U.S. patent application number 16/209124 was filed with the patent office on 2019-06-13 for valve timing controller.
This patent application is currently assigned to AISIN SEIKI KABUSHIKI KAISHA. The applicant listed for this patent is AISIN SEIKI KABUSHIKI KAISHA. Invention is credited to Hiroyuki AMANO, Takashi IWAYA, Masaaki KANEKO, Toshiki SATO.
Application Number | 20190178114 16/209124 |
Document ID | / |
Family ID | 66629755 |
Filed Date | 2019-06-13 |
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United States Patent
Application |
20190178114 |
Kind Code |
A1 |
IWAYA; Takashi ; et
al. |
June 13, 2019 |
VALVE TIMING CONTROLLER
Abstract
A valve timing controller includes: a driving side rotation
member synchronously rotating with a crankshaft of an internal
combustion engine; a driven side rotation member contained in the
driving side rotation member and rotating integrally with a cam
shaft for opening and closing a valve coaxially with a rotating
axis of the driving side rotation member; an electromagnetic valve
displacing a relative rotation phase between the driving side and
driven side rotation members by supplying a working fluid to
advancing and retarding chambers defined between the driving side
and driven side rotation members; an intermediate locking mechanism
holding the relative rotation phase in an intermediate locking
phase; a phase detection section detecting the relative rotation
phase; and a control section controlling the electromagnetic valve
based on a detection signal of the phase detection section.
Inventors: |
IWAYA; Takashi; (Obu-shi,
JP) ; KANEKO; Masaaki; (Nukata-gun, JP) ;
SATO; Toshiki; (Takahama-shi, JP) ; AMANO;
Hiroyuki; (Kariya-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AISIN SEIKI KABUSHIKI KAISHA |
Kariya-shi |
|
JP |
|
|
Assignee: |
AISIN SEIKI KABUSHIKI
KAISHA
Kariya-shi
JP
|
Family ID: |
66629755 |
Appl. No.: |
16/209124 |
Filed: |
December 4, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F01L 2250/02 20130101;
F01L 2800/00 20130101; F01L 2001/34433 20130101; F01L 2001/34483
20130101; F01L 2001/34456 20130101; F01L 2001/3443 20130101; F01L
2001/34469 20130101; F01L 2001/34476 20130101; F01L 1/3442
20130101; F01L 2820/041 20130101; F01L 1/356 20130101 |
International
Class: |
F01L 1/356 20060101
F01L001/356; F01L 1/344 20060101 F01L001/344 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 8, 2017 |
JP |
2017-236335 |
Claims
1. A valve timing controller comprising: a driving side rotation
member that synchronously rotates with a crankshaft of an internal
combustion engine; a driven side rotation member that is contained
in the driving side rotation member and rotates integrally with a
cam shaft for opening and closing a valve of the internal
combustion engine coaxially with a rotating axis of the driving
side rotation member; an electromagnetic valve that displaces a
relative rotation phase between the driving side rotation member
and the driven side rotation member by supplying a working fluid to
an advancing chamber and a retarding chamber defined between the
driving side rotation member and the driven side rotation member;
an intermediate locking mechanism that holds the relative rotation
phase in an intermediate locking phase; a phase detection section
that detects the relative rotation phase; and a control section
that controls the electromagnetic valve based on a detection signal
of the phase detection section, wherein the intermediate locking
mechanism includes a first locking mechanism configured with a
first lock member supported by one of the driving side rotation
member and the driven side rotation member, a first lock recess
portion formed on the other one of the driving side rotation member
and the driven side rotation member, and a first biasing member
that biases the first lock member toward the first lock recess
portion, and a second locking mechanism configured with a second
lock member supported by one of the driving side rotation member
and the driven side rotation member, a second lock recess portion
formed on the other one of the driving side rotation member and the
driven side rotation member, and a second biasing member that
biases the second lock member toward the second lock recess
portion, the control section includes a lock releasing control
section that executes a control for causing the electromagnetic
valve to supply the working fluid to the one of the advancing
chamber and the retarding chamber to retract the first lock member
from the first lock recess portion against the biasing force of the
first biasing member and displace the relative rotation phase in a
first direction that becomes an advancing direction or a retarding
direction from the intermediate locking phase, and after the phase
detection section detects that the relative rotation phase exceeds
a sequence region set from the intermediate locking phase to a
predetermined phase in the first direction, executes a control for
causing the electromagnetic valve to supply the working fluid to
the other one of the advancing chamber and the retarding chamber to
retract the second lock member from the second lock recess portion
against a biasing force of the second biasing member, and the lock
releasing control section includes a lock releasing determination
section that determines whether or not a locked state of the
intermediate locking mechanism is released based on a predetermined
determination phase.
2. The valve timing controller according to claim 1, wherein the
determination phase is configured with a first determination phase
set in the first direction from the sequence region and a second
determination phase set in a second direction opposite to the first
direction from the sequence region, in the intermediate locking
mechanism in the locked state, the first lock member is engaged
with the first lock recess portion and the second lock member is
engaged with the second lock recess portion, and the lock releasing
determination section determines that the locked state is released
when the relative rotation phase detected by the phase detection
section is displaced in the second direction and exceeds the second
determination phase after the relative rotation phase is displaced
in the first direction from the intermediate locking phase and
exceeds the first determination phase.
3. The valve timing controller according to claim 1, wherein the
determination phase is configured with a third determination phase
set in the first direction from the sequence region and a fourth
determination phase positioned on a boundary on the first direction
side in the sequence region, in the intermediate locking mechanism
in the locked state, the first lock member is engaged with the
first lock recess portion and the second lock member is engaged
with the second lock recess portion, and the lock releasing
determination section determines that the locked state is released
when a time period until the relative rotation phase detected by
the phase detection section is displaced in the second direction
opposite to the first direction and exceeds the fourth
determination phase after the relative rotation phase is displaced
in the first direction from the intermediate locking phase and
exceeds the third determination phase is longer than a first
predetermined value.
4. The valve timing controller according to claim 1, wherein the
determination phase is configured with a fifth determination phase
set in the first direction from the sequence region, in the
intermediate locking mechanism in the locked state, the first lock
member is engaged with the first lock recess portion and the second
lock member is engaged with the second lock recess portion, and the
lock releasing determination section determines that the locked
state is released when a time period during which the relative
rotation phase detected by the phase detection section is displaced
in the first direction from the intermediate locking phase and is
within a predetermined phase range set before and after the fifth
determination phase is longer than a second predetermined
value.
5. The valve timing controller according to claim 1, further
comprising: a drain flow passage that discharges the working fluid
that acts on the second lock member to cause a lock shift operation
in which the second lock member is engaged with the second lock
recess portion, in a case where the relative rotation phase is set
in the sequence region, wherein the determination phase is
configured with a sixth determination phase set in the second
direction opposite to the first direction from the sequence region
and a seventh determination phase set in the first direction from
the sequence region, in the intermediate locking mechanism in a
state in which the locked state is released, the first lock member
is not engaged with the first lock recess portion and the second
lock member is not engaged with the second lock recess portion, and
the lock releasing determination section determines that the state
is shifted to the locked state when the relative rotation phase is
not displaced in the first direction from the seventh determination
phase and the control for causing the electromagnetic valve to
supply the working fluid to the other one of the advancing chamber
and the retarding chamber is executed in a state where the relative
rotation phase detected by the phase detection section is
positioned in the sequence region after being displaced in the
second direction from the sixth determination phase.
6. The valve timing controller according to claim 3, wherein the
first predetermined value is corrected based on a temperature of
the working fluid.
7. The valve timing controller according to claim 4, wherein the
second predetermined value is corrected based on a temperature of
the working fluid.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and claims priority under 35
U.S.C. .sctn. 119 to Japanese Patent Application 2017-236335, filed
on Dec. 8, 2017, the entire contents of which are incorporated
herein by reference.
TECHNICAL FIELD
[0002] This disclosure relates to a valve timing controller
including a driving side rotation member that rotates synchronously
with a crankshaft, a driven side rotation member that rotates
integrally with a cam shaft for valve opening and closing, and an
intermediate locking mechanism that holds a relative rotation phase
between the driving side rotation member and the driven side
rotation member.
BACKGROUND DISCUSSION
[0003] As a valve timing controller of the above-described
configuration, JP 2013-160095A (Reference 1) discloses a technology
in which an intermediate locking mechanism including a restricting
mechanism and a restraining mechanism is provided, and releasing of
a locked state and shift to the locked state are possible by
setting a relative rotation phase by controlling an electromagnetic
valve based on a detection result by a phase sensor.
[0004] According to the technology described in Reference 1, in a
case where a first lock member of the restricting mechanism reaches
a restriction releasable range after the electromagnetic valve is
set in a retarding position and the restraining mechanism is
released, a second state (state where the locked state by the
restraining mechanism is released) is shifted to a first state
(state where restriction of the restricting mechanism is released)
by a control for switching the electromagnetic valve to the
advancing position. In addition, in a case of the first state, a
control aspect for shifting to the locked state by the control for
switching the electromagnetic valve to the advancing position in a
case where the first lock member reaches a restriction range, is
illustrated.
[0005] As disclosed in Reference 1, a technology in which a shift
to the locked state by the control of the relative rotation phase
between a driving side rotation member and a driven side rotation
member by the electromagnetic valve and a shift to the release of
the locked state is possible, has high convenience since only
assembly of the valve timing controller to an existing oil passage
is necessary without a dedicated lock control valve for controlling
the intermediate locking mechanism or a dedicated oil passage for
releasing the locked state.
[0006] However, the technology described in Reference 1 executes
the control for switching the electromagnetic valve to an advancing
position in a case where the first lock member of the restricting
mechanism has reached the restriction releasable range, but the
first lock member reaches the restriction range without executing
the release of the locked state in a case where a time period
during which the relative rotation phase is within the restriction
releasable range is short. As a result, since the electromagnetic
valve is in the advancing position when the first lock member
reaches the restriction range, there is a concern that the locked
state is unintentionally made.
[0007] In addition, while the vehicle is running, when the
electromagnetic valve is switched to the advancing position while
the relative rotation phase is held within the restriction range
and shifted to the locked state, it is not possible to perform a
control with respect to an advancing phase. Therefore, in a
situation where a position state of the first lock member is
unknown, as long as the relative rotation phase is within the
restriction range, since a lock releasing control, such as
switching the electromagnetic valve to the advancing position after
switching to the retarding position is executed, fuel efficiency or
responsiveness always deteriorates.
[0008] Thus, a need exists for a valve timing controller which is
not susceptible to the drawback mentioned above.
SUMMARY
[0009] A feature of a valve timing controller according to an
aspect of this disclosure resides in that the valve timing
controller includes: a driving side rotation member that
synchronously rotates with a crankshaft of an internal combustion
engine; a driven side rotation member that is contained in the
driving side rotation member and rotates integrally with a cam
shaft for opening and closing a valve of the internal combustion
engine coaxially with a rotating axis of the driving side rotation
member; an electromagnetic valve that displaces a relative rotation
phase between the driving side rotation member and the driven side
rotation member by supplying a working fluid to an advancing
chamber and a retarding chamber defined between the driving side
rotation member and the driven side rotation member; an
intermediate locking mechanism that holds the relative rotation
phase in an intermediate locking phase; a phase detection section
that detects the relative rotation phase; and a control section
that controls the electromagnetic valve based on a detection signal
of the phase detection section, in which the intermediate locking
mechanism includes a first locking mechanism configured with a
first lock member supported by one of the driving side rotation
member and the driven side rotation member, a first lock recess
portion formed on the other one of the driving side rotation member
and the driven side rotation member, and a first biasing member
that biases the first lock member toward the first lock recess
portion, and a second locking mechanism configured with a second
lock member supported by one of the driving side rotation member
and the driven side rotation member, a second lock recess portion
formed on the other one of the driving side rotation member and the
driven side rotation member, and a second biasing member that
biases the second lock member toward the second lock recess
portion, in which the control section includes a lock releasing
control section that executes a control for causing the
electromagnetic valve to supply the working fluid to the one of the
advancing chamber and the retarding chamber to retract the first
lock member from the first lock recess portion against the biasing
force of the first biasing member and displace the relative
rotation phase in a first direction that becomes an advancing
direction or a retarding direction from the intermediate locking
phase, and after the phase detection section detects that the
relative rotation phase exceeds a sequence region set from the
intermediate locking phase to a predetermined phase in the first
direction, executes a control for causing the electromagnetic valve
to supply the working fluid to the other one of the advancing
chamber and the retarding chamber to retract the second lock member
from the second lock recess portion against a biasing force of the
second biasing member, and in which the lock releasing control
section includes a lock releasing determination section that
determines whether or not a locked state of the intermediate
locking mechanism is released based on a predetermined
determination phase.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The foregoing and additional features and characteristics of
this disclosure will become more apparent from the following
detailed description considered with the reference to the
accompanying drawings, wherein:
[0011] FIG. 1 is a configuration view of a valve timing
controller;
[0012] FIG. 2 is a sectional view taken along line II-II in FIG.
1;
[0013] FIG. 3 is a block circuit diagram of a control system;
[0014] FIG. 4 is an image diagram in a locked state of a main
locking mechanism;
[0015] FIG. 5 is an operation image diagram of the locking
mechanism in an intermediate locking phase;
[0016] FIG. 6 is an operation image diagram of the locking
mechanism in a second stop phase;
[0017] FIG. 7 is an operation image diagram of the locking
mechanism in a lock release start phase;
[0018] FIG. 8 is an operation image diagram of the locking
mechanism that started a retarding operation;
[0019] FIG. 9 is an operation image diagram of the locking
mechanism when continuing the retarding operation;
[0020] FIG. 10 is an operation image diagram of the locking
mechanism in a first stop phase;
[0021] FIG. 11 is an operation image diagram of the locking
mechanism that started an advancing operation;
[0022] FIG. 12 is a timing chart illustrating phase displacement in
a lock releasing control;
[0023] FIG. 13 is a flowchart of a lock releasing control according
to a first example;
[0024] FIG. 14 is a timing chart illustrating phase displacement
according to the first example;
[0025] FIG. 15 is a flowchart of a lock releasing control according
to a second example;
[0026] FIG. 16 is a timing chart illustrating phase displacement
according to the second example;
[0027] FIG. 17 is a flowchart of a lock releasing control according
to a third example;
[0028] FIG. 18 is a timing chart illustrating phase displacement
according to the third example;
[0029] FIG. 19 is a flowchart of a lock releasing control according
to a fourth example;
[0030] FIG. 20 is a timing chart illustrating phase displacement
according to the fourth example;
[0031] FIG. 21 is a flowchart of a lock releasing control according
to a fifth example; and
[0032] FIG. 22 is a timing chart illustrating phase displacement
according to the fifth example.
DETAILED DESCRIPTION
[0033] Hereinafter, an embodiment of the disclosure will be
described based on the drawings.
Basic Configuration
[0034] As illustrated in FIGS. 1 to 3, a valve timing control unit
A including an external rotor 20 that serves as a driving side
rotation member, an internal rotor 30 that serves as a driven side
rotation member contained in the external rotor 20, and an
electromagnetic valve 40 that controls hydraulic oil that serves as
a working fluid, is configured. In addition, a valve timing
controller 100 including the valve timing control unit A and a
control section 90 that controls the electromagnetic valve 40, is
configured.
[0035] The internal rotor 30 is connected to an intake cam shaft 5
of an engine E that serves as an internal combustion engine, and
the external rotor 20 is provided so as to be rotatable relative to
the internal rotor 30 coaxially with a rotating axis X of the
intake cam shaft 5. Furthermore, an advancing chamber Ca and a
retarding chamber Cb are formed as a fluid pressure chamber C
therebetween.
[0036] The electromagnetic valve 40 supplies the hydraulic oil to
one of the advancing chamber Ca and retarding chamber Cb and at the
same time, displaces the relative rotation phase (hereinafter,
referred to as relative rotation phase) between the external rotor
20 and the internal rotor 30 around the rotating axis X by
discharging the hydraulic oil from the other one, and a control of
the opening and closing timing of an intake valve 5V is realized by
the displacement. In addition, by controlling the hydraulic oil by
the electromagnetic valve 40, it is possible to realize the shift
to the locked state in an intermediate locking phase M and the lock
releasing for releasing the locked state.
[0037] As illustrated in FIG. 2, when the engine E is in operation,
the entire valve timing control unit A rotates in a driving
rotational direction S. A direction in which the internal rotor 30
is displaced in a direction the same as the driving rotational
direction S with respect to the external rotor 20 is referred to as
an advancing direction Sa, and a direction of displacement opposite
to the advancing direction Sa is referred to as a retarding
direction Sb. Furthermore, the opening and closing timing of the
intake valve 5V is advanced by displacement in the advancing
direction Sa, and the opening and closing timing of the intake
valve 5V is delayed by the displacement in the retarding direction
Sb. In other words, by the displacement in the advancing direction
Sa, a crank angle at the time of opening the intake valve 5V is
displaced in a negative direction from a reference angle, and by
the displacement in the retarding direction Sb, the crank angle at
the time of opening of the intake valve 5V is displaced in a
positive direction from the reference angle.
[0038] The valve timing control unit A includes an intermediate
locking mechanism LU that holds the relative rotation phase in the
intermediate locking phase M illustrated in FIG. 2. The
intermediate locking mechanism LU is configured with a main lock
portion Lm (an example of a second locking mechanism) and an
auxiliary lock portion Ls (an example of a first locking
mechanism), and in an intermediate locking phase M, the members
reach an engaged state at the same time.
[0039] The intermediate locking phase M is a phase in which the
intake valve 5V is set to the opening and closing timing
appropriate for starting the engine E. Therefore, when the engine E
is stopped, the control section 90 performs a control for
displacing the relative rotation phase to the intermediate locking
phase M before stopping the engine E and for setting the
intermediate locking mechanism LU in the locked state. Meanwhile,
when a feedback control is performed with respect to the relative
rotation phase after the start, a control for setting the
intermediate locking mechanism LU to an intermediate lock release
state is performed.
Engine
[0040] The engine E (an example of an internal combustion engine)
illustrated in FIG. 1 is assumed to be provided in a vehicle, such
as a passenger car. The engine E includes a crankshaft 1 in a lower
portion and accommodates a piston 3 in each of the four cylinder
bores of an upper cylinder block 2. By connecting the piston 3 and
the crankshaft 1 to each other with the connecting rod 4, the
engine E is configured in a four-cylinder type. Furthermore, an
upper portion of the engine E is provided with an intake cam shaft
5 for opening and closing the intake valve 5V and an exhaust cam
shaft (not illustrated).
[0041] A timing chain 7 is wound around an output sprocket 6 formed
in the crankshaft 1 of the engine E and a timing sprocket 22S of
the external rotor 20. Furthermore, the sprocket is also provided
at a front end of the exhaust cam shaft on the exhaust side, and a
timing chain 7 is also wound around the sprocket.
[0042] A supply flow passage 8 through which the hydraulic oil is
supplied from a hydraulic pump P driven by the engine E is formed
in an engine configuration member 10 that rotatably supports the
intake cam shaft 5. The hydraulic pump P supplies lubricating oil
stored in the oil pan of the engine E to the electromagnetic valve
40 as the hydraulic oil via the supply flow passage 8.
[0043] Furthermore, in the embodiment, the valve timing control
unit A provided in the intake cam shaft 5 is illustrated, but the
valve timing control unit A may be provided in the exhaust cam
shaft or may be provided in both the intake cam shaft 5 and the
exhaust cam shaft.
Valve Timing Control Unit
[0044] As illustrated in FIGS. 1 and 2, the external rotor 20
includes an external rotor main body 21, a front plate 22, and a
rear plate 23, which are integrated by a plurality of fastening
bolts 24. The above-described timing sprocket 22S is formed at the
outer periphery of the front plate 22. At the inner periphery of
the external rotor main body 21, a plurality (three) of projecting
portions 21T that protrude to an inner side in the radial direction
is integrally formed.
[0045] The internal rotor 30 includes a cylindrical internal rotor
main body 31 that is in tight contact with the projecting portion
21T of the external rotor main body 21 and a plurality (three) of
vane portions 32 that protrude outward in a radial direction from
the outer periphery of the internal rotor main body 31 so as to be
in contact with the inner peripheral surface of the external rotor
main body 21.
[0046] From the configuration, a plurality (three) of fluid
pressure chambers C are formed on the outer peripheral side of the
internal rotor main body 31 at an intermediate position of the
projecting portions 21T adjacent to each other in the rotational
direction, and the fluid pressure chambers C are divided by the
vane portion 32 to define the advancing chamber Ca and the
retarding chamber Cb. Furthermore, a plurality (three) of advancing
flow passages 33 that communicate with the advancing chamber Ca and
a plurality (three) of retarding flow passages 34 that communicate
with the retarding chamber Cb are formed in the internal rotor
30.
[0047] As illustrated in FIG. 1, the front plate 22 is provided
with an intermediate member 9, and a torsion spring 28 for applying
a biasing force between the intermediate member 9 and the external
rotor 20 is provided in the outer peripheral region of the
intermediate member 9. The torsion spring 28 makes the relative
rotation phase act the biasing force in the advancing direction Sa
from the most retarding phase to the intermediate locking phase M,
and assists the displacement in the advancing direction Sa.
Valve Timing Control Unit: Connecting Bolt
[0048] As illustrated in FIG. 1, the connecting bolt 50 includes a
bolt main body 51 which is partly cylindrical, a bolt head portion
52 of the outer end portion, and a male screw portion 53 of the
inner end portion.
[0049] On the inside of the intake cam shaft 5, when an in-shaft
space 5T where a part of the connecting bolt 50 is tightly fitted
is formed, and a female screw portion to which the male screw
portion 53 of the connecting bolt 50 is screwed is formed. The
in-shaft space 5T communicates with the above-described supply flow
passage 8, and the hydraulic oil is supplied from the hydraulic
pump P.
[0050] On the inside of the bolt main body 51, a spool chamber is
formed coaxially with the rotating axis X oriented toward the male
screw portion 53 from the bolt head portion 52, and a spool 41 is
accommodated to be movable in a direction along the rotating axis X
with respect to the spool chamber. The spool 41 supplies and
discharges the hydraulic oil to and from the advancing flow passage
33 and the retarding flow passage 34 by changing the position in
the direction along the rotating axis X. The outer end side (the
direction of the bolt head portion 52) of the spool 41 protrudes
outward by the biasing force of a spool spring (not illustrated),
and a drain hole 41D for discharging the hydraulic oil is formed in
a protrusion end portion thereof.
[0051] In the configuration, by screwing the connecting bolt 50 to
the female screw portion of the intake cam shaft 5 and performing
the connecting operation, the intermediate member 9, the internal
rotor main body 31, and the intake cam shaft 5 are integrated with
each other. In addition, by operating the spool 41 in the direction
along the rotating axis X, it is possible to selectively supply the
hydraulic oil supplied from the hydraulic pump P to the in-shaft
space 5T to the advancing flow passage 33 and the retarding flow
passage 34.
Electromagnetic Valve
[0052] As described above, the electromagnetic valve 40 includes
the spool 41 and an electromagnetic solenoid 44. The
electromagnetic solenoid 44 is provided with a plunger 44a of which
a protrusion amount is controlled by the supplied electric power.
In the electromagnetic valve 40 according to the embodiment, the
electric power amount of the electromagnetic solenoid 44 is
controlled by a known PWM control, that is, based on a duty ratio
(Duty) for modulating a pulse width.
[0053] By operating the plunger 44a, the spool 41 is operated to an
advancing position illustrated in FIG. 1, a neutral position where
the spool 41 is accordingly pushed in only by a predetermined
amount from the advancing position, and a retarding position where
the spool 41 is further pushed in from the neutral position.
[0054] In addition, in the neutral position, the advancing flow
passage 33 and the retarding flow passage 34 are closed, the
hydraulic oil is not supplied to and discharged from the advancing
chamber Ca and the retarding chamber Cb, and the relative rotation
phase is maintained.
[0055] In addition, in the advancing position, the hydraulic oil
from the hydraulic pump P is supplied to the advancing flow passage
33, and at the same time, the hydraulic oil from the retarding flow
passage 34 is discharged via the drain hole 41D of the spool 41.
Accordingly, the relative rotation phase is displaced in the
advancing direction Sa.
[0056] Furthermore, in the retarding position, the hydraulic oil
from the hydraulic pump P is supplied to the retarding flow passage
34, and at the same time, the hydraulic oil from the advancing flow
passage 33 is discharged via the drain hole 41D of the spool 41.
Accordingly, the relative rotation phase is displaced in the
retarding direction Sb.
[0057] Furthermore, in the electromagnetic valve 40, by controlling
the protrusion amount of the plunger 44a, it is also possible to
adjust the amount of the hydraulic oil to be supplied to and
discharged from the advancing chamber Ca and the retarding chamber
Cb.
Intermediate Locking Mechanism: Main Lock Portion
[0058] As illustrated in FIGS. 2 and 4, the main lock portion Lm
(second locking mechanism) has a guide hole 70 formed in one of the
plurality of vane portions 32 in a parallel posture with the
rotating axis X, and at the same time, has a main lock member 71
(an example of a second lock member), a main lock recess portion 72
(an example of a second lock recess portion), and a main lock
spring 73 (an example of a second biasing member).
[0059] The main lock member 71 is slidably inserted into the guide
hole 70. The main lock recess portion 72 is formed in a groove
shape on the rear plate 23 such that an engaging portion 71b of the
main lock member 71 is engaged therewith. The main lock spring 73
is configured as a compression coil type that makes the biasing
force act on the main lock member 71 for engaging the engaging
portion 71b with the main lock recess portion 72.
[0060] The guide hole 70 includes a large-diameter guide hole
portion 70a and a small-diameter guide hole portion 70b having a
smaller diameter than that of the large-diameter guide hole portion
70a. The main lock member 71 is generally columnar and includes a
main body portion 71a accommodated in the large-diameter guide hole
portion 70a of the guide hole 70, an engaging portion 71b
accommodated in the small-diameter guide hole portion 70b with a
smaller diameter than that of the main body portion 71a, and a
shaft-shaped portion 71c having a smaller diameter than that of the
engaging portion 71b at the intermediate position therebetween.
[0061] In the main lock member 71, a first pressure receiving
surface U1 is formed at the end surface of the main body portion
71a between the main body portion 71a and the engaging portion 71b,
and a second pressure receiving surface U2 is formed at the end
portion on the protrusion side of the engaging portion 71b.
[0062] The main lock recess portion 72 has a width slightly wider
than the diameter of the engaging portion 71b and is formed in an
arc-shaped region around the rotating axis X. Accordingly, in the
engaging portion 71b, in a state of being engaged with the main
lock recess portion 72, the displacement of the relative rotation
phase in the main restriction region is possible. In addition, the
main restriction region is a region including a sequence region G
(to be described later) and a lock releasing region F (a region
from an advancing end to the most advancing phase in the sequence
region G).
[0063] In the vane portion 32 in which the guide hole 70 is formed,
a first lock releasing flow passage 75 that communicates with the
small-diameter guide hole portion 70b and a second lock releasing
flow passage 76 that communicates with the large-diameter guide
hole portion 70a are formed.
[0064] As illustrated in FIGS. 5 to 7, the engaging portion 71b has
a lock level J1 that is completely engaged with the main lock
recess portion 72, a lock boundary level J2 immediately after
falling out of the main lock recess portion 72 as illustrated in
FIG. 11, and a lock releasing level J3 which is retracted from the
main lock recess portion 72 further from the lock boundary level J2
as illustrated in FIGS. 9 and 10.
[0065] In a case where the engaging portion 71b is at the lock
level J1, the first lock releasing flow passage 75 communicates
with the first pressure receiving surface U1 (refer to FIG. 5). In
particular, in a case where the engaging portion 71b is in a region
extending from the lock level J1 to the lock boundary level J2, the
second lock releasing flow passage 76 is blocked by the main body
portion 71a and is in a non-communicating state with the first
pressure receiving surface U1 (refer to FIGS. 5 to 8 and refer to
FIG. 11).
[0066] In addition, in a case where the engaging portion 71b is in
the lock releasing level J3, the first lock releasing flow passage
75 communicates with the second pressure receiving surface U2 and
the second lock releasing flow passage 76 communicates with the
first pressure receiving surface U1 (refer to FIGS. 9 and 10).
[0067] The first lock releasing flow passage 75 is configured to be
capable of communicating with a first retarding port 75b via a
first control port 75a that opens toward an inner surface of the
rear plate 23 at a position retracted from the guide hole 70. The
first control port 75a and the first retarding port 75b are formed
in a positional relationship illustrated in FIG. 2.
[0068] The region of the rotation phase extending from the
intermediate locking phase M illustrated in FIG. 5 to the phase
slightly on the advancing side from the phase in FIG. 9 is referred
to as the sequence region G (refer to FIG. 4). In the sequence
region G, the first control port 75a communicates with a drain flow
passage 23D formed on the rear plate 23. In the sequence region G,
since the hydraulic oil that makes the pressure act on the first
pressure receiving surface U1 is discharged from the drain flow
passage 23D, the engaging portion 71b can be engaged with the main
lock recess portion 72 by the biasing force of the main lock spring
73.
[0069] Furthermore, the drain flow passage 23D communicates with
the external space of the rear plate 23, the sequence region G is
an angle region approximately to several degrees (a crank angle of
approximately 10 degrees, from the intermediate locking phase M to
a predetermined phase (for example, -10 degrees) in the advancing
direction Sa).
[0070] The phase obtained by displacing the relative rotation phase
from the advancing end of the sequence region G in the advancing
direction Sa is referred to as the lock releasing region F (refer
to FIG. 4). In the lock releasing region F, since the first
retarding port 75b communicates with a first retarding side groove
23R formed on the rear plate 23, the pressure of the hydraulic oil
supplied to the retarding chamber Cb acts on the first pressure
receiving surface U1, and the main lock member 71 operates in a
direction of retracting from the main lock recess portion 72 (refer
to FIG. 8).
[0071] In the second lock releasing flow passage 76, when the
hydraulic oil is supplied to the retarding flow passage 34, the
hydraulic oil having the same pressure as that of the retarding
flow passage 34 is supplied. From the configuration, the hydraulic
oil can be supplied from the second lock releasing flow passage 76
to the first pressure receiving surface U1 only in a case where the
main lock member 71 is in the lock releasing level J3 illustrated
in FIG. 9.
[0072] Furthermore, as a configuration for supplying the hydraulic
oil to the second lock releasing flow passage 76, it is also
possible to employ a flow passage configuration in which the second
lock releasing flow passage 76 communicates with the retarding flow
passage 34, and a flow passage configuration in which the second
lock releasing flow passage 76 communicates with the retarding
chamber Cb.
[0073] As illustrated in FIG. 10, a lock assist flow passage 22A is
formed in a groove shape on the inner surface of the front plate
22. In a case where the relative rotation phase is displaced in the
retarding direction Sb from the intermediate locking phase M, the
lock assist flow passage 22A communicates with an opening part of
the large-diameter guide hole portion 70a. As illustrated in FIG.
2, the lock assist flow passage 22A communicates with an assist
groove 32a formed in the vane portion 32, and accordingly, a part
of the hydraulic oil is supplied to the large-diameter guide hole
portion 70a, but in order to make it easy to understand, in FIGS. 4
to 11 and the like, the lock assist flow passage 22A is illustrated
as a configuration that can directly communicate with the
large-diameter guide hole portion 70a, and the assist groove 32a is
not illustrated.
[0074] Accordingly, in a case where the relative rotation phase is
displaced to the retarding side from the intermediate locking phase
M, a part of the hydraulic oil supplied to the advancing chamber Ca
is supplied from the lock assist flow passage 22A to the
large-diameter guide hole portion 70a, and assists the engagement
of the main lock member 71 with the main lock recess portion
72.
[0075] Furthermore, as illustrated in FIG. 4, a communication
portion 25 that communicates with the external space is formed in a
hole shape with respect to the front plate 22. In a case where the
relative rotation phase is in the advancing direction Sa from the
intermediate locking phase M, the communication portion 25 makes
the external space communicate with the large-diameter guide hole
portion 70a as being communicated with the opening part of the
large-diameter guide hole portion 70a. As illustrated in FIG. 2,
the communication portion 25 is configured as an opening that
penetrates the front plate 22, and communicates with the
large-diameter guide hole portion 70a via a communication groove
32b formed in the vane portion 32, but in order to make it easy to
understand, in FIGS. 4 to 11 and the like, the communication
portion 25 is illustrated in the form of a groove, and the
communication groove 32b is not illustrated.
[0076] By forming the communication portion 25, when the engaging
portion 71b of the main lock member 71 is engaged with the main
lock recess portion 72, the outside air is suctioned into the
large-diameter guide hole portion 70a, reduces the influence of the
negative pressure, and makes it easy to operate the main lock
member 71.
Locking Mechanism: Auxiliary Lock Portion
[0077] As illustrated in FIG. 2, the auxiliary lock portion Ls (an
example of the first locking mechanism) includes a support hole
portion 80 formed in a posture along a radial direction around one
rotating axis X among the plurality of projecting portions 21T of
the external rotor main body 21, and at the same time, has an
auxiliary lock member 81 (an example of a first lock member), an
auxiliary lock recess portion 82 (an example of a first lock recess
portion), and an auxiliary lock spring 83 (an example of a first
biasing member).
[0078] The auxiliary lock member 81 is slidably inserted into the
support hole portion 80. The auxiliary lock recess portion 82 is
formed in a recessed shape along a peripheral direction on the
outer periphery of the internal rotor main body 31 such that a
restriction end portion 81a of the auxiliary lock member 81 is
engaged therewith. The auxiliary lock spring 83 is configured as a
compression coil type that makes the biasing force for engaging the
restriction end portion 81a with the auxiliary lock recess portion
82 act.
[0079] Accordingly, in a state where the restriction end portion
81a is engaged with the auxiliary lock recess portion 82, it
becomes possible to displace the relative rotation phase in the
auxiliary restriction region (the most retarding phase from the
intermediate locking phase M) along a direction in which the
auxiliary lock recess portion 82 is formed. An auxiliary lock
releasing flow passage 35 communicates with the auxiliary lock
recess portion 82, and the hydraulic oil from the advancing flow
passage 33 is supplied to the auxiliary lock recess portion 82.
[0080] As illustrated in FIG. 5, the main lock member 71 of the
main lock portion Lm is engaged with the main lock recess portion
72, and abuts against the end portion of the main restriction
region of the main lock recess portion 72, and as the auxiliary
lock member 81 of the auxiliary lock portion Ls abuts against the
end portion of the auxiliary restricting region of the auxiliary
lock recess portion 82, the relative rotation phase is locked to
the intermediate locking phase M.
Phase Sensor
[0081] The valve timing controller 100 includes a phase sensor N
(an example of the phase detection section) for detecting the
relative rotation phase between the external rotor 20 and the
internal rotor 30 (refer to FIG. 1). As illustrated in FIG. 3, the
phase sensor N includes a first sensor 11 for detecting rotation of
the crankshaft 1 and a second sensor 12 for detecting rotation of
the intake cam shaft 5.
[0082] The phase sensor N is also used as a cylinder determination
sensor for determining a firing order of the four cylinders at the
time of the start of the engine E. In addition, the phase sensor N
is used as a rotation angle sensor NA (an example of a rotation
angle detection section) that detects the rotation angle of the
intake cam shaft 5, and the second sensor 12 is also used as a
rotation speed sensor that detects a rotation speed of the
crankshaft 1.
[0083] The first sensor 11 includes a first disk 11A rotated
integrally with the crankshaft 1 and made of a magnetic body, such
as an iron material, and a pickup type first proximity sensor
portion 11B that detects multiple first tooth portions 11At formed
at the outer periphery of the first disk 11A. A configuration in
which one cutout portion 11An in which the first tooth portion 11At
does not exist at the outer periphery of the first disk 11A is
formed, and a count value (integrated value) can be acquired by
counting the number of the first tooth portions 11At with reference
to the cutout portion 11An ("0"), is employed.
[0084] The second sensor 12 includes a second disk 12A rotated
integrally with the intake cam shaft 5 (internal rotor 30) and made
of a magnetic body, such as an iron material, and a pickup type
second proximity sensor portion 12B that detects a plurality (four)
of second tooth portions 12At formed at the outer periphery of the
second disk 12A. Furthermore, each peripheral length of the
plurality of second tooth portions 12At is made different in order
to make it possible to determine a cylinder.
[0085] In the configuration, in a case where the relative rotation
phase of the valve timing control unit A is at the reference phase,
when the intake cam shaft 5 rotates, a count value (integrated
value based on a cutout portion 11An) of the first sensor 11 at the
timing of detecting (detecting a down edge) an edge part of four
second tooth portions 12At by the second proximity sensor portion
12B matches a value that corresponds to a reference posture.
[0086] Accordingly, in a case of determining the relative rotation
phase by a phase determination section 91 of the control section
90, it is identified which of the second tooth portions 12At is the
four second tooth portions 12At detected by the second proximity
sensor portion 12B. In addition to the identification, it becomes
possible to acquire the relative rotation phase from the count
value (integrated value based on the cutout portion 11An) of the
detection signal of the first proximity sensor portion 11B at the
timing of detecting the edge of the second tooth portion 12At, and
a difference (offset value) between the reference value (reference
value that corresponds to four second tooth portions 12At) and the
count value.
[0087] Furthermore, since the peripheral lengths of the four second
tooth portions 12At are different from each other, the count value
of the first sensor 11 in a case where the second proximity sensor
portion 12B is in the region where the second tooth portion 12At is
detected is different, and the four second tooth portions 12At are
identified from the count value.
Phase Sensor: Function as Rotation Angle Sensor
[0088] Further, in order to function as the rotation angle sensor
NA, the end portion on the down edge side of the second tooth
portion 12At of the second disk 12A is formed at a position equally
divided by an angle around the rotating axis X into four (divided
at 90 degrees).
[0089] Accordingly, in a case where the intake cam shaft 5 reaches
the reference rotation angle, the count value (the integrated value
with reference to the cutout portion 11An) of the detection signal
of the first proximity sensor portion 11B becomes a value
determined corresponding to the four second tooth portions 12At.
Therefore, in a case of determining the rotation angle of the
intake cam shaft 5 at a predetermined timing, the count value of
the detection signal of the first proximity sensor portion 11B is
acquired, which of the second tooth portions 12At is the count
value is identified, and it becomes possible to determine the
rotation angle from the difference (either positive or negative
value depending on the reference value) between the reference count
value and the acquired count value.
[0090] Furthermore, by counting the detection signal of the first
proximity sensor portion 11B of the first sensor 11 within a unit
time, it is possible to acquire the rotational speed of the
crankshaft 1.
Control Section
[0091] As illustrated in FIG. 3, the control section 90 also has a
function of an engine control unit (ECU) for controlling the engine
E, the detection signals from the phase sensor N that detects the
relative rotation phase and a temperature sensor T that detects the
temperature (basically, water temperature of the cooling water) of
the engine E are input, and a control signal is output to the
electromagnetic solenoid 44 of the electromagnetic valve 40.
[0092] In addition, the control section 90 includes the phase
determination section 91, a rotation angle determination section
92, a phase control section 93, an initial phase setting section
94, a lock shift control section 95, a lock releasing control
section 96, a correction processing section 97, and a table 98.
[0093] The phase determination section 91 determines the relative
rotation phase based on the detection result of the phase sensor N
as described above. By making the phase sensor N function as the
rotation angle sensor NA as described above, the rotation angle
determination section 92 determines the rotation angle of the
intake cam shaft 5 from the detection result of the second sensor
12. The phase control section 93 sets the relative rotation phase
to the target phase.
[0094] When executing the control to shift the intermediate locking
mechanism LU to the locked state by the lock shift control section
95, the initial phase setting section 94 shifts the relative
rotation phase to a preset phase (lock shift start phase K or first
stop phase Q1) (FIG. 8 or 10). The lock shift control section 95
performs a control for shifting the intermediate locking mechanism
LU to the locked state. The lock releasing control section 96
performs a control for releasing the locked state of the
intermediate locking mechanism LU. Although the details will be
described later, the lock releasing control section 96 in the
embodiment includes a lock releasing determination section 96a for
determining whether or not the intermediate locking mechanism LU
releases the locked state based on a predetermined determination
phase.
[0095] The table 98 stores various parameters (a first
determination phase to a seventh determination phase, a
re-determination phase region, a first predetermined value to a
third predetermined value to be described later) at the time of
shifting the intermediate locking mechanism LU to the lock
releasing in the lock releasing control section 96, therein. The
correction processing section 97 performs correction processing
with respect to the various parameters stored in the table 98 based
on the rotational speed of the engine E, the oil temperature, and
the like.
[0096] Furthermore, the phase determination section 91, the
rotation angle determination section 92, the phase control section
93, the initial phase setting section 94, the lock shift control
section 95, the lock releasing control section 96, and the
correction processing section 97 are configured with software, but
may be configured by a combination of hardware, such as logic, and
software.
Lock Releasing
[0097] The operation of releasing the locked state of the
intermediate locking mechanism LU will be described with reference
to FIGS. 5 to 12. In addition, in the following description, the
control for supplying the hydraulic oil to a flow passage system
(advancing flow passage 33, advancing chamber Ca, and the like)
that displaces the relative rotation phase in the advancing
direction Sa is referred to as "advancing operation", and
conversely, the control for supplying the hydraulic oil to a flow
passage system (retarding flow passage 34, retarding chamber Cb,
and the like) that displaces the relative rotation phase in the
retarding direction Sb is referred to as "retarding operation".
[0098] In the embodiment, in a case of releasing the locked state
of the intermediate locking mechanism LU, the control is performed
in order in which the lock releasing control section 96 is operated
in the retarding direction Sb after displacing the relative
rotation phase in the advancing direction Sa. The details thereof
will be described later.
[0099] At the start of the engine E, as illustrated in FIG. 5, the
relative rotation phase is in the locked state restrained to the
intermediate locking phase M (V in FIG. 12). Next, after the start
of the engine E, at the time when reaching the timing of executing
the phase control of the relative rotation phase, the lock
releasing control section 96 executes the advancing operation. In
the advancing operation, the hydraulic oil is supplied from the
advancing flow passage 33 to the advancing chamber Ca, and a part
of the hydraulic oil is supplied to the auxiliary lock releasing
flow passage 35.
[0100] According to the supply, in the auxiliary lock portion Ls,
as illustrated in FIG. 6, the restriction end portion 81a of the
auxiliary lock member 81 is retracted from the auxiliary lock
recess portion 82, the displacement is performed in a state where
the engaging portion 71b is engaged with the main lock recess
portion 72 in the main lock portion Lm, and any phase in the region
from the intermediate locking phase M to the most advancing angle
phase is set.
[0101] In other words, the lock releasing control section 96
executes the advancing operation first, and accordingly, the locked
state of the auxiliary lock portion Ls is released (VI in FIG. 12).
In addition, in a case where the relative rotation phase exceeds
the sequence region G and reaches the lock releasing region F
illustrated in FIG. 7, the advancing operation is stopped (VII in
FIG. 12). In this state, the lock releasing control section 96
stops the advancing operation and executes the control for
supplying the hydraulic oil to the retarding chamber Cb, but since
the retarding chamber Cb is not filled with the hydraulic oil, and
even in a case where the lock releasing region F has been reached
and the lock releasing control section 96 stops the advancing
operation, the relative rotation phase is further displaced in the
advancing direction Sa (VIII in FIG. 12).
[0102] Thereafter, since the hydraulic oil is supplied to the
retarding flow passage 34 by executing the control for supplying
the hydraulic oil to the retarding chamber Cb by the lock releasing
control section 96, the pressure of the hydraulic oil acts on the
first pressure receiving surface U1 from the first lock releasing
flow passage 75 via the first retarding side groove 23R.
Accordingly, the main lock member 71 starts an operation in a lock
releasing direction as illustrated in FIG. 8. Thereafter, the
relative rotation phase is displaced in the retarding direction Sb
as the main lock member 71 moves in the lock releasing direction
and reaches the lock releasing level J3 as illustrated in FIG. 9
(IX in FIG. 12). In the lock releasing level J3, since the lock
boundary level J2 has been exceeded, it becomes possible to supply
the hydraulic oil from the second lock releasing flow passage 76 to
the first pressure receiving surface U1. By continuing the
displacement in the retarding direction Sb, the relative rotation
phase exceeds the intermediate locking phase M in a state where the
main lock member 71 is maintained in the lock releasing level J3,
and at this time, in the auxiliary lock portion Ls, since the
hydraulic oil of the auxiliary lock recess portion 82 is discharged
as the hydraulic oil is discharged from the advancing chamber Ca,
the auxiliary lock member 81 is engaged with the auxiliary lock
recess portion 82 (X in FIGS. 10 and 12). The displacement in the
retarding direction is performed in a range (intermediate locking
phase M to most retarding phase) in which the auxiliary lock member
81 is displaced in a state of being engaged with the auxiliary lock
recess portion 82.
[0103] In this manner, in a case where the lock releasing of the
intermediate locking mechanism LU is appropriately executed, as
illustrated by the solid line in FIG. 12, the relative rotation
phase exceeds the retarding end of the sequence region G, that is,
the intermediate locking phase M. However, in a case where the time
period after the relative rotation phase exceeds the advancing end
of the sequence region G until reaching a state (state in FIG. 9)
where the main lock member 71 reaches the lock releasing level J3
from a state (state in FIG. 7) where the first retarding side
groove 23R and the first lock releasing flow passage 75 communicate
with each other is short, or in a case where the hydraulic oil
pressure that acts on the first pressure receiving surface U1 is
low, the main lock member 71 cannot reach the lock boundary level
J2, and as illustrated by one-dot chain line in FIG. 12, there is a
concern that the lock releasing cannot be executed.
[0104] In addition, even when the lock releasing of the
intermediate locking mechanism LU is appropriately executed, the
advancing operation is performed from the state illustrated in FIG.
10 to the state illustrated in FIG. 11, and there is a case where
the relative rotation phase is held in a second stop phase Q2
included in the sequence region G (X to XI in FIG. 12). As
described above, in the sequence region G, since the hydraulic oil
that makes the pressure act on the first pressure receiving surface
U1 is discharged from the drain flow passage 23D, in a case where
the relative rotation phase is held in the second stop phase Q2,
the main lock member 71 is engaged with the main lock recess
portion 72 by the biasing force of the main lock spring 73 (refer
to FIG. 6). At this time, as illustrated by the broken line in FIG.
12, in a case where the retarding operation is executed from the
second stop phase Q2, since the hydraulic oil is not supplied to
the auxiliary lock releasing flow passage 35, the auxiliary lock
member 81 of the auxiliary lock portion Ls is engaged with the
auxiliary lock recess portion 82, and the locked state in the
intermediate locking phase M is made. Therefore, in a case where
the retarding operation is executed when the relative rotation
phase is in the sequence region G, as illustrated by the solid line
in FIG. 12, the lock releasing control section 96 must execute the
lock releasing control again. As a result, deterioration of fuel
efficiency or deterioration of responsiveness of the valve timing
controller 100 is caused.
[0105] Here, a control method that can reliably release the locked
state in a case where there is a lock release request after the
start of the engine E, or a control method that can remove
inconvenience that the lock releasing control is necessarily
performed in a case where the relative rotation phase is held in
the sequence region G while the vehicle is running after the locked
state is released, is required. Hereinafter, the specific contents
in the lock releasing determination section 96a of the lock
releasing control section 96 used to realize the above-described
control methods will be described below.
Control Method
First Example
[0106] A first example of a determination procedure in the lock
releasing determination section 96a of the lock releasing control
section 96 will be described with reference to FIGS. 13 to 14. The
determination phase used in the lock releasing determination
section 96a in the example is configured with a first determination
phase (for example, a crank angle of -12 degrees from the
intermediate locking phase M) set in the advancing direction Sa (an
example of the first direction) from the sequence region G, and a
second determination phase (for example, a crank angle of +2
degrees from the intermediate locking phase M) set in the retarding
direction Sb (an example in the second direction opposite to the
first direction) from the sequence region G.
[0107] At the start of the engine E, the relative rotation phase is
held in the intermediate locking phase M, and the lock releasing
determination section 96a determines whether or not there is the
lock release request, such as stepping of a driver on an
accelerator pedal (#11 in FIG. 13). In a case where there is the
lock release request (determination of Yes in #11 in FIG. 13), the
lock releasing control section 96 supplies the electric power to
the electromagnetic valve 40 at a duty ratio at which an advancing
operation is performed (refer to #12 in FIG. 13 and FIG. 14). As a
result, the locked state of the auxiliary lock portion Ls is
released, the displacement is performed in a state where the
engaging portion 71b is engaged with the main lock recess portion
72 in the main lock portion Lm, and accordingly, the relative
rotation phase is displaced in the advancing direction Sa from the
intermediate locking phase M (state in FIGS. 5 to 7).
[0108] Next, the lock releasing determination section 96a
determines whether or not the relative rotation phase detected by
the phase sensor N is smaller than the first determination phase
(#13 in FIG. 13). In other words, it is determined whether or not
the relative rotation phase detected by the phase sensor N has
exceeded the first determination phase and further displaced to the
advancing side. In a case where the relative rotation phase is
smaller than the first determination phase (determination of Yes in
#13 in FIG. 13), the lock releasing control section 96 supplies the
electric power to the electromagnetic valve 40 at a duty ratio at
which a retarding operation is performed (refer to #14 in FIG. 13
and FIG. 14). At this time, even in a case where the lock releasing
control section 96 reaches the first determination phase of the
lock release region F and the advancing operation is stopped due to
the fact that the retarding chamber Cb is not filled with the
hydraulic oil or the response delay of the electromagnetic valve
40, after the relative rotation phase is temporarily displaced to
the advancing side, the relative rotation phase is displaced to the
retarding side (refer to FIG. 14). At this time, the hydraulic oil
pressure acts on the first pressure receiving surface U1 from the
first lock releasing flow passage 75 via the first retarding side
groove 23R, and the main lock member 71 starts the operation in the
lock releasing direction (refer to FIGS. 8 to 9).
[0109] Next, the lock releasing determination section 96a
determines whether or not the relative rotation phase detected by
the phase sensor N is greater than the second determination phase
(#15 in FIG. 13). In other words, it is determined whether or not
the relative rotation phase detected by the phase sensor N has
exceeded the second determination phase and further displaced to
the retarding side. In a case where the relative rotation phase is
equal to or less than the second determination phase (determination
of No in #15 in FIG. 13), the lock releasing determination section
96a determines whether or not a predetermined time period has
elapsed after the lock release request appears (or after the
relative rotation phase exceeds the first determination phase) (#16
in FIG. 13). As a result of the determination of #16, in a case
where the predetermined time period has not elapsed, the retarding
operation is continued, and in a case where the predetermined time
period has elapsed, the main lock member 71 has not reached the
lock boundary level J2, that is, it is determined that the locked
state of the intermediate locking mechanism LU is not released and
the lock release sequence is re-executed returning to #12.
[0110] Meanwhile, as a result of the determination in #15, in a
case where the relative rotation phase is greater than the second
determination phase (determination of Yes in #15 in FIG. 13), it is
determined that the locked state of the intermediate locking
mechanism LU is released. In this state, after the main lock member
71 starts the operation in the lock releasing direction, the lock
releasing level J3 has been reached (refer to FIGS. 9 to 10). As
the locked state of the intermediate locking mechanism LU is
released, the phase control section 93 executes the feedback
control such that the relative rotation phase is the target phase
(refer to FIG. 14). Accordingly, it is possible to reliably execute
the lock releasing of the intermediate locking mechanism LU at the
time of the start of the engine E.
Second Example
[0111] A second example of the determination procedure in the lock
releasing determination section 96a of the lock releasing control
section 96 will be described with reference to FIGS. 15 to 16. The
determination phase used in the lock releasing determination
section 96a in the example is configured with a third determination
phase (for example, a crank angle of -13 degrees from the
intermediate locking phase M) set in the advancing direction Sa
from the sequence region G, and a fourth determination phase (for
example, a crank angle of -9 degrees from the intermediate locking
phase M) positioned in the vicinity of the boundary on the
advancing direction Sa side in the sequence region G.
[0112] At the start of the engine E, the relative rotation phase is
held in the intermediate locking phase M, and the lock releasing
determination section 96a determines whether or not there is the
lock release request, such as stepping of the driver on the
accelerator pedal (#21 in FIG. 15). In a case where there is the
lock release request (determination of Yes in #21 in FIG. 15), the
lock releasing control section 96 supplies the electric power to
the electromagnetic valve 40 at a duty ratio at which an advancing
operation is performed (refer to #22 in FIG. 15 and FIG. 16). As a
result, the locked state of the auxiliary lock portion Ls is
released, the displacement is performed in a state where the
engaging portion 71b is engaged with the main lock recess portion
72 in the main lock portion Lm, and accordingly, the relative
rotation phase is displaced in the advancing direction Sa (state in
FIGS. 5 to 7) from the intermediate locking phase M.
[0113] Next, the lock releasing determination section 96a
determines whether or not the relative rotation phase detected by
the phase sensor N is smaller than the third determination phase
(#23 in FIG. 15). In other words, it is determined whether or not
the relative rotation phase detected by the phase sensor N has
exceeded the third determination phase and further displaced to the
advancing side. In a case where the relative rotation phase is
smaller than the third determination phase (determination of Yes in
#23 in FIG. 15), the lock releasing control section 96 starts time
measurement, and at the same time, supplies the electric power to
the electromagnetic valve 40 at a duty ratio at which the retarding
operation is performed (refer to #24 and #25 in FIG. 15 and FIG.
16). At this time, even in a case where the lock releasing control
section 96 reaches the third determination phase of the lock
release region F and the advancing operation is stopped due to the
fact that the retarding chamber Cb is not filled with the hydraulic
oil or the response delay of the electromagnetic valve 40, after
the relative rotation phase is temporarily displaced to the
advancing side, the relative rotation phase is displaced to the
retarding side (refer to FIG. 16). In addition, the hydraulic oil
pressure acts on the first pressure receiving surface U1 from the
first lock releasing flow passage 75 via the first retarding side
groove 23R, and the main lock member 71 starts the operation in the
lock releasing direction (refer to FIGS. 8 to 9).
[0114] Next, the lock releasing determination section 96a
determines whether or not the relative rotation phase detected by
the phase sensor N is greater than the fourth determination phase
(#26 in FIG. 15). In other words, it is determined whether or not
the relative rotation phase detected by the phase sensor N has
exceeded the fourth determination phase and further displaced to
the retarding side (refer to FIG. 16). In a case where the relative
rotation phase is equal to or less than the fourth determination
phase (determination of No in #26 in FIG. 15), the lock releasing
determination section 96a determines whether or not a measured time
period T1 after the relative rotation phase exceeds the third
determination phase exceeds a first predetermined value (for
example, 1 second) (#27 in FIG. 15). As a result of the
determination of #27, in a case where the measured time period T1
does not exceed the first predetermined value, the lock releasing
control section 96 continues the retarding operation (determination
of No in #27 in FIG. 15). Meanwhile, as a result of the
determination in #27, in a case where the measured time period T1
exceeds the first predetermined value (determination of Yes in #27
in FIG. 15), it is determined that the locked state of the
intermediate locking mechanism LU is released. In the state, it is
estimated that the locked state of the intermediate locking
mechanism LU has been released since the retarding operation time
period after the main lock member 71 starts the operation in the
lock releasing direction until reaching the lock releasing level J3
is sufficiently ensured. As the locked state of the intermediate
locking mechanism LU is released, the phase control section 93
executes the feedback control such that the relative rotation phase
is the target phase (refer to FIG. 16).
[0115] Meanwhile, as a result of the determination of #26, in a
case where the relative rotation phase is greater than the fourth
determination phase (determination of Yes in #26 in FIG. 15), the
lock releasing determination section 96a determines whether or not
the measured time period T1 after the relative rotation phase
exceeds the third determination phase exceeds a first predetermined
value (#28 in FIG. 15). As a result of the determination in #28, in
a case where the measured time period T1 exceeds the first
predetermined value (determination of Yes in #28 in FIG. 15), it is
determined that the locked state of the intermediate locking
mechanism LU is released similar to the determination result of Yes
in #27. As a result of the determination of #28, in a case where
the measured time period T1 does not exceed the first predetermined
value (determination of No in #28 in FIG. 15), the retarding
operation time period is not sufficiently ensured. Therefore, the
lock releasing determination section 96a determines that the main
lock member 71 has not reached the lock boundary level J2, that is,
determines that the locked state of the intermediate locking
mechanism LU is not released, the lock releasing control section
96a re-executes the lock release sequence returning to #22.
Accordingly, it is possible to reliably execute the lock releasing
of the intermediate locking mechanism LU at the time of the start
of the engine E.
Third Example
[0116] A third example of the determination procedure in the lock
releasing determination section 96a of the lock releasing control
section 96 will be described with reference to FIGS. 17 to 18. The
determination phase used in the lock releasing determination
section 96a in the example is configured with a fifth determination
phase (for example, a crank angle of -15 degrees from the
intermediate locking phase M) set in the advancing direction Sa
from the sequence region G, and includes a determination phase
region (an example of the predetermined phase range) before and
after (for example, a crank angle of .+-.3 degrees) the fifth
determination phase.
[0117] At the start of the engine E, the relative rotation phase is
held in the intermediate locking phase M, and the lock releasing
determination section 96a determines whether or not there is the
lock release request, such as stepping of the driver on the
accelerator pedal (#31 in FIG. 17). In a case where there is the
lock release request (determination of Yes in #31 in FIG. 17), the
lock releasing control section 96 supplies the electric power to
the electromagnetic valve 40 at a duty ratio at which the relative
rotation phase becomes the phase within the determination phase
region (refer to #32 in FIG. 17 and FIG. 18). At the duty ratio at
which the relative rotation phase becomes a phase within the
determination phase region, the feedback control is performed such
that the relative rotation phase detected by the phase sensor N is
the phase within the determination phase region after the lock
releasing control section 96 is set to the duty ratio at which the
advancing operation is temporarily performed in a case where there
is the lock release request. In other words, as a result of setting
the duty ratio at which the advancing operation is temporarily
performed, the locked state of the auxiliary lock portion Ls is
released, the displacement is performed in a state where the
engaging portion 71b is engaged with the main lock recess portion
72 in the main lock portion Lm, and accordingly, the relative
rotation phase is displaced in the advancing direction Sa from the
intermediate locking phase M (state in FIGS. 5 to 7). After this,
as a result of performing the feedback control such that the
relative rotation phase is the phase within the determination phase
region, the hydraulic oil pressure acts on the first pressure
receiving surface U1 from the first lock releasing flow passage 75
via the first retarding side groove 23R, and the main lock member
71 starts the operation in the lock releasing direction (refer to
FIGS. 8 to 9).
[0118] Next, the lock releasing determination section 96a
determines whether or not a time period T2 during which the
relative rotation phase detected by the phase sensor N is
positioned within the determination phase region is longer than the
second predetermined value (for example, 2 seconds) (#33 in FIG.
17). In a case where the time period T2 during which the relative
rotation phase is positioned within the determination phase region
is longer than the second predetermined value (determination of Yes
in #33 in FIG. 17), it is determined that the locked state of the
intermediate locking mechanism LU is released. In the state, it is
estimated that the locked state of the intermediate locking
mechanism LU has been released since the retarding operation time
period after the main lock member 71 starts the operation in the
lock releasing direction until reaching the lock releasing level J3
is sufficiently ensured. As the locked state of the intermediate
locking mechanism LU is released, the phase control section 93
executes the feedback control such that the relative rotation phase
is the target phase (refer to FIG. 18). Meanwhile, in a case where
the time period T2 during which the relative rotation phase is
positioned within the determination phase region is equal to or
shorter than the second predetermined value (determination of No in
#33 in FIG. 17), the retarding operation time period is not
sufficiently ensured. Therefore, the lock releasing determination
section 96a determines that the main lock member 71 has not reached
the lock boundary level J2, that is, determines that the locked
state of the intermediate locking mechanism LU is not released, and
returning to #32, the lock releasing control section 96 supplies
the electric power to the electromagnetic valve 40 at the duty
ratio at which the relative rotation phase becomes the phase within
the determination phase region. Accordingly, it is possible to
reliably execute the lock releasing of the intermediate locking
mechanism LU at the time of the start of the engine E.
Fourth Example
[0119] A fourth example of the determination procedure in the lock
releasing determination section 96a of the lock releasing control
section 96 will be described with reference to FIGS. 19 to 20. The
determination phase used in the lock releasing determination
section 96a in the example is configured with a fifth determination
phase (for example, a crank angle of -15 degrees from the
intermediate locking phase M) set in the advancing direction Sa
from the sequence region G, and includes a determination phase
region (an example of the predetermined phase range) before and
after (for example, a crank angle of .+-.3 degrees) the fifth
determination phase. Furthermore, in the example, the
re-determination phase region (for example, a crank angle of -11
degrees to .+-.1 degree from the intermediate locking phase M) is
provided on the retarding side from the determination phase
region.
[0120] Since #31 to #33 in FIG. 19 in the example have the same
configurations as those of #31 to #33 in FIG. 17 described in the
third example, #34 and the process after #34 in FIG. 19 will be
described.
[0121] In the lock releasing determination section 96a, in a case
where the time period T2 during which the relative rotation phase
detected by the phase sensor N is positioned within the
determination phase region is longer than the second predetermined
value (determination of Yes in #33 in FIG. 19), further, the
feedback control is executed such that the relative rotation phase
is in the re-determination phase region (#34 in FIG. 19). In other
words, after setting the duty ratio at which the retarding
operation is temporarily performed, the feedback control is
performed such that the relative rotation phase is the
re-determination phase region (refer to FIG. 20). Next, the lock
releasing determination section 96a determines that the locked
state of the intermediate locking mechanism LU is released in a
case where a feedback control time period T3 of the
re-determination phase region becomes longer than the third
predetermined value (for example, 1 second) (determination of Yes
in #35 in FIG. 19). In the example, since the retarding operation
time period in the lock releasing region F can be ensured more than
in the third example, the locked state of the intermediate locking
mechanism LU can be released more reliably. As the locked state of
the intermediate locking mechanism LU is released, the phase
control section 93 executes the feedback control such that the
relative rotation phase is the target phase (refer to FIG. 20).
Fifth Example
[0122] A fifth example of the determination procedure in the lock
releasing determination section 96a of the lock releasing control
section 96 will be described with reference to FIGS. 21 to 22. The
determination phase used in the lock releasing determination
section 96a in the example is configured with a sixth determination
phase (for example, a crank angle of +5 degrees from the
intermediate locking phase M) set in the retarding direction Sb
from the sequence region G, and a seventh determination phase (for
example, a crank angle of -12 degrees from the intermediate locking
phase M) set in the advancing direction Sa from the sequence region
G.
[0123] After the start of the engine E, the lock release
determination as illustrated in the first example to the fourth
example is executed, and the feedback control is executed such that
the relative rotation phase detected by the phase sensor N is the
target phase (#41 and #42 in FIG. 21). Next, the lock releasing
determination section 96a determines whether or not the relative
rotation phase detected by the phase sensor N is greater than the
sixth determination phase (#43 in FIG. 21). In other words, it is
determined whether or not the relative rotation phase detected by
the phase sensor N has exceeded the sixth determination phase and
further displaced to the retarding side.
[0124] As described above, in a case where the relative rotation
phase is on the retarding side from the intermediate locking phase
M, the auxiliary lock member 81 of the auxiliary lock portion Ls is
engaged with the auxiliary lock recess portion 82 and the first
retarding side groove 23R and the first lock releasing flow passage
75 do not communicate with each other. (refer to FIG. 10). When the
advancing operation is performed in this state, a part of the
hydraulic oil supplied to the advancing chamber Ca acts on the main
lock member 71 via the lock assist flow passage 22A and assists the
engagement of the main lock member 71 with the main lock recess
portion 72. Therefore, in a case where the relative rotation phase
is greater than the sixth determination phase (determination of Yes
in #23 in FIG. 21), a determination flag is set to "TRUE" because
the possibility that the main lock member 71 is engaged with the
main lock recess portion 72 is high (refer to #44 in FIG. 21 and
FIG. 22).
[0125] Next, the lock releasing determination section 96a
determines whether or not the relative rotation phase detected by
the phase sensor N is smaller than the seventh determination phase
(#45 in FIG. 21). As described above, in the sequence region G,
since the first control port 75a communicates with the drain flow
passage 23D formed on the rear plate 23, the hydraulic oil that
makes the pressure act on the first pressure receiving surface U1
is discharged from the drain flow passage 23D, and the possibility
that the main lock member 71 is engaged with the main lock recess
portion 72 by the biasing force of the main lock spring 73 is high.
Meanwhile, as a result of the determination of #45, in a case where
the relative rotation phase detected by the phase sensor N is
smaller than the seventh determination phase (determination of Yes
in #45 in FIG. 21), the main lock member 71 is not engaged with the
main lock recess portion 72 and passes through the sequence region
G, and thus, the determination flag is set to "FALSE" (refer to #46
in FIG. 21 and FIG. 22).
[0126] Next, the lock releasing determination section 96a
determines whether or not all of three conditions, such as (1) a
condition that that the relative rotation phase is positioned in
the sequence region G, (2) a condition that the retarding operation
is executed for making the target phase is in the retarding
direction Sb, and (3) a condition that the determination flag is
"TRUE", are satisfied after the relative rotation phase detected by
the phase sensor N is displaced in the advancing direction Sa from
the sixth determination phase (#47 in FIG. 21). In other words, in
a case where the relative rotation phase does not exceed the
seventh determination phase and is held in the sequence region G,
there is a high possibility that the main lock member 71 is engaged
with the main lock recess portion 72, the first retarding side
groove 23R and the first lock releasing flow passage 75 do not
communicate with each other in the sequence region G, and thus, the
locked state of the intermediate locking mechanism LU is not
released even when the retarding operation is performed (refer to
FIG. 6). Therefore, in a case where the determination condition of
#47 is satisfied (determination of Yes in #47 in FIG. 21), the lock
releasing sequence as illustrated in Examples 1 to 4 is executed
(refer to #48 in FIG. 21 and FIG. 22). Meanwhile, in a case where
the determination condition of #47 is not satisfied (determination
of No in #47 in FIG. 21), it is determined that the locked state of
the intermediate locking mechanism LU is released, and the feedback
control is executed such that the relative rotation phase is the
target phase returning to #42. In this manner, since it is not
necessary to execute the lock releasing sequence in a case where
the retarding operation is performed when the relative rotation
phase is in the sequence region G, there is no inconvenience caused
by deterioration of fuel efficiency or responsiveness of the valve
timing controller 100.
Another Embodiment
[0127] The disclosure may be configured as follows in addition to
the above-described embodiments.
[0128] (a) Various parameters (the first determination phase to the
seventh determination phase, the re-determination phase region, the
first predetermined value to the third predetermined value) in the
above-described first to fifth examples may be corrected for each
predetermined time by the correction processing section 97. In this
case, for example, in a case where the oil temperature of the
hydraulic oil is low and the viscosity is high, it requires to take
time to release the locked state, and thus, it is considered that
the first predetermined value to the third predetermined value
increase as the oil temperature of the hydraulic oil decreases.
[0129] (b) The electromagnetic valve may be provided on the outside
of the valve timing control unit A as a working fluid control
mechanism. In this configuration, it is also possible to simplify
the configuration of the flow passage compared to the configuration
in which the electromagnetic valve is provided on the inside of the
valve timing control unit A.
[0130] (c) The main lock member 71 may be configured to protrude
outward in the radial direction as a modification example of the
configuration in which the main lock portion Lm is provided in the
vane portion 32. Further, as the auxiliary lock portion Ls, the
auxiliary lock member 81 may be configured to move back and forth
along the axis parallel to the rotating axis X. The configuration
of the main lock portion Lm and the auxiliary lock portion Ls is
any configuration.
[0131] (d) The sequence region G is formed on the retarding side
with reference to the locking phase (intermediate locking phase M)
contrary to the embodiment. In this case, "retarding" and
"advancing" are replaced by opposite terms, the above-described
first direction becomes the retarding direction Sb, and the second
direction becomes the advancing direction Sa. In this manner, even
in a case where the sequence region G is set in this manner, it is
possible to execute the lock releasing by the same control.
[0132] The disclosure can be used for a valve timing controller
including an intermediate locking mechanism for holding the
relative rotation phase between the driving side rotation member
and the driven side rotation member.
[0133] A feature of a valve timing controller according to an
aspect of this disclosure resides in that the valve timing
controller includes: a driving side rotation member that
synchronously rotates with a crankshaft of an internal combustion
engine; a driven side rotation member that is contained in the
driving side rotation member and rotates integrally with a cam
shaft for opening and closing a valve of the internal combustion
engine coaxially with a rotating axis of the driving side rotation
member; an electromagnetic valve that displaces a relative rotation
phase between the driving side rotation member and the driven side
rotation member by supplying a working fluid to an advancing
chamber and a retarding chamber defined between the driving side
rotation member and the driven side rotation member; an
intermediate locking mechanism that holds the relative rotation
phase in an intermediate locking phase; a phase detection section
that detects the relative rotation phase; and a control section
that controls the electromagnetic valve based on a detection signal
of the phase detection section, in which the intermediate locking
mechanism includes a first locking mechanism configured with a
first lock member supported by one of the driving side rotation
member and the driven side rotation member, a first lock recess
portion formed on the other one of the driving side rotation member
and the driven side rotation member, and a first biasing member
that biases the first lock member toward the first lock recess
portion, and a second locking mechanism configured with a second
lock member supported by one of the driving side rotation member
and the driven side rotation member, a second lock recess portion
formed on the other one of the driving side rotation member and the
driven side rotation member, and a second biasing member that
biases the second lock member toward the second lock recess
portion, in which the control section includes a lock releasing
control section that executes a control for causing the
electromagnetic valve to supply the working fluid to the one of the
advancing chamber and the retarding chamber to retract the first
lock member from the first lock recess portion against the biasing
force of the first biasing member and displace the relative
rotation phase in a first direction that becomes an advancing
direction or a retarding direction from the intermediate locking
phase, and after the phase detection section detects that the
relative rotation phase exceeds a sequence region set from the
intermediate locking phase to a predetermined phase in the first
direction, executes a control for causing the electromagnetic valve
to supply the working fluid to the other one of the advancing
chamber and the retarding chamber to retract the second lock member
from the second lock recess portion against a biasing force of the
second biasing member, and in which the lock releasing control
section includes a lock releasing determination section that
determines whether or not a locked state of the intermediate
locking mechanism is released based on a predetermined
determination phase.
[0134] In this configuration, the intermediate locking mechanism is
configured with the first locking mechanism and the second locking
mechanism, and for example, the electromagnetic valve is set in the
advancing position and releases the locked state of the first
locking mechanism, the electromagnetic valve is switched to the
retarding position after the relative rotation phase exceeds the
sequence region, and the locked state of the second locking
mechanism is released. Therefore, it is possible to release the
locked state of the intermediate locking mechanism while
configuring to switch the electromagnetic valve to advancing and
retarding positions and to supply the working fluid to the existing
flow passage. As a result, only assembly of the valve timing
controller to the existing oil passage is necessary without a
dedicated lock control valve for controlling the intermediate
locking mechanism or a dedicated oil passage for releasing the
locked state.
[0135] Furthermore, since the lock releasing determination section
of the configuration determines whether or not the locked state is
released based on a predetermined determination phase, it is
possible to reliably execute the lock releasing. In addition, while
the vehicle is running, even in a situation where a position state
of the second lock member is unknown, the lock releasing control
may be executed only when it is determined that the locked state
has not been released by the lock releasing determination section,
it is possible to suppress inconvenience caused by deterioration of
fuel efficiency or responsiveness. Therefore, a valve timing
controller that can efficiently perform the lock release
determination while having a configuration that does not require a
dedicated lock control valve or a dedicated oil passage for
releasing the locked state, is configured.
[0136] As another configuration, the valve timing controller may be
configured such that the determination phase is configured with a
first determination phase set in the first direction from the
sequence region and a second determination phase set in a second
direction opposite to the first direction from the sequence region,
in the intermediate locking mechanism in the locked state, the
first lock member is engaged with the first lock recess portion and
the second lock member is engaged with the second lock recess
portion, and the lock releasing determination section determines
that the locked state is released when the relative rotation phase
detected by the phase detection section is displaced in the second
direction and exceeds the second determination phase after the
relative rotation phase is displaced in the first direction from
the intermediate locking phase and exceeds the first determination
phase.
[0137] In this configuration, for example, in a case where the
first direction is the advancing direction and the second direction
is the retarding direction, based on the first determination phase
set on an advancing side from the sequence region and the second
determination phase set on a retarding side from the sequence
region, the lock release determination is executed. In other words,
it is possible to determine that the locked state of the first
locking mechanism is released by the first determination phase by
setting the electromagnetic valve to the advancing position, and it
is possible to determine that the locked state of the second
locking mechanism is released by the second determination phase by
switching the electromagnetic valve to the retarding position.
[0138] As another configuration, the valve timing controller may be
configured such that the determination phase is configured with a
third determination phase set in the first direction from the
sequence region and a fourth determination phase positioned on a
boundary on the first direction side in the sequence region, in the
intermediate locking mechanism in the locked state, the first lock
member is engaged with the first lock recess portion and the second
lock member is engaged with the second lock recess portion, and the
lock releasing determination section determines that the locked
state is released when a time period until the relative rotation
phase detected by the phase detection section is displaced in the
second direction opposite to the first direction and exceeds the
fourth determination phase after the relative rotation phase is
displaced in the first direction from the intermediate locking
phase and exceeds the third determination phase is longer than a
first predetermined value.
[0139] In this configuration, for example, in a case where the
first direction is the advancing direction and the second direction
is the retarding direction, based on the third determination phase
set on the advancing side from the sequence region and the fourth
determination phase positioned on the boundary on the advancing
side in the sequence region, the lock release determination is
executed. In other words, when the time period from exceeding the
third determination phase to exceeding the fourth determination
phase is longer than the first predetermined value, until the
relative rotation phase exceeds the sequence region and returns to
the sequence region again, the electromagnetic valve can
sufficiently ensure the time period during which the
electromagnetic valve is in the retarding position. Accordingly,
the locked state of the second locking mechanism is reliably
released.
[0140] As another configuration, the valve timing controller may be
configured such that the determination phase is configured with a
fifth determination phase set in the first direction from the
sequence region, in the intermediate locking mechanism in the
locked state, the first lock member is engaged with the first lock
recess portion and the second lock member is engaged with the
second lock recess portion, and the lock releasing determination
section determines that the locked state is released when a time
period during which the relative rotation phase detected by the
phase detection section is displaced in the first direction from
the intermediate locking phase and is within a predetermined phase
range set before and after the fifth determination phase is longer
than a second predetermined value.
[0141] In this configuration, for example, in a case where the
first direction is the advancing direction, based on the fifth
determination phase set on the advancing side from the sequence
region, the lock release determination is executed. In other words,
when the time period during which the phase is within the
predetermined phase range set before and after the fifth
determination phase is longer than the second predetermined value,
until the relative rotation phase exceeds the sequence region and
returns to the sequence region again, the electromagnetic valve can
sufficiently ensure the time period during which the
electromagnetic valve is in the retarding position. Accordingly,
the locked state of the second locking mechanism is reliably
released.
[0142] As another configuration, the valve timing controller may be
configured such that the valve timing controller further includes a
drain flow passage that discharges the working fluid that acts on
the second lock member to cause a lock shift operation in which the
second lock member is engaged with the second lock recess portion,
in a case where the relative rotation phase is set in the sequence
region, the determination phase is configured with a sixth
determination phase set in the second direction opposite to the
first direction from the sequence region and a seventh
determination phase set in the first direction from the sequence
region, in the intermediate locking mechanism in a state in which
the locked state is released, the first lock member is not engaged
with the first lock recess portion and the second lock member is
not engaged with the second lock recess portion, and the lock
releasing determination section determines that the state is
shifted to the locked state when the relative rotation phase is not
displaced in the first direction from the seventh determination
phase and the control for causing the electromagnetic valve to
supply the working fluid to the other one of the advancing chamber
and the retarding chamber is executed in a state where the relative
rotation phase detected by the phase detection section is
positioned in the sequence region after being displaced in the
second direction from the sixth determination phase.
[0143] In this configuration, for example, in a case where the
first direction is the advancing direction and the second direction
is the retarding direction, based on the sixth determination phase
set on the retarding side from the sequence region and the seventh
determination phase set on a advancing side from the sequence
region, the lock release determination is executed, and in the
sequence region, the working fluid that acts on the second lock
member is discharged from the drain flow passage. In other words,
while the vehicle is running, after the relative rotation phase is
displaced in the retarding direction from the sixth determination
phase set on the retarding side from the sequence region, as the
relative rotation phase is controlled in the advancing direction,
and accordingly, the second lock member is engaged with the second
lock recess portion entering the sequence region. In addition, when
the first lock member is engaged with the first lock recess
portion, the locked state is made, but when the relative rotation
phase is displaced to the advancing side from the seventh
determination phase set on the advancing side from the sequence
region, the locked state is not made. Meanwhile, when the relative
rotation phase has not displaced to the advancing side from the
seventh determination phase, the probability of the locked state is
high.
[0144] Here, as in this configuration, when the relative rotation
phase is not displaced in the advancing direction from the seventh
determination phase and the electromagnetic valve executes the
control for supplying the working fluid to the retarding chamber,
there is a probability that the first lock member is engaged with
the first lock recess portion, and thus, it is determined that the
locked state has not been released and the lock releasing control
is executed again. Conversely, even in a case where the relative
rotation phase is in the sequence region, when the relative
rotation phase is not displaced in the retarding direction from the
sixth determination phase or when the relative rotation phase is
displaced in the advancing direction from the seventh determination
phase, it is determined that the locked state has been released.
Therefore, in a case where a retarding control from the sequence
region is performed, it is not necessary to perform the lock
releasing control, and thus, there is no inconvenience caused by
deterioration of fuel efficiency or responsiveness.
[0145] As another configuration, the valve timing controller may be
configured such that the first predetermined value is corrected
based on a temperature of the working fluid.
[0146] As another configuration, the valve timing controller may be
configured such that the second predetermined value is corrected
based on a temperature of the working fluid.
[0147] In the configuration, the first predetermined value (second
predetermined value) is corrected based on a temperature of the
working fluid. In other words, in a case where the working fluid is
engine oil that is a viscous fluid, the viscosity of the engine oil
increases as the temperature decreases, and it takes time to
release the locked state. Therefore, by correcting the first
predetermined value (second predetermined value), the locked state
is reliably released regardless of the viscosity.
[0148] The principles, preferred embodiment and mode of operation
of the present invention have been described in the foregoing
specification. However, the invention which is intended to be
protected is not to be construed as limited to the particular
embodiments disclosed. Further, the embodiments described herein
are to be regarded as illustrative rather than restrictive.
Variations and changes may be made by others, and equivalents
employed, without departing from the spirit of the present
invention. Accordingly, it is expressly intended that all such
variations, changes and equivalents which fall within the spirit
and scope of the present invention as defined in the claims, be
embraced thereby.
* * * * *