JP6409641B2 - Valve timing control system - Google Patents

Description

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

  2. Description of the Related Art Conventionally, a valve timing control system that controls a lock unit that switches between locking and releasing of the rotation phase, as well as a phase adjustment unit that adjusts the rotation phase between the crankshaft and the camshaft, is widely known.

  For example, in the system disclosed in Patent Document 1, the flow of hydraulic fluid to and from each of the phase adjustment unit and the lock unit is controlled according to the control command value set by the control unit. As a result, according to the phase adjustment unit, the rotational phase is adjusted by controlling the flow of hydraulic fluid into and out of the adjustment working chamber between the pair of rotors that rotate in conjunction with the crankshaft and the camshaft. Further, according to the lock unit, the hydraulic fluid is controlled in and out of the lock working chamber in the phase adjusting unit, so that the intermediate phase shifted from the extreme end phase (hereinafter also simply referred to as “intermediate phase”). The rotation phase can be locked and released.

  Now, in the system disclosed in Patent Document 1, the adjustment of the rotational phase exceeding the extreme end phase is regulated by the contact of the stoppers provided in each rotor of the stopper unit. Thus, the extreme end phase when the stoppers come into contact with each other is determined with relatively high accuracy. Therefore, after learning of the endmost phase is completed, the phase difference of the intermediate phase with respect to the endmost phase is learned, and the rotational phase is controlled to the intermediate phase calculated from the learned value of the phase difference and the endmost phase. It is possible to do.

JP 2010-275911 A

  However, in the system disclosed in Patent Document 1, for example, a torque transmission member such as a timing chain or a timing belt expands / contracts due to a change in environmental temperature, so that the phase difference of the intermediate phase with respect to the extreme end phase varies. easy. Therefore, when the environmental temperature changes, an error occurs in the learning value of the phase difference and the calculated value of the intermediate phase depending on it. As a result, when the rotational phase is controlled to the calculated intermediate phase, there is a concern that it is difficult to properly complete the lock.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a valve timing control system that can properly complete locking in an intermediate phase even when the environmental temperature changes. is there.

  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 first invention disclosed in order to solve the above-mentioned problem is
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 through a torque transmission member (6) in an internal combustion engine,
An adjustment working chamber (22, 24) is formed between a pair of rotors (12, 14) that rotate in conjunction with the crankshaft and the camshaft, respectively, and the crankshaft and camshaft according to the flow of hydraulic fluid into and out of the adjustment working chamber. A phase adjustment unit (11) for adjusting the rotational phase between
A stopper unit (15) having stoppers (150, 151, 152, 153) provided on each rotor, and regulating the adjustment of the rotational phase exceeding the extreme end phase (Pr) by contact between the stoppers;
A lock working chamber (164) is formed in the phase adjusting unit, and the lock unit (16) switches between locking and releasing of the rotational phase in the intermediate phase (Pm) deviated from the endmost phase by the entry and exit of the working fluid into and from the lock working chamber. )When,
A control unit (90) for setting a control command value (V) for controlling the flow of hydraulic fluid into and out of the adjustment working chamber and the lock working chamber,
When defining the reference phase difference (MP) as the phase difference of the intermediate phase with respect to the extreme end phase,
The control unit
Phase difference learning means (S201 to S217, S2218 to S2220, S3221) for learning the reference phase difference in correspondence with the environmental temperature (TP);
Endmost phase learning means (S401 to S405) for learning the endmost phase;
Intermediate phase calculating means (S102 to S105) for calculating an intermediate phase from the learning value of the reference phase difference by the phase difference learning means and the learning value of the extreme end phase by the extreme edge phase learning means;
Intermediate phase control means (S101, S106 to S106) for determining a control command value so as to control the rotational phase to the intermediate phase calculated by the intermediate phase calculation means when the lock condition (Cl) for locking the rotational phase is satisfied. S108) is constructed by at least one processor (900).

  According to such a first invention, when the lock condition is satisfied, the intermediate phase is calculated from the learning value of the reference phase difference, which is the phase difference of the intermediate phase with respect to the outermost phase, and the learned value of the outermost phase, The rotational phase is controlled to the calculated value of the intermediate phase. Here, since the reference phase difference is learned according to the environmental temperature, an error does not easily occur in the learning value of the reference phase difference and the calculated value of the intermediate phase depending on the learning value even if the environmental temperature changes. According to this, since the rotational phase can be controlled to the intermediate phase that can be calculated with high accuracy, it becomes possible to properly complete the locking in the intermediate phase.

The disclosed second invention is:
A release phase difference (MPc) is defined as a reference phase difference at the time of release execution from when the release condition (Cc) for releasing the lock of the rotational phase is established until the release is completed,
When the phase difference at the time of lock (MPl) is defined as a reference phase difference at the time of lock execution from when the lock condition is satisfied until the lock of the rotation phase is completed,
The phase difference learning means determines that at least one of the phase difference at the time of release and the phase difference at the time of lock when determining that the mutual shift amount of the phase difference at the time of release and the phase difference at the time of lock is equal to or less than an allowable amount (δMPp). The learning value of the reference phase difference is acquired based on the above.

  According to the second invention as described above, with respect to the phase difference at the time of release when the release condition is established until the release is completed, and the phase difference at the time of lock execution when the lock condition is established until the lock is completed In a situation where one of them becomes unstable, the amount of mutual deviation tends to increase. Therefore, when it is determined that the mutual deviation amount is less than the allowable amount, the reference position is determined based on at least one of the phase difference at release and the phase difference at lock as a stable reference phase difference. The learning value of the phase difference can be obtained accurately. According to this, since it is possible to suppress the occurrence of an error in the calculated value of the intermediate phase that depends on the learning value of the reference phase difference, it becomes possible to properly complete the locking at the intermediate phase.

Further, the disclosed third invention is:
Define the temperature at release (TPc) as the environmental temperature at the time of release,
If the lock temperature (TPl) is defined as the environmental temperature during lock execution,
The phase difference learning means is characterized in that learning of the reference phase difference is prohibited when it is determined that the temperature difference between the release temperature and the lock temperature exceeds the allowable difference (δTPp).

  According to the third invention as described above, the temperature at the time of release when the phase difference at the time of release is realized and the temperature at the time of lock when the phase difference at the time of lock is realized are between the execution times. As the environmental temperature changes, the temperature difference between them increases. Therefore, when it is determined that the temperature difference is equal to or greater than the allowable difference, even if stable phase difference at release and phase difference at lock are realized, it is based on at least one of the phase differences. Learning of the reference phase difference is prohibited. According to this, it is possible to avoid a situation in which an erroneous reference phase difference is learned due to a change in environmental temperature, so that an error occurs in the calculated value of the intermediate phase that depends on the learned value of the reference phase difference. Can be suppressed. Therefore, this is effective in properly completing the lock in the intermediate phase.

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 time chart for demonstrating the operation example of the valve timing system 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. 4 is a graph for explaining a reference phase difference stored in a memory of FIG. 1. 2 is a graph for explaining a most retarded angle phase stored in a memory of FIG. 1. It is a flowchart which shows the lock control flow implement | achieved by the control unit of FIG. It is a flowchart which shows a part of phase difference learning flow implement | achieved by the control unit of FIG. It is a flowchart which shows the remainder of the phase difference learning flow implement | achieved by the control unit of FIG. It is a flowchart which shows the extreme end phase control flow implement | achieved by the control unit of FIG. It is a flowchart which shows the endmost phase learning flow implement | achieved by the control unit of FIG. It is a flowchart which shows the phase difference learning flow implement | achieved by the control unit of 2nd embodiment. It is a flowchart which shows the phase difference learning flow implement | achieved by the control unit of 3rd embodiment. It is a flowchart which shows the modification of FIG. It is a flowchart which shows the modification of FIG. It is a flowchart 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” in which the camshaft 2 is opened and closed by torque transmission from the crankshaft in the internal combustion engine. The system 1 implements variable control of valve timing by using, as “hydraulic fluid”, hydraulic fluid supplied from a pump 4 as a supply source and lubricating the internal combustion engine. Specifically, the system 1 includes a rotation mechanism system 10 and a control system 50 as shown in FIGS.

(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, a stopper unit 15, a lock unit 16, and an assist unit 17.

(Phase adjustment unit)
The phase adjustment unit 11 is configured by combining the outer rotor 12 and the inner rotor 14 as “a pair of rotors”.

  The outer rotor 12 is formed in a hollow shape as a whole. In the outer rotor 12, plates 12b and 12c are fastened to both ends of the shoe housing 12a in the axial direction. 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 the timing chain 6 as a “torque transmission member”. With this connection, during rotation of the internal combustion engine, transmission of crank torque from the crankshaft to the sprocket 124 causes the outer rotor 12 to rotate in a fixed direction (clockwise in FIG. 2) in conjunction with the crankshaft.

  The inner rotor 14 is accommodated coaxially in the outer rotor 12. The inner rotor 14 is in sliding contact with both ends in the axial direction on the plates 12b and 12c. The inner 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 inner rotor 14 can rotate relative to the outer rotor 12 while rotating in the same direction as the outer rotor 12 (clockwise in FIG. 2) in conjunction with the camshaft 2.

  A substantially fan-shaped vane 142 protrudes outward in the radial direction from a position spaced apart by a predetermined interval in the rotation direction on the rotation 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. Is formed with a retarding angle chamber 24 as an “adjusting working chamber”. That is, a plurality of advance chambers 22 and retard chambers 24 are provided alternately between the inner rotor 14 and the outer rotor 12 in the rotational direction.

  The phase adjustment unit 11 having such a configuration determines the valve timing by adjusting the rotational phase between the crankshaft and the camshaft 2 in accordance with the entry and exit of the hydraulic oil to and from each advance chamber 22 and each retard chamber 24. Specifically, the inner rotor 14 rotates relative to the outer rotor 12 in the advance direction by introducing the hydraulic oil into each advance chamber 22 and discharging the hydraulic 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 inner rotor 14 rotates relative to the outer rotor 12 in the retarding direction by introducing the working oil into each retarding chamber 24 and discharging the working 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 and exit of the hydraulic oil to and from each advance chamber 22 and each retard chamber 24, the relative rotation of the inner rotor 14 with respect to the outer rotor 12 does not occur due to the entry and 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.

(Stopper unit)
As shown in FIG. 2, the stopper unit 15 is configured by combining inner stoppers 150 and 151 provided on the inner rotor 14 and outer stoppers 152 and 153 provided on the outer rotor 12.

  The advance angle inner stopper 150 is formed by a side surface facing the advance angle direction in the vane 142a having the maximum width in the rotation direction. The retard inner stopper 151 is formed by a side surface that faces the retard direction in the same vane 142 a as the advance inner stopper 150.

  The advance outer stopper 152 is formed by a side surface facing the advance inner stopper 150 in the shoe 122a positioned in the advance direction of the vane 142a. The retard outer stopper 153 is formed by a side surface facing the retard inner stopper 151 in the shoe 122b located in the retard direction of the vane 142a.

  In the most advanced angle phase of the rotational phase, the advanced angle inner stopper 150 contacts the advanced angle outer stopper 152 in the advanced angle direction. Thereby, the advance angle adjustment of the rotational phase exceeding the most advanced angle phase is regulated. On the other hand, in the most retarded phase Pr as the “most end phase” shown in FIG. 3B among the rotational phases, the retard inner stopper 151 abuts against the retard outer stopper 153 in the retard direction. Thereby, the retardation adjustment of the rotation phase exceeding the most retardation angle Pr is regulated.

(Lock unit)
As shown in FIGS. 1, 2, 5 to 9, the lock unit 16 includes a lock member 160, an urging member 162, a lock operation chamber 164, a restriction hole 166, and a lock hole 168.

  The cylindrical lock member 160 is arranged eccentrically with respect to the rotation shaft 140. The lock member 160 is movably supported by a vane 142b that does not form the inner stoppers 150 and 151 of the inner rotor 14. The coil spring-like urging member 162 is eccentric from the rotating shaft 140 and is arranged coaxially with the lock member 160. The urging member 162 is interposed between the lock member 160 and the vane 142b 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.

  In the phase adjustment unit 11, an annular space is always formed between the lock member 160 and the vane 142b as the lock operation chamber 164 through which hydraulic oil enters and exits. A driving force acts on the lock member 160 toward the rear plate 12b opposite to the front plate 12c by the pressure of the hydraulic oil introduced into the lock working chamber 164.

  The bottomed long hole-like restriction hole 166 extends along the rotation direction at a portion of the outer rotor 12 that is eccentric from the rotation shaft 140 in the front plate 12c. The bottomed cylindrical hole-shaped lock hole 168 is formed in the front plate 12c at a location that is eccentric from the rotating shaft 140, and is open to the bottom surface of the end in the advance direction of the restriction hole 166.

  The lock unit 16 having such a configuration switches between locking and releasing of the rotation phase when hydraulic oil enters and exits the lock working chamber 164. Specifically, the lock member 160 escapes from both the lock hole 168 and the restriction hole 166 by introducing hydraulic oil into the lock working 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 hydraulic 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 Pr and the most advanced angle phase, the lock member 160 is biased. In response to the restoring force of 162, only the restriction hole 166 enters (see FIG. 1). As a result, the rotation phase is regulated within the regulation phase range. Further, under the restricted state, when the rotational phase reaches a predetermined intermediate phase Pm (see FIG. 3B) that is deviated from the most retarded phase Pr in the restricted phase range, the locking member 160 restores the restoring force of the biasing member 162. Is received and inserted into the lock hole 168 (see FIGS. 5 and 6). As a result, the rotational phase is locked in the intermediate phase Pm. Here, the regulation phase range is preset to a rotation phase range that allows the start of the internal combustion engine, and the intermediate phase Pm is preset to a rotation phase that is particularly suitable for startability within the regulation phase range.

(Assist unit)
As shown in FIG. 1, the assist unit 17 is configured by combining an assist spring 170 and locking pins 171 and 172.

  In the spiral assist spring 170, the inner peripheral end 170 a is held by a bush 140 a that protrudes out of the outer rotor 12 of the rotating shaft 140 of the inner rotor 14. The outer peripheral side end 170b of the assist spring 170 is locked by the first locking pin 171 until the rotation phase reaches from the most retarded phase to the intermediate phase Pm. Here, the first locking pin 171 is provided so as to be integrally rotatable with the front plate 12 c of the outer rotor 12. Thereby, in the rotational phase from the most retarded phase to the intermediate phase Pm, the inner rotor 14 is urged in the advance direction by the restoring force generated by the elastically deformed assist spring 170. On the other hand, the outer peripheral side end 170b of the assist spring 170 is locked by the second locking pin 172 until the rotational phase reaches the most advanced angle phase from the intermediate phase Pm. Here, the second locking pin 172 is provided on the arm 140 b that rotates integrally with the bush 140 a outside the outer rotor 12 in the inner rotor 14. As a result, in the rotational phase from the intermediate phase Pm to the most advanced angle phase, the urging of the inner rotor 14 by the assist spring 170 is limited.

(Control system)
The control system 50 shown in FIGS. 1 and 2 controls the operation oil to enter and exit from the chambers 22, 24 and 164 in order to drive the rotating mechanism system 10. 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, a sub supply passage 57, a drain recovery passage 58, a control valve. 60 and a control unit 90 are provided.

(aisle)
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 conveyance passage 3 shown in FIG. 1 in the internal combustion engine. Here, the pump 4 is a mechanical pump that is driven by receiving crank torque from the crankshaft as the internal combustion engine rotates. During the rotation, the hydraulic oil sucked from the drain pan 5 is continuously discharged. The conveyance passage 3 communicates with the discharge port of the pump 4 to convey the hydraulic fluid that has been diverted from the flow toward the lubrication point of the internal combustion engine. At the same time, the transfer passage 3 passes through the camshaft 2 to transfer the hydraulic oil diverted from the pump to the main supply passage 56. As described above, during the rotation until the internal combustion engine is started and stopped, the hydraulic oil is supplied from the pump 4 to the main supply passage 56 through the transfer passage 3, while the internal combustion engine is stopped and started next time. 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 hydraulic oil supplied from the pump 4 through the main supply passage 56. As shown in FIG. 1, lead type check valves 57 a and 56 a are provided in the middle part of the sub supply passage 57 and in the middle part of the main supply passage 56 on the side of the pump 4 with respect to the branching portion of the passage 57. Each is provided (see also FIGS. 5 to 9). Here, the sub check valve 57 a prevents the hydraulic oil from flowing back to the main supply passage 56 side in the sub supply passage 57. The main check valve 56 a prevents the hydraulic oil from flowing back to the pump 4 side in the main supply passage 56.

  The drain collection passage 58 is provided outside the rotation mechanism system 10 and the cam shaft 2. The drain collection passage 58 is open to the atmosphere and can discharge hydraulic oil toward the drain pan 5 as a drain collection unit.

(Control valve)
As shown in FIGS. 1, 2, 5 to 9, the control valve 60 is a spool valve configured by combining a sleeve 66, a spool 70, an elastic member 80, and a drive source 82.

  The cylindrical sleeve 66 is coaxially built in the inner rotor 14 so as to straddle the rotation shaft 140 and the camshaft 2, and is arranged so as to be rotatable integrally with the elements 14 and 2. A screw portion 66 a (see FIG. 1) on the bottom end side of the sleeve 66 is screwed coaxially with the cam shaft 2. A flange portion 66 b (see FIG. 1) on the opening end side of the sleeve 66 sandwiches the rotating shaft 140 between the cam shaft 2 and connects the inner rotor 14 to the cam shaft 2. The sleeve 66 includes one 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 from to. 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 each drain port 666 communicates with the drain collection passage 58.

  The cylindrical spool 70 is coaxially accommodated in the sleeve 66 so that it can rotate integrally with the inner rotor 14 and the cam shaft 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 and the backward direction Dr in the axial direction. In the spool 70, a communication passage 705 is 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 in order to reduce the flow amount of hydraulic oil between the advance port 661 and the main supply port 664 at a specific movement position (see FIG. 6).

  In such a configuration, the control valve 60 has a plurality of regions Rli, Rls, Ra as shown in FIG. 4 as regions where the spool 70 moves in order to individually control the flow of hydraulic oil to and from the chambers 22, 24, 164. , Rh, 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 hydraulic oil supplied from the pump 4 to the passages 3 and 56 is introduced into each advance chamber 22 through the ports 664 and 661 and the passages 52 and 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, hydraulic oil is sequentially discharged from each retard 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, hydraulic 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, and is located in the backward direction Dr with respect to the lock introduction region Rli. 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, due to the function of the throttle portion 704, the flow rate of the hydraulic oil introduced into each advance chamber 22 is smaller than the lock introduction region Rli according to the small flow area between the ports 661 and 664 shown in FIG. Is also squeezed.

  The advance angle region Ra of FIG. 4 is positioned in the forward direction Dg with respect to the lock introduction region Rli by setting the lock introduction region Rli in the axial direction and on the opposite side of the lock throttle region Rls. 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 hydraulic oil supplied from the pump 4 to the passages 3 and 56 is introduced into each advance chamber 22 through the ports 664 and 661 and the passages 52 and 51. At this time, the flow rate of the hydraulic oil introduced into each advance chamber 22 is controlled to a flow rate required for the advance adjustment of the rotation 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, hydraulic oil is sequentially discharged from each retard 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 hydraulic oil supplied from the pump 4 to the passages 3, 56 and 57 is introduced into the lock working chamber 164 through the ports 665 and 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 the entry / exit of the hydraulic oil to / from 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, hydraulic oil supplied from the pump 4 to the passages 3, 56 and 57 is introduced into the lock working chamber 164 through the ports 665 and 663 and the passage 55.

  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, hydraulic oil is sequentially discharged from each advance chamber 22 to the passage 58 and the 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 hydraulic oil supplied from the pump 4 to the passages 3 and 56 is introduced into each retarded angle chamber 24 through the ports 664 and 662 and the passages 54 and 53. Further, in the retardation region Rr, the lock port 663 is connected to the sub supply port 665. With this connection form, the hydraulic oil supplied from the pump 4 to the passages 3, 56, 57 is introduced into the lock working chamber 164 through the ports 665, 663 and the passage 55.

  As shown in FIGS. 1 and 5 to 9, 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 such as a chain cover in the internal combustion engine. The drive source 82 is an electromagnetic solenoid in the present embodiment, and controls the movement position of the spool 70 by receiving power to the built-in coil. 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. The drive shaft 82 a can enter into one drain port 666 formed by the opening of the sleeve 66. The drive shaft 82a always abuts against the other end of the spool 70.

  In such a driving source 82, the driving force in the forward direction Dg acts on the spool 70 in the contact state from the driving shaft 82a according to the energization of the built-in coil. As a result, the driving force from the driving source 82 balances with the restoring force of the elastic member 80, whereby the movement of the spool 70 to each region Rli, Rls, Ra, Rh, Rr is realized.

(Controller unit)
A control unit 90 shown in FIG. 1 is an electronic circuit mainly composed of a microcomputer, and includes a processor 900 and a memory 901. The control unit 90 is electrically connected to various electrical components such as sensors 7, 8, 9 provided in the internal combustion engine and a drive source 82. Here, the temperature sensor 7 is, for example, a cooling water temperature sensor or an oil temperature sensor, and outputs a signal representing the water temperature or the oil temperature to the control unit 90 as the environmental temperature TP. The crank sensor 8 is, for example, an electromagnetic pickup type rotation angle sensor or the like, and outputs a signal representing the crank shaft rotation angle θcra to the control unit 90. The cam sensor 9 is, for example, an electromagnetic pickup type rotation angle sensor, and outputs a signal representing the rotation angle θcam of the cam shaft 2 to the control unit 90.

  The control unit 90 controls the operation of the internal combustion engine including energization to the drive source 82 by executing various control programs stored in the memory 901 by the processor 900. At this time, the control unit 90 acquires the actual phase based on the detected rotation angles θcra and θcam by the sensors 8 and 9 and the target phase based on the operating condition of the internal combustion engine with respect to the rotational phase. Further, the control unit 90 determines the duty ratio of the energization current for the drive source 82 as the control command value V of the feedback control based on the obtained deviation between the actual phase and the target phase (see FIG. 3B). Alternatively, the control unit 90 determines the duty ratio of the energization current for the drive source 82 as the control command value V of the open loop control based on the acquired target phase. Then, the control unit 90 provides the drive source 82 with an energization current according to the control command value V of the feedback control or open loop control determined in this way. As a result, the spool 70 moves to any one of the regions Rli, Rls, Ra, Rh, and Rr, whereby the hydraulic oil enters and exits the chambers 22, 24, and 164.

  Here, specifically, the control unit 90 moves the spool 70 to the lock introduction region Rli during the start period in which the internal combustion engine is cranked in response to the start command. As a result, the rotational phase is controlled and locked to the intermediate phase Pm. The start command is, for example, a power switch on command or an idle stop system restart command.

  Further, in the normal operation period after the internal combustion engine is started in this way, when the release condition Cc (see FIG. 3A) for releasing the lock of the rotation phase is satisfied, the control unit 90 performs the advance angle region Ra, the holding region. The spool 70 is moved to one of Rh and the retarded angle region Rr. Accordingly, when the lock is released, any one of the advance angle adjustment, the hold adjustment, and the retard angle adjustment is performed on the rotation phase. The release condition Cc is preset at, for example, the timing when the vehicle starts traveling at a low speed.

  On the other hand, even during the normal operation period of the internal combustion engine, the control unit 90 moves the spool 70 to the lock throttle region Rls when the lock condition Cl (see FIG. 3A) for locking the rotation phase is satisfied. As a result, the rotational phase is locked to the intermediate phase Pm. The lock condition Cl is preset at, for example, the timing at which the vehicle decelerates under low speed traveling or the timing at which idling of the internal combustion engine starts.

  Here, particularly in the present embodiment, in the state of FIG. 3B in which the rotational phase at the time when the lock condition Cl is satisfied is advanced from the intermediate phase Pm, the spool 70 is moved prior to the movement to the lock aperture region Rls. Is moved to the retardation region Rr. This is because, by moving to the retard angle region Rr, the rotational phase is once reached the lock start phase Ps around the retard side of the intermediate phase Pm, and then moved to the lock aperture region Rls. This is to facilitate the locking to the phase Pm.

  On the other hand, in a state where the rotational phase when the lock condition Cl is satisfied is retarded from the intermediate phase Pm (not shown), the spool 70 is moved to the advance angle region Ra prior to the movement to the lock aperture region Rls. Let This is because, by moving to the advance angle region Ra, the rotational phase is temporarily reached to the lock start phase Ps around the retard side of the intermediate phase Pm, and then moved to the lock aperture region Rls. This is to facilitate the locking to the phase Pm.

  As described above, when the lock condition Cl is satisfied, the control unit 90 sets the lock start phase Ps as a rotation phase for starting the lock by the lock unit 16 as close as possible to the periphery of the retard side of the intermediate phase Pm. Here, the lock start phase Ps is variably set according to a calculated value of the intermediate phase Pm based on a learned value of the reference phase difference MP, which will be described in detail later. Note that, for the same intermediate phase Pm, the lock start phase Ps has the same value in the state where the rotational phase when the lock condition Cl is satisfied is advanced and retarded relative to the intermediate phase Pm. It may be set or may be set to a different value.

  Since the lock condition Cl is satisfied during the stop operation period in which the internal combustion engine stops after the inertial rotation in response to the stop command, the control unit 90 continues the spool 70 to the lock restricting region Rls from that time. Let it be localized. As a result, the rotational phase remains locked to the intermediate phase Pm. The stop command is, for example, a power switch off command or an idle stop system pause command.

(Learn reference phase difference and most retarded phase)
The reference phase difference MP shown in FIG. 10 is learned as a phase difference of the intermediate phase Pm with respect to the most retarded phase Pr by the control unit 90 in correspondence with the environmental temperature TP, so that a stored value stored in the memory 901 is obtained. Readable. Here, particularly in this embodiment, a plurality of temperature ranges Stp are preset by dividing the entire operating temperature range of the system 1 with respect to the environmental temperature TP, and a different reference phase difference MP is learned for each temperature range Stp. Thus, the learned value is read as a stored value in the memory 901. However, until the first learning is executed for each temperature range Stp after the system 1 is shipped from the factory, the initial value MP0 of the reference phase difference MP preset by, for example, design specifications or experiments is stored in the memory 901. Read as stored value. The spans of the temperature ranges Stp may be the same as shown in FIG. 10 or may be different from each other although not shown.

  Similarly, the most retarded phase Pr shown in FIG. 11 can be read out as a stored value stored in the memory 901 by learning by the control unit 90 in correspondence with the environmental temperature TP. Here, particularly in the present embodiment, a different reference phase difference MP is learned for each temperature range Stp preset with respect to the environmental temperature TP, and the learned value is read as a stored value of the memory 901. However, until the first learning is executed for each temperature range Stp after the factory shipment of the system 1, the initial value Pr0 of the most retarded phase Pr preset by, for example, design specifications or experiments is stored in the memory 901. As a stored value. Each temperature range Stp associated with the most retarded phase Pr and each temperature range Stp associated with the reference phase difference MP may be the same as shown in FIGS. They may be different from each other.

  As described above, the memory 901 storing the learning values of the reference phase difference MP and the most retarded phase Pr is configured by using one or a plurality of storage media such as a semiconductor memory, a magnetic medium, or an optical medium, for example. Is done.

(Lock control flow)
The lock control flow shown in FIG. 12 is realized by the processor 900 executing the lock control program stored in the memory 901 by the processor 900. Therefore, the details of the lock control flow will be described below with reference to FIG. The lock control flow and other flows described in detail later are started in response to the power switch ON command and are ended in response to the switch OFF command. In the lock control flow and other flows described in detail later, “S” means each step.

  In S101 of the lock control flow, it is determined whether or not a lock condition Cl for locking the rotation phase is satisfied. As a result, while the negative determination is made, S101 is repeatedly executed. When the positive determination is made, the process proceeds to S102.

  In S102, the current environmental temperature TP is acquired. At this time, the environmental temperature TP is detected by the temperature sensor 7. In subsequent S103, the stored value corresponding to the environmental temperature TP acquired in S102 is read as the learned value of the reference phase difference MP stored in the memory 901. In subsequent S104, the stored value corresponding to the environmental temperature TP acquired in S102 is read as the learned value of the most retarded phase Pr stored in the memory 901.

  In the subsequent S105, the current intermediate phase Pm is calculated from the learned value of the reference phase difference MP read in S103 and the learned value of the most retarded phase Pr read in S104. At this time, the intermediate phase Pm is calculated by adding the learning value of the reference phase difference MP to the learning value of the most retarded phase Pr.

  In S106, a control command value V to be supplied to the drive source 82 is set so that the lock start phase Ps is set around the intermediate phase Pm calculated in S105 and feedback control is performed using the lock start phase Ps as a target phase. To decide. As a result, when the current rotational phase is advanced from the intermediate phase Pm, the rotational phase is controlled so as to approach the lock start phase Ps by moving the spool 70 to the retardation region Rr. On the other hand, when the current rotational phase is retarded from the intermediate phase Pm, the rotational phase is controlled to approach the lock start phase Ps by moving the spool 70 to the advance angle region Ra.

  In S107 that moves after S106, it is determined whether or not the rotation phase has reached the lock start phase Ps. As a result, while the negative determination is made, S107 is repeatedly executed. When the positive determination is made, the process proceeds to S108.

  In S108, this time, the control command value V to be given to the drive source 82 is determined so as to perform open loop control using the intermediate phase Pm calculated in S105 as a target phase. As a result, when the spool 70 moves to the lock restriction region Rls, the control to the intermediate phase Pm is started, so that the rotational phase reaches the intermediate phase Pm and is locked. After the above, the process returns to S101.

(Phase difference learning flow)
The phase difference learning flow shown in FIGS. 13 and 14 is realized by the processor 900 executing the phase difference learning program stored in the memory 901 by the processor 900. Therefore, in the following, details of the phase difference learning flow will be described with reference to FIGS.

  As shown in FIG. 13, in S201 of the phase difference learning flow, it is determined whether or not a release condition Cc for unlocking the rotation phase is satisfied. As a result, while the negative determination is made, S201 is repeatedly executed. When the positive determination is made, the process proceeds to S202.

  In S202, the release-time phase Pmc is acquired as the intermediate phase Pm at the time of release execution from when the release condition Cc is satisfied until the lock release is completed. The release-time phase Pmc obtained at this time is an actual phase of the rotation phase based on the rotation angles θcra and θcam detected by the sensors 8 and 9. In subsequent S203, the release-time temperature TPc is acquired as the environmental temperature TP at the time of release execution in which the release-time phase Pmc is realized. At this time, the release temperature TPc is detected by the temperature sensor 7.

  In the subsequent S204, the stored value corresponding to the release temperature TPc acquired in S203 is read as the learned value of the most retarded phase Pr stored in the memory 901. In the subsequent S205, the release phase difference MPc is calculated as the reference phase difference MP that is the difference from the learned value of the most retarded phase Pr acquired in S204 with respect to the release phase Pmc acquired in S202.

  In S206, which proceeds after calculating the release phase difference MPc as described above, it is determined whether or not a lock condition Cl for locking the rotational phase is satisfied. As a result, while the negative determination is made, S206 is repeatedly executed. When the positive determination is made, the process proceeds to S207.

  In S207, it is determined whether or not the rotation phase has reached the lock start phase Ps. As a result, while the negative determination is made, S207 is repeatedly executed. When the positive determination is made, the process proceeds to S208.

  In S208, it is determined whether or not the set time tm has elapsed since the rotation phase reached the lock start phase Ps. At this time, the set time tm is preset to a time required for the rotation phase controlled to the intermediate phase Pm to be stabilized by the lock after reaching the lock start phase Ps, for example, about 1 second. In S208, while the negative determination is made, the same S208 is repeatedly executed. When the positive determination is made, the process proceeds to S209.

  As shown in FIG. 14, in S209, the lock phase Pml is acquired as an intermediate phase Pm at the time of lock execution from when the lock condition Cl is satisfied until the rotation phase lock is completed. The lock-time phase Pml acquired at this time is the actual phase of the rotation phase based on the detected rotation angles θcra and θcam by the sensors 8 and 9. In subsequent S210, the lock temperature TPl is acquired as the environmental temperature TP at the time of lock execution in which the lock phase Pml is realized. At this time, the lock temperature TPl is detected by the temperature sensor 7.

  In subsequent S211, the stored value corresponding to the locked temperature TPl acquired in S210 is read as the learned value of the most retarded phase Pr stored in the memory 901. In the subsequent S212, the locked phase difference MPl is calculated as the reference phase difference MP that is the difference from the learned value of the most retarded phase Pr acquired in S211 with respect to the locked phase Pml acquired in S209.

  In step S213, after the lock phase Pml is calculated in this way, the release-time phase difference MPc calculated in step S205 is compared with the lock-time phase difference MPl obtained in step S212. It is determined whether or not the amount is less than or equal to the allowable amount δMPp. At this time, when the release phase difference MPc and the lock phase difference MPl are both stable, the allowable amount δMPp is an allowable value, for example, 3 in terms of the crankshaft rotation angle. Preset to about degrees. In such S213, when a positive determination is made, the process proceeds to S214.

  In S214, the release temperature TPc acquired in S203 is compared with the lock temperature TPl acquired in S210, and it is determined whether or not the temperature difference exceeds the tolerance δTPp. At this time, the tolerance δTPp is preset to an allowable value for learning the reference phase difference MP, for example, about 5 ° C., as the amount of change in the environmental temperature TP that occurs between the time of release and the time of lock. The

  As described above, when a negative determination is made in S214 after an affirmative determination in S213, S215 and S216 are sequentially executed. Specifically, in S215, the reference phase difference MP is learned in correspondence with the environmental temperature TP. At this time, the current learning value of the reference phase difference MP is acquired based on at least one of the unlocking phase difference MPc calculated in S205 and the locking phase difference MPl calculated in S212. Here, particularly in the present embodiment, the reference phase difference MP at the time of current learning is calculated from the average value of the phase difference MPc at the time of release and the phase difference MPl at the time of lock, and becomes the current learning value. Further, as the environmental temperature TP, the unlocking temperature TPc acquired at S203 when the unlocking phase difference MPc is realized, and the locking time acquired at S210 when the locking phase difference MPl is realized. At least one of the temperatures TP1 is used. Here, in particular, in the present embodiment, the environmental temperature TP at the current learning is calculated from the average value of the release temperature TPc and the lock temperature TPl, and is associated with the current learning value of the reference phase difference MP.

  Next, in S216, in the memory 901, the stored value of the reference phase difference MP corresponding to the current range Stpt as the temperature range Stp to which the environmental temperature TP at the current learning belongs is stored in the memory 901 as the current learning of the reference phase difference MP acquired in S215. Update with values. After this, the process returns to S201.

  Now, in both cases where the negative determination in S213 is made and in the case where the positive determination in S214 is made after the positive determination in S213, the process proceeds to S217. In S217, learning of the reference phase difference MP is prohibited by skipping S215 and S216, and then the process returns to S201.

(Endmost phase control flow)
The extreme end phase control flow shown in FIG. 15 is realized by the processor 900 executing the extreme end phase control program stored in the memory 901 by the processor 900. Therefore, in the following, details of the extreme phase control flow will be described with reference to FIG.

  In S301 of the endmost phase control flow, it is determined whether or not the endmost phase condition Ce for controlling the rotational phase to the most retarded phase Pr is satisfied. At this time, the endmost phase condition Ce is preset at a timing at which the vehicle can travel even if the torque such as the deceleration condition is small. In S301, while the negative determination is made, the same S301 is repeatedly executed. When the positive determination is made, the process proceeds to S302.

  In S302, the current environmental temperature TP is acquired. At this time, the environmental temperature TP is detected by the temperature sensor 7. In subsequent S303, the stored value corresponding to the environmental temperature TP acquired in S302 is read as the learned value of the most retarded phase Pr stored in the memory 901. In the subsequent S304, the control command value V to be given to the drive source 82 is determined so that the open loop control is performed using the learned value of the most retarded phase Pr read in S103 as the target phase. As a result, the spool 70 moves to the retardation region Rr, so that the rotational phase is controlled to the most retarded phase Pr. After the above, the process returns to S301.

(Endmost phase learning flow)
The extreme end phase learning flow shown in FIG. 16 is realized by the processor 900 executing the extreme end phase learning program stored in the memory 901 by the processor 900. Therefore, in the following, details of the most extreme phase learning flow will be described with reference to FIG.

  In S401 of the endmost phase learning flow, it is determined whether or not the endmost phase condition Ce for controlling the rotational phase to the most retarded phase Pr is satisfied. As a result, while the negative determination is made, S401 is repeatedly executed. When the positive determination is made, the process proceeds to S402.

  In S402, it is determined whether or not the set time te has elapsed since the endmost phase condition Ce was satisfied. At this time, the set time te is preliminarily set to a time required for the rotational phase controlled to the most retarded phase Pr to be stabilized by the contact between the stoppers 151 and 153 after the most end phase condition Ce is satisfied, for example, about 1 second. Is set.

  In subsequent S403, the current environmental temperature TP is acquired. At this time, the environmental temperature TP is detected by the temperature sensor 7. In subsequent S404, the temperature acquired in S403 is set as the environmental temperature TP at the time of the current learning, so that the most retarded phase Pr is learned in correspondence with the environmental temperature TP. At this time, the most retarded phase Pr that is the currently learned value is the actual phase of the rotational phase based on the rotational angles θcra and θcam detected by the sensors 8 and 9. In the subsequent S405, the memory 901 updates the stored value corresponding to the current range Stpt as the temperature range Stp to which the environmental temperature TP at the current learning belongs with the current learned value of the most retarded phase Pr in S404. In addition, after the above, it returns to S401.

  As described so far, the part of the control unit 90 that executes S201 to S217 of the phase difference learning flow corresponds to “phase difference learning means” constructed by the processor 900. Further, the part of the control unit 90 that executes S401 to S405 of the endmost phase learning flow corresponds to “endmost phase learning means” constructed by the processor 900. Further, the part of the control unit 90 that executes S102 to S105 of the lock control flow corresponds to “intermediate phase calculation means” constructed by the processor 900. Furthermore, the portion of the control unit 90 that executes S101 and S106 to S108 of the lock control flow corresponds to “intermediate phase control means” constructed by the processor 900.

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

  According to the first embodiment, when the lock condition Cl is satisfied, an intermediate phase is obtained from the learning value of the reference phase difference MP, which is the phase difference of the intermediate phase Pm with respect to the most retarded phase Pr, and the learned value of the most retarded phase Pr. Pm is calculated, and the rotational phase is controlled to the calculated value of the intermediate phase Pm. Here, since the reference phase difference MP is learned in correspondence with the environmental temperature TP, there is an error in the learning value of the reference phase difference MP and the calculated value of the intermediate phase Pm that depends on it, even if the environmental temperature TP changes. It becomes difficult to occur. According to this, since the rotational phase can be controlled to the intermediate phase Pm that can be calculated with high accuracy, the lock at the intermediate phase Pm can be properly completed.

  Further, any of the phase difference MPc at the time of release execution from the establishment of the release condition Cc to the completion of release and the phase difference MPl at the time of lock execution from the satisfaction of the lock condition Cl to the completion of the lock are either In a situation where one of them becomes unstable, the amount of mutual deviation tends to increase. Therefore, when it is determined that the mutual deviation amount is equal to or less than the allowable amount δMPp, it is based on at least one of the phase difference MPc at release and the phase difference MPl at lock as a stable reference phase difference MP. Thus, the learning value of the reference phase difference MP can be accurately acquired. Here, in particular, the learning value of the reference phase difference MP calculated by the average value of the stable release phase difference MPc and the lock phase difference MPl is such that variation from the normal value can be reduced as much as possible. . According to the above, since it is possible to suppress the occurrence of an error in the calculated value of the intermediate phase Pm that depends on the learning value of the reference phase difference MP, it is possible to properly complete the locking at the intermediate phase Pm.

  Further, regarding the release temperature TPc at the time of release at which the release phase difference MPc is realized and the lock temperature TP1 at the time of lock execution at which the lock phase difference MPl is realized, the environmental temperature TP is between the execution times. As the value changes, the temperature difference increases. Therefore, when it is determined that the temperature difference exceeds the tolerance δTPp, even if the stable release phase difference MPc and the lock phase difference MPl are realized, at least one of the phase differences is realized. Learning of the reference phase difference MP based on it is prohibited. According to this, a situation in which an erroneous reference phase difference MP is learned due to a change in the environmental temperature TP can be avoided, so that an error occurs in the calculated value of the intermediate phase Pm that depends on the learned value of the reference phase difference MP. Can be suppressed. Therefore, this is effective in properly completing the lock at the intermediate phase Pm.

  Furthermore, the learning value of the reference phase difference MP corresponding to each of the plurality of temperature ranges Stp related to the environmental temperature TP is stored in a memory so as to be readable when calculating the intermediate phase Pm. Therefore, since the memory value corresponding to the current range Stpt as the temperature range Stp to which the environmental temperature TP at the current learning belongs is updated in the memory 901 with the current learning value of the reference phase difference MP, the change in the environmental temperature TP can be dealt with in detail. Thus, an accurate reference phase difference MP can be learned. According to this, since the value corresponding to the change in the environmental temperature TP can be calculated with high accuracy as the intermediate phase Pm that depends on the learning value of the reference phase difference MP, the lock at the intermediate phase Pm can be properly completed. Is possible.

  In addition, when the lock condition Cl is satisfied, the rotation is performed to the lock start phase Ps set around the intermediate phase Pm calculated from the learned value of the reference phase difference MP and the learned value of the most retarded phase Pr. After the phase reaches, control of the rotational phase to the intermediate phase Pm is started. Here, as described above, the intermediate phase Pm can be calculated with high accuracy as a value that is unlikely to cause an error. As a result, the lock start phase Ps can be brought as close as possible to the periphery of the intermediate phase Pm. Therefore, by starting the control from the lock start phase Ps to the intermediate phase Pm, the time required to complete the proper lock Can be shortened.

  In addition, by learning not only the reference phase difference MP but also the most retarded phase Pr corresponding to the environmental temperature TP, the intermediate phase Pm calculated from the learning values of these values MP and Pr has the environment The difficulty of generating an error with respect to the change of the temperature TP increases. According to this, since the rotational phase can be controlled to the intermediate phase Pm with increased accuracy, it is effective in properly completing the lock at the intermediate phase Pm.

(Second embodiment)
As shown in FIG. 17, the second embodiment of the present invention is a modification of the first embodiment. In the phase difference learning flow of the second embodiment, S2218 and S2219 are executed after S215. Specifically, in S2218, the stored value of the reference phase difference MP corresponding to the temperature range Stp to which the environmental temperature TP at the time of learning belongs belongs in the memory 901 is read as the last learned value.

  Next, in S2219, the previous learning value read in S2218 is compared with the current learning value of the reference phase difference MP acquired in S215, and whether or not the mutual shift width of these learning values is equal to or larger than the reset width δMPr. Determine whether. At this time, the reset width δMPr is preset to a value of a mutual shift width that makes it uncertain which of the previous learning value and the current learning value, for example, about 5 degrees in terms of crankshaft rotation angle conversion. .

  In the phase difference learning flow of the second embodiment, when a negative determination is made in S2219, the process proceeds to S216 similar to that of the first embodiment, whereas when a positive determination is made in S2219. , The process proceeds to S2220. In S2220, the previous learning value and the current learning value of the reference phase difference MP are reset to the initial value MP0 stored in the memory 901 corresponding to the temperature range Stp to which the environmental temperature TP at the current learning belongs. As a result, the reference phase difference MP stored in the memory 901 is returned to the initial value MP0. In addition, it returns to S201 after S2220 and S216.

  As described above, in the second embodiment, the part of the control unit 90 that executes S201 to S217 and S2218 to S2220 of the phase difference learning flow corresponds to “phase difference learning means” constructed by the processor 900.

  The second embodiment described above is based on the knowledge that it becomes difficult to determine which learning value should be trusted when the mutual deviation width of the previous learning value and the current learning value becomes large with respect to the reference phase difference MP. Is based. Therefore, the initial value MP0 of the reference phase difference MP preset corresponding to the environmental temperature TP is stored in the memory 901, so that the mutual deviation width of the previous learning value and the current learning value is equal to or larger than the reset width δMPr. When the determination is made, these learning values are reset to the stored value MP0. Thereby, when calculating the intermediate phase Pm, it is possible to avoid a situation in which an uncertain learning value is used as the reference phase difference MP, so that it is possible to prevent an error from occurring in the calculated value of the intermediate phase Pm. Therefore, it is possible to properly complete the lock at the intermediate phase Pm.

(Third embodiment)
As shown in FIG. 18, the third embodiment of the present invention is a modification of the first embodiment. In the phase difference learning flow of the third embodiment, S3221 is executed after S216. Specifically, in S3221, the memory value corresponding to the temperature range Stp different from the current range Stpt in the memory 901 is updated with the correction value MPa that depends on the current learning value of the reference phase difference MP acquired in S215. At this time, the correction value MPa is, for example, between the reference phase difference MP of the temperature range Stp to which the environmental temperature TP at the time of learning belongs and the reference phase difference MP of the temperature range Stp different from the temperature TP, for example, Acquired according to a correlation preset by an experiment or the like. After S3221, the process returns to S201.

  As described above, in the third embodiment, the portion of the control unit 90 that executes S201 to S217 and S3221 of the phase difference learning flow corresponds to “phase difference learning means” constructed by the processor 900.

  In the memory 901 of the third embodiment described above, the stored value corresponding to the temperature range Stp different from the current range Stpt is updated with the correction value MPa that depends on the current learning value of the reference phase difference MP. According to this, the update frequency can be increased for the learning value read from the memory 901 when calculating the intermediate phase Pm that is the reference phase difference MP corresponding to each temperature range Stp. Therefore, as the intermediate phase Pm that depends on the learning value of the reference phase difference MP, a value corresponding to the change in the environmental temperature TP can be calculated with high accuracy, which is effective in properly completing the lock at the intermediate phase Pm. Become.

(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.

  Specifically, in Modification 1 regarding the first to third embodiments, S213 is not executed, and S215 is executed regardless of the mutual shift amount between the unlocked phase difference MPc and the locked phase difference MPl. The current learning value of the phase difference MP may be acquired. In the second modification regarding the first to third embodiments, S214 is not executed, and S215 is executed regardless of the temperature difference between the release temperature TPc and the lock temperature TPl, so that the current learning value of the reference phase difference MP is obtained. May be obtained.

  In the third modification related to the first to third embodiments, either one of the release phase difference MPc and the lock phase difference MPl may be acquired as the reference phase difference MP at the current learning in S215. In the modification 4 regarding the first to third embodiments, either one of the release temperature TPc and the lock temperature TPl may be associated with the reference phase difference MP as the environmental temperature TP at the current learning in S215.

  In the modification 5 regarding the first to third embodiments, as shown in FIGS. 19 and 20 (the figure is a modification of the first embodiment), S204, S205, S211, and S212 are not executed, and S213 and S215 are performed. May execute different S1213 and S1215.

  Specifically, in S1213, the release phase Pmc acquired in S202 is compared with the lock phase Pml acquired in S209, and it is determined whether or not the mutual shift amount of these phases is equal to or less than the allowable amount δPmp. To do. At this time, the allowable amount δPmp is preset according to the allowable amount δMPp described in the first embodiment. In S1213, when a negative determination is made, the process proceeds to S217, whereas when a positive determination is made, the process proceeds to S214.

  In S1215, the reference phase difference MP corresponding to the environmental temperature TP is learned based on the phases Pmc and Pml acquired in S202 and S209 as well as the temperatures TPc and TP1 acquired in S203 and S210. . At this time, for example, the difference between the learning value of the most retarded phase Pr read from the memory 901 corresponding to the temperature range Stp to which the average values of the temperatures TPc and TPl belong and the average value of the phases Pmc and Pml is expressed as a reference level. It can be calculated as a learning value of the phase difference MP.

  In the modified example 6 regarding the first to third embodiments, the execution order of S201 to S205 and S206 to S212 may be interchanged. In this case, the timing at which the internal combustion engine is started may be added as the lock condition Cl.

  In the modified example 7 related to the first to third embodiments, at least one temperature range Stp for learning the reference phase difference MP and at least one temperature range Stp for not learning the reference phase difference MP are set within the use temperature range. May be. In this case, the temperature range Stp for learning the reference phase difference MP is set, for example, in a region where the temperature dependence of the reference phase difference MP or the intermediate phase Pm is large.

  In the modification 8 regarding 2nd embodiment, you may employ | adopt the characteristic of 3rd embodiment. That is, as shown in FIG. 21, in the modification 8, after performing S3221 of 3rd embodiment after S216, you may return to S201.

  In the ninth modified example related to the first to third embodiments, the rotation phase may be directly controlled to the intermediate phase Pm at the time of lock execution without setting the lock start phase Ps. In Modification 10 regarding the first to third embodiments, the lock start phase Ps may be set to a constant value regardless of the intermediate phase Pm.

  In the modification 11 regarding the first to third embodiments, at least one temperature range Stp for learning the most retarded phase Pr as the “most end phase” and at least one temperature range Stp for which the same phase Pr is not learned. The temperature may be set within the operating temperature range. In this case, the temperature range Stp for learning the most retarded phase Pr is set, for example, in a region where the temperature dependence of the most retarded phase Pr is large.

  In the modification 12 regarding the first to third embodiments, the most retarded phase Pr as the “most end phase” may be learned without making it correspond to the environmental temperature TP. In Modification 13 regarding the first to third embodiments, the most advanced angle phase may be adopted as the “most end phase”.

  In the modification 14 regarding 1st-3rd embodiment, you may implement | achieve each flow by cooperation of the processor which each some control unit has. That is, “phase difference learning means”, “endmost phase learning means”, “intermediate phase calculation means”, and “lock control means” may be constructed by the cooperation of processors respectively included in a plurality of control units.

  In Modification 15 regarding the first to third embodiments, the restriction hole 166 may not be provided in the lock unit 16. In Modification 16 relating to the first to third embodiments, a lock member that restricts relative rotation of the inner rotor 14 relative to the outer rotor 12 in the advance direction, and a lock that restricts relative rotation of the inner rotor 14 relative to the outer rotor 12 in the retard direction. You may employ | adopt the lock | rock unit 16 which locks a rotation phase by cooperation with a member.

  In the modified example 17 regarding the first to third embodiments, a timing belt may be employed instead of the timing chain 6 as the “torque transmission member”. In the modification 18 regarding the first to third embodiments, the assist unit 17 may not be provided.

  In the modification 19 regarding the first to third embodiments, an electric pump may be adopted as the pump 4 instead of the mechanical pump. In the modified example 20 related to the first to third embodiments, the control valve 60 may be incorporated in one of the inner rotor 14 and the cam shaft 2, or the control valve 60 is disposed outside the inner rotor 14 and the cam shaft 2. May be.

  In addition to the above, in the modified example 21 related to the first to third embodiments, a system for variably controlling the valve timing of the exhaust valve as the “valve”, or the valve timing of both the intake valve and the exhaust valve as the “valve” The present invention may be applied to a system that variably controls the above.

1 valve timing control system, 2 camshaft, 6 timing chain, 11 phase adjustment unit, 12 outer rotor, 14 inner rotor, 15 stopper unit, 16 lock unit, 22 advance chamber, 24 retard chamber, 90 control unit, 150 advance Inner stopper, 151 retard angle inner stopper, 152 advance angle outer stopper, 153 retard angle outer stopper, 164 lock operating chamber, 900 processor, 901 memory, Cc release condition, Cl lock condition, MP reference phase difference, MP0 initial value, MPa Correction value, MPc release phase difference, MPl lock phase difference, Pm intermediate phase, Pr most retarded phase, Ps lock start phase, Stp temperature range, Stpt current range, TP environment temperature, TPc release temperature, TPl lock time Temperature, V control Decree value, DerutaMPp tolerance, DerutaMPr reset width, DerutaTPp tolerance

Claims (9)

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 through a torque transmission member (6) in an internal combustion engine,
An adjustment working chamber (22, 24) is formed between a pair of rotors (12, 14) that rotate in conjunction with the crankshaft and the camshaft, and the crankshaft and the camshaft according to the flow of hydraulic fluid into and out of the adjustment working chamber. A phase adjustment unit (11) for adjusting the rotational phase between the cam shafts;
A stopper unit (15) that has stoppers (150, 151, 152, 153) provided on each of the rotors and regulates the adjustment of the rotational phase exceeding the extreme end phase (Pr) by contact between the stoppers. When,
A lock unit that forms a lock working chamber (164) in the phase adjusting unit and switches between locking and releasing of the rotational phase in an intermediate phase (Pm) deviated from the endmost phase by entering and exiting the working fluid to and from the lock working chamber. (16) and
A control unit (90) for setting a control command value (V) for controlling the entry and exit of hydraulic fluid to and from the adjustment working chamber and the lock working chamber,
When defining a reference phase difference (MP) as a phase difference of the intermediate phase with respect to the extreme end phase,
The control unit is
Phase difference learning means (S201 to S217, S2218 to S2220, S3221) for learning the reference phase difference in correspondence with the environmental temperature (TP);
Endmost phase learning means (S401 to S405) for learning the endmost phase;
Intermediate phase calculating means (S102 to S105) for calculating the intermediate phase from the learned value of the reference phase difference by the phase difference learning means and the learned value of the extreme end phase by the extreme end phase learning means;
Intermediate phase control means for determining the control command value so as to control the rotational phase to the intermediate phase calculated by the intermediate phase calculating means when a lock condition (Cl) for locking the rotational phase is satisfied. (S101, S106 to S108) is constructed by at least one processor (900). The release phase difference (MPc) is defined as the reference phase difference at the time of release execution from when the release condition (Cc) for releasing the lock of the rotational phase is established until the release is completed,
When defining the lock phase difference (MPl) as the reference phase difference at the time of lock execution from when the lock condition is satisfied to when the rotation phase is locked,
The phase difference learning means determines that the phase difference at the time of release and the phase at the time of the lock are determined when it is determined that the mutual shift amount between the phase difference at the time of release and the phase difference at the time of lock is an allowable amount (δMPp) or less. The valve timing control system according to claim 1, wherein the learning value of the reference phase difference is acquired based on at least one of the phase differences.   3. The valve timing control system according to claim 2, wherein the phase difference learning unit calculates the learning value of the reference phase difference based on an average value of the phase difference at release and the phase difference at lock. Define the temperature at release (TPc) as the environmental temperature at the time of release execution,
When the temperature at the time of lock (TPl) is defined as the environmental temperature at the time of the lock execution,
The phase difference learning means prohibits learning of the reference phase difference when it is determined that a temperature difference between the release temperature and the lock temperature exceeds a tolerance (δTPp). The valve timing control system according to claim 2 or 3. A memory (901) for storing an initial value (MP0) of the reference phase difference that is preset according to the environmental temperature;
When the phase difference learning means determines that the mutual shift width between the previous learning value and the current learning value is greater than or equal to the reset width (δMPr) with respect to the reference phase difference, the previous difference learning value and the current learning value The valve timing control system according to any one of claims 1 to 4, wherein a value is reset to the initial value stored in the memory. The control unit is
A memory (901) for storing a learning value of the reference phase difference corresponding to each of a plurality of temperature ranges (Stp) related to the environmental temperature so as to be readable when the intermediate phase is calculated by the intermediate phase calculating unit;
The phase difference learning means updates the stored value corresponding to the current range (Stpt) as the temperature range to which the environmental temperature at the current learning belongs in the memory with the current learned value of the reference phase difference. The valve timing control system according to any one of claims 1 to 5, wherein   The said phase difference learning means updates the stored value corresponding to the current range in the memory with a correction value (MPa) that depends on the current learning value of the reference phase difference. Valve timing control system. When the lock start phase (Ps) is defined as the rotation phase for starting the lock by the lock unit,
When the lock condition is satisfied, the intermediate phase control means causes the intermediate phase after the rotation phase reaches the lock start phase set around the intermediate phase calculated by the intermediate phase calculation means. The valve timing control system according to any one of claims 1 to 7, wherein the control command value is determined so as to start the control of the rotational phase to the front.   The valve timing control system according to any one of claims 1 to 8, wherein the endmost phase learning unit learns the endmost phase in correspondence with the environmental temperature.

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