JPH07189621A - Valve timing control device for internal combustion engine - Google Patents

Abstract

(57) [Abstract] [Purpose] It becomes possible to regulate the relative rotational positions of the rotating body and the cam shaft in multiple stages and at arbitrary positions, and obtain stable and highly accurate control of valve timing. [Configuration] It is premised that the relative rotational phase of the pulley 1 and the camshaft 2 can be converted as the tubular gear 8 moves in the front-rear direction. Between the pulley body 13 and the sleeve 6,
The spring force of the disc spring 29 causes the first gear portion 27 and the second gear portion 28 to move.
A gear lock mechanism 10 for engaging and locking the gears is provided. Further, the release mechanism 11 is provided for temporarily releasing the lock by separating the first gear portion 27 from the first gear portion 27 by the attraction force of the electromagnet 30 when the both 1 and 2 rotate relative to each other.

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 for variably controlling the opening / closing timing of intake / exhaust valves of an internal combustion engine according to the operating conditions.

[0002]

2. Description of the Related Art Various conventional valve timing control devices of this type have been provided, and an example thereof is disclosed in Japanese Patent Application Laid-Open No. 3-286104.

In brief, a sprocket is provided with a rotational force transmitted from a crankshaft of an engine through a timing chain, and a camshaft having a cam for opening and closing intake / exhaust valves by the rotational force of the sprocket.
The sprocket has inner teeth formed on the inner peripheral surface of a tubular body, while outer teeth are formed on the outer periphery of one end of a cam shaft inserted and arranged in the tubular body. A tubular gear that is movable in the axial direction of the camshaft is interposed between the tubular body and one end of the camshaft. The tubular gear has inner and outer teeth and outer teeth on the inner and outer circumferences. At least one of the teeth has a helical tooth-shaped inner and outer teeth that mesh with the teeth.

Then, the tubular gear is adapted to the engine operating condition by the hydraulic pressure supplied from the hydraulic circuit in the pressure chamber formed inside the front end of the sprocket or the spring pressure of the compression spring provided opposite to the pressure chamber. By moving the camshaft in the axial direction of the camshaft, the camshaft is rotated relative to the sprocket to control the opening / closing timing of the intake / exhaust valves.

[0005]

However, in the above-mentioned conventional valve timing control device, the tubular gear is moved in one direction or the other direction by the relative pressure between the hydraulic pressure in the pressure chamber and the spring force of the compression spring. Thus, the sprocket and the camshaft are controlled in two steps, that is, the maximum relative rotation position on one side and the maximum relative rotation position on the other side. In other words, since the movement of the cylindrical gear is controlled only by ON-OFF switching control, the sprocket and the cam shaft are also subjected to only two-stage relative rotational phase conversion on one side or the other side, so that the valve timing is set to the engine. Accurate control is not possible depending on the operating condition.

Therefore, it has been considered that the hydraulic pressure in the pressure chamber is controlled to stop the tubular gear at an arbitrary intermediate position, thereby controlling the valve timing in multiple stages. The characteristics such as viscosity easily change due to changes in the temperature and the engine speed, and it is extremely difficult to keep the oil pressure constant. For this reason, it becomes difficult to reliably control the moving position of the cylindrical gear at the intermediate position, which may lead to instability of the valve timing control.

[0007]

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned problems of the prior art. The invention of claim 1 relates to a rotating body which is rotationally driven by an engine, and the rotating body. A camshaft that is provided so as to be rotatable relative to one another and has a cam on its outer periphery that operates an intake / exhaust valve by a rotational force from a rotating body, and is interposed between the rotating body and the camshaft,
In a valve timing control device comprising a phase conversion means for converting a relative rotational phase of the both and a drive mechanism for driving the phase conversion means in accordance with an engine operating state, a front end portion of the rotary body and the rotary body are A gear lock mechanism is provided between the inserted camshaft and one end of the camshaft to regulate the relative rotation angular position of the camshaft and a release mechanism that unlocks the gearlock mechanism when the two rotate relative to each other. The feature is that it is provided.

According to a second aspect of the present invention, the gear lock mechanism is provided slidably in the axial direction on the outer periphery of one end of the camshaft and the first gear portion provided on the front end surface of the rotating body. It is characterized in that it is provided with a second gear portion that is engaged with and disengaged from the first gear portion, and a biasing means that biases the second gear portion toward the first gear portion.

According to a third aspect of the present invention, the release mechanism is provided on the back side of the second gear portion, and the second gear portion is provided with the first gear portion.
It is characterized in that it is provided with an electromagnet that attracts in a direction away from the gear portion, and a controller that energizes the electromagnet when the rotating body and the cam shaft rotate relative to each other.

According to a fourth aspect of the present invention, the release mechanism includes a pressure receiving chamber formed between the first gear portion and the second gear portion,
A hydraulic circuit that supplies hydraulic pressure to the pressure receiving chamber to move the second gear portion away from the first gear portion, an electromagnetic switching valve that switches the hydraulic circuit between a supply side and a discharge side, a rotor and a camshaft. And a controller for switching and operating the electromagnetic switching valve at the time of relative rotation.

[0011]

According to the inventions of claims 1 to 3, for example, when the engine is under a low load, the phase conversion means is held at the moving position in at most one direction by the drive mechanism so that the relative rotational phase between the rotating body and the camshaft is on one side. Convert to. At this relative rotational angle position on one side, the electromagnet is not energized from the controller, so the second gear portion is biased toward the first gear portion side by the biasing means, and both gear portions mesh and lock. As a result, free relative rotation between the rotating body and the cam shaft is restricted, and the relative rotation position is reliably held.

Further, at the same time when the engine load increases to a predetermined range, the electromagnet is energized from the controller to attract the second gear portion against the urging force of the urging means, thereby engaging with the first gear portion, that is, locking. The state is temporarily released. Therefore, the movement of the phase conversion means by the drive mechanism in the other direction is permitted, and the phase conversion means moves by a predetermined amount. As a result, when the rotating body and the camshaft relatively rotate to the other side and reach the predetermined relative rotation angle position, the electromagnet is de-energized and the suction to the second gear portion is stopped.
Therefore, the second gear portion can be meshed and locked with the first gear portion by the urging means, and the rotating body and the cam shaft can be reliably regulated and held at a desired relative rotation angle position. .

Further, as the load on the engine increases, the relative rotational angle position between the rotor and the camshaft can be reliably maintained at any multi-step position by the same operation as described above.

According to the first, second and third aspects of the present invention, the supply / discharge control of the hydraulic pressure from the hydraulic circuit to the pressure receiving chamber is performed by the switching operation of the electromagnetic switching valve from the controller according to the change in the engine operating state as described above. Then, the second gear portion and the first gear portion are locked or unlocked by relative operation with the biasing means. As a result, the rotary body and the cam shaft can be reliably regulated and held at a desired relative rotation angle position.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the valve timing control device of the present invention is applied to the intake valve side of a DOHC type internal combustion engine will be described in detail below with reference to the drawings.

FIG. 1 shows a first embodiment of the invention of claims 1 to 3. That is, in the figure, 1 is a pulley which is a rotating body to which a rotational force is transmitted from a crankshaft of an engine through a timing belt, and 2 is a cam bracket 4 above a cylinder head 3.
A camshaft having a cam for opening and closing an intake valve (not shown) on the outer periphery of the camshaft, which is supported through the camshaft 2. The camshaft 2 is inserted into the pulley 1 at one end 5a of the camshaft body 5. A sleeve 6 is fixed in the axial direction by bolts 7. A pin 51 for an angle detection sensor, which will be described later, is press-fitted in the shaft portion of the camshaft 2 in a direction perpendicular to the axis. Further, in the figure, 8 is a cylindrical gear that is interposed between the sleeve 6 and the pulley 1 and is a phase conversion means that is movable in the axial direction of the cam shaft 2, and 9 is a cylindrical gear 8.
Drive mechanism for moving the engine in the front-rear axis direction according to the engine operating state, 10 is a gear lock mechanism provided between the front end of the pulley 1 and the front end of the sleeve 6, and 11 is a lock of the gear lock mechanism 10. It is a release mechanism for releasing.

The pulley 1 is integrally provided on a cylindrical pulley main body 13 having an annular front cover 12 fixed to the front end thereof, and an outer peripheral surface of the pulley main body 13 on the rear end side. And teeth 14 to be wound. Further, the pulley body 13 has one end portion 5 of the camshaft body 5 via a retainer 15 which is caulked and fixed to the rear end portion.
The inner teeth 13a are formed on the inner peripheral surface of the front end side while being rotatably supported by a. The front cover 12
The outer peripheral edge projection is fitted into a groove formed in the inner periphery of the front end flange portion of the pulley body 13 and is prevented from rotating with respect to the pulley body 13.

The sleeve 6 has a cylindrical fitting portion 6a which is fitted to the one end portion 5a of the camshaft main body 5 at the rear end portion thereof, and the insertion hole 6b for the bolt 7 is formed at the center of the inner peripheral partition wall. Are formed so as to penetrate therethrough in the axial direction, and external teeth 6 are formed on the outer circumference of the front end side.
c is formed. Further, in the sleeve 6, the front end portion 6d having a small diameter step is formed in the central hole 12a of the front cover 12.
A guide groove 6e is formed on the outer periphery of the front end portion 6d so that a second gear portion 28, which will be described later, fits in a spline shape and guides in the axial direction. A lid 17 is screwed and fixed to the opening of the front end portion 6d of the sleeve 6 via a seal ring 16.

The tubular gear 8 is composed of front and rear gear components 8a and 8b formed by dividing a long gear in a direction perpendicular to the axis, and the gear components 8a and 8b are interposed between each other. The elastic member is elastically connected to each other through a connecting pin and a spring, and the inner teeth 1 are formed on the inner and outer circumferences.
Inner teeth and outer teeth of helical teeth, both of which mesh with the outer teeth 3a and the outer teeth 6c, are formed.

Further, the tubular gear 8 is composed of the front gear forming portion 8a.
Is restricted from moving in the maximum forward direction at a position where it hits the inner end surface of the front cover 12, while the rear gear component 8b
The rearward movement of the retainer 15 is restricted at a position where it hits the inner end surface of the retainer 15.

The drive mechanism 9 is elastically mounted between the rear gear forming portion 8b and the retainer 15 to urge the cylindrical gear 8 in the forward direction, and the front gear forming portion 8
pressure chamber 19 formed between a and the front cover 12.
And a hydraulic passage 21 that supplies and discharges hydraulic pressure through a through hole 20 that is formed in the pressure chamber 19 in the circumferential wall of the front end of the sleeve 6 along the radial direction.

An upstream side of the hydraulic passage 21 is connected to an oil pump 23 via an oil main gallery 22, and a three-way switching solenoid valve 24 is provided between the oil main gallery 22 and the hydraulic passage 21. ing. The switching solenoid valve 24 connects the oil main gallery 22 and the hydraulic passage 21 and closes the drain passage 25, or connects both the oil main gallery 22 and the hydraulic passage 21 to the drain passage 25. It is designed to be switched, and this switching is performed by the controller 2
6 is output by the ON-OFF control current.

The controller 26 has a built-in microcomputer that indicates a current engine operating state based on output signals from a crank angle sensor, an air flow meter, a water temperature sensor, a throttle valve opening sensor, a vehicle speed sensor, etc. (not shown). When the engine load is low, an OFF signal is output to the switching solenoid valve 24, and otherwise an ON signal is output. Further, the controller 26 detects the relative rotation angle between the pulley 1 and the camshaft 2 based on an output signal from a predetermined angle detection sensor 50 (electromagnetic pickup), and based on this angle information, the release mechanism 11 The control current is appropriately output to.

The gear lock mechanism 10 includes a first gear portion 27 integrally provided on the front end surface of the front cover 12,
A second gear portion 28 that is disposed so as to face the first gear portion 27 and that engages with and disengages from the first gear portion 27 while sliding in the axial direction;
It is composed of a disc spring 29 which is a biasing means for biasing the gear portion 28 toward the first gear portion 27.

The first and second gear portions 27 and 28 are formed in an annular shape, respectively, and tooth flanks 27a and 28 are meshed with each other.
a is formed in the shape of a spur gear along the radial direction as shown in FIG. 2, and the tip of each tooth crest 27a, 28a ensures good meshing with the facing tooth groove 27b, 28b. It is formed in an acute angle. In addition, the second gear portion 28
The sleeve 6 on the inner peripheral surface of the annular base portion 28c on the inner peripheral side.
A protrusion is formed along the axial direction that fits in the guide groove 6e and secures the movement in the axial direction.

As shown in FIG. 1, the disc spring 29 has an inner peripheral portion elastically contacting an annular retainer fixed to the front end portion 6d of the sleeve 6, and an outer peripheral portion formed on the outer periphery of the annular base portion 28c. The second gear portion 28 is biased toward the first gear portion 27 by elastically contacting the bottom surface of the annular groove.

The release mechanism 11 is provided on the back side of the second gear portion 28, and the second gear portion 28 is connected to the first gear portion 27.
Electromagnet 3 that is attracted in the direction away from
0 and the above-mentioned controller 26 for energizing / de-energizing the electromagnet 30.

The electromagnet 30 includes an electromagnetic coil 30a fixed to a rocker cover or the like via a fixing plate 31,
An annular core 3 fixed to the front end of the electromagnetic coil 30a via a holder 32 and facing the back surface of the second gear portion 28.
0b and. Further, a ball bearing 33 that rotatably supports the sleeve 6 is provided between the holder 32 and the front end portion 6d of the sleeve 6.

Reference numeral 34 in the figure denotes an oil seal for preventing the hydraulic oil leaking between the camshaft body 5 and the retainer 15 from being discharged to the outside.

The operation of this embodiment will be described below.
First, for example, when the engine load is low, an OFF signal is output from the controller 26 to the switching solenoid valve 24 to connect the oil main gallery 22 and the hydraulic passage 21 to the drain passage 25. Therefore, the tubular gear 8 is held at the maximum forward position (the illustrated position) by the spring force of the compression spring 18 as the pressure inside the pressure chamber 19 is reduced. Therefore, the relative rotational angle position between the pulley 1 and the camshaft 2 is converted to one direction at the maximum, and the closing timing of the intake valve is retarded.

At this time, the controller 26 outputs an OFF signal (non-energized) to the electromagnetic coil 30a, and the core 3
The suction of the second gear portion 28 by 0b is released. Therefore, the second gear portion 28 moves to the right in the drawing via the guide groove 6e by the spring force of the disc spring 29, meshes with the first gear portion 27, and locks. Therefore, the pulley 1 and the camshaft 2 are prevented from freely rotating relative to each other, and are reliably held at the maximum relative rotation position on one side.

When the engine load increases in a predetermined range, an ON signal (energization) is simultaneously output from the controller 24 to the electromagnetic coil 30a, and the switching electromagnetic valve 24 is also turned ON.
The signal is output.

Therefore, the second gear portion 28 is connected to the core 30b.
Is sucked by and is moved to the left in the figure against the spring force of the disc spring 29 to temporarily disengage from the first gear portion 27,
Allows free relative rotation between the pulley 1 and the camshaft 2.

On the other hand, the drain passage 25 is closed by the switching operation of the switching solenoid valve 24, and the oil main gallery 22 and the hydraulic passage 21 are communicated with each other. Therefore, the hydraulic fluid pumped from the oil pump 23 flows into the pressure chamber 19 through the hydraulic passage 21, and the tubular gear 8 resists the spring force of the compression spring 18 as the hydraulic pressure of the pressure chamber 19 rises. It moves backward and changes the relative rotational angular position between the pulley 1 and the camshaft 2.

When a predetermined relative rotation angle position (for example, about 10 °) is reached, the controller 2 which detects this position
An OFF signal is output from 6 to the electromagnetic coil 30a. Therefore, the second gear portion 28 moves rightward and meshes with the first gear portion 27 to be locked. As a result, free relative rotation between the pulley 1 and the camshaft 2 is restricted,
2 is securely held in such a relative rotation angle position. Therefore, the closing timing of the intake valve is controlled slightly to the advanced side to match the operating state, and the engine performance can be improved.

When the engine load further increases, the controller 26 outputs the ON signal to the electromagnetic coil 30a again, the meshing of the second gear portion 28 and the first gear portion 27 is temporarily released, and the pulley 1 and the cam shaft are released. Allows relative rotation with 2. Therefore, when the tubular gear 8 is moved further rearward by the hydraulic pressure in the pressure chamber 19 to relatively rotate the both 1, 2 to a predetermined angular position (for example, 20 °), the electromagnetic coil 30a is moved to the electromagnetic coil 30a as described above. The OFF signal is output and the second
The gear portion 28 meshes with the first gear portion 27 and locks. Therefore, the both 1 and 2 are securely held in the relative rotational angle position.

Further, as the engine load increases, the electromagnet 30 is repeatedly operated in the same manner as described above, so that the both 1 and 2 can be reliably held at an arbitrary relative rotation angle position. Therefore, it is possible to change the valve timing in multiple stages, which enables highly precise control according to the operating state of the engine and stable control.

FIG. 3 shows a second embodiment of the present invention, in which the first gear portion 27 and the second gear portion 28 are provided inside the pulley body 13, and the core 30b of the electromagnet 30 is provided inside the front cover 12. It is a thing. That is, the first gear portion 27
Has an approximately U-shaped cross section, and an annular cutout groove 13b in which a cylindrical outer peripheral portion 27c is formed on the inner peripheral surface on the front end side of the pulley body 13.
It is press-fitted and fixed to the inner peripheral surface of the. On the other hand, the second gear portion 28
Has substantially the same structure as that of the first embodiment, but is entirely arranged inside the front cover 12, and the back surface is the core 30b.
Is facing. In addition, the pressure chamber 19 has two gear parts 27,
28 and the front gear component 8a.

In the electromagnet 30, an electromagnetic coil 30a is fixed to a rocker cover or the like via a fixing plate 31, and a front end portion of the electromagnetic coil 30a is formed in an annular projection projecting on the inner and outer circumferences of the front end surface of the front cover 12. Parts 12b, 12
It is held between c and arranged close to the core 30b with a minute gap.

A communication passage 3 for connecting the hydraulic passage 21 and the pressure chamber 19 to the crank-shaped bent portion of the second gear portion 28.
6 is formed, and the communication passage 36 is formed by the second gear portion 2
When the through hole 20 is closed by the base portion 28c when 8 is moved to the first gear portion 27 side, the pressure chamber 1 from the hydraulic passage 21 is closed.
The hydraulic oil is made to flow into the No. 9.

The other structure is the same as that of the first embodiment.
Therefore, according to the present embodiment, it goes without saying that the same effects as those of the first embodiment can be obtained, and each gear portion 27, 2
8 is housed in the pulley body 13 so that the sleeve 6
Since it is possible to shorten the length, it is not necessary to support the tip of the sleeve 6 with a bearing as in the first embodiment. Moreover, since the electromagnetic coil 30a is held by the annular projections 12b and 12c of the front cover 12, a holder is required. Therefore, the axial length of the device can be shortened, the number of parts can be reduced, and the structure can be simplified. As a result, the manufacturing work efficiency can be improved and the manufacturing cost can be reduced.

FIG. 4 shows a third embodiment of the present invention, in which the spring member for urging the second gear portion 28 in the right direction is replaced by a disc spring and a small diameter coil spring 35 with good manufacturability is used. . Further, the communication passage 34 is formed so as to penetrate in the inner axial direction of the base portion 28c where the coil spring 35 is located.

FIG. 5 shows an embodiment according to the first, second and fourth aspects of the invention, in which the release mechanism 11 is replaced by an electromagnet and hydraulically controlled.

That is, the releasing mechanism 11 is provided with the first gear portion 2
7 and the second gear portion 28, the pressure receiving chamber 40 that moves the second gear portion 28 in the direction away from the first gear portion 27 by the internal hydraulic pressure, and the hydraulic pressure is supplied to and discharged from the pressure receiving chamber 40. The hydraulic circuit 41, the electromagnetic switching valve 42 provided on the upstream side of the hydraulic circuit 41, and the controller 43 for switching and operating the electromagnetic switching valve 42.

The first gear portion 27 forming the pressure receiving chamber 40.
Is press-fitted and fixed via a seal ring 44 between the inner peripheral surface of the front end of the pulley body 13 and the stepped front end portion 6d of the sleeve 6, while the second gear portion 28 is provided with a pressure receiving chamber 40 on the outer periphery.
Is provided with a seal ring 53.

The hydraulic circuit 41 has a control passage 45 formed at the same position as the hydraulic passage 21 in the above-described embodiment, and a control passage 4 formed by penetrating in the central axial direction of the first gear portion 27.
Communication hole 4 for communicating the pressure receiving chamber 40 with the pressure receiving chamber 40 through the oil chamber 46.
7 and 7. The control passage 45 is formed in the cylinder head 3, and is formed in the radial direction of the cam shaft body 5 and the internal axial direction of the bolt 7. The above-mentioned hydraulic passage 21 is formed substantially parallel to the control passage 45, is formed inside the cylinder head 3 and in the radial direction of the camshaft main body 5, and as shown in FIG. It is formed between the arcuate groove 48 notched in the axial direction of the outer peripheral surface and the inner peripheral surface of the bolt insertion hole.
The hydraulic passage 21 communicates with the pressure chamber 19 formed by the outer peripheral groove of the rear gear component 8b through a through hole 49 formed in the peripheral wall of the sleeve 6 in the radial direction.

The electromagnetic switching valve 42 switches between a supply side for communicating the oil main gallery 22 and the control circuit 45 and a discharge side for opening the drain passage 50.

The controller 43 controls the switching solenoid valve 24 in accordance with the change in engine operation as described above, and at the same time, the solenoid switching valve is detected based on the signal detecting the relative rotation angle between the pulley 1 and the camshaft 2. 42 is ON-OFF controlled.

A leak passage 51 is formed in the peripheral wall of the pulley body 13 for allowing the hydraulic oil leaking from the pressure receiving chamber 40 to flow into the chamber in which the compression spring 18 is mounted.

The operation of this embodiment will be described below.
First, when the engine load is low, the tubular gear 8 is moved to the maximum forward position by the spring force of the compression spring 18 as the pressure inside the pressure chamber 19 is reduced, and the pulley 1 and the cam shaft 2 are moved to one side. To the relative rotation position of. Here, when the OFF signal is output to the electromagnetic switching valve 42, the hydraulic oil in the pressure receiving chamber 40 flows back through the control passage 45 and is discharged from the drain passage 50 into the oil pan 52, so that the pressure receiving chamber 40 becomes low in pressure. Become. Therefore, the second gear portion 28 is moved toward the first gear portion 27 side by the spring force of the coil spring 35 serving as the biasing means and meshingly locked. Therefore, the both 1 and 2 are securely held in the relative rotational position.

When the engine load increases, an ON signal is output from the controller 43 to the electromagnetic switching valve 42 and the switching electromagnetic valve 24, the drain passages 25 and 50 are closed, and the oil main gallery 22 and the oil main gallery 22 are connected. Hydraulic passage 21,
The control passages 45 communicate with each other. Therefore, the pressure receiving chamber 40
As the hydraulic oil flows in to become high in pressure, the second gear portion 28 is moved leftward against the spring force of the coil spring 35, and the meshing lock with the first gear portion 27 is released. As a result, relative rotation of the both 1 and 2 is allowed.

At substantially the same time, the hydraulic pressure in the pressure chamber 19 rises to move the cylindrical gear 8 backward, changing the relative rotation angle between the two 1 and 2 to the other side to close the intake valve. To control the advance angle. Then, when the predetermined relative rotation angle position is reached, an OFF signal is output to the electromagnetic switching valve 42 and the hydraulic oil in the pressure receiving chamber 40 is discharged. Therefore, the second gear portion 28 moves to the right and meshes with the first gear portion 27 again to lock the first gear portion 27 and the first gear portion 27 at the relative rotation angle position.

Further, when the load on the engine is increased, the lock and release operations of the first and second gear portions 27 and 28 similar to those described above reliably hold the both 1 and 2 at a desired relative rotational angle position.

Therefore, improvement of valve timing control accuracy and stabilization control can be obtained. Further, since the same hydraulic pressure as that for moving the cylindrical gear 8 can be used, the manufacturing cost can be reduced as compared with the case where the electromagnet 30 is used.

Even when the engine is shifted from the high load range to the low load range, the desired relative rotation angle position can be reliably maintained by the same operation as described above.

The present invention is not limited to the above embodiment, and the relative rotational angle positions of the both 1 and 2 can be freely set according to the engine specifications and the like. Further, the phase conversion means is not limited to the cylindrical gear 8.

Further, the coil spring 35 is elastically mounted between the second gear portion 28 and the first gear portion 27, and the second gear portion 2
A hydraulic pressure may be applied to 8 so as to lock the mesh between the first and second gears.

[0058]

As is apparent from the above description, according to the present invention, the relative rotational position between the rotating body and the camshaft can be controlled in a plurality of stages of two or more stages, and of course any relative rotational position can be controlled. It will be possible to reliably regulate. As a result, the valve timing can be controlled with high accuracy according to the engine operating state, and stabilization control can be obtained.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment according to the invention of claims 1 to 3.

FIG. 2 is a view taken in the direction of arrow A in FIG. 1, showing a state in which both gear parts are meshed.

FIG. 3 is a cross-sectional view of essential parts showing a second embodiment of the present invention.

FIG. 4 is a cross-sectional view of an essential part showing a third embodiment of the present invention.

FIG. 5 is a vertical sectional view showing an embodiment according to claims 1, 2, and 4;

6 is a cross-sectional view taken along the line BB of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Pulley (rotating body) 2 ... Cam shaft 6 ... Sleeve (one end) 8 ... Cylindrical gear (phase conversion means) 10 ... Gear lock mechanism 11 ... Release mechanism 26 ... Controller 27 ... 1st gear part 28 ... 2nd Gear part 29 ... Belleville spring (biasing means) 30 ... Electromagnet 35 ... Coil spring (biasing means) 40 ... Pressure receiving chamber 41 ... Hydraulic circuit 42 ... Electromagnetic switching valve 43 ... Controller

Claims (4)

[Claims] 1. A rotating body which is rotationally driven by an engine, a camshaft which is provided so as to be rotatable relative to the rotating body, and has a cam on its outer periphery which operates an intake / exhaust valve by a rotational force of the rotating body, Valve timing control provided with a phase conversion means interposed between a rotating body and a cam shaft for converting a relative rotational phase of the both and a drive mechanism for driving the phase conversion means according to an engine operating state. In the device, a gear lock mechanism is provided between the front end of the rotating body and the one end of the cam shaft inserted through the rotating body to restrict the relative rotation angle position of the both, and when the both rotate relative to each other. A valve timing control device for an internal combustion engine, comprising: a release mechanism for releasing the lock of the gear lock mechanism. 2. The gear lock mechanism includes a first gear portion provided on a front end face of a rotating body and an outer periphery of one end portion of the cam shaft slidably in the axial direction. The second gear portion that engages and disengages, and a biasing unit that biases the second gear portion toward the first gear portion side are provided.
A valve timing control device for an internal combustion engine as described above. 3. The release mechanism is provided on the back side of the second gear portion, and attracts a magnet in a direction separating the second gear portion from the first gear portion, and the electromagnet has a rotating body and a cam. 3. The valve timing control device for an internal combustion engine according to claim 1, further comprising a controller that energizes when the shaft rotates relatively. 4. The release mechanism includes a first gear portion and a second gear portion.
A pressure receiving chamber that is formed between the pressure receiving chamber and the gear unit and moves the second gear unit in the direction of separating from the first gear unit by the internal hydraulic pressure; a hydraulic circuit that supplies and discharges the hydraulic pressure to and from the pressure receiving chamber; 3. An internal combustion engine according to claim 1 or 2, further comprising: an electromagnetic switching valve that switches between a supply side and a discharge side; and a controller that switches and operates the electromagnetic switching valve when the rotating body and the camshaft rotate relative to each other. Valve timing control device.