JP4516452B2 - Valve operating device for internal combustion engine - Google Patents

Description

The present invention relates to a variable BenSo location of an internal combustion engine for variably controlled in accordance with operating conditions such as the valve lift amount and operating angle of the engine valve is a suction valves and exhaust valves in the driving state of the engine.

Conventional valve operating system for internal combustion engine, have been variously provided, by ash of the known described in Patent Document 1 as one the example below.

  The variable valve operating apparatus includes a drive cam provided on an outer periphery, to which a rotational force of a crankshaft is transmitted, a transmission mechanism that converts the rotational force transmitted from the drive cam into a swinging motion, and the transmission A swing cam structure that swings by the rocker arm of the mechanism and opens and closes two intake valves per cylinder via each valve lifter, and the valve lift amount and operating angle of the intake valve are variable according to the engine drive state And a variable lift mechanism.

  This variable lift mechanism is provided with a control cam for each cylinder on the outer periphery of a single control shaft whose rotation is controlled by a drive mechanism, and the posture of the transmission mechanism such as the rocker arm is controlled by controlling the rotation of each control cam. By changing the valve lift characteristic of each intake valve via the rocking cam structure.

The oscillating cam constituting body includes a cylindrical member that is rotatably inserted in an outer periphery of the drive shaft through an internal insertion hole, and a pair of left and right portions that are integrally provided at both axial ends of the cylindrical member. And a cam surface that is provided on the lower surface of each swing cam slides on the upper surface of the valve lifter. Thus, each intake valve is opened and closed. Further, lubricating oil is supplied between the inner peripheral surface of the insertion hole of the cylindrical member and the outer peripheral surface of the drive shaft to ensure the smooth swing of the swing cam component.
JP 2004-60635 A

  By the way, in the variable valve operating apparatus, the engine performance can be sufficiently enhanced by variably controlling the valve lift amount of the intake valve by the variable lift mechanism. When the valve is operated in a tilted state on the drive shaft, the valve lift amount of each intake valve tends to vary. In particular, during the small valve lift control, the variation in the valve lift amount greatly affects the engine performance.

  Therefore, in the conventional variable valve apparatus, in order to prevent the tilting of the swing cam structure on the drive shaft, the clearance between the inner peripheral surface of the insertion hole of the cylindrical member and the outer peripheral surface of the drive shaft Is set sufficiently small.

  For this reason, the lubricating oil supplied between the inner peripheral surface of the insertion hole and the outer peripheral surface of the drive shaft tends to hinder free fluidity in the axial direction due to a small clearance between the insertion hole and the drive shaft. It has become.

  As a result, the lubricity between the inner peripheral surface of the insertion hole and the outer peripheral surface of the drive shaft decreases, and wear occurs between the two over time, which may reduce the durability of the apparatus.

The present invention has been devised in view of the actual state of the conventional valve operating device for an internal combustion engine, and the invention according to claim 1 is characterized in that, in particular, the second bearing is provided at both ends of the insertion hole of the swing cam structure. A first annular groove is formed on the inner peripheral surface of the insertion hole excluding the second bearing surface, and the lubricating oil supply portion is opened to supply the lubricating oil , and the first annular groove is sandwiched A feature is that a pair of second annular grooves are formed on both sides of the first bearing surface so that the lubricating oil supply portion does not open .

According to the present invention, and the lubricating oil supplied to the first annular groove, and the lubricating oil that has flowed into the second annular groove through the first bearing surface from the first annular groove, the inner circumference of the insertion hole Since the lubricating oil can be positively supplied between the surface and the outer peripheral surface of the swing support shaft, it is possible to always ensure a smooth swing motion of the swing cam structure. As a result, it is possible to suppress the occurrence of wear between the two.

In addition, since no annular groove is formed on both end sides of the insertion hole , that is, on the outer side in the axial direction of the second bearing surface, a large gap is formed between the inner peripheral surface of the insertion hole and the outer peripheral surface of the swing support shaft. Since there is no gap, tilting of the rocking cam structure during rocking can be prevented, and the lubricating oil that has flowed into each of the annular grooves is finally defined by the second bearing surface and the outer peripheral surface of the rocking support shaft. Since the dammed shape is obtained, it becomes possible to hold the lubricating oil in each of the annular grooves, and more effective lubricity can be obtained.

According to a second aspect of the present invention, a journal portion for bearing the swing structure is provided on an outer peripheral portion between the swing cams, and the first annular groove and the second annular groove are provided on both sides of the journal portion. It is characterized in that it is formed at a position that avoids .

According to the present invention, since the journal portion is supported by a predetermined bearing, it receives the bearing load. However, since the annular grooves are not formed on both sides of the journal portion, the journal portion Sufficient support rigidity can be obtained .

The invention according to claim 3 is characterized in that an axial width length of the first annular groove is set smaller than a width length of the second annular groove .

According to this invention, by providing a relatively large sliding area on the second bearing surface, it is possible to further suppress the inclination of the rocking cam structure and to improve the retention of the lubricating oil flowing into each annular groove. Provided .

  Embodiments of a rocking cam structure according to the present invention will be described below in detail with reference to the drawings.

  In this embodiment, the rocking cam structure is applied to the intake side of a V-type 6-cylinder internal combustion engine of a variable valve system, and the drawing of this embodiment shows a case where it is applied to one side of three cylinders. .

  That is, first, as shown in FIGS. 2 to 5, the variable valve operating device is slidably provided on the cylinder head 1 via a valve guide (not shown) and attached in the closing direction by the valve springs 3 and 3. Two intake valves 2, 2 per cylinder that is energized, a variable mechanism 4 that variably controls the valve lift amount of each intake valve 2, 2, a control mechanism 5 that controls the operating position of the variable mechanism 4, And a drive mechanism 6 which is an actuator for rotationally driving the control mechanism 5.

  The variable mechanism 4 includes a hollow drive shaft 13 rotatably supported by a bearing 14 provided on the upper portion of the cylinder head 1, and one drive cam per cylinder fixed to the drive shaft 13 by a fixing pin. 15 and supported on the outer peripheral surface of the drive shaft 13 so as to be swingable, and slidably contact the upper surfaces of the valve lifters 16 and 16 disposed at the upper ends of the intake valves 2 and 2, respectively. One oscillating cam constituting body 17 for each cylinder to be opened, and the drive cam 15 and the oscillating cam constituting body 17 are linked to each other so that the rotational force of the driving cam 15 is changed to the swinging force of the oscillating cam constituting body 17. As a transmission means.

  As shown in FIG. 3, the drive shaft 13 is arranged along the longitudinal direction of the engine, and is connected to the crankshaft of the engine via a timing chain or the like wound around a driven sprocket 7 provided at one end. The rotational force is transmitted from, and this rotational direction is set in the direction of the arrow in FIG.

  The drive shaft 13 is formed with an oil passage 13a to which lubricating oil is supplied from a main oil gallery (not shown) in the internal axial direction, and the oil passage 13a and the rocking cam structure 17 are provided on the peripheral wall. A communication hole 13b, which is a lubricating oil supply portion communicating with an insertion hole 18a of a cylindrical member 18 described later, is formed along the radial direction.

  As shown in FIG. 4A, the bearing 14 is provided at the upper end of the cylinder head 1, and a main bracket 14a that rotatably supports the drive shaft 13 via a cylindrical member 18 described later, and the main bracket 14a. And a sub bracket 14b that rotatably supports a control shaft 32, which will be described later, and both brackets 14a and 14b are fastened together by a pair of bolts 14c and 14c from above.

  The drive cam 15 has a substantially ring shape, and includes an annular cam main body and a cylindrical portion integrally provided on the outer end surface of the cam main body, and a drive shaft insertion hole is formed through the inner shaft. In addition, the axis Y of the cam body is offset from the axis X of the drive shaft 13 in the radial direction by a predetermined amount. The drive cam 15 is fixed to the drive shaft 13 through a drive shaft insertion hole at a position where it does not interfere with the valve lifters 16 and 16, and the outer peripheral surface of the cam body has an eccentric circular cam profile. Is formed.

  As shown in FIGS. 1 to 3, the rocking cam constituting body 17 is formed integrally with the steel material, and is a cylindrical member 18 that is rotatably fitted and arranged on the outer peripheral surface 13 a of the drive shaft 13. The cylindrical member 18 is composed of a pair of swing cams 19 and 19 integrally provided at both ends in the axial direction of the cylindrical member 18, and the whole swings on the drive shaft 13 via the cylindrical member 18. It is supported freely.

  The cylindrical member 18 has an insertion hole 18a through which the drive shaft 13 is inserted, and a journal portion 18b rotatably supported by the main bracket 14a at a substantially central position of the outer peripheral surface. It is integrally formed.

  The insertion hole 18a has a first annular groove 20a formed at a substantially central position in the axial direction of the inner peripheral surface, and a pair of second annular grooves 20b on both sides of the first annular groove 20a at a predetermined interval. , 20b are formed.

The first annular groove 20a has a relatively small width in the axial direction, and is set smaller than the widths of the second annular grooves 20b and 20b. On the other hand, each said 2nd annular groove 20b, 20b is formed in the left-right symmetric position centering on the centerline Q of the axial width of the 1st annular groove 20a .

  A pair of first bearing surfaces 21a and 21a are formed on both sides of the inner circumferential surface of the insertion hole 18a with the first annular groove 20a interposed therebetween, and left and right outer sides of the second annular grooves 20b and 20b. That is, a pair of second bearing surfaces 21b and 21b, which are annular support portions, are formed at both ends in the axial direction of the insertion hole 18a, respectively, in a state straddling the first bearing surfaces 21b and 21b, and The journal portion 18b is formed at a position avoiding the second annular grooves 20b and 20b.

  Furthermore, an oil hole 18c that communicates with the communication hole 13b is formed at a substantially central position of the first annular groove 20a of the cylindrical member 18 along the radial direction.

  Each of the swing cams 19 is formed in a raindrop shape and has a cam nose portion 19a extending to the tip, and a cam surface 19b is formed on each lower surface.

  The cam surface 19b includes a base circle surface on the cylindrical member 18 side and a lift surface extending in an arc shape from the base circle surface to the cam nose portion 19a. The lift surface includes a ramp portion on the base circle surface side and the lift surface. It is comprised by the head part connected to the top face of the maximum lift which it has on the front end side of the cam nose part 19a from the ramp part.

  The cam surface 19b is preliminarily hardened in advance and abuts against a predetermined position on the upper surface of each valve lifter 16 in accordance with the swing position of each swing cam 19. .

  Further, as shown in FIGS. 1 and 2, the swing cam 19 on the one side has a pin 28 for connecting to the other end portion 25b of the link rod 25 described later on the cam nose portion 19a side of the tip portion. A pin hole 19c is inserted therethrough, and a narrow width is provided in the front-rear direction of the upper surface to ensure rigidity to receive a large load from the swinging force from the link rod 25, the spring force of the valve spring 3, and the like. A rib 31 is integrally provided.

  The transmission means includes a rocker arm 23 arranged for each cylinder above the drive shaft 13, a link arm 24 that links each end portion 23a of each rocker arm 23 and each drive cam 15, and a rocker arm. 23 is provided with a link rod 25 that links the other end 23b of the cam 23 and the swing cam 19.

  The rocker arm 23 is rotatably supported by a control cam 33 which will be described later through a support hole 23c formed in a cylindrical base portion at the center. Further, the one end 23a projecting in one direction from the cylindrical base is formed with a pin hole through which the pin 26 is inserted, while the other end projecting in the other direction of the cylindrical base. 23b has a pin hole into which a pin 27 connected to one end of the link rod 25 is inserted.

  The link arm 24 includes an annular base 24a having a relatively large diameter and a projecting end 24b projecting at a predetermined position on the outer peripheral surface of the base 24a. The drive cam 15 is located at the center of the base 24a. A fitting hole 24c is formed in which the cam body is rotatably fitted, and a pin hole through which the pin 26 is rotatably inserted is formed in the protruding end 24b.

  The link rod 25 is formed in a concave shape on the side of the rocker arm 23 and is inserted into each pin hole of the other end portion 23b of the rocker arm 23 and the cam nose portion 19a of the swing cam 19 at both ends 25a and 25b. Pin insertion holes through which end portions of the pins 27 and 28 are rotatably inserted are formed.

  A snap ring that restricts the movement of the link arm 24 and the link rod 25 in the axial direction is provided at one end of each pin 26, 27, 28.

  The control mechanism 5 is provided integrally with the control shaft 32 rotatably supported by the same bearing 14 at the upper position of the drive shaft 13 and the outer peripheral surface of the control shaft 32, and serves as a rocking fulcrum of the rocker arm 23. And a control cam 33.

  As shown in FIGS. 2 to 5, the control shaft 32 is disposed in the engine longitudinal direction in parallel with the drive shaft 13, and journal portions at predetermined positions have a main bracket 14a and a sub bracket 14b of the bearing 14. Is rotatably supported between the two.

  The control cam 33 is provided for each cylinder, that is, for each rocker arm 23 and is formed in a substantially eccentric annular shape, and the position of the axis P2 is deviated from the axis P1 of the control shaft 32 by a predetermined amount. Yes.

  The drive mechanism 6 includes a housing (not shown) fixed to the rear end of the cylinder head 1, an electric motor 35 fixed to one end of the housing, and a rotational drive of the electric motor 35 provided in the housing. A ball screw transmission mechanism 36 that transmits force to the control shaft 32 is configured.

  The electric motor 35 is constituted by a proportional type DC motor, and is fixed in a state where a rectangular tip portion of a substantially cylindrical motor casing 37 seals one end opening of the housing. Further, as shown in FIG. 2, the electric motor 35 is driven by a control signal from a control unit 38 that detects the driving state of the engine.

The control unit 38 feeds back detection signals from various sensors such as a crank angle sensor 39, an air flow meter 40, a water temperature sensor 41, and a potentiometer 42 for detecting the rotational position of the control shaft 32 to feed the current engine operation. state is detected by such operation, is adapted to output a control current to the electric motor 35.

The ball screw transmission mechanism 3 6, wherein the ball screw shaft 43 disposed on the drive shaft coaxially with the electric motor 35 in the housing, the ball nut 44 is a traveling nut that is screwed to the outer periphery of the ball screw shaft 43 And a linkage arm 45 coupled to one end of the control shaft 32 along the diametrical direction, and a link member 46 linking the linkage arm 45 and the ball nut 44.

  The ball nut 44 is applied with a moving force in the axial direction while converting the rotational motion of the ball screw shaft 43 into a linear motion to the ball nut 46 via each ball.

  Hereinafter, the operation of the present embodiment will be described. First, for example, in the low-rotation operation region including the idling operation of the engine, the rotational torque transmitted to the electric motor 35 by the control current from the control unit 38 is When rotated by being transmitted to the screw shaft 43, each ball moves the ball nut 44 linearly in one direction while rolling between the ball circulation groove and the guide groove.

  As a result, the control shaft 32 is rotationally driven clockwise by the link member 46 and the linkage arm 45 as shown in FIG.

  As a result, the control cam 33 rotates with the same radius around the axis P1 of the control shaft 32 as shown in FIGS. Moving. As a result, the other fulcrum 23b of the rocker arm 23 and the pivot point of the link rod 25 move upward with respect to the drive shaft 13, so that each swing cam 19 is connected to the cam nose 19a via the link rod 25. The side is forcibly pulled up and the whole is rotated clockwise.

  Therefore, when the drive cam 15 rotates and pushes up the one end portion 23 a of the rocker arm 23 via the link arm 24, the valve lift amount is transmitted to each swing cam 19 and the valve lifter 16 via the link rod 25. The lift amount is sufficiently small.

  Therefore, in the low rotation region of such an engine, the valve lift amount becomes the smallest as shown by L1 in FIG. 6, so that the opening timing of each intake valve 2 is delayed and the valve overlap with the exhaust valve is small. Become. For this reason, improvement in fuel consumption and stable rotation of the engine can be obtained.

Further, when the process proceeds to a high engine rotation region, and when the electric motor 35 by a control signal from the control unit 38 reversely rotates, the rotational torque to rotate is transmitted to the ball screw shaft 43, with the rotation the ball The nut 44 moves linearly in the other direction via each ball.

  As a result, the control shaft 32 rotates the control cam 33 clockwise from the position shown in FIG. 4 to rotate the shaft center P2 downward as shown in FIGS. 5A and 5B. For this reason, the entire rocker arm 23 is moved toward the drive shaft 13 this time, and the other end 23b presses the cam nose 19a of the swing cam 19 downward via the link rod 25, and each swing cam 19 is rotated counterclockwise by a predetermined amount.

  Therefore, when the drive cam 15 rotates and pushes up the one end portion 23a of the rocker arm 23 via the link arm 24, the valve lift amount is transmitted to the swing cam 19 and the valve lifter 16 via the link rod 25. The lift amount increases.

  Therefore, in such a high rotation region, the valve lift amount of each intake valve 2 is maximized as indicated by L2 in FIG. 6, and 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, when the lubricating oil is supplied from the oil passage 13a in the drive shaft 13 through the communication hole 13b into the first annular groove 20a, the lubricating oil in the first annular groove 20a is supplied. Is actively supplied between the bearing surfaces 21a, 21a and the outer peripheral surface of the drive shaft 13, and further flows into the second annular grooves 20b, 20b from here, temporarily stored therein, and further from here. 2 Supplied between the bearing surfaces 21 b and 21 b and the outer peripheral surface of the drive shaft 13.

  Thus, the lubricating oil that has flowed into the first annular groove 20a and the second annular grooves 20b, 20b is formed between the first and second bearing surfaces 21a, 21a, 21b, 21b and the outer peripheral surface of the drive shaft 13. Since it is actively supplied in the meantime, the smooth rotation and swinging motion of the drive shaft 13 and the swing cam constituting body 17 can be ensured at all times. As a result, the occurrence of wear between the inner peripheral surface of the insertion hole 18a and the outer peripheral surface of the drive shaft 13 is prevented.

In addition, the annular grooves 20b and 20b are not formed at both ends of the insertion hole 18a, and the second bearing surfaces 21b and 21b have a relatively large sliding area. , since there is a large clearance between 21b and the outer peripheral surface of the drive shaft 13, it is possible to prevent inclination of the swing cam structure 17 in the oscillating, flowing to the each annular groove 20a, 2 0 b lubrication Since the oil finally becomes a dammed shape by the second bearing surfaces 21b and 21b and the outer peripheral surface of the drive shaft 13, the lubricating oil can be held in the annular grooves 20a and 20b. Thus, more effective lubricity can be obtained.

  In addition, since the plurality of annular grooves 20a, 21b, and 21b are formed on the inner peripheral surface of the insertion hole 18a, as described above, the lubricating oil supplied into the first annular groove 20a flows in the axial direction and is Since the two annular grooves 20b and 20b are supplied, the lubricity between the bearing surfaces 21a and 21b and the outer peripheral surface of the drive shaft 13 can be further improved.

  Furthermore, the lubricating oil that has flowed into the first annular groove 20a is supplied between the journal portion 18b and the inner peripheral surface (bearing hole inner peripheral surface) of the main bracket 14a through the oil hole 18c. The internal and external lubricity with respect to the cylindrical member 18 is improved, and a smoother swinging motion of the swing cam constituting body 17 can be ensured.

Further, in this embodiment, the an outer peripheral portion between the swing cam 19, together with arranging the journal portion 18b, a second annular groove 20b, 20 b to avoid both sides of the journal portion 18b Since it is formed at the position, a decrease in the support rigidity at the journal portion 18b is prevented. Therefore, a sufficient support rigidity for receiving a bearing load by the bearing 14 is obtained.

Further, the second annular groove 20b, 20 b, since the formed symmetrically position of the cylindrical member 18 across the center line Q, swing cam structure respective annular groove 20b, the lubricating oil supplied to 20b 17 can be lubricated with good balance with respect to the drive shaft 13. As a result, only one end side of the cylindrical member 18 does not wear over time.

  Further, in this embodiment, when the valve lift amount of each intake valve 2, 2 is controlled to be small by the variable mechanism 4, wear between the insertion hole 18 a and the drive shaft 13, and the swing cam structure 17 However, as described above, the swing structure 17 is stably supported by the bearing surfaces 21a and 21b. It is possible to prevent the lift amount from shifting.

  The technical ideas other than the invention described in the claims, as grasped from the embodiment, will be described below.

  (1) The swing cam structure according to claim 3, wherein both sides of the journal portion are arranged at positions where the annular groove is not formed.

  According to this invention, the same effect as that of the invention of the third aspect can be obtained.

  (2) The rocking cam structure according to (3) or (1), wherein the annular groove is formed at a symmetrical position from the center of the axial length of the insertion hole.

  According to the present invention, since the annular grooves are in the left-right symmetrical positions, the rocking cam structure can be lubricated with good balance with respect to the rocking support shaft by the lubricating oil supplied to the respective annular grooves. . As a result, only one end side of the rocking cam structure does not wear over time.

  (3) The rocking cam structure according to (3) or (1), wherein the lubricating oil supply part is constituted by an oil hole communicating with the journal part and the insertion hole.

  According to the present invention, for example, the lubricating oil that has lubricated the journal portion is supplied into the insertion hole through the oil hole, so that separate supply passages for the lubricating oil are formed for the journal portion and the insertion hole, respectively. This is no longer necessary and is advantageous in terms of cost.

  (4) The rocking cam according to any one of (1) to (3), wherein the rocking cam is driven by a variable mechanism that variably controls a valve lift amount of the engine valve in accordance with an engine driving state. Cam structure.

  If the valve lift amount of the engine valve is controlled to be small by the variable mechanism, the influence of wear between the insertion hole and the swing support shaft and the deviation of the valve lift amount due to the tilt of the swing cam structure increases. In the present invention, since the oscillating structure is stably supported, it is possible to prevent the deviation of the valve lift amount.

(5) The variable mechanism includes:
A drive shaft to which rotational force is transmitted from the crankshaft;
A motion conversion mechanism for converting the rotational motion of the drive shaft into a swing motion;
5. The rocking cam structure according to claim 4, further comprising a transmission mechanism that rocks the cam by causing rocking motion from the motion converting mechanism to act on the cam.

(6) The variable mechanism comprises:
It rotates in synchronization with the crankshaft of the engine, and is supported by a drive shaft with a drive cam provided on the outer periphery so that it can swing. The cam surface slides on the valve lifter top surface to open and close the engine valve. A swing cam;
A rocker arm having one end mechanically linked to the drive cam and the other end linked to the swing cam via a link rod;
By changing the rocking fulcrum of the rocker arm according to the engine operating state, the contact position of the cam surface of the rocking cam with the upper surface of the valve lifter is changed to make the valve lift of the engine valve variable. The rocking cam structure according to any one of claims 1 to 5, wherein

  The present invention is not limited to the configuration of each of the above embodiments. For example, as a means for supplying lubricating oil into the first annular groove 20a, the oil hole 18c is not used as the supply means. It is also possible to supply from the outside.

  Further, as the annular groove formed in the insertion hole 18a, the second annular grooves 20b and 20b are eliminated and only the first annular groove 20a is formed, and both sides of the first annular groove 20a are configured as bearing surfaces. It is also possible.

  Furthermore, the present invention can also be applied to an internal combustion engine that does not include a variable mechanism, and can also be applied to the exhaust valve side or both valve sides in addition to the intake valve side. Furthermore, the variable mechanism is not necessarily limited to that of the above embodiment. Of course, the number of cylinders of the internal combustion engine can be applied to multi-cylinders such as four cylinders and in-line six cylinders.

It is sectional drawing of the rocking cam structure used for embodiment of this invention. It is a principal part perspective view which shows the variable valve apparatus to which the cam structure of this embodiment was applied. It is a top view which shows the principal part of the variable valve operating apparatus. 4A is a view as viewed in the direction of an arrow A in FIG. 4 showing the valve closing action at the time of the minimum lift control in the variable valve apparatus, and FIG. 5B is a view taken along the arrow A in FIG. 4A is a view as viewed in the direction of an arrow A in FIG. 4 showing the valve closing action at the time of maximum lift control in the variable valve operating apparatus, and FIG. It is a valve lift characteristic view of an intake valve by the variable valve gear provided for this embodiment.

Explanation of symbols

2 ... Intake valve (engine valve)
DESCRIPTION OF SYMBOLS 4 ... Variable mechanism 5 ... Control mechanism 6 ... Drive mechanism 13 ... Drive shaft 13a ... Oil passage 13b ... Communication hole (lubricating oil supply part)
DESCRIPTION OF SYMBOLS 15 ... Drive cam 17 ... Swing cam structure 18 ... Cylindrical member 18a ... Insertion hole 18b ... Journal part 18c ... Oil hole 19 ... Swing cam 20a ... 1st annular groove 20b ... 2nd annular groove 21a ... 1st bearing surface 21b ... 2nd bearing surface (annular support part)

Claims (3)

A drive shaft to which rotational force is transmitted from the crankshaft;
A swing cam structure that is swingably provided around a swing support shaft inserted and disposed in the insertion hole, and that opens and closes a plurality of engine valves by swinging movement of the plurality of swing cams;
A motion conversion mechanism that converts the rotational motion of the drive shaft into a swing motion;
A valve operating device for an internal combustion engine, comprising: a transmission mechanism for causing the rocking motion from the motion conversion mechanism to act on the cam structure to rock the rocking cam structure;
A second bearing surface is provided at both ends of the insertion hole, and a first annular groove is formed on the inner peripheral surface of the insertion hole excluding the second bearing surface so that the lubricating oil supply portion is opened to supply the lubricating oil. In addition, a valve operating device for an internal combustion engine, characterized in that a pair of second annular grooves are formed on both sides of the first annular groove with the first bearing surface therebetween so that the lubricating oil supply portion does not open . A journal portion for bearing the swing structure is provided on an outer peripheral portion between the swing cams, and the first annular groove and the second annular groove are formed at positions avoiding both sides of the journal portion. 2. The valve operating apparatus for an internal combustion engine according to claim 1, wherein the valve operating apparatus is an internal combustion engine. 3. The valve operating apparatus for an internal combustion engine according to claim 1, wherein a width of the first annular groove in an axial direction is set smaller than a width of the second annular groove.

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