JPH116405A - Variable valve timing mechanism for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a variable valve timing mechanism, easily and adequately disassembled/reassembled from/to a cam shaft, by preventing the dislocation of the rotation axis center of first and second rotation bodies due to operating a lock mechanism. SOLUTION: In a variable valve timing mechanism 11 with a lock mechanism, limiting the relative rotation between a cam shaft 12 and a cam gear 18 in a given rotation phase; an insertion bore 38 and a screw hole 39 are formed on a front surface cover 22 and an inside rotor 14 respectively so as to be communicated and overlapped with each other in a specific rotation phase where the lock mechanism is operated. In disassembling work, a fastening bolt 40 is threadedly attached into the hole 39 via the bore 38 previously, thereby fixing the rotation axis center of the inside rotor 14 and a housing 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake engine for an internal combustion engine.
The present invention relates to a variable valve timing mechanism for an internal combustion engine that makes opening and closing timing of an exhaust valve variable, and more particularly to a vane type variable valve timing mechanism having a lock mechanism.

[0002]

2. Description of the Related Art A variable valve timing mechanism of an internal combustion engine changes the rotation phase of a camshaft to change the intake / intake timing.
The opening and closing timing of the exhaust valve is adjusted. This mechanism makes it possible to optimize the opening and closing timing of the valve according to the operating state of the internal combustion engine, such as the load and the number of revolutions. Therefore, it is possible to improve the fuel efficiency, output, emission, and the like of the internal combustion engine over a wide range of operating conditions.

There are various types of such variable valve timing mechanisms.
An example thereof is a "valve opening / closing adjusting device" described in Japanese Patent Publication No. 4 (JP-A) No. 4 (1994).

[0004] A variable valve timing mechanism of the type disclosed in the above-mentioned publication discloses a first rotating body that rotates integrally with a camshaft, a driven gear that is drivingly connected to a crankshaft of an internal combustion engine, and an integral rotation. And a second rotating body.

A vane formed on the other rotating body is disposed in a recess formed on one of the rotating bodies. By dividing the recess by the vane, first and second hydraulic chambers are formed on both sides of the vane.

[0006] By changing the hydraulic pressure in the first and second hydraulic chambers, the two rotating bodies are relatively rotated. Due to this relative rotation, the rotational phase of the camshaft and the driven gear changes, so that the opening / closing timing of the intake / exhaust valves driven to open / close by the camshaft can be changed.

The variable valve timing mechanism configured as described above is generally called a "vane type variable valve timing mechanism".
It is called. In this vane type variable valve timing mechanism, there is a case where the supply of the hydraulic pressure to the variable valve timing mechanism cannot be sufficiently performed at the time of starting the internal combustion engine or the like, and the operation of the variable valve timing mechanism may become unstable. is there. In order to prevent this, in the variable valve timing mechanism, when the hydraulic pressure supplied to the hydraulic chamber is not sufficient, such as immediately after the start of the internal combustion engine, the relative rotation of the two rotating bodies is fixed. Some devices have a lock mechanism.

The lock mechanism is provided in a locking hole formed in one of the two rotating bodies and an arrangement hole formed in the other, and is urged by a coil spring, a hydraulic pressure or the like. Thus, a mechanism constituted by a lock pin that can be fitted into the locking hole is widely used.

[0009]

When performing an inspection or repair, the variable valve timing mechanism may be once removed from the camshaft and then re-assembled on the same shaft.

[0010] Some of the variable valve timing mechanisms are adjusted so that the rotation axes of the first and second rotating bodies become the same axis by being assembled to the camshaft. In such a variable valve timing mechanism, when the rotary shaft is removed from the camshaft, the rotation axes of the first and second rotating bodies are no longer regulated, and the rotation axes of the two rotating bodies may be misaligned. .

On the other hand, the above-described removal and reassembly work is performed while the internal combustion engine is stopped. In the vane type variable valve timing mechanism having the above-described lock mechanism, when the internal combustion engine is stopped, the relative rotation between the two rotating bodies is restricted by the lock mechanism. Therefore, when the variable valve timing mechanism is removed from the camshaft and the lock mechanism is operated in a state where the rotational axes of the two rotating bodies are displaced as described above, the state in which such deviation occurs Therefore, both the rotating bodies may be fixed. Once the two rotating bodies are fixed in a state where the rotational axes of the two rotating bodies are displaced in this way, it is very difficult to re-assemble the removed variable valve timing mechanism to the camshaft. It will be difficult. Even if the variable valve timing mechanism can be assembled, the original operation of the variable valve timing mechanism may be unstable, such as the first and second rotating bodies being mounted diagonally, or the lock mechanism being stuck and being unable to be released. May be.

The present invention has been made in view of such circumstances, and an object of the present invention is to prevent the rotation shafts of both of the rotating bodies from being displaced by the operation of a lock mechanism, thereby enabling removal from a camshaft. It is an object of the present invention to provide a variable valve timing mechanism for an internal combustion engine that can easily and accurately perform an operation and a re-assembly operation to the shaft, and further ensure a stable operation after the re-assembly.

[0013]

In order to achieve the above object, according to the first aspect of the present invention, one of a camshaft having the same rotation axis and an output shaft of an internal combustion engine and a valve for opening and closing a valve of the engine is provided. And the first and second connected to the other
And the first and second liquid chambers are formed on both sides of the vane by dividing the recess formed in the second rotor with the vane formed in the first rotor. And a variable valve timing mechanism for an internal combustion engine that changes the relative rotation phase between the engine output shaft and the camshaft by relatively rotating the first and second rotating bodies based on the hydraulic pressure control for the formed liquid chamber. The first and second rotating bodies are locked in a specific rotation phase based on the biasing force of the biasing means, and are locked based on the fluid pressure supplied to at least one of the first and second fluid chambers. And a fastening means for fastening the first and second rotating bodies so as to be freely released in a specific rotation phase locked by the lock mechanism.

According to this structure, the first and second rotating bodies can be fastened to the specific rotation phase locked by the lock mechanism through the fastening means.
By fastening the first and second rotating bodies in this manner, the lock mechanism is further biased when the rotating body is removed from the camshaft for repair, inspection, or the like. As a result, it is possible to preferably prevent the rotation axes of the first and second rotating bodies from being displaced from each other, so that the operation of reassembling the camshaft can be reliably performed. In addition, since the reassembly operation to the camshaft is performed reliably, stable operation as the variable valve timing mechanism is also ensured. The fastening state of the above-mentioned fastening means is arbitrarily released after the operation of attaching the first and second rotating bodies to the camshaft is completed.

According to a second aspect of the present invention, in the configuration of the first aspect of the present invention, the fastening means includes the first and the second in a specific rotation phase locked by the lock mechanism. A communication hole is formed between at least one of the first and second rotating bodies, and a communication hole is formed between the rotating bodies, and a screw is formed in the communication hole.

According to the above configuration, the first bolt is screwed into the communication hole, and the first bolt is screwed into the communication hole.
In addition, the second rotating body can be easily and accurately fastened. Further, the above-mentioned fastening state can be released by a simple operation of simply removing the bolt from the communication hole. Furthermore, according to the configuration, since the fastening state is not inadvertently released, the fastening state can be suitably maintained even when the variable valve timing mechanism alone is conveyed. In the case of the same configuration, it can be easily adopted in an existing variable valve timing mechanism.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a variable valve timing mechanism according to the present invention will be described below in detail with reference to FIGS.

First, an outline of a vane type variable valve timing mechanism with a lock mechanism, which is the basis of the present embodiment, will be described with reference to FIGS. FIG. 4 is a side sectional view of the vane type variable valve timing mechanism 11 with a lock mechanism. A camshaft 12 to which the mechanism 11 is assembled is rotatably supported by an upper end surface of a cylinder head 13 of the engine and a bearing cap 23. An internal rotor 14 as a first rotating body is attached to a tip of the camshaft 12 by a center bolt 15 so as to be integrally rotatable with the shaft 12.

The outer circumference of the internal rotor 14 is covered by a housing 16 that can rotate relative to the rotor 14. Further, the housing 16 includes a plurality of mounting bolts 1.
7, a cam gear or a sprocket or a timing pulley (hereinafter simply referred to as "cam gear") 1
8 and the front cover 22 so as to be integrally rotatable. The cam gear 18 is drivingly connected to a crankshaft (not shown) which is an output shaft of the engine via a chain, a timing belt and the like (not shown).

FIG. 5 shows the variable valve timing mechanism 1.
1 shows a front sectional view of FIG. A plurality of (four in the example) vanes 19 protruding in the radial direction of the inner rotor 14 are provided on the outer peripheral side surface of the inner rotor 14. A plurality of projections 2 are provided on the inner peripheral side of the housing 16.
No. 0 is provided, and the vane 19 is disposed in a portion (hereinafter referred to as a concave portion) 21 between the respective projecting portions 20. The tip of the vane 19 is the housing 16
The tip of the projection 20 is slidably in contact with the inner peripheral side surface of the internal rotor 14. Therefore, the internal rotor 14 and the housing 16 are relatively rotatable about the same rotation axis.

On the other hand, two spaces including pressure chambers 29 and 30 are formed on both sides of the vane 19 by the inner peripheral wall of the concave portion 21, the front cover 22 (FIG. 4) and the side surface of the vane 19. . Here, when viewed from the vane 19, the pressure chamber 30 formed in the rotation direction (clockwise in FIG. 5) of the camshaft 12 (FIG. 4) is a retard pressure chamber, and the pressure chamber 30 is formed in the opposite direction. The chamber 29 is referred to as an advanced pressure chamber.

As shown in FIG. 1, each hydraulic passage P1, P2
Is connected to an oil control valve (hereinafter referred to as “OCV”) 27. The OCV 27 is controlled by an electronic control unit (hereinafter referred to as “ECU”) 28 according to the operating state of the engine. Detection signals are sent to the ECU 28 from various sensors (not shown) such as a rotation speed sensor, an intake pressure sensor, a crank angle sensor, and a cam angle sensor. Based on these detection signals, the ECU 2
8 calculates the rotation phase angle (advance angle value) of the camshaft 12 suitable for the current operation state of the engine, judges the deviation between the target value of the rotation phase angle and the actual rotation phase angle, and The OCV so that the deviation is equal to or less than a predetermined value.
27 is controlled.

That is, if the actual rotation phase angle is later than the calculated rotation phase angle target value,
Reference numeral 28 controls the OCV 27 so that oil is supplied to the pressure passage P1 and oil is discharged from the pressure passage P2. Eventually, the hydraulic pressure in the advance side pressure chamber 29 increases, and the hydraulic pressure in the retard side hydraulic chamber 30 decreases. Accordingly, the internal rotor 14 rotates in the same rotational direction as the rotation of the camshaft 12 (hereinafter, this rotational direction is referred to as an “advance angle direction”), and the rotation of the shaft 12 that rotates integrally with the rotor 14. The phase is advanced with respect to the cam gear 18. That is, the opening and closing timing of the valve is advanced.

On the other hand, if the actual rotation phase angle is ahead of the calculated rotation phase angle target value, the above E
The CU 28 discharges oil from the pressure passage P1 and supplies oil from the pressure passage P2.
27 is controlled. Eventually, the hydraulic pressure in the advance side pressure chamber 29 decreases, and the hydraulic pressure in the retard side hydraulic chamber 30 increases. As a result, the internal rotor 14 rotates in a rotation direction opposite to the rotation of the camshaft 12 (hereinafter, this rotation direction is referred to as a “retard direction”). That is, the rotation phase of the shaft 12 that rotates integrally with the rotor 14 is delayed with respect to the cam gear 18, and the opening and closing timing of the valve is delayed.

If the deviation between the target value of the rotation phase suitable for the engine operating conditions and the actual rotation phase angle is equal to or less than a predetermined value, the ECU 28 shuts off the flow of oil into and out of the pressure passages P1 and P2. The OCV 27 is controlled. At this time, the relative rotation between the internal rotor 14 and the housing 16 is restricted by the oil pressure in the pressure chambers 29 and 30, and the opening and closing timing of the valve is fixed.

As described above, by controlling the pressure of the oil supplied to each of the pressure chambers 29 and 30, the opening / closing timing of the engine valve can be freely changed. FIG.
As shown in FIG. 5, a groove 24 having a rectangular cross section is formed at the tip of the vane 19 and the protrusion 20, and a sealing member 25 is provided in the groove 24.
Further, the member 25 is attached to the recess 2 by a leaf spring 26.
1 is urged toward the inner peripheral wall or the outer peripheral side surface of the internal rotor 14. As described above, the space between the tip of the vane 19 and the inner peripheral side surface of the housing 16 is sealed, and the movement of oil supplied between the advance side and the retard side pressure chambers 29 and 30 is regulated. Has become.

As schematically shown in FIG. 4, oil is supplied to these pressure chambers 29, 30 through respective hydraulic passages P1, P2. The internal rotor 14 rotates relative to the housing 16 about the rotation axis of the camshaft 12 in accordance with the magnitude of the oil pressure supplied to each of the pressure chambers 29 and 30.

The hydraulic pressure is supplied by an oil pump 31 which operates by rotation of a crankshaft of the engine. However, immediately after the operation of the engine is started, it is immediately after the oil pump 31 also starts to operate, so that sufficient oil pressure cannot be supplied to the OCV 27.
Therefore, the hydraulic pressure in each of the pressure chambers 29 and 30 may decrease, and the relative rotation between the internal rotor 14 and the housing 16 may not be restricted by the hydraulic pressure. Therefore, the vane 19 vibrates, and the housing 16
May collide with the projection portion 20 or an abnormal noise may be generated by the collision.

In order to prevent the occurrence of such a collision or abnormal noise, for example, the above-mentioned lock mechanism for restricting the relative rotation between the internal rotor 14 and the housing 16 in the most retarded phase is provided. I have.

Next, the specific structure of the lock mechanism will be described. As shown in FIGS. 4 and 5, one of the vanes 19 of the internal rotor 14 is provided with the camshaft 1.
2, a through hole 32 having a circular cross section extending in the axial direction is formed. The hole 32 is provided with a step part in the middle thereof, and the part on the front cover 22 side from the step part has an enlarged diameter.

Further, a lock pin 33 is inserted into the hole 32. The lock pin 33 has a bottomed tapered shape, and an enlarged diameter portion 33a is formed on the front cover 22 side. The lock pin 33 can move in parallel with the axis of the camshaft 12 with its outer peripheral side slidingly contacting the inner peripheral side of the through hole 32.

A pressure chamber 34 for releasing the locked state of the lock pin 33 is formed by an annular space surrounded by the inner peripheral wall of the through hole 32 having an enlarged diameter and the outer peripheral side surface of the lock pin 33. Is formed. This pressure chamber 34
It is connected to a hydraulic passage P1 that supplies hydraulic pressure to the advance pressure chamber 29, and can supply hydraulic pressure to the pressure chamber 34 simultaneously with the advance pressure chamber 29.

The inside of the lock pin 33 and the front cover 2
An accommodation space 35 extending in the axial direction is formed between the two, and a spring 36 is provided inside the accommodation space 35. The lock pin 33 is biased toward the cam gear 18 by the spring 36.

A tapered locking hole 37 into which the pin 33 can be fitted is formed on a surface of the cam gear 18 facing the front end of the lock pin 33 on the front side surface of the variable valve timing mechanism 11. . When the lock pin 33 is fitted into the hole 37, the relative rotation between the internal rotor 14 and the cam gear 18 is restricted. As a result, the camshaft 12 (the internal rotor 14) rotates integrally with the cam gear 18 (the housing 16). FIG. 4 shows a state in which the lock pin 33 is fitted into the locking hole 37.

When the lock pin is fitted into the lock hole 37, the internal rotor 14 and the housing 16 are held in a positional relationship as shown in FIG. That is, the vane 19 is connected to the housing 16.
In the concave portion 21, a position where the rotational phase of the camshaft 12 with respect to the cam gear 18 is the most delayed (hereinafter, the relative position of the internal rotor 14 with respect to the housing 16 in this state is referred to as a “most retarded position”). )
Placed in

FIG. 6 shows a state in which the rotation phase moves from the most retarded position to the advanced direction (hereinafter, the inner rotor 14 with respect to the housing 16 in this state).
Is referred to as the “advanced position”).

The variable valve timing mechanism 11 is at the most retarded position when the engine is stopped, and the internal rotor 14 and the cam gear 18 are controlled by the lock mechanism.
Is limited. At this time, the lock pin 33 is fitted in the locking hole 37 as shown in the side sectional view of FIG.

When the engine starts, the oil pump 31 rotates the OCV2 by the rotation of the crankshaft.
7 is supplied with hydraulic pressure. The supplied oil pressure is the same as the OCV
The pressure is sent to the hydraulic passage P1 by 27, whereby the hydraulic pressure in the advance pressure chamber 29 is increased. At this time, the hydraulic pressure is also supplied to the pressure chamber 34 provided in the through hole 32 at the same time. When the oil pressure in the pressure chamber 34 increases to a predetermined value or more, the lock pin 33 moves toward the front cover 22 against the urging force of the spring 36. When the lock pin 33 is disengaged from the inside of the locking hole 37 by this movement, the restriction on the relative rotation between the internal rotor 14 and the cam gear 18 is released, and the variable valve timing mechanism 11 recovers its original function. .

On the other hand, the variable valve timing mechanism 1
As shown in FIG. 4, one camshaft 12 has a two-stage tip, and has a rotating shaft center of the internal rotor 14 and the like as a first rotating body and a rotating shaft of the housing 16 and the like as a second rotating body. The centers are adjusted so that they are coaxial with each other by being assembled to the camshaft 12.

Incidentally, the positional relationship between the lock pin 33 and the locking hole 37 may be slightly shifted due to a processing error of the constituent members or the like. As described above, the tip of the lock pin 33 and the locking hole 37 are tapered so that they can be smoothly inserted. 33 is inserted into the locking hole 37. However, when there is no position error as shown in FIG.
In the case where there is a position error as compared to (a)) (FIG. 7 (b)), the fitting depth of the lock pin 33 is smaller. As described above, even if the fitting depth of the lock pin 33 is somewhat shallow,
There is no problem in performing the function as the lock mechanism.

On the other hand, in such a variable valve timing mechanism 11, as shown in FIG.
The sliding portions A and B between the housing 4 and the housing 16 are provided with a clearance that does not impair the oil sealing property so that the relative rotation can be smoothly performed. Accordingly, when the mechanism 11 is removed from the camshaft 12, the rotation axes of the first rotating body and the second rotating body are not regulated, and the internal rotor 14 is loosely fitted in the housing 16. .

In the above-mentioned inspection and repair, the variable valve timing mechanism 11 is connected to the camshaft 1.
The operation of removing from the engine 2 is performed when the engine is stopped. When the engine is stopped, as described above, the variable valve timing mechanism 11 is in a state where the lock pin 33 is fitted in the locking hole 37, and the movement of the internal rotor 14 is actually restricted. However, at this time, as shown in FIG. 7B, the lock pin 33 and the locking hole 37 are used.
In the case where there is a position error, the following serious problem occurs.

That is, when the variable valve timing mechanism 11 in such a locked state is removed from the camshaft 12, the rotation axis of the internal rotor 14 is not restricted with respect to the rotation axes of the housing 16 and the cam gear 18, so that the same internal The rotor 14 is loosely fitted in the housing 16. At this time, the lock pin 33 is moved by the urging force of the spring 36 into the locking hole 37.
Try to fit deeper into the interior. Therefore, the internal rotor 14 slightly moves within the housing 16 so that the positions of the lock pin 33 and the locking hole 37 match. When the internal rotor 14 moves as described above, the rotation axis of the rotor 14 is shifted with respect to the rotation axis of the housing 16 (cam gear 18). The internal rotor 14 or the housing 16 (cam gear 18) may be attached in an inclined state, or the lock pin 33 may be fixed in the lock hole 37 so that the hydraulic pressure cannot release the lock. Become.

Therefore, in this embodiment, FIGS.
Based on the variable valve timing mechanism 11 shown in FIG.
The improvement is intended in the mode shown in FIGS. In the following, the configuration will be described focusing on the improvements according to the present embodiment.

FIG. 1 is a side sectional view of the variable valve timing mechanism 11 according to the present embodiment, and FIGS. 2 and 3 are front sectional views of the same. As shown in these figures, in the variable valve timing mechanism 11 according to the present embodiment, an insertion hole 38 is formed in the front cover 22, and a screw hole 39 is formed in the internal rotor 14. . These insertion holes 38 and screw holes 39
Are provided at positions where they overlap and communicate with each other at the most retarded position where the lock mechanism operates. Also,
The screw holes 39 formed in the internal rotor 14 are used to reduce oil leakage from the pressure chambers 29 and 30 as shown in FIG.
As shown in FIG. 3, the inner rotor 14 is provided within an angle range where the vanes 19 protrude.

When removing the variable valve timing mechanism 11 from the camshaft 12, as shown in FIGS. 1 and 2, a bolt 40 is previously screwed into a screw hole 39 through the insertion hole 38, and The internal rotor 14 and the front cover 22 are fastened. The front cover 22 is integrated with the housing 16 and the cam gear 18 by being fixed to the mounting bolt 17.
Therefore, even if the mechanism 11 is detached from the camshaft 12 in a state where the mechanism 11 is fastened by the bolts 40, the internal rotor 14 remains in the housing 16 (cam gear 18).
Are maintained in a state where the rotation axis is positioned on the same axis. That is, even if the lock pin 33 and the locking hole 37 are displaced in the manner shown in FIG. 7B, the locking hole 37 is removed by removing the mechanism 11 from the camshaft 12. Of the lock pin 33 does not change.

Further, the variable valve timing mechanism 1
At the time of reassembly to the camshaft 14, the function as the variable valve timing mechanism 11 can be re-allowed by removing the bolt 40 after the reassembly operation. In addition, at this time, since the variable valve timing mechanism 11 can be reattached to the camshaft 12 in almost the same state as before the removal, the stable operation of the mechanism 11 including the lock mechanism is guaranteed. Also. FIG. 3 shows the relationship between the internal rotor 14 and the housing 16 when the lock pin 33 is released with the operation of the engine after the reassembly and the variable valve timing mechanism 11 is operating in the advance direction, and 3 shows a relationship between an insertion hole 38 and a screw hole 39 that constitute a fastening mechanism.

The fastening mechanism according to the present embodiment has a very simple structure in which an insertion hole 38 and a screw hole 39 are provided in the front cover 22 and the internal rotor 14, respectively, and the bolt 40 for fastening is prepared. Due to the structure, adoption to an existing variable valve timing mechanism can be performed very easily.

The effects obtained by the embodiment described above will be described below. -Even when the variable valve timing mechanism 11 is removed from the camshaft 12 and reassembled on the same shaft 12, the rotation axes of the internal rotor 14 and the housing 16 are preferably maintained at the same axis. As a result, the work can be performed easily and accurately.

By performing the work accurately, a stable operation as the variable valve timing mechanism 11 is guaranteed. -After the re-assembly operation, the fastening state can be released by an extremely simple operation of simply removing the fastening bolt 40.

Since the fastening means is constituted by a very simple structure of the insertion hole 38, the screw hole 39 and the fastening bolt 40, the adoption to an existing variable valve timing mechanism is extremely easy.

Since the engaged state is not inadvertently released, it is possible to easily carry the variable valve timing mechanism alone. Note that the present embodiment can be modified as follows, for example.

The insertion hole 38 in this embodiment may be a screw hole, and the screw hole 39 may be changed to an insertion hole. Also,
Both the hole 38 and the hole 39 may be screw holes, and the bolt 40 may be fastened to both the front cover 16 and the internal rotor 14 by screwing.

The position where the fastening mechanism is provided is the position of the internal rotor 1
Any position may be provided as long as the position 4 and the housing 16 can be fixed. For example, an insertion hole is formed on the cam gear 18 side, and a screw hole is formed on a surface of the internal rotor 14 facing the cam gear 18 so that the variable valve timing mechanism 1
The internal rotor 14 and the housing 16 may be fastened to the housing 16 with appropriate bolts from the back of the first rotor 1.

The fastening mechanism may be provided at a plurality of places if necessary. In the variable valve timing mechanism of the present embodiment, the internal rotor 14 and the camshaft 12 rotate integrally, and the housing 16 and the cam gear 18 rotate integrally, but the internal rotor 14 and the cam gear 18 integrally rotate. The housing 16 and the camshaft 12 may rotate so as to rotate integrally.

[0056]

According to the first aspect of the present invention, the first and second rotating bodies can be fastened to a specific rotation phase locked by the lock mechanism through the fastening means. By fastening the first and second rotating bodies in this manner, the lock mechanism is further biased when the rotating body is removed from the camshaft for repair, inspection, or the like. As a result, it is possible to preferably prevent the rotation axes of the first and second rotating bodies from being displaced from each other, so that the operation of reassembling the camshaft can be reliably performed. In addition, since the reassembly operation to the camshaft is performed reliably, stable operation as the variable valve timing mechanism is also ensured. The fastening state of the above-mentioned fastening means is arbitrarily released after the operation of attaching the first and second rotating bodies to the camshaft is completed.

According to the second aspect of the present invention, the first and second rotating bodies can be easily and accurately fastened through a very simple structure in which a bolt is screwed into the communication hole. Will be able to Further, the above-mentioned fastening state can be released by a simple operation of simply removing the bolt from the communication hole. Further, according to the configuration,
Since the fastening state is not inadvertently released, the fastening state can be suitably maintained even when the variable valve timing mechanism alone is conveyed. And in the case of the same configuration,
It can be easily applied to an existing variable valve timing mechanism.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a variable valve timing mechanism according to an embodiment.

FIG. 2 is a front sectional view of the variable valve timing mechanism according to the embodiment;

FIG. 3 is a front sectional view of the variable valve timing mechanism according to the embodiment;

FIG. 4 is a side sectional view showing a basic configuration of a variable valve timing mechanism.

FIG. 5 is a front sectional view showing a basic configuration of a variable valve timing mechanism.

FIG. 6 is a front sectional view showing a basic configuration of a variable valve timing mechanism.

FIG. 7 is a sectional view showing a fitted state of a lock pin.

[Explanation of symbols]

11: Variable valve timing mechanism, 12: Cam shaft, 14: Internal rotor, 16: Housing, 18: Cam gear or sprocket, 22: Front cover, 29 ...
Advance side pressure chamber, 30 ... retard side pressure chamber, 33 ... lock pin, 37 ... locking hole, 38 ... insertion hole, 39 ... screw hole, 40
... Bolts for fastening.

Claims (2)

[Claims] A first and a second rotating body connected to one and the other of a camshaft that opens and closes an output shaft of an internal combustion engine and a valve of the engine having the same rotation axis; First and second liquid chambers are formed on both sides of the vane by dividing the recess formed in the second rotating body with the vane formed in the first rotating body, and A variable valve timing mechanism for an internal combustion engine that changes the relative rotation phase of the engine output shaft and the camshaft by relatively rotating the first and second rotating bodies based on hydraulic pressure control; A lock mechanism for locking the first and second rotating bodies in a specific rotation phase based on the hydraulic pressure supplied to at least one of the first and second liquid chambers; The lock machine Optionally releasably said first and variable valve timing mechanism for an internal combustion engine, characterized in that it comprises a fastening means for fastening the second rotary member, the at locked the particular rotational phase by. 2. The method according to claim 1, wherein the fastening unit is configured to lock the first and the second in a specific rotation phase locked by the lock mechanism.
And a communication hole formed by communicating a screw between at least one of the first and second rotating bodies and having a screw formed in an inner periphery of the first and second rotating bodies, and a bolt screwed into the communicating hole. 2. The variable valve timing mechanism for an internal combustion engine according to claim 1.