JPH04301112A - Lubricating device of engine - Google Patents

Abstract

PURPOSE:To enhance the lubrication performance by constituting it such that high-pressure oil is supplied to a fluid type valve brush mechanism through the first oil passage provided in a cam shaft and to a variable valve timing mechanism through the hollow passage inside the cam shaft from the other end of the first oil passage. CONSTITUTION:In a cylinder head, oil passages 48 and 49 are made, in parallel with cam shafts, in the region between said cam shaft 22 and 23 on the intake side and the exhaust side. Each oil passage 48 and 49 communicate with tappet holes by distribution passages 50 and 51, respectively, and supply oil to each fluid type backlash mechanisms 18 and 19. Moreover, in the cylinder head 3, an oil passage 54 is made in the outside part across the tappet wheel 14 from the oil passage 49. And this oil passage 54 communicates with each bearing through a distribution passage 55, and also communicates with the oil passage 49 through an orifice 56. Moreover, the oil passage 49 communicates with the bearing of a variable valve timing mechanism through a communication passage 60.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine lubricating system that supplies oil to a variable valve timing mechanism and a hydraulic valve lash mechanism through an oil supply passage provided in a cylinder head.

0002

[Prior Art] In engines such as automobiles, for example,
DOHC (Double Overhead Cams)
Haft) type engines are equipped with a camshaft in the cylinder head that opens and closes the intake valves, and a camshaft that opens and closes the exhaust valves, and the rotational force of the crankshaft is applied to one of the pair of camshafts. The rotational force is transmitted via a rotational force transmission means to drive both of the camshafts.

[0003] In such an engine, the camshaft to which the driving force of the crankshaft is transmitted is equipped with a
There is one equipped with a variable valve timing mechanism as disclosed in Japanese Patent No. 57711. In the variable valve timing mechanism, a cam pulley is attached to the camshaft so that it can rotate by a predetermined angle, and the valve timing is changed by changing the phase of the camshaft.

[0004] By being equipped with such a variable valve timing mechanism, the above-mentioned engine changes the opening and closing timing of the intake valve depending on the engine speed, thereby improving acceleration performance in both the low speed range and the high speed range. can be improved.

[0005] Furthermore, some DOHC engines are provided with a fluid valve lash mechanism that adjusts the valve gap using hydraulic pressure in the valve operating mechanisms on the intake side and the exhaust side.

[0006] In such an engine, the valve gap, which changes due to thermal expansion, wear, etc. of the valve operating mechanism, can be maintained at 0 mm at all times, thereby preventing deviations in valve opening and closing timing.

[0007]

By the way, in an engine equipped with a variable valve timing mechanism and a hydraulic valve lash mechanism as described above, lubricating oil is supplied to the camshaft bearing in the cylinder head to lubricate it. However, it is also necessary to supply the above-mentioned oil as operating oil to the variable valve timing mechanism and the hydraulic valve lash mechanism. For this reason, high oil pressure is required to ensure responsive and stable operation of the variable valve timing mechanism and hydraulic valve lash mechanism. It is necessary to provide a supply passage.

However, in the above-mentioned conventional configuration, since the spacing between camshafts has become narrower in engines that have become smaller in recent years, a large amount of oil is stored in that space, avoiding intake and exhaust valves, spark plugs, etc. It becomes difficult to provide a supply passage.

In addition, in the conventional configuration described above, it is necessary to supply lubricating oil in addition to operating oil to the variable valve timing mechanism, but if oil is not supplied promptly during cold periods, the variable valve timing mechanism There is a risk of seizure of the journal part of the valve timing mechanism. For this reason, it is necessary to provide the oil supply passage in the shortest route in the cylinder head, but this is also difficult due to the reasons mentioned above.

The present invention has been made in view of the above-mentioned circumstances, and is capable of supplying high-pressure working oil to the hydraulic valve lash mechanism and variable valve timing mechanism, as well as quickly supplying lubricating oil to the variable valve timing mechanism. It is intended to supply.

[0011]

[Means for Solving the Problems] In order to solve the above problems, the present invention is characterized by taking the following measures.

That is, in the engine lubricating device according to claim 1 of the present invention, a pair of camshafts for opening and closing intake and exhaust valves, respectively, are provided in the cylinder head so as to be rotationally driven by the crankshaft. A variable valve timing mechanism for adjusting the opening/closing timing of the intake and exhaust valves is attached to the end of one of the camshafts that is rotationally driven, while a valve gap is provided between both the camshafts and the intake and exhaust valves. In the engine, a hollow passage provided inside the drive camshaft communicates with the variable valve timing mechanism at one end, and an inner side of both the camshafts in the cylinder head. Two first oil passages are provided in parallel with the camshaft for supplying oil sent from the oil pump to the fluid valve lash mechanism, and a first oil passage is provided on the drive camshaft side. One end is connected to the other end of the hollow passage, and the other end is configured to communicate with a lubrication point of the variable valve timing mechanism, and is a connecting part between the first oil passage and the hollow passage. A control valve is provided for connecting both passages and for connecting the hollow passage to the discharge passage.

The engine lubrication device according to claim 2 is the engine lubrication device according to claim 1, which comprises:
A second oil passage for supplying oil to the journal portion of the driving camshaft is provided outside the driving camshaft in the cylinder head in parallel with the driving camshaft, and one end of the second oil passage is connected to the second oil passage. 1 is connected to a different end of the variable valve timing mechanism side of the oil passage.

[0014]

[Operation] In the engine lubrication device according to claim 1,
High-pressure oil sent out from the oil pump is directly supplied to the fluid valve lash mechanism through a first oil passage provided along the camshaft, and is also supplied from the other end of the first oil passage to the hollow inside the drive camshaft. Through the passage, it is directly supplied to the variable valve timing mechanism. Therefore, the hydraulic valve lash mechanism and variable valve timing mechanism are highly responsive due to high hydraulic pressure.
And it can be operated stably. In addition, in the above configuration, since the lubricating oil supply path is formed as the shortest path, lubricating oil can be quickly supplied to the variable valve timing mechanism during cold periods, and seizure can be prevented. Can be done.

On the other hand, in the engine lubricating device according to the second aspect, when the oil reaches the end of the first oil passage that is different from the variable valve timing mechanism side, it passes through the second oil passage connected to the end of the first oil passage to the drive cam. Supplied to the journal section of the shaft. Therefore, a drop in oil pressure in the first oil passage on the drive camshaft side is suppressed, and the oil supplied to the variable valve timing mechanism can be maintained at a high pressure.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 9.

As shown in FIG. 2, the engine 1 is a V type 6 engine.
It is a cylinder DOHC type and includes a cylinder block 2 and cylinder heads 3 and 4, and a part of the cylinder block 2 and the cylinder heads 3 and 4 constitute cylinder banks 5 and 6 each having three cylinders. There is. Furthermore, a crankcase 7 and an oil pan 8 are arranged below the cylinder block 2.

Next, details of the cylinder heads 3 and 4 will be explained. Incidentally, since the cylinder heads 3 and 4 have substantially the same structure, only the cylinder head 3 will be described for convenience.

As shown in FIG. 3, the cylinder head 3 is
A combustion chamber 9 is formed corresponding to each cylinder. An intake port 10 and an exhaust port 11 communicate with this combustion chamber 9, and an intake valve 1 is connected to the communication portion on the intake port 10 side.
2 is installed, and an exhaust valve 13 is installed in the communication section on the exhaust port 11 side. These intake valves 12 and exhaust valves 13 each have a valve stem 12 serving as a drive shaft.
a and 13a to move in the valve opening/closing direction. Further, the cylinder head 3 is formed with cylindrical tappet holes 14 and 15 that accommodate the valve operating mechanisms of the intake valve 12 and the exhaust valve 13, respectively.

Bucket-shaped tappets 16 and 17 are slidably fitted into these tappet holes 14 and 15. The tappets 16 and 17 have built-in hydraulic valve lash mechanisms 18 and 19, and the valve stems 12a and 12a are connected to each other via these hydraulic valve lash mechanisms 18 and 19.
13a. Fluid valve lash mechanism 1
8 and 19 are valve stems 12a and 13, as is well known.
It expands and contracts due to the relationship between the pressing force caused by a and the oil pressure in the high pressure chamber, and generates a biasing force that always maintains the valve gap at 0 mm.

[0021] Also, the cylinder head 3 and the tappet 16.
Spring 20, 21 which expands and contracts in the direction of movement of the valve stems 12a, 13a is interposed between the valve stem 17 and the valve stem 17.
These springs 20 and 21 cause the tappets 16 and 17 to
An upward force is applied to the by this,
The tappets 16 and 17 are adapted to come into pressure contact with cams 24 and 25 of camshafts 22 and 23 disposed directly above them, respectively.

In the valve train constructed as described above, when the camshafts 22 and 23 rotate, the cams 24 and 25 actuate the tappets 16 and 17 and the valve stems 12a and 1.
3a, the intake valve 12 and the exhaust valve 13 reciprocate in the valve opening/closing direction to open and close the intake port 10 and the exhaust port 11, so as to intake and exhaust air into the combustion chamber 9.

FIG. 4 is a plan view of the cylinder head 3, and the cylinder head 3 shown in this figure has the tappet holes 14, 15, ignition plug insertion holes 26, etc. opened therein. The cylinder head 3 also includes bearing portions 27 that support the camshafts 22 and 23, respectively.
, 28... are provided, and these bearing parts 27..., 28...
. . , camshafts 22 and 23 are respectively arranged around the dashed-dotted lines in the figure. The camshafts 22 and 23 are interlocked by meshing with a pair of camshaft gears 31 and 32 provided in gear chambers 29 and 30.

Camshaft gear 32 of cylinder head 3
A variable valve timing mechanism 33 is protrudingly attached nearby, and this variable valve timing mechanism 33
A cam pulley 34 and a camshaft gear 32, which are fitted onto the outside of the camshaft gear 32, are coupled as will be described in detail later. A timing belt 35 is wound around the cam pulley 34, a cam pulley (not shown) provided on the cylinder head 4, and a crank pulley (not shown) coupled to a crankshaft 77 (described later).

In the drive mechanism configured as described above, when the timing belt 35 is driven by the crankshaft 77, the cam pulley 34 and the camshaft gear 3
2 rotates, and the exhaust side camshaft 23 is driven. Further, as the camshaft gear 32 rotates, the camshaft gear 31 rotates, and the intake-side camshaft 22 as a driving camshaft is driven.

Here, the variable valve timing mechanism 3
3 will be explained in detail.

As shown in FIG. 5, the variable valve timing mechanism 33 is fixed integrally and coaxially with the cam pulley 34 by a casing 36 having a cylindrical body. The casing 36 is externally fitted onto the end of the camshaft 23, and is also fitted onto the camshaft gear 32 in the gear chamber 30 through the relationship between splines and keyways.

The camshaft gear 32 also has a nut 3
The camshaft 23 is rotatably supported by a bearing part 38 formed in the cylinder head 3 via a casing 36.

The bearing portion 38 has recessed stepped portions 3 on both sides thereof.
8a and 38b are formed, and the camshaft gear 32
is fitted into the recessed step 38a by the fastening force of the nut 37 and abutted against one side end surface of the bearing section 38, while the convex step 39 provided on the journal section 39 of the casing 36
a is fitted into the recessed step 38b by the fastening force of the nut 37 and is abutted against the other side end surface of the bearing section 38. In this manner, the bearing portion 38 is held between the camshaft gear 32 and the casing 36 from both sides, thereby positioning the camshaft 23 in the thrust direction. Note that the protruding step portion 39a is sealed around it by an oil seal 40.

[0030] Furthermore, the variable valve timing mechanism 33 includes:
A cam pulley 34 is fixed to the cover 41 by bolts 42, and a casing 36 is also fixed to the cover 41. The cover 41 has a cylindrical interior, and a center block 44 is fitted into the cylindrical portion via a ring piston 43. This central block 44 is
It is fixed to the end of the camshaft 23 with a bolt 45, and is engaged with the ring piston 43 through a spiral engagement groove structure. In addition, the ring piston 43
is also engaged with the cover 41 by a similar engagement groove structure.

The bolt 45 has a communication passage 45a in the center.
is formed. The communication passage 45a communicates the hollow passage 23a formed at the center of the camshaft 23 with the inside of the variable valve timing mechanism 33, and allows oil supplied through the hollow passage 23a to flow into the inside of the variable valve timing mechanism 33. It is designed to guide you. Further, inside the variable valve timing mechanism 33, an introduction passage 46 is provided for supplying the oil introduced as described above to one end surface side of the ring piston 43 to apply oil pressure. Furthermore, a spring 47 is interposed between the ring piston 43 and the casing 36 to apply a biasing force in a direction that opposes the above-mentioned hydraulic pressure.

The variable valve timing mechanism 33 configured as described above is pressed rightward in FIG. 5 by the spring 47 when oil is not supplied. When oil is supplied and hydraulic pressure acts on the ring piston 43, the ring piston 43 moves to the left in the figure against the pressing force of the spring 47. At this time, since the ring piston 43 is mutually engaged with the cover 41 and the center block 44 by the spiral engagement groove structure,
When the ring piston 43 moves, the cover 41 and the center block 44 rotate relative to each other. As a result, the camshaft 23 and the cam pulley 34 also rotate relatively, creating a phase difference between the camshaft 23 and the cam pulley 34, and the opening/closing timing of the exhaust valve 13 changes.

Conversely, when the oil is removed from the variable valve timing mechanism 33 to eliminate the hydraulic pressure acting on the ring piston 43, the ring piston 43 moves to its original position by the pressing force of the spring 47, and the opening/closing timing of the exhaust valve 13 is adjusted. is returned to normal.

In this way, the variable valve timing mechanism 3
3 is designed to switch the opening/closing timing of the exhaust valve 13 in two stages depending on the presence or absence of supplied hydraulic pressure. In the engine 1 equipped with the variable valve timing mechanism 33, by performing this switching according to the rotation speed of the engine 1, acceleration performance in the low rotation range and high rotation range of the engine 1 can be improved. .

Incidentally, in the cylinder head 3 (and cylinder head 4) constructed as described above, oil is supplied to each part by the oil supply structure described below.

As shown in FIGS. 3 and 4, the cylinder head 3 has a region between the camshaft 22 on the intake side and the camshaft 23 on the exhaust side. Oil passages 48 and 49 are provided in parallel. Oil passage 48 as a first oil passage
・49 communicates with the tappet holes 14..., 15... through distribution passages 50..., 51..., respectively, and the fluid valve lash mechanisms 18, 1 in the tappet holes 14, 15
9... is designed to supply oil.

The oil passage 48 is connected to the cylinder head 3.
It communicates with the hollow passage 22a inside the camshaft 22 via a communication passage 52 that opens in the bearing portion 27 provided at the end opposite to the side on which the camshaft gear 31 is disposed. The camshaft 22 is provided with through holes 53 for supplying oil from the hollow passage 22a to each bearing section 27 other than the above-mentioned bearing section 27.

Further, an oil passage 54 is provided inside the cylinder head 3 in parallel to the oil passage 49 on the outer side of the oil passage 49 with the tappet hole 14 interposed therebetween. The oil passage 54 as the second oil passage is the distribution passage 5
5... to each bearing portion 28... and communicates with the oil passage 49 via an orifice 56 provided inside the end of the cylinder head 3 on the side opposite to the side where the camshaft gear 32 is disposed. The oil in the oil passage 49 is supplied to each of the bearing parts 28 through the distribution passage 55. Although not shown, oil is directly supplied to the bearing portion 28 near the orifice 56 from an oil passage 49.

A control valve 57, which will be described in detail later, is connected to the oil passage 54 at the end communicating with it via an orifice 56, and this control valve 57 controls the supply passage 58.
Alternatively, oil is supplied to or discharged from the hollow passage 23a inside the camshaft 23 through the discharge passage 59. In addition, the oil passage 54 is
The end on the camshaft gear 32 side passes between the gear chambers 30 and 31 and extends to the vicinity of the variable valve timing mechanism 33, and although not shown, the communication passage 6
0 to the bearing portion 38. As a result, lubricating oil is supplied to the journal portion 39 of the variable valve timing mechanism 33.

Furthermore, the cylinder head 3 is provided with an oil introduction structure for supplying oil under pressure from an oil pump 72, which will be described later, to the oil passages 48 and 49.

[0041] This oil introduction structure is based on the cylinder head 3.
An oil chamber 61 is provided adjacent to the ignition plug insertion hole 26 in the center, and an oil passage 62 is provided from the bottom of the oil chamber 61 to the lower end surface of the cylinder head 3 as shown in FIG.
, and branch passages 63 and 64 communicating between the oil chamber 61 and the oil passages 48 and 49.

The oil chamber 61 is sealed by a cap 65 and communicates with the outside through an air vent hole 65a provided at the center of the cap 65. As shown in FIG. 7, the oil passage 62 is open to the outside of the intake side of the lower end surface of the cylinder head 3, and from there the oil pumped by the oil pump 72 is sent to the oil chamber 61.
On the other hand, the branch passages 63 and 64 distribute the oil in the oil chamber 61 to the oil passages 48 and 49.

In the oil introduction structure configured as described above, the oil flowing in and out of the oil chamber 61 creates a vortex flow, so that the air contained in the oil is appropriately separated. The released air is discharged to the outside through the air vent hole 65a.

Next, details of the control valve 57 will be explained.

As shown in FIGS. 8 and 9, the control valve 57
is equipped with a solenoid 66, and the oil supply to the valve timing mechanism 33 is controlled by turning on the solenoid 66.
・It is controlled in conjunction with OFF. This control valve 5
7 is provided with a valve chamber 67 that communicates with the oil passage 49, and the supply passage 58 and the discharge passage 59 are formed between the valve chamber 67 and the bearing portion 28, and the outside of the control valve 57 is A drain passage 68 for discharging oil is formed so as to open to.

A plunger 69 that is driven by a solenoid 66 is provided in the valve chamber 67 in a protruding manner. The plunger 69 has a valve body 70, and a spring 7 interposed between the valve body 70 and the end of the valve chamber 67.
1 is biased toward the right in FIGS. 8 and 9. The valve body 70 has a hollow portion 70a that opens toward the oil passage 49, and a hole 70b that communicates with the outer wall of the valve body 70 from the hollow portion 70a.

In the control valve 57 configured as described above, when the solenoid 66 is ON, the plunger 69 moves to the left in the figure against the biasing force of the spring 71, as shown in FIG. By moving, the oil that has flowed into the valve chamber 67 from the oil passage 49 is caused to flow into the supply passage 58 from the hollow portion 70a through the hole 70b. In this case, the discharge passage 59 and the drain passage 68 are closed by the valve body 70. As a result, the variable valve timing mechanism 33
Oil is supplied from the oil passage 49 through the hollow passage 23a of the camshaft 23.

Further, the control valve 57 is configured such that the solenoid 66 is
In the FF state, as shown in FIG. 9, the plunger 69 moves rightward in the figure by the biasing force of the spring 71, so that the valve body 70 moves between the supply passage 58 and the valve chamber 67. At the same time, the discharge passage 59 and the drain passage 68 are made to communicate with each other. As a result, the oil that has been supplied to the variable valve timing mechanism 33 is discharged from the hollow passage 23a to the outside through the control valve 57.

Cylinder head 3 configured as described above
(and the cylinder head 4), as shown in FIG. 1, an oil circulation flow path for circulating oil is formed.

In this oil circulation flow path, the oil pan 8 is connected to an oil passage 75 via an oil pump 72, an oil cooler 73, and an oil filter 74. This oil passage 75 communicates with each bearing portion 77a of the crankshaft 77 via a distribution passage 76...
It is connected to oil jets 78 that inject oil into cylinders (not shown).

The oil passage 75 is connected to the oil chamber 61 of the cylinder head 3 via an oil pipe 62, and this oil chamber 61 is connected to the distribution passages 50..., 51... via branch passages 63 and 64, respectively. It is connected to oil passages 48 and 49 having . The oil passage 48 is connected to the hollow passage 22 at one end.
It is connected to a. On the other hand, the oil passage 49 and the hollow passage 2
3a, a control valve 57 is provided at one end, and the oil passage 49 communicates with the bearing part 28 at one end, and connects to the journal part 39 of the variable valve timing mechanism 33 at the other end through a communication passage 60. I understand. Further, the oil passage 49 communicates with an oil passage 54 having distribution passages 55 through a throttle valve (or the orifice) 56.

Note that the circulation passage formed in the cylinder head 4 is similar to the circulation passage formed in the cylinder head 3, and therefore is not shown in the figure for convenience.

In the above configuration, the oil pumped by the oil pump 72 is delivered to each bearing portion 77 of the crankshaft 77 through the oil passage 75 and the distribution passage 76 .
a... and is once sent to the oil chambers 62 of the cylinder heads 3 and 4 through the oil passage 62, and from there is distributed to the oil passages 48 and 49 through branch passages 63 and 64.

The oil flowing through the oil passage 48 on the intake side is supplied as working oil to the hydraulic valve lash mechanism 18 .
a, from which it is supplied as lubricating oil to the bearings 27 of the cylinder heads 3 and 4. As a result, the hydraulic valve lash mechanism 18 operates with the supplied oil, while the bearings 27 and the camshaft 2
Lubrication with the journal portions 22b of No. 2 is performed.

The oil flowing through the oil passage 49 on the exhaust side is supplied to the hydraulic valve lash mechanism 19 as working oil, and is also supplied to the hollow passage 23 through the communication passage 60.
variable valve timing mechanism 33 connected to the other end of a
supplied as lubricating oil. In addition, the oil passage 49
The flow rate of the oil inside is restricted through a throttle valve (or orifice) 56, and the oil is sent into an oil passage 54, and further supplied to the bearing portions 28 of the cylinder heads 3 and 4 through distribution passages 55. Note that the oil in the oil passage 49 is directly supplied to the bearing portion 28 on one end side of the camshaft 23 . As a result, the variable valve timing mechanism 3
3 and the bearing portions 28 and the journal portions 23b of the camshaft 23 are lubricated.

When changing the valve timing, the oil in the oil passage 49 is sent into the hollow passage 23a through the control valve 57 and supplied to the variable valve timing mechanism 33 as working oil. This causes the variable valve timing mechanism 33 to operate, creating a phase difference between the camshaft 23 and the cam pulley 34.
Valve timing different from normal valve timing is set. Conversely, when the valve timing is returned to normal, the oil in the hollow passage 23a is discharged to the oil pan 8 through the control valve 57. As a result, the variable valve timing mechanism 33 stops operating, and normal valve timing is set.

As described above, in the configuration of this embodiment,
Through the oil passages 48 and 49 and the hollow passage 23a,
The hydraulic valve lash mechanism 18 and the hydraulic valve lash mechanism 18 pump the high-pressure oil from the oil pump 72 with almost no drop in pressure.
19 and the variable valve timing mechanism 33 as working oil. Therefore, the hydraulic valve lash mechanisms 18 and 19 and the variable valve timing mechanism 33 can be operated with good responsiveness and stability.

Furthermore, with the above configuration, the oil in the oil passage 49 can be supplied as lubricating oil to the variable valve timing mechanism 33 via the shortest route through the communication passage 60 while maintaining high pressure. Therefore, even in cold conditions, the variable valve timing mechanism 33 can be lubricated early, and seizure can be prevented.

Furthermore, in the above configuration, the camshaft 2
Since the oil for lubrication (3) is introduced from the end of the oil passage 49 that is different from the variable valve timing mechanism 33 side, the pressure drop in the operating oil supplied to the variable valve timing mechanism 33 can be reduced. Can be suppressed.

[0060]

As described above, in the engine lubricating device according to claim 1 of the present invention, a pair of camshafts for opening and closing intake and exhaust valves, respectively, are provided in a cylinder head so as to be rotationally driven by a crankshaft. has been
A variable valve timing mechanism for adjusting the opening/closing timing of the intake and exhaust valves is attached to the end of one of the drive camshafts that is rotationally driven, while a valve is provided between both the camshafts and the intake and exhaust valves. In an engine provided with a hydraulic valve lash mechanism for adjusting clearance, a hollow passage provided inside the drive camshaft communicates with the variable valve timing mechanism at one end, while a hollow passage between the two camshafts in the cylinder head communicates with the variable valve timing mechanism. Inside, there are two first valves that supply oil sent from the oil pump to the fluid valve lash mechanism.
An oil passage is provided parallel to the camshaft, and a first oil passage provided on the driving camshaft side is connected at one end to the other end of the hollow passage, and at the other end is connected to the variable valve timing. A control valve is configured to communicate with a lubrication point of the mechanism, and a control valve is provided at a connection portion between the first oil passage and the hollow passage, and connects both passages and connects the hollow passage to a discharge passage. It is something that exists.

[0061] As a result, the high-pressure oil sent from the oil pump is directly supplied to the fluid-type valve lash mechanism and the variable valve timing mechanism, so even in a downsized engine, the fluid-type valve lash mechanism can be used. Also, the variable valve timing mechanism can be operated with good responsiveness and stably. Moreover, since the lubricating oil supply path is formed through the shortest route, lubricating oil can be quickly supplied to the variable valve timing mechanism when it is cold, which also has the effect of preventing seizure. to play.

The engine lubrication device according to claim 2 is the engine lubrication device according to claim 1, which comprises:
A second oil passage for supplying oil to the journal portion of the driving camshaft is provided outside the driving camshaft in the cylinder head in parallel with the driving camshaft, and one end of the second oil passage is connected to the second oil passage. 1 is connected to the end of the oil passage that is different from the variable valve timing mechanism side, so in addition to the above effect, it is possible to suppress a drop in the oil pressure supplied to the variable valve timing mechanism. .

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an oil circulation flow path in an engine according to an embodiment of the present invention.

FIG. 2 is a front view showing the external appearance of the engine.

FIG. 3 is a longitudinal sectional view including a valve mechanism of the cylinder head in the engine of FIG. 2;

FIG. 4 is a plan view showing the structure of the cylinder head.

FIG. 5 is a cross-sectional view showing the structure of a variable valve timing mechanism provided in the cylinder head.

FIG. 6 is a partially cutaway view showing an oil introduction structure in the cylinder head.

FIG. 7 is a bottom view showing the structure of the cylinder head.

FIG. 8 is a longitudinal cross-sectional view showing the state of the control valve provided in the cylinder head when the control valve is open.

FIG. 9 is a longitudinal cross-sectional view showing the state of the control valve provided in the cylinder head when the control valve is closed.

[Explanation of symbols]

3.4 Cylinder head 12
Intake valve 13
Exhaust valves 18 and 19 Fluid valve lash mechanism 22 Camshaft 23 Camshaft (drive camshaft) 22a and 23a Hollow passage 27 and 28 Bearing section 33 Variable valve timing mechanism 34 Cam pulley 35
Timing belt 48/49
Oil passage (first oil passage) 50, 51
Distribution passage 54 Oil passage (second oil passage) 55 Distribution passage 57
Control valve 60 Communication passage 61 Oil chamber 62 Oil pipes 63 and 64 Branch passage

Claims (2)

[Claims] Claim 1: A pair of camshafts for opening and closing intake and exhaust valves, respectively, are provided in a cylinder head so as to be rotationally driven by a crankshaft, and one of the driving camshafts is rotatably driven by a crankshaft. A variable valve timing mechanism is attached to the end portion of the engine to adjust the opening/closing timing of the intake and exhaust valves, and a fluid valve lash mechanism is provided between the camshafts and the intake and exhaust valves to adjust the valve clearance. A hollow passage provided inside the drive camshaft communicates with the variable valve timing mechanism at one end, while oil delivered from the oil pump is connected to the inside of both camshafts in the cylinder head through the hydraulic valve. Two first oil passages that supply the lash mechanism are provided in parallel with the camshaft, and one end of the first oil passage provided on the drive camshaft side is connected to the other end of the hollow passage. The other end is configured to communicate with a lubrication point of the variable valve timing mechanism, and connects both passages to a connecting part between the first oil passage and the hollow passage, and discharges the hollow passage. An engine lubricating device characterized by being provided with a control valve connected to a passage. 2. A second oil passage for supplying oil to a journal portion of the driving camshaft is provided outside of the driving camshaft in the cylinder head in parallel with the driving camshaft, and the second oil passage is parallel to the driving camshaft. 2. The engine lubricating device according to claim 1, wherein one end is connected to an end of the first oil passage that is different from the variable valve timing mechanism side.