JP3086118B2 - Valve timing control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve timing control device, and more particularly, to a valve timing control device for varying the opening / closing timing of a valve during operation of an engine.

[0002]

2. Description of the Related Art Conventionally, as an engine provided with a valve timing control device, an engine disclosed in Japanese Patent Application Laid-Open No. 57-212310 has been proposed. In this technique, when the control device operates in response to the load of the engine, one of the pair of solenoids is energized. When one of the solenoids is energized, the spool valve moves in the direction A.
Therefore, the hydraulic pressure is supplied to the retard chamber. On the other hand, the oil pressure in the advance chamber is collected in the oil tank. Therefore, the slider slides rightward (direction A). This sliding of the slider retards the valve timing.

When the other solenoid is energized, the spool valve moves in the direction B. Therefore, the hydraulic pressure is supplied to the advance chamber. On the other hand, the oil pressure in the retard chamber is collected in the oil tank. Therefore, the slider slides leftward (direction B). The valve timing is advanced by the sliding of this slider.

Accordingly, the valve timing is controlled so that the intake air amount is increased when the engine is fully loaded, and the intake air amount is decreased when the engine is partially loaded.

[0005]

However, according to the above-mentioned prior art , when the valve is in the most retarded state or the most advanced state during the valve timing control, one of the chambers does not operate.
Lubricant will be washed away, even if an attempt is then advanced or retarded, it is impossible to move <br/> moving the Ringugi A until filling the lubricating oil into the chamber, the responsiveness of the valve timing control apparatus There was a problem of getting worse.

In particular, when the ring gear is located at the end in the direction of the thrust force generated by the rotation of the helical spline of the ring gear and thereafter starts moving against the thrust force, the lubricating oil is supplied to the chamber. After the ring gear is filled, the ring gear cannot move until a hydraulic pressure sufficient to overcome the thrust force is generated, and the responsiveness is further deteriorated.

The present invention has been made in view of the above circumstances, and has as its object to be able to hold lubricating oil in a hydraulic chamber even when supply of lubricating oil to one hydraulic chamber is unnecessary for control. In addition, an object of the present invention is to provide a valve timing control device that improves responsiveness of the valve timing control device by prohibiting unnecessary valve timing control under predetermined operating conditions.

[0008]

In order to achieve the above object, according to the first aspect of the present invention , a spline is provided on the inner and outer peripheral surfaces.
Formed, at least one of which is a helical spline
Arrange a ring gear between pulley and camshaft
The pulley and the camshaft are linked by the ring gear.
As well as advance into the pulley by the ring gear.
Side hydraulic chamber and the retard side hydraulic chamber
The oil pressure of the lubricating oil is adjusted according to the opening to advance the hydraulic pressure on the advance side.
Control valve to supply to the hydraulic chamber and the retard hydraulic chamber
Engine having an operating state detected by the operating state detecting means
Oil control valve opening based on operating conditions
The lubricating oil is controlled by the timing control
Lubricating oil supplied to the pressure chamber or the retard side hydraulic chamber
Ring gear in the axial direction of the camshaft based on the hydraulic pressure
To change the relative position between the pulley and camshaft.
Valve timing to control valve timing
The actual valve type of the valve.
Actual valve timing detecting means for detecting the
Target valve timing and front according to engine operating conditions
The deviation from the actual valve timing is less than the specified value
Deviation determination means for determining that
The position of the ring gear corresponding to the
At the end of the corner-side hydraulic chamber, and
Is determined to be less than or equal to a predetermined value.
The ring gear in the hydraulic chamber on the side where the ring gear is located.
Hydraulic pressure that does not move the camshaft in the axial direction of the camshaft.
Oil control valve so that lubricating oil is supplied.
Lubricating oil pressure control means for controlling the opening of the valve
are doing.

The invention according to a second aspect is characterized in that the inner and outer peripheral surfaces have
Are formed, at least one of which is a helical spur
Ring gear between the pulley and camshaft
And a pulley and a camshaft are arranged by the ring gear.
And the ring gear
Hydraulic pressure generating means forming an advance side hydraulic chamber and a retard side hydraulic chamber
The oil pressure of the lubricating oil is adjusted according to the opening to advance the
Oil control to supply to hydraulic chamber and retard side hydraulic chamber
An engine that has a valve and is detected by the operating state detecting means.
Oil control valve based on operating conditions
Advance the lubricating oil by controlling the opening by timing control means
To the hydraulic chamber on the side or the retard side, and
Ring gear is camshaft based on lubricating oil pressure
To change the relative position between the pulley and camshaft.
To control the valve timing of the valve
An actual valve of said valve
Actual valve timing detection means for detecting timing;
Target valve timing according to the operating state of the engine
And the deviation from the actual valve timing is less than a predetermined value
Deviation determining means for determining that there is
The position of the ring gear corresponding to the
Thrust generated by the rotation of the helical spline
Detects the specific operation state at the end of the ring gear stroke in the direction of
Specific operating state detecting means, and the specific operating state detecting means
Is detected as being in a specific operation state, and the deviation
The determination means determines that the deviation is equal to or less than a predetermined value.
Under the condition that the pressure difference between the two hydraulic chambers
The force generated in the gear may be smaller than the thrust force.
So that it acts in the direction against the thrust force
Control the opening of the oil control valve to
Lubricating oil pressure control means for supplying lubricating oil to the hydraulic chamber
Like that.

[0010]

[0011]

[0012]

According to the first aspect of the present invention, a tire is detected based on the operating state of the engine detected by the operating state detecting means.
Control means controls the opening of the oil control valve.
Controlling the lubricating oil pressure from the oil pressure generating means
Lubricating oil is supplied to the advance hydraulic chamber or the retard hydraulic chamber. So
The ring gear closes the advance hydraulic chamber or the retard hydraulic chamber.
When located near the end, the lubrication hydraulic control means
Lubricating oil to the hydraulic chamber on the side where
To prevent air from entering the hydraulic chamber.

Therefore, control responsiveness can be ensured while maintaining the pulley and the camshaft at an appropriate relative position .

[0014]

According to the second aspect of the present invention, when the engine is in a specific operation state and the deviation between the target valve timing and the actual valve timing is equal to or less than a predetermined value, the hydraulic pressure of each hydraulic chamber is adjusted. Oil control valve so that the force generated by the pressure difference acts in the direction against the thrust force and is equal to or less than the thrust force generated in the ring gear.
The hydraulic pressures of both hydraulic chambers are controlled through the opening degree control . Therefore, in the specific operating state of the engine, after the ring gear moves to a position near the target valve timing,
Due to the pressure difference between the oil pressures on both sides of the ring gear, it gradually moves in the direction of the thrust force. Therefore, since the hydraulic pressure is maintained after moving to the valve timing according to the specific operation state,
The response speed to the valve timing according to the specific operation state is also improved, and the response speed to a subsequent change in the operation state is also improved.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a valve timing control device according to the present invention will be described below with reference to FIGS.

As shown in FIG. 1, a camshaft 1 is provided for driving an intake valve or an exhaust valve of an engine (not shown), and a journal 2 is provided between a bearing 4 of a cylinder head 3 and a bearing cap 5. Supported rotatably between them. The journal 2 is formed with two journal grooves 6 and 7 extending along the outer periphery. A first head oil passage 8 and a second head oil passage 9 for supplying lubricating oil to each of the journal grooves 6 and 7 and the journal 2 are formed in the cylinder head 3.

An oil pump 4 as a hydraulic pressure generating means
1, an oil pan 42, an oil filter 43, a valve operating mechanism, a crank mechanism and the like constitute an engine lubrication system. That is, one ends of the first head oil passage 8 and the second head oil passage 9 are connected to an electromagnetically controlled oil control valve (hereinafter simply referred to as OCV) 44,
V44 is connected to an oil pan 42 via an oil filter 43, an oil pump 41, and an oil strainer 45. The oil pump 41 is drivingly connected to the engine GN, and pumps up and discharges lubricating oil in conjunction with the operation of the engine GN.

When the oil pump 41 is driven, lubricating oil is sucked up from the oil pan 42 via the oil strainer 45. After the lubricating oil passes through the oil filter 43, the OCV 44 is supplied to the head oil passages 8, 9 with a predetermined pressure by the operation of the OCV 44, and is supplied to the journal grooves 6, 7 and the journal 2. . Here, the supply amount of the lubricating oil to the head oil passages 8 and 9 can be arbitrarily adjusted by the OCV 44. The detailed configuration of the OCV 44 will be described later.

Next, a mechanism for adjusting the valve timing will be described. A timing pulley housing 10 forming a pulley is provided at the tip of the camshaft 1. This timing pulley 10 is a pulley body 1
1 and a cover 12 attached so as to cover one side surface of the pulley body 11 and the tip of the camshaft 1. The pulley body 11 has a substantially disk shape, a plurality of external teeth 13 are formed on the outer periphery thereof, and a boss 14 is formed in the center. The pulley body 11 is mounted by its boss 14 so as to be relatively rotatable with respect to the camshaft 1. or,
A timing belt 15 is attached to the external teeth 13,
The timing pulley housing 10 is
Is drivingly connected to a crankshaft (not shown) of the internal combustion engine.

On the other hand, the cover 12 has a cylindrical shape with a bottom, and the cover 12 has a small diameter portion 13a and a large diameter portion 13b. A flange 16 is formed on the outer periphery of the cover 12, and a communication hole 17 is formed in the center of the bottom. A plurality of internal teeth 12a are formed on the inner periphery of the small diameter portion 13a. The cover 12 is fixed to one side surface of the pulley main body 11 by a plurality of bolts 18 and pins 19 at its flange 16. Further, a lid 20 is detachably attached to the communication hole 17. A space surrounded by the pulley main body 11 and the cover 12 is a housing space 21 formed inside the timing pulley housing 10.

In the housing space 21, an inner cap 22 is provided at the tip of the camshaft 1 with a hollow bolt 23.
And is prevented from rotating by the pin 24. The inner cap 22 and the pulley body 1
1 is relatively rotatable. Also, inner cap 2
A plurality of external teeth 22b are formed on the outer periphery of the peripheral wall 22a formed on the outer peripheral surface of the second.

A ring gear 25 is disposed between the timing pulley housing 10 and the camshaft 1, and the ring gear 25 allows the timing pulley housing 10
And the camshaft 1 are connected. That is, the ring gear 25 has an annular shape, and the timing pulley housing 10
Are accommodated in the accommodation space 21 so as to be able to reciprocate along the axial direction of the camshaft 1. The ring gear 25 has a ring portion 25a and a flange 25b which projects outward at one end of the ring portion 25a and is in sliding contact with the inner peripheral surface of the large diameter portion 13b.
And the inner and outer circumferences of the ring portion 25a have teeth 25
c and 25d are formed respectively. Both the plurality of teeth 25c and 25d provided on the inner and outer circumferences of the ring gear 25 are helical teeth, and are rotatable relative to the camshaft 1 by moving in the axial direction.

The teeth 25d on the inner periphery of the ring gear 25
Are attached to the external teeth 22b of the inner cap 22 and the ring gear 25
Are meshed with the internal teeth 12a of the cover 12, respectively. Accordingly, when the timing pulley housing 10 is rotationally driven, the timing pulley housing 10 and the inner cap 22 connected by the ring gear 25 are integrally rotated, and the camshaft 1 is integrally formed with the timing pulley housing 10. It is driven to rotate.

In the accommodation space 21, the ring gear 2
An advance-side hydraulic chamber 26 is formed between the ring portion 25 a of the fifth and the bottom of the cover 12. Similarly, accommodation space 21
, A retard side hydraulic chamber 27 is formed between the flange 25 b of the ring gear 25 and the pulley main body 11.

Here, a first shaft passage 28 extending along the center of the camshaft 1 is formed in the camshaft 1 in order to supply oil pressure by lubricating oil to the advance hydraulic pressure chamber 26. The distal end side of the shaft passage 28 communicates with the advance hydraulic chamber 26 through the center hole 23 a of the hollow bolt 23. The proximal end of the shaft oil passage 28 communicates with the journal groove 6 through an oil hole 29 extending in the radial direction of the camshaft 1.

On the other hand, a second shaft oil passage 30 extending in parallel with the first shaft oil passage 28 is formed in the camshaft 1 in order to supply oil pressure by lubricating oil to the retard hydraulic oil chamber 27. One circumferential groove 31 extending along the outer periphery of the camshaft 1 is formed near the tip of the camshaft 1. A part of the circumferential groove 31 is used as the second shaft oil passage 30.
Is communicated to. Further, an oil hole 32 is formed in a part of the boss 14 of the pulley body 11 so as to communicate the circumferential groove 31 with the retard hydraulic chamber 27. The proximal end of the second shaft oil passage 30 communicates with the other journal groove 7.

A seal ring 35 is provided between the outer peripheral surface of the flange 25b of the ring gear 25 and the inner peripheral surface of the large diameter portion 12b. The flange-side hydraulic chamber 26 and the retard-side hydraulic chamber 27 are separated by the flange 25b as separate spaces. Therefore, the inflow and outflow of the lubricating oil to and from the hydraulic chambers 26 and 27 are performed through independent and separate circuits including the above-described oil passages 8, 9, 28, 30, and the like.

In this embodiment, when the pulley body 11, the ring gear 25 and the camshaft 1 are rotated by the driving of the engine GN, the teeth 25c, which are helical splines provided on the inner and outer circumferences of the ring gear 25, 25d
Accordingly, a thrust force that moves in the axial direction of the camshaft 1 is generated in the ring gear 25. The ring gear 25 can move toward the advance hydraulic pressure chamber 26 by the thrust force.

Next, the OCV 44 will be described. The OCV 44 adjusts the amount of lubricating oil supplied to the first head oil passage 8 and the second head oil passage 9, and moves the ring gear 25 or stops the ring gear 25 at an arbitrary position. The OCV 44 has a sleeve 51 and a spool 5
2 and a solenoid 53. The sleeve 51 has a supply port 54, a first discharge port 55, a second discharge port 56, and a common drain port 57. The supply port 54 is connected to the oil pump 41.
Further, the first discharge port 55 is connected to the first head oil passage 8, and the second discharge port 56 is connected to the second head oil passage 9. Further, the common drain port 57 is connected to the drain 47. A spring 62 is disposed on the left side of the spool 52, and the biasing force of the spring 62 urges the spool 52 to always move to the right.

The spool 52 is disposed in the sleeve 51 so as to be slidable in the front-rear direction. Spool 52
Are formed with a predetermined interval on the outer periphery thereof.

On the right side of the OCV 44, a solenoid 53 is provided.
Are connected. Excitation of the solenoid 53 is performed by an electronic control unit (Electronic Control Uniform) serving as a timing control unit, a lubrication oil pressure control unit, and a deviation determination unit, which will be described later.
t: Hereafter, the excitation is controlled by the excitation current from the ECU 71. Spool 52
Reciprocates based on the magnitude of the exciting current from the ECU 71.

The input side of the ECU 71 has an engine GN
A rotation speed sensor 81 as operation state detection means for detecting the number of rotations, an operation state detection means for detecting a cam angle,
A cam angle sensor 82 as a specific operating state detecting means and an actual valve timing detecting means, an operating state detecting means for detecting a crank angle, a crank angle sensor 83 as a specific operating state detecting means and an actual valve timing detecting means,
Throttle sensor 84 as operating state detecting means for detecting the opening of the throttle valve, water temperature sensor 85 as operating state detecting means for detecting the coolant temperature, and air flow meter 86 as operating state detecting means for detecting the amount of intake air, shown. A lever position sensor 87 or the like is connected as operating state detection means for detecting that the automatic shift lever not to be placed is in the parking or neutral position. The ECU 71 determines the operating state of the engine GN based on the detection signals from these sensors 81 to 87.

The output side of the ECU 71 is provided with the OCV4
Four solenoids 53 are connected. And ECU
Reference numeral 71 designates an operating state of the engine GN at that time based on detection signals from the various sensors 81 to 87. Then, a duty signal for calculating a valve opening / closing timing suitable for the operating state of the engine GN at that time is calculated. ECU7
Numeral 1 supplies an exciting current based on the calculated duty signal to the solenoid 53 to excite the solenoid 53. Therefore, based on the magnitude of the exciting current, the spool 5
2 reciprocates, and the amount of connection between the first head oil passage 8 and the supply port 54 and the common drain port 57 is adjusted based on the amount of movement. Similarly, the amount of connection between the second head oil passage 9 and the supply port 54 and the common drain 57 is adjusted based on the amount of movement of the spool 52.

For example, when the solenoid 53 is demagnetized (duty ratio = 0%), the spool 52 moves to the left by the urging force of the spring 62 and stops at the position shown in FIG. Then, the first discharge port 55
Is connected to the common drain port 57, so that the first head oil passage 8 is connected to the drain 47. The amount of connection between the first head oil passage 8 and the drain 47 is maximum (100
%). On the other hand, since the second discharge port 56 is connected to the supply port 54, the second head oil passage 9 is connected to the oil pump 41. This second head oil passage 9
The connection amount between the oil pump 41 and the oil pump 41 is maximum (100%).

Therefore, the lubricating oil from the supply port 54 is supplied to the retard hydraulic chamber 27 via the second head oil passage 9 and the second shaft oil passage 30. Also, the advance side hydraulic chamber 26
The lubricating oil inside the first shaft oil passage 28, the first head oil passage 8, the first discharge port 55 and the common drain port 5
7, and is discharged to the drain 47. Accordingly, the ring gear 25 moves to the advance side hydraulic chamber 26 due to the oil pressure of the lubricating oil supplied into the retard side hydraulic chamber 27. When the ring gear 25 comes into contact with the bottom of the cover 12, the ring gear 2 is located at the end (most retarded side) of the advance side hydraulic chamber 26. Due to the arrangement of the ring gear 25, the relative angle (relative position) between the pulley body 11 and the camshaft 1
Is set to the most retarded side.

When the solenoid 53 is excited by the maximum exciting current (duty ratio = 100%), the spool 52 moves rightward against the urging force of the spring 62 and stops at the position shown in FIG. It has become. Then, since the first discharge port 55 is connected to the supply port 54, the first head oil passage 8 is connected to the oil pump 41. The connection amount between the first head oil passage 8 and the oil pump 41 is maximum (100%). On the other hand, since the second discharge port 56 is connected to the common drain port 47, the second head oil passage 9 is connected to the drain 47. The connection amount between the second head oil passage 9 and the drain 47 is maximum (100%).

Therefore, the lubricating oil from the supply port 54 is supplied to the advance hydraulic chamber 26 via the first head oil passage 8 and the first shaft oil passage 28. Further, the retard side hydraulic chamber 27
The lubricating oil inside the second shaft oil passage 30, the second head oil passage 9, the second discharge port 56 and the common drain port 5
7, and is discharged to the drain 47. Accordingly, the ring gear 25 moves to the retard hydraulic chamber 27 due to the oil pressure of the lubricating oil supplied into the advance hydraulic chamber 26. When the ring gear 25 comes into contact with the pulley main body 11, the ring gear 25 is placed at the terminal end (most advanced side) of the retard side hydraulic chamber 27. Due to the arrangement of the ring gear 25, the relative angle (relative position) between the pulley body 11 and the camshaft 1
Is set to the most advanced side.

Further, in this embodiment, when the solenoid 53 is excited with an exciting current corresponding to a duty ratio of about 28% to 70%, the spool 52 moves in proportion to the magnitude of the exciting current. At this time, as shown in FIG.
Although the connection amount varies depending on the movement amount of the spool 52, the supply port 54 is connected to the first and second discharge ports 55,
56. Similarly, although the amount of connection varies depending on the amount of movement of the spool 52, the common drain port 57 is connected to the first and second discharge ports 55,5.
6 is connected.

At this time, the lubricating oil supplied from the supply port 54 is discharged to the common drain 57, but the lubricating oil can also be supplied to the first and second head oil passages 8 and 9. ing. Accordingly, lubricating oil is supplied to the advance hydraulic chamber 26 and the retard hydraulic chamber 27, and the lubricating oil can simultaneously generate hydraulic pressure in the advance hydraulic chamber 26 and the retard hydraulic chamber 27. It has become.

When the duty ratio is 28% or less, as described above, the spool 52 stops at the position shown in FIG. 1, and when the duty ratio is 70% or more, as described above, the spool 52 It stops at the position shown in FIG.

FIG. 4A shows the amount of movement of the spool 52 moved by the exciting current based on the duty ratio. A change in the amount of movement of the spool 52 changes the amount of connection between the supply port 54 and the first and second discharge ports 55 and 56. When lubricating oil is supplied to the advance hydraulic chamber 26 and the retard hydraulic chamber 27 due to the change in the amount of movement of the spool 52, the change in the hydraulic pressure in the hydraulic chambers 26 and 27 is shown in FIG. .

The advance side hydraulic chamber 26 and the retard side hydraulic chamber 2
FIG. 4C shows a characteristic indicating whether the ring gear 25 moves to the advance side or the retard side at that time due to the change of the oil pressure in the inside 7. When the duty ratio is set to 55% or less, the ring gear 25 moves to the retard side (advance side hydraulic chamber 26 side). This corresponds to the advance side and retard side hydraulic chambers 26, 27.
The hydraulic pressure is applied to each of
7 is higher than the oil pressure in the advance-side hydraulic chamber 26 due to the thrust force of the ring gear 25.
Here, when the duty ratio is between 48% and 55%,
The reason that the ring gear 25 moves to the retard side despite the hydraulic pressure of the advance hydraulic chamber 26 being larger than the hydraulic pressure of the retard hydraulic chamber 27 is that the thrust force generated in the ring gear 25 is large. This is because the pressure difference is larger than the pressure difference between the oil pressure chambers 26 and 27 on both sides.

When the duty ratio is equal to or more than 60%, the ring gear 25 moves to the advance side (the retard side hydraulic chamber 27 side). This corresponds to the advance side and retard side hydraulic chambers 26, 27.
The hydraulic pressure is applied to each of the advance hydraulic chambers 2
Towards the oil pressure in 6 is higher than the hydraulic pressure of the retarded angle side hydraulic 2 within 7.

Further, when the duty ratio is set to 55% to 60%, the ring gear 25 does not move to either the advance side or the retard side, and stops at that position. At this time, the hydraulic pressure in the advance hydraulic chamber 26 is larger than the hydraulic pressure in the retard hydraulic chamber 27. This is because the difference hydraulic pressure balances the thrust force of the ring gear 25 and stops the ring gear 25.

Next, the operation of the valve timing control device configured as described above will be described with reference to the flowchart shown in FIG. First, in step 101, the ECU
Reference numeral 71 determines whether or not an idle switch provided on the accelerator pedal or the like is on. Next, when the idle switch is on, at step 102, the engine GN
Is less than or equal to the idle speed α (for example, 1000
rpm). In step 101,
If the idle switch is on and step 102
If the engine speed is equal to or lower than the predetermined speed, the ECU 71 determines that the engine is in an idle state, and proceeds to step 108. Also, in step 101,
If the idle switch is off or step 10
If the engine speed is equal to or higher than the idle speed α in step 2, the routine proceeds to step 103.

In step 103, it is determined whether the transmission connected to the engine is an automatic shift or a manual shift. Next, in step 104, if the transmission is an automatic shift, it is determined whether the position of the shift lever is in the neutral or parking position. In step 105, when the transmission connected to the engine is manual shift in step 103, it is determined whether or not the clutch is connected. Further, at step 106, it is determined whether or not the shift lever of the manual shift is at the neutral position.

If it is determined in step 104 that the automatic shift lever is in the neutral or parking position, if it is determined in step 105 that the clutch is not engaged in the manual shift, then in step 106,
If it is determined that the shift lever of the manual shift is at the neutral position, the process proceeds to step 108. Also, in step 104, when it is determined that the automatic shift lever is in a position other than neutral or parking, in step 106, it is determined that the shift lever for manual shift is in a position other than neutral. In this case, the process proceeds to step 107.

Steps 101 to 106 explained so far
Each step up corresponds to a particular operating condition detecting means.
That is, in the present embodiment, the target valve timing is set to the most retarded angle (the ring in the direction of the thrust force applied to the ring gear 25) under the condition of extremely light load and no load such as the operation at the idle rotation or the neutral state. (The gear stroke end), so that the above method is used.

In step 108, since it is determined that the engine operation state is light load, the retard control of the intake valve timing which is the valve timing suitable for the light load is performed. That is, the ECU 71 sets the drive current to the solenoid 53 of the OCV 44 to 0 (duty ratio 0%). Next, in step 109, the ECU 71
Based on the detection signals from 1 to 87, a target valve timing according to the engine operating state is obtained. And ECU
An actual valve timing 71 is obtained based on detection signals from the crank angle sensor 83 and the cam angle sensor 82. The ECU 71 determines a deviation based on the target valve timing and the actual valve timing, and determines whether the deviation is equal to or less than a predetermined value.

If the difference between the target valve timing and the actual valve timing is equal to or less than a predetermined value, it is determined that the ring gear 25 has moved to near the target valve timing, and the routine proceeds to step 110. If the difference between the target valve timing and the actual valve timing is equal to or more than the predetermined value, the process returns to step 108 again. Step 109 described here corresponds to the deviation determining means.

In step 110, after it is determined that the ring gear 25 has moved to the vicinity of the target valve timing, the differential pressure of the hydraulic pressure applied to the hydraulic chambers 26, 27 on both sides of the ring gear 25 changes in the direction against the thrust force. ECU 71 controls the lubricating oil pressure adjusting means so that the oil pressure is controlled so as to be equal to or less than the thrust force generated in the ring gear.
A predetermined drive current (for example, duty ratio 60
%)give. Therefore, the spool 52 of the OCV 44
Stops at an intermediate position as shown in FIG.

[0053] Step 110 described here corresponds to lubricate the hydraulic control unit. In step 107, since it is determined that the engine operation state is in the operation region other than the light load, the normal valve timing control is performed.
V44 is driven and controlled. That is, the target valve timing according to the current operating condition is calculated, the deviation from the current valve timing is obtained, the OCV driving current according to the difference is obtained, and the OCV driving current is supplied to the solenoid 53. Its solenoid 5
Numeral 3 is located at a stroke corresponding to the drive current, and supplies respective hydraulic pressures to hydraulic chambers 26 and 27 on both sides. Furthermore,
Feedback control is performed by the cam angle sensor 82,
Control is performed to achieve the target valve timing.

Then, the first discharge port 55 is connected to the supply port 54 and the common drain port 57, and the second discharge port 56 is connected to the supply port 54 and the common drain port 57. At this time, the lubricating oil supplied from the supply port 54 is more supplied to the first discharge port 55 than to the second discharge port 56. Also, the common drain port 57
Is discharged from the second discharge port 56 more than the first discharge port 55.

Therefore, the first from the supply port 54
The lubricating oil is supplied to the second head oil passages 8 and 9.
Further, the supply amount of the lubricating oil supplied from the first head oil passage 8 to the advance-side hydraulic chamber 26 depends on the amount of the lubricating oil supplied from the second head oil passage 9 to the retard-side hydraulic chamber 27. More than the supply. Therefore, the hydraulic pressure in the advance hydraulic chamber 26 is higher than the hydraulic pressure in the retard hydraulic chamber 27. Since the difference between the oil pressures is made equal to the thrust force of the ring gear 25, the ring gear 25 stops at that position.

Conventionally, as shown in FIG. 4D, when the ring gear 25 is located at the most retarded side, the OCV 44
The solenoid 35 is demagnetized to maximize the connection between the first head oil passage 8 and the drain 47, and maximize the connection between the second head oil passage 9 and the supply port 54. Therefore, all the lubricating oil in the advance hydraulic chamber 26 falls off, and air enters the advance hydraulic chamber 26.

However, according to the present invention, the lubricating oil is also supplied to the advance hydraulic pressure chamber 26, and the hydraulic pressure can be generated by the lubricating oil supplied into the advance hydraulic pressure chamber 26. Therefore, it is possible to prevent air from entering the advance side hydraulic chamber 26. Therefore, when the operating state of the engine GN changes from the idling state and the lubricating oil is supplied into the advance hydraulic chamber 26, the air does not enter the advance hydraulic chamber 26, so that the ring gear 25 It can be immediately moved to the advance side, and the responsiveness can be improved. As a result, the relative angle between the pulley body 11 and the camshaft 1 can be changed, and the opening / closing timing of the valve can be smoothly changed.

Since the duty ratio is 60%, the spool 52 has already moved by an amount corresponding to the duty of 60%. Therefore, if the duty ratio is 60% or more, the ring gear 25 can be advanced immediately. As a result, the responsiveness of the ring gear 25 can be improved.

In this embodiment, the case where the ring gear 25 is disposed at the most retarded side has been described. In addition, the ring gear 25 is the most advanced side (the ring gear 25 is the pulley body 11
At a position where the duty ratio is
The solenoid 5 is driven by an exciting current corresponding to 5% (the duty can be immediately retarded by setting the duty ratio to 54%).
By exciting the ring 3, the ring gear 25 can be maintained at the most advanced position, and the control responsiveness to the retard side can be improved. If the ECU 71 determines in step 102 that the automatic shift lever (not shown) is located at the parking or neutral position based on the detection signal from the lever position sensor 87, the ECU 71 proceeds to step 104,
The same processing as above is performed.

Further, as long as the automatic shift lever is not switched to the drive range based on the detection signal from the lever position sensor 87, the ECU 71 does not change the duty ratio which becomes 60% even if the operation state of the engine GN changes. Therefore, even if the rotation speed of the engine GN changes while the shift lever is located at the parking or neutral position, the ring gear 25 is located at the most retarded side. Therefore, the relative angle between the pulley body 11 and the camshaft 1 does not change. As a result, even if the shift lever is switched to the drive range, the engine GN
Can be reliably prevented from becoming unstable or the engine GN being stopped.

In this embodiment, the solenoid 53 of the OCV 44 is excited by an exciting current based on a duty ratio of 60%. The duty ratio is not limited to this, and the duty ratio may be set between 55% and 60% at which the ring gear 25 does not move to either the advance side or the retard side.

Further, the solenoid 53 of the OCV 33 is driven by an exciting current based on a duty ratio of 28% to 54%.
May be configured to be excited. In this case, the ring gear 25 can be reliably disposed at the end of the advance side hydraulic chamber 26 by the thrust force or the driving reaction force of the cam without stopping the ring gear 25 at that position. Also, the advance side hydraulic chamber 26
Since the lubricating oil is also supplied to generate hydraulic pressure, it is possible to prevent air from entering the advance hydraulic pressure chamber 26. As a result, responsiveness when moving the ring gear 25 to the advance side can be improved.

The advance hydraulic chamber 26 and the retard hydraulic chamber 2
The duty ratio may be set so long as the oil pressure can be generated by the lubricating oil supplied to each of the insides 7 and the ring gear 25 does not move to the advance side. Therefore, since the characteristics of the mechanism change depending on the configuration of the engine GN, the characteristics of the mechanism as shown in FIGS. The advance side hydraulic chamber 26 and the retard side hydraulic chamber 27
The oil pressure can be generated by the lubricating oil supplied to the inside, and the duty ratio at which the ring gear 25 does not move to the advance side may be determined and set from the characteristics.

Further, if any of the idling state of the engine GN, the parking position of the automatic shift lever, and the neutral position is detected, the ring gear 25
Is controlled to be the most retarded angle. After the ring gear 25 has been moved to a predetermined position, the duty ratio is
%. Then, the ring gear 25 is gradually moved to the most retarded side by the thrust force of the ring gear 25 and the driving reaction force of the cam.
Can also be configured to move.

In the present embodiment, the duty ratio is fixed after the ring gear 25 is moved to the retard side based on either the idling state or the position of the shift lever. In addition, after moving the ring gear 25 to the retard side only based on the idling state, fixing the duty ratio, or moving the ring gear 25 to the retard side only based on the position of the shift lever It is also possible to fix the duty ratio.

In the above-described embodiment, the idle switch, the number of revolutions, and the like are used as the light load state judging means. Alternatively, a throttle fully closed switch, a fuel injection amount, an intake air amount, and the like can be used. is there.

Further, the position of the ring gear when the engine is lightly loaded is set at the end in the direction of the thrust force generated by the rotation of the helical spline to the ring gear 25 as described above. In the case of the GN, in a light load state, the engine speed is low, that is, the lubricating oil pressure is often low, so that the time until the oil pressure in the hydraulic chambers 26, 27 rises to the oil pressure to overcome the thrust force is increased. However, the above-described embodiment solves such a problem.

[0068]

As described above in detail, according to the first aspect of the present invention, the ring gear is provided with the advance side hydraulic chamber or the retard side hydraulic chamber.
When placed near the end of the chamber, the arrangement of its ring gear
Since the lubricating oil is supplied to the hydraulic chamber on the side where the air flows, the intrusion of air is prevented, so that the responsiveness of the valve timing control can be improved .

[0069]

[0070]

According to the second aspect of the present invention, in the specific operating state of the engine, after the ring gear moves to a position near the target valve timing, the thrust is gradually increased by the differential pressure of the oil pressure on both sides of the ring gear. Move in the direction of force. Therefore, the hydraulic pressure is maintained after moving to the valve timing according to the specific operation state, and the response speed to the valve timing according to the specific operation state can be improved, and the response speed to the subsequent change in the operation state also improves. Can be done.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a valve timing control device according to the present invention and showing a state in which a ring gear is arranged on the most retarded side by OCV control.

FIG. 2 is a schematic configuration diagram illustrating a state in which a ring gear is arranged at a most advanced angle side under OCV control.

FIG. 3 is a schematic configuration diagram showing a state in which OCV is controlled so as to maintain a state in which a ring gear is arranged on the most retarded side.

4A is a characteristic diagram of a spool moving amount with respect to a duty ratio, FIG. 4B is a characteristic diagram of an advance side and a retard side hydraulic chambers with respect to a duty ratio, and FIG. FIG. 4 is a characteristic diagram showing a moving direction of a gear,
(D) is an explanatory view showing the conventional most retard control and the most retard control of the present invention.

FIG. 5 is a flowchart illustrating position control of a ring gear.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cam shaft, 10 ... Timing pulley as a pulley, 25 ... Ring gear, 26 ... Advance side hydraulic chamber, 27 ...
Retard-side hydraulic chamber 41, an oil pump constituting hydraulic pressure generating means 44, an OCV 71 as a lubricating hydraulic pressure adjusting means 71
ECU as timing control means, lubricating oil pressure control means and deviation determination means, 81: rotational speed sensor as operating state detecting means, 82, cam angle sensor as operating state detecting means and actual valve timing detecting means, 83, operating state A crank angle sensor as a detecting means and an actual valve timing detecting means; a throttle sensor as an operating state detecting means; a water temperature sensor as an operating state detecting means; an air flow meter as an operating state detecting means;
87: lever position sensor as operating state detecting means and lever position detecting means, GN: engine

Continuation of the front page (56) References JP-A-57-212310 (JP, A) JP-A-6-299812 (JP, A) JP-A-6-17618 (JP, A) JP-A-3-503197 (JP) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) F01L 1/34 F02D 13/02

Claims (2)

(57) [Claims] 1. A spline is formed on the inner and outer peripheral surfaces.
Ring gear at least one of which is a helical spline
Between the pulley and the camshaft, and
A to connect the pulley and camshaft,
The advance gear side hydraulic chamber and the retard angle are formed in the pulley by the ring gear.
Side oil pressure chamber to control the oil pressure of the lubricating oil from the oil pressure generation means.
The pressure is adjusted according to the degree of opening to advance the hydraulic chamber on the advance side and the hydraulic pressure on the retard side.
Operation control with oil control valve to supply to the room
Based on the engine operating state detected by the state detecting means.
Timing control of oil control valve opening
Means to control the lubricating oil to advance hydraulic chamber or retard oil
To the pressure chamber, based on the oil pressure of the supplied lubricating oil.
Move the ring gear in the axial direction of the camshaft,
And the camshaft to change the relative position
Valve timing control device
There are, real Bal for detecting an actual valve timing of the valve
And a target valve timing according to the operating state of the engine.
And the deviation from the actual valve timing is less than a predetermined value
Deviation determining means for determining that there is a ring gear position corresponding to the target valve timing
Is the end of the advance side hydraulic chamber or the retard side hydraulic chamber, and
To the effect that the deviation is not more than a predetermined value by the deviation determining means
On the condition that the ring gear is
The ring gear is moved to the hydraulic chamber in the axial direction of the camshaft.
So that lubricating oil is supplied with a hydraulic pressure that does not
Lubrication oil pressure control that controls the opening of the oil control valve
Means for controlling the valve timing. 2. A spline is formed on the inner and outer peripheral surfaces.
Ring gear at least one of which is a helical spline
Between the pulley and the camshaft, and
A to connect the pulley and camshaft,
The advance gear side hydraulic chamber and the retard angle are formed in the pulley by the ring gear.
Side oil pressure chamber to control the oil pressure of the lubricating oil from the oil pressure generation means.
The pressure is adjusted according to the degree of opening to advance the hydraulic chamber on the advance side and the hydraulic pressure on the retard side.
Operation control with oil control valve to supply to the room
Based on the engine operating state detected by the state detecting means.
Timing control of oil control valve opening
Means to control the lubricating oil to advance hydraulic chamber or retard oil
To the pressure chamber, based on the oil pressure of the supplied lubricating oil.
Move the ring gear in the axial direction of the camshaft,
And the camshaft to change the relative position
Valve timing control device
There are, real Bal for detecting an actual valve timing of the valve
And a target valve timing according to the operating state of the engine.
And the deviation from the actual valve timing is less than a predetermined value
Deviation determining means for determining that there is a ring gear position corresponding to the target valve timing
However, the rotation was caused by the rotation of the helical spline of the ring gear.
Identification of the end of the ring gear in the direction of the generated thrust force
The specific operating condition detecting means for detecting operating conditions, that is a specific operating condition by the particular operating condition-detecting means
Is detected and the deviation is determined by the deviation determination means.
Under the condition that it is determined that the pressure is equal to or less than the predetermined value,
The force generated in the ring gear by the differential pressure of the chamber is
Those who resist the thrust force with a size less than the last force
So that the oil control valve
Lubricating oil supplied to each hydraulic chamber by controlling the opening
A valve timing control device comprising: a lubricating oil pressure control unit .