KR20050076633A - Valve operating apparatus of internal combustion engine - Google Patents

Abstract

The present invention allows the intake valve to start opening the valve in a state where the pressure in the combustion chamber is low, thereby preventing or suppressing backflow of the intake air and suppressing a decrease in fuel efficiency performance due to a decrease in the effective expansion ratio.

The valve characteristic variable mechanism M of the actuating valve device 40 controls the internal EGR rate by controlling the overlap period and the non-overlap period. The valve characteristic variable mechanism M includes a control mechanism M3 for swinging the intake link mechanism connected to the intake cam and the exhaust link mechanism connected to the exhaust cam 54 about the camshaft 50, and the control mechanism M3. A driving mechanism for driving) is provided. As for the control mechanism M3, the perception amount of the opening timing of the intake valve 22 by the intake link mechanism with respect to the same drive amount of the drive mechanism in the increase direction of the internal EGR rate is the exhaust valve 23 by the exhaust link mechanism. The drive mechanism and each link mechanism are connected so as to be larger than the advance amount at the closing timing of the step.

Description

VALVE OPERATING APPARATUS OF INTERNAL COMBUSTION ENGINE}

The present invention relates to an operation valve device of an internal combustion engine having a valve characteristic variable mechanism for controlling valve operating characteristics of an intake valve and an exhaust valve. It is directed to an actuating valve device of an internal combustion engine in which the internal EGR rate is controlled by controlling the overlap period and the non-overlap period by changing.

It is known that internal EGR, which leaves a part of the gas already burned in the combustion chamber, reduces the pumping loss of the internal combustion engine, thereby improving fuel efficiency, and reducing NOx in the exhaust gas, thereby improving the exhaust purification performance. And in order to perform internal EGR, as an apparatus which controls the valve operation characteristic of an intake valve and an exhaust valve, there exists a variable operation valve apparatus of an internal combustion engine disclosed by patent document 1, for example. This variable actuation valve apparatus is provided with the variable actuation valve mechanism on the intake valve side and the exhaust valve side. Each variable actuating valve mechanism includes an eccentric cam fixed to a drive shaft rotating in conjunction with a crankshaft, a ring-shaped link rotatably fitted to an outer circumference of the eccentric cam, and a control shaft disposed substantially parallel to the drive shaft. A rocker arm that is rotatably fitted to the outer circumference of the drive cam eccentrically fixed to and pivotally mounted at one end to the ring-shaped link, and is rotatably fitted to the drive shaft and connected via a link to the other end of the rocker arm A swinging cam. The swing cam for opening and closing the intake valve and the exhaust valve is operated in accordance with the maximum lift amount of the intake valve and the exhaust valve by rotating the control shaft in accordance with the engine operation state and changing the distance between the rocking center swing center and the rotation center of the drive shaft. Swing to change the angle. As the maximum lift amount of the intake valve and the exhaust valve decreases, the control shaft is rotationally controlled so that the maximum lift timing moves to the perceptual side in the intake valve and to the advance side in the exhaust valve. As a result, the valve opening timing of the intake valve is perceived to be larger than the width of the advance angle of the valve closing timing, and the valve closing timing of the exhaust valve is advanced to a width larger than the width of the perception of the valve opening timing, and the combustion chamber It is possible to improve fuel efficiency and to clean the exhaust gas using the combustion gas remaining in the gas.

<Patent Document 1> Japanese Unexamined Patent Application Publication No. 2001-3721

By the way, when the internal EGR is performed, if the pressure of the combustion chamber is high when the intake valve opens the valve by the gas already burned in the combustion chamber, backflow of intake occurs and it is difficult for air of the required air amount to flow into the combustion chamber. Become. Therefore, when the internal EGR ratio is increased by decreasing the overlap period or increasing the non-overlap period, in order to prevent or prevent the back flow of intake air and to allow the required amount of air to flow into the combustion chamber, the combustion chamber is opened at the time of opening the intake valve. The lower the pressure, the more preferable. Moreover, in the said prior art, since the drive shaft and the control shaft are provided in each variable actuating valve mechanism on the intake valve side and the exhaust valve side, the variable mechanism for controlling the valve operating characteristics of the intake valve and the exhaust valve is enlarged. . In addition, when the opening / closing time of the intake valve or the exhaust valve is advanced or late, if the opening time of the exhaust valve is too late, the exhaust loss of the combustion gas increases, and the thermal efficiency is lowered. Is not sufficiently sucked, the output is lowered, or the combustion becomes unstable.

This invention is made | formed in view of such a situation, The invention of Claims 1 thru | or 3 is an object of making an intake valve start valve opening in the state in which the pressure of a combustion chamber is low, and preventing or suppressing backflow of intake air. . Moreover, the invention of Claims 2 and 3 aims at downsizing the valve characteristic variable mechanism and simplification of the structure, and the invention of Claim 4 aims at simplifying the structure of the valve characteristic variable mechanism. The purpose.

The invention according to claim 1 is provided with a valve characteristic variable mechanism for respectively controlling valve operating characteristics of the intake valve and the exhaust valve, wherein the valve characteristic variable mechanism changes the opening and closing times of the intake valve and the exhaust valve so that the overlap period and In an operating valve apparatus of an internal combustion engine whose internal EGR rate is controlled by controlling a non-overlap period, the valve characteristic variable mechanism includes a cam shaft rotating in conjunction with a crank shaft of the internal combustion engine, and the intake valve in accordance with the rotation of the cam shaft. An intake interlock mechanism connected to the intake cam for opening and closing the engine; an exhaust interlock mechanism connected to the exhaust cam for opening and closing the exhaust valve according to the rotation of the cam shaft; and control for oscillating each interlock mechanism about the cam shaft. Mechanism, and a drive mechanism for driving the control mechanism, wherein the control mechanism comprises: When driven by the drive mechanism in the direction of increasing the internal EGR rate due to a decrease in the lap period or an increase in the non-overlap period, the amount of perception of the opening timing of the intake valve by the intake interlock mechanism is the exhaust interlock mechanism. It is an operation valve apparatus of the internal combustion engine which connects the said drive mechanism and each said interlocking mechanism so that it may become larger than the advance amount of the closing timing of the said exhaust valve by this.

According to this, when the valve characteristic variable mechanism decreases the overlap period in the direction in which the internal EGR rate increases or increases the non-overlap period, the perceived amount of the opening timing of the intake valve is the advance amount of the closing timing of the exhaust valve. Since the closing time of the exhaust valve is advanced and the pressure of the already burned gas remaining in the combustion chamber is increased, the intake valve at the valve opening of the intake valve is less than the advance amount of the closing timing of the exhaust valve. Opens the valve when the pressure in the combustion chamber is lower.

In the invention according to claim 2, in the actuating valve device of the internal combustion engine according to claim 1, the control mechanism is driven by the drive mechanism and is movable in a direction parallel to a reference plane including a rotation centerline of the camshaft. And an intake control link pivotally mounted to the control member at a first intake connection portion and pivotally mounted at the intake linkage mechanism at a second intake connection portion, and at the first exhaust connection portion to the control member and pivotally mounted at the second exhaust connection portion; An exhaust control link pivotally mounted to the exhaust linkage mechanism, wherein a pivot drive centerline of the first intake connection portion and a pivot drive centerline of the first exhaust connection portion are disposed parallel to the rotation centerline on one side with respect to the reference plane; And a pivot drive centerline of the second intake connecting portion is disposed on the one side, and the second exhaust Pivot drive center line of the associated can, by being placed on the other side with respect to the reference plane, to when said control member is moved, wherein the intake interlocking mechanism than the swing in a large shaking motion amount about said cam axis, wherein the exhaust interlocking mechanism.

According to this, when the control member common to the intake interlock mechanism and the exhaust interlock mechanism moves in order to obtain a valve operating characteristic in which the perceived amount at the opening timing of the intake valve is larger than the advance amount at the closing timing of the exhaust valve, the pivot of the first intake connecting portion is moved. A pivot drive center line of the drive center line and the first exhaust connection part is disposed on one side with respect to the reference plane, a pivot drive center line of the second intake connection part is arranged on the one side, and the pivot drive center line of the second exhaust connection part is the reference. By being disposed on the other side with respect to the plane, the intake control link and the exhaust control link are pivotally mounted at the pivot drive centerline of the second intake connection portion and the pivot drive centerline of the second exhaust connection portion, respectively, which are arranged separately on both sides of the reference plane. The intake interlocking mechanism and the exhaust interlocking mechanism are characterized in that the swing amount of the intake interlocking mechanism Such that, the rocking cam to the center axis.

In the invention according to claim 3, in the operating valve apparatus of the internal combustion engine according to claim 1, the control mechanism is driven by the drive mechanism and is movable in a direction parallel to a reference plane including a rotation centerline of the camshaft. And an intake control link pivotally mounted to the control member at a first intake connection and pivotally mounted to the intake linkage at a second intake connection, and at the second exhaust connection to the control member at a first exhaust connection. An exhaust control link pivotally mounted to the exhaust linkage mechanism, wherein a pivot drive centerline of the first intake connection portion and a pivot drive centerline of the first exhaust connection portion are disposed in parallel to the rotation centerline, A pivot drive centerline is disposed on one side with respect to the reference plane, and pivots the second exhaust connection portion. The center line is disposed on the other side with respect to the reference plane, and the link length of the intake control link is longer than the link length of the exhaust control link, so that when the control member moves, the intake interlocking mechanism The oscillation is performed around the camshaft with a larger amount of swing than the exhaust linkage mechanism.

According to this, when the control member common to the intake interlock mechanism and the exhaust interlock mechanism moves in order to obtain a valve operating characteristic in which the perception amount at the opening timing of the intake valve is larger than the advance amount at the closing timing of the exhaust valve, the link length is exhaust control link. An intake interlock mechanism and an exhaust interlock mechanism pivotally mounted at a pivot drive centerline of the second intake connection portion and a pivot drive centerline of the second exhaust connection portion, each of which has a longer intake control link and an exhaust control link disposed separately on both sides of the reference plane. The swing is made around the cam shaft so that the swing amount of the intake interlock mechanism is larger than the swing amount of the exhaust linkage mechanism.

In the invention according to claim 4, in the operation valve device of the internal combustion engine according to any one of claims 1 to 3, the intake interlocking mechanism rotates the cam shaft when the intake interlocking mechanism is swung by the control mechanism. An intake pivot drive unit having a pivot drive center line that swings about a center line, wherein the exhaust linkage mechanism includes a pivot drive center line that swings about the rotation center line when the exhaust linkage mechanism is rocked by the control mechanism. The exhaust mechanism includes an exhaust pivot drive unit, and the distance between the pivot drive center line of the intake pivot drive unit and the rotation center line is shorter than the distance between the pivot drive center line of the exhaust pivot drive unit and the rotation center line. When driven, the intake interlock mechanism is exhausted. With the exhaust cam shaking motion amount larger than that swing about said cam axis by the driving mechanism, is to swing the intake cam about said cam axis.

According to this, when the intake interlock mechanism and the exhaust interlock mechanism are swung by the control mechanism, the intake interlock mechanism has a pivot drive center line at a position closer to the rotation center line of the camshaft than the pivot drive center line of the exhaust interlock mechanism. The mechanism causes the intake cam and the exhaust cam to swing around the cam shaft so that the swing amount of the intake cam becomes larger than the swing amount of the exhaust cam via the intake linkage mechanism and the exhaust linkage mechanism.

Best Mode for Carrying Out the Invention Embodiments of the present invention will now be described with reference to FIGS. 1 to 14.

1, the internal combustion engine E to which this invention was applied is mounted in the motorcycle V as a vehicle. The motorcycle V is rotatably supported by a vehicle body frame 1 having a front frame 1a and a rear frame 1b and a head pipe 2 coupled to a front end of the front frame 1a. A handle 4 fixed to the upper end of the front fork 3, a front wheel 7 rotatably supported on the lower end of the front fork 3, a power unit U supported on the body frame 1, And a rear wheel 8 rotatably supported at the rear end of the swing arm 5 rotatably supported by the body frame 1, and the rear frame 1b and the rear end of the swing arm 5 are connected. A rear cushion 6 to be fitted and a vehicle body cover 9 covering the vehicle body frame 1.

The power unit U has a horizontally arranged internal combustion engine E having a crankshaft 15 extending in the left and right directions of the motorcycle V and a rear wheel 8 for powering the internal combustion engine E with a transmission. ) Is provided with a transmission device. The internal combustion engine (E) includes a crankcase (10) which forms a crank chamber in which the crankshaft (15) is accommodated, and also serves as a transmission case, a cylinder (11) coupled to the crankcase (10) and extending forward; A cylinder head 12 coupled to the front end of the cylinder 11 and a head cover 13 coupled to the front end of the cylinder head 12 are provided. The cylinder axis L1 of the cylinder 11 extends inclined slightly upward with respect to the horizontal direction toward the front (refer FIG. 1), or extends substantially parallel to a horizontal direction. Then, the rotation of the crankshaft 15 which is rotationally driven by the piston 14 (see FIG. 2) is shifted by the transmission and transmitted to the rear wheel 8, so that the rear wheel 8 is driven.

Referring to FIG. 2, the internal combustion engine E is an SOHC type air-cooled single-cylinder four-stroke internal combustion engine, and the cylinder 11 is provided with a cylinder hole 11a in which a piston 14 is fitted to reciprocate. In the cylinder head 12, a combustion chamber 16 is formed on a surface of the cylinder head 12 facing the cylinder hole 11a in the cylinder axis direction A1, and an intake port having an inlet port 17a respectively opened in the combustion chamber 16 ( 17 and an exhaust port 18 having an exhaust port 18a is formed. Moreover, the spark plug 19 which faces the combustion chamber 16 is inserted in the mounting hole 12c formed in the cylinder head 12, and is attached to the cylinder head 12. As shown in FIG. Here, the combustion chamber 16 constitutes a combustion space together with the cylinder hole 11a between the piston 14 and the cylinder head 12.

In addition, one intake valve 22 and one that is an engine valve which is supported by the cylinder head 12 so as to be reciprocally supported by the valve guides 20i and 20e and is always pressurized in the valve closing direction by the valve spring 21. Two exhaust valves 23 are provided. The intake valve 22 and the exhaust valve 23 are opened and closed by the operation valve device 40 provided in the internal combustion engine E, and the intake port 17a and the exhaust port (formed by the valve seat 24) are formed. Open and close 18a) respectively. The operation valve device 40 is disposed in the operation valve chamber 25 formed of the cylinder head 12 and the head cover 13 except for the electric motor 80 (see FIG. 5).

On the upper surface 12a, which is one side of the cylinder head 12 through which the inlet 17b of the intake port 17 opens, in order to guide air introduced from the outside into the intake port 17, the air cleaner 26 ( 1) and an intake apparatus having a throttle body 27 (see FIG. 1), the lower surface 12b being the other side of the cylinder head 12 to which the outlet 18b of the exhaust port 18 opens. The exhaust apparatus is equipped with the exhaust pipe 28 (refer FIG. 1) which guides the exhaust gas which flows out from the combustion chamber 16 through the exhaust port 18 to the exterior of the internal combustion engine E. As shown in FIG. The intake apparatus is also provided with a fuel injection valve which is a fuel supply device for supplying liquid fuel to intake air.

And the air sucked in through the air cleaner 26 and the throttle body 27 passes from the intake port 17 to the combustion chamber 16 via the intake valve 22 opened by the valve in the intake stroke which the piston 14 descends. ), And the piston 14 is pressurized in a mixed state with fuel in an ascending compression stroke. The mixer is ignited and combusted by the spark plug 19 at the end of the compression stroke, so that the piston 14 driven by the pressure of the combustion gas in the expansion stroke in which the piston 14 descends has the crankshaft 15. Drive to rotate. The gas which has already been burned is discharged from the combustion chamber 16 to the exhaust port 18 as the exhaust gas via the exhaust valve 23 which is valve-opened in the exhaust stroke in which the piston 14 rises.

3, the throttle body 27 which communicates with the air cleaner 26 at the upstream end 27a side, and communicates with the intake port 17 via the intake pipe at the downstream end 27b side, is connected to a return spring. The throttle valve 30 pressurized in the valve closing direction by the valve, the throttle control mechanism T for opening and closing the throttle valve 30 to control the opening degree, and the throttle opening degree detection means for detecting the opening degree of the throttle valve 30. 32 is installed. The throttle control mechanism T includes an electric motor 33 that is an actuator controlled by an electronic control unit (hereinafter referred to as "ECU") 92 (see FIG. 5) as a control device, and an electric motor 33. It is provided with the reduction gear train which consists of a series of gears 34 and 35 which comprise the transmission mechanism which transmits a driving force to the throttle valve 30. As shown in FIG.

Referring to FIG. 5, the ECU 92 includes an output request amount detecting unit 95 for detecting an operation amount D of a throttle grip as an output operation member operated by a driver, and a warm-up of the internal combustion engine E. Operation state detection which detects the operation state of the internal combustion engine E comprised with the engine temperature detection means 96 (for example, lubricating oil temperature detection means), the throttle opening degree detection means 32, etc. as a warm-up state detection means which detects a state. Each detection signal of the means is input. Here, the operation amount D is a required amount of engine output by the driver, and the throttle grip is an output setting means for setting the required amount.

The throttle opening degree map in which the opening degree β of the throttle valve 30 is set as a parameter is stored in the storage device of the ECU 92. This throttle opening degree map is used for the warm-up map used at the time of warm-up of the internal combustion engine E, and after the warm-up of the internal combustion engine E is completed, as shown to FIG. 4 (A), (B). It consists of a map after warm-up. And the electric motor 33 is a throttle valve according to the operation amount D detected by the output request | requirement amount detection means 95, and the actual opening degree of the throttle valve 30 detected by the throttle opening degree detection means 32. Controlled by the ECU 92 to open and close the throttle valve 30 so that the opening degree of 30 is an opening degree β set by the throttle opening degree map.

When the engine 92 detects that the engine temperature is warmed up when the engine temperature is less than the predetermined temperature by the engine temperature detecting means 96, the ECU 92 selects a map for warming up, and the engine temperature is detected by the engine temperature detecting means 96. If it is detected after warm-up that is equal to or higher than a predetermined temperature, the map for warm-up is selected. By the warm-up map, the opening degree of the throttle valve 30 is directly proportional to the operation amount D so that the opening degree of the throttle valve 30 increases with the increase of the operation amount D in the entire load region of the internal combustion engine E. The opening degree characteristic is set. Therefore, the electric motor 33 increases in response to an increase in the operation amount D, that is, the engine load, detected by the output demand amount detecting means 95, which is also a load detecting means for detecting the engine load in the entire load region. The opening degree of the throttle valve 30 is controlled to be.

On the other hand, the throttle valve 30 according to the increase of the operation amount D (engine load) in the first load region Fa from the no load to the predetermined load Da in the low load region by the warm-up map. Is increased so as to be fully opened from the idle opening degree to the predetermined load Da, and in the second load region Fb exceeding the predetermined load Da, the opening degree is such that the throttle valve 30 is fully opened regardless of the operation amount D. The property is set. Therefore, in the first load region Fa, the electric motor 33 controls the opening degree of the throttle valve 30 so as to fully open from the idle opening degree to the predetermined load Da in accordance with the increase of the operation amount D, In the two load regions Fb, the throttle valve 30 is controlled to be kept fully open. Here, the entire load region of the internal combustion engine E is divided into almost three parts between the low load region F1, the heavy load region F2, and the high load region F3 between the no load and the maximum load Db. do.

2, 5 to 7, and 12, the actuation valve device 40 intakes as an intake cam follower in contact with the valve stem 22a to open and close the intake valve 22. As shown in FIG. The main rocker arm 41, the exhaust main rocker arm 42 as the exhaust cam follower in contact with the valve stem 23a to open and close the exhaust valve 23, the intake valve 22 and the exhaust valve 23; The valve characteristic variable mechanism M which controls the valve | bulb operation characteristic including the opening / closing timing of a) and a maximum lift amount is provided.

The intake main rocker arm 41 and the exhaust main rocker arm 42 are connected to a pair of rocker shafts 43 fixed to the cam shaft holders 29 at the point portions 41a and 42a of the central portion, respectively. The intake cam 53 is contacted with the valve stems 22a and 23a by the adjustment screws 41b and 42b slidably supported and constituting the action part of one end, and the rollers 41c and 42c constituting the contact part of the other end. And the exhaust cam 54.

The valve characteristic variable mechanism M is provided with the internal mechanism accommodated in the operation valve chamber 25, and the electric motor 80 which is an electric actuator which drives the said internal mechanism as an external mechanism arrange | positioned outside the operation valve chamber 25. As shown in FIG. do. The internal mechanism is rotatably supported by the cylinder head 12, and is provided on one camshaft 50, which is rotatably driven in conjunction with the crankshaft 15, and is provided on the camshaft 50 to be integral with the camshaft 50. An intake drive cam 51 and an exhaust drive cam 52 which are rotating drive cams, link mechanisms M1i and M1e as pivotal mechanisms pivotally supported on the camshaft 50 and swingable about the camshaft 50, and a linkage mechanism An intake cam 53 and an exhaust cam 54, which are actuating valve cams connected to M1i and M1e and pivotally supported on the camshaft 50 to operate the intake main rocker arm 41 and the exhaust main rocker arm 42, respectively. And a drive mechanism M2 (see FIG. 5) having an electric motor 80 as a drive source so as to swing the link mechanisms M1i and M1e around the camshaft 50, and the drive mechanism M2 and the link. Interference between the cam shafts 50 of the link mechanisms M1i and M1e is removed in accordance with the driving force of the electric motor 80 through the mechanisms M1i and M1e. Pressing spring as a pressurizing means for pressurizing the torque around the camshaft 50 to the link mechanisms M1i and M1e in order to press the control mechanism M3 and the link mechanisms M1i and M1e to the control mechanism M3. 55 is provided.

2, 5, and 6, the camshaft 50 has a camshaft holder coupled to the cylinder head 12 and the cylinder head 12 via a pair of bearings 56 disposed at both ends thereof. 29 is rotatably supported by the crankshaft 15 by the power of the crankshaft 15 (refer to FIG. 1) which is rotatably supported by the actuating mechanism for actuating valves. It is driven to rotate at speed. The actuating mechanism for the actuating valve includes a cam sprocket 57 integrally coupled to the front end side of the left end of the camshaft 50, a drive sprocket integrally coupled to the crankshaft 15, a cam sprocket 57 and A timing chain 58 spans the drive sprocket. The transmission mechanism for the actuating valve is formed by the cylinder 11 and the cylinder head 12, and is located on the left side of the cylinder 11 and the cylinder head 12 on one side with respect to the first orthogonal plane H1. It is accommodated in a thread. And the transmission chamber 59 formed in the cylinder head 12 among the said transmission chambers is further comprised of the cam shaft 50 in the radial direction (henceforth a "diameter direction") centering on the cylinder axis L1. It is adjacent to the actuation valve chamber 25 in the direction A2 (henceforth "camshaft direction A2") of the rotation center line L2. Here, the first orthogonal plane H1 is a plane including the cylinder axis L1 and perpendicular to the reference plane H0 described later.

In the valve characteristic variable mechanism M, since the member related to the intake valve 22 and the member related to the exhaust valve 23 include members corresponding to each other, the intake drive cam 51 and the exhaust drive Since the cam 52, the link mechanisms M1i and M1e, the intake cam 53 and the exhaust cam 54 have the same basic structure, in the following description, the members related to the exhaust valve 23 will be mainly focused. It demonstrates and the member which concerns on the intake valve 22, a related description, etc. are shown in parentheses as needed.

2, 5, 8, 9, and 12, an exhaust drive cam 52 (intake drive cam 51) press-fitted to and fixed to the camshaft 50 is formed on the outer circumference over its entire circumference. It has a cam surface. The cam surface includes a base circle portion 52a (51a) which does not rock the exhaust cam 54 (intake cam 53) through a link mechanism M1e (M1i), and a link mechanism M1e (M1i). And a cam mount portion 52b (51b) which swings the exhaust cam 54 (intake cam 53) through the center of the base circle portion 52a (51a) from the rotation center line L2. Has a cross-sectional shape consisting of a circular arc with a constant radius, and the cam peak portion 52b (51b) has a cross-sectional shape that decreases after the radius from the rotation center line L2 increases in the rotation direction R1 of the camshaft 50. And, as for the base part 52a (51a), the exhaust main rocker arm 42 (intake main rocker arm 41) is the base part 54a (53a) of the exhaust cam 54 (intake cam 53). ), The swing position of the exhaust cam 54 (intake cam 53) is set so that the cam peaks 52b (51b) have an exhaust main rocker arm 42 (intake main rocker arm 41). Base base 54a (53a) and cam of exhaust cam 54 (intake cam 53) The swing position of the exhaust cam 54 (intake cam 53) is set to contact the peak 54b (53b).

The link mechanisms M1i and M1e are composed of an intake link mechanism M1i connected to the intake cam 53 and an exhaust link mechanism M1e connected to the exhaust cam 54. 5 and 6, the exhaust link mechanism M1e (intake link mechanism M1i) is pivotally supported by the camshaft 50 and is able to swing around the camshaft 50 (60e (60i)). And an exhaust sub rocker arm 66e (intake sub rocker arm 66i) pivotally supported by the holder 60e (60i) and driven by the exhaust drive cam 52 (intake drive cam 51) to swing. A connecting link 67e (67i) pivotally mounted on the exhaust sub-rocker arm 66e (intake sub-rocker arm 66i) at one end and pivotally mounted on the exhaust cam 54 (intake cam 53) at the other end; ) And a control spring 68 for pressing the exhaust sub rocker arm 66e (the intake sub rocker arm 66i) to the exhaust drive cam 52 (the intake drive cam 51).

The holder 60e (60i) supported by the camshaft 50 via the bearing 69 into which the camshaft 50 is inserted is a pair of 1st, 2nd plate 61e (61i) spaced apart in the camshaft direction A2. ), 62e (62i), and the first plate 61e (61i) and the second plate 62e (62i) are connected at predetermined intervals in the camshaft direction A2, and the exhaust sub-rocker arm 66e ( And a connecting member pivotally supporting the intake sub-rocker arm 66i). The connecting member defines a predetermined interval between both plates 61e (61i) and 62e (62i), and a support shaft for pivotally supporting the exhaust sub-rocker arm 66e (intake sub-rocker arm 66i). Also provided is a collar 63e (63i), which is also provided, and a rivet 64 inserted into the collar 63e (63i) to integrally couple both plates 61e (61i) and 62e (62i). As shown in FIGS. 6 and 8, the plates 61e (61i) and 62e (62i) are supported by the camshaft 50 so as to be able to swing on the plates 61e (61i) and 62e (62i). The mounting holes 61e3 (61i3) and 62e3 (62i3) to which the bearing 69 is mounted are formed.

Referring to FIG. 5, the first plate 61e (61i) is pivotally mounted to the exhaust control link 71e (intake control link 71i) of the control mechanism M3, and the exhaust control link 71e (intake control). Link 71i)) and the first plate 61e (61i) are connected so as to be capable of relative movement at both connecting portions 71e2 (71i2) and 61e1 (61i1). Specifically, the connection part of the 1st plate 61e (61i) as a holder side connection part in the hole of the connection part 71e2 (71i2) of the exhaust control link 71e (intake control link 71i) as a control mechanism side connection part. A connecting pin 61e1a (61i1a) press-fitted into the hole of 61e1 (61i1) is inserted so as to be relatively rotatable.

The second plate 62e (62i) also slightly opens the intake valve 22 and the exhaust valve 23 in the compression stroke at the time of starting the internal combustion engine E, thereby lowering the compression pressure to facilitate starting. The decompression cam 62e1 (62i1) (refer FIG. 8, FIG. 12) for this purpose is formed. In addition, the second plate 62e is provided with a detected portion 62e2 which is detected by the detection portion 94a of the swing position detecting means 94 (see FIG. 14). The to-be-detected part 62e2 is comprised by the tooth part which engages in the swinging direction of the 2nd plate 62e by engaging with the tooth part which comprises the detection part 94a. In addition, although not used in this embodiment, the part 62i2 corresponding to the to-be-detected part 62e2 is also provided in the 2nd plate 61i.

On the collar 63e (63i), the movable side which supports the 1st spring support part 76 which supports the one end part of the control spring 68 which consists of a compression coil spring, and the one end part of the pressurizing spring 55 which consists of a compression coil spring. The spring support 78 is integrally formed and installed. Both spring supporting portions 76, 78 are disposed adjacent to the point portion 66ea (66ia) of the exhaust sub-rocker arm 66e (intake sub-rocker arm 66i) in the camshaft direction A2 and at the same time the collar 63e. 63i), spaced apart in the circumferential direction (see FIG. 6).

In the collar 63e 63i, the convex portions 63e1 63i1 fitted to the holes 62e4 (62i4) formed in the second plate 62e (62i) are exhaust sub-rocker arms 66e ( The intake sub-rocker arm 66i) is formed at a position away from the swinging center line L3e (L3i). The convex portions 63e1 (63i1) and the holes 62e4 (62i4) rotate relative to the swing centerline L3e (L3i) between the second plate 62e (62i) and the collar 63e (63i). Configure the engaging portion to prevent the. By this engagement part, the pair of spring support parts 76 and 78 is provided, and the collar 63e (63i) by which the torque of the same direction by the spring force of the control spring 68 and the pressurizing spring 55 acts. ) Is prevented from rotating relative to the first and second plates 61e (61i) and 62e (62i), so that the pressure spring 55 causes the circumference of the camshaft 50 to the link mechanisms M1i and M1e. The torque applying action and the pressing action to the exhaust drive cam 52 (intake drive cam 51) by the control spring 68 are reliably performed.

2, 5, 6, 8, 9, and 12, in the camshaft direction A2, the exhaust cam 54 (intake cam 53) and the exhaust drive cam 52 (intake drive cam). Exhaust sub-rocker arm 66e (intake sub-rocker arm 66i) disposed between the first and second plates 61e (61i, 62e (62i)) together with the exhaust drive cam ( It contacts the exhaust drive cam 52 (intake drive cam 51) in the roller 66eb (66ib) as a contact part which contacts 52 (intake drive cam 51), and the branch part 66ea (66ia) of one end part. Pivotally supported by the collar 63e (63i) at the end) and fixed to one end of the connection link 67e (67i) at the other end connection portion 66ec (66ic). do. Therefore, the exhaust sub rocker arm 66e (the intake sub rocker arm 66i) has the collar 63e (63i) by rotating the exhaust drive cam 52 (intake drive cam 51) together with the camshaft 50. Rotate around the swing center.

The exhaust cam 54 (intake cam 53) pivotally supported by the connecting pin 73 fixed to the other end of the connecting link 67e (67i) is supported by the cam shaft 50 through the bearing 44. It consists of the oscillation cam which can rock about the camshaft 50, and a cam surface is formed in a part of the outer peripheral surface. The cam surface presses down the base end portions 54a (53a) and the exhaust valve 23 (intake valve 22) for holding the exhaust valve 23 (intake valve 22) in the valve open state. It consists of the cam peak part 54b (53b) which opens. The base circle part 54a (53a) has the cross-sectional shape which consists of a circular arc with a constant radius from the rotation center line L2, and the cam peak part 54b (53b) has a camshaft 50 with the radius from the rotation center line L2. It has a cross-sectional shape which increases in the half rotation direction R2 (rotation direction R1) of (). Therefore, the cam peak portion 54b (53b) of the exhaust cam 54 (intake cam 53) gradually becomes exhaust valve 23 (intake valve 22) in the half rotation direction R2 (rotation direction R1). The lift amount of)) increases.

The exhaust cam 54 (intake cam 53) is the same as the exhaust link mechanism M1e (intake link mechanism M1i) by the driving force of the drive mechanism M2 transmitted via the control mechanism M3. The exhaust sub-rocker arm 66e (intake sub-rocker arm 66i) which is rocked about the camshaft 50 by the amount of rocking, and rocked by the exhaust-drive cam 52 (intake drive cam 51). It swings about the camshaft 50 by this. And the exhaust cam 54 (intake cam 53) oscillating with respect to the camshaft 50 oscillates the exhaust main rocker arm 42 (intake main rocker arm 41), and the exhaust valve 23 (intake valve) (22))) to open and close. Therefore, the exhaust cam 54 (intake cam 53) connects the holder 60e (60i), the exhaust sub rocker arm 66e (intake sub rocker arm 66i) and the connecting link 67e (67i). It is oscillated by the driving force of the driving mechanism M2 which is sequentially transmitted, and is also sequentially transmitted through the exhaust sub-rocker arm 66e (intake sub-rocker arm 66i) and the connecting link 67e (67i). It is oscillated by the driving force of the exhaust drive cam 52 (intake drive cam 51).

A control spring for generating a spring force for pressing the roller 66eb (66ib) of the exhaust sub rocker arm 66e (intake sub rocker arm 66i) to the exhaust drive cam 52 (intake drive cam 51) ( 68 is disposed between the collar 63e (63i) and the exhaust cam 54, in the circumferential direction of the camshaft 50 in accordance with the swing of the exhaust sub-rocker arm 66e (intake sub-rocker arm 66i). It is flexible. The other end of the control spring 68, one end of which is supported by the first spring support 76, is provided with a second spring support provided on a shelf-like protrusion integrally formed on the exhaust cam 54 (intake cam 53). 77).

The pressure spring 55 which always exerts a spring force for exerting a torque in one direction in the swinging direction to the exhaust link mechanism M1e (intake link mechanism M1i) has a holder 60e (60i). ), And the other end is supported by the fixed side spring support 79 provided on the camshaft holder 29, which is a fixed member fixed to the cylinder head 12.

The spring force of the pressurizing spring 55 which presses the exhaust link mechanism M1e (intake link mechanism M1i) to the cylinder 11 side acts directly on the holder 60e (60i) to give the holder 60e (60i). ) Is pressed in the direction toward the cylinder 11, and the torque acting on the holder 60e (60i) by the spring force is directed to the one direction. The one direction is an exhaust valve 23 (intake valve 22) when the exhaust cam 54 (intake cam 53) opens the exhaust valve 23 (intake valve 22). Is set in the same direction as the torque acting on the exhaust cam 54 (intake cam 53) by the reaction force acting on the exhaust cam 54 (intake cam 53). Therefore, the spring force of the pressurizing spring 55 always connects the connecting portion 61e1 (61i1) to the connecting portion 71e2 (71i2) in the swinging direction, and is connected from the exhaust cam 54 (intake cam 53). Based on the torque acting on the holder 60e (60i) via the link 67e (67i) and the exhaust sub-rocker arm 66e (intake sub-rocker arm 66i), the reaction force is connected to the connection portion 61e1 (61i1). ) Is pressed in the swinging direction to the connecting portion 71e2 (71i2).

Then, by the pressing spring 55, at each of the connecting portions 71e2 (71i2) and 61e1 (61i1) where there is a slight gap due to pivot mounting, the one connecting portion 61e1 (61i1) is connected to the other connecting portion 71e2. Since 71i2 is always pressed in the swinging direction, when the first plate 61e (61i) is rocked by the exhaust control link 71e (intake control link 71i), the connection portion 71e2 (71i2) And the influence of the gap (gap) between the connecting portion 61e1 (61i1) are eliminated, so that the movement of the exhaust control link 71e (intake control link 71i) is transmitted to the holder 60e (60i) with high precision. .

2, 5, and 12, the control mechanism M3 links the motion of the control shaft 70 with a cylindrical control shaft 70 as a control member driven by the drive mechanism M2. Control links 71i and 71e which are transmitted to the mechanisms M1i and M1e and swing the link mechanisms M1i and M1e around the camshaft 50 are provided.

The control shaft 70 is movable in a direction parallel to the cylinder axis L1, and thus includes a rotation center line L2 of the camshaft 50 and is parallel to the reference plane H0 parallel to the cylinder axis L1. It can be moved in parallel with respect to it.

The control links 71i and 71e consist of the intake control link 71i and the exhaust control link 71e. The intake control link 71i is pivotally mounted to the control shaft 70 by the connecting portion 71i1 as the first intake connecting portion, and the first plate 61i of the intake link mechanism M1i by the connecting portion 71i2 as the second intake connecting portion. Is pivotally mounted on the connecting portion 61i1. The exhaust control link 71e is pivotally mounted to the control shaft 70 by the connection portion 71e1 as the first exhaust connection portion, and the first plate 61e of the exhaust link mechanism M1e by the connection portion 71e2 as the second exhaust connection portion. Is pivotally mounted on the connecting portion 61e1. The connecting portion 71i1 of the intake control link 71i and the connecting portion 70a of the control shaft 70 are each connected to the hole of the connecting portion 71e1 of the exhaust control link 71e and fixed to one connecting pin 71e3. ) Is pivotally supported by the connecting pin 71e3, and the two-shaped connecting parts 71i2 and 71e2 are respectively connected to the connecting pins 61i1a and 61e1a of the connecting parts 71i2 and 71e2. This hole is inserted in such a way as to be relatively rotatable and pivotally supported by the connecting pins 61i1a and 61e1a. Since the spring force of the pressing spring is always pressed to the connecting portion 70a at each of the connecting portions 71e1 (71i1) and 70a where there is a slight gap due to the pivot mounting, the connecting portion 71e1 (71i1), The influence of the gap (gap) between the connecting portion 71e1 (71i1) and the connecting portion 70a is eliminated, so that the movement of the control shaft 70 is precisely performed on the exhaust control link 71e (intake control link 71i). Delivered.

And the pivot drive center line L4i (refer FIG. 2, FIG. 12) of the connection part 71i1, and the pivot drive center line L4e (refer FIG. 2, FIG. 12) of the connection part 71e1 are the connection part of the control shaft 70. FIG. A common pivot drive centerline is formed at 70a and rotated in a state of being biased at a predetermined distance e by a predetermined distance to the exhaust side that is one side with respect to the reference plane H0 (see FIGS. 2 and 7). Disposed parallel to the center line L2, the pivot drive centerline L5i (see FIGS. 2 and 12) of the connection portion 71i2 is disposed parallel to the rotation centerline L2 on the exhaust side, and The pivot drive center line L5e (refer FIG. 2, FIG. 12) is arrange | positioned in parallel with the rotation center line L2 at the intake side which is the other side with respect to the reference plane H0. Therefore, as shown in FIG. 7, the central axis L6 of the control shaft 70 is parallel to the cylinder axis L1 and is biased by the amount of bias e toward the exhaust side with respect to the reference plane H0. have. Here, the intake side is a side where the intake valve 22 is arranged with respect to the reference plane H0, and the exhaust side is a side where the exhaust valve 23 is arranged with respect to the reference plane H0.

Moreover, the link length of the intake control link 71i which is the distance between both pivot drive centerlines L4i and L5i is set longer than the link length of the exhaust control link 71e which is the distance between both pivot drive centerlines L4e and L5e. . Both pivot drive centerlines L5i and L5e are arranged equidistant from the rotation centerline L2 on the same circumferential surface from the rotation centerline L2 around the camshaft 50, and simultaneously include the rotation centerline L2. The control shaft 70 and the pivot drive centerlines L4i and L4e are disposed on the side of the second orthogonal plane H2 orthogonal to the reference plane H0. The pivot drive center line L5i is located closer to the second orthogonal plane H2 than the pivot drive centerline L5e.

Therefore, the pivot drive centerlines L4i and L4e, which are common pivot drive centerlines, are biased toward the exhaust side with a predetermined bias amount e relative to the reference plane H0, or the link length of the intake control link 71i is The swing amount of the pivot drive centerline L5i around the camshaft 50 with respect to the movement amount of the control shaft 70 driven by the drive mechanism M2 by being set longer than the link length of the exhaust control link 71e. Therefore, the swing amounts of the intake link mechanism M1i and the intake cam 53 are larger than the swing amounts of the exhaust link mechanism M1e and the exhaust cam 54.

6 and 10, the drive mechanism M2 for driving the control shaft 70 rotates the reversely rotatable electric motor 80 and the electric motor 80 mounted on the head cover 13. The transmission mechanism M4 which transmits to the control shaft 70 is provided. And the control mechanism M3 and the drive mechanism M2 are arrange | positioned on the opposite side to the cylinder 11 and the combustion chamber 16 with respect to the 2nd orthogonal plane H2.

The electric motor 80 has a cylindrical main body 80a having a central axis parallel to the cylinder axis L1 and a heat generating part such as a coil part and an output shaft extending parallel to the cylinder axis L1 ( 80b). The electric motor 80 is arrange | positioned outward in the radial direction of the operation valve chamber 25 with respect to the cylinder head 12 and the head cover 13. And the transmission chamber 59 is arrange | positioned at the left side with respect to the 1st orthogonal plane H1, and the main body 80a and the spark plug 19 are arrange | positioned at the other side with respect to the 1st orthogonal plane H1. do. In the main body 80a, a through hole 80a2 is formed in the to-be-mounted portion 80a1 which protrudes in the radial direction to the head cover 13 and is coupled to the mounting portion 13a formed in the sunshade shape, and the output shaft 80b is It penetrates the through hole 80a2 and protrudes out of the main body 80a to extend into the operation valve chamber 25. The main body 80a is disposed at a position where the whole body is covered by the mounting portion as seen from the head cover 13 side in the cylinder axis direction A1 or from the front of the head cover 13 (see FIG. 10). ).

2, 5, and 10, in the operation valve chamber 25, the transmission mechanism M4 disposed between the camshaft holder 29 and the head cover 13 in the cylinder axis direction A1 is A reduction gear 81 engaged with the drive gear 80b1 formed in the output shaft 80b extending through the head cover 13 and into the actuating valve chamber 25; 12 is composed of an output gear 82 rotatably supported by a camshaft holder 29. The reduction gear 81 is rotatably supported by the support shaft 84 supported by the head cover 13 and the cover 83 covering the opening 13c formed in the head cover 13, and the drive gear 80b1. And a large gear 81a meshing with and a small gear 81b meshing with the output gear 82. The output gear 82 has a cylindrical boss portion 82a rotatably supported via a bearing 89 in a support cylinder 88 coupled to a camshaft holder 29 by bolts.

The output gear 82 and the control shaft 70 are feed screws as a motion conversion mechanism for converting the rotational motion of the output gear 82 into a linear reciprocating motion parallel to the cylinder axis L1 of the control shaft 70. The drive is connected via a mechanism. The feed screw mechanism includes a female screw portion 82b made of a trapezoidal screw formed on the inner circumferential surface of the boss portion 82a, and a male screw portion made of a trapezoidal screw formed on the outer circumferential surface of the control shaft 70 and screwed to the male screw portion 70b. 70b). The control shaft 70 is slidably fitted to the outer circumference of the guide shaft 90 fixed to the boss portion 82a and is guided in the moving direction by the guide shaft 90. The cam shaft holder 29 It passes through the through-hole 91 (refer also FIG. 7) formed in (), and can advance and retract with respect to the camshaft 50 in the cylinder axis direction A1.

Referring to FIG. 5, the electric motor 80 is controlled by an electronic control unit (hereinafter referred to as ECU) 92. Therefore, in the ECU 92, in addition to the output demand amount detecting means 95 and the engine temperature detecting means 96, a start detection for detecting the start time of the internal combustion engine E constituting the operation state detecting means. The detection signal from the means or the engine rotational speed detecting means for detecting the engine rotational speed, the holder 60e of the exhaust link mechanism M1e, and the exhaust cam 54 further oscillated by the electric motor 80. The detection signal from the rocking position detecting means 94 (for example, it is composed of a potentiometer) that detects the rocking position which is the rocking angle with respect to the camshaft 50 is input.

In the storage device of the ECU 92, a valve control map in which the swing position is set using the manipulated variable D as a parameter is stored. And ECU 92 is the actual fluctuation | variation of the operation amount D detected by the output request | requirement amount detection means 95, and the holder 60e of the exhaust link mechanism M1i detected by the swing position detection means 94. As shown in FIG. The electric motor 80 is controlled to be a swing position set by the valve control map according to the position, that is, the actual swing position of the exhaust cam 54. Therefore, when the position of the control shaft 70 driven by the electric motor 80 is changed, the exhaust link mechanism M1e (intake link mechanism M1i) and the exhaust cam 54 (intake cam 53) are changed. The swinging position, which is a rotational position relative to the camshaft 50, is changed in accordance with the operation amount D, and the valve operating characteristic of the exhaust valve 23 (intake valve 22) is changed depending on the operating state of the internal combustion engine E. Controlled.

Specifically, it is as follows.

As shown in FIG. 11, the intake valve and the exhaust valve are respectively shown as basic operating characteristics of the valve operating characteristics Ki and Ke controlled by the valve characteristic variable mechanism M which changes the opening and closing timing and the maximum lift amount. , Any intermediate valve between the maximum valve operating characteristics (Kimax, Kemax) and the minimum valve operating characteristics (Kimin, Kemin), with the maximum valve operating characteristics (Kimax, Kemax) and minimum valve operating characteristics (Kimin, Kemin) as the threshold values Opening and closing operation is possible due to the operating characteristics. Therefore, with respect to the intake valve 22, as the opening timing is continuously perceived, the closing timing is continuously advanced, the valve opening period is continuously shortened, and the rotation angle of the camshaft 50 at which the maximum lift amount is obtained ( Or the crank angle, which is the rotational position of the crankshaft 15, is continuously perceived and the maximum lift amount is continuously reduced. And simultaneously with the change of the valve operating characteristic of the intake valve 22, as for the exhaust valve 23, as the opening period is perceived continuously, a closing time is progressed continuously and a valve opening time is shortened continuously, Moreover, the rotation angle of the camshaft 50 which obtains the maximum lift amount continuously advances, and the maximum lift amount continuously becomes small.

Referring to FIG. 12, when the control shaft 70 and the intake control link 71i driven by the drive mechanism M2 occupy the first positions shown in FIGS. 12A and 12B, The maximum valve operating characteristic (Kimax) in which the opening timing of the intake valve 22 becomes the most advanced angle position θiomax, the closing timing becomes the lowest angle position θicmax, and both the valve opening period and the maximum lift amount are the maximum. ), And at the same time, the opening timing of the exhaust valve 23 becomes the most advanced position θeomax, the closing timing becomes the most angular position θecmax, and both the valve opening period and the maximum lift amount are The maximum valve operating characteristic Kemax is obtained.

12 and 13, the exhaust link mechanism M1e (intake link mechanism M1i) and the exhaust main rocker arm 42 (the exhaust valve 23 (intake valve 22) is closed). The state of the intake main rocker arm 41) is shown by solid and broken lines, and the exhaust link mechanism M1e (intake link mechanism) when the exhaust valve 23 (intake valve 22) is valve-opened at the maximum lift amount. (M1i))) and the outline of the state of the exhaust main rocker arm 42 (intake main rocker arm 41) is shown by the dashed-dotted line.

In accordance with the operating state of the internal combustion engine E, when the valve characteristic variable mechanism M shifts from the state in which the maximum valve operating characteristics Kimax and Kemax are obtained to the state in which the minimum valve operating characteristics Kimin and Kemin are obtained. The electric motor 80 rotates and drives the output gear 72, and the control shaft 70 advances toward the cam shaft 50 by the feed screw mechanism. At this time, the control shaft 70 moves the intake link mechanism M1i and the intake cam 53 around the camshaft 50 via the intake control link 71i based on the driving amount of the electric motor 80. It swings in rotation direction R1, and at the same time, the exhaust link mechanism M1e and the exhaust cam 54 are rocked about the camshaft 50 in the half rotation direction R2 via the exhaust control link 71e.

And when the control shaft 70 and the exhaust control link 71e occupy the 2nd position shown to FIG. 13 (A), (B), the opening timing of the intake valve 22 is the most perceptual position (thetaiomin). And the closing timing becomes the most advanced angle position [theta] icmin, and the minimum valve operating characteristic (Kimax) in which both the valve opening period and the maximum lift amount are minimum is obtained, and at the same time, the opening timing of the exhaust valve 23 Becomes the lowest angle position θeomin, the closing timing becomes the nearest angle position θecmin, and minimum valve operating characteristic Kemin is obtained in which both the valve opening period and the maximum lift amount are minimum.

Then, when the control shaft 70 shifts from the second position to the first position, the electric motor 80 drives the output gear 82 to rotate in the reverse direction, and the control shaft 70 is driven by the feed screw mechanism. ) Is retracted so as to be separated from the camshaft 50. At this time, the control shaft 70 swings the intake link mechanism M1i and the intake cam 53 through the intake control link 71i in the half rotation direction R2 about the cam shaft 50, and simultaneously The exhaust link mechanism M1e and the exhaust cam 54 are swung in the rotational direction R1 about the camshaft 50 via the exhaust control link 71e.

Further, when the control shaft 70 occupies a position between the first position and the second position, with respect to the exhaust valve 23 (intake valve 22), the maximum valve operating characteristic Kemax (Kimax) And the myriad of intermediate valves in which the opening timing, closing timing, valve opening duration and maximum lift amount are set to be a value between the opening timing, closing timing, valve opening period and maximum lift amount at the minimum valve operating characteristic Kemin (Kimin). Operating characteristics are obtained.

The intake valve and the exhaust valve are opened and closed by the valve characteristic variable mechanism M in an auxiliary operation characteristic, in addition to the above basic operation characteristics. Specifically, description will be made with reference to Figs. 14A and 14B to obtain the depressurization operating characteristics as the auxiliary operating characteristics. At the time of the compression stroke at the start of the start of the internal combustion engine E, the electric motor 80 drives the output gear 82 to rotate in the reverse direction, so that the control shaft 70 exceeds the first position from the camshaft 50. Occupy the decompression position, which is the position that was retracted to fall. At this time, the exhaust link mechanism M1e (intake link mechanism M1i) and the exhaust cam 54 (intake cam 53) oscillate in the rotational direction R1 (semi-rotational direction R2). The decompression unit 62e1 (62i1) of the two plates 62e (62i) is provided with a decompression unit provided near the roller 42c (41c) of the exhaust main rocker arm 42 (intake main rocker arm 41) ( 42d (41d), roller 42c (41c) falls from exhaust cam 54 (intake cam 53), and exhaust valve 23 (intake valve 22) is small. Open the valve to the decompression opening.

Referring to FIG. 11, in response to the valve operating characteristics of the intake valve 22 and the exhaust valve 23, the overlap period Pa and the ratio of the intake valve 22 and the exhaust valve 23 near the intake top dead center. The overlap period Pb changes. That is, the maximum overlap period Pax is obtained at the maximum valve operating characteristics (Kimax, Kemax), and the maximum non-overlap period Pbx is obtained at the minimum valve operating characteristics (Kimin, Kemin), and the intermediate between both valve operating characteristics is obtained. In the valve operating characteristic, as the transition from the maximum valve operating characteristic (Kimax, Kemax) to the minimum valve operating characteristic (Kimin, Kemin), the overlap period Pa decreases to zero (zero), and the non-overlap period Pb Increases from 0 (zero). Here, in the overlap period Pa, both the exhaust valve 23 and the intake valve 22 are in the valve open state near the intake top dead center, the closing timing of the exhaust valve 23 and the opening of the intake valve 22. It is the range of the crank angle (or rotation angle of a cam angle) between time periods, and the non-overlap period Pb is exhaust valve 23 and the intake valve 22 both in valve closing state, near intake top dead center, and exhaust It is the range of the crank angle (or rotation angle of the cam angle) between the closing timing of the valve 23 and the opening timing of the intake valve 22.

And when it is detected by the engine temperature detection means 96 that the engine 92 is warming up, the ECU 92 is related to the operation amount D in the entire load region of the internal combustion engine E, as shown in Fig. 4C. On the basis of the valve control map, to control the valve operating characteristics of the intake valve 22 and the exhaust valve 23 so that the overlap period Pa fixed at a predetermined amount without a maximum overlap period Pax is obtained here. The electric motor 80 is controlled. Here, at the time of warming up, the valve characteristic variable mechanism M causes the intake valve 22 and the exhaust valve 23 to open and close at maximum valve operating characteristics (Kimax, Kemax), so that the non-overlap period in the entire load region. The valve operation characteristic is controlled so that Pb is not formed.

In addition, when it is detected by the engine temperature detection means 96 that the ECU 92 is after warming up, as shown in FIG. 4D, the valve characteristic variable mechanism M is a throttle valve in the entire load region. In order to obtain the engine output according to the required amount by cooperation with the 30, the valve operation characteristic is controlled to control the engine output by controlling the overlap period Pa or the non-overlap period Pb in accordance with the operation amount D.

4 and 11, in the first load region Fa, the valve characteristic variable mechanism M reduces the overlap period Pa to 0 (zero) as the required amount increases. The overlap period Pb is increased to control the valve operating characteristics so that the maximum non-overlap period Pbx is obtained before reaching the predetermined load Da, and in the second load region Fb, in accordance with the increase in the required amount, the maximum After the non-overlap period Pb decreases from the non-overlap period Pbx to 0 (zero), the overlap period Pa increases, and the maximum overlap period Pax becomes the maximum load (maximum operation amount) Db. The valve operating characteristics are controlled to obtain. And in this actuation valve apparatus 40, the valve characteristic variable mechanism M changes the opening / closing time of the intake valve 22 and opening / closing time of the exhaust valve 23, so that the overlap period Pa and the non-overlap period Pb ), The internal EGR rate (N) is controlled.

The internal EGR rate N represents the ratio between the amount of fresh air in the combustion chamber 16 and the amount of gas already burned in the combustion chamber 16, and is defined by the following equation.

N = Vce / (Vc-Vca)

Where Vc: cylinder volume at the intake bottom dead center

        Vca: Cylinder volume when intake valve is at effective lift

        Vce: Cylinder volume when exhaust valve is at effective lift

       Effective lift amount of the intake valve: The lift amount of the intake valve at the start of the substantial inflow of new air into the combustion chamber from the intake port through the intake valve with the valve open.

       Effective lift amount of the exhaust valve: The lift amount of the exhaust valve when the gas already combusted to the exhaust port substantially exits outflow through the exhaust valve in the valve-opened state from the combustion chamber.

Therefore, the internal EGR rate (N) is the minimum internal EGR rate (Nn) obtained at the maximum overlap period Pax at the maximum valve operating characteristics (Kimax, Kemax) and the maximum at the minimum valve operating characteristics (Kimin, Kemin). In the control range defined by the maximum internal EGR rate (Nx) obtained in the non-overlap period (Pbx), as the valve operating characteristic shifts from the maximum valve operating characteristic (Kimax, Kemax) to the minimum valve operating characteristic (Kimin, Kemin) It continuously increases from the minimum internal EGR rate Nn to the maximum internal EGR rate Nx.

At the time of warming up, the valve characteristic variable mechanism M is configured such that the intake valve 22 maintains the internal EGR rate N at the minimum internal EGR rate Nn regardless of the operation amount D in the entire load region. And valve operating characteristics of the exhaust valve 23. In addition, after warming up, the valve characteristic variable mechanism M controls the overlap period Pa or the non-overlap period Pb in accordance with the operation amount D, and by the internal EGR rate N in the entire load region. Alternatively, the engine output is controlled by the amount of internal EGR defined by the internal EGR rate N. More specifically, after warming up, in the valve characteristic variable mechanism M, in the first load region Fa, the internal EGR rate N is the operation amount D from the minimum internal EGR rate Nn at no load. Increases with increasing), and controls the valve operating characteristics of the intake valve 22 and the exhaust valve 23 so that the maximum internal EGR rate Nx is obtained before reaching the predetermined load Da, and the second load region ( At Fb), the internal EGR rate N decreases from the maximum internal EGR rate Nx at the predetermined load Da with the increase of the operation amount D, and the minimum internal EGR rate at maximum load Db ( The valve operating characteristics of the intake valve 22 and the exhaust valve 23 are controlled so that Nn) is obtained.

In addition, with respect to the opening timing at which the intake valve 22 is separated from the valve seat 24 and actually opening the valve, the effective opening timing, which is the timing at which the intake valve 22 opens the valve with the effective lift amount, and the exhaust valve 23 When the effective closing time, which is the time for opening the valve by the effective lift amount, is used, the overlap period Pa and the non-overlap period Pb can be represented by the effective overlap period Pae and the effective non-overlap period Pbe. Moreover, in this embodiment, the said effective lift amount of the intake valve 22 and the exhaust valve 23 is set to the same value.

Hereinafter, control of the valve operating characteristic by the valve characteristic variable mechanism M is demonstrated using the effective non-overlap period Pbe prescribed | regulated by the effective opening time and the effective closing time. The valve characteristic variable mechanism of the intake valve 22 and the exhaust valve 23 is fixed so that both the effective overlap period Pae and the effective non-overlap period Pbe are fixed to zero (zero) in the entire load region at the time of warming up. After controlling the valve operating characteristics and warming up, in the first load region Fa, the effective non-overlap period Pbe is increased from 0 (zero) at no load to the predetermined load Da in accordance with the increase in the operation amount D. The valve operating characteristic is controlled to increase up to the maximum value at), and in the second load region Fb, the effective ratio overlap period Pbe is from the maximum value to the maximum value of the manipulated value D according to the increase of the manipulated value D. The valve operating characteristics of the intake valve 22 and the exhaust valve 23 are controlled to decrease until it becomes zero (zero) at the maximum load. In addition, in this embodiment, the rotation angle (crank angle) of the camshaft 50 in which both the effective overlap period Pae and the effective non-overlap period Pbe become zero (zero) is intake top dead center.

Then, the effective overlap period Pae and the effective non-overlap period Pbe obtained by the intake valve 22 and the exhaust valve 23 which are opened and closed at the maximum valve operating characteristics Kimak and Kemax are 0 (zero), which is the minimum value. In this case, the internal EGR rate N becomes the minimum internal EGR rate Nn, and the effective ratio overlap obtained by the intake valve 22 and the exhaust valve 23 which are opened and closed by minimum valve actuation (Kimin, Kemin) is achieved. When the period Pbe becomes the maximum value Pbex, the internal EGR rate N becomes the maximum internal EGR rate Nx.

Next, the operation and effect of the embodiment configured as described above will be described.

When warming up the internal combustion engine E, the throttle control mechanism T adjusts the opening degree of the throttle valve 30 so that the opening degree increases with the increase of the operation amount D in the entire load region of the internal combustion engine E. In addition, the valve characteristic variable mechanism M controls the valve operating characteristics of the intake valve 22 and the exhaust valve 23 so that the non-overlap period Pb is not formed in the entire load region, and thus the internal EGR rate N The internal combustion engine E is controlled in a warming-up control form such that the internal EGR ratio N is minimized in the control range of C. Thus, during warming-up, new air is supplied to the throttle valve 30 in the entire load region. The flow rate is controlled in accordance with the operation amount D and supplied to the combustion chamber 16 while the internal EGR rate N is not formed by the valve characteristic variable mechanism M, so that the non-overlap period Pb is not formed. , Compared with the case where the non-overlap period Pb is formed, to control the internal EGR rate N It is controlled so as to minimize the above, the combustibility and increase, also due to high combustion temperatures, in the entire region of a load, combustibility is improved to improve the stability of combustion, and the combustion temperature increases, the warming up of the internal combustion engine is facilitated. In addition, since the combustion temperature is increased, the warm-up of the catalyst device, which is the exhaust purification device installed in the exhaust device, is also promoted, so that the activation of the catalyst device is faster, and the exhaust purification performance is improved.

After the warm-up of the internal combustion engine E, the throttle control mechanism T opens the throttle valve 30 so as to fully open from the idle opening degree to the predetermined load Da in accordance with the increase of the operation amount D in the first load region Fa. Control the opening degree, and at the second load region Fb, the throttle valve 30 is controlled to all open, and the valve characteristic variable mechanism M is overlapped in accordance with the operation amount D in the entire load region. (Pa) or the non-overlap period Pb to control the engine output by the internal EGR rate N, and the maximum internal EGR rate Nx by the maximum non-overlap period Pbx at a predetermined load Da. The internal combustion engine E is controlled by a post-warm-up control mode that controls the valve operating characteristics so that the pumping characteristic is obtained, so that the pumping loss is further reduced in the entire load region, especially in the low load region F1, thereby improving fuel economy performance. On the other hand, in accordance with the operation amount (D) Since the engine output is controlled at the internal EGR rate N by the control of the overlap period Pa and the non-overlap period Pb so that the output is obtained, the pumping loss is reduced and the amount of NOx generated is reduced, and the predetermined load ( In Da), since the internal EGR ratio N is maximum, the generation amount of pumping loss and NOx in the low load region F1 near the predetermined load Da is greatly reduced, thereby improving fuel economy performance and exhaust purification performance.

Moreover, in the said post-warming up control form, the valve characteristic variable mechanism M has the operation amount (1) from the minimum internal EGR rate Nn in a no load in the 1st load area | region Fa. Increased with increasing D), the valve operating characteristics of the intake valve 22 and the exhaust valve 23 are controlled so that the maximum internal EGR rate Nx is obtained at the predetermined load Da, and the second load region Fb. ), The internal EGR rate N decreases from the maximum internal EGR rate Nx at the predetermined load Da with the increase of the operation amount D, and the minimum internal EGR rate Nn at the maximum load Db. The valve operating characteristics of the intake valve 22 and the exhaust valve 23 are controlled to obtain. As a result, in the first load region Fa, since the opening degree of the throttle valve 30 is large, the internal EGR ratio N is increased to suppress the inflow of new air into the combustion chamber 16, so that the pumping loss is reduced. The amount of NOx generated decreases, and in the second load region Fb, as the operation amount D increases, the non-overlap period Pb decreases and the internal EGR rate N decreases, so that the combustion chamber 16 Since the amount of new air supplied increases, the closer the predetermined load Da is, the larger the internal EGR ratio N is, so that the pumping loss is reduced and the amount of NOx generated is reduced, thereby improving fuel economy performance and exhaust purification performance. This improves and a large engine output is obtained in the high load area F3, and the required engine output according to the required amount is secured.

In the valve characteristic variable mechanism M, the maximum internal EGR rate Nx, or the maximum non-overlap period Pbx and the maximum effective ratio overlap in the load region smaller than the predetermined load Da in the first load region Fa. By controlling the valve operating characteristics so that the period Pbex is obtained, the pumping loss in the first load region Fa is further reduced, thereby improving fuel economy performance and improving exhaust purification performance.

The valve characteristic variable mechanism M is effective from a state where the reduction in the overlap period Pa, the increase in the non-overlap period Pb, the effective overlap period Pae, and the effective non-overlap Pbe are all 0 (zero). In response to an increase in the non-overlap period Pbe, or an increase in the internal EGR rate N, by controlling the valve operating characteristic so that the maximum lift amount of the intake valve 22 decreases, when the overlap period Pa is large, the non-overlap When the period Pb is small, when the effective ratio overlap period Pbe is small, or when the internal EGR ratio N is small, the maximum lift amount of the intake valve 22 is large, so that the pumping loss is reduced, and In the vicinity of the predetermined load Da, when the overlap period Pa is small, when the non-overlap period Pb is large, when the effective non-overlap period Pbe is large, or when the internal EGR ratio N is large, the internal Since the EGR ratio N is large, the pumping loss is reduced, so the pumping loss in the first load region Fa and around the predetermined load Da is reduced. Reduced by, thus increasing fuel efficiency.

At the same time, the valve characteristic variable mechanism M is in a state where the reduction in the overlap period Pa, the increase in the non-overlap period Pb, the effective overlap period Pae and the effective non-overlap period Pbe are all 0 (zero). When the overlap period Pa is large by controlling the valve operating characteristic so that the maximum lift amount of the exhaust valve 23 decreases in accordance with an increase in the effective ratio overlap period Pbe from or an increase in the internal EGR rate N. When the non-overlap period Pb is small, the effective non-overlap period Pbe is small, or when the internal EGR rate N is small, the maximum lift amount of the exhaust valve 23 is large, so that the pumping loss is reduced. Further, in the vicinity of the predetermined load Da, when the overlap period Pa is small, when the non-overlap period Pb is large, when the effective non-overlap period Pbe is large, or when the internal EGR rate N is large, At this time, since the internal EGR ratio N is large, the pumping loss decreases, and therefore, in the vicinity of the first load region Fa and the predetermined load Da, Pumping loss is reduced to, and even improved fuel economy performance points.

The valve characteristic variable mechanism M controls the valve operating characteristics so that the effective overlap period Pae and the effective non-overlap period Pbe become zero in the maximum overlap period Pax or the minimum internal EGR rate Nn. In the control range of the internal EGR rate N, on the basis of the timing at which the outflow of the already burned gas from the combustion chamber 16 is substantially stopped, and the inflow of new air into the combustion chamber 16 is substantially started. Since the control of the internal EGR rate N is started, the control accuracy of the internal EGR rate N is increased and the control range can be enlarged, so that the control or effective non-overlap period of the internal EGR rate N ( The control accuracy of the engine output by the control of Pbe can be improved.

In the valve characteristic variable mechanism M, the control mechanism M3 increases the internal EGR rate N by decreasing the overlap period Pa, increasing the non-overlap period Pb or the effective non-overlap period Pbe. When it is driven by the drive mechanism M2 in the direction, the perceived amount of the opening timing of the intake valve 22 by the intake link mechanism M1i is determined by the closing timing of the exhaust valve 23 by the exhaust link mechanism M1e. By connecting the drive mechanism M2 and each of the link mechanisms M1i and M1e so as to be larger than the advance amount, the valve characteristic variable mechanism M increases the overlap period Pa in the direction in which the internal EGR rate N increases. When decreasing, increasing the non-overlap period Pb, or increasing the effective non-overlap period Pbe, the perception amount of the opening timing of the intake valve 22 is larger than the advance amount of the closing timing of the exhaust valve 23. Since it becomes large, the closing timing of the exhaust valve 23 advances, and the pressure of the already burned gas remaining in the combustion chamber 16 is high. When the intake valve 22 is closed, the intake valve 22 is a valve when the pressure in the combustion chamber 16 is lower than that in the case where the perceptual amount at the time of valve opening of the intake valve 22 is less than or equal to the advance amount of the closing timing of the exhaust valve 23. Since the opening starts, the backflow of the intake air is prevented or suppressed.

The pivot drive center line L4i and the pivot drive center line L4e are disposed on the exhaust side with respect to the reference plane H0 and arranged in parallel to the rotation center line L2, the pivot drive centerline L5i is disposed on the exhaust side, The pivot drive center line L5e is disposed on the intake side, so that when the control shaft 70 moves, the intake link mechanism M1i swings about the camshaft 50 with a larger swing amount than the exhaust link mechanism M1e. Since the valve operating characteristic in which the perception amount of the opening timing of the intake valve 22 is larger than the advance amount of the closing timing of the exhaust valve 23 is obtained, the control mechanism M3 is provided to the intake link mechanism M1i and the exhaust link mechanism M1e. After the control shaft 70 of) is shared, the arrangement of the pivot drive centerline L4i, pivot drive centerline L4e, pivot drive centerline L5i and pivot drive centerline L5e with respect to the reference plane H0 As a result, the valve characteristic variable mechanism M is downsized, and its structure is simplified.

The pivot drive centerline L4i and the pivot drive centerline L4e are arranged parallel to the rotation centerline L2, the pivot drive centerline L5i is disposed on the exhaust side, and the pivot drive centerline L5e is disposed on the intake side. Since the link length of the intake control link 71i is longer than the link length of the exhaust control link 71e, when the control shaft 70 is moved, the intake link mechanism M1i is larger than the exhaust link mechanism M1e. The valve operating characteristic is obtained by swinging around the camshaft 50 with a large amount of swing and increasing the amount of perception at the opening timing of the intake valve 22 to be greater than the amount of advance at the closing timing of the exhaust valve 23. Therefore, the intake link mechanism M1i ), And after the control shaft 70 of the control mechanism M3 is shared by the exhaust link mechanism M1e, the pivot drive centerline L5i and the pivot drive centerline L5e are divided into both sides of the reference plane H0. And the link length of the intake control link 71i is the link of the exhaust control link 71e. Since it is longer than the length, the valve characteristic variable mechanism is downsized, and the structure is simplified.

In addition, the pivot drive centerline L4i and the pivot drive centerline L4e constitute a common pivot drive centerline, whereby the valve characteristic variable mechanism M is further miniaturized, and the structure thereof is further simplified.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment which changed the structure of one part of embodiment mentioned above is demonstrated about the changed structure.

6 and 12, the exhaust link mechanism M1e (intake link mechanism M1i) is a control in which the exhaust link mechanism M1e (intake link mechanism M1i) is driven by the drive mechanism M2. When oscillated by the exhaust control link 71e (intake control link 71i) which transmits the movement of the shaft 70, it has a pivot drive centerline which oscillates about the rotation center line L2 of the camshaft 50. FIG. Since the exhaust pivot drive unit (intake pivot drive unit) is provided, the distance between the pivot drive center line and the rotation center line L2 of the intake pivot drive unit is shorter than the distance between the pivot drive center line and the rotation center line L2 of the exhaust pivot drive unit. Therefore, when the control shaft 70 and the exhaust control link 71e (intake control link 71i) are driven by the drive mechanism M2, the intake link mechanism M1i is driven by the exhaust link mechanism M1e. Intake air with a larger swing amount than the exhaust cam 54 swinging around the camshaft 50 To 53 it is also possible to swing about the camshaft (50).

Here, the intake pivot drive part includes a connection portion 61i1 of the first plate 61i, a point portion 66ia of the intake sub-rocker arm 66i, and a support portion 63i2 of the collar 63i (see FIG. 6). It is comprised by each. In addition, the pivot drive centerline of each said intake pivot drive part is pivot drive centerline L5i, and rocking centerline L3i.

Similarly, the exhaust pivot drive part of the connection part 61e1 of the 1st plate 61e, the point part 66ea of the intake sub rocker arm 66e, and the support part 63e2 (refer FIG. 6) of the collar 63e, It is composed by each. Moreover, the pivot drive center line of each said exhaust pivot drive part is pivot drive center line L5e, and rocking center line L3e.

Then, the distance between the pivot drive center line L5i and the rotation center line L2 is set to be shorter than the distance between the pivot drive center line L5e and the rotation center line L2, or the swing center line L3i and the rotation center line L2. The distance is set shorter than the distance between the swing center line L3e and the rotation center line L2.

Thereby, when the intake link mechanism M1i and the exhaust link mechanism M1e are rocked by the control mechanism M3, the intake pivot drive portion of the intake link mechanism M1i is the above-mentioned of the exhaust link mechanism M1e. The control mechanism M3 has the intake cam (L3i, L3i) at the position closer to the rotation centerline L2 of the camshaft 50 than the pivot drive centerlines L5e and L3e of the exhaust pivot drive unit. The camshaft 50 is made so that the fluctuation amount of the intake cam 53 becomes larger than the fluctuation amount of the exhaust cam 54 through the intake link mechanism M1i and the exhaust link mechanism M1e. Swing around the center. As a result, the structure of the valve characteristic variable mechanism M for obtaining the valve operating characteristic by which the perception amount of the opening timing of the intake valve 22 becomes larger than the advance amount of the closing timing of the exhaust valve 23 is simplified.

The predetermined load Da may be a load in the heavy load region F2. The fuel supply device may be a fuel injection valve for injecting fuel directly into the combustion chamber.

The internal combustion engine may be a multi-cylinder internal combustion engine. The internal combustion engine may include a plurality of intake valves and one or a plurality of exhaust valves in one cylinder, or an internal combustion engine in which a plurality of exhaust valves and one or a plurality of intake valves are provided in one cylinder.

In the predetermined load Da and the second load region Fb, the opening degree of the throttle valve 30 may be almost full open, and also in the maximum overlap period Pax or the minimum internal EGR rate Nn, the effective overlap period (Pae) and the effective ratio overlap period Pbe may be almost zero, and at the time of warming up, the internal EGR rate N may be almost minimum in the entire load region. Here, "almost" means that when the opening degree of the throttle valve 30 is full open, when the effective overlap period Pae and the effective non-overlap period Pbe are 0, the internal EGR ratio N is minimum, respectively. As compared to the case, it means a range in which there is no significant difference with respect to the effect.

According to invention of Claim 1, there are the following effects. That is, when the valve characteristic variable mechanism controls the overlap period and the non-overlap period in the direction in which the internal EGR rate increases, the intake valve starts valve opening with a low pressure in the combustion chamber, so that the reverse flow of the intake air is prevented or suppressed. .

According to the invention described in claim 2, in addition to the effects of the invention described in the recited claims, the following effects are obtained. That is, after the control member of the control mechanism is shared between the intake interlock mechanism and the exhaust interlock mechanism, the pivot drive center line of the first intake connection portion, the pivot drive center line of the first exhaust connection portion, the pivot drive center line of the second intake connection portion, and the second exhaust By arranging the pivot drive centerline of the connection portion with respect to the reference plane, the valve characteristic variable mechanism for obtaining the valve operating characteristic in which the amount of perception at the opening timing of the intake valve is larger than the amount of advance at the closing timing of the exhaust valve is miniaturized. It is simplified.

According to the invention described in claim 3, in addition to the effects of the invention described in the recited claims, the following effects are obtained. That is, after the control member of the control mechanism is shared between the intake interlocking mechanism and the exhaust interlocking mechanism, the pivot drive centerline of the second intake connection portion and the pivot drive centerline of the second exhaust connection portion are divided and arranged on both sides of the reference plane, Since the link length of the control link is longer than the link length of the exhaust control link, the valve characteristic variable mechanism for obtaining a valve operating characteristic in which the amount of perception at the opening timing of the intake valve is larger than the amount of advance at the closing timing of the exhaust valve is miniaturized, and its structure Is simplified.

According to the invention set forth in claim 4, in addition to the effects of the invention set forth in the recited claims, the following effects are obtained. That is, since the distance between the pivot drive center line of the intake pivot drive unit of the intake interlock mechanism and the rotation center line of the cam shaft is shorter than the distance between the pivot drive center line of the exhaust pivot drive unit of the exhaust interlock mechanism and the rotation center line of the cam shaft, the perception of the timing of opening the intake valve The structure of the valve characteristic variable mechanism for obtaining the valve operation characteristic whose quantity becomes larger than the advance amount of the closing timing of an exhaust valve is simplified.

1 is a schematic right side view of a motorcycle equipped with an internal combustion engine of the present invention.

FIG. 2 is a cross-sectional view of the internal combustion engine of FIG. 1 viewed in the direction of the arrow II-II of FIG. 6, and partially in cross section along the central axis of the valve stem of the intake valve and exhaust valve and the central axis of the control shaft. to be.

3 is a schematic view of the throttle body of the internal combustion engine of FIG.

FIG. 4 illustrates a control form in the control of the internal combustion engine of FIG. 1, (A) shows a map for warming up the throttle opening degree map, and (B) shows a map for warming up the throttle opening degree map. , (C) is a diagram showing a control form of an overlap period and a non-overlap period at the time of warming up, and (D) is a diagram showing a control form of an overlap period and a non-overlap period after warming up.

FIG. 5 is a cross-sectional view of the internal combustion engine of FIG. 1 viewed in the direction of arrow Va-Va of FIG. 10, and is partially a cross-sectional view of arrow Va-Vb of FIG. 10.

FIG. 6 is a cross-sectional view seen from the direction of the arrow VI-VI of FIG. 2 of the actuating valve device, with the head cover removed, in the internal combustion engine of FIG. Drawing.

FIG. 7 is a view of the camshaft holder attached to the cylinder head, seen from the head cover side along the cylinder axis, in the internal combustion engine of FIG.

8 is a view of the exhaust drive cam of the valve characteristic variable mechanism from the camshaft direction in the operating valve device of the internal combustion engine of FIG. 1, and (B) is an exhaust link mechanism and exhaust of the valve characteristic variable mechanism. It is a figure which shows the cam in the state which pivotally driven appropriately.

(A) is sectional drawing seen from the IXA arrow direction of FIG. 8, (B) is sectional drawing seen from the IXB arrow direction of FIG. 8, (C) is sectional drawing seen from the IXC arrow direction of FIG. , (D) is a figure seen from the arrow direction of IXD of FIG.

10 is a view of the head cover along the cylinder axis from the front in the internal combustion engine of FIG. 1 and partially broken, showing the drive mechanism of the valve characteristic variable mechanism.

It is a figure explaining the valve | operation characteristic of the intake valve and exhaust valve by the operation valve apparatus of the internal combustion engine of FIG.

12 is an explanatory view of the main part of the valve characteristic variable mechanism when the maximum valve operating characteristic is obtained for the intake valve in the operating valve device of the internal combustion engine of FIG. 1, and (B) is an exhaust valve. It is explanatory drawing of the principal part of the valve characteristic variable mechanism when the maximum valve operating characteristic is acquired, and it is a figure corresponding to the principal part enlarged view of FIG.

FIG. 13A is a diagram corresponding to FIG. 12A when the minimum valve operating characteristic is obtained for the intake valve, and FIG. 13B is a view when the minimum valve operating characteristic is obtained for the exhaust valve. It is a figure corresponding to FIG. 12 (B).

Fig. 14A is a diagram corresponding to Fig. 12A when the decompression operation characteristic is obtained with respect to the intake valve, and Fig. 12B is a diagram with Fig. 12 when the decompression operation characteristic is obtained with respect to the exhaust valve. It is a figure corresponding to (B).

<Description of the symbols for the main parts of the drawings>

1: body frame 2: head pipe

3: front fork 4: handle

5: Swing arm 6: Rear cushion

7: front wheel 8: rear wheel

9: body cover 10: crankcase

11: cylinder 12: cylinder head

13: Head cover 14: piston

15: crankshaft 16: combustion chamber

17: intake port 18: exhaust port

19: Spark plug 20i, 20e: Valve guide

21: valve spring 22: intake valve

23: exhaust valve 24: valve seat

25: operation valve chamber 26: air cleaner

27: throttle body 28: exhaust pipe

29: camshaft holder 30: throttle valve

32: Throttle opening degree detection means 33: Electric motor

34, 35: gear 40: operating valve device

41, 42: Main rocker arm 43: Rocker shaft

44: bearing 50: camshaft

51, 52: drive cam 53: intake cam

54: exhaust cam 55: pressure spring

56: bearing 57: cam sprocket

59: Electric room 60e, 60i holder

61e, 61i, 62e, 62i: Plate 63e, 63i: Color

64 rivet 66i, 66e: sub-locker arm

67e, 67i: connection link 68: control spring

69: bearing 70: control shaft

71i, 71e: Control link 72, 73: Connection pin

76, 77, 78, 79: spring support 76a, 77a, 78a, 79a: spring guide

80: electric motor 80b: output shaft

81: reduction gear 82: output gear

83: cover 84: support shaft

88: support container 89: bearing

90: guide shaft 91: through hole

92: ECU 94: Rotational position detecting means

95: output demand amount detection means 96: engine temperature detection means

E: Internal combustion engine V: Motorcycle

U: Power unit L1: Cylinder axis

L2: Rotational Centerline L3i, L3e: Rotational Centerline

L4i, L4e, L5i, L5e: Pivot Drive Center Line L6: Center Axis

A1: Cylinder axis direction A2: Cam axis direction

T: Throttle control mechanism D: Operation amount

Da: predetermined load Db: maximum load

Fa, Fb: Load area e: Deviation amount

M: Valve characteristic variable mechanism M1i, M1e: Link mechanism

M2: Drive Mechanism M3: Control Mechanism

M4: Delivery Mechanism H0: Reference Plane

H1, H2: Orthogonal plane R1: Direction of rotation

R2: Anti-rotation direction Kimax, Kemax: Maximum valve operating characteristics

Kimin, Kemin: Minimum valve operating characteristic β: Opening degree

θiomax, θicmin, θeomax, θecmin: Position

θicmax, θiomin, θecmax, θeomin: Maximum angle position

Pa: Overlap Period Pb: Non-Overlap Period

Pae: Valid overlap period Pbe: Valid non overlap period

N: Internal EGR Rate Nn: Minimum Internal EGR Rate

Nx: Maximum Internal EGR Rate

Claims (4)

And a valve characteristic variable mechanism for controlling the valve operating characteristics of the intake valve and the exhaust valve, respectively, wherein the valve characteristic variable mechanism controls the overlap period and the non-overlap period by changing the opening and closing times of the intake valve and the exhaust valve. In the operation valve device of an internal combustion engine whose EGR rate is controlled, The valve characteristic variable mechanism includes a camshaft rotating in conjunction with a crankshaft of the internal combustion engine, an intake interlocking mechanism connected to an intake cam for opening and closing the intake valve in accordance with the rotation of the camshaft, and rotation of the camshaft. An exhaust interlocking mechanism connected to an exhaust cam for opening and closing the exhaust valve, a control mechanism for oscillating each of the interlocking mechanisms about the camshaft, and a drive mechanism for driving the control mechanism; When driven by the drive mechanism in the direction of increasing the internal EGR rate due to the decrease in the overlap period or the increase in the non-overlap period, the amount of perception of the opening timing of the intake valve by the intake interlock mechanism is the exhaust interlock. The drive mechanism and the respective interlocks so as to be larger than the advance amount of the closing timing of the exhaust valve by the mechanism. It operated valve system for an internal combustion engine, characterized in that connecting the sphere. 2. The control mechanism according to claim 1, wherein the control mechanism is driven by the drive mechanism and pivotally mounted to the control member at a first intake connection portion and a control member movable in a direction parallel to a reference plane including a rotation centerline of the camshaft. And an intake control link pivotally mounted to the intake interlock mechanism at a second intake connection, and an exhaust control link pivotally mounted to the control member at a first exhaust connection and pivotally mounted to the exhaust linkage at a second exhaust connection; And a pivot driving center line of the first intake connecting portion and a pivot driving center line of the first exhaust connecting portion are disposed parallel to the rotation center line on one side with respect to the reference plane, and the pivot driving center line of the second intake connecting portion is It is arrange | positioned at one side, and the pivot drive centerline of the said 2nd exhaust connection part is the other with respect to the said reference plane And the intake interlock mechanism swings around the camshaft with a larger amount of swing than the exhaust linkage mechanism when the control member is moved by being disposed on the side. 2. The control mechanism according to claim 1, wherein the control mechanism is driven by the drive mechanism and pivotally mounted to the control member at a first intake connection portion and a control member movable in a direction parallel to a reference plane including a rotation centerline of the camshaft. And an intake control link pivotally mounted to the intake interlock mechanism at a second intake connection, and an exhaust control link pivotally mounted to the control member at a first exhaust connection and pivotally mounted to the exhaust linkage at a second exhaust connection; And a pivot driving center line of the first intake connecting portion and a pivot driving center line of the first exhaust connecting portion are disposed parallel to the rotation center line, and a pivot driving center line of the second intake connecting portion is disposed on one side with respect to the reference plane. The pivot drive centerline of the second exhaust connection portion is disposed on the other side with respect to the reference plane, Since the link length of the intake control link is longer than the link length of the exhaust control link, when the control member moves, the intake interlock mechanism swings around the cam shaft with a larger amount of swing than the exhaust linkage mechanism. An operating valve device of an internal combustion engine. The intake air intake interlock mechanism according to any one of claims 1 to 3, wherein the intake interlock mechanism has a pivot drive center line that oscillates about a rotation center line of the cam shaft when the intake interlock mechanism is oscillated by the control mechanism. And an exhaust pivot drive unit having a pivot drive center line which swings about the rotation center line when the exhaust linkage mechanism is oscillated by the control mechanism. The intake pivot drive unit includes a pivot drive unit. Since the distance between the pivot drive center line and the rotation center line of is shorter than the distance between the pivot drive center line and the rotation center line of the exhaust pivot drive unit, when the control mechanism is driven by the drive mechanism, the intake interlocking mechanism The exhaust cambo oscillating about the camshaft by an interlock mechanism; Also a large shaking motion amount, operate the valve system for an internal combustion engine, comprising a step of swinging the intake cam about said cam axis.