TECHNICAL FIELD
[0001] The present invention relates to a valve opening and closing timing control device
that controls a relative rotational phase of a driven-side rotary member rotating
integrally with a camshaft of an internal combustion engine relative to a driving-side
rotary member rotating synchronously with a crankshaft of the internal combustion
engine.
BACKGROUND ART
[0002] Conventionally, a valve opening and closing timing control device controlling the
opening and closing timing of one of or both of an intake valve and an exhaust valve
has been used in order to enhance a fuel consumption of an internal combustion engine
(hereinafter referred to as an engine). This kind of valve opening and closing timing
control device controls the opening and closing timing by changing a relative rotational
phase between a driving-side rotary member rotating synchronously with a crankshaft
and a driven-side rotary member rotating integrally with a camshaft.
[0003] Generally, an optimum opening and closing timing of each of the intake valve and
the exhaust valve differs in accordance with an operation condition of the engine,
for example, when the engine starts and when a vehicle runs. When the engine starts,
the optimum opening and closing timing of each of the intake valve and the exhaust
valve for starting the engine is realized by locking the relative rotational phase
of the driven-side rotary member relative to the rotation of the driving-side rotary
member (hereinafter referred to as a relative rotational phase) at a predetermined
phase that is provided between a most retard phase and a most advance phase. However,
when the vehicle idles after starting the engine, because an amount of emission of
carbon hydride (HC) is increased in a case where the relative rotational phase is
maintained at a phase being positioned when the engine starts, it is favorable that
the relative rotational phase is changed to a phase where the amount of emission of
HC can be inhibited from being generated when the vehicle idles after starting the
engine. In addition, it is favorable that the relative rotational phase is changed
so as to easily restart the engine that is in a high-temperature state when the vehicle
performs an idling stop in which the engine is temporarily stopped in a case where
the vehicle stops by an operation of a brake pedal during a normal operation. Such
a technology is described in Patent document 1 of which a source is shown below.
[0004] In Patent document 1, a variable valve timing control device of an internal combustion
engine including a feature that locks a rotational phase of a camshaft relative to
a crankshaft of the internal combustion engine at an intermediate locked phase being
positioned at a substantially middle of an adjustable range of the rotational phase
is disclosed. The variable timing control device of the internal combustion engine
includes a lock control portion that controls an oil-pressure control device in order
to lock the rotational phase of the camshaft at the intermediate locked phase by a
lock pin when a lock request is generated. The lock control portion controls the oil-pressure
control device so that the rotational phase of the camshaft passes through the intermediate
locked phase while biasing the lock pin in a lock direction when the lock request
is generated. When the rotational phase of the camshaft does not move at the vicinity
of the intermediate locked phase during the phase variable control, a control amount
of the oil-pressure control device is changed further by a predetermined amount in
a moving direction of the rotational phase of the camshaft. In this case, it is determined
that the locking is completed in a case where the rotational phase of the camshaft
does not move.
DOCUMENT OF PRIOR ART
PATENT DOCUMENT
OVERVIEW OF INVENTION
PROBLEM TO BE SOLVED BY INVENTION
[0006] The technology described in Patent document 1 controls the rotational phase of the
camshaft to pass through the intermediate locked phase when the lock request is generated.
In addition, after the control, the control amount of the oil-pressure control device
is further changed to the predetermined amount in the moving direction of the rotational
phase of the camshaft when the rotational phase of the camshaft does not move at vicinity
of the intermediate locked phase. In a case where the rotational phase of the camshaft
does not move further, it is determined that the locking is completed. Thus, the rotational
phase of the camshaft may pass through the intermediate locked phase, and in such
a case, it takes some time to complete the locking.
[0007] The object of the present invention is, in a view of an aforementioned problem, to
provide a valve opening and closing timing control device that can promptly move a
relative rotational phase of a driven-side rotary member relative to a driving-side
rotary member to an intermediate locked phase.
MEANS FOR SOLVING PROBLEM
[0008] A valve opening and closing timing control device of this invention for achieving
the above-mentioned purpose includes a driving-side rotary member rotating synchronously
with a crankshaft of an internal combustion engine, a driven-side rotary member rotating
integrally with a camshaft of the internal combustion engine, the driven-side rotary
member being relatively rotatable with the driving-side rotary member, a fluid pressure
chamber being formed with the driving-side rotary member and the driven-side rotary
member, a vane being positioned within the fluid pressure chamber, the vane dividing
the fluid pressure chamber into a retard chamber and an advance chamber that each
allows an inflow and an outflow of a fluid, the vane selectively moving a relative
rotational phase of the driven-side rotary member relative to the driving-side rotary
member between a retarded direction and an advance direction, the retarded direction
where a volume within the retard chamber increases by the inflow of the fluid, the
advance direction where a volume within the advance chamber increases by the inflow
of the fluid, an intermediate lock mechanism being provided at one of the driving-side
rotary member and the driven-side rotary member, the intermediate lock mechanism including
a lock member being movable relative to the other of the driving-side rotary member
and the driven-side rotary member, the intermediate lock mechanism including a recess
extending along a circumferential direction, the recess being provided at the other
of the driving-side rotary member and the driven-side rotary member, the intermediate
lock mechanism being switchable between a lock state and an unlock state, the lock
state where the relative rotational phase is locked at an intermediate locked phase
being positioned between a most advance phase and a most retard phase by a fitting
of the lock member into the recess, the unlocked state where the relative rotational
phase is unlocked by a retraction of the lock member from the recess, and a phase
control portion performing a control of a supply of the fluid to the retard chamber
and a discharge of the fluid from the advance chamber, or a control of a discharge
of the fluid from the retard chamber and a supply of the fluid to the advance chamber,
in order for the lock member to reach the intermediate locked phase by reducing a
travelling speed of the relative rotational phase from a reference phase that is provided
between a present phase and the intermediate locked phase to the intermediate locked
phase to be slower than the travelling speed of the relative rotational phase to the
reference phase when the intermediate lock mechanism is switched from the unlock state
to the lock state.
[0009] As in the present construction, the relative rotational phase of the driven-side
rotary member relative to the driving-side rotary member can be in a lock state securely
while promptly moving to the reference phase without jumping over the intermediate
locked phase. Thus, the relative rotational phase can promptly move to the intermediate
locked phase.
[0010] Furthermore, it is favorable that the phase control portion performs one of the control
of the supply of the fluid to the retard chamber and the discharge of the fluid from
the advance chamber, and the control of the discharge of the fluid from the retard
chamber and the supply of the fluid to the advance chamber, in order for the travelling
speed of the relative rotational phase from the present phase to the intermediate
locked phase to be reduced by a predetermined amount of change.
[0011] As in the present construction, because the travelling time from the current phase
to the intermediate locked phase can be easily predicted, a next operation can be
efficiently followed.
[0012] Furthermore, it is favorable that the phase control portion performs one of the control
of the supply of the fluid to the retard chamber and the discharge of the fluid from
the advance chamber, and the control of the discharge of the fluid from the retard
chamber and the supply of the fluid to the advance chamber, based on a map defined
by a relationship between the travelling speed of the relative rotational phase from
the present phase to the intermediate locked phase and a quantity of state showing
a state of the fluid flowed to the retard chamber and to the advance chamber.
[0013] The easiness of the flow of the fluid in a case where the fluid passes through the
flow passage changes in accordance with, for example, the pressure level and the temperature
level of the fluid. Thus, a map defining the quantity of state and the travelling
speed is memorized while the pressure level and the temperature level of the fluid
serves as the amount of the state showing the state of the fluid. Thus, because the
phase control portion controls the supply and discharge based on the map, the phase
control position can easily move the relative rotational phase to the intermediate
locked phase promptly.
[0014] In addition, it is favorable that the valve opening and closing timing control device
further includes a determination portion determining whether the lock member reaches
a determination phase, the determination phase being provided between the intermediate
locked phase and the reference phase, and the determination portion determines whether
the lock member reaches the determination phase when the phase control portion controls
the lock member to move to the determination phase after performing one of the control
of the supply of the fluid to the retard chamber and the discharge of the fluid from
the advance chamber, and the control of the discharge of the fluid from the retard
chamber and the supply of the fluid to the advance chamber.
[0015] According to the construction, because the position between the intermediate locked
phase and the determination phase can be shallow, the determination portion securely
determines whether the lock member reaches the intermediate locked phase.
[0016] In addition, it is favorable that the relative rotational phase moves from the present
phase to the reference phase based on a first travelling speed, and the relative rotational
phase moves from the reference phase to the intermediate locked phase based on a second
travelling speed that is slower than the first travelling speed.
[0017] According to the construction, because the travelling speed of the relative rotational
phase is reduced in a case where the relative rotational phase moves from the reference
phase to the intermediate locked phase after moving from the present phase to the
reference phase, the relative rotational phase can be prevented from passing through
the intermediate locked phase. Accordingly, the relative rotational phase can move
promptly and securely from the present phase to the intermediate locked phase without
passing through the intermediate locked phase.
BRIEF DESCRIPTION OF DRAWINGS
[0018]
[Fig. 1] is a cross sectional view of a valve opening and closing timing control device.
[Fig. 2] is a cross sectional view illustrating a lock state taken along line II-II
in Fig. 1.
[Fig. 3] is a cross sectional view illustrating an unlock state taken along line II-II
in Fig. 1.
[Fig. 4] is a cross sectional view illustrating a most retard phase state taken along
line II-II in Fig. 1.
[Fig. 5] is a view schematically illustrating a reference phase in a case where a
relative rotational phase moves from a present position to an intermediate locked
phase along an advance direction.
[Fig. 6] is a view schematically illustrating a reference phase in a case where the
relative rotational phase moves from the present position to the intermediate locked
phase along a retarded direction.
[Fig. 7] is a view illustrating an example of a travelling speed in a case where an
inner rotor relative to an outer rotor relatively rotates from the present phase to
the intermediate locked phase.
[Fig. 8] is a view illustrating another example of a travelling speed in a case where
the inner rotor relative to an outer rotor relatively rotates from the present phase
to the intermediate locked phase.
MODE FOR CARRYING OUT THE INVENTION
[0019] A valve opening and closing timing control device according to the present invention
is able to move a lock member promptly to an intermediate locked phase in a case where
a relative rotational phase of a driven-side rotary member relative to a driving-side
rotary member comes to be the intermediate locked phase. Hereinafter, a valve opening
and closing timing control device 1 of a present embodiment will be explained in detail.
Fig. 1 is a side cross sectional view illustrating a whole configuration of the valve
opening and closing timing control device 1 according to the present embodiment. Figs
2 to 4 are cross sectional views illustrating respective states taken along line II-II
in Fig. 1. The valve opening and closing timing control device 1 is mounted on a vehicle
including an engine as an internal combustion engine as a drive source and on a hybrid
vehicle including a drive source including the engine and an electric motor.
[0020] The valve opening and closing timing control device 1 includes an outer rotor 12
serving as a driving-side rotary member and an inner rotor 2 serving as a driven-side
rotary member. The outer rotor 12 rotates synchronously relative to a crankshaft 110
of an internal combustion engine E. The inner rotor 12 is relatively rotatable and
is coaxially positioned relative to the outer rotor 12 while rotating integrally with
a camshaft 101 of the internal combustion engine E. According to the present embodiment,
the valve opening and closing timing control device 1 controls an opening and closing
timing of an intake valve 115 by setting a relative rotational phase (a relative rotational
angle) of the outer rotor 12 and the inner rotor 2 about an axis X.
[0021] The inner rotor 2 is mounted integrally on a distal end portion of the camshaft 101.
Specifically, the inner rotor 2 is fitted in and fixed to the distal end portion of
the camshaft 10 with a fastening bolt 20.
[0022] The valve opening and closing timing control device 1 includes a front plate 11,
the outer rotor 12 and a rear plate 13. The front plate 11 is provided opposite to
a side where the camshaft 101 is connected. The rear plate 13 is integrally formed
with a timing sprocket 15 and is provided at the side where the camshaft 101 is connected.
The inner rotor 2 is covered by the outer rotor 2. The outer rotor 12 is sandwiched
by the front plate 11 and the rear plate 13 from opposing ends in an axial direction.
In this state, the front plate 11, the outer rotor 12 and the rear plate 13 are fitted
in and fixed to one another with the aforementioned fastening bolt 20.
[0023] When the crankshaft 110 is rotationally driven, a rotational driving force is transmitted
to the timing sprocket 15 via a power transmission member 102. The outer rotor 12
is rotationally driven in a rotational direction S shown in Fig. 2. The inner rotor
2 is rotationally driven in the rotational direction S in accordance with the rotational
drive of the outer rotor 12 to rotate the camshaft 101. A cam 116 being provided at
the camshaft 101 opens a valve by pressing down the intake valve 115 of the internal
combustion engine E.
[0024] As shown in Fig. 2, the outer rotor 12 is formed with plural protrusions 14 protruding
inwardly in a radial direction so as to be separated from one another along the rotational
direction S. A fluid pressure chamber 4 is formed by the outer rotor 12 and the inner
rotor 2. The protrusion 4 serves as a shoe relative to an outer peripheral surface
2a of the inner rotor 2. According to the present embodiment, an example in which
four of the fluid pressure chambers 4 are formed is explained, however, is not intended
to limit the scope of the invention.
[0025] A portion of the outer peripheral surface 2a, the portion facing the fluid pressure
chamber 4, is formed with a vane groove 21 of which a depth direction corresponds
to the radial direction of the inner rotor 2. A portion of a vane 22 is inserted into
the vane groove 21 and is standingly positioned outwardly in the radial direction.
Thus, the vane 22 is positioned within the fluid pressure chamber 4.
[0026] The fluid pressure chamber 4 is divided into an advance chamber 41 and a retard chamber
42 with the vane 22. The advance chamber 41 and the retard chamber 42 allow an inflow
and an outflow of an oil along the rotational direction S. In a case where the oil
is supplied to the retard chamber 42, the relative rotational phase of the inner rotor
2 relative to the outer rotor 12 moves (is displaced) in the retarded direction of
the relative rotational direction. The retarded direction corresponds to a direction
in which a volume of the retard chamber 42 increases by the inflow of the oil, the
direction that is shown with a reference numeral S2 in Fig. 2. In a case where the
oil is supplied to the advance chamber 41, the relative rotational phase moves (is
displaced) in the advance direction of the relative rotational direction. The advance
direction corresponds to a direction in which the vane 22 relatively rotationally
moves relative to the outer rotor 12 and corresponds to a direction in which a volume
of the advance chamber 41 increases by the inflow of the oil, the direction shown
with a reference numeral S1 in Fig. 2. A spring 23 is positioned between the vane
groove 21 and the vane 22, and biases the vane 22 outwardly in the radial direction.
Accordingly, the oil is prevented from leaking at a position between the advance chamber
41 and the retard chamber 42. The vane 22 selectively moves the relative rotational
phase between the retarded direction and the advance direction.
[0027] As shown in Figs. 1 and 2, an advance passage 43 is formed at the inner rotor 2 and
at the camshaft 101 so as to be communicated with each of the advance chambers 41.
A retard passage 44 is formed at the inner rotor 2 and at the camshaft 101 so as to
be communicated with each of the retard chambers 42. The advance passage 43 and the
retard passage 44 are connected to respective predetermined ports of a first control
valve 174.
[0028] Because the first control valve 174 is controlled, the oil is maintained to be supplied,
to be discharged, or to be supplied and discharged relative to the advance chamber
41 and the retard chamber 42, and the fluid pressure of the oil is applied to the
vane 22. As such, the relative rotational phase is displaced either in the advance
direction S1 or in the retarded direction S2. Alternatively, the relative rotational
phase is maintained at a desired phase.
[0029] In addition, as shown in Fig. 1, a torsion spring 3 is provided to be extended from
the inner rotor 2 to the front plate 11. The torsion spring 3 biases the inner rotor
2 to a retard side in order to resist an averaged displacing force in the retarded
direction S2 based on a torque variation of the camshaft 101. Thus, the relative rotational
phase can be displaced in the advance direction S1 smoothly and promptly.
[0030] In such a configuration, the inner rotor 2 is smoothly and relatively rotationally
movable relative to the outer rotor 12 about the axis X within a predetermined range.
The predetermined range in which the outer rotor 12 and the inner rotor 2 are relatively
rotationally movable, that is, a phase difference between a most advance phase and
a most retard phase, corresponds to a displaceable range of the vane 22 within the
fluid pressure chamber 4. The most retard phase corresponds to a phase where the volume
of the retard chamber 42 comes to be at a maximum. The most advance phase corresponds
to a phase where the volume of the advance chamber 41 comes to be at a maximum.
[0031] In a state where the fluid pressure level of the oil is not stable immediately after
the start-up of the internal combustion engine E, an intermediate lock mechanism 6
holds the outer rotor 12 and the inner rotor 2 at respective predetermined relative
positions. Accordingly, the relative rotational phase of the outer rotor 12 and the
inner rotor 2 is locked at the intermediate locked phase that is positioned between
the most retard phase and the most advance phase. As such, because the relative rotational
phase is held at the intermediate locked phase, the rotational phase of the camshaft
101 relative to the rotational phase of the crankshaft 110 is appropriately maintained.
Thus, the stable rotation of the internal combustion engine E is realized. According
to the present embodiment, the intermediate locked phase corresponds to a phase in
which the respective opening timings of the intake valve 115 and of the exhaust valve
are partially duplicated (overlapped) with each other, or corresponds to a phase in
which the closing timing of the exhaust valve and the opening timing of the intake
valve 115 are substantially the same (zero lap). As a result, if the phase is such
that the respective opening timings of the intake valve 115 and of the exhaust valve
are partially duplicated with each other, the carbon hydride (HC) is reduced at the
start-up of the internal combustion engine E. Accordingly, the low-emission internal
combustion engine E is available. In addition, if the phase is such that the closing
timing of the exhaust valve and the opening timing of the intake valve 115 are substantially
the same, the combustion engine E that has a great start-up performance at a cold
area and that has a great idling stability is available.
[0032] According to the present embodiment, as shown in Figs. 1 and 2, the intermediate
lock mechanism 6 includes an intermediate lock passage 61, two of intermediate lock
grooves 62, a housing portion 63, two plate-shaped intermediate lock members 64, and
a spring 65. The intermediate lock groove 62 corresponds to a recess of the present
invention, and the intermediate lock member 64 corresponds to a lock member of the
present invention.
[0033] The intermediate lock passage 61 is formed at the inner rotor 2 and at the camshaft
101, and connects the intermediate lock groove 62 to a second control valve 175. Because
the second control valve 175 is controlled, the supply/discharge of the oil to/from
the intermediate lock groove 62 can be switched independently. The intermediate lock
groove 62 is formed to be extended on the outer peripheral surface 2a of the inner
rotor 2 in a circumferential direction and has a predetermined width in the relative
rotational direction. The housing portion 63 is formed at two positions of the outer
rotor 12. Two of the intermediate lock members 64 are positioned at the respective
housing portions 63, and are able to be in and out of the housing portions 63 in the
radial direction. Thus, according to the present embodiment, the intermediate lock
member 64 is formed at the outer rotor 12 and is movable relative to the inner rotor
2. The spring 65 is positioned at the housing portion 63 and biases each of the intermediate
lock members 64 inwardly in the radial direction, that is, biases each of the intermediate
lock members 64 to a side where the intermediate lock groove 62 is provided.
[0034] In a case where the oil is discharged from the intermediate lock groove 62, each
of the two of the intermediate lock members 64 protrudes to be fitted into each of
the intermediate lock grooves 62. Accordingly, each of the intermediate lock members
64 is retained simultaneously at a predetermined position of each of the intermediate
lock grooves 62. As a result, as shown in Fig. 2, the relative rotational phase of
the inner rotor 2 relative to the outer rotor 12 is locked at the aforementioned intermediate
locked phase. In a case where the second control valve 175 is controlled to supply
the oil to the intermediate lock groove 62, as shown in Fig. 3, both of the intermediate
lock members 64 are retracted from the respective intermediate lock grooves 62 to
the respective housing portions 63. Thus, because the relative rotational phase is
unlocked, the inner rotor 2 comes to be relatively rotationally movable. Hereinafter,
a state where the intermediate lock mechanism 6 locks the relative rotational phase
at the intermediate phase is referred to as a lock state. In addition, a state where
the lock state is released is referred to as an unlock state. The intermediate lock
mechanism 6 is switchable between the lock state and the unlock state.
[0035] Meanwhile, for example, a pin shape can be appropriately adapted as the shape of
the intermediate lock member 64 other than the plate shape that is shown in the present
embodiment.
[0036] According to the present embodiment, each of the two of the intermediate lock grooves
62 has a ratchet structure so that the groove depth comes to be gradually deeper along
the retarded direction S2 of the inner rotor 2. Accordingly, the intermediate lock
member 64 is gradually restricted and comes to be easily entered into the intermediate
lock groove 62. Meanwhile, the intermediate lock passage 61 is divided into two on
the way of the inner rotor 2 and is connected to each of the intermediate lock grooves
62.
[0037] The present valve opening and closing timing control device 1 is provided with a
most retarded angle lock mechanism 7 in addition to the aforementioned intermediate
lock mechanism 6. The most retarded angle lock mechanism 7 locks the relative rotational
phase to the most retard phase by holding the outer rotor 12 and the inner rotor 2
at the predetermined relative positions at the time of low-speed rotation, for example,
at the time of an idling operation. That is, irrespective of the displacing force
in the retarded direction S2 and in the advance direction S1 based on the torque variation
of the camshaft 101, because the inner rotor 2 does not relatively rotationally move,
the stable idling operation state can be realized. In addition, according to the present
embodiment, the most retard phase corresponds to a phase where the valve is opened
at a later timing than the closing timing of the exhaust valve, the phase in which
the start-up performance of the internal combustion engine E is secured while preventing
a pre-ignition at a warm area of the internal combustion engine E.
[0038] As shown in Fig. 2, the most retarded angle lock mechanism 7 is provided with a most
retarded angle lock passage 71, a most retarded angle lock groove 72, a housing portion
73, a plate-shaped most retarded angle lock member 74, and a spring 75. According
to the present embodiment, the most retarded angle lock passage 71 is used in parallel
with one of the plural advance passages 43. The most retarded angle lock member 74
serves as a same member as the intermediate lock member 64 being provided at one of
the two of the intermediate lock members 64, the one being positioned in the advance
direction S1. Similarly, the housing portion 73 serves as a same member as the housing
portion 63 being provided at one of the two of the housing portions 63, the one being
positioned in the advance direction S1. The spring 75 serves as a same member as the
spring 65 being positioned at the housing portion 63.
[0039] In such a configuration, in a state where the oil is discharged from the most retarded
angle lock groove 72, the most retarded angle lock member 74 protrudes to the most
retarded angle lock groove 72. As shown in Fig. 4, in a case where the most retarded
angle lock member 74 is retained at the most retarded angle lock groove 72, the relative
rotational movement of the inner rotor 2 relative to the outer rotor 12 is locked
and the relative rotational phase is held at the most retard phase. In a case where
the first control valve 174 is controlled to try to displace the relative rotational
phase to the advance side, the oil is supplied to the most retarded angle lock groove
72. Accordingly, the most retarded angle lock member 74 is retracted from the most
retarded angle lock groove 72 to the housing portion 73. That is, the relative rotational
phase is unlocked.
[0040] In a case where the relative rotational phase corresponds to a phase other than the
most retard phase, because the most retarded angle lock member 74 is dislocated from
the most retarded angle lock groove 72, the most retarded angle rock member 74 is
slidingly in contact with the outer peripheral surface 2a of the inner rotor 2. Meanwhile,
regarding to the shape of the most retarded angle lock member 74, the pin shape can
be appropriately adapted other than the plate shape shown in the present embodiment.
[0041] In such a configuration, in a case where the electric power supply to the second
control valve 175 is stopped at the intermediate lock state shown in Fig. 2, the unlock
state is established as shown in Fig. 3. After that, because the oil is continuously
supplied to the intermediate lock groove 62 as long as the electric power supply to
the second control valve 175 is continuously stopped, the intermediate lock member
64 does not enter into the intermediate lock groove 62.
[0042] As shown in Fig. 4, in a case where the relative rotational phase is displaced to
the most retard phase, and in a case where the most retarded angle lock member 74
faces the most retarded angle lock groove 72, the most retarded angle lock member
74 (64) is entered into the most retarded angle lock groove 72 to be established in
the most retarded angle lock state.
[0043] As such, according to the configuration of the present embodiment, the number of
components can be reduced while the configuration is simplified. Thus, a manufacturing
cost can be reduced. In addition, because the intermediate lock member 64 and the
most retarded angle lock member 74 are commonly used with each other, the outer rotor
12 has an additional space in the circumferential direction, and as shown in Fig.
2, four of the fluid pressure chambers 4 can be provided. As a result, because the
force for displacing the relative rotational phase is increased, the prompt phase
displacement can be realized. In addition, the displaceable range of the relative
rotational phase can be increased by increasing the width of the fluid pressure chamber
4 in the circumferential direction.
[0044] Next, the structure of an oil-pressure passage according to the present embodiment
will be explained. As shown in Fig. 1, the oil-pressure passage is provided with a
pump 171, a first control valve 174 and a second control valve 175. The pump 171 is
driven by the internal combustion engine E and supplies the oil. The first control
valve 174 controls the supply of the oil to the fluid pressure chamber 4. The second
control valve 175 controls the supply of the oil to the intermediate lock mechanism
6.
[0045] A phase control portion 180 controls respective operations of the first control valve
174 and of the second control valve 175 in order to control the aforementioned relative
rotational phase. For example, in a case where the intermediate lock mechanism 6 shifts
from the unlock state to the lock state, the phase control portion 180 controls the
supply of the fluid to the retard chamber 42 and the discharge of the fluid from the
advance chamber 41, or the discharge of the fluid from the retard chamber 42 and the
supply of the fluid to the advance angle chamber 41 in order for the intermediate
lock member 64 to reach the intermediate locked phase. An arithmetic processing unit
is used for the phase control portion 180. The phase control portion 180 is configured
by a single control device or by plural control devices.
[0046] According to the present embodiment, the pump 171 serves as a mechanical oil-pressure
pump that is driven by a rotational force transmitted from the crankshaft 110 of the
intermediate combustion engine E. The pump 171 pumps the stored oil stored in an oil
pan 176 from an inlet port and discharges the oil from an outlet port to a downstream.
The outlet port of the pump 171 is communicated with respective predetermined ports
of the first control valve 174 and of the second control valve 175.
[0047] A variable electromagnetic spool valve can be used for the first control valve 174.
The variable electromagnetic spool valve displaces a spool being positioned within
a sleeve so as to be slidable against a spring by the energization from the phase
control portion 180 to a solenoid. The first control valve 174 includes an advance
port, a retard port, a supply port, and a drain port. The advance port is communicated
with the advance passage 43. The retard port is communicated with the retard passage
44. The supply port is communicated with a flow passage of the downstream of the pump
171. The drain port is communicated with the oil pan 176.
[0048] The first control valve 174 is configured by a three-position control valve that
is able to perform three-state controls that are, an advanced angle control, a retarded
angle control, and a hold control. The advanced angle control communicates the advance
port to the supply port and communicates the retard port to the drain port. The retarded
angle control communicates the retard port to the supply port and communicates the
advance port to the drain port. The hold control closes the advance port and the retard
port. Because the advanced angle control is performed, the vane 22 relatively rotationally
moves in the advance direction S1 relative to the outer rotor 12. The relative rotational
phase is displaced to the advance side. Because the retarded angle control is performed,
the vane 22 relatively rotationally moves in the retarded direction S2 relative to
the outer rotor 12. The relative rotational phase is displaced to the retarded angle.
Because the hold control is performed, the vane 22 does not relatively rotationally
move. The relative rotational phase can be held at a desired phase.
[0049] In a case where the advanced angle control is performed, the oil is supplied to the
advance passage 43 and to the most retarded angle lock passage 71. In the most retarded
angle lock state, the most retarded angle lock passage 71 is closed by the most retarded
angle lock member 74. In the most retarded angle unlock state in which the most retarded
angle lock member 74 is retracted from the most retarded angle lock groove 72 by the
advanced angle control, the oil is supplied to the advance chamber 41 via the advance
passage 43. The inner rotor 2 relatively rotationally moves to the advanced angle.
[0050] The phase control portion 180 controls the first control valve 174 to control the
supply or the discharge of the oil relative to the advance chamber 41 and the most
retarded angle lock passage 71, or the retard chamber 42. Accordingly, the first control
valve 174 performs a switching control of the intermediate lock mechanism 6 between
the lock state and the unlock state, and performs the control of the relative rotational
phase of the inner rotor 2 relative to the outer rotor 12. According to the present
embodiment, when the first control valve 174 is energized, the retarded angle control
comes to be available. When the energization of the first control valve 174 is stopped,
the advanced angle control comes to be available. In addition, the first control valve
174 sets the opening by the adjustment of the duty ratio of the electric power being
supplied to an electromagnetic solenoid. Accordingly, the fine adjustment of the supply/discharge
amount of the oil is available.
[0051] Similarly to the first control valve 174, a variable electromagnetic spool valve
is used for the second control valve 175. The second control valve 175 includes a
restriction port, a supply port and a drain port. The restriction port is communicated
with the intermediate lock passage 61. The supply port is communicated with the flow
passage of the downstream of the pump 171. The drain port is communicated with the
oil pan 176. The second control valve 175 is configured as a two-position control
valve being able to control two-state controls that are a release control and a restriction
control. The release control communicates the restriction port to the supply port.
The restriction control communicates the restriction port to the drain port. The phase
control portion 180 controls the second control valve 175 to control the supply/discharge
of the oil to/from the intermediate lock groove 62 of the intermediate lock mechanism
6. As such, the second control valve 175 performs the switching control of the intermediate
lock mechanism 6 between a restricted state or a released state.
[0052] The second control valve 175 can switch between the supply of the oil to the intermediate
lock groove 62 and the discharge of the oil from the intermediate lock groove 62.
According to the present embodiment, the second control valve 175 is configured such
that when the second control valve 175 is energized, the oil can be discharged from
the intermediate lock groove 62, and the energization of the second control valve
175 is stopped, the oil can be supplied to the intermediate lock groove 62.
[0053] Here, a crank angle sensor detecting a rotational angle of the crankshaft 11 is provided
in the vicinity of the crankshaft 110 of the internal combustion engine E. A camshaft
angle sensor detecting a rotational angle of the camshaft 101 is provided in the vicinity
of the camshaft 101. The phase control portion 180 detects the relative rotational
phase from detection results of the crank angle sensor and of the camshaft angle sensor
and determines which phase the relative rotational phase is positioned. In addition,
for example, the on/off information of an ignition key is transmitted to the phase
control portion 180. The control information of an optimum relative rotational phase
in accordance with an operation state of the internal combustion engine E is memorized
within a memory of the phase control portion 180. The phase control portion 180 controls
the relative rotational phase in accordance with the operation state of the internal
combustion engine E.
[0054] The phase control portion 180 according to the present embodiment performs one of
a control of the supply of the fluid to the retard chamber 42 and the discharge of
the fluid from the advance chamber 41, and a control of the discharge of the fluid
from the retard chamber 42 and the supply of the fluid to the advance chamber 41 by
reducing the travelling speed of the relative rotational phase from a reference phase
to the intermediate locked phase to be slower than the travelling speed of the relative
rotational phase to the reference phase that is provided between a present phase and
the intermediate locked phase. According to the present embodiment, regarding the
present phase, as mentioned above, the phase control portion 180 detects the relative
rotational phase from the detection results of the crank angle sensor and of the camshaft
angle sensor, and determines which phase the relative rotational phase is positioned.
The reference phase is provided between the present phase and the intermediate locked
phase. The reference phase can be provided to be changeable to an intermediate position
each time between the present phase and the intermediate locked phase. Alternatively,
the reference phase can be pre-provided in the vicinity of the intermediate locked
phase.
[0055] Figs. 5 and 6 schematically illustrate the reference phase and the intermediate locked
phase. Fig. 5 shows an example of a case where two of the intermediate lock members
64 move to the intermediate locked phase from a state where the intermediate lock
members 64 are not positioned within the intermediate lock grooves 62, respectively,
by the rotation of the inner rotor 2 in the advance direction S1. Fig. 6 shows an
example of a case where two of the intermediate lock members 64 move to the intermediate
locked phase from a state where the intermediate lock members 64 are not positioned
within the intermediate lock grooves 62, respectively, by the rotation of the inner
rotor 2 in the retarded direction S2. In Figs. 5 and 6, in a case where a position
having a reference numeral A corresponds to the intermediate locked phase and in a
case where a position having a reference numeral O corresponds to the present phase,
a reference phase P is provided therebetween. Meanwhile, the reference phase P is
provided within the intermediate lock groove 62 in Fig. 5. Alternatively, the reference
phase P can be provided at an out of the intermediate lock groove 62. Furthermore,
the reference phase P is provided at the out of the intermediate lock groove 62 in
Fig. 6. Alternatively, the reference phase P can be provided within the intermediate
lock groove 62.
[0056] In such a case, the phase control portion 180 performs one of the control of the
supply of the fluid to the retard chamber 42 and the discharge of the fluid from the
advance chamber 41, and the control of the discharge of the fluid from the retard
chamber 42 and the supply of the fluid to the advance chamber 41 so as to reduce the
traveling speed of the relative rotational phase by a predetermined amount of change
from a position O of the present phase to a position A of the intermediate locked
phase via a position P of the reference phase. The reduction of the speed by the predetermined
amount of change indicates that the travelling speed is reduced by a predetermined
negative acceleration and indicates that the travelling speed is reduced gradually
as shown in Fig. 7. Accordingly, the relative rotational phase can be promptly and
securely moved from the present phase to the intermediate locked phase.
[0057] Meanwhile, a change of the travelling speed shown in Fig. 7 corresponds to an example.
For example, as shown in Fig. 8, the relative rotational phase moves from the position
O of the present phase to the position P of the reference phase based on a predetermined
first travelling speed. The relative rotational phase can move from the position P
of the reference phase to the position A of the intermediate locked phase based on
a second travelling speed that is slower than the first travelling speed. While the
relative rotational phase travels from the position O of the present phase to the
position A of the intermediate locked phase, the travelling speed of the relative
rotational phase can be naturally changed by equal to or more than three steps.
[0058] According to the present embodiment, a determination portion 181 determines whether
the intermediate lock member 64 reaches the reference phase when the phase control
portion 180 controls the intermediate lock member 64 to travel to a side where the
reference phase is positioned after controlling the supply and discharge. The control
of the supply and discharge by the phase control portion 180 serves as a control performing
one of the control of the supply of the fluid to the retard chamber 42 and the discharge
of the fluid from the advance chamber 41, and the control of the discharge of the
fluid from the retard chamber 42 and the supply of the fluid to the advance chamber
41 so that the intermediate lock member 64 comes to be positioned at the intermediate
locked phase.
[0059] Controlling the intermediate lock member 64 to travel to a side where the reference
phase is positioned (a side of a position of the present phase in a case where the
intermediate lock member 64 travels to the intermediate locked phase) will hereunder
be explained as a determination control. After the determination control, in a case
where the determination portion 181 determines that the intermediate lock member 64
reaches the position P of the reference phase, the result is transmitted to the phase
control portion 180. In such a case, the phase control portion 180 recognizes that
the relative rotational phase of the inner rotor 2 relative to the outer rotor 12
does not correspond to the intermediate locked phase. The phase control portion 180
controls the first control valve 174 to travel to the intermediate locked phase.
[0060] Meanwhile, after the determination control, in a case where the determination portion
181 determines that the intermediate lock member 64 does not reach the position P
of the reference phase, the result is transmitted to the phase control portion 180.
In such a case, the phase control portion 180 recognizes that the relative rotational
phase of the inner rotor 2 relative to the outer rotor 12 corresponds to the intermediate
locked phase. The phase control portion 180 stops the control of the first control
valve 174.
[0061] According to the present embodiment, in a case where the determination portion 181
determines that the intermediate lock member 64 is not provided at the position P
of the reference phase after the control of the supply and discharge by the first
control valve 174, the phase control portion 180 alternately supplies the fluid to
the retard chamber 42 and to the advance chamber 41. The case where the determination
portion 181 determines that the intermediate lock member 64 is not provided at the
position P of the reference phase after the control of the supply and discharge by
the first control valve 174 corresponds to a case where the intermediate lock member
64 is positioned at the intermediate locked phase. In such a case, because the relative
rotation of the inner rotor 2 and the outer rotor 12 is restricted, the vane 22 swings
in the advance direction S1 and in the retarded direction S2 in a state where the
relative rotation is restricted by the supply of the fluid alternately to the retard
chamber 42 and to the advance chamber 41 by the phase control portion 180. As such,
because the intermediate lock member 64 does not reach the reference phase, it can
be determined that the intermediate lock member 64 is securely fitted in the intermediate
lock groove 62. Accordingly, according to this configuration, the fitted-in state
of the intermediate lock member 64 can be confirmed. Because the respective oil pressure
levels of the retard chamber 42 and of the advance chamber 41 increase and decrease,
the respective oil pressure levels of passages being connected to the retard chamber
42 and to the advance chamber 41 increase and decrease in accordance with the oil
pressure levels of the retard chamber 42 and of the advance chamber 41. Accordingly,
extraneous materials within the passages can be circulated and removed (cleaned).
[Another embodiment]
[0062] According to the aforementioned embodiment, each of two of the intermediate lock
grooves 62 has the ratchet structure so that the groove depth comes to be gradually
deeper along the retarded direction S2 of the inner rotor 2. However, the applicability
of this invention is not limited to this. The intermediate lock groove 62 can be naturally
configured to have a constant groove depth.
[0063] In the aforementioned embodiment, two of the intermediate lock grooves 62 and two
of the intermediate lock members 64 are provided. However, the applicability of this
invention is not limited to this. For example, the single intermediate lock groove
62 and the single intermediate lock member 64 are provided and the intermediate lock
groove 62 has the ratchet structure so that the groove depth comes to be gradually
deeper along the retarded direction S2 of the inner rotor 2. In such a case, it is
favorable that the length of the intermediate lock groove 62 in the circumferential
direction, the length of a position having a deeper groove, is set at a degree where
the outer rotor 12 and the inner rotor 2 do not relatively rotate with each other
in a case where the intermediate lock member 64 is fitted into the deeper groove.
[0064] Alternatively, the intermediate lock groove 62 can be configured to have a constant
groove depth. In such a case, it is favorable that the length of the intermediate
lock groove 62 in the circumferential direction is set at a degree where the outer
rotor 12 and the inner rotor 2 allow relative rotation with each other in a case where
the intermediate lock member 64 is fitted into the intermediate lock groove 62.
[0065] In the aforementioned embodiment, the intermediate lock member 64 is explained to
be provided at the outer rotor 12 and the intermediate lock groove 62 is explained
to be provided at the inner rotor 2. However, the applicability of this invention
is not limited to this. The intermediate lock member 64 can be naturally provided
at the inner rotor 2 and the intermediate lock groove 62 can be configured to be naturally
provided at the outer rotor 12.
[0066] In the aforementioned embodiment, in a case where the determination portion 181 determines
that the intermediate lock member 64 is not provided at the position P of the reference
phase after the control of the supply and discharge by the first control valve 174,
the phase control portion 180 is explained to alternately supply the fluid to the
retard chamber 42 and to the advance chamber 41. However, the applicability of this
invention is not limited to this. In a case where the determination portion 181 determines
that the intermediate lock member 64 is not provided at the position P of the reference
phase after the control of the supply and discharge by the first control valve 174,
the phase control portion 180 can be naturally configured so as not to 1 alternately
supply the fluid to the retard chamber 42 and to the advance chamber 4. Furthermore,
the phase control portion 180 can be configured so as to supply the fluid to the retard
chamber 42 and to the advance chamber 41 alternately in a case where the determination
portion 181 performs the determination.
[0067] According to the aforementioned embodiment, an example where the valve opening and
closing timing control device 1 controls the opening and closing timing of the intake
valve 115 is explained. However, the applicability of this invention is not limited
to this. The valve opening/control timing control device 1 can be configured to naturally
control the opening and closing timing of the exhaust valve.
[0068] According to the aforementioned embodiment, the determination portion 181 is explained
to determine whether the intermediate lock member 64 reaches the reference phase when
the intermediate lock member 64 is controlled to move to the reference phase after
the control of the supply and discharge by the phase control portion 180. However,
the applicability of this invention is not limited to this. A position of a determination
phase is provided between the position A of the intermediate locked phase and the
position P of the reference phase. The phase control portion 180 performs one of the
control of the supply of the fluid to the retard chamber 42 and the discharge of the
fluid from the advance chamber 41, and the control of the discharge of the fluid from
the retard chamber 42 and the supply of the fluid to the advance chamber 41. After
that, the determination portion 181 determines whether the intermediate lock member
64 reaches the position of the determination phase when the phase control portion
180 controls the intermediate lock member 64 to move to the determination phase side.
In such a case, because a position between the intermediate locked phase and the position
for determination (the position of the determination phase) can be shallow, the determination
portion 181 can determine whether the intermediate lock member 64 reaches the intermediate
locked phase more securely.
[0069] According to the aforementioned embodiment, the phase control portion 180 is explained
to perform one of the control of the supply of the fluid to the retard chamber 42
and the discharge of the fluid from the advance chamber 41, and the control of the
discharge of the fluid from the retard chamber 42 and the supply of the fluid to the
advance chamber 41 so that the travelling speed of the relative rotational phase from
the present phase to the intermediate locked phase is reduced by the predetermined
amount of change. However, the applicability of this invention is not limited to this.
For example, the phase control portion 180 performs one of the control of the supply
of the fluid to the retard chamber 42 and the discharge of the fluid from the advance
chamber 41, and the control of the discharge of the fluid from the retard chamber
42 and the supply of the fluid to the advance chamber 41 based on a map that is defined
by a relationship between the travelling speed of the relative rotational phase from
the present phase to the intermediate locked phase and the quantity of state showing
a state of the fluid that is flowed to the retard chamber 42 and to the advance chamber
41. The quantity of state showing the state of the fluid corresponds to a temperature
level and a pressure level of the fluid, for example. The map that defines the traveling
speed with the relationship of the temperature level and the pressure level of the
fluid is pre-memorized, and the phase control portion 180 can be configured to control
the oil pressure levels of the retard chamber 42 and of the advance chamber 41 based
on the map. In such a case, because the phase control portion 180 controls the travelling
speed from the reference phase to the intermediate locked phase to be slower than
the travelling speed from the present phase to the reference phase, the relative rotational
phase can be promptly travelled to the intermediate locked phase.
INDUSTRIAL AVAILABILITY
[0070] The present invention is applicable to a valve opening and closing timing control
device that controls the relative rotational phase of a driven-side rotary member
rotating integrally with a camshaft of an internal combustion engine relative to a
driving-side rotary member rotating synchronously with a crankshaft of the internal
combustion engine.
EXPLANATION OF REFERENCE NUMERALS
[0071]
- 1
- valve opening and closing timing control device
- 2
- inner rotor (driven-side rotary member)
- 4
- fluid pressure chamber
- 6
- intermediate lock mechanism
- 12
- outer rotor (driving-side rotary member)
- 22
- vane
- 41
- advance chamber
- 42
- retard chamber
- 62
- intermediate lock groove (recess)
- 64
- intermediate lock member (lock member)
- 101
- camshaft
- 110
- crankshaft
- 180
- phase control portion
- E
- internal combustion engine
- S1
- advance direction
- S2
- retarded direction