KR20090019723A - Variable valve drive apparatus of internal combustion engine - Google Patents

Abstract

A variable valve drive apparatus of an internal combustion engine is provided to arrange oil hole freely by employing a crank-shaped control shaft. A variable valve drive apparatus of an internal combustion engine includes a crank-shaped control shaft(4). The control shaft comprises a main shaft(5) pivotally supported in a bracket and spin-controlled with an actuator, an eccentric shaft(6) made eccentric from the main shaft, and a plurality of webs(7) which pivotally connect the main shaft and the eccentric shaft.

Description

Variable Valve Drive Apparatus of Internal Combustion Engine

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable valve driving apparatus of an internal combustion engine that variably controls an operating state such as the valve lift amount or the operating angle of an intake valve or an exhaust valve of an internal combustion engine according to the operating state of the engine. A variable valve drive of an internal combustion engine suitable for forcibly feeding to improve lubrication performance.

Conventionally, in order to improve the lubrication performance of a variable valve drive apparatus, the variable valve drive apparatus which forcibly supplies lubricating oil to each pivot support part, such as a rocker arm and a link rod, is proposed (refer patent document 1).

This transmits the rotational force of the drive cam to the swing cam via the link arm, rocker arm and link rod to open and operate each intake valve, and at the same time, the variable to control the valve lift amount of the intake valve by the rotation of the control shaft and the control cam. It is a valve drive device. The cam nose portion is disposed on the control shaft side rather than the straight line S connecting the shaft center Q of the pin, which is the first pivot support portion, and the shaft center X of the drive shaft, and flows out from between the control cam and the rocker arm to the upper surface of the swing cam. The dropwise lubricating oil is forcibly lubricated by jumping in the direction of the pin with the spring of the swinging cam.

[Patent Document 1] Japanese Patent Application Laid-Open No. 2005-113720

By the way, since the conventional variable valve drive apparatus uses a control cam fixedly fixed to the outer circumferential surface of the control shaft as the rocker shaft as a means for rocking the rocker arm so as to oscillate and changing its rocking angle and rocking area, the control cam The amount of eccentricity of the rocker cover is limited to the size that can be accommodated without interfering with other components, and cannot be enlarged.Therefore, there is a problem that the lift characteristics of the intake valve and the timing of opening the valve are limited due to the limited movement control range of the rocking arm swinging center. .

In order to solve this problem, the eccentric shaft offset from the axial center is formed integrally with the control shaft in a crank shape, so that the eccentricity of the control shaft and the eccentric shaft can be greatly reduced to increase the amount of eccentricity. However, in the case of employing the crank-shaped control shaft as described above, the overlap between the control shaft and the eccentric shaft also becomes small, so that a straight line communicating lubricating oil passage cannot be formed inside, as in the conventional example in which the linear control shaft is adopted. The application of complex oil hole arrangements commonly employed in diameter crankshafts to control shafts formed with relatively thin shafts complicates oil hole machining and may result in stress concentrations around the oil holes. There was a problem in the method of introducing lubricating oil into the sliding part.

Accordingly, the present invention has been made in view of the above problems, and an object thereof is to provide a variable valve driving apparatus of an internal combustion engine having a supply structure of lubricating oil suitable for using a crank-shaped control shaft.

The present invention is rotatably supported by a cam bracket, is rotated in synchronization with the rotation of the engine and has a drive cam on its outer periphery, and the drive cam is arranged so as to be swingable at a different axial position, and the engine is moved by swinging. A swing cam configured to press open and close the driving valve, a link arm penetrating a drive cam formed in the drive shaft, a link rod connecting one end to the swing cam, and rotatably supported by the cam bracket. A crank-shaped control shaft consisting of a main shaft which is rotationally controlled by the main shaft, an eccentric shaft eccentric from the main shaft, a web connecting the main shaft and the eccentric shaft, and the eccentric shaft so as to be swingable. The ends of the link arms are rotatably connected and differ in axial position from the one ends. An end portion of the link rod is rotatably connected to an end swinging side, and includes a swinging arm for transmitting a driving force of the drive cam to the swinging cam by a rocking action, and the two webs that are continuous to the eccentric shaft of the control shaft. A flow path for supplying the lubricating oil supplied to the bearing surface of the cam bracket which penetrates the web on the link rod side from the main shaft to the eccentric shaft and rotatably supports the main shaft to the sliding surface between the swinging arm and the eccentric shaft ( A road was provided.

Therefore, in the present invention, the eccentric shaft of the crank-shaped control shaft composed of a main shaft rotatably supported by the cam bracket and rotationally controlled by the actuator, an eccentric shaft eccentric from the main shaft, and a web connecting the main shaft and the eccentric shaft. The end of the link rod is rotatably connected to the other end of the link arm rotatably connected to the end of the link arm at the same time as the end of the link arm. In the configuration in which the swinging arm which transmits the driving force of the drive cam to the swinging cam is rotatably supported, the web on the link rod side of the two webs continuous to the eccentric shaft of the control shaft is allowed to pass from the main shaft to the eccentric shaft. Extends the lube oil supplied to the bearing surface of the cam bracket to rotatably support the spindle; It was to install the flow passage to be supplied to the sliding surface between the eccentric shaft. For this reason, the control shaft part in which this flow path is comprised is located in the link rod side, and the swing cam is provided in the same axial direction area | region, and a relatively long axial span can be ensured, and the restriction about the diameter dimension of an oil hole, an arrangement angle, etc. is comparatively relatively Since it is small, the freedom degree of oil hole arrangement can be made high.

Hereinafter, the variable valve drive device of the internal combustion engine of this invention is demonstrated based on each embodiment.

(1st embodiment)

1 to 5 show a first example of the variable valve drive device of the internal combustion engine of the first embodiment to which the present invention is applied, FIG. 1 is a perspective view of the variable valve drive device, and FIG. 2 is a variable valve of FIG. Fig. 3 is a sectional view showing the configuration of the lubricating oil of the variable valve drive device, Fig. 4 is a sectional view showing the flow path configuration of the bearing portion, Fig. 5 is an exploded view of the oil groove of the bearing surface of the main shaft of the cam bracket. 6 is an explanatory diagram of the force acting at the intermediate operating angle of the variable valve drive device. The variable valve drive apparatus of this embodiment is provided with two intake valves per cylinder, and is applied to the internal combustion engine which variably controls the valve lift of each intake valve according to engine operation state.

1 to 3, a variable valve drive device of an internal combustion engine is fixed to a drive shaft 1 rotatably supported by a cam bracket 3 on an upper portion of a cylinder head (not shown), and fixed to the drive shaft 1 by pins or the like. The drive cam 2, the main shaft 5 and the main shaft 5 which are disposed in parallel with the drive shaft 1 at the upper position of the drive shaft 1 and are rotatably supported by the cam bracket 3 in the same manner. Control shaft 4 having an eccentric shaft 6 offset from the web 7 on both sides of the < RTI ID = 0.0 >), < / RTI > And a rocking cam 9 which is rotatably supported by the drive shaft 1 and in contact with a rocker arm 31 with a roller 32 of each intake valve 30.

The drive cam 2 and the swinging arm 8 are connected by a link arm 10, and the swinging arm 8 and the swinging cam 9 are connected by a link rod 11. The drive shaft 1 is driven by the crankshaft of the engine via a timing chain or timing belt (not shown). The drive cam 2 has a circular outer circumferential surface centered on a point offset from the shaft center of the drive shaft 1 by a predetermined amount, and the annular portion of the link arm 10 is rotatably fitted to the outer circumferential surface.

The swinging arm 8 has an arm portion 16 having a bearing bracket 15 and a connection portion to the link arm 10 and the link rod 11 with its base interposed between the eccentric shaft 6. ) Is formed by dividing into two, and by integrating both by the fastening bolts 17, a bearing hole 18 is formed between the two members so that the bearing hole 18 can be swingably fitted to the eccentric shaft 6 of the control shaft 4, The eccentric shaft 6 of the shaft 4 is rotatably supported. An end portion extending to one side of the arm portion 16 is connected to an upper end portion of the link rod 11 through a connecting pin 19, and at the same side as the tip portion, an intermediate portion slightly biased to the base portion than the tip portion. The arm portion 16 of the link arm 10 is connected via a connecting pin 20 protruding in the axial direction from the axial end of the base. That is, although the said link arm 10 and the link rod 11 are located in the same side, they are arrange | positioned in a different position in an axial direction.

The control shaft 4 is composed of a main shaft 5 rotatably supported by the cam bracket 3, and an eccentric shaft 6 eccentrically with respect to the main shaft 5 via a web 7, and a control shaft By changing the angular position of (4), the position of the eccentric shaft 6 is changed, and the swinging center position of the swinging arm 8 is changed accordingly. The axial length of the eccentric shaft 6 of the control shaft 4 is set to a length for accommodating the connecting pin 20 protruding in the axial direction from the base and the base of the swinging arm 8, so that the eccentric shaft 6 The webs 7 arranged at both ends of the c) and these link arms 10 and the link rod 11 are arranged so as not to interfere.

The swing cam 9 is integrally formed with the rocker arm 31 of each intake valve 30 on the cylindrical cam shaft 25 fitted to the outer circumference of the drive shaft 1 and rotatably supported. The lower end of the link rod 11 is connected to an end extending laterally from one swinging cam 9 via a connecting pin 21. The camshaft 25 is rotatably supported on the outer periphery of the drive shaft 1, but its end is pivotally supported on the cam bracket 3 also in the outer periphery, and the intermediate portion is swinged on the intermediate bracket 3A provided on the cylinder head. Possibly supported. On the lower surface of each oscillating cam 9, a base circular surface constituting an arc of concentricity with the drive shaft 1 and a cam surface extending by drawing a predetermined curve from the basic circular surface are formed in succession, and the basic circular surface and the cam surface are oscillating cams. The upper surface of the roller 32 of the rocker arm 31 of each intake valve 30 is in contact with the swinging position of (9).

That is, the base circular section is a section in which the lift amount becomes "0" as a base circle section, and when the rocking cam 9 swings and the cam surface contacts the roller 32 of the rocker arm 31, the intake valve 30 gradually It is going to lift. In addition, a slight lap section is provided between the base circle section and the lift section. In addition, the intake valve 30 of this embodiment is configured to be opened and closed by a rocker arm 31 with a roller 32 as shown in FIG. 2, and the base of the rocker arm 31 is supplied with lubricating oil. It is comprised so that the hydraulic lash adjuster 33 (HLA) which receives and operates may be provided.

The control shaft 4 is configured to rotate within a predetermined angle range by a control actuator 23 provided at one end. This control actuator 23 consists of an electric actuator etc., for example, and is controlled by the control signal from the engine controller which is not shown in figure. The rotation angle of the control shaft 4 is detected by a control shaft 4 sensor (not shown).

In the variable valve drive device configured as described above, when the drive shaft 1 rotates, the link arm 10 moves up and down by the cam action of the drive cam 2, and the swing arm 8 swings with it. The rocking of the rocking arm 8 is transmitted to the rocking cam 9 via the link rod 11 to rock the rocking cam 9. The rocker arm 31 is pressed by the cam action of the rocking cam 9 to act to lift the intake valve 30.

When the angular position of the control shaft 4 is changed via the control actuator 23, the initial position of the swinging arm 8 is changed to change the initial swinging position of the swinging cam 9. For example, in the low speed low load operation state of the internal combustion engine, the eccentric shaft 6 is controlled to be positioned below the drawing (close to the driving shaft 1) (clockwise position in FIG. 2) so that the swinging arm ( The base of 8) is located below, and the edge part at the side of the connecting pin 21 of the swing cam 9 is brought up relatively upward. That is, the initial position of the swing cam 9 is tilted in the direction in which the cam surface is away from the roller 32 of the rocker arm 31. Therefore, when the rocking cam 9 oscillates with the rotation of the drive shaft 1, the basic raw surface is long and continues to contact the tappet 50, and the cam surface is in contact with the roller 32 of the rocker arm 31. Is short. Therefore, the amount of lift as a whole becomes small, and the angle range from the opening time to the closing time, that is, the operating angle, is also reduced.

On the contrary, in the high-speed rotational high load operating state of the internal combustion engine, the eccentric shaft 6 is controlled so as to be located above the drawing away from the drive shaft 1 (the counterclockwise position in FIG. 2), so that the base of the swinging arm 8 is located. Is located above, and the end portion at the side of the connecting pin 21 of the swinging cam 9 is relatively lowered. 2 shows the state of the intermediate operating angle at which the maximum input load acts. That is, the initial position of the swing cam 9 is tilted in the direction in which the cam surface is close to the roller 32 of the rocker arm 31. Therefore, when the rocking cam 9 swings with the rotation of the drive shaft 1, the portion in contact with the roller 32 of the rocker arm 31 immediately shifts from the base surface to the cam surface. Therefore, the lift amount is large as a whole, and the operating angle thereof is also enlarged.

Since the initial position of the eccentric shaft 6 can be changed continuously, the valve lift characteristic is continuously changed with this. That is, both the lift and the operating angle can be continuously enlarged and reduced simultaneously. Although it depends on the layout of each part, the opening time and closing time of the intake valve 30 change substantially symmetrically, for example with the change of the lift and operation angle.

Although not shown, a phase control actuator is disposed between the sprocket driven through the timing chain or the timing belt on the crankshaft and the drive shaft 1 within the predetermined angle range, so as to relatively rotate the drive shaft 1. The control actuator may be controlled by a control signal from the engine controller to relatively rotate the sprocket and the drive shaft 1 to cause the lift center angle in the valve lift to be seismic. That is, the curve itself of the lift characteristic does not change, and the whole may be advanced or perceptual.

The drive shaft 1 is formed with a lubricating oil passage 41 formed through the inner axial direction and for introducing lubricating oil supplied from the main oil gallery 40 of the internal combustion engine. The lubricating oil introduced into the lubricating oil passage 41 includes a first lubricating oil supply path for lubricating sliding portions between the link arm 10, the driving cam 2, and the connecting pin 20, the driving shaft 1, and the oscillating cam ( 2nd lubricating oil supply path which lubricates each sliding part of the rocking arm 31 of the rocking cam 9 and the intake valve 30 between the cam shaft 25 and the drive shaft 1 of 9), and the rocking cam 9 For lubricating each sliding portion between the cam shaft 25 and the cam bracket 3 and between the cam bracket 3 and the main shaft 5 of the control shaft 4 and the swinging arm 8 and the eccentric shaft 6. It is supplied to the 3rd lubricant supply path. In addition, the lubricating oil supplied from the main gallery 40 is flowed and the lubricating oil is supplied to the hydraulic lash adjuster 33 (HLA) disposed at the base of the rocker arm 31 of the intake valve 30. Doing.

The first lubricating oil supply path is driven by the drive cam 2 and the link arm by an oil hole 42 which is formed in the thin wall portion of the drive cam 2 and the peripheral wall of the drive shaft 1 corresponding thereto in the radial direction. It is in communication with the sliding movement surface between (10). The sliding pin is connected to the pin 20 and the pin by an oil passage hole 43 which is opened in the sliding face and is opened in the pin hole of the connecting pin 20 from the inside of the projecting end of the link arm 10. It is comprised in communication with the sliding surface of a hole. Thus, the sliding portion between the link arm 10, the drive cam 2, and the connecting pin 20 is lubricated.

The second lubricating oil supply path is formed between the inner circumferential surface of the cam shaft 25 and the drive shaft 1 by an oil hole 44 penetrating along the radial direction at a circumferential wall position corresponding to the swing cam 9 of the drive shaft 1. It communicates with the sliding surface between outer peripheral surfaces. In addition, this sliding surface is opened to the rolling surface (base surface surface and cam surface) of the roller 32 of the rocker arm 31 of the rocking cam 9 by the pore which is not shown in figure. Therefore, the sliding part between the drive shaft 1 and the cam shaft 25 of the swing cam 9 and the sliding part between the rocking cam 9 and the rocker arm 31 of the intake valve 30 are lubricated. In addition, the sliding portion between the drive shaft 1 and the cam shaft 25 of the rocking cam 9 communicates with the outer periphery of the cam shaft 25 and the sliding surface of the intermediate bracket 3A via the oil hole 45, so as to communicate with each other. The sliding part of the outer periphery of the bracket 3A and the camshaft 25 is comprised, too.

The third lubricating oil supply path is connected to the inner circumferential surface of the cam shaft 25 by oil holes 46 formed through the radial direction at the circumferential wall position corresponding to the cam bracket 3 of the cam shaft 25 of the drive shaft 1. The sliding portion between the cam bracket 3 and the cam shaft 25 is first communicated with the sliding movement surface between the outer circumferential surfaces of the drive shaft 1 and subsequently by oil holes 47 penetrating radially through the cam shaft 25. Communicating. The cam bracket 3 is formed with an oil passage hole 48 whose one end is opened in the bracket face accommodating the cam shaft 25 and the other end is opened in the bracket face accommodating the main shaft 5 of the control shaft 4. It is.

The control shaft 4 has a linear inclined oil hole 50 whose one end is opened on the outer circumference of the main shaft 5 and the other end is opened on the sliding surface with the swinging arm 8 of the eccentric shaft 6. ). The opening position of the surface of the eccentric shaft 6 is arranged in proximity to the side to which the link arm 10 of the swinging arm 8 is connected. Moreover, the oil hole 51 formed in the radial direction in the eccentric shaft 6 is formed in the intermediate part of the said oblique direction oil hole 50, and this radial oil hole 51 is the swinging arm 8 Is opened on the surface of the eccentric shaft 6 at the position of the front portion to which the link rod 11 is connected.

In the case of forming the oblique direction oil hole 50, the peripheral region of the web 7 connecting the main shaft 5 and the eccentric shaft 6 is formed by either one of the intermediate bracket 3A and the swing cam 9. With the arranged area, it is relatively easy to increase the thickness in the axial direction with respect to the web 7 which has a relatively large axial dimension and is arranged on the opposite link arm 10 side. Therefore, the freedom degree of oil hole arrangement | positioning, such as the oil hole diameter of the diagonal oil hole 50 and the angle of an oil hole, can be improved by increasing the axial dimension of the said web 7.

Moreover, when the through-hole 53 which penetrates the main shaft 5 in the radial direction is formed in the inlet side of the said oblique direction oil hole 50, a ring shape is formed between the main shaft 5 and the sliding surface of the cam bracket 3. Therefore, the oil film of the lubricating oil can be formed up to every corner, and the rotation operation of the main shaft 5 is smoothed.

Thus, the third lubricant supply path is between the cam shaft 25 of the rocking cam 9 and the cam bracket 3, between the cam shaft 3 and the main shaft 5 of the control shaft 4 and the rocking arm 8 and the eccentricity. Lubricate each sliding part between the shafts 6. In addition, since lubricating oil is supplied to the sliding parts with the swinging arm 8 in both of the inclined oil hole 50 and the radial oil hole 51, the load point is lubricated with a pin point with a small amount of lubricating oil. In addition, lubricant oil can be supplied to every corner at the end where the non-uniform contact load of the sliding portion with the swinging arm 8 increases.

In the bearing surface of the cam bracket 3 which rotatably supports the main shaft 5 of the said control shaft 4, as shown in FIG. 4, the groove | channel in the part which intersects with the oil passage hole 48 in the upper and lower surfaces is shown. An oil groove 54 is formed in which the width is maximized and the width thereof becomes narrower as it moves away from the intersection in the circumferential direction. The opening of the oblique direction oil hole 50 moves along the oil groove 54 in accordance with the change in the rotational position of the control shaft 4, and passes through the opening area set by the width of the oil groove 54. The flow rate of the lubricating oil is adjusted.

Specifically, when the eccentric shaft 6 is at a small operating angle rotated to the illustrated position (point A in the drawing), the width of the oil groove 54 is set narrow and the opening area thereof is also relatively small, so that the swinging arm ( The amount of lubricating oil supplied to the sliding surface with 8) is also set relatively small. By the way, when the internal combustion engine is started and at low rotation, the amount of oil supplied to the hydraulic lash adjuster 33 is likely to be insufficient, but the hydraulic lash is reduced by reducing the amount of operating oil supplied to the third lubricant supply system. Lubricating oil can be supplied preferentially to the adjuster 33 (HLA).

Moreover, when the eccentric shaft 6 is the intermediate operating angle (point B in FIG. 5) rotated so that it may be located on the extension line of the line which connects the center of the main shaft 5 and the center of the drive shaft 1, it is shown in FIG. As described above, the postures of the link arm 10 and the link rod 11 are steepest and the input load on the part is increased. However, since the width of the oil groove 54 is set to the maximum and the opening area thereof is also maximized, the amount of lubricating oil supplied to the sliding surface with the swinging arm 8 is also set to the maximum.

In addition, when the eccentric shaft 6 has a large operating angle (C point in the figure) rotated to be located over the extension line of the line connecting the center of the main shaft 5 and the center of the drive shaft 1, the oil groove 54 Although the width of is slightly narrower than the maximum value, since the opening area is also relatively large, a sufficient amount of the amount of lubricating oil supplied to the sliding surface with the swinging arm 8 is also set.

7 to 8 show a variable valve drive device of the internal combustion engine of the second example of this embodiment. In this variable valve drive device, only the configuration on the outlet side of the inclined oil hole 50 of the third lubricating oil supply path to the sliding arm 8 with the swinging arm 8 will be described below. Differently, other structures are configured similarly to the first embodiment.

That is, in the variable valve drive device of the second embodiment, the outlet of the oblique direction oil hole 50 is opened on the front side of the sliding portion with the swinging arm 8. In addition, the inner surface (sliding surface) of the bearing bracket 15 at the base of the swinging arm 8 has an oil groove 55 extending in the axial direction as shown in Fig. 8, and both ends of the oil groove 55. Thus, oil grooves 56 extending in the circumferential direction are formed, respectively.

Therefore, also in this embodiment, the lubricating oil introduced via the inclination direction oil hole 50 is the sliding part with the swinging arm 8 in the front side by the oil groove 56 of the circumferential direction of the front side. While supplied in the circumferential direction, it is supplied to the depth side of the sliding part by the oil groove 55 in the axial direction, and is supplied to the sliding part in the circumferential direction via the oil groove 56 in the circumferential direction also on the depth side. Therefore, the lubricating oil is supplied to two places by the two circumferential oil grooves 56 connected to the slidable arm 8 by the axial oil groove 55 provided in the bearing bracket 15 in the sliding part 8. Therefore, lubricating oil can be supplied to every corner at the end where the non-uniform contact load of the sliding part with the swinging arm 8 becomes large.

In addition, in this embodiment, the oil groove 55 extended in the axial direction to the inner surface (sliding surface) of the bearing bracket 15 of the base of the swinging arm 8, and at both ends of this oil groove 55, Since the oil grooves 56 extending in the circumferential direction are formed, respectively, the inclined oil holes 50 provided in the control shaft 4 can be shortened, and the processing thereof is easy, and the hole diameter and the mounting angle You can also increase the degree of freedom. Moreover, the oil groove 55 extended in the axial direction to the inner surface (sliding surface) of the bearing bracket 15 of the base of the swinging arm 8, and extending in the circumferential direction in both ends of this oil groove 55, respectively. The oil groove 56 is formed by forming a protruding portion for oil grooves in a mold beforehand when the bearing bracket 15 is formed of a casting or the like, so that processing is inexpensive and easy.

In this embodiment, the effect described below can be exhibited.

(A) A drive shaft (1) rotatably supported by the cam bracket (3) and rotated in synchronism with the rotation of the engine, the drive shaft (1) having a drive cam (2) on its outer periphery, and an axial position with the drive cam (2). The link arm 10 which is arranged so as to be swingable differently and inserts the swing cam 9 for pressing and opening the actuating drive valve of the engine by the swing and inserts the drive cam 2 formed in the drive shaft 1. And a link rod 11 connected to one end of the swing cam 9, a main shaft 5 rotatably supported by the cam bracket 3, and rotationally controlled by an actuator 23, and the main shaft. Crank-shaped control shaft 4 composed of an eccentric shaft 6 eccentric from (5), a web 7 connecting the main shaft 5 and the eccentric shaft 6, and the eccentric shaft 6 The end of the link arm 10 is rotatably installed at one end of the An end of the link rod 11 is rotatably connected to the other swinging end of the swinging end of which the axial position is different from that of the end of the, and the driving force of the driving cam 2 is controlled by the rocking action of the swinging cam 9. The main shaft is made to penetrate through the web 7 on the side of the link rod 11 of the swinging arm 8 to be transmitted to and the web 7 which is continuous to the eccentric shaft 6 of the control shaft 4. Lubricant oil, which extends from 5) to the eccentric shaft 6 and is supplied to the bearing surface of the cam bracket 3 rotatably supporting the main shaft 5, is formed between the swinging arm 8 and the eccentric shaft 6. A flow path 50 for supplying the sliding surface is provided. That is, the part of the control shaft 4 in which this flow path 50 is comprised is located in the link rod 11 side, and the oscillation cam 9 is provided in the same axial direction area | region, and can secure a comparatively long axial span, an oil hole Since the restriction on the diameter dimension, the placement angle, and the like of 50 is relatively small, the degree of freedom of oil hole arrangement can be increased.

(B) The flow path 50 provided in the control shaft 4 is installed in the cam bracket 3 which supports the main shaft 5 of the control shaft 4 so as to be able to swing, and supports the drive shaft 1 in a rotatable manner. By communicating with the lubricating oil passage 41 penetrated through the drive shaft 1 via one flow path 48, the lubrication portion associated with the drive shaft 1 having a large input load and a sliding speed is slid by swinging. Lubrication can be given priority to the lubrication site | part related to the control shaft 4 provided with a moving part.

(C) Since the flow path 50 provided in the control shaft 4 is linearly disposed from the surface of the main shaft 5 toward the rocking arm 8 of the eccentric shaft 6 and the surface which slides, it is a straight oil hole. , Oil hole processing is easy.

(D) Among the two webs 7 continuous to the eccentric shaft 6 of the control shaft 4, the web 7 on the link load 11 side is a web (on the link arm 10 side). Since the axial dimension is formed larger than 7), the restriction on the diameter dimension, the arrangement angle, etc. of the oil hole 50 can be made still smaller, and the freedom degree of oil hole arrangement can be made still higher.

(E) The flow path 50 provided in the control shaft 4 is opened on the side biased to the link arm 10 of the surface portion of the swinging arm 8 and the eccentric shaft 6 which slides, and this flow path ( 50 is provided with a radial hole 51 which communicates with the intermediate part of 50) and is opened in the surface portion on the side away from the link arm 10, thereby supplying lubricating oil to two places, thereby pinpointing the load point with a small amount of lubricating oil. Lubrication oil can be supplied to every corner of the end portion where the non-uniform contact load of the sliding portion with the swinging arm 8 increases.

(F) The oil groove 55 extending in the axial direction and the oil groove 55 extending in the circumferential direction in communication with both ends of the oil groove 55 extending in the axial direction to the bearing surface of the eccentric shaft 6 and the sliding arm 8 which is slid. And a flow path provided in the control shaft 4 is provided on the control shaft 4 by opening on the surface of the eccentric shaft 6 so as to communicate with any one of these oil grooves 55 and 56. The oblique direction oil hole 50 can be shortened, and the processing thereof is easy, and the degree of freedom of the hole diameter and the mounting angle can also be increased. Moreover, the oil groove 55 extended in the axial direction to the inner surface (sliding surface) of the bearing bracket 15 of the base of the swinging arm 8, and extending in the circumferential direction in both ends of this oil groove 55, respectively. The oil groove 56 is formed by forming a protruding portion for oil grooves in a mold beforehand when the bearing bracket 15 is formed of a casting or the like, so that processing is inexpensive and easy.

(G) On the bearing surface of the cam bracket 3 which rotatably supports the main shaft 5 of the control shaft 4, the opening on the surface of the main shaft 5 of the flow path 50 provided in the control shaft 4 is provided. The oil groove 54 is formed in the circumferential direction so that the groove width of the oil groove 54 is changed according to the circumferential position so that the control shaft on the cam bracket 3 side, which is the lubricant supply side, and the lubricant introduction side, The supply area of lubricating oil can be adjusted according to the angular position of the control shaft 4, ie, the operating angle of the intake valve 30, with the coincidence area of the flow path opening of 4).

(H) The groove width of the circumferential oil groove 54 provided on the bearing surface of the cam bracket 3 rotatably supporting the main shaft 5 of the control shaft 4 actuates the intake valve 30. It is large in the part facing the opening of the said flow path 50 in the rotation position of the control shaft 4 made to operate by the angle, and the said flow path 50 as the rotation position of the control shaft 4 shifts to a small operating angle. By narrowing the groove width of the oil groove 54 facing the opening of the hole, it is possible to reduce the supply amount when the intake valve 30 is at a small operating angle and to increase the supply amount at a large operating angle.

(I) The groove width of the oil groove 54 in the circumferential direction provided on the bearing surface of the cam bracket 3 rotatably supporting the main shaft 5 of the control shaft 4 is the width of the oscillating cam 9. It is the largest at the intersection with the line connecting the axial center and the axial center of the main shaft 5, and is formed narrower as it is farther away, so that the eccentric shaft 6 on the extension line of the axial center of the swing cam 9 and the axial center of the main shaft 5 is formed. The amount of lubricating oil can be maximized at the time of operation at the intermediate operating angle of the intake valve 30 in which the axial center of the valve is located, and sufficient lubrication can be performed for the maximum input load at the intermediate operating angle.

(J) The flow path 50 provided in the control shaft 4 has a line connecting the flow path 48 provided in the cam bracket 3 with the shaft center of the oscillation cam 9 and the shaft center of the main shaft 5. Intake valves in which the axial center of the eccentric shaft 6 is positioned on the extension line of the axial center of the swinging cam 9 and the axial center of the main shaft 5 by coinciding with each other when the axial center of the eccentric shaft 6 is positioned at When operating at the intermediate operating angle of (30), the openings of the flow paths 48 and 50 coincide with each other so that the lubricant can be directly delivered and the supply of lubricant can be maximized, so that the maximum input load at the intermediate operating angle can be achieved. Sufficient lubrication can be performed.

(K) The drive valve type of the intake valve 30 is rocker arm 31 which swings by the swing cam 9 to open and close the intake valve 30, and a hydraulic supporting base of the rocker arm 31. The lash adjuster 33 is provided, and the hydraulic lash adjuster 33 branches from the main gallery 40 which supplies the lubricating oil to the lubricating oil passage 41 formed through the drive shaft 1, thereby lubricating oil. By supplying, the amount of oil supplied to the hydraulic lash adjuster 33 is likely to be insufficient at the start of the internal combustion engine and at low rotation, but at low load and low rotation, the lubrication system associated with the control shaft 4 is supplied. By reducing the operating flow rate to be supplied, the lubricating oil can be preferentially supplied to the hydraulic lash adjuster 33 (HLA).

1 is a perspective view of a variable valve drive device of an internal combustion engine, showing a first example of one embodiment of the present invention.

Fig. 2 is a sectional view of the variable valve drive device of Fig. 1.

Fig. 3 is a sectional view showing the configuration of a lubricating oil in the variable valve drive device.

4 is a sectional view showing a flow path configuration of a bearing portion;

5 is an exploded view of an oil groove in the bearing surface of the main shaft of the cam bracket.

6 is an explanatory view of a force acting at an intermediate operating angle of the variable valve drive device.

Fig. 7 is a sectional view showing a configuration of lubricating oil in the variable valve drive device of the internal combustion engine of the second embodiment.

Fig. 8 is a perspective view showing the structure of an oil groove provided in the bearing bracket.

<Explanation of symbols for main parts of the drawings>

DESCRIPTION OF REFERENCE NUMERALS 1 drive shaft, 2 drive cam, 3 cam bracket, 4 control shaft, 5 spindle, 6 eccentric shaft, 7 web, 8 swing arm, 9 swing cam, 10 link arm, 11 link Rod, 15: bearing bracket, 16: arm portion, 18: bearing face, 41: lubricant passage, 50, 51: oil hole, 54: oil groove

Claims (12)

A drive shaft rotatably supported by the cam bracket and rotating in synchronization with the rotation of the engine; A drive cam provided on an outer circumference of the drive shaft; A link arm connecting the drive cam provided in the drive shaft in an inserted state; A swing cam disposed at a position different from the drive cam at an axial position of the drive shaft, the swing cam configured to press the drive valve of the engine to open and close by swing; A link rod having one end rotatably connected to the swing cam; A variable valve drive device having a control shaft rotatably supported by the cam bracket and rotationally controlled by an actuator, The control shaft is a crank-shaped control shaft, a plurality of shafts rotatably supported by the cam bracket and rotationally controlled by an actuator, an eccentric shaft eccentric from the main shaft, and rotatably connecting the main shaft and the eccentric shaft. A control shaft containing a web, A swinging arm provided on the eccentric shaft so as to be swingable, the swinging arm transmitting a driving force of the drive cam to the swinging cam by a rocking action, The swinging arm has one swing end rotatably connected with the end of the link arm, the other swing end rotatably connected with the link rod, and the swing end with the other swing end. The axial position is different, A flow path for supplying lubricating oil to a sliding surface between the swinging arm and the eccentric shaft, wherein the flow path extends from the main shaft to the eccentric shaft through the web on the link rod side of the plurality of webs, the control shaft. The variable valve drive of an internal combustion engine characterized by the above-mentioned. 2. The variable valve drive device of an internal combustion engine according to claim 1, wherein the flow path provided on the control shaft communicates with a lubricating oil passage formed through the drive shaft via the flow path provided on the cam bracket. The lubricating oil supplied to the bearing surface of the cam bracket rotatably supporting the main shaft is supplied to the sliding surface between the swinging arm and the eccentric shaft via a flow path provided on the control shaft. A variable valve drive device of an internal combustion engine. The variable valve drive device of an internal combustion engine according to claim 1, wherein the flow path provided on the control shaft is formed linearly from the surface of the main shaft toward the surface on which the eccentric shaft slides with the swinging arm. The variable valve drive device of an internal combustion engine according to claim 1, wherein the web on the link rod side of the two webs continuous to the eccentric shaft of the control shaft has an axial width longer than the web on the link arm side. . 2. The flow path provided in the control shaft is opened on a side close to the link arm among the surface portions of the swinging arm and the eccentric shaft that slides, and communicates with the intermediate portion of the flow path and is located far from the link arm. And a radial hole opening in said surface portion. 2. The bearing surface of the swinging arm which slides with the eccentric shaft is provided with an oil groove extending in the axial direction, and an oil groove extending in the circumferential direction in communication with both ends of the oil groove. The flow path provided in the opening of the variable valve drive of the internal combustion engine, characterized in that the opening on the surface of the eccentric shaft to communicate with any one of these oil grooves. An oil groove is formed in the circumferential direction of the bearing surface which supports the main shaft of the control shaft of the said cam bracket in communication with the opening of the main shaft surface of the flow path provided in the said control shaft, and the groove width of this oil groove is circumferential. A variable valve drive device for an internal combustion engine, characterized by a difference in directional position. 8. The groove width of the oil groove in the circumferential direction provided on the bearing surface supporting the main shaft of the control shaft of the cam bracket is characterized in that the flow path in the rotational position of the control shaft for operating the intake valve at a large operating angle. A variable valve drive apparatus for an internal combustion engine, characterized by a large groove in a portion facing the opening, and a narrow groove width of the oil groove facing the opening of the flow path as the rotational position of the control shaft moves to a small operating angle. The groove width of the oil groove of the circumferential direction provided in the bearing surface which supports the main shaft of the control shaft of the said cam bracket is the most in the part which cross | intersects the line which connects the shaft center of the said rocking cam and the shaft center of a main shaft. A variable valve drive of an internal combustion engine, characterized in that it is formed larger and narrower as it goes further. The flow path provided in the control shaft and the flow path provided in the cam bracket coincide with each other when the axial center of the eccentric shaft is positioned on a line connecting the shaft center of the swinging cam and the shaft center of the main shaft. The variable valve drive device of the internal combustion engine. The drive valve type of the intake valve according to claim 1, further comprising a rocker arm swinging by a swing cam to open and close the intake valve, and a hydraulic lash adjuster supporting a base of the rocker arm. The lash adjuster is a variable valve drive device for an internal combustion engine, characterized in that the lubricating oil is supplied from the main gallery that supplies the lubricating oil to the lubricating oil passage formed through the drive shaft.

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