam torque from the camshaft is suppressed.

  According to the invention as described above, it is possible to suppress the unlocking at the start of the internal combustion engine to ensure the startability, and to prevent the rotor from being ramped during the rotation after the start and to ensure the quietness.

  In another disclosed invention, the control command value for moving the spool to the limit position (Rlia) on the lock release area side in the lock introduction area is defined as the release side limit value (Va), and the lock introduction area If the control command value for moving the spool to the limit position (Rlis) on the lock throttle region side is defined as the throttle side limit value (Vs), the command value setting means sets the control command value to the release side limit value. After that, the control command value is changed from the release side limit value to the aperture side limit value.

  In this invention, after the spool moves to the limit position on the lock release region side in the lock introduction region by setting the control command value to the release side limit value, due to the change to the throttle side limit value of the control command value, The spool moves to the limit position on the lock throttle area side in the lock introduction area. According to this, since the time changing function of the spool moving position from the unlocking region side toward the lock restricting region side can be appropriately expressed, it is possible to exhibit the effect of ensuring silence and startability as a firm effect. .

It is a figure which shows the valve timing system by 1st embodiment, Comprising: It is the II sectional view taken on the line of FIG. It is the II-II sectional view taken on the line of FIG. It is a schematic diagram which illustrates the cam torque transmitted to the vane rotor of FIG. It is a schematic diagram which shows the characteristic of the control valve of FIG. It is sectional drawing which shows typically the operating state of the control valve of FIG. It is sectional drawing which shows typically the operation state different from FIG. It is sectional drawing which shows typically the operation state different from FIG. It is sectional drawing which shows typically the operation state different from FIGS. It is sectional drawing which shows typically the operation state different from FIGS. It is a time chart for demonstrating the starting action | operation of the valve timing system of FIG. It is a flowchart which shows the variable setting flow performed by the control circuit of FIG. It is a flowchart which shows the correction | amendment flow performed by the control circuit of FIG. It is a schematic diagram for demonstrating the correction | amendment by the correction | amendment flow of FIG.

It is a time chart for demonstrating the starting action | operation of the valve timing system by 2nd embodiment. It is a time chart for explaining starting operation of a valve timing system by a third embodiment. It is a flowchart which shows the modification of FIG. It is a flowchart which shows the modification of FIG. It is a time chart which shows the modification of FIG. It is a time chart which shows the modification of FIG. It is a time chart which shows the modification of FIG.

  Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In addition, the overlapping description may be abbreviate | omitted by attaching | subjecting the same code | symbol to the corresponding component in each embodiment. When only a part of the configuration is described in each embodiment, the configuration of the other embodiment described above can be applied to the other part of the configuration. In addition, not only combinations of configurations explicitly described in the description of each embodiment, but also the configurations of a plurality of embodiments can be partially combined even if they are not explicitly specified unless there is a problem with the combination. .

(First embodiment)
As shown in FIG. 1, a valve timing control system 1 according to a first embodiment of the present invention is mounted on an internal combustion engine of a vehicle. The system 1 variably controls the valve timing of the intake valve as the valve timing of the “valve” that opens and closes the camshaft 2 by transmission of crank torque from a crankshaft (not shown) in the internal combustion engine. The system 1 uses a rotation mechanism system as shown in FIGS. 1 and 2 in order to realize variable control of valve timing by using engine oil supplied from a pump 4 as a “supply source” to lubricate the internal combustion engine. 10 and a control system 50 and the like.

(Rotation mechanism system)
The rotation mechanism system 10 is installed in a transmission path that transmits crank torque from the crankshaft to the camshaft 2. The rotation mechanism system 10 includes a phase adjustment unit 11 in which a housing rotor 12 and a vane rotor 14 are combined.

  The housing rotor 12 is formed by fastening a rear plate 12b and a front plate 12c to both ends in the axial direction of the shoe housing 12a. The shoe housing 12 a includes a housing body 120 and a plurality of shoes 122. A substantially fan-shaped shoe 122 protrudes radially inward from the cylindrical housing body 120 at a predetermined interval in the rotational direction. A storage chamber 20 is formed between the shoes 122 adjacent to each other in the rotation direction. The rear plate 12b has a sprocket 124. The sprocket 124 is connected to the crankshaft via a timing chain (not shown). During such rotation, the engine torque is transmitted from the crankshaft to the sprocket 124 during rotation of the internal combustion engine, so that the housing rotor 12 is connected to the crankshaft. Rotate in a certain direction (clockwise in FIG. 2) in conjunction with the.

  The vane rotor 14 is coaxially accommodated in the housing rotor 12 and slidably contacts the rear plate 12b and the front plate 12c at both ends in the axial direction. The vane rotor 14 has a rotating shaft 140 and a plurality of vanes 142. The rotating shaft 140 is coaxially connected to the cam shaft 2. With this connection, the vane rotor 14 can rotate relative to the housing rotor 12 while rotating in the same direction as the housing rotor 12 (clockwise in FIG. 2) in conjunction with the camshaft 2.

  The rotating shaft 140 of the present embodiment is formed by fastening a boss 140b and a bush 140c to both axial ends of the shaft main body 140a. The boss 140b is connected to the camshaft 2 through the center hole of the rear plate 12b. The bush 140c protrudes out of the housing rotor 12 through the center hole of the front plate 12c.

  As shown in FIG. 1, the bushing 140c holds an inner peripheral end 144a of a spiral assist spring 144. The outer peripheral side end 144b of the assist spring 144 is locked by the first locking pin 126 until the rotational phase of the camshaft 2 with respect to the crankshaft reaches from the most retarded phase to the starting phase Ps. Here, since the first locking pin 126 is provided on the front plate 12c, the restoring force generated by the elastically deformed assist spring 144 is generated between the most retarded phase and the starting phase Ps (see FIGS. 5 and 6). The vane rotor 14 is biased in the advance direction by the force. On the other hand, the outer peripheral side end 144b of the assist spring 144 is locked by the second locking pin 146 until the rotation phase reaches the most advanced angle phase from the starting phase Ps. Here, since the second locking pin 146 is provided on the arm 140d that rotates integrally with the bush 140c, the biasing of the vane rotor 14 by the assist spring 144 is limited during the period from the starting phase Ps to the most advanced angle phase. The

  As shown in FIGS. 1 and 2, substantially fan-shaped vanes 142 protrude outward in the radial direction from locations spaced by a predetermined interval in the rotational direction on the rotating shaft 140. Each vane 142 is accommodated in the corresponding accommodating chamber 20, thereby partitioning the corresponding accommodating chamber 20 in the rotation direction as shown in FIG. 2. With such a partition, an advance chamber 22 as an “adjustment working chamber” is formed between each vane 142 and the retarded shoe 122, while between each vane 142 and the advanced shoe 122. A retarding angle chamber 24 is formed in the inner wall. That is, a plurality of advance chambers 22 and retard chambers 24 are provided alternately between the vane rotor 14 and the housing rotor 12 in the rotational direction.

  In the phase adjustment unit 11 having such a configuration, the rotational phase for determining the valve timing is adjusted in accordance with the entry / exit of the engine oil to / from each advance chamber 22 and each retard chamber 24. Specifically, the vane rotor 14 rotates relative to the housing rotor 12 in the advance direction by introducing the engine oil into each advance chamber 22 and discharging the engine oil from each retard chamber 24. As a result, the rotational phase is adjusted to advance, so that the valve timing is advanced. On the other hand, the vane rotor 14 rotates relative to the housing rotor 12 in the retarding direction by introducing the engine oil into each retarding chamber 24 and discharging the engine oil from each advancement chamber 22. As a result, the rotational phase of the camshaft 2 with respect to the crankshaft is retarded, and the valve timing is retarded. Furthermore, by restricting the entry / exit of the engine oil to / from each advance chamber 22 and each retard chamber 24, the relative rotation of the vane rotor 14 with respect to the housing rotor 12 does not occur due to the entry / exit. As a result, the rotation phase of the camshaft 2 with respect to the crankshaft is held and adjusted, and the valve timing is held and controlled.

  As shown in FIGS. 1 and 2, the rotation mechanism system 10 further includes a lock unit 16 including a lock operation chamber 164 and holes 166 and 168 provided in the phase adjustment unit 11 together with the lock member 160 and the biasing member 162. I have.

  The cylindrical lock member 160 is arranged eccentrically with respect to the rotary shaft 140 and is supported by a specific vane 142a so as to be reciprocally movable. The coil spring-like urging member 162 is arranged eccentrically with respect to the rotating shaft 140, and is interposed between the lock member 160 and the vane 142a so as to be elastically deformable. The urging member 162 generates a restoring force that urges the lock member 160 toward the front plate 12c.

  An annular space is always ensured between the lock member 160 and the vane 142 as the lock operation chamber 164 through which engine oil enters and exits. Due to the pressure of the engine oil introduced into the lock operating chamber 164, a driving force acts on the lock member 160 toward the rear plate 12b side opposite to the front plate 12c. The bottomed long hole-like restricting hole 166 extends along the rotation direction at a portion of the front plate 12c that is eccentric from the rotation shaft 140. The bottomed cylindrical hole-shaped lock hole 168 is formed in the front plate 12 c at a position eccentric from the rotation shaft 140, and opens to the bottom surface of the end portion in the advance direction of the restriction hole 166.

  In the lock unit 16 having such a configuration, the lock member 160 escapes from both the lock hole 168 and the restriction hole 166 by introducing engine oil into the lock operation chamber 164 (see FIGS. 7 to 9). As a result, the rotation phase is unlocked, and the rotation phase can be adjusted by the phase adjustment unit 11, and thus the valve timing can be variably controlled. On the other hand, when the engine oil is discharged from the lock operation chamber 164 in a state where the rotation phase is adjusted to a predetermined regulation phase range between the most retarded angle phase and the most advanced angle phase, the lock member 160 is moved to the biasing member 162. It receives the restoring force and enters the restriction hole 166 (see FIG. 1). As a result, the rotation phase is regulated within the regulation phase range. Further, when the rotational phase reaches the starting phase Ps that is a predetermined intermediate phase in the restricted phase range under such a restricted state, the lock member 160 receives the restoring force of the biasing member 162 and is fitted into the lock hole 168 ( (See FIGS. 5 and 6). As a result, the rotational phase is locked at the starting phase Ps. Here, the restriction phase range is set to a rotation phase range that allows the start of the internal combustion engine, and the start phase Ps is set to a rotation phase particularly suitable for startability within the range.

(Control system)
The control system 50 controls the entry / exit of engine oil to / from the chambers 22, 24, 164 in order to drive the rotation mechanism system 10. 1 and 2, the control system 50 includes an advance main passage 51, an advance branch passage 52, a retard main passage 53, a retard branch passage 54, a lock passage 55, a main supply passage 56, and a sub supply passage 57. , A drain recovery passage 58, a control valve 60 and a control circuit 90 are provided.

  The advance main passage 51 is formed along the inner periphery of the rotating shaft 140. The advance branch passage 52 is formed through the rotary shaft 140 and communicates with each advance chamber 22 and the advance main passage 51. The retard main passage 53 is formed along the inner peripheral portion of the rotating shaft 140. The retard branch passage 54 is formed through the rotation shaft 140 and communicates with each retard chamber 24 and the retard main passage 53. The lock passage 55 is formed through the rotary shaft 140 and communicates with the lock working chamber 164.

  The main supply passage 56 is formed through the rotary shaft 140 and communicates with the pump 4 through the lubrication passage 6 and the conveyance passage 3 shown in FIG. Here, the pump 4 is a mechanical pump that is driven by receiving crank torque from the crankshaft as the internal combustion engine rotates, and continuously discharges engine oil sucked from the drain pan 5 during the rotation. Further, the lubrication passage 6 communicates with the discharge port of the pump 4 so that the engine oil is conveyed to a location where lubrication is necessary in the internal combustion engine. Furthermore, the conveyance path 3 branched from the lubrication path 6 and penetrating the camshaft 2 conveys engine oil diverted from the path 6 to the main supply path 56. From the above, during the rotation until the internal combustion engine is started and stopped, the engine oil is supplied from the pump 4 to the main supply passage 56 through the passages 6 and 3, while the internal combustion engine is stopped and started next time. In the meantime, the supply will stop.

  As shown in FIGS. 1 and 2, the auxiliary supply passage 57 is formed through the rotary shaft 140 in a form branched from the main supply passage 56. The sub supply passage 57 receives the engine oil supplied from the pump 4 through the main supply passage 56. As shown in FIG. 1, a reed check valve 57a, a midway portion of the sub supply passage 57 and a midway portion of the main supply passage 56 on the side of the pump 4 with respect to the branch portion of the sub supply passage 57 are provided. 56a is provided (see also FIGS. 5 to 9). Here, the sub check valve 57a prevents the engine oil from flowing back to the main supply passage 56 side in the sub supply passage 57, and the main check valve 56a supplies the engine oil to the pump 4 in the main supply passage 56. Prevent backflow to the side.

  The drain collection passage 58 is provided outside the rotation mechanism system 10 and the cam shaft 2. A drain collection passage 58 opened to the atmosphere together with the drain pan 5 serving as a drain collection unit can discharge engine oil toward the drain pan 5.

  As shown in FIGS. 1 and 2, the control valve 60 uses a restoring force generated by elastic deformation of the elastic member 80 and a spool 70 that reciprocates in the axial direction using a driving force generated by energizing the driving source 82. , A spool valve provided in the sleeve 66. The control valve 60 is provided with an advance port 661, a retard port 662, a lock port 663, a main supply port 664, a sub supply port 665, and a drain port 666. Here, the advance port 661 communicates with the advance main passage 51, the retard port 662 communicates with the retard main passage 53, and the lock port 663 communicates with the lock passage 55. The main supply port 664 communicates with the main supply passage 56, the sub supply port 665 communicates with the sub supply passage 57, and the pair of drain ports 666 communicate with the drain recovery passage 58. The control valve 60 switches the connection state between these ports 661, 662, 663, 664, 665, 666 according to the movement of the spool 70. By such switching, the control valve 60 individually controls the entry / exit of the engine oil to / from the chambers 22, 24, 164.

  The control circuit 90 is an electronic circuit mainly composed of a microcomputer, for example, and is electrically connected to the drive source 82 and various electrical components (not shown) of the internal combustion engine. The control circuit 90 controls the rotation of the internal combustion engine including energization to the drive source 82 in accordance with a computer program stored in the internal memory 90a.

(Cam torque)
Next, the cam torque transmitted from the cam shaft 2 to the vane rotor 14 will be described in detail. During the rotation of the internal combustion engine, cam torque generated in the camshaft 2 due to the spring reaction force from the intake valve is transmitted to the vane rotor 14. As illustrated in FIG. 3, the cam torque alternates between a negative torque acting on the housing rotor 12 in the advance direction and a positive torque acting on the housing rotor 12 in the retard direction.

  Regarding the cam torque of the present embodiment, the peak torque Ct + of the positive torque is larger than the peak torque Ct− of the negative torque due to friction between the camshaft 2 and its support bearing, and the average torque Ctave thereof. Is biased toward the positive torque side. Therefore, the vane rotor 14 that receives cam torque at any time during the rotation of the internal combustion engine is biased on the average in the retard direction with respect to the housing rotor 12. However, the assist torque generated in the vane rotor 14 by the restoring force of the assist spring 144 is set to be larger than the average torque Ctave that gives such bias.

(Detailed structure of control valve)
Next, the structure of the control valve 60 will be described in detail.

  In the control valve 60 shown in FIG. 1, the cylindrical sleeve 66 is coaxially built in the vane rotor 14 so as to straddle the rotation shaft 140 and the cam shaft 2, and can rotate integrally with the elements 14 and 2. Is arranged. A screw portion 66 a on the bottom end side of the sleeve 66 is screwed coaxially with the cam shaft 2. The flange portion 66 b on the opening end side of the sleeve 66 sandwiches the rotary shaft 140 between the cam shaft 2 and connects the vane rotor 14 to the cam shaft 2. The sleeve 66 has a drain port 666, an advance port 661, a main supply port 664, a retard port 662, a lock port 663, an auxiliary supply port 665, and the other drain port 666 from the flange portion 66b side to the screw portion 66a side. Have in this order.

  In the control valve 60, the cylindrical spool 70 is coaxially accommodated in the sleeve 66, so that it can be rotated integrally with the vane rotor 14 and the camshaft 2. The spool 70 is slidably supported by the inner peripheral surface of the sleeve 66, so that the spool 70 can reciprocate in the forward direction Dg (right direction in FIG. 1) and the backward direction Dr (left direction in FIG. 1) in the axial direction. It has become. As shown in FIGS. 5 to 9, the spool 70 has a communication passage 705 formed in a cylindrical hole shape so as to extend the central portion in the radial direction in the axial direction. The communication passage 705 opens to the outside at both axial ends of the spool 70 so that it can communicate with both drain ports 666 regardless of the movement position of the spool 70. At the same time, the communication passage 705 opens to the outside even at the axially intermediate portion of the spool 70, so that it can communicate with at least one of the retard port 662 and the lock port 663 according to the moving position of the spool 70. Yes. Furthermore, the spool 70 has a throttle portion 704 for reducing the amount of engine oil flowing between the advance port 661 and the main supply port 664 at a predetermined movement position shown in FIG.

  Under such a configuration, the area where the spool 70 moves includes a plurality of areas Rli, Rls, Ra, Rh so that the connection states between the ports 661, 662, 663, 664, 665, and 666 are different as shown in FIG. , Rr are set.

  Specifically, in the lock introduction region Rli of FIG. 4, the advance port 661 is connected to the main supply port 664 as shown in FIG. 5. With this connection, the engine oil supplied from the pump 4 to the passages 6, 3, 56 is introduced into each advance chamber 22 through the ports 664, 661 and the passages 52, 51. At the same time, the retard port 662 is connected to each drain port 666 via the passage 705 in the lock introduction region Rli. With this connection, engine oil is sequentially discharged from each retarded angle chamber 24 to the passage 58 and the drain pan 5 through the passages 53 and 54 and the ports 662 and 666. Further, in the lock introduction region Rli, the lock port 663 is connected to each drain port 666 via the passage 705. With this connection, engine oil is sequentially discharged from the lock working chamber 164 to the passage 58 and the drain pan 5 through the passage 55 and the ports 663 and 666.

  4 is set on one side in the axial direction with respect to the lock introduction region Rli, so that the moving end of the spool 70 in the same direction Dr is located in the backward direction Dr with respect to the lock introduction region Rli. It prescribes. As shown in FIG. 6, in the lock throttle region Rls, the connection state between the ports 661, 662, 663, 664, 665, and 666 is the same as that in the lock introduction region Rli. However, in the lock throttle region Rls, the flow rate of the engine oil into each advance chamber 22 is throttled from the lock introduction region Rli according to the flow area between the ports 661 and 664 shown in FIG. . In other words, in the lock introduction region Rli, the introduction flow rate into each advance chamber 22 is larger than that in the lock restriction region Rls. Here, particularly in the present embodiment, the introduction flow rate into each advance chamber 22 increases gradually and gradually as it moves away from the lock restriction region Rls in the forward direction Dg within the lock introduction region Rli.

  The advance angle region Ra in FIG. 4 is set as an “unlock region” opposite to the lock throttle region Rls across the lock introduction region Rli in the axial direction, so that the advance direction Dg is more forward than the lock introduction region Rli. positioned. As shown in FIG. 7, the advance port 661 is connected to the main supply port 664 in the advance region Ra. With this connection, the engine oil supplied from the pump 4 to the passages 6, 3, 56 is introduced into each advance chamber 22 through the ports 664, 661 and the passages 52, 51. At this time, the flow rate of the engine oil introduced into each advance chamber 22 is controlled to a flow rate required for the advance adjustment of the rotational phase for advance control of the valve timing. At the same time, in the advance angle region Ra, the retard port 662 is connected to each drain port 666 via the passage 705. With this connection, engine oil is sequentially discharged from each retarded angle chamber 24 to the passage 58 and the drain pan 5 through the passages 53 and 54 and the ports 662 and 666. Further, in the advance angle region Ra, the lock port 663 is connected to the sub supply port 665. With this connection, the engine oil supplied from the pump 4 to the passages 6, 3, 56, 57 is introduced into the lock working chamber 164 through the ports 665, 663 and the passage 55.

  The holding region Rh in FIG. 4 is positioned on the opposite side of the lock introduction region Rli across the advance angle region Ra in the axial direction, thereby being positioned in the forward direction Dg with respect to the advance angle region Ra. As shown in FIG. 8, in the holding region Rh, the advance port 661 and the retard port 662 are blocked from any other ports. Such shut-off restricts entry / exit of the engine with respect to each advance chamber 22 and each retard chamber 24. At the same time, in the holding region Rh, the lock port 663 is connected to the sub supply port 665. With this connection, the engine oil supplied from the pump 4 to the passages 6, 3, 56, and 57 is introduced through the ports 665 and 663 and the passage 55 into the lock working chamber 164 where the discharge of the engine oil is stopped.

  The retarded angle region Rr in FIG. 4 is positioned on the opposite side of the advanced angle region Ra across the holding region Rh in the axial direction, thereby being positioned in the forward direction Dg with respect to the holding region Rh. As shown in FIG. 9, in the retard angle region Rr, the advance port 661 is connected to each drain port 666 via the passage 705. With this connection, engine oil is sequentially discharged from each advance chamber 22 to the passage 58 drain pan 5 through the passages 51 and 52 and the ports 661 and 666. At the same time, the retard port 662 is connected to the main supply port 664 in the retard region Rr. With this connection, the engine oil supplied from the pump 4 to the passages 6, 3, 56 is introduced into each retardation chamber 24 through the ports 664, 662 and the passages 54, 53. Further, in the retardation region Rr, the lock port 663 is connected to the sub supply port 665. With this connection configuration, the engine oil supplied from the pump 4 to the passages 6, 3, 56, 57 is introduced into the lock working chamber 164 through the ports 665, 663 and the passage 55.

  In order to control the movement of the spool 70 to each region Rli, Rls, Ra, Rh, Rr as described above, the control valve 60 is provided with an elastic member 80 and a drive source 82 as shown in FIG. .

  The coil spring-like elastic member 80 is accommodated coaxially in the sleeve 66. The elastic member 80 is interposed between the bottom end portion of the sleeve 66 and one end portion of the spool 70 so as to be elastically deformable. The elastic member 80 generates a restoring force that urges the spool 70 in the backward direction Dr.

  The drive source 82 is fixed to a fixed node (not shown) such as a chain cover in the internal combustion engine. In this embodiment, the drive source 82 is an electromagnetic solenoid, and controls the movement position of the spool 70 upon receiving power from the control circuit 90. Here, the drive source 82 has a rod-shaped drive shaft 82a. The drive shaft 82a is disposed coaxially with the elements 70 and 66 on the opposite side of the bottom end portion of the sleeve 66 with the spool 70 in the axial direction. As shown in FIGS. 5 to 9, the drive shaft 82 a enters into one drain port 666 formed by the opening of the sleeve 66 and always abuts against the other end of the spool 70. Under this contact state, the control circuit 90 energizes a solenoid coil (not shown) of the drive source 82, so that the driving force in the forward direction Dg according to the energized current acts on the drive shaft 82a.

  The movement of the spool 70 to each region Rli, Rls, Ra, Rh, Rr is realized by balancing the restoring force and the driving force generated by the elastic member 80 and the driving source 82, respectively. Here, particularly in the present embodiment, when the driving force generated by the driving source 82 disappears when the energization current from the control circuit 90 becomes zero, the spool 70 that receives the restoring force in the backward direction Dr from the elastic member 80 is It reaches the moving end in the same direction Dr. Therefore, in addition to the zero point control in which the control circuit 90 controls the energization current to the drive source 82 to zero, the lock that defines the moving end in the backward direction Dr at the time of system failure when the drive source 82 cannot receive the energization current normally. The spool 70 moves to the aperture region Rls.

(Operation)
Next, the overall operation of the system 1 will be described in detail.

(1) Normal operation During the rotation of the internal combustion engine after a complete explosion at the start, for example, a control command value V (see FIG. 10) such as a duty value that determines the energization current is used to control the movement position of the spool 70. Set by the control circuit 90. Further, the control circuit 90 gives an energization current according to the set control command value V to the drive source 82, so that any one of the advance angle region Ra in FIG. 7, the holding region Rh in FIG. 8, and the retard angle region Rr in FIG. Until the spool 70 is moved. As a result, in normal operation, any one of advance angle control, hold control, and retard angle control is realized as the variable control of the valve timing while the rotational phase lock is released.

(2) Fail-safe operation A system failure such as a disconnection between the control circuit 90 and the drive source 82 occurs during rotation of the internal combustion engine after a complete explosion at the start, and an energization current from the control circuit 80 to the drive source 82 When becomes zero, the spool 70 moves to the lock throttle region Rls in FIG. As a result, the engine oil is introduced into each advance chamber 22 while being squeezed, and the engine oil is discharged from each retard chamber 24 and the lock operation chamber 164. Under this entering / exiting state, when the rotational phase enters the regulation phase range due to the action of the assist torque of the assist spring 144 and the cam torque from the cam shaft 2, the lock member 160 first enters the regulation hole 166 to regulate the rotational phase. By doing so, it becomes easy to fit into the lock hole 168. Therefore, at the time of system failure, it is possible to lock the rotation phase to the starting phase Ps by such fail-safe operation.

(3) Stop operation As the internal combustion engine stops rotating due to a stop command such as an off operation of an engine switch (not shown) provided in the vehicle, the control circuit 90 reduces the energization current to the drive source 82 to zero. The control command value V is set so that As a result, the spool 70 moves to the lock aperture region Rls in FIG. In such a stop operation, the rotation phase can be locked at the start phase Ps in a short time until the rotation of the internal combustion engine is completely stopped based on the same principle as the fail-safe operation (2).

  The setting of the control command value V according to the stop operation may be adopted in the normal operation (1).

(4) Start-up operation As the internal combustion engine is cranked by a start command such as turning on an engine switch, the control circuit 90 sets the control command value V to the drive source 82 as shown in FIG. Control energizing current. As a result, the spool 70 moves to the lock introduction region Rli in FIG. 5, so that the engine oil is introduced into each advance chamber 22 at a relatively large flow rate, while the retard chamber 24 and the lock operation chamber 164 start from the engine. The oil enters and exits.

  Even in the starting operation after the internal combustion engine is stopped without the rotation phase being locked due to the engine stall or the like, the engine oil is introduced into each advance chamber 22 and the engine from each retard chamber 24 and the lock operation chamber 164. The oil enters and exits. Therefore, the rotation phase can be locked at the start phase Ps in a short time until the internal combustion engine is started based on the same principle as the fail-safe operation of (2) above.

  Here, in order to properly realize the above-described entry / exit state, in the starting operation of the present embodiment, the control circuit 90 executes the computer program stored in the internal memory 90a, whereby the variable setting flow shown in FIG. 11 is performed. The This variable setting flow is started when the engine switch is turned on.

  Specifically, in S101 of the variable setting flow, it is determined whether or not the rotational speed S of the internal combustion engine has become equal to or higher than a predetermined start determination speed Sth as shown in FIG. Here, the start determination speed Sth is a reference speed for determining that the cranking of the internal combustion engine has started normally, and is set to 400 rpm, for example. Therefore, while a negative determination is made based on the start determination speed Sth, S101 is repeatedly executed as shown in FIG. 11, whereas when an affirmative determination is made, the process proceeds to S102.

  In S102, it is determined whether or not the pressure of the engine oil supplied from the pump 4 is equal to or higher than the start determination pressure. Here, the pressure of the engine oil may be directly measured using a vehicle oil pressure sensor (not shown), or may be indirectly estimated based on, for example, the rotational speed of the internal combustion engine or the pump 4. . The start determination pressure is a reference speed for determining that the supply of engine oil has been normally started by cranking of the internal combustion engine, and is set to 100 kPa, for example. Therefore, when a negative determination is made based on the start determination pressure, the process returns to S101, whereas when an affirmative determination is made, the process proceeds to S103.

  Note that the determinations in S101 and S102 correspond to the start determination in FIG. 10, and in the present embodiment, the control circuit 90 sets the control command value V to a later-described release side limit value Va between the start command and the start determination. It is supposed to hold on.

  As shown in FIG. 11, in S103, the measured value of the control timer T is initialized to control the filling time Tf, and the increment of the measured value is started. Here, the filling time Tf is the time required to fill each advance chamber 22 with the oil after the pressure of the engine oil supplied from the pump 4 reaches the start determination pressure. The time is set to 2 to 3 seconds at room temperature, for example.

  In S104 subsequent to S103, the movement position of the spool 70 in the lock introduction area Rli is moved from the advance angle area Ra as the “lock release area” toward the lock throttle area Rls as shown in FIG. The control command value V is variably set so as to change with time. Specifically, after the control command value V is once set to the release side limit value Va in FIG. 10, the command value V is gradually and continuously changed to the aperture side limit value Vs in FIG.

  Here, the release side limit value Va is the limit position on the advance angle region Ra side where the flow rate introduced into each advance chamber 22 is maximum in the lock introduction region Rli according to the flow area between the ports 661 and 664 shown in FIG. This is a control command value V for moving the spool 70 to Rlia. The release side limit value Va is stored in the internal memory 90a. In particular, the initial value of the release side limit value Va is set to a value corresponding to the limit position Rlia set in consideration of the correlation variation between the control command value V and the movement position of the spool 70, for example, at the time of factory shipment. Is stored in the internal memory 90a.

  On the other hand, the throttle side limit value Vs is a limit on the lock throttle region Rls side that is the minimum in the lock introduction region Rli indicated by the flow rate introduced into each advance chamber 22 according to the flow area between the ports 661 and 664 shown in FIG. This is a control command value V for moving the spool 70 to the position Rlis. The aperture limit value Vs is stored in the internal memory 90a. In particular, the initial value of the aperture side limit value Vs is set to a value corresponding to the limit position Rli set in consideration of the correlation variation between the control command value V and the movement position of the spool 70, for example, at the time of factory shipment. Is stored in the internal memory 90a.

  Further, the gradual change period Tc of FIG. 10 in which the control command value V set to the release side limit value Va is gradually changed toward the throttle side limit value Vs is set to a time substantially equal to the filling time Tf in this embodiment. Is done. The rate of change per unit time of the control command value V during the gradual change period Tc may be constant regardless of the passage of time as shown in FIG. May be. Such S104 ends when the measured value of the control timer T reaches the filling time Tf, and the variable setting flow ends accordingly.

  In the starting operation of the present embodiment, the control circuit 90 executes the computer program stored in the internal memory 90a during the execution of such a variable setting flow, whereby the correction flow shown in FIG. 12 is performed. This correction flow is started together with the execution of S103 in the variable setting flow.

  In S201 of the correction flow, it is determined whether the variable setting of the control command value V is continuing or has ended. Specifically, when the measured value of the control timer T has not reached the filling time Tf, it is determined that the variable setting is continuing and the process proceeds to S202, while the measured value of the control timer T is If the filling time Tf has been reached, it is determined that the variable setting has been completed, and the process proceeds to S204.

  First, in S202 during which variable setting is continued, it is determined whether or not a deviation of the rotational phase from the starting phase Ps has occurred. Specifically, the deviation from the starting phase Ps is determined depending on whether or not the rotational phase is out of a predetermined range that can be simulated with the starting phase Ps, in particular in the present embodiment, within the error range in the advance direction from the starting phase Ps. Determine if it occurs. As a result, when a negative determination is made, the process returns to S201, whereas when an affirmative determination is made, the process proceeds to S203.

  In S203, the release side limit value Va stored in the internal memory 90a is corrected from the current value to the aperture side limit value Vs stored in the memory 90a to a value Vac that approaches the predetermined amount Δa of FIG. Here, the correction amount Δa for bringing the release side limit value Va close to the aperture side limit value Vs is set to a value sufficiently smaller than the difference between the initial values of the release side limit value Va and the aperture side limit value Vs. . Such S203 ends when the release-side limit value Va stored in the internal memory 90a is updated with the corrected value Vac, and the process returns to S201 as shown in FIG.

  In S204 after the variable setting is completed with respect to the above S202 and S203, it is determined whether or not to start the vibration determination of the rotational phase after starting the internal combustion engine. Specifically, for example, until the normal operation for unlocking the rotational phase is started by depressing the accelerator pedal in the vehicle, the negative determination is made and S204 is repeatedly executed. When started, an affirmative determination is made and the process proceeds to S205.

  In S205, it is determined whether or not it is during the determination period for determining the vibration of the rotational phase. Specifically, if the measured value of the control timer T after the end of the previous S204 is within the time required for the vibration determination of the rotational phase, an affirmative determination is made and the process proceeds to S206. Here, the time required for vibration determination, that is, the length of the determination period is set to 4 seconds, for example.

  Thus, in S206 that moves from S205, it is determined whether or not vibration of the rotational phase has occurred. Specifically, during rotation of the internal combustion engine whose rotational phase is unlocked by normal operation after startup, the vane rotor 14 is rotated at an amplitude exceeding a predetermined range in which abnormal noise such as hammering can be suppressed. It is determined whether or not the phase is oscillating. As a result, when a negative determination is made, the process returns to S205, whereas when an affirmative determination is made, the process proceeds to S207.

  In S207, the diaphragm side limit value Vs stored in the internal memory 90a is corrected from the current value to the value Vsc approaching the release side limit value Va stored in the memory 90a by a predetermined amount Δs in FIG. Here, the correction amount Δs that brings the aperture-side limit value Vs closer to the release-side limit value Va is sufficiently smaller than the difference between the initial values of the release-side limit value Va and the aperture-side limit value Vs, and S203 Is set to a value that is different or equal to the correction amount Δa. Such S207 ends when the aperture limit value Vs stored in the internal memory 90a is updated with the corrected value Vsc, and the process returns to S205 as shown in FIG. When a negative determination is made in S205, that is, when the determination period is ended, the correction flow is also ended.

  From the above, the control circuit 90 that executes S104 of the variable setting flow corresponds to “command value setting means”, and the control circuit 90 that executes S201 of the correction flow corresponds to “continuation determination means”. Further, the control circuit 90 that executes S202 of the correction flow corresponds to the “phase shift determination unit”, and the control circuit 90 that executes S203 of the correction flow corresponds to the “release side correction unit”. Furthermore, the control circuit 90 that executes S206 of the correction flow corresponds to “phase vibration determination means”, and the control circuit 90 that executes S207 of the correction flow corresponds to “aperture-side correction means”.

(Function and effect)
The operational effects of the first embodiment described so far will be described below.

  When the internal combustion engine is started, the control command value V is variably set by the control circuit 90, so that the moving position of the spool 70 in the lock introduction region Rli changes with time from the advance angle region Ra side to the lock throttle region Rls side. To do. As a result, even if the spool 70 moves out of the lock introduction region Rli toward the advance angle region Ra where the discharge of the engine oil from the lock operation chamber 164 stops, the spool 70 moves into the lock introduction region Rli by moving toward the lock throttle region Rls. You can go back to Therefore, even if the engine oil once flows into the lock operation chamber 164 whose discharge is stopped, the engine oil can be reliably discharged within the lock introduction region Rli, and the unlocking of the rotational phase can be suppressed when the internal combustion engine is started. On the other hand, the spool 70 moves to the lock restricting region Rls side that restricts the introduction flow rate into each advance chamber 22, so that even if the spool 70 is out of the lock introduction region Rli, the spool 70 moves on the advance angle region Ra side before that. The introduction flow rate to each advance chamber 22 can be secured at the position. Therefore, even if the lock is released during the rotation of the internal combustion engine after starting, the filling failure in each advance chamber 22 can be eliminated to such an extent that the rampage of the vane rotor 14 receiving the cam torque from the camshaft 2 is suppressed.

  According to the first embodiment as described above, it is possible to prevent the unlocking at the start of the internal combustion engine to ensure the startability, and to suppress the rampage of the vane rotor 14 during the rotation after the start to ensure the quietness. It becomes possible.

  Further, after the spool 70 moves to the limit position Rlia on the advance angle region Ra side in the lock introduction region Rli by setting the control command value V to the release side limit value Va, the throttle side limit value of the command value V is set. Due to the change up to Vs, the spool 70 moves to the limit position Rlis on the lock throttle region Rls side in the region Rli. According to this, since the time changing function of the spool moving position from the advance angle region Ra side toward the lock throttle region Rls side can be appropriately expressed, it is possible to exhibit the effect of ensuring quietness and startability as a firm effect.

  Further, by gradually changing the control command value V set to the release side limit value Va toward the throttle side limit value Vs, the spool 70 can be moved continuously. According to this, it is possible to suppress an abrupt change of the moving position of the spool 70 in accordance with the throttle side limit value Vs toward the lock throttle region Rls, and to make the introduction flow rate ensured for each advance chamber 22 as much as possible. Can be increased. Therefore, it is possible to improve the reliability with respect to the effect of ensuring quietness.

  Furthermore, according to the setting of the control command value V to the release side limit value Va, the limit position Rlia on the advance angle region Ra side where the introduction flow rate of the engine oil to each advance chamber 22 becomes maximum in the lock introduction region Rli. The spool 70 can be moved to According to this, since the introduction flow rate ensured for each advance chamber 22 can be increased to the maximum, it is possible to greatly contribute to enhancing the reliability of the effect of ensuring silence.

  In addition, when a rotational phase shift from the starting phase Ps occurs while the control command value V is variably set, the movement position of the spool 70 corresponding to the release side limit value Va is locked as shown by the white circle in FIG. It is predicted that the position is shifted from the limit position Rlia in the region Rli toward the advance angle region Ra. However, in this case, the release side limit value Va is corrected to the value Vac that approaches the aperture side limit value Vs from the current value, so that the movement position of the spool 70 according to the corrected release side limit value Vac is determined. As shown by the black circles in FIG. 13, it can be returned to the limit position Rlia in the lock introduction region Rli. According to this, even if the correlation between the control command value V and the movement position of the spool 70 varies over time, when the internal combustion engine is started, the correlation after the variation is learned to move the spool 70. The position can be stored in the lock introduction region Rli. Therefore, the startability ensuring effect can be exhibited over a long period of time.

  In addition, when the vane rotor 14 receiving the cam torque from the camshaft 2 is violated after the variable setting of the control command value V ends, and the vibration of the rotation phase occurs, the moving position of the spool 70 according to the throttle side limit value Vs is As indicated by the white circles in FIG. 13, it is predicted that the limit position Rli in the lock introduction area Rli is deviated toward the lock aperture area Rls. However, in this case, the throttle-side limit value Vs is corrected to a value Vsc that approaches the release-side limit value Va from the current value, so that the movement position of the spool 70 corresponding to the corrected throttle-side limit value Vsc is changed. As shown in a black circle in FIG. 13, the limit position Rli in the lock introduction region Rli can be returned. According to this, even if the correlation between the control command value V and the movement position of the spool 70 varies over time, when the internal combustion engine is started, the correlation after the variation is learned to move the spool 70. The position can be stored in the lock introduction region Rli. Therefore, it becomes possible to exhibit the effect of ensuring quietness over a long period of time.

(Second embodiment)
The second embodiment of the present invention is a modification of the first embodiment. In S104 of the variable setting flow according to the second embodiment, as shown in FIG. 14, after setting the control command value V to the release side limit value Va and holding it for a predetermined period Th, from the release side limit value Va to the aperture side. The control command value V is continuously and gradually changed to the limit value Vs.

  Here, the holding period Th for holding the control command value V is within a range smaller than the filling time Tf, even if the moving position of the spool 70 corresponding to the release side limit value Va is temporarily out of the lock introduction region Rli. It is set to a time during which unlocking can be suppressed. On the other hand, the gradual change period Tc in which the control command value V is gradually changed toward the throttle side limit value Vs is set to a time obtained by subtracting the holding period Th from the filling time Tf in the present embodiment. Also in the gradual change period Tc, the change rate per unit time of the control command value V may be constant regardless of the passage of time as shown in FIG. May be.

  The control command value V can be varied so that the moving position of the spool 70 changes over time in the lock introduction region Rli from the advance angle region Ra side to the lock throttle region Rls side also by the gradual change after the holding described above. Can be set.

  In particular, in the holding period Th in which the control command value V is set to the release-side limit value Va and held, the spool 70 can be localized at the limit position Rlia on the advance angle region Ra side in the lock introduction region Rli. According to this, not only when the localization position of the spool 70 in the holding period Th is the limit position Rlia in the regular lock introduction region Rli, even if the localization position is deviated to the advance angle region Ra side, The introduction flow rate to each advance chamber 22 can be ensured reliably. Therefore, it is possible to improve the reliability with respect to the effect of ensuring quietness.

(Third embodiment)
The third embodiment of the present invention is a modification of the second embodiment. In S104 of the variable setting flow according to the third embodiment, as shown in FIG. 15, after the control command value V is set to the release side limit value Va and the holding period Th is waited for, a step change is made at once to the aperture side limit value Vs. The command value V is held for a predetermined period Tha that is further added. Here, the additional holding period Tha for holding the control command value V step-changed to the throttle side limit value Vs side at the value Vs is set to a time obtained by subtracting the previous holding period Th from the filling time Tf. Is done.

  The control command value V can be varied so that the moving position of the spool 70 changes in time from the advance angle region Ra side to the lock throttle region Rls side in the lock introduction region Rli also by the step change after the holding described above. Can be set.

  In particular, when the control command value V set to the release side limit value Va is step-changed toward the throttle side limit value Vs, the spool 70 can be moved greatly. According to this, even if the movement position of the spool 70 according to the release side limit value Va deviates from the lock introduction area Rli to the advance angle area Ra side, the spool 70 is moved to the lock introduction area Rli by such a large movement. It can be definitely returned. Therefore, it is possible to increase the reliability with respect to the effect of ensuring the startability.

(Other embodiments)
Although a plurality of embodiments of the present invention have been described above, the present invention is not construed as being limited to these embodiments, and various embodiments and combinations can be made without departing from the scope of the present invention. Can be applied.

  For example, in the first modification, as long as the moving position of the spool 70 changes in time from the advance angle region Ra side toward the lock aperture region Rls side, the release side limit value Va of the variable setting source in S104 is the value Va. It may be replaced with a different control command value V. Specifically, as the control command value V that replaces the release side limit value Va, the lock throttle region Rls of the movement position of the spool 70 in the lock introduction region Rli than the limit position Rlia on the advance angle region Ra side. Current corresponding to the position on the side.

  In the second modification, as long as the moving position of the spool 70 changes with time from the advance angle region Ra side toward the lock throttle region Rls side, the aperture value limit value Vs of the variable setting destination in S104 is different from the value Vs. The control command value V may be replaced. Specifically, as the control command value V that replaces the throttle-side limit value Vs, the advance position area Ra of the limit position Rli on the lock throttle area Rls side in the movement position of the spool 70 in the lock introduction area Rli. Current corresponding to the position on the side.

  In the third modification, the flow rate of the engine oil introduced into each advance chamber 22 is controlled to the maximum flow rate other than the limit position Rlia on the advance angle region Ra side in the movement position of the spool 70 in the lock introduction region Rli. Also good. Further, in the case of the third modification, the control command value V, which is replaced with the release side limit value Va in the first modification, is used as the moving position of the spool 70 at which the flow rate of the engine oil introduced into each advance chamber 22 is maximized. You may make it correspond.

  In the fourth modification, as shown in FIG. 16, S202 and S203 related to the correction of the release side limit value Va in the correction flow may be omitted. Moreover, in the modification 5, as shown in FIG. 17, S204-S207 regarding correction | amendment of the aperture limit value Vs may be abbreviate | omitted among correction flows. Furthermore, in the sixth modification, the control circuit 90 may execute a computer program that does not perform the correction flow.

  In the modified example 7, as shown in FIG. 18, the additional holding period Tha after the step change after the holding period Th according to the third embodiment may be secured in a plurality of times. However, in the case of the modified example 8, the control command value V at the step change destination is set to one or a plurality of intermediate values Vm between the limit values Va and Vs. It is set so as to approach the aperture side limit value Vs as it advances. In the case of the modified example 8, the step is changed during each additional holding period Tha.

  In the modification 8, as shown in FIG. 19, the additional holding period Tha after the step change in the third embodiment may be replaced with a gradual change period Tc according to the second embodiment. However, in the case of the modified example 7, after the control command value V is step-changed to the intermediate value Vm between the limit values Va and Vs, a gradual change period Tc from the intermediate value Vm toward the aperture-side limit value Vs is secured. .

  In the modification 9, as shown in FIG. 20, the holding period Th before the step change in the modification 8 may be replaced with a gradual change period Tc according to the second embodiment. However, in the case of Modification 9, after securing a gradual change period Tc in which the control command value V gradually changes to the intermediate value Vm1 between the limit values Va and Vs, another intermediate value Vm2 between the limit values Va and Vs is secured. After the step change, the gradual change period Tc from the other intermediate value Vm2 is also secured. At this time, the intermediate value Vm2 of the step change destination is set closer to the diaphragm side limit value Vs than the intermediate value Vm1 of the step change source.

  In the modified example 10, instead of the advance angle region Ra, the retard angle region Rr or the holding region Rh may be adopted as the “lock release region”. In Modification 11, the relationship between “advance angle” and “retard angle” may be interchanged.

  In the modified example 12, the control valve 60 may be incorporated in one of the vane rotor 14 and the cam shaft 2 or may be disposed outside the vane rotor 14 and the cam shaft 2. Further, in Modification 13, for example, an electric piezo actuator or a hydraulic actuator may be employed as the drive source 82 of the control valve 60.

  In the modified example 14, as long as the engine oil is supplied along with the rotation of the internal combustion engine, for example, an electric pump or the like may be employed as the “supply source”. In Modification 15, the most retarded angle phase or the most advanced angle phase may be adopted as the starting phase Ps that locks the rotational phase.

  In the modification 16, the restriction hole 151 may not be provided in the lock unit 16. In the modified example 17, the assist spring 144 may not be provided in the phase adjustment unit 11. Furthermore, in the modified example 18, the present invention is applied to a system that variably controls the valve timing of the exhaust valve as a “valve”, or a system that variably controls the valve timing of both the intake valve and the exhaust valve as “valve” May be applied.

1 valve timing control system, 2 camshaft, 4 pump, 10 rotation mechanism system, 11 phase adjustment unit, 12 housing rotor, 14 vane rotor, 16 lock unit, 22 advance chamber, 24 retard chamber, 50 control system, 60 control Valve, 70 spool, 82 drive source, 90 control circuit, 160 lock member, 164 lock operation chamber, 168 lock hole, Dg forward direction, Dr return direction, Ps start phase, Ra advance angle region, Rli lock introduction region, Rlia, Rlis limit position, Rls lock throttle region, Tc gradual change period, Th holding period, Tha additional holding period, V control command value, Va release side limit value, Vac value approaching throttle side limit value, Vs throttle side limit value, Vsc Values approaching the release limit value, Δa, Δs Correction amount

Claims (8)

A valve timing control system (1) for variably controlling a valve timing of a valve that opens and closes a camshaft (2) by torque transmission from a crankshaft in an internal combustion engine,
Between the rotor (12, 14) that rotates in conjunction with the crankshaft and the camshaft, there is provided an adjusting operation chamber (22) into and out of the engine oil supplied with the rotation of the internal combustion engine. A phase adjustment unit (11) for adjusting the rotational phase of the camshaft relative to the crankshaft in response to the engine oil entering and exiting the chamber;
A lock operation chamber (164) provided in the phase adjustment unit and into and out of the engine oil is included, and the rotation phase is locked to a predetermined start phase (Ps) by discharging the engine oil from the lock operation chamber. On the other hand, a lock unit (16) for releasing the lock by introducing the engine oil into the lock working chamber;
A control valve (60) having a spool (70) reciprocally moving in the axial direction, and controlling the engine oil in and out of the adjustment working chamber and the lock working chamber according to the movement of the spool;
A control circuit (90) for setting a control command value (V) for controlling the movement position of the spool,
As the area where the spool moves,
A lock introduction region (Rli) for discharging the engine oil from the lock operation chamber and introducing the engine oil into the adjustment operation chamber;
A lock that is set on one side in the axial direction with respect to the lock introduction region, discharges the engine oil from the lock operation chamber, and restricts the introduction flow rate of the engine oil to the adjustment operation chamber more than the lock introduction region. An aperture region (Rls);
The lock oil introduction region is set on the opposite side of the lock restricting region with the lock introduction region sandwiched in the axial direction, and the engine oil is introduced into the lock operation chamber where the discharge of the engine oil is stopped, and the adjustment operation chamber is introduced into the adjustment operation chamber. A lock release region (Ra) for controlling the flow rate of introduction of the engine oil to a flow rate necessary for adjusting the rotational phase is set;
The control circuit includes:
Command value setting for variably setting the control command value so that the moving position of the spool in the lock introduction region changes from the lock release region to the lock throttle region when the internal combustion engine is started Means (S104). A valve timing control system comprising: A control command value for moving the spool to a limit position (Rlia) on the lock release area side in the lock introduction area is defined as a release side limit value (Va),
When a control command value for moving the spool to a limit position (Rlis) on the lock throttle region side in the lock introduction region is defined as a throttle side limit value (Vs),
The command value setting means changes the control command value from the release-side limit value to the throttle-side limit value after setting the control command value to the release-side limit value. The valve timing control system described.   The said command value setting means changes the said control command value gradually toward the said diaphragm | throttle side limit value side, after setting the said control command value to the said cancellation | release side limit value. Valve timing control system.   The said command value setting means sets the said control command value to the said cancellation | release side limit value, Then, changes the said control command value toward the said diaphragm | throttle side limit value side, It is characterized by the above-mentioned. The valve timing control system described.   The command value setting means changes the control command value toward the aperture side limit value side after securing a holding period (Th) for setting and holding the control command value at the release side limit value. The valve timing control system according to any one of claims 2 to 4, wherein:   6. The flow rate of introduction of the engine oil into the adjustment working chamber is maximized at a limit position on the unlocking region side in the lock introduction region. 6. Valve timing control system. The control circuit includes:
Continuation determining means (S201) for determining whether the variable setting of the control command value by the command value setting means is continuing or ended;
A phase shift determination unit (S202) that determines whether or not a shift of the rotational phase from the starting phase has occurred when it is determined by the continuation determination unit that the variable setting is being continued;
When it is determined that the shift has occurred by the phase shift determination unit, a release side correction unit (S203) that corrects the release side limit value to a value (Vac) that approaches the aperture side limit value from a current value;
The valve timing control system according to any one of claims 1 to 6, wherein: The control circuit includes:
Continuation determining means (S201) for determining whether the variable setting of the control command value by the command value setting means is continuing or ended;
Phase vibration determination means (S206) for determining whether or not vibration of the rotational phase has occurred when it is determined by the continuation determination means that the variable setting has been completed;
A diaphragm side correcting means (S207) for correcting the diaphragm side limit value to a value (Vsc) approaching the release side limit value from the current value when the phase vibration determining means determines that the vibration has occurred;
8. The valve timing control system according to claim 1, wherein the valve timing control system includes:

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