JP3394390B2 - Intake and exhaust valve drive 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 an intake / exhaust valve drive control device for variably controlling the opening / closing timing of intake / exhaust valves according to the operating state of an internal combustion engine.

[0002]

As a conventional apparatus of this kind have been provided various, JP filed by the present applicant previously as one
There is one described in Japanese Patent Laid-Open No. 7-34831 .

The outline will be described with reference to FIGS. 12 to 13. This intake / exhaust valve drive control device includes a drive shaft 1 to which a rotational force is transmitted from a crankshaft of a multi-cylinder engine via a sprocket, and the drive shaft. A camshaft 2 is provided coaxially with the outer periphery of the shaft 1 so as to be relatively rotatable, and a control mechanism 3 is provided between divided ends of the camshaft 2 divided for each cylinder. Each of the camshafts 2 has two intake valves 4, 4 per cylinder on the outer periphery thereof and valve lifters 4a, 4a.
Through which a pair of cam bearings 8 and 9 on the cylinder head 7 are rotatably supported while integrally having two cams 6 and 6 which are opened against the spring force of the valve spring 5. ing.

As shown in FIG. 12, the control mechanism 3 includes an annular first flange portion 10 integrally provided at one end of each camshaft 2 and a connecting pin 11 at a predetermined outer peripheral position of the drive shaft 1. An annular second flange portion 12 that is fixed via a sleeve 12a and faces the first flange portion 10, and is interposed between both flange portions 10 and 13 and has a substantially diameter from the axis X of the drive shaft 1. Disk housing 14 which is provided so as to be swingable in the direction, and an annular disk 16 which is rotatably held via a plain bearing 13 in a large-diameter support hole provided in the inner circumference of the disk housing 14.
It has and. Also, the disc housing 14
Has one end in the diametrical direction rotatably supported by a support shaft 15 extending along the longitudinal direction of the engine on the upper end of the cylinder head 7, and the other end so as to swing by a drive mechanism. Has become. Further, on the outer peripheral portions of the first and second flange portions 10 and 12, elongated engaging grooves 17 and 18 are formed at 180 ° positions relative to each other in the radial direction, while on both side surfaces of the annular disc 16. , Pins 19 protruding in opposite directions to engage with the engaging grooves 17 and 18, respectively.
a and 19b are projected.

Then, for example, when the engine is rotating at high speed, the disk housing 14 does not swing, and the center of the annular disk 16 is aligned with the axis X of the drive shaft 1. On the other hand, when the engine is rotating at low speed, the drive mechanism 20 is used. The disc housing 14 swings around the support shaft 15 as a fulcrum, and the annular disc 16 is eccentrically moved with respect to the axis X of the drive shaft 1.

That is, for example, when the engine is rotating at high speed, the center of the disk 16 coincides with the axis X of the drive shaft 1 and the rotational phase difference between the drive shaft 1 and the camshaft 2 does not occur. Therefore, as the drive shaft 1 rotates, the cam shaft 2 rotates synchronously with the drive shaft 1 via the control mechanism 3, the operating angles of the valves by the cams 6 and 6 increase, the valve opening timing becomes earlier, and the valve closing time increases. Since the timing is delayed, the intake charging efficiency using the intake inertial force is improved.

On the other hand, in the low rotation range, the center of the disk 16 is controlled by the drive mechanism via the disk housing 14 so as to be eccentric from the axis X of the drive shaft 1.
9a and 19b slide in the radial direction along the inner peripheral surfaces of the engagement grooves 17 and 18, and when the pin 19a on one side approaches the axis X of the drive shaft 1, the pin 19b on the other side moves axially. It becomes a relationship away from X. Therefore, in this case, the disc 16
Has a higher angular velocity with respect to the drive shaft 1,
6, the angular velocity of the camshaft 2 also increases. Therefore, the camshaft 2 is in a state in which the speed is doubled with respect to the drive shaft 1.

Therefore, when the rotational phase difference between the drive shaft 1 and the cam shaft 2 changes and the angular velocity of the cam shaft 2 is relatively large, the rotational phase with respect to the drive shaft 1 is both 1.
2 advances until the speed becomes constant, and then the angular velocity of the camshaft 2 becomes relatively small, the rotational phase delays until both 1 and 2 become uniform.

Then, the same phase point exists in the middle of the minimum and maximum points of the rotational phase difference, and when the rotational phase changes, the valve opening timing before the operating angle of the valve is delayed and the same phase point occurs. After that, the valve closing timing advances, and the overall control is made small. Therefore, the valve overlap of the intake and exhaust valves is reduced, the residual gas in the combustion chamber is reduced, and stable combustion improves fuel efficiency.

[0010]

However, in the above-mentioned conventional apparatus, one end of the disk housing 14 is supported by the support shaft 15 provided at the upper end of the cylinder head 7 as described above. It is designed to swing with the swing fulcrum as a fulcrum. Therefore, since the support shaft 15 must be provided without fail, the number of parts and the size are inevitably increased.

Moreover, since the support shaft 15 is supported independently of the cam bearings 8 and 9 of the cam shaft 2 by the separate supporting mechanism on the cylinder head 7, it is further promoted to be larger. The cylinder head 7 of the device
A large installation space on the top is required, and the mountability on the engine deteriorates.

Further, since one end of the disc housing 14 is supported by the support shaft 15, the center positioning accuracy of the annular disc 16 with respect to the axis X of the drive shaft 1 is difficult to obtain.
As a result, not only the desired valve timing control cannot be obtained, but also the valve timing varies from cylinder to cylinder, which may lead to instability in the operation of the engine due to variations in output between the cylinders.

Further, as described above, the rotational force of the drive shaft 1 is transmitted to the camshaft 2 via the pins 19a and 19b and the flanges 10 and 12, so that the pins 19a and 19b are provided. The reaction force acting on is transmitted to the disc housing 14 via the annular disc 16. As shown in FIG. 13, the disc housing 14 is supported by the support shaft 15 and the drive mechanism 20 only at two positions, that is, both end portions 14a and 14b which are outer peripheral boss portions, and is formed in a relatively thin ring shape. Has been done. For this reason,
A large load generated when the cam 6 pushes down the valve lifter 4a (when the intake valve 4 is opened) is transmitted as a reaction to the upper left through the annular disc 16 and both pins 19a and 19b as shown by the arrow in FIG. Then, the disc housing 14 is likely to be deformed upward as shown by the chain double-dashed line, and the center Y of the annular disc 16 is also likely to be slightly displaced upward. Therefore, the rotational force of the drive shaft 1 is not accurately transmitted to the camshaft 2, and as a result, the desired valve timing may not be obtained.

Further, due to the above-mentioned deformation, the circularity of the inner peripheral surface of the disk housing 14 is lost, and the sliding friction resistance with the annular disk 16 becomes large.

Further, as shown in FIG. 12, the second flange portion 12 on the side of the drive shaft 1 is adapted to rotate by pressing the pin 19b from the side against the inner side surface of the engaging groove 18 as shown in FIG. As shown in 14, the reaction force (black arrow) pushed by the pin 19b acts on the drive shaft 1 from the second flange portion 12, and a bending load (broken line arrow) is generated on the drive shaft 1.
As a result, the center of rotation (axis X) of the second flange portion 12 is likely to be displaced in the radial direction together with the drive shaft 1. Therefore, also in this case, the rotation of the drive shaft 1 is not accurately transmitted to the camshaft 2 via the annular disc 16, and as a result, the desired valve timing may not be obtained.

[0016]

The present invention has been devised in view of the above-mentioned conventional circumstances. The invention of claim 1 is directed to a drive shaft which is rotationally driven by an engine and an outer periphery of the drive shaft. A camshaft that is rotatably provided and integrally has a cam for opening and closing the intake and exhaust valves on the outer periphery, and is divided into cylinders, and a first flange portion fixed to one end of each camshaft. A second flange portion that is fixed to a predetermined portion of the drive shaft and faces the first flange portion, and a substantially annular disc housing that is arranged between the two flange portions; and an eccentricity on the inner circumference of the disc housing. An annular disc, which is rotatably supported via a cam ring and whose center is eccentrically movable with respect to the axis of the drive shaft with the rotation of the disc housing, and is interposed between the annular disc and each of the flange portions. Being an annular disc A pin slidable through the engaging groove to substantially radial direction, in the intake and exhaust valves drive control device and a drive mechanism for controlling rotation of said disc housing, before
Note that both sides of the disc housing are
It is characterized in that it is rotatably supported on each outer peripheral surface.
Therefore, make sure that both sides of the disc housing are
Since it is rotatably supported on each outer peripheral surface of the j
A spindle for supporting a conventional disc housing
And a support mechanism for supporting the spindle are not required, and
The load acting on the annular disc from
The load from each pin is applied to both flanges.
The loads act in directions that act and cancel each other out.
It Therefore, it is common that no bending load is generated on the drive shaft.
Moreover, the deformation of the disc housing can be prevented.

[0017]

According to a second aspect of the present invention, the drive mechanism includes a control shaft that transmits a rotational force to the disc housing via a transmission mechanism, and an actuator that controls the rotation of the control shaft according to an engine operating state. The control shaft is rotatably supported by a cam bearing of a cam shaft. Therefore, since the bearing of the control shaft also serves as the cam bearing of the cam shaft, it is not necessary to separately provide the bearing.

According to a third aspect of the present invention, an oil supply passage is formed in the inner axial direction of the drive shaft, and the oil supply passage is formed between the outer peripheral surface of the drive shaft and the inner peripheral surface of the drive shaft insertion hole of the annular disk. An oil retaining portion that communicates with the engagement groove is formed, and a communication hole that communicates the oil supply passage and the oil retaining portion is formed on the peripheral wall of the drive shaft. Therefore, the lubrication performance of each sliding portion is improved.

[0020]

1 to 3 show a first embodiment in which an intake / exhaust valve drive control device according to the present invention is applied to an intake side of a multi-cylinder internal combustion engine, and reference numeral 21 in the drawing denotes a crankshaft of the engine. A drive shaft 22 to which a rotational force is transmitted via a sprocket is a plurality of cam shafts which are arranged on the outer periphery of the drive shaft 21 so as to be rotatable relative to each other and coaxial with the center X of the drive shaft 21. The drive shaft 21 extends in the front-rear direction of the engine, and has an oil supply passage 21a for introducing lubricating oil from the outside in the internal axis direction.

The camshaft 22 is divided from the axis-perpendicular direction for each cylinder at a predetermined position in the longitudinal direction, and the drive shaft 21 is inserted into an insertion hole 22a formed in the internal axial direction, It is rotatably supported by a cam bearing 24 provided at the upper end of the cylinder head 7 (not shown). Also, FIG.
As shown in (2), two cams 26 for integrally opening two intake valves 23 per cylinder against the spring force of a valve spring (not shown) via a valve lifter 25 are integrally provided at predetermined positions on the outer circumference. .

As shown in FIG. 1 and FIG. 2, the cam bearing 24 is provided on the main bracket 27 and a main bracket 27 extending over a cam receiving surface formed on the upper surface of the cylinder head 7. And a pair of left and right cam bolts 29 and 30 for fastening and fixing both ends of both brackets 27 and 28 together. In addition, an arcuate bearing surface 27 is formed at the center of the upper surface of the main bracket 27.
While the a is formed, an arc-shaped bearing surface 28a is formed in the center of the lower surface of the sub-bracket 28 so as to cooperate with the bearing surface 27a and bear the control shaft 44 described later.

Further, a first flange portion 31 is integrally provided at one split end portion of each cam shaft 22. The outer peripheral portion of the first flange portion 31 has a cylindrical first portion.
The pin hole 32 is formed so as to penetrate in the axial direction of the camshaft. Further, a second flange portion 33 connected to the drive shaft 21 is provided at a position facing the first flange portion 31 with a predetermined gap. This second flange portion 33
Has an outer diameter set to be the same as the outer diameter of the first flange portion 31, and integrally has a sleeve 33a fitted to a predetermined outer peripheral surface of the drive shaft 21 on the inner peripheral portion, and the sleeve 33a has a diameter Drive shaft 2 by connecting pin 34 inserted from the direction
It is connected to 1. A second pin hole 35 is formed so as to penetrate in the camshaft axial direction at the outer peripheral portion of the second flange portion 33, that is, at a position opposite to the first pin hole 32 of the first flange portion 31. Then, the first pin hole 32 and the second pin hole 35 are engaged with an annular disc 39, which will be described later.
The base ends of the second pins 36 and 37 are rotatably held.

Further, an annular disk housing 38 is provided on the outer peripheral side of the first flange portion 31 and the second flange 33.
Is provided, and an annular disk 39 is sandwiched between the flange portions 31 and 33.

As shown in FIGS. 1 and 2, the disc housing 38 has a width dimension W set to the total of the width dimensions of the first and second flange portions 31 and 33, the annular disc 39 and the entire width dimension. The eccentric cam ring 38a is integrally provided along the circumferential direction at the center position in the width direction of the inner peripheral surface, and the spur gear 40 forming a part of the transmission mechanism is formed at the center position in the width direction of the outer peripheral surface. It is provided integrally along the circumferential direction.

The disc housing 38 is
Both sides 38b, 38 centered on the eccentric cam ring 38a
The inner peripheral surface of c is rotatably supported by the flange portions 31 and 33. That is, the both side portions 38b and 38c are set to have substantially the same width dimension as the flange portions 31 and 33, and the inner diameter is set to be slightly larger than the outer diameter dimension of the flange portions 31 and 33, so that the inner circumference is Both sides have flanges 31, 3
It is rotatably and slidably supported on the outer peripheral surface of 3.

The eccentric cam ring 38a is shown in FIG.
As shown in Fig. 5, the wall thickness width changes in the circumferential direction, and the uppermost end side is set to the maximum thickness part 38d as shown in the figure, and the thickness is gradually reduced from here to the lower end side, and the whole is crescent-shaped. Is formed in. Further, the disc housing 38 is
The rotation is controlled by a drive mechanism 43 described later.

The annular disc 39 has a substantially donut plate shape, and has a relatively large insertion hole 39a through which the drive shaft 21 is inserted, and a gap S is formed between the drive shaft 21 and the insertion hole 39a. While being formed, the outer peripheral surface 39b is rotatably supported on the inner peripheral surface of the eccentric cam ring 38a. Further, as shown in FIG. 3, the first and second pin holes 32 and 35 are provided at both end surface positions corresponding to the first pin hole 32 and the second pin hole 35, respectively.
Tip part 36 formed in the width across flats of the second pins 36, 37
Engagement grooves 41 and 42, which engage the flat surfaces of a and 37a, are formed respectively. The engagement grooves 41 and 42 are formed in a long groove shape along the diameter direction of the annular disc 39, and each inner end is formed. The part communicates with the gap S. Further, the gap S functions as an oil reservoir, and communicates with the oil supply passage 21a in the drive shaft 21 via an oil hole 21b formed in the peripheral wall of the drive shaft 21 in the radial direction.

As shown in FIG. 3, the drive mechanism 43 includes a control shaft 44 provided in parallel with the upper position of the cam shaft 22, and a stepping motor 45 as an electromagnetic actuator provided at one end of the control shaft 44. It consists of

The control shaft 44 has a relatively small outer diameter, is extended in the longitudinal direction of the engine, and
Large diameter parts 44a, 44a corresponding to the cam bearings 24, 24
Is supported between the bearing surfaces 27a and 28a.
Further, between the large diameter portions 44a, 44a, there is integrally provided a tubular gear portion 46 that constitutes a part of a transmission mechanism that meshes with the spur gear 40 of the disc housing 38 to transmit the rotational force. .

The stepping motor 45 is rotationally driven by a controller 47, and the controller 47
Is configured to detect the engine speed and the load of the engine by various sensors such as a crank angle sensor and an air flow meter, and output a control signal to the stepping motor 45.

The operation of this embodiment will be described below.
First, when the engine is running at low speed, the stepping motor 45 rotates in one direction and the control shaft 44 rotates in the same direction in response to a control signal from the controller 47 that detects the operating state. As a result, the disc housing 38 is
Both flange portions 31, 3 via the gear portion 46 and the spur gear 40
3, the eccentric cam ring 38a is rotated and held at the position shown in FIG. 5, that is, at the position where the thick portion 38d is at the lowermost end, so that the center Y of the annular disk 39 is driven as shown in the drawing. The shaft 21 is eccentrically moved from the axis X of the shaft 21 to a vertically upward position. Therefore, the sliding positions of the first engaging groove 41 and the first pin 36 and the second engaging groove 42 and the second pin 37 of the annular disk 39 reciprocate in the radial direction for each rotation of the drive shaft 21, The angular velocity of the annular disc 39 changes.

That is, the first pin 36 slides in the first engagement groove 41 to approach the center Y of the annular disk 39, and the second pin 37 slides in the second engagement groove 42 to the center. When separated from Y, the annular disc 39 has a smaller angular velocity with respect to the drive shaft 21 and the angular velocity of the camshaft 22 as well, and the angular velocity ratio (wc / wd) of both 21 and 22 is the characteristic indicated by the broken line in FIG. 6A. (The above action is indicated by the * mark in FIG. 6A).
Therefore, the camshaft 22 is double decelerated with respect to the drive shaft 21.

As a result, the cam shaft 22 and the cam 26
The rotational phase difference between the drive shaft 21 and the drive shaft 21 changes as shown by the broken line in FIG. 6B. Therefore, the intake valve 23 has a smaller valve operating angle (valve timing) as shown by the broken line in FIG. 6C in the valve lift characteristic, the valve opening timing is delayed, and the valve closing timing is sufficiently advanced. Therefore, the valve overlap with the exhaust valve is reduced, combustion is improved, and fuel efficiency is improved.

On the other hand, when the engine speed is changed from the low speed range to the high speed range, a control signal is output from the controller 47, which has detected the operating state, to the stepping motor 45, and the control shaft 44 is further rotated by 180 ° in the same direction. Rotate. Therefore, as shown in FIGS. 1 and 2, the disc housing 38 is rotatably held at a position where the thick portion 38d of the eccentric cam ring 38a is the uppermost end. As a result, the center Y of the annular disc 39 is eccentrically moved from the axial center X of the drive shaft 21 to a vertically downward position. Therefore, the second engagement groove 42 of the annular disc 39 and the second pin 37
In addition, the sliding position between the first engagement groove 41 and the first pin 36 reciprocates in the radial direction of the annular disc each time the drive shaft 21 rotates, and the angular velocity of the annular disc 39 changes.

As the angular velocity of the annular disc 39 changes, the angular velocity of the camshaft 22 with respect to the drive shaft 21 increases, contrary to the low rotational speed, and the angular velocity ratio of the two 21 and 22 is as shown by the solid line in FIG. 6A. It becomes (it becomes a point of * mark in FIG. 6A). Therefore, the camshaft 22 is
It becomes a state in which the speed is doubled with respect to 1.
The rotation phase of No. 2 changes as shown by the solid line in FIG. 6B, and has a change characteristic that is substantially symmetrical to that at low rotation. Therefore, the intake valve 23 has a large valve operating angle (valve timing) while the valve lift remains constant as shown by the solid line in FIG. 6C, and the valve opening timing is earlier than when the engine speed is low. , The valve closing time is delayed. Therefore, the intake charging efficiency using the inertial intake is improved, and the output torque can be improved.

Further, in this embodiment, the disk housing 38 is not supported by the support shaft as in the conventional case, but is supported by the outer peripheral surfaces of the flange portions 31 and 33. Therefore, the support shaft and this support shaft are supported. Since a support mechanism for supporting the device is unnecessary, the number of parts can be reduced and the overall size of the device can be reduced.

Further, as the drive shaft 21 rotates, the load acting on the annular disc 39 via the pins 36 and 37 is received by the disc housing 38. The disc housing 38 has both side portions 38b and 38c. Is supported by the outer peripheral surfaces of both flange portions 31 and 33 as described above, the load C is applied to both flange portions 3 as shown in FIG.
Acts on 1,33. Then, the flange portions 31, 3
3, the pins 36 and 37 act so as to cancel the loads acting on the drive shaft 21. That is, looking at the load acting on the disc housing 38 with reference to FIG. 7, a + b = c. a is the flange 33 to the pin 37
And a load received by the annular disk 39, and b acts on the drive shaft from the flange 31 via the flanges 33 and 31, respectively. Therefore, a1 + acting on the drive shaft
The load of b1 can be offset by the load of c.

Therefore, since no bending load is applied to the drive shaft 21, it is possible to prevent deviation of valve timing due to bending of the drive shaft 21. Further, the bending of the drive shaft 21 lowers the holding rigidity of the cam shaft 22 supported by the inner peripheral surface of the drive shaft 21, and tends to cause irregular movement of the intake valve 23. By preventing the occurrence of such irregular movement, it is possible to prevent the occurrence of such irregular movement.

Further, since the deformation of the disc housing 38 can be suppressed by supporting both flange portions 31, 33, the displacement of the center Y of the annular disc 39 can be prevented,
Also from this point, the displacement of the housing can be prevented.

Moreover, the disc housing 38 includes the first flange portion 31 of the cam shaft 22 and the second flange portion of the drive shaft 21.
Since the annular disc 39 is rotatably supported by the flange portion 33, and the annular disc 39 is rotatably supported on the inner peripheral side, the positional accuracy of the rotation center of the annular disc 39 with respect to the axis X of the drive shaft 21 is obtained. It will be easier.

Further, since the control shaft 44 uses the cam bearing 24 of the cam shaft 22, that is, the bearing is supported between the bearing surfaces 27a and 28a of the main bracket 27 and the sub bracket 28 of the cam bearing 24, the control shaft 44 is separately supported. It is not necessary to provide it on the other side, and the number of parts can be reduced also in this respect.

The drive shaft 21 has a camshaft 22,
The control shaft 44 can be sequentially assembled from above the cam shaft assembly in which the pins 36, 37, the annular disc 39, the disc housing 38, etc. are integrally assembled, and the assembling work efficiency is improved.

Further, since the control shaft 44 only needs to be able to transmit the torque for rotating the disc housing 38, the control shaft 44 can be reduced in diameter, whereby the height of the sub-bracket 28 can be made sufficiently low.

The lubricating oil supplied from the oil supply passage 21a through the through hole 21b into the clearance S is supplied to the pins 36 and 3 respectively.
7, the outer peripheral surface of the annular disc 39 and the respective flange portions 31,
It is supplied to each sliding portion such as the outer peripheral surface of 33. Therefore,
Lubrication performance of each sliding part is improved and wear can be prevented. Further, the friction between the flange portions 31 and 33 and the disc housing 38 can be reduced, and the drive loss of the camshaft 22 as a whole can be reduced. In addition, each flange portion 31,
The good lubricity between 33 and the disc housing 38 prevents the disc housing 38 from rotating along with the rotation of the drive shaft 21 and the cam shaft 22, so that the rotational drive load of the step motor 45 is reduced.

Further, the first pin hole 3 of the first flange portion 31
Since No. 2 has a cylindrical shape instead of a slit shape, even if the material of the camshaft 22 is formed of a highly wear-resistant material such as chill cast iron material, the first pin hole 32 can be easily drilled. .

FIG. 8 shows a second embodiment of the present invention, in which substantially annular holding members 5 are provided at both ends of the disk housing 38.
0 and 51 are press-fitted and fixed. That is, each of the holding members 50 and 51 has a plate shape and has a large-diameter hole 5 at the center.
Each outer peripheral portion 5 is formed in an annular shape having 0a and 51a.
0b and 51b are bent inwardly, and the inner peripheral surfaces of the outer peripheral portions 50b and 51b are press-fitted and fixed to the outer peripheral surfaces of both side portions 38b and 38c of the disc housing 38. As a result, the entire periphery of the sliding contact portion between the outer peripheral surface of each flange portion 31, 33 and the inner peripheral surface of both side portions 38b, 38c of the disk housing 38 is covered.

Therefore, from the sliding contact portion, the pins 36, 3
The lubricating oil flowing along the outer surface of 7 into the sliding contact portion and the sliding portion of the eccentric cam ring 38a and the annular disk 39 is retained by each holding member 5.
It is held by 0,51. For this reason, the lubrication performance of each sliding portion is further improved, and the storability of the lubricating oil in the gap S is also improved, so that the starting torque of the camshaft 22 is reduced and the engine startability is improved. Become.

9 and 10 show a third embodiment of the present invention. Contrary to the first and second embodiments, an annular disk 39 is provided.
Further, the bottomed engagement grooves 54 and 55 are formed in the radial direction in the flange portions 31 and 33 that penetrate the cylindrical pin holes 52 and 53. Therefore, the base ends of the pins 36 and 37 are rotatably supported by the pin holes 52 and 53, and the front end parts 36a and 37a of the inner two surface widths are engaged with the engaging grooves 5.
4, 55 are slidably engaged.

Therefore, since the cylindrical pin holes 52 and 53 are formed in the annular disk 39, the annular disk 39 is formed.
The degree of freedom in selection of the material is increased, and it becomes possible to form the material, for example, with a material having high abrasion resistance, whereby the annular disk 39 can be formed sufficiently small. As a result, friction during operation can be reduced.

The present invention is not limited to the configuration of the above-described embodiment, and it is possible to support the disk housing 38, for example, not on both flange portions 31 and 33 but on the outer peripheral surface of one flange portion. . Further, the eccentric cam ring 38a can be integrally provided on the outer circumference of the annular disc 39.

[0052]

As is apparent from the above description, according to the present invention, the disk housing is formed on each outer peripheral surface of both flange portions.
Since it is supported by, the supporting shaft and the supporting mechanism for supporting the supporting shaft are not required at all, the number of parts is reduced, the manufacturing work efficiency is improved, the cost is reduced, and the entire device is made compact. Mountability to Moreover, the load
The deformation of the disc housing due to
The center of the disc can be prevented from shifting and the load on the drive shaft can be bent.
It is possible to prevent the occurrence of weight. As a result, the valve timing
A decrease in control accuracy is prevented. Also the disc housing
Circularity is maintained by preventing deformation of the ring
It is possible to suppress an increase in sliding frictional resistance with.

[0053]

[0054]

According to the second aspect of the present invention, the control shaft is used as the cam bearing of the cam shaft to support the bearing. Therefore, the number of parts is reduced as compared with the case where the control shaft bearing is provided separately. It is possible to make the device compact.

Further, according to the invention of claim 3 , the lubrication performance of each sliding portion such as the disk housing or the annular disk is improved, and the friction can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view of a main part of this embodiment.

FIG. 4 is a plan view showing a part of the present embodiment.

5 is a cross-sectional view taken along the line AA of FIG. 1 showing the operation of this embodiment.

6A is a characteristic diagram of an angular velocity ratio between a drive shaft and a camshaft in the present embodiment, B is a characteristic diagram of a rotational phase difference between the drive shaft and a camshaft corresponding to A, and C is a valve lift characteristic diagram.

FIG. 7 is a schematic diagram showing load characteristics acting on the disc housing in the present embodiment.

FIG. 8 is a sectional view of a main part showing a second embodiment of the present invention.

FIG. 9 is a cross-sectional view of the essential parts showing the third embodiment of the present invention.

10 is a sectional view taken along line BB of FIG.

FIG. 11 is a plan view showing a part of the present embodiment.

FIG. 12 is a cross-sectional view of a main part showing a conventional device.

13 is a view on arrow C of FIG.

FIG. 14 is a perspective view of a drive shaft and a second flange portion showing a load characteristic acting on the drive shaft from the pin.

[Explanation of symbols]

21 ... Drive shaft 21a ... Oil supply passage 21b ... Oil hole (communication hole) 22 ... Camshaft 23 ... Intake valve 24 ... Cam bearing 27 ... Main bracket 28 ... Sub bracket 31 ... First flange portion 33 ... Second flange portion 36, 37 ... First and second pins 38 ... Disc housing 38a ... Eccentric cam ring 39 ... Annular disk 39a ... insertion hole 40 ... Spur gear (transmission mechanism) 41, 54 ... First engaging groove 42, 55 ... Second engaging groove 43 ... Drive mechanism 44 ... Control shaft 45 ... Step Motor 46 ... Gear (transmission mechanism) S ... Gap (oil retention part)

Claims (3)

(57) [Claims] 1. A drive shaft which is rotationally driven by an engine, and a cam which is provided on the outer periphery of the drive shaft so as to be rotatable relative to the drive shaft and which opens and closes intake and exhaust valves integrally, and is divided for each cylinder. Camshafts, a first flange portion fixed to one end portion of each camshaft, a second flange portion fixed to a predetermined portion of the drive shaft and facing the first flange portion, and both flanges A disk housing having a substantially annular shape disposed between the parts, and rotatably supported on the inner circumference of the disk housing via an eccentric cam ring, and the center of the disk housing is relative to the axis of the drive shaft as the disk housing rotates. An eccentrically movable annular disc, a pin that is interposed between the annular disc and each of the flange portions, and that is slidable in the radial direction of the annular disc through an engagement groove, and the disc housing is rotated. Control In an intake / exhaust valve drive control device including a drive mechanism , both side portions of the disc housing are
An intake / exhaust valve drive control device for an internal combustion engine, which is rotatably supported on each outer peripheral surface of the . 2. The drive mechanism is the disk housing.
Control shaft that transmits rotational force to the gear via a transmission mechanism
And control the rotation of the control shaft according to the engine operating condition.
With an actuator for camming the control shaft
It is characterized by being rotatably supported by the cam bearing of the shaft
An intake / exhaust valve drive control device for an internal combustion engine according to claim 1. 3. An oil supply passage is provided in an inner axial direction of the drive shaft.
The outer peripheral surface of the drive shaft and the drive of the annular disk
Oil that communicates with the engaging groove between the inner peripheral surface of the drive shaft insertion hole
An oil supply passage and an oil are formed on the peripheral wall of the drive shaft, forming a retaining part.
It is characterized by forming a communication hole that communicates with the retaining portion.
The intake / exhaust valve drive control device for an internal combustion engine according to claim 1.