JPH1181943A - Intake and exhaust valve driving control device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively lubricate a part where a support shaft penetrates a support shaft through-hole of a control housing, with a simple structure. SOLUTION: By rotating a control shaft 33 of this device around an axis, a slider 35 which rotatably supports an outer periphery of an eccentric cam 36 is slid in a slider engagement groove 31, while a control housing 18 and a circular disc 17 are oscillated round a support shaft 42. A lubricating oil passage is formed inside the control shaft 33, for introducing lubricating oil to the outer periphery of the eccentric cam 36. The support shaft 42 is arranged in an area perpendicularly below the slider engagement groove 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the opening and closing of an intake valve and an exhaust valve according to the operating state of an internal combustion engine by rotating a cylindrical camshaft arranged on the outer periphery of a drive shaft at an unequal speed relative to the drive shaft. The present invention relates to an intake / exhaust valve drive control device that variably controls a timing and an operation angle, and particularly to an improvement in a lubrication mechanism.

[0002]

2. Description of the Related Art As a device for variably controlling the opening / closing timing and operating angle of an intake valve and an exhaust valve, for example, as described in U.S. Pat. An application of the principle is known.

Referring to FIG. 6, a cylindrical camshaft 101 divided for each cylinder is provided on the outer periphery of a drive shaft 100 which rotates in synchronization with the rotation of the engine. A cam 101a for driving the exhaust valve 102 is provided. The camshaft 101 has a drive shaft 10
Drive shaft 100 via an annular disk 103 into which the
Is transmitted.

The outer periphery of the annular disk 103 is connected to a control housing 10 via a needle bearing (not shown).
The eccentric cam 105a of the control shaft 105 and the eccentric cam 106a of the support shaft 106 are rotatably inserted into the control housing 104. Then, by rotating the control shaft 105 around the axis, the control housing 104 is moved to the support shaft 1.
6, the center 103a of the annular disk 103 is eccentric with respect to the axis of the drive shaft 100. By controlling this amount of eccentricity, a rotational phase difference occurs between the drive shaft 100 and the camshaft 101, and the valve lift characteristics change.

[0005]

For example, a support shaft 1
The insertion portion 107 through which the control housing 104 penetrates the control housing 104 relatively densely is lubricated by lubricating oil or oil mist scattered in the atmosphere of the valve operating chamber 109. However, for example, immediately after the start of the engine or in a low rotation state, much oil mist cannot be expected, and the lubrication of the insertion portion 107 and the like may not be sufficiently performed.

Therefore, it is conceivable to form a lubricating oil passage extending to the insertion portion 107 in the support shaft 106 or the control housing 104, for example, and to introduce the lubricating oil directly into the insertion portion 107. In that case, the structure becomes very complicated.

The present invention has been made in view of the above problems, and has as its object to provide an intake / exhaust valve drive control device for an internal combustion engine that can effectively lubricate each part with a simple structure.

[0008]

According to a first aspect of the present invention, there is provided an intake / exhaust valve drive control apparatus for an internal combustion engine, wherein the drive shaft rotates in synchronization with the rotation of the engine, and the drive shaft is rotatable relative to the outer periphery of the drive shaft. A cylindrical camshaft having a cam for driving an intake / exhaust valve on an outer periphery thereof; an annular disk formed in an annular shape into which the drive shaft is loosely inserted, for transmitting rotational motion of the drive shaft to the camshaft; A plate-shaped control housing that rotatably holds the outer periphery of the disk, a support shaft that rotatably passes through the control housing, and slidably engages with a rectangular engagement groove formed at one end of the control housing. A slider having an eccentric cam whose outer periphery is rotatably supported by the inner periphery of the slider, and by itself rotating around an axis, with a sliding operation of the slider,
A control shaft for swinging the control housing around the support shaft in the direction perpendicular to the axis, and a lubricating oil passage for introducing lubricating oil to the outer periphery of the eccentric cam is formed inside the control shaft, and the support shaft is It is characterized in that it is arranged in a vertically lower region of the engagement groove.

The above-mentioned vertically lower region is a vertically lower region when the internal combustion engine is used. For example, in the case of a vehicle engine, it means a vertically lower region when the vehicle is mounted on a vehicle.

Further, the invention according to claim 2 is characterized in that the engaging groove is inclined with respect to a vertical line when viewed from the axial direction.

According to a third aspect of the present invention, the support shaft is
It is characterized in that it is arranged vertically below the lowermost end of the engagement groove.

According to a fourth aspect of the present invention, an oil passage is formed in the slider from an inner peripheral surface slidingly contacting the outer periphery of the eccentric cam to an outer peripheral surface slidably engaged with the wall surface of the engagement groove. It is characterized by.

The invention according to claim 5 is characterized in that a concave groove extending in the circumferential direction is formed in the inner peripheral surface of the slider so as to communicate with the oil passage.

According to a sixth aspect of the present invention, the slider includes a first slider block engaged with one wall surface of the engagement groove;
It is characterized by being divided into a second slider block which engages with the other wall surface of the engagement groove.

[0015]

According to the first aspect of the present invention, the lubricating oil is directly introduced to the outer periphery of the eccentric cam through the lubricating oil passage inside the control shaft, and the sliding contact portion between the outer periphery of the eccentric cam and the inner periphery of the slider is provided. Forcibly lubricate. The lubricating oil that has lubricated the sliding contact portion in this way overflows from the engagement groove with which the slider engages,
For example, it flows down along the wall of the control housing,
Most of them are supplied to a support shaft arranged in a region vertically below the slider engagement groove, and for example, the support shaft appropriately lubricates a portion where the control housing is inserted.

As described above, the portion where the support shaft passes through the control housing can be effectively lubricated by utilizing the lubricating oil which has lubricated the sliding portion between the eccentric cam outer periphery of the control shaft and the slider inner periphery. . Therefore, the control shaft and the support shaft rotate smoothly, so that the shaft can be effectively prevented from being bitter, abraded, and stuck, and the control response of the valve lift characteristics is improved.

Here, in the present invention, when lubricating the support shaft insertion portion, it is not necessary to separately provide a lubricating oil passage extending to the insertion portion, so that the structure is extremely simplified.

Further, according to the present invention, even if there is some error in the relative position between the control shaft and the support shaft, of the errors, at least the error in the sliding direction of the slider, Is absorbed by sliding. Therefore, rattling of the control shaft and the support shaft due to dimensional errors and the like is suppressed, and the shafts rotate smoothly, thereby improving the control response of the valve lift characteristics.

In addition, since the sliding contact portion between the outer periphery of the eccentric cam of the control shaft and the inner periphery of the slider comes into surface contact, early wear of the sliding contact portion can be effectively prevented.

According to the second aspect of the present invention, since the engaging groove is inclined with respect to the vertical line when viewed from the axial direction, the horizontal width of the vertically lower region of the engaging groove projected downward is reduced. Substantially expand. As a result, the degree of freedom in layout with respect to the support shaft disposed in the vertically lower region is improved.

According to the third aspect of the present invention, since the lubricating oil guided to the engagement groove is naturally collected at the lowermost end of the inclined engagement groove, the support shaft located vertically below the lowermost end is provided. , More lubricating oil can be reached, and the lubricating effect is improved.

According to the fourth aspect of the present invention, the lubricating oil that has lubricated the sliding contact portion between the outer peripheral surface of the eccentric cam and the inner peripheral surface of the slider passes through the oil passage extending from the inner peripheral surface of the slider to the outer peripheral surface, and passes through the oil passage. The side surface and the wall surface of the engaging groove are directly guided to a slide portion where the slide portion slides, forcibly lubricate the slide portion, and most of the lubricating oil is guided to the support shaft, and the control housing of the support shaft is inserted into the control shaft. Lubricate parts.

As described above, the lubricating oil lubricated in this order on the slider insertion portion of the control shaft and the slide portion where the outer surface of the slider and the wall surface of the engagement groove are in sliding contact with each other is used to effect the control housing insertion portion of the support shaft. Can be lubricated. Therefore, the control shaft, the slider, and the support shaft operate smoothly, so that bitterness, abrasion, sticking, and the like due to insufficient lubrication can be effectively prevented, and the control response of the valve lift characteristics is improved.

Further, since the oil passage penetrates from the inner peripheral surface to the outer peripheral surface of the slider, it can be easily processed by using, for example, a drill.

According to the fifth aspect of the present invention, the lubricating oil that lubricates the sliding contact portion between the eccentric cam outer periphery and the slider inner peripheral surface is more effectively provided through the groove formed in the slider inner peripheral surface. Can be led to the oilway.

According to the sixth aspect of the present invention, since the slider is divided into the first and second slider blocks, even if the eccentric cam of the control shaft is smaller in diameter than the other parts, both slider blocks are controlled. The eccentric cam of the shaft can be assembled so as to sandwich the eccentric cam, and the assembly is extremely easy.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an intake / exhaust valve drive control device according to the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show a first embodiment in which an intake / exhaust valve drive control device according to the present invention is applied to a V-type engine which is an internal combustion engine for an automobile. The auxiliary lines X and Y in FIG. 1 indicate a horizontal line and a vertical line, respectively, in a state where the engine is mounted on a vehicle, that is, in a use state.

Above the cylinder head S, a drive shaft 1 continuous over all cylinders is rotatably supported by a support (not shown). The drive shaft 1 has a sprocket (not shown) attached to one end thereof, and is linked with a crankshaft via a timing chain, so that the drive shaft 1 rotates in synchronization with rotation of the engine. Note that the support portion of the drive shaft 1 is processed using a predetermined position of the cylinder head S as a processing reference.

A cylindrical camshaft 11 divided for each cylinder is fitted to the outer periphery of the drive shaft 1 so as to be relatively rotatable, and a first flange portion 1 is attached to an end of each camshaft 11.
2 are provided. Each camshaft 11 has a pair of cams 11a on its outer periphery for driving, for example, an intake valve, and an intermediate journal portion 11b between the pair of cams 11a.
Is rotatably supported between the cam bracket 13 and a semicircular bearing surface recessed in the cam bracket mounting portion 8 having a partition wall shape on the cylinder head side.

A short sleeve 15 is fixed to the drive shaft 1, and a second flange 16 is formed at an end of each sleeve 15 so as to face the first flange 12. I have. An annular disk 17 having an annular shape into which the drive shaft 1 is loosely inserted is interposed between the flange portions 12 and 16. This annular disk 17
The control housing 18 is rotatably fitted and held in a circular opening 18a. Specifically, the control housing 1
A roller bearing 25 in which a large number of needles are arranged is provided on the inner periphery of 8, and the annular disk 17 is held via the roller bearing 25.

Each of the first flange portion 12 and the second flange portion 16 has an engaging groove (not shown) extending along the radial direction.
They are formed at positions 180 ° different from each other. On the other hand, holding holes are formed in the annular disk 17 at positions different from each other by 180 °, and a first pin 23 and a second pin 24 are rotatably fitted to the respective holding holes. These pins 23 and 24 project in opposite directions to each other, and the tip of the first pin 23 is connected to the first flange 12.
And the tip of the second pin 24 is slidably engaged with the engagement groove of the second flange portion 16. In addition, each pin 23 slidingly contacting the engagement groove,
The side surface (for example, reference numeral 24a in FIG. 1) of the distal end of 24 is machined into a pair of parallel planes.

Such an eccentric type variable valve mechanism itself has the following features.
For example, since the configuration is well-known in Japanese Patent Application Laid-Open No. 7-119425, a detailed description thereof will be omitted, but if the center 17a of the annular disk 17 is concentric with the axis of the drive shaft 1 (see FIG. 1). State), each camshaft 11 to which the rotational motion of the drive shaft 1 is transmitted via the annular disc 17
Rotates at the same speed as the drive shaft 1 and obtains a valve lift characteristic along the profile of the cam 11a. On the other hand, when the center 17a of the annular disk 17 is eccentric from the axis of the drive shaft 1, it becomes a kind of non-uniform speed joint, and each camshaft 11 rotates at a non-uniform speed with respect to the drive shaft 1. As a result, the valve lift characteristics and the valve operating angle change according to the amount of eccentricity.

The control housing 18 for rotatably holding the annular disk 17 is a substantially triangular plate-like member along a plane orthogonal to the drive shaft 1, that is, the same plane as the annular disk 17. The control housing 18 has a substantially rectangular slider engagement groove 31 formed at the upper left position in the vehicle mounted state shown in FIG. 1, and a lower left position in FIG. 1, that is, below the slider engagement groove 31. The support shaft insertion hole 4 is provided in the vertically lower region of the horizontal width L projected on the
0 is formed. The inner periphery of the rectangular slider 35 slidably engaged with the slider engagement groove 31 is provided on a control shaft 33 provided in parallel with the drive shaft 1.
Are rotatably inserted, and the support shaft 42 is inserted through the support shaft insertion hole 40 relatively densely and rotatably.

The slider 35 has a pair of first slider blocks 3 for facilitating assembly to the control shaft 33.
5A and a second slider block 35B, and a circular eccentric cam 36 formed on the control shaft 33.
Are inserted into the engagement groove 31 in such a manner as to be sandwiched from both sides. Each of the slider blocks 35A and 35B has a centrally-circular inner peripheral surface 35 at its center in the vehicle mounted state shown in FIG.
a slides on the outer peripheral surface of the eccentric cam 36, and its outer surface 35b engages with and slides on the slide wall surface 31a of the slider engagement groove 31, respectively.

Also, both slider blocks 35A, 35B
An appropriate gap D is set between the upper ends and the lower ends thereof so as not to generate noise and the like due to contact with each other.

As with the drive shaft 1, the control shaft 33 is continuous across all cylinders, and one end of the control shaft 33 is connected to an actuator (not shown). When the control shaft 33 rotates around the axis by driving the actuator, the control housing 18 swings in a direction perpendicular to the axis around the support shaft 42 in accordance with the position of the eccentric cam 36, and the annular shape held by the control housing 18. Rotation center 1 of disk 17
7 a is eccentric from the rotation center of the drive shaft 1 and the camshaft 11.

The control shaft 33 is rotatably supported by the control shaft support member 41, and the support shaft 42 is also mounted below the control shaft support member 41.

The control shaft support member 41 includes a base 43 fixed to the upper part of the cylinder head S, and a base 4
3 and a bearing 44 for rotatably supporting the control shaft 33. The base 43 is integrally formed over all the cylinders, is engaged with a mounting groove (concavely formed in a substantially rectangular shape) formed on an upper portion of the cylinder head S, and is substantially at the center of each cylinder. Are fixed by bolts 47 and 48 in the vicinity of the spark plug mounting hole 46 formed in the hole.

Generally, when a bolt is disposed near the ignition plug mounting hole 46, an axial force of the bolt acts on a valve lifter hole (not shown) formed near the ignition plug mounting hole 46, and the valve lifter hole is deformed. There is a possibility that sliding of the valve lifter may not be smooth. In particular, the valve lifter hole on the exhaust valve side has a large thermal deformation due to high-temperature exhaust gas, and is thus greatly affected by the axial force of the bolt. Therefore, in the present embodiment, the bolt 48 on the exhaust valve side is made relatively small in diameter so that the influence of the bolt axial force on the valve lifter hole on the exhaust valve side is reduced. In addition, the bolt 47 on the intake valve side is made larger than the bolt 48 on the exhaust side, and both bolts 47, 48 are designed so that a sufficient fastening force can be obtained.

The bolt 48 on the exhaust valve side is relatively farther from the bolt 47 on the intake valve side with respect to the longitudinal center line P of the cylinder head S shown in FIG.
The deformation of the exhaust valve side valve lifter hole caused by the axial force is effectively prevented.

Further, since the bearing portion 44 of the control shaft support member 41 supports the control shaft 33 at a position adjacent to the control housing 18, bending deformation of the control shaft 33 due to valve spring reaction force is suppressed, and Has improved the position accuracy.

In FIGS. 1 and 2, the exhaust valve side cam shaft 53 is rotatably supported by the cylinder head S by an exhaust valve side cam bracket 54.

Next, the lubrication system of this embodiment will be described with reference to FIGS.

FIG. 3A is a plan view showing the control shaft 33 as a single unit.
And a fitting portion 55 rotatably supported by the bearing portion 44 of the control shaft support member 41 are formed alternately at appropriate intervals in correspondence with the three cylinders arranged in series. .

Further, inside the control shaft 33, a lubricating oil passage 61 which extends through the three sets of eccentric cams 36 and the fitting portion 55 and extends in the longitudinal direction of the shaft is formed. That is, the lubricating oil passage 61 is eccentric with respect to the axis so as to be able to penetrate the inside of the eccentric cam 36, and the open end thereof is sealed by driving a plug 62, for example.

FIGS. 3B and 3C respectively show FIGS.
It is sectional drawing which follows the BB line and CC line of (a). A first radial passage 6 extending diametrically is provided inside the eccentric cam 36.
4 and a second radial passage 64 extending in the diametrical direction is formed inside the fitting portion 55. These radial passages 64 and 65 are both
1 and constitutes a part of the lubricating oil passage 61. The lubricating oil passage 61 and the radial passages 64, 65
Are simultaneously drilled at the same processing station, for example. A circumferential groove 66 is formed around the entire circumference of the fitting portion 55, and both ends of the second radial passage 65 are open at the bottom of the circumferential groove 66.

On the other hand, inside the control shaft support member 41 shown in FIGS.
An internal passage (not shown) for introducing lubricating oil into a bearing portion with the fitting portion 55 is formed.

FIG. 4A is a plan view showing a state where the slider 35 is assembled in the slider engaging groove 31 alone.
(B) is one slider block 35A (or 35B)
FIG. 4 is a plan view when viewed from the inner peripheral side.

In each of the slider blocks 35A and 35B, an oil passage 67 extending in the radial direction is formed at a position facing each other, specifically at a central position in the vertical direction. Each oil passage 67 is provided with the eccentric cam 36 of the control shaft 33.
(FIG. 1) The inner peripheral surface 35a slidingly contacting the outer peripheral surface is formed so as to penetrate to the slider outer surface 35b engaging and slidingly contacting the wall surface 31a of the slider engaging groove 31 (FIG. 1). Has been established.

Each slider block 35A, 35B
The inner peripheral surface 35a has a groove 68 extending in the circumferential direction.
Is formed, and one end of an oil passage 67 is opened at the bottom of each groove 68. Each of the concave grooves 68 faces the outer periphery of the eccentric cam 36 in the assembled state, and is appropriately arranged in the circumferential direction so as to always face the first radial passage 64 (FIG. 3) opened on the outer periphery of the eccentric cam 36. It is extended to an appropriate length.

The lubricating oil supplied from an oil gallery (not shown) passes through an internal passage of the control shaft support member 41,
It is directly introduced into the bearing portion between the bearing portion 44 and the fitting portion 55 of the control shaft 33 to forcibly lubricate the bearing portion.

The lubricating oil, that is, the lubricating oil that has lubricated the bearing portion, is introduced into the lubricating oil passage 61 from the circumferential groove 66 formed in the control shaft 33 through the second radial passage 65. From 61, through the first radial passage 64, it is directly introduced into the sliding contact portion between the outer peripheral surface of the eccentric cam 36 and the slider inner peripheral surface 35a, and the sliding contact portion is forcibly lubricated.

The lubricating oil is supplied to each slider block 35
A is effectively supplied to the oil passage 67 through the concave groove 68 formed in each of the A and 35B, and the slider portion in which the slider outer surface 35b and the wall surface 31a of the slider engagement groove 31 slide through the oil passage 67. To lubricate this slide part forcibly.

The lubricating oil overflows from the slider engagement groove 31, flows down along the wall surface of the plate-like control housing 18, and finally returns to the oil pan.

In this embodiment, the support shaft 42 is disposed in a vertically lower area projected below the slider engagement groove 31 in the vehicle mounted state shown in FIG. Therefore, most of the lubricating oil that overflows from the slider engagement groove 31 travels along the wall surface of the control housing 18 to support the shaft 4.
2 and the support shaft 42 is
8 can be effectively lubricated.

As described above, in this embodiment, the control shaft 3
Bearing part 3, slider 35 sliding contact part, and slider 3
Using the lubricating oil that lubricates the slide portion 5 in this order, the portion where the support shaft 42 passes through the control housing 18 can be effectively lubricated. Therefore, the control shaft 33, the slider 35, and the support shaft 42 operate smoothly, and it is possible to effectively prevent the members from being bitten, worn, and fixed, and to improve the control response of the valve lift characteristics. It is planned.

In this embodiment, when the support shaft 42 lubricates the portion through which the control housing 18 is inserted, it is not necessary to separately provide a lubricating oil passage extending to the inserted portion, so that the structure is extremely simplified. .

Further, in the vehicle mounted state shown in FIG.
The slider engagement groove 31 is inclined with respect to the vertical line Y when viewed from the axial direction. More specifically, the center line Q in the sliding direction of the slider engaging groove 31 is inclined by a predetermined angle θ with respect to the vertical line Y. Therefore, the horizontal width L of the vertically lower region projected below the slider engagement groove 31 is substantially increased, and the layout flexibility of the support shaft 42 is increased.

FIG. 5 is a sectional view showing a second embodiment in which the present invention is applied to an in-line type automobile engine.
The same components as those of the embodiment are denoted by the same reference numerals.

Here, at the position vertically below the lowermost end portion 69 in the slider engagement groove 31 inclined as viewed from the axial direction,
A support shaft 42 is provided. More specifically, the axis 42a of the support shaft 42 is disposed immediately near the vertical line Y 'passing through the lowermost end portion 69.

According to the second embodiment, in addition to obtaining the same effects as the first embodiment, the lubricating oil overflows after being naturally collected in the lowermost end portion 69 of the slider engaging groove 31. Since it comes out, more lubricating oil comes to reach the support shaft 42 at a position vertically below the lowermost end portion 69,
Its lubricating effect increases.

In the V-type engine of the first embodiment shown in FIG. 1, if possible in terms of layout, the support shaft 42 should be disposed vertically below the lowermost end 69 of the slider engagement groove 31. Thereby, the same effect as in the second embodiment can be obtained.

[Brief description of the drawings]

FIG. 1 shows a first embodiment in which the present invention is applied to a V-type engine for an automobile.
Sectional drawing which follows an AA line of FIG. 2 which shows an Example.

FIG. 2 is a plan view of the engine of FIG. 1;

3 (a) is a plan view showing the control shaft of FIG. 1 alone, and FIGS. 3 (b) and 3 (c) are respectively BB of FIG. 3 (a).
Sectional drawing along line CC.

4A is a plan view showing the slider of FIG. 1 as a single unit, and FIG. 4B is a plan view of one slider block viewed from the inner peripheral side.

FIG. 5 shows a second embodiment in which the present invention is applied to an in-line engine for an automobile.
Sectional drawing which shows an Example.

FIG. 6 is a cross-sectional view showing an intake / exhaust valve drive control device for an internal combustion engine according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Drive shaft 11 ... Camshaft 17 ... Annular disk 18 ... Control housing 31 ... Slider engagement groove 33 ... Control shaft 35 ... Slider 35A, 35B ... Slider block 36 ... Eccentric cam 42 ... Support shaft 61 ... Lubricating oil passage 67 ... Oil passage 68 ... groove 69 ... lowermost end

Claims (6)

[Claims] 1. A drive shaft that rotates in synchronization with rotation of an engine, a cylindrical camshaft provided on the outer periphery of the drive shaft so as to be relatively rotatable, and having a cam on an outer periphery for driving an intake / exhaust valve; An annular disk, into which the drive shaft is freely inserted, for transmitting the rotational motion of the drive shaft to the camshaft; a plate-shaped control housing for rotatably holding the outer periphery of the annular disk; and a rotatable control housing , A slider slidably engaged with a rectangular engagement groove formed at one end of the control housing, and an eccentric cam whose outer periphery is rotatably supported by the slider inner periphery. A control shaft that swings the control housing around the support shaft in a direction perpendicular to the axis, with the slide operation of the slider being rotated about its own axis, An intake / exhaust valve for an internal combustion engine, wherein a lubricating oil passage for introducing lubricating oil to the outer periphery of the eccentric cam is formed inside the control shaft, and the support shaft is disposed in a vertically lower region of the engagement groove. Drive control device. 2. The intake / exhaust valve drive control apparatus for an internal combustion engine according to claim 1, wherein the engagement groove is inclined with respect to a vertical line when viewed from an axial direction. 3. The intake and exhaust valve drive control device for an internal combustion engine according to claim 2, wherein the support shaft is disposed vertically below a lowermost end of the engagement groove. 4. An oil passage extending from an inner peripheral surface slidably in contact with the outer periphery of the eccentric cam to an outer peripheral surface slidably engaged with a wall surface of the engagement groove, inside the slider. Item 4. An intake and exhaust valve drive control device for an internal combustion engine according to any one of Items 1 to 3. 5. The drive control device for an intake / exhaust valve of an internal combustion engine according to claim 4, wherein a concave groove extending in the circumferential direction is formed in the inner peripheral surface of the slider so as to communicate with the oil passage. . 6. The slider is divided into a first slider block engaged with one wall surface of the engagement groove and a second slider block engaged with the other wall surface of the engagement groove. An intake / exhaust valve drive control device for an internal combustion engine according to any one of claims 1 to 5, characterized in that: