JP3265899B2 - Valve timing control device for internal combustion engine - 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 for controlling the opening / closing timing of an intake / exhaust valve according to the operating state of an internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, a valve timing control apparatus for an internal combustion engine of this type has been proposed in Japanese Patent Application Laid-Open No. 6-264705. In the embodiment described in the publication, a cam shaft is rotatably supported by a journal bearing provided on a cylinder head of an engine, and a timing pulley is rotatably provided at one end thereof. A ring gear is interposed between the timing pulley and the camshaft. The ring gear has helical teeth formed on the inner and outer circumferences thereof, and is meshed with the camshaft and the timing pulley by the helical teeth. A retard side hydraulic chamber and an advance side hydraulic chamber are formed at the front end side and the rear end side of the ring gear, respectively.

Further, an advance control passage and a retard control passage for supplying hydraulic oil to the two hydraulic chambers are formed in the camshaft and the cylinder head. The two passages are formed with openings on the journal surface in the journal bearing. The opening of the retard control passage is provided apart from the opening of the advance control passage,
It is formed so as to be located at the corner of the journal surface.

In the prior art valve timing control device having such a configuration, the hydraulic oil pumped from the hydraulic pump is supplied to both hydraulic chambers via an advance control passage or a retard control passage selected by an electromagnetic switching valve. Is supplied to any of The ring gear is urged by the oil pressure in the hydraulic chamber to which the hydraulic oil is supplied, and moves in the camshaft axial direction. Since the timing pulley and the camshaft are meshed with the ring gear and the helical teeth, the movement of the ring gear changes the relative rotational phase between the timing pulley and the camshaft, and as a result, the valve opening / closing timing is changed.

[0005]

In the prior art valve timing control apparatus, the opening of the retard control passage is provided at the corner of the journal surface to increase the distance from the opening of the advance control passage. . This is because the distance (seal length) between the openings of the two oil passages provided on the journal surface is made as large as possible, and the oil pressure in the oil passages is prevented from interfering with each other, thereby enabling the valve timing control in the valve timing control. This is because it is necessary to prevent a decrease in responsiveness.

[0006] However, increasing the distance between the openings of the two passages on the journal surface necessarily increases the journal width, and further increases the camshaft length and the overall engine length. In addition, there is a concern that the weight of the cylinder head will increase as the journal width increases. As described above, in the conventional valve timing control device, in order to ensure the sealing performance of the oil passage provided for valve timing control, to increase the journal width, or conversely, to reduce the journal width, The sealing properties of both oil passages had to be reduced to some extent.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to increase the journal width in a valve timing control device having two oil passages for valve timing control. It is an object of the present invention to improve the sealing performance of both oil passages without doing so.

[0008]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a cam shaft for driving a valve rotatably supported by a journal bearing provided on a cylinder head; A pulley provided at one end of the camshaft so as to be relatively rotatable with respect to the camshaft, teeth provided on an inner circumference are outer teeth of the camshaft, and teeth provided on an outer circumference are inside the pulley. At least one of the teeth provided on the inner and outer circumferences is meshed with the teeth, and at least one of the teeth is a helical tooth, and two hydraulic chambers provided on both front and rear sides of the ring gear in the camshaft axial direction are provided with hydraulic pressure. A first oil passage and a second oil passage for supplying oil from a supply source are provided, and the oil pressure in both the hydraulic chambers is changed to move the ring gear in the camshaft axial direction. And by, in the valve timing control apparatus for an internal combustion engine with variable timing valve opening and closing by changing the relative rotational phase between the camshaft and the pulley, the first thrust bearing portion opposing to the side cylinder head is formed on the camshaft And the first thrust bearing
At the position facing the cylinder head
A second thrust bearing portion is formed, the first oil passage is formed so as to pass through a thrust surface of the first thrust bearing portion, and the second oil passage is the journal bearing other than the first thrust bearing portion. A third oil passage formed so as to pass through the sliding surface of the portion and communicating with the hydraulic pressure source;
An opening for a thrust surface of the second thrust bearing portion;
The main purpose is to be formed .

[0009]

[0010]

According to the first aspect of the present invention, the first oil passage for valve timing control is formed through the thrust surface of the first thrust bearing portion, while the second oil passage for valve timing control is also formed. The oil passage is formed so as to pass through a sliding surface of the journal bearing other than the first thrust bearing. At this time, the oil leaks slightly from the opening on the thrust surface of the first oil passage and the opening on the sliding surface of the second oil passage. However, since the two openings are provided apart from each other, the oil pressure in both oil passages does not interfere.

Further , in addition to the above operation, the thrust generated on the camshaft by the oil pressure in the second oil passage is offset by the reverse thrust generated on the camshaft by the oil pressure in the third passage. Therefore, the sliding resistance on the thrust surfaces of the first and second thrust bearing portions is reduced.

[0012]

【Example】

(First Embodiment) A first embodiment in which the present invention is embodied in an automobile engine will be described below with reference to FIGS.

In this embodiment, an intake valve (not shown)
A valve timing control mechanism (hereinafter, referred to as VVT) 2 is provided at one end of an intake side camshaft (hereinafter, simply referred to as a camshaft) 1 to control the opening / closing timing of the camshaft. The camshaft 1 is rotatably supported by a journal bearing 5 provided between a cylinder head 3 and a bearing cap 4 of the engine. Flanges 7 and 8 are formed on both front and rear sides of the cam journal 6 supported by the journal bearing portion 5 so as to sandwich the cylinder head 3 and the bearing cap 4. The two flanges 7 and 8 regulate movement of the camshaft 1 in the axial direction, and the respective flanges 7 and 8 are in sliding contact with the side surfaces of the cylinder head 3 and the bearing cap 4. Note that the flange 7 provided on the front side of the cam journal 6 constitutes a first thrust bearing portion in the present invention.

At one end of the camshaft 1, a timing pulley 9 is provided as a pulley. The timing pulley 9 includes a pulley body 10 and a cover 11. A timing belt 12 is mounted on the pulley body 10. The pulley body 10 has a substantially disk shape, and is inserted into the camshaft 1 at its boss 13 so as to be relatively rotatable. The cover 11 has a bottomed cylindrical shape, and is attached so as to cover the tip of the camshaft 1. Also,
A communication hole 14 is formed at the bottom of the cover 11, and a lid 15 is detachably attached to the communication hole 14. A flange 16 is formed on the outer periphery of the cover 11, and the cover 11 is fixed to the side surface of the pulley body 10 by a plurality of bolts 17 and pins 18 at the flange 16. An inner cap 19 is attached to the tip of the camshaft 1 and is fixed with a hollow bolt 20.
1 is detented.

An annular space surrounded by the pulley body 10 and the cover 11 is a housing space 22. A ring gear 23 is provided in the housing space 22. Helical teeth 23a and 23b are formed on the inner and outer circumferences of the ring gear 23. Helical teeth 11a as internal teeth are formed on the inner peripheral wall of the cover 11, and helical teeth 19a as external teeth provided on the camshaft 1 side are formed on the outer peripheral surface of the inner cap 19, respectively. The helical teeth 23b provided on the outer periphery of the ring gear 23
The helical teeth 23 a meshed with the first helical teeth 11 a and provided on the inner periphery of the ring gear 23
With the helical teeth 19a.

The housing space 22 is divided by a ring gear 23 into two hydraulic chambers. The hydraulic chamber formed at the distal end of the ring gear 23 is an advanced hydraulic chamber 24, and the hydraulic chamber formed at the proximal end of the ring gear 23 is a retard hydraulic chamber 25. The cylinder head 3 is provided with an advance-side head oil passage 26 and a retard-side head oil passage 27 for supplying lubricating oil to the two hydraulic chambers 24 and 25. A journal groove 28 extending in the circumferential direction is formed in the cam journal 6, and the advance side head oil passage 26 is opened in the journal groove 28.

The thrust surface of the flange 7 provided on the tip side of the cam journal 6 (right side in FIG. 1 or 2)
Is formed with a flange groove 29 extending in the circumferential direction.
The downstream side (the upper side in FIGS. 1 and 2) of the retard side head oil passage 27 is directed toward the flange groove 29 and is opened to the flange groove 29.

In the camshaft 1, an advance shaft oil passage 30 and a retard shaft oil passage 31 extending in the axial direction are formed substantially in parallel. A communication hole 32 is formed in the boss 13 of the pulley body 10, and a circumferential groove 33 extending in the circumferential direction is formed on the outer peripheral surface of the camshaft 1 at a position corresponding to the communication hole 32. The retard side shaft oil passage 31
Is communicated with the retard-side hydraulic chamber 25 via the circumferential groove 33 and the communication hole 32 at a position near the front end. The base end side of the retard shaft oil passage 31 faces the flange groove 29 and communicates with the flange groove 29. The tip end of the retard shaft oil passage 31 is closed by the inner cap 19.

On the other hand, the leading end side of the advance-side shaft oil passage 30 is connected to the advance-side hydraulic chamber 2 through the center hole 20a of the hollow bolt 20.
It is communicated with 4. The base end of the advance shaft oil passage 30 is directed toward the journal groove 28 and communicates with the advance head oil passage 26 via the journal groove 28.

The retard control oil passage A is constituted by the retard head oil passage 27, the flange groove 29, the retard shaft oil passage 31, the circumferential groove 33, and the communication hole 32. A constitutes a first oil passage of the present invention. On the other hand, the advance angle control oil passage B is formed by the advance angle head oil passage 26, the journal groove 28, the advance angle shaft oil passage 30, and the center hole 20a of the hollow bolt 20, and the advance angle control oil passage B Constitutes a second oil passage of the present invention.

As shown in FIG. 1, the upstream side (the lower side in FIGS. 1 and 2) of the advance side and retard side head oil passages 26, 27 is an oil control valve 34, an oil filter 35, and an oil as a hydraulic pressure source. It is connected to an oil pan 38 via a pump 36 and an oil strainer 37. The hydraulic oil (lubricating oil) that has passed through the oil strainer 37 from the oil pan 38 is discharged from the oil pump 36,
The oil is supplied to the advance side or retard side hydraulic chambers 24 and 25 via one of the two head oil passages 26 and 27 selected by the oil control valve 34.

In this embodiment, when the engine is running and the crankshaft (not shown) is rotated, the rotational driving force is transmitted to the timing pulley 9 provided on the camshaft 1. Then, the rotational driving force is transmitted from the timing pulley 9 to the camshaft 1 via the ring gear 23, and the intake valve (not shown) is opened and closed. At this time, the opening and closing timing of the intake valve is controlled by the VVT 2 according to the operating state of the engine.
Hereinafter, the control of the opening / closing timing of the intake valve by the VVT 2 will be described.

When the opening / closing timing of the intake valve is changed to the advance side, the hydraulic oil discharged from the oil pump 36 is pumped to the advance side head oil passage 26 by the oil control valve 34. The hydraulic oil in the advance head oil passage 26 is introduced into the advance hydraulic chamber 24 through the journal groove 28, the advance shaft oil passage 30, and the center hole 20 a of the hollow bolt 20. Accordingly, the hydraulic pressure in the advance hydraulic chamber 24 increases, and the ring gear 23 is urged by the hydraulic pressure to move to the base end side of the camshaft 1. At this time, the lubricating oil in the retard-side hydraulic chamber 25 is returned to the retard-side head oil passage 27 via the communication hole 32, the circumferential groove 33, the retard-side shaft oil passage 31 and the flange groove 29. The head oil passage 27 is opened to an oil pan 38 via an oil control valve 34.

The inner cap 19 fixed to the camshaft 1 and the cover 11 of the timing pulley 9 are composed of a ring gear 23 and helical teeth 19a, 23a, 11a, 23.
b, the relative positions of the two 1 and 9 in the rotation direction change with the movement of the ring gear 23. As a result, the opening / closing timing of the intake valve is changed to the advance side.

On the other hand, when changing the opening / closing timing of the intake valve to the retard side, the hydraulic oil discharged from the oil pump 36 is pumped to the retard head oil passage 27 side by the oil control valve 34. The hydraulic oil in the retard head oil passage 27 is introduced into the retard hydraulic chamber 25 through the flange groove 29, the retard shaft oil passage 31, the circumferential groove 33, and the communication hole 32. Therefore, the oil pressure in the retard hydraulic chamber 25 increases, and the ring gear 23 is urged by the oil pressure to move to the tip end side of the camshaft 1. At this time, the lubricating oil in the advance side hydraulic chamber 24 is returned to the advance side head oil passage 26 via the center hole 20a of the hollow bolt 20, the advance side shaft oil passage 30, and the journal groove 28. An oil pan 38 from the head oil passage 26 through an oil control valve 34
Open to the public. The relative positions of the camshaft 1 and the timing pulley 9 in the rotation direction are determined by the ring gear 23.
And the opening / closing timing of the intake valve is changed to the retard side.

As described above, in this embodiment, VVT2
Thus, the opening / closing timing of the intake valve is controlled to be advanced or retarded. Next, the operation of the present embodiment having the above configuration will be described.

The retard control oil passage A (retard head oil passage 27,
Flange groove 29, retard shaft oil passage 31, circumferential groove 33,
The communication hole 32 is formed so as to pass through the thrust surface of the flange 7. On the other hand, the advance control oil passage B (formed of the advance head oil passage 26, the journal groove 28, the advance shaft oil passage 30, and the center hole 20a) passes through the journal surface of the journal bearing portion 5. It is formed so that. Therefore, the retard control oil passage A has an opening on the thrust surface, and the advance control oil passage B has an opening on the journal surface. The hydraulic oil in both oil passages A and B leaks slightly from both openings,
In this embodiment, the two oil passages A and B are arranged so as to pass through the thrust surface of the flange 7 and the journal surface of the journal bearing portion 5, respectively. The sealability of the opening is improved. More specifically, the hydraulic oil leaked from one oil passage does not flow into the other oil passage, and there is no possibility that the oil pressures of both oil passages A and B interfere with each other. Therefore, stable valve timing control can be performed.
Further, in this embodiment, since the oil passage formed to pass through the journal surface is only the advance control oil passage B, the journal width can be equal to or smaller than that of the conventional art. By reducing the journal width, the length of the camshaft 1 and thus the overall length of the engine can be reduced. In addition, the length of the journal bearing portion 5 provided on the cylinder head 3 that supports the cam journal 6 can be shortened, and the cylinder head 3 can be reduced in size.
Weight can be reduced.

Next, an embodiment other than the first embodiment will be described. In the following embodiments, the basic configuration and operation of the VVT 2 are the same as those of the first embodiment, and only the configuration near the journal bearing 5 and the flanges 7 and 8 is different from that of the first embodiment. Therefore, the same reference numerals are given to the same or corresponding components as in the first embodiment, and description thereof is omitted.

(Second Embodiment) A second embodiment of the present invention will be described with reference to FIG. In the second embodiment, a journal lubrication oil passage C is provided in addition to the retard control oil passage A and the advance control oil passage B for valve timing control. The journal lubrication oil passage C is the lubrication head oil passage 3
9, a journal groove 40, a pair of oil holes 41, and a lubricating shaft oil passage 42. The lubrication head oil passage 39 is provided in the cylinder head 3 and communicates with the journal groove 40. The journal groove 40 is formed at a corner of the cam journal 6. The upstream side (the lower side in FIG. 3) of the lubrication head oil passage 39 is connected to the hydraulic pump 35. An advance-side shaft oil passage 30 is formed inside the camshaft 1, and the advance-side shaft oil passage 30 is formed with an oil hole 30 formed in the radial direction of the camshaft 1.
a communicates with the journal groove 28. Also,
The advance side shaft oil passage 30 has a base end side extending therefrom,
The extended portion forms a lubricating shaft oil passage 42. A seal member 48 is provided between the advancing shaft oil passage 30 and the lubricating shaft oil passage 42, and the seal member 48 circulates hydraulic oil (lubricating oil) between the oil passages 30 and 42. Regulated. The lubricating shaft oil passage 42 communicates with the journal groove 40 through a pair of oil holes 41.

In the second embodiment having the above configuration, the journal lubricating oil passage C is used to form the journal bearing portion 5 shown in FIG. Lubricating oil is supplied to a journal bearing (not shown). In the case where the oil passages A and B for valve timing control are formed so as to pass through the journal surface as in the related art, adding the journal lubrication oil passage C to the journal surface increases the journal width. It will expand. Therefore, in order to avoid this, the width of another cam journal on the base end side of the camshaft 1 must be increased to form the journal lubricating oil passage C. However, such a configuration may complicate the oil passage. On the other hand, in this embodiment, the retard control oil passage A is formed so as to pass through the thrust surface of the flange as in the first embodiment. The path C can be formed.

(Third Embodiment) Next, a third embodiment will be described with reference to FIG. 4, focusing on differences from the second embodiment.

In this embodiment, the opening positions of the advancing control oil passage B and the journal lubrication oil passage C in the journal bearing portion 5 are arranged in a reverse manner to the second embodiment. That is, the journal groove 40 forming a part of the journal lubrication oil passage C is formed at a substantially central position in the axial direction of the cam journal 6. And the head oil passage 3 for lubrication
9 is the journal groove 40 in the cylinder head 3.
It is formed so that it may open to. Further, the journal groove 40 is connected to the lubricating shaft oil passage 4 through the oil hole 41.
It is communicated with 2.

On the other hand, the journal groove 28 forming a part of the advance control oil passage B is located at the position where the journal groove 40 for lubricating the journal is formed in the second embodiment, that is, the cam journal 6. Are formed at the corners. The journal groove 28 communicates with the advance-side head oil passage 26 formed in the cylinder head 3 and communicates with the advance-side shaft oil passage 30 via an oil hole 30a.

In the third embodiment having the above configuration, the journal lubricating oil passage C can be formed without increasing the journal width, as in the second embodiment. Further, the journal groove 40 of the journal lubricating oil passage C is formed substantially at the center of the cam journal 6. Therefore,
In this embodiment, the working oil (lubricating oil) is easily supplied over the entire journal surface, and the lubrication state of the journal surface can be maintained in a good state.

(Fourth Embodiment) Next, a fourth embodiment will be described with reference to FIGS. 5 (a) and 5 (b). FIG. 5 (a)
And (b) shows that a camshaft 1 having two flanges 7, 8 has a cylinder head 3 at its cam journal 6.
2 and a state in which it is supported by the bearing cap 4. The bottom surface of the bearing cap 4 is formed with an oil groove 43 having a semicircular cross section and a substantially L-shape. When the bearing cap 4 is attached to the cylinder head 3 by the bolt 44, a space is formed between the oil groove 43 and the upper end surface of the cylinder head 3, and the working oil can flow in the space. The retard side head oil passage 27 provided in the cylinder head 3 is
Side, and is opened to the oil groove 43 formed in the bearing cap 4. One end of the oil groove 43 is open to a flange groove 29 formed in the flange 7. Therefore, when the opening / closing timing of the intake valve is changed to the retard side, the hydraulic oil is supplied as shown in FIG.
As shown by the arrow in FIG. 5B, the retard side head oil passage 27
Through the oil groove 43 and the flange groove 29 to the retard-side shaft oil passage 31 (not shown in FIG. 5), and is supplied to the retard-side hydraulic chamber 25. On the other hand, the advance side hydraulic chamber 24
Hydraulic oil flows through the advance-side head oil passage 26 in the direction indicated by the arrow, and is returned to the oil pan 38. Further, when changing the opening / closing timing of the intake valve to the advanced side, the hydraulic oil flows in a direction opposite to the direction shown in FIG.

In the fourth embodiment having the above structure, the oil groove 43 is formed on the bottom surface of the bearing cap 4 and the space formed by the oil groove 43 and the upper end surface of the cylinder head 3 is used to control the retard control oil. It is part of Road A. Therefore, the processing of the retard head oil passage 27 in the cylinder head 3 can be simplified.

(Fifth Embodiment) Next, a fifth embodiment will be described with reference to FIGS. 6 (a) and 6 (b). Since the basic configuration of the fifth embodiment is the same as that of the fourth embodiment, the description will focus on the differences. FIG. 6A,
In (b), the same components as those in the fourth embodiment are denoted by the same reference numerals as in FIGS. 5 (a) and 5 (b).

As shown in FIG. 6B, the retard head oil passage 27 formed in the cylinder head 3 is communicated with an oil groove 43 formed in the bearing cap 4. Further, as shown in FIG. 6A, the oil groove 43 has a substantially T-shape with another oil groove 45 connected thereto. The oil groove 45 extends toward the flange 8 formed on the base end side of the journal 6. The flange 8 is formed with a flange groove 46 extending in the circumferential direction similarly to the flange 7, and the oil groove 45 is formed in the flange groove 46.
It is open to. With this configuration, the oil pressure in the retard control oil passage A is introduced into the respective flange grooves 28 and 46 formed in the flanges 7 and 8.
The flange 8 formed on the base end side of the cam journal 6 constitutes a second thrust bearing of the present invention,
The third oil passage of the present invention is constituted by the oil groove 45 extending toward the flange 8.

In the fifth embodiment having the above configuration, the oil pressure in the retard control oil passage A acts on both flanges 7 and 8 formed on the camshaft 1. Here, the thrust force generated on both flanges 7 and 8 by the hydraulic pressure acts in the opposite directions, so that the thrust force is canceled. As a result, the sliding resistance on the thrust surfaces of the flanges 7 and 8 is reduced, and even when the hydraulic pressure of the retard control oil passage A increases, the sliding resistance on the thrust surfaces of the flanges 7 and 8 increases. There is no possibility of causing troubles such as burn-in caused by the trouble.

(Sixth Embodiment) Next, a sixth embodiment will be described with reference to FIG. In the sixth embodiment, flange grooves 29 and 46 are formed in both flanges 7 and 8 provided on the camshaft 1 similarly to the fifth embodiment. The flange grooves 29 and 46 are provided so as to face near both corners of the cylinder head 3. Cylinder head 3
The retard head oil passage 27 provided therein is open to a flange groove 29 formed in the flange 7.
Further, the retard side head oil passage 27 is provided with a communication passage 47 in the middle thereof.
Branch into a substantially Y-shape. And the same connecting passage 4
7 is open to a flange groove 46 formed in the flange 8. The flange 8 provided on the base end side of the cam journal 6 constitutes a second thrust bearing portion of the present invention, and the communication passage 47 opened in the flange groove 46 of the flange 8 constitutes a third oil passage. ing.

In the sixth embodiment having the above configuration, the hydraulic pressure of the retard control oil passage A acts on both flanges 7 and 8 formed on the camshaft 1 as in the fourth embodiment. The sliding resistance on the thrust surfaces of both flanges 7, 8 is reduced. Further, since the retard side head oil passage 27 and the communication passage 47 are opened at a position near the axis of the camshaft, the seal lengths L ₁ and L ₂ on the thrust surface are provided.
Can be increased.

The first to sixth embodiments have been described above.
The present invention can be embodied by changing the configuration of the above embodiment as follows. (1) In the first to sixth embodiments, a flange 7 constituting a first thrust bearing portion is provided on the tip end side of the cam journal 6, and hydraulic oil from a retard side head oil passage 27 is supplied to the flange 7.
Is supplied to the retard-side shaft oil passage 31 through the flange groove 29 described above, but this configuration is changed as follows. The side surface on the base end side of the timing pulley 9 is slid in contact with the side surface of the cylinder head 3, and a circumferential groove extending in the circumferential direction is formed on the thrust surface of the slidably contacted timing pulley 9. Then, the retard side head oil passage 27 is opened to the same circumferential groove. Further, an oil groove extending in the circumferential direction is formed in the camshaft 1, and the oil groove is communicated with the peripheral groove and the oil groove, and the oil groove is communicated with the retard-side shaft oil passage 31.

(2) In the above embodiment, the VVT 2 is provided on the intake camshaft 1 for driving the intake valve to open and close. However, the VVT 2 is provided on the exhaust camshaft for driving the exhaust valve to open and close. The opening / closing timing may be controlled.

(3) The ring gear 23 is the inner cap 1
Although both the cover 9 and the cover 11 are meshed with the helical teeth 23a and 23b, this may be changed to a configuration in which only one of them is meshed with the helical teeth.

(4) In the second embodiment, the journal groove 28 communicated with the advance side head oil passage 26 has one oil hole 3
0a, the oil passage 30 communicates with the advance shaft oil passage 30;
Another oil hole may be provided on the opposite side of 0 degrees, and the journal groove 28 and the advance shaft oil passage 30 may be communicated by a pair of oil holes.

(5) In the above embodiment, the advance control oil passage B
Is formed in the cam journal 6 of the camshaft 1, but may be provided in the cylinder head 3 and the bearing cap 4.

(6) In the fourth to sixth embodiments, the oil groove 45 as the third oil passage having an opening in the flange 8 and the communication passage 47 are both connected to the retard control oil passage A. The oil groove 45 and the communication passage 47 may be configured to communicate with the advance control oil passage B or another hydraulic passage connected to a hydraulic pump.

Hereinafter, other technical ideas which are not described in the claims but are grasped from the above-described embodiments will be described together with their effects. (A) In the valve timing control device for an internal combustion engine according to claim 1, a part of the first oil passage is formed by making an upper end surface of the cylinder head and a bottom surface of the bearing cap face each other. A valve timing control device for an internal combustion engine.

(B) In the valve timing control device for an internal combustion engine according to claim 1 , the first oil passage and the third oil passage
A valve timing control device for an internal combustion engine, wherein a part of a passage is formed by making an upper end surface of a cylinder head and a bottom surface of a bearing cap 4 face each other.

In the valve timing control device for an internal combustion engine described in the above (a) and (b), the processing of the first oil passage or the third oil passage can be simplified.

[0051]

According to the first aspect of the present invention, in a valve timing control device having two oil passages for valve timing control, the sealing performance of both oil passages can be improved without increasing the journal width. Can be planned.

Further , in addition to the above effects, the first and second
The thrust force generated in the thrust bearing portion can be offset, and the sliding resistance in both thrust bearing portions can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a valve timing control mechanism according to a first embodiment.

FIG. 2 is an enlarged sectional view showing the vicinity of a cam journal.

FIG. 3 is an enlarged sectional view showing the vicinity of a cam journal according to a second embodiment.

FIG. 4 is an enlarged sectional view showing the vicinity of a cam journal in a third embodiment.

FIG. 5 is an enlarged view of a camshaft, a cylinder head, and a bearing cap according to a fourth embodiment, and shows an arrangement state of an advance control oil passage and a retard control oil passage;
(A) is a partial plan view, (b) a partial front view.

FIG. 6 is an enlarged view showing a camshaft, a cylinder head, and a bearing cap of a fifth embodiment, and also shows an arrangement state of an advance control oil passage and a retard control oil passage;
(A) is a partial plan view, (b) a partial front view.

FIG. 7 is an enlarged sectional view showing the vicinity of a cam journal according to a sixth embodiment.

[Explanation of symbols]

1. Camshaft 2. Valve timing control mechanism 3.
... Cylinder head, 5 ... Journal bearing, 6 ... Cam journal, 7 ... Flange (first thrust bearing), 8 ...
Flange (second thrust bearing portion), 9 timing pulley, 19a helical teeth (helical teeth on camshaft side), 23 ring gears, 23a, 23b helical teeth (helical teeth on ring gear side), 24 advance side Hydraulic chamber (hydraulic chamber), 25: retard side hydraulic chamber (hydraulic chamber), 26: advance head oil passage, 27: retard head oil passage, 28: journal groove, 29: flange groove, 30: advance Corner shaft oil passage, 20a ... oil hole, 31 ... retard shaft oil passage, 32 ...
Communication hole, 33: peripheral groove, 36: oil pump (hydraulic supply source), 43: oil groove, 45: oil groove (third oil passage), 47:
Communication passage (third oil passage), 27, 29, 31, 32, 33
Form a first oil passage, and 20a, 26, 28, 3
The second oil passage is constituted by 0 and 30a.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F01L 1/34 F01L 1/04 F01M 1/06

Claims (1)

(57) [Claims] 1. A journal provided on a cylinder head.
A valve driving valve rotatably supported at the bearing
Shaft and one end of the camshaft relative to the same camshaft.
A pulley rotatably provided, and teeth provided on an inner periphery of which are provided with outer teeth of the camshaft and an outer periphery thereof.
Are respectively meshed with the internal teeth of the pulley.
And at least one of the teeth provided on the inner and outer circumferences.
The ring gear is a helical tooth, and the front and rear sides of the ring gear in the camshaft axial direction
The two hydraulic chambers provided in
A first oil passage for supplying oil; and a second oil passage for supplying oil.
By moving the camshaft in the axial direction of the camshaft,
When opening and closing the valve by changing the relative rotational phase between
Valve timing control device for internal combustion engine with variable period
And the camshaftToThe first switch facing the side of the cylinder head
While the last bearing part is formed,This first thrust
The side of the cylinder head at a position facing the bearing
And a second thrust bearing portion is formed,  The first oil passage passes through the thrust surface of the first thrust bearing.
And the second oil passage is
1Sliding surface of the journal bearing other than the thrust bearing
Is formed to pass through, The third oil passage communicated with the hydraulic pressure supply is provided with the second slurry.
Formed with an opening to the thrust surface of the strike bearing
To Valve timing control apparatus for an internal combustion engine
Place.