JP4484484B2 - Variable valve operating device for internal combustion engine - Google Patents

Description

  The present invention relates to a variable valve operating apparatus for an internal combustion engine including a variable mechanism that can vary a valve lift amount, which is an operation characteristic of an intake valve or an exhaust valve, which is an engine valve, according to an engine operating state. The present invention relates to an improvement in an actuator that drives the variable mechanism.

  As this type of conventional variable valve operating system for an internal combustion engine, there is one described in the following Patent Document 1 previously filed by the present applicant.

  Briefly, this variable valve operating device is applied to the intake valve side, and the shaft center is eccentric from the shaft center of the drive shaft on the outer periphery of the drive shaft rotating in synchronization with the rotation of the crankshaft. A drive cam is provided, and the rotational force of the drive cam is transmitted through a multi-link transmission mechanism, and the cam surface slides on the upper surface of the valve lifter at the upper end of the intake valve to control the intake valve. It has a swing cam that opens against the spring force of the valve spring.

  The transmission mechanism includes a rocker arm that is disposed above the swing cam and is swingably supported by the control shaft, an annular one end is fitted to the outer peripheral surface of the drive cam, and the other end is one end of the rocker arm. A link arm that is rotatably connected to the rocker, and a link rod that has one end rotatably connected to the other end of the rocker arm and the other end rotatably connected to the cam nose of the swing cam. Has been.

  The control shaft is rotatably supported by a bearing provided at the upper end of the cylinder head, and a control cam whose shaft center is eccentric from the control shaft axis by a predetermined amount is fixed to the outer peripheral surface thereof. Has been.

Then, the control shaft is rotationally controlled by an electric motor that is an actuator and a ball screw transmission means that is a speed reduction mechanism that decelerates the rotation of the electric motor, and the rotational position of the control cam is changed via the control shaft. Thus, by changing the rocking fulcrum of the rocker arm and changing the rolling contact position of the cam surface of the rocking cam with respect to the valve lifter upper surface, the valve lift amount of the intake valve is variably controlled according to the engine operating state. ing.
JP 2002-155716 A

  By the way, as is well known, in general, an internal combustion engine generates a so-called positive and negative alternating torque due to a large spring reaction force of a valve spring when an intake valve or an exhaust valve is opened or closed.

  The alternating torque is transmitted from the swing cam to the control shaft via a transmission mechanism such as a link arm or a rocker arm in the case of the conventional variable mechanism. A large torque fluctuation as shown in the waveform characteristic diagram of FIG.

  Furthermore, the alternating torque transmitted to the control shaft is transmitted to the speed reduction mechanism which is the ball screw transmission means. For this reason, in the ball screw transmission means, there is a risk that severe abnormal noise is generated due to the interference of each part due to the alternating torque in the transmission path such as the meshing part of each ball with the spiral ball groove on the outer periphery of the ball shaft and the ball groove of the ball nut. There is.

The present invention has been devised in view of the technical problem of the conventional variable valve operating device, and the invention according to claim 1 provides the control mechanism with the rotational force from the electric motor via the speed reduction mechanism. the variable valve device for an internal combustion engine to vary the operating characteristics of the engine valve to open against the spring force of the valve spring by conveying, the reduction mechanism, the rotational force from the output shaft of the electric motor Is formed, and an outer circumferential circular eccentric cam that rotates eccentrically with respect to the axis of the output shaft and a trochoidal outer teeth are formed on the outer circumferential surface, and the eccentric cam is accommodated on the inner circumference so as to be relatively rotatable. A planetary pinion gear having a circular sliding hole and rotating eccentrically according to the rotation of the eccentric cam, and a trochoidal inner tooth meshing with the outer teeth on an inner peripheral surface thereof Revolved while spinning the pinion gear And the ring gear, by converting the eccentric rotation of the planetary pinion gears concentric rotation consist of an eccentric absorbing means for transmitting the rotational force to the control mechanism that,
Lubricating oil is always supplied to a meshing portion between the outer teeth of the planetary pinion gear and the inner teeth of the ring gear .

The invention according to claim 2 makes variable the operating characteristics of the engine valve that opens against the spring force of the valve spring by transmitting the rotational force from the electric motor to the control mechanism via the speed reduction mechanism. A variable valve operating apparatus for an internal combustion engine, wherein the speed reduction mechanism receives a rotational force from an output shaft of the electric motor and rotates eccentrically with an outer peripheral circular shape with respect to an axis of the output shaft; A planetary pinion gear that forms outer teeth on the outer peripheral surface and has a circular slide hole in which the eccentric cam is accommodated in an inner periphery so as to be relatively rotatable, and rotates eccentrically according to the rotation of the eccentric cam; A ring gear that revolves while rotating the planetary pinion gear by forming inner teeth that mesh with the outer teeth on a circular inner peripheral surface, and the rotation by converting the eccentric rotation of the planetary pinion gear to concentric rotation Force transmitted to the control mechanism. Consist of an eccentric absorbing means, the meshing portion between the external teeth and the internal teeth of the ring gear of the planetary pinion gears constantly lubricating oil is characterized by being filled is supplied.

In the present invention, since the lubricating oil is constantly supplied between the inner and outer teeth by the lubricating oil in the housing, the gap between the teeth is sufficiently lubricated as well as the damper between the engaged inner and outer teeth. Since an effect is acquired, generation | occurrence | production of unusual noise can be reduced.

  Embodiments of a variable valve operating apparatus for an internal combustion engine according to the present invention will be described below in detail with reference to the drawings.

  In this embodiment, the variable valve device is applied to the intake valve side as in the prior art, and includes two intake valves per cylinder, and the valve lift amount and lift operating angle of the intake valve are determined in the engine operating state. It is designed to be variable according to.

  That is, the variable valve operating apparatus in this embodiment includes a pair of intake valves 2 and 2 slidably provided on the cylinder head 1 via a valve guide (not shown) as shown in FIGS. A variable mechanism 3 that variably controls the valve lift amount of each intake valve 2, 2, a control mechanism 4 that controls the operating position of the variable mechanism 3, and an actuator 5 that rotationally drives the control mechanism 4 are provided. .

  As shown in FIG. 2, the intake valves 2 and 2 are valve springs elastically mounted between a bottom portion of a substantially cylindrical bore housed in an upper end portion of the cylinder head 1 and a spring retainer at the upper end portion of the valve stem. It is biased in the closing direction by 6 and 6 spring force.

  The variable mechanism 3 includes an internal hollow drive shaft 7 disposed in the longitudinal direction of the engine, and a camshaft 8 disposed for each cylinder and rotatably supported coaxially on the outer peripheral surface of the drive shaft 7. A drive cam 9 fixed at a predetermined position of the drive shaft 7 and a valve lifter 10 provided integrally at both ends of the camshaft 8 and disposed at the upper end of each intake valve 2, 2. 10 and a pair of oscillating cams 11 and 11 for slidingly opening the intake valves 2 and 2, and a driving cam 9 and the oscillating cams 11 and 11. Is transmitted as the swinging force (valve opening force) of the swinging cams 11, 11.

  The drive shaft 7 is disposed along the longitudinal direction of the engine, and both ends thereof are rotatably supported by bearings (not shown) provided at the top of the cylinder head 1 and are also provided at one end. Rotational force is transmitted from the crankshaft of the engine via an external driven sprocket and a timing chain wound around the driven sprocket.

  Each of the camshafts 8 is formed in a substantially cylindrical shape along the axial direction of the drive shaft 7, and a support shaft hole that is rotatably supported on the outer peripheral surface of the drive shaft 7 is formed through the inner shaft direction. At the same time, a cylindrical journal portion 8a formed at the central position is rotatably supported by a cam bearing integrally provided at the upper end portion of the bearing.

  The drive cam 9 is formed in a substantially disc shape, and as shown in FIG. 2, a fixing cylindrical portion 9 a is integrally provided on one side portion thereof, and this cylindrical portion 9 a is connected to the drive shaft 7. Is fixed integrally to the outer periphery of the drive shaft 7 through a fixing pin 12 at a predetermined position in the axial direction, and the outer peripheral surface is formed into an eccentric cam profile, so that the shaft center Y of the drive shaft 7 is It is offset from the shaft center X by a predetermined amount in the radial direction.

  As shown in FIGS. 1 to 3, the swing cams 11 have substantially the same raindrop shape, and the base end side swings about the axis X of the drive shaft 7 via the camshaft 8. In addition, a cam surface 11 a is formed on the lower surface of the swing cam 11.

  Further, on the cam nose portion 11b side of the swing cam 11, a pin hole through which a pin 18 connected to the other end portion 15b of the link rod 15 described later is inserted is formed to penetrate both sides.

  As shown in FIGS. 1 to 3, the transmission mechanism includes a rocker arm 13 disposed above the drive shaft 7, a link arm 14 linking the one end 13 a of the rocker arm 13 and the drive cam 9, and the rocker arm 13. Link rod 15 that links the other end portion 13b of this to the cam nose portion 11b of one of the swing cams 11 is provided.

  The rocker arm 13 is formed with a support hole 13c penetratingly formed in a central cylindrical base from the lateral direction, and is supported by a control cam 20 described later via the support hole 13c so as to be swingable. The one end portion 13a has a pin 16 integrally projecting from the side of the tip portion, while the other end portion 13b has a pin 17 connected to the one end portion 15a of the link rod 15 inside the tip portion. A pin hole to be inserted is formed.

  The link arm 14 includes an annular portion 14a having a relatively large diameter and a projecting end 14b projecting at a predetermined position on the outer peripheral surface of the annular portion 14a. A fitting hole 14c is formed in the outer peripheral surface of the drive cam 9 so as to be freely rotatable, and a pin hole through which the pin 16 is rotatably inserted is formed in the protruding end 14b.

  The link rod 15 is integrally formed by press molding, the central portion is formed in a substantially U-shaped cross section, and the inside is bent into a substantially U-shape for compactness. Both end portions 15a and 15b are rotatably connected to the other end portion 13b of the rocker arm 13 and the cam nose portion 11b side of the swing cam 11 via the pins 17 and 18, respectively.

  As shown in FIGS. 1 to 3, the control mechanism 4 includes a control shaft 19 disposed above the drive shaft 7, and a swing fulcrum of the rocker arm 13 that is integrally fixed to the outer periphery of the control shaft 19. The control cam 20 is provided.

  The control shaft 19 is disposed in the longitudinal direction of the engine in parallel with the drive shaft 7 and is rotatably supported by a bracket provided at the upper end of the bearing shared with the camshaft 8. On the other hand, the control cam 20 has a cylindrical shape, and the axial center position is offset by a predetermined amount α from the axial center of the control shaft 19 by the thick portion.

  As shown in FIGS. 1 and 4 to 7, the actuator 5 is an electric motor that is a housing 21 fixed to the rear end portion of the cylinder head 1 and a rotational drive source fixed to one end wall 21 a of the housing 21. The motor 22 and a cycloid mechanism 23 that is provided inside the housing 21 and transmits a rotational driving force of the electric motor 21 to the control shaft 19 are configured.

  The housing 21 is formed in a cylindrical shape with a lid, and is arranged substantially coaxially with the axial direction of the control shaft 19, and rotatably supports a drive shaft 22 a that is an output shaft of the electric motor 22 at substantially the center of the one end wall 21 a. A support hole 21b for supporting the ball bearing 24 is formed so as to penetrate therethrough, and fixing bosses 21c to the rear end wall of the cylinder head 1 are integrally formed at four positions on the outer periphery. Further, a lubricating oil supply hole 21d for guiding the lubricating oil to the inside is formed at the upper end portion. A drain hole 1b for discharging the lubricating oil lubricated in the housing 21 is formed in the rear end wall 1a of the cylinder head 1.

  The electric motor 22 is constituted by a proportional type DC motor, and the front end portion of the motor casing is fixed to the one end wall 21a from the axial direction by a plurality of bolts 25, and the operation state of the engine is not shown. It is driven by a control signal from an electronic controller (ECU).

  This electronic controller includes various sensors such as a crank angle sensor that detects the engine speed, an air flow meter that detects the intake air amount, a water temperature sensor that detects the engine water temperature, and a potentiometer that detects the rotational position of the control shaft 19. The current engine operating state is detected by calculation and the like, and a control signal is output to the electric motor 22.

  The cycloid mechanism 23 is a power transmission member having an eccentric cam 26 fixed to the drive shaft 22a of the electric motor 22 and a sliding hole 27b slidably fitted to the outer peripheral surface of the eccentric cam 26 at the center. An annular planetary pinion gear 27 and a ring gear 28 which is fixed to the inside of the housing 21 by a plurality of bolts 29 and is linked to revolve and rotate the planetary pinion gear 27 on the inner peripheral side. And an eccentric absorption means 30 for converting the eccentric rotation of the planetary pinion gear 27 into a concentric rotation and transmitting the rotation to the control shaft 19.

  As shown in FIGS. 4 and 6 to 8, the eccentric cam 26 is fixed at a position where its center Z1 is eccentric by a predetermined amount β from the axis Z of the drive shaft 22a, and the outer peripheral surface is formed in a substantially circular shape. ing.

  The eccentric cam 26 has an outer shape formed in an eccentric circular shape, and has a fixing hole 26a through which the drive shaft 22a is fixed at a position eccentric from the center.

  The planetary pinion gear 27 is supported by the eccentric cam 26 so as to be relatively rotatable by a ball bearing 31 provided between the outer peripheral surface of the eccentric cam 26 and the sliding hole 27b, and is disposed on the entire outer peripheral surface. External teeth 27a are formed.

  The ring gear 28 has an inner diameter that is set to be slightly larger than an outer diameter of the planetary pinion gear 27, and an inner tooth 28a that meshes with the outer teeth 27a of the planetary pinion gear 27 on the inner peripheral surface. The number of teeth of the inner teeth 28a is one more than the number of teeth of the outer teeth 27a. Thereby, the rotational speed of the electric motor 22 is decelerated.

  As shown in FIGS. 1, 4, and 7, the eccentric absorbing means 30 is disposed between a front end face side of the eccentric cam 26 and a cylindrical large diameter portion 32 provided at one end portion 19 a of the control shaft 19. And a pair of annular portions 33 into which the one end portion 19a of the control shaft 19 is inserted in a loosely fitted state, and projecting integrally outward from the outer peripheral surface of the annular portion 33 along the diameter direction. The protrusions 34 and 34 having a two-surface width and one end face of the planetary pinion gear 27 protrude at a 180 ° position in the diameter direction, and slide in the longitudinal direction while being fitted to both the protrusions 34 and 34. 7 for fixing the planetary pinion gear 27 that is guided by the movement and that is pierced in the diametrical direction to the one end portion 19a of the control shaft 19 and a pair of bifurcated guide portions 35, 35 that allow movement in the vertical radial direction in FIG. A guide pin 36 inserted and fixed in the hole 19b, and both protrusions 34 of the annular portion 33; 7, sliding holes 37, 37 that allow the annular portion 33 to be slidably inserted into both end portions of the guide pin 36 and to move in the left-right direction in FIG. It consists of and.

  Therefore, when the planetary pinion gear 27 rotates eccentrically as shown in FIGS. 7 and 8, the guide portions 35 and 35 slide in the radial direction in the projections 34 and 34 of the annular portion 33, respectively. When the annular portion 33 slides further in the radial direction of 90 ° via the guide pin 36, the rotational force is applied to the control shaft 19 via the annular portion 33 while allowing the planetary pinion gear 27 to rotate eccentrically. Communicated. That is, the rotational force due to the revolution and rotation accompanying the eccentric rotation of the planetary pinion gear 27 is transmitted from the guide portions 35 and 35 to the annular portion 33 through the projection portions 34 and 34, and further through the sliding holes 37 and 37. At this time, the annular portion 33 moves freely on the guide pin 36 in the radial direction and absorbs the eccentric rotation of the planetary pinion gear 27, while the planetary pinion gear is transferred to the guide pin 36. The rotation force of 27 is transmitted to rotate the control shaft 19.

  Further, as described above, the lubricating oil is supplied into the housing 21 from the lubricating oil supply hole 21c and filled between the ball bearings 24, 31 and the inner and outer teeth 27a, 28a.

  The operation of the present embodiment will be described below. First, for example, in the low rotation range of the engine, the electric motor 22 is rotationally driven by the control signal from the controller that detects this operating state, and the eccentric cam 26 rotates eccentrically. Then, the planetary pinion gear 27 rotates eccentrically in the reverse direction via the inner and outer teeth 27a and 28a meshing with the inner peripheral side of the ring gear 28 by this eccentric rotational force. That is, the planetary pinion gear 27 revolves while rotating around the drive shaft 22a in one direction.

  As a result, the annular portion 33 is freely moved in the radial direction via the guide pin 36 while being given a reduced rotational force from the guide portions 35, 35 via the projections 34, 34, and the planetary pinion gear 27. Only the rotation of the planetary pinion gear 27 is applied to the control shaft 19 via the guide pin 36 while absorbing the eccentric rotation of the planetary pinion gear 27.

  Accordingly, as the control shaft 19 rotates in one direction, the control cam 20 causes the shaft center P2 to rotate around the shaft center P1 of the control shaft 19 with the same radius as shown in FIGS. The thick part moves away from the drive shaft 7 upward. Thereby, the pivotal support point of the other end portion 13b of the rocker arm 13 and the link rod 15 moves upward with respect to the drive shaft 7, so that each swing cam 11 is connected to the cam nose portion 11b via the link rod 15. The side is forcibly raised.

  Therefore, when the drive cam 9 rotates and pushes up the one end portion 13a of the rocker arm 13 via the link arm 14, the valve lift amount is transmitted to the swing cam 11 and the valve lifter 10 via the link rod 15. The lift amount becomes sufficiently small.

  Therefore, in the low rotation region of such an engine, the valve lift amount L1 is minimized, so that the opening timing of each intake valve 2 is delayed and the valve overlap with the exhaust valve is reduced. For this reason, improvement in fuel consumption and stable rotation of the engine can be obtained.

  On the other hand, when the engine shifts to the high rotation region, when the electric motor 22 rotates in the reverse direction by the control signal from the controller that detects this, and the eccentric cam 26 rotates in the same direction, the planetary pinion gear 27 and the ring gear 28 also rotate. The inner peripheral side of the shaft is eccentrically rotated in the opposite direction, and revolves while rotating around the drive shaft 22a in the other direction.

  As a result, the annular portion 33 receives the rotational force decelerated from the guide portions 35, 35 through the projections 34, 34, and moves freely in the eccentric direction, that is, in the radial direction while moving freely in the planetary pinion gear 27. A rotational force in the other direction is applied to the control shaft 19 through the guide pin 36 while absorbing the eccentric rotation.

  Therefore, the control shaft 19 rotates the control cam 20 clockwise from the position shown in FIG. 9, and the axis P2 moves downward. For this reason, as shown in FIGS. 10A and 10B, the rocker arm 13 as a whole moves in the direction of the drive shaft 7, and the other end portion 13 b moves the cam nose portion 11 b of the swing cam 11 downward through the link rod 15. By pressing, the entire swing cam 11 is rotated counterclockwise by a predetermined amount.

  Therefore, the contact position of the cam surface 11a with respect to the upper surface of the valve lifter 10 of the swing cam 11 moves to the cam nose portion 11b side (lift portion side). For this reason, when the drive cam 9 rotates during the opening operation of the intake valve 2 and the one end 13a of the rocker arm 13 is pushed up via the link arm 14, the lift amount with respect to the valve lifter 10 becomes sufficiently large.

  Therefore, in such a high rotation region, the valve lift amount L2 is maximized, the opening timing of each intake valve 2 is advanced, and the closing timing is delayed. As a result, the intake charging efficiency is improved and a sufficient output can be secured.

  According to this embodiment, the alternating torque generated due to the spring force of the valve springs 6 and 6 and transmitted to the control shaft 19 is, first, the guide pin 36, the annular portion 33, and the guide portion. The planet pinion gear 27 is input to the planetary pinion gear 27 via the eccentric absorbing means 30 such as 35, and rotates while revolving in the ring gear 28. That is, the two gears do not rotate coaxially, but the planetary pinion gear 27 meshes with the ring gear 28 because it rotates eccentrically (revolves) and rotates while rotating on the inner peripheral side of the ring gear 28. Interference in the positive and negative rotational directions of the alternating torque at the part does not occur.

  Further, since the eccentric cam 26 is accommodated in the sliding hole 27a of the planetary pinion gear 27 so as to be relatively rotatable, an alternating torque at the engaging portion of each ball and ball groove of the conventional ball screw transmission means is provided. The interference by does not occur.

  As a result, even if an alternating torque acts on the control shaft 19, it is not transmitted to the eccentric cam 26. As a result, it is possible to sufficiently suppress the generation of abnormal noise and to prevent the generation of a rotational load on the electric motor 22.

  Since the outer teeth 27a are formed on the outer peripheral surface of the planetary pinion gear 27 and the inner teeth 28a meshing with the outer teeth 27a are formed on the inner peripheral surface of the ring gear 28, the inner and outer teeth 27a are formed. , 28a ensures the rotation of the planetary pinion gear 27 with respect to the ring gear 28. Moreover, since the planetary pinion gear 27 rolls via the inner and outer teeth 27a and 28a as described above, even if backlash exists between the teeth 27a and 28a, the backlash between the teeth 27a and 28a is minimized. It becomes possible to limit to the limit.

  Furthermore, since it is possible to increase the apparent meshing area between each internal tooth 28a and each external tooth 27a, even if backlash due to backlash occurs, the meshing portion can be dispersed, This can prevent the generation of abnormal noise.

  Further, since the lubricating oil is always supplied between the inner and outer teeth 27a and 28a by the lubricating oil in the housing 21, the inter-teeth 27a and 28a are sufficiently lubricated as well as the meshed inner and outer teeth. Since the interference damper effect between the teeth 27a and 28a can be obtained, the generation of abnormal noise can be further prevented.

  Further, in this embodiment, since the ball bearing 31 is interposed between the eccentric cam 26 and the planetary pinion gear 27, generation of frictional resistance between the planetary pinion gear 27 and the eccentric cam 26 can be suppressed. Smooth rotation can be obtained at all times, and play between the two can be prevented.

  In addition, since each ball rolling portion of the ball bearing 31 is filled with lubricating oil, it is possible to improve lubricity and obtain an interference damper effect.

  In addition, the outer teeth 27a of the planetary pinion gear 27 and the inner teeth 28a of the ring gear 28 can be formed in an involute curve trochoidal shape, which further prevents the tooth surfaces from colliding with each other. It becomes possible.

  Further, in this embodiment, since the cycloid mechanism having a simple structure using the eccentric cam 26, the planetary pinion gear 27, and the ring gear 28 provided in the housing 21 is used, the entire apparatus can be reduced in weight and size. The mountability to the internal combustion engine is improved.

  Further, the present invention is not limited to the configuration of the above-described embodiment. For example, the rotation drive source may be a hydraulic motor other than the electric motor 22, and the power transmission member and the non-rotation It is also possible to form the inner and outer peripheral surfaces in a simple circular shape without providing the inner and outer teeth 27a and 27a between the members, and further, the power transmission member is arranged in the non-rotating member via a plurality of pins. Revolution and rotation are also possible.

  Furthermore, each bearing can be replaced with a plain bearing instead of a ball bearing. Further, as a variable mechanism, the valve timing is variably controlled by rotating the control shaft 19 or only the valve lift amount is variably controlled. It can also be applied to things.

  Moreover, as the eccentric absorption means 30, other than what was described in the said embodiment, it is also possible to comprise an Oldham joint, a plurality of circular holes, and a cylindrical protrusion inserted through the circular holes.

The technical ideas other than the invention described in the claims, as grasped from the embodiment, will be described below.
(1) The variable valve operating apparatus for an internal combustion engine according to claim 3, wherein lubricating oil is always supplied to a meshing portion between the outer teeth of the power transmission member and the inner teeth of the non-rotating member.

According to the present invention, the gap between the teeth is sufficiently lubricated by the lubricating oil supplied between the inner and outer teeth, and an interference damper effect between the meshed inner and outer teeth is obtained.
(2) The variable valve operating apparatus for an internal combustion engine according to (1), wherein the external teeth of the power transmission member and the internal teeth of the non-rotating member are each formed in a trochoid shape.

According to this invention, it becomes possible to further prevent the tooth surfaces from colliding with each other by making each of the internal and external teeth have a trochoidal shape of an involute curve.
(3) The internal combustion engine according to any one of claims 2 to (2), wherein a bearing is interposed between an outer peripheral surface of the eccentric cam and the sliding hole of the power transmission member. Variable valve gear.

According to this invention, generation of frictional resistance between the power transmission member and the eccentric cam can be suppressed, and smooth rotation can be obtained at all times, and occurrence of backlash between the two can also be prevented.
(4) The variable valve operating apparatus for an internal combustion engine according to (3), wherein the bearing is formed of a ball bearing and each ball rolling portion of the ball bearing is filled with lubricating oil.

According to this invention, in addition to the function and effect of the above-mentioned claim (3), it is possible to obtain an improvement in lubricity and an interference damper effect by the lubricating oil.
(5) The variable valve operating apparatus for an internal combustion engine according to any one of (1) to (4), wherein the variable mechanism variably controls a valve lift amount of the engine valve according to an engine operating state. .
(6) The variable valve for an internal combustion engine according to any one of (1) to (4), wherein the variable mechanism variably controls a phase of a lift center of the engine valve according to an engine operating state. apparatus.
(7) The internal combustion engine according to any one of (1) to (4), wherein the variable mechanism variably controls a valve lift and a lift operating angle of the engine valve according to an engine operating state. Variable valve gear.

It is a principal part disassembled perspective view which shows embodiment of the variable valve apparatus of this invention. It is a perspective view which shows the variable mechanism with which this embodiment is provided. It is a top view of the variable mechanism. It is sectional drawing of the actuator provided to this embodiment. It is a perspective view of the actuator. It is a front view of the actuator. It is a front view which shows the state which provided the eccentric absorption means in the cycloid mechanism of the actuator. It is a front view which shows the effect | action of the cycloid mechanism and eccentric absorption means of the actuator. A is an explanatory view showing a valve closing state during small lift control by a variable mechanism, and B is an explanatory view showing the valve opening state. A is an explanatory view showing a valve closing state during large lift control by a variable mechanism, and B is an explanatory view showing the valve opening state. It is a waveform characteristic view of the alternating torque transmitted to the control shaft due to the spring force of the valve spring.

Explanation of symbols

1 ... Cylinder head 2 ... Intake valve (engine valve)
DESCRIPTION OF SYMBOLS 3 ... Variable mechanism 4 ... Control mechanism 5 ... Actuator 6 ... Valve spring 21 ... Housing 22 ... Electric motor 23 ... Cycloid mechanism 26 ... Eccentric cam 27 ... Planetary pinion gear (power transmission member)
27a ... external teeth 27b ... sliding hole 28 ... ring gear (non-rotating member)
28a ... inner teeth 30 ... eccentric absorption means 31 ... ball bearing

Claims (4)

This is a variable valve operating device for an internal combustion engine that varies the operating characteristics of an engine valve that opens against the spring force of a valve spring by transmitting rotational force from an electric motor to a control mechanism via a speed reduction mechanism. And
The deceleration mechanism is
A rotational force is input from the output shaft of the electric motor, and an eccentric cam having a circular outer periphery that rotates eccentrically with respect to the axis of the output shaft;
A planetary pinion that has trochoidal outer teeth formed on the outer peripheral surface, and has a circular sliding hole on the inner periphery in which the eccentric cam is accommodated so as to be relatively rotatable, and rotates eccentrically according to the rotation of the eccentric cam. With gear,
A ring gear that revolves while rotating the planetary pinion gear by forming trochoid-shaped inner teeth that mesh with the outer teeth on an inner peripheral surface;
An eccentric absorbing means for converting the eccentric rotation of the planetary pinion gear into a concentric rotation and transmitting the rotational force to the control mechanism;
A variable valve operating apparatus for an internal combustion engine, characterized in that lubricating oil is constantly supplied to a meshing portion between the outer teeth of the planetary pinion gear and the inner teeth of the ring gear. This is a variable valve operating device for an internal combustion engine that varies the operating characteristics of an engine valve that opens against the spring force of a valve spring by transmitting rotational force from an electric motor to a control mechanism via a speed reduction mechanism. And
The deceleration mechanism is
A rotational force is input from the output shaft of the electric motor, and an eccentric cam having a circular outer periphery that rotates eccentrically with respect to the axis of the output shaft;
A planetary pinion gear that forms outer teeth on the outer peripheral surface and has a circular slide hole in which the eccentric cam is accommodated in an inner periphery so as to be relatively rotatable, and rotates eccentrically according to the rotation of the eccentric cam;
A ring gear that revolves while rotating the planetary pinion gear by forming inner teeth that mesh with the outer teeth on a circular inner peripheral surface;
An eccentric absorbing means for converting eccentric rotation of the planetary pinion gear into concentric rotation and transmitting the rotational force to the control mechanism;
A variable valve operating apparatus for an internal combustion engine, characterized in that a lubricating oil is constantly supplied and filled in a meshing portion between an outer tooth of the planetary pinion gear and an inner tooth of the ring gear.   The variable valve operating apparatus for an internal combustion engine according to claim 1 or 2, wherein a bearing is interposed between an outer peripheral surface of the eccentric cam and the sliding hole of the planetary pinion gear.   4. The variable valve operating apparatus for an internal combustion engine according to claim 3, wherein the bearing is formed by a ball bearing, and each ball rolling portion of the ball bearing is filled with lubricating oil.

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