JP4176563B2 - Variable valve mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a variable valve mechanism that changes a valve opening characteristic of a valve in accordance with an operation state of an internal combustion engine.
[0002]
[Prior art]
2. Description of the Related Art A variable valve mechanism that changes a lift amount, a working angle, and a phase of a valve that operates in accordance with an operating state of an internal combustion engine is used. Such a variable valve mechanism includes, for example, a swingable rocker lever installed between a drive cam and a roller rocker arm, and an eccentric shaft capable of changing the support point of the rocker arm, and the rotation angle of the eccentric shaft There is a variable valve mechanism that changes the valve opening characteristics of the valve by changing (see Patent Document 1).
[0003]
[Patent Document 1]
JP-A-7-63023;
[Patent Document 2]
JP-A-6-280521;
[Patent Document 3]
JP-A-8-144718;
[0004]
[Problems to be solved by the invention]
However, in the conventional variable valve mechanism described above, due to its structure, the valve opening characteristics of the valves of the plurality of cylinders are collectively changed by a single eccentric shaft, so that the valve opening characteristics of the valves of the plurality of cylinders are made uniform. It is necessary to improve the manufacturing accuracy and assembly accuracy of components. In addition, if parts are replaced for each cylinder or each valve during maintenance, there is a high possibility that the balance with other valves will be lost, so it is necessary to replace the valve system of multiple cylinders in assembly units. There is.
[0005]
The present invention has been made in view of the above-described problems, and an object thereof is to optimize errors with a simple configuration, improve the efficiency of the manufacturing process, and improve the maintainability.
[0006]
[Means for solving the problems and their functions and effects]
  In order to solve at least a part of the above-described problems, the present invention provides a variable valve mechanism that transmits rotational torque of a drive shaft to a valve and controls valve opening characteristics, and has at least one contact, Separately from the transmission mechanism that transmits rotational torque to the valve, the valve control mechanism that controls the valve opening characteristics by changing the position of the contact, and the adjustment that adjusts the position of the contact in the transmission mechanism The gist is to provide the member at the contact point.
  The variable valve mechanism of the present invention may be configured as follows, for example. That is, in the variable valve mechanism, the transmission mechanism includes a rotary cam that is driven by rotation of the drive shaft, a swing cam that swings to open the valve, the rotary cam, and the swing cam. An intermediate member that includes a first contact roller that contacts the rotating cam and a second contact roller that contacts the swing cam; a control shaft that adjusts a swing range of the swing cam; and the intermediate member; The adjustment member may be provided on at least one of the contact points in contact with the rotating cam and the swing cam.
[0007]
The adjustment member may be formed in various shapes such as a flat plate or a tapered shape with a gradually changing thickness. From the viewpoint of ease of processing, a circular flat plate is preferable, but not limited thereto. Moreover, in order to suppress wear due to sliding friction or the like, it is preferably formed of a sintered material or the like.
[0008]
The adjustment by the adjusting member may be, for example, changing the position of the contact by exchanging the size, shape, etc. of the member. It is good also as implement | achieving by adjusting the thickness of the site | part which contact | abuts to a contact by making an adjustment member into a taper shape and shifting an installation position. Although it may be installed at any contact point, it is preferable to install it at a site having a high influence on the valve opening characteristics because the adjustment accuracy is improved.
[0009]
According to the present invention, even when a variation that cannot be overlooked in the valve opening characteristics between the cylinders occurs, the adjustment member can individually absorb and optimize the error of the variable mechanism. Efficiency can be improved. In addition, during maintenance, the adjustment member can be replaced to optimize the error and variation in the valve opening characteristics, eliminating the need for replacement in assembly units, improving cost performance, and stocking components. It is possible to reduce the amount. Moreover, the measurement points in the manufacturing process and the maintenance process can be reduced, and the burden on the operator can be reduced.
[0010]
In the variable valve mechanism of the present invention, various mechanisms such as a three-dimensional cam and a link mechanism may be realized, or a transmission mechanism using a swing cam may be configured. Since the swing cam has a great influence on the valve opening characteristics of the valve, it is possible to improve the maintainability by installing an adjusting member at a portion in contact with the swing cam and changing the operating angle. By installing the swing cam, the initial phase of the swing cam can be changed and the valve timing can be changed flexibly according to the operating conditions.
[0011]
Further, the position of the contact may be adjusted by installing the adjusting member at a portion where the swing cam and another member are in contact with each other. By so doing, the influence on the valve opening characteristics of the valve is great and suitable for adjustment, so that it is possible to improve adjustment accuracy and maintainability.
[0013]
It is preferable that the adjusting member installed at the contact point is detachably installed in order to facilitate assembly and maintenance. Further, the adjustment member may be a non-axial support member that does not have a rotation shaft. Examples of the non-axial support member include a plate material, a columnar member, a cylindrical member, and a wedge-shaped member. By doing so, it is possible to adjust easily, which is preferable because the maintainability is improved.
[0014]
For example, at least one of the rotating cam contact roller and the swing cam contact roller may be used as an adjustment member. In the swing cam, the adjustment member is fitted into a portion that contacts the swing cam contact roller. It is good also as providing by providing a recessed part and inserting the adjustment member. For example, a flat plate that optimizes valve opening characteristics may be selected from flat plates having different thicknesses. It is good also as providing not only any one but the some member for adjustment.
[0015]
According to the present invention, since the error and variation of the valve opening characteristics can be flexibly optimized with a simple configuration by using the structure of the existing variable valve mechanism, the efficiency of the manufacturing process and the maintainability are improved. Can be improved.
[0016]
In addition to the configuration as the variable valve mechanism described above, the present invention may be configured as a valve opening characteristic adjustment method of the valve in the variable valve mechanism. In this case, the valve control mechanism adjusts the valve operating angle and the lift amount so that the valve operating angle and the lift amount become target values. It is good also as implement | achieving by providing with the process adjusted to this target value. When the lift amount and the working angle are both small, the influence of the error from the target value becomes larger than when both the lift amount and the working angle are set to large values. Therefore, adjustment accuracy can be improved by adjusting the error on the basis of the state where the working angle is small and the lift amount is small, which is preferable.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in the following items.
A. Example:
A1. Variable valve mechanism schematic configuration:
A2. Variable mechanism operation:
A3. Adjustment member:
A4. Valve lift adjustment method:
B. Variation:
[0018]
A. Example:
A1. Variable valve mechanism schematic configuration:
FIG. 1 is a perspective view illustrating a schematic configuration of a variable valve mechanism in the embodiment. A part of the engine is shown. The variable valve mechanism 10 includes a valve 70, a rocker arm 60, a swing cam 30, a connection arm 50, a control shaft 80, a sliding arm 40, a drive cam 20, and a drive camshaft 21. The
[0019]
The rocker arm 60 is configured by a swing arm type, and the valve 70 is opened by pressing the proximal end portion of the valve 70 by the valve pressing portion 61. The swing cam contact roller 62 is formed at the center of the rocker arm 60 so that the pressing surface 31 of the swing arm 32 contacts. A tappet clearance adjustment mechanism 90 is formed at the other end of the valve pressing portion 61 in the rocker arm 60.
[0020]
The swing cam 30 is installed above the rocker arm 60 and includes a pair of swing arms 32 arranged on both sides of the connection arm 50. The pair of oscillating arms 32 are integrated by a not-shown erection part, and a slidable arm 33 that is slid by the slidable contact arm 40 and a valve formed on the slidable part 33 is opened. It is formed from the fitting part 100 which fits the shim 200 which adjusts a valve characteristic. The shim 200 is changed to a shim having a different thickness t, thereby changing the orientation angle of the driven portion 33 and changing the contact position between the swing cam 30 and the rocker arm 60.
[0021]
The connection arm 50 connects the control shaft 80 and the sliding arm 40. The sliding contact arm 40 includes a swing cam contact roller 41, a drive cam contact roller 42, and a connection portion 43. The swing cam contact roller 41 and the drive cam contact roller 42 are each provided with a connection pin 41a. , 42a is rotatably supported. The connection part 43 is connected to the connection arm 50 and a connection pin 43a so as to be rotatable. The drive cam 20 has a nose portion 22 and a base circle portion 23, and is attached to a drive cam shaft 21 that rotates in synchronization with the engine. At the time of operation, the swing cam contact roller 41 is in contact with the driven portion 33, but for convenience of explanation, this figure shows the fitting portion 100 to be visible.
[0022]
With such a configuration, when the drive cam 20 is rotated by the rotational torque of the drive cam shaft 21 and the drive cam contact roller 42 is pressed, the slidable contact arm 40 rotates around the connection portion 43. By this rotation, the rocking cam contact roller 41 pushes the pushed portion 33 and rocks the rocking cam 30, whereby the pressing surface 31 presses the rocker arm 60, and the valve 70 is opened. .
[0023]
FIG. 2 is an exploded perspective view of the variable valve mechanism 10 in the present embodiment. As shown in the drawing, the frame 44 of the sliding contact arm 40 is disposed so as to sandwich the protruding connection portion 51 of the connection arm 50 so that the connection portion 43 and the pinhole 52 coincide with each other. In this state, the sliding arm 40 and the connecting arm 50 are assembled by inserting the connecting pin 43 a through the connecting portion 43 and the pin hole 52. The sliding arm 40 is rotatable around the connection pin 43a.
[0024]
The connection arm 50 is disposed between the pair of swing arms 32 formed on the swing cam 30 so that the shaft insertion portion 54 coincides with the shaft insertion portion 34, and the control shaft 80 is inserted through the fixing tool 55. It is assembled. A detachable shim 200 is fitted and assembled to the driven portion 33.
[0025]
FIG. 3 is a top view of the variable valve mechanism 10 as viewed from above. As shown in the figure, the swing cam 30 and the connection arm 50 are assembled by a control shaft 80, and the sliding contact arm 40 is assembled with the connection arm 50. The drive cam 20 is pivotally attached to the drive cam shaft 21 and presses the drive cam contact roller 42.
[0026]
FIG. 4 is a cross-sectional view illustrating the configuration of the variable valve mechanism 10. FIG. 3 shows a cross-sectional view taken along line AA. As shown in the figure, the connection arm 50 and the control shaft 80 are integrated by a fixing tool 55, and the connection arm 50 rotates as the control shaft 80 rotates.
The sliding contact arm 40 is rotatably connected to the connection arm 50 by a connection pin 43 a, and the swing cam contact roller 41 is a detachable shim 200 installed in the fitting portion 100 of the pushed portion 33. And slide to push the pushed portion 33. When the driven portion 33 is pushed, the orientation angle of the swing cam 30 changes, and the contact position between the swing cam 30 and the rocker arm 60 changes. The rocker arm 60 presses the valve 70 to open it. As the thickness of the shim 200 changes, the amount by which the pushed portion 33 is pressed downward changes. When the variable valve mechanism 10 is assembled or maintained, the contact position is adjusted by adjusting the thickness of the shim 200.
[0027]
A2. Variable operating mechanism:
FIG. 5 is an explanatory view for explaining the operation of the variable mechanism in the present embodiment. This figure shows the operation of the variable mechanism under an operating condition that requires a small lift amount at a small operating angle.
[0028]
FIG. 5A shows a lift base at a small operating angle, that is, a state where the lift amount is 0 mm. The control shaft 80 controls the connection arm 50 so that the rocking cam contact roller 41 and the rocking cam 30 come into contact with each other at the tip of the pushed portion 33. That is, the drive cam 20 is rotated in the direction of arrow B by the rotation of the drive cam shaft 21. The base circle portion 23 of the drive cam 20 abuts at a contact P <b> 1 included in the lower semicircle of the drive cam contact roller 42. At this time, the rocking cam 30 is in contact with the rocker arm 60 and the arc portion 31a of the pressing surface 31 indicated by a one-dot chain line in the drawing, and is not in contact with the tip portion 31b that performs valve pressing. Does not occur.
[0029]
FIG. 5B shows a state at the time of a slight lift with a small operating angle. In the case of transition from FIG. 5A to FIG. 5B, that is, when the contact position between the drive cam contact roller 42 and the drive cam 20 is displaced from the base circle portion 23 to the nose portion 22, the sliding contact arm 40. Rotates around the connection pin 43a as shown by the arrow C, the swing cam contact roller 41 pushes the driven portion 33, the swing cam 30 rotates in the direction of arrow D, and the tip 31b. Swings downward. At this time, the tip 31b of the pressing surface 31 presses the rocker arm 60 with the contact Q2, and pushes down the valve 70. As shown in FIG. 5B, when the contact position between the driving cam contact roller 42 and the nose portion 22 is the contact point P2, the maximum pressure is received, but the swing cam contact roller 41 is driven by the driven portion 33. Therefore, the swing amount of the swing cam 30 is very small, and the lift amount of the valve 70 is also very small.
[0030]
FIG. 6 is an explanatory view for explaining the operation of the variable mechanism in the present embodiment. 6 (a) and 6 (b) show the operation of the variable mechanism under an operating condition that requires the maximum lift amount at a large operating angle. FIG. 6A shows a lift base at a large operating angle, that is, a state where the lift amount is 0 mm. The control shaft 80 has an arrow so that the swing cam contact roller 41 and the swing cam 30 come into contact with each other at the tip of the driven portion 33 and the swing angle becomes maximum when the swing cam 30 swings. Rotate in the direction of E to control the position of the connection arm 50.
[0031]
The drive cam 20 is rotated in the direction of the arrow B by the rotation of the drive cam shaft 21, and the base circle portion 23 comes into contact with a contact P 3 included in the upper semicircle of the drive cam contact roller 42, and the swing cam 30 is rotated around the control shaft 80 in the direction of arrow E. Since the rocker arm 60 is in contact with the circular arc portion 31a of the pressing surface 31 indicated by the alternate long and short dash line in the drawing, and the tip portion 31b that performs valve pressing is not in contact with the rocker arm 60, valve lift does not occur.
[0032]
FIG. 6B shows a state at the time of maximum lift at a large operating angle. In the case of transition from FIG. 6A to FIG. 6B, that is, when the contact position between the drive cam contact roller 42 and the drive cam 20 is displaced from the base circle portion 23 to the nose portion 22, the sliding contact arm 40. Is pressed by the drive cam 20, and the swing cam contact roller 41 pushes the driven portion 33, the swing cam 30 swings as shown by the arrow F, and the tip end portion 31b swings downward. At this time, the distal end portion 31b of the pressing surface 31 presses the rocker arm 60, presses down the valve 70, and valve opening is started. The tip 31b in contact with the rocker arm 60 depresses the rocker arm 60 while changing the contact position to the foremost side as the rocking cam 30 swings. As shown in FIG. 6B, when the contact position between the drive cam contact roller 42 and the nose portion 22 is the contact point P4, the rocker arm 60 receives the maximum pressure, and the swing angle of the swing cam 30 becomes the maximum. The lift amount of the valve 70 is maximized.
[0033]
A3. Adjustment member:
As described above, the position of contact between the components affects the lift amount and working angle of the valve in the variable valve mechanism 10 of the present embodiment. Each component includes an error in the manufacturing stage, and an error in the ideal valve lift and operating angle is increased by assembling. In order to absorb such an error, in this embodiment, the shim 200 is detachably installed on the driven portion 33 that is a contact position between the sliding contact arm 40 and the swing cam 30. Hereinafter, the adjustment by the shim 200 will be described.
[0034]
FIG. 7 is a cross-sectional view for explaining adjustment of the valve by the shim 200 in this embodiment. The shim 200 is fitted and assembled in a fitting portion 100 formed in a concave shape in the driven portion 33. At the time of operation, the sliding contact arm 40 is in contact as shown in the figure, so that it does not come off. In this embodiment, it is not fixed with a fixing tool such as a screw or a fixing agent, but it may be fixed using such a fixing tool.
[0035]
In the present embodiment, the shim 200 is circular, but any shape may be used. The circular shape has an advantage that the shim 200 can be easily formed.
[0036]
By installing the shim 200, the swing cam contact roller 41 comes into contact with the shim 200 at the contact K. By the shim 200, the orientation angle of the pushed portion 33 becomes a downward angle, and the orientation angle of the swing arm 32 also becomes downward. As a result, the position where the rocking cam 30 abuts against the rocker arm 60 is displaced toward the distal end side of the pressing surface of the rocking cam 30, the timing for opening the valve can be adjusted, and the operating angle can be adjusted. Can be adjusted.
[0037]
FIG. 8 is a graph 400 showing the relationship between the thickness t of the shim 200 and the working angle in this embodiment. The standard of the shim thickness t is “0”, which indicates a state in which there is no unevenness from the surface of the driven portion 33. As shown in the figure, the valve operating angle is increased by increasing the thickness t of the shim 200 to “+”, that is, by increasing the thickness. However, due to the configuration of the variable valve mechanism 10, the threshold value “x1” is not exceeded, and the shim thickness t is “y2” at the maximum. Further, by reducing the thickness t of the shim 200 to “−”, that is, by reducing the thickness, the working angle of the valve is reduced. However, since it cannot be made thinner than the thickness “y1” of the driven portion 33, “x2” is the minimum operating angle.
[0038]
As shown in the graph 400, it can be seen that the effect of the shim thickness t on the working angle is greater when the thickness t is “−”, that is, when the shim is thinner than “+”, i.
[0039]
A4. Valve lift adjustment method:
FIG. 9 is a process diagram showing a valve lift adjustment method in this embodiment. The adjustment is started from the state of the assembly in which each component is assembled. In order to perform adjustment, the valve assembly is assembled to a jig (step S10). Next, an error between the target value of the valve lift and the measured value when the valve lift operating angle is small and the lift amount is small is measured (step S11). In the figure, the target value 500 of the valve lift when the operating angle is large and the lift amount is large, and the target value 510 of the valve lift when the operating angle is small and the lift amount is small are indicated by solid lines. The measured value 500a of the valve lift and the measured value 510a of the valve lift when the working angle is small and the lift amount is small are indicated by broken lines. The influence of the error Es between the target value 510 and the measured value 510a on the valve opening characteristics is larger than the error El between the target value 500 and the measured value 500a. Therefore, from the viewpoint of suppressing the influence on the operation of the engine. It is preferable to adjust the error Es.
[0040]
Next, the shim 200 installed in the fitting portion 100 is adjusted by replacing it with a shim having a thickness that absorbs the error Es (step S12), and the valve assembly is removed from the jig and assembled to the engine (step S12). S13).
[0041]
According to the variable valve mechanism 10 of the embodiment described above, by providing an exchangeable adjustment member, when adjusting the valve lift at the time of assembly or maintenance, it is not necessary to replace in units of assembly, and it is simple. The convenience can be improved. By making the adjusting member into a simple shape such as a cylinder or a flat plate, the processing can be facilitated, and the stock amount can be reduced during storage, and the cost can be reduced. Further, in the swing cam that controls the valve lift, there is an advantage that the adjustment accuracy is improved by installing the adjustment member at the connection portion with the sliding arm that exerts a high influence on the swing angle.
[0042]
In addition, according to the variable valve mechanism according to the embodiment, shim adjustment can be easily performed even when the valve assembly is mounted on the engine. Adjustments may be made. In such a case, not only an error in the valve assembly alone but also an error in the valve lift amount due to an assembly error when the valve assembly is assembled to the engine, a manufacturing error of the engine body, or the like can be optimized.
[0043]
Moreover, although the variable valve mechanism 10 of the present invention is formed from a plurality of components, each component includes a manufacturing error that occurs during manufacturing. For this reason, when assembled, a valve lift and an error that become a target value are generated. However, as in the present invention, by providing a shim at a connection part that has a high influence on the swing angle of the swing cam, such a connection part is provided. Since the valve lift can be adjusted by this, there is an advantage that the error of the valve lift can be absorbed even when the accuracy of each component is not so high.
[0044]
For example, when the variable valve mechanism 10 as shown in FIG. 1 is provided in a plurality of cylinders of an internal combustion engine, the variable valve mechanisms 10 of the plurality of cylinders are configured to share a single control shaft 80. Since the valve opening characteristics can be adjusted for each variable valve mechanism 10 of each cylinder, it is possible to easily optimize the valve lift amount between cylinders due to individual differences of the variable valve mechanisms 10. it can. Further, when the variable valve mechanism 10 of one cylinder is replaced during maintenance, there is a possibility that harmony with the variable valve mechanism 10 of another cylinder may be disturbed. By performing 10 shim adjustments, harmony with other cylinders can be easily achieved.
[0045]
B. Variation:
As mentioned above, although embodiment of this invention was described, this invention is not limited to these embodiment at all, In the range which does not deviate from the summary of implementation of this invention, it can implement with various forms. Needless to say. For example, the present invention can be implemented in the form described below.
[0046]
B1. Modification 1:
In the above-described embodiment, the replaceable adjustment shim is provided on the driven portion of the swing cam, which is a contact portion between the swing cam and the sliding arm, but the present invention is not limited to this. The error of the valve lift amount can be adjusted by replacing the swing cam contact roller of the slide contact arm, which is the contact portion between the swing cam and the slide contact arm, with a swing cam contact roller having a different outer diameter. Good.
[0047]
FIG. 10 is a perspective view for explaining a schematic configuration of the variable valve mechanism 1000 in the second embodiment. The variable valve mechanism 1000 has substantially the same configuration as the variable valve mechanism 10 of the embodiment, and the configuration of the pushed portion 33 and the sliding arm 40 is different.
[0048]
The sliding contact arm 40 includes a swing cam contact roller 300, a drive cam contact roller 42, and a connection portion 43, and is connected to the connection arm 50 by a connection pin 43a. The fitted portion 100 is not formed on the driven portion 33 and is not in an uneven state.
[0049]
As shown in the figure, the swing cam contact roller 300 is arranged so that the pin hole 44a formed in the frame body 44 and the pin hole 300a formed in the swing cam contact roller 300 coincide with each other, and the connection pin 41a. Are inserted into the pinhole 44a and the pinhole 300a. The connection pin 41a is fixed from the outside of the frame body 44 by the ring 41b, and the frame body 44 and the swing cam contact roller 300 are integrated.
[0050]
As described above, the orientation angle of the driven portion 33 can be changed by replacing the swing cam contact roller 300 with a roller having a different outer diameter, and the contact between the swing cam 30 and the rocker arm 60 can be changed. The contact position can be changed, and the valve lift can be adjusted. The valve lift adjustment process is the same as that in FIG. 9, and the “shim adjustment” in step S12 may be “swing cam contact roller adjustment”. By doing so, the same effect as in the embodiment can be obtained.
[0051]
B2. Modification 2:
In the above-described embodiment, the shim 200 has a circular flat plate shape and is fitted into the fitting portion 100, but is not limited thereto. For example, it is good also as installing so that the taper-shaped member which becomes thick toward the front-end | tip part from the base end part of the to-be-driven part 33 may be moved. For example, FIG. 11 illustrates the configuration of a variable valve mechanism as a modification of the embodiment. Since the structure other than the structure of the shim 210 is the same as that of the embodiment, the description thereof is omitted.
[0052]
The shim 210 is installed in the fitting portion 101 formed in the pushed portion 33, and the drive cam contact roller 42 slides on the shim 210 and swings the swing cam 30A as in the embodiment. Open the valve. In order to explain the details, an enlarged view 2000 shows a cross-sectional view of a portion indicated by a broken-line circle in the drawing. The shim 210 is fixed during operation, and is movably provided as indicated by an arrow so that the position of the shim can be displaced during valve lift adjustment. When the shim 210 is moved to the position of the shim 210a indicated by the two-dot chain line, the slidable contact arm 40 comes into contact with the contact R ′, and the orientation angle of the driven portion 33 can be changed, and the swing cam Since the contact position between 30 and the rocker arm 60 can be changed, the valve lift can be adjusted. That is, in the embodiment, the same effect as when the thickness of the shim 200 is changed can be obtained.
[0053]
As a method of installing the shim 210, for example, the shim 210 may be supported by a support member 220 as illustrated, or may be fixed by a screw or the like. It is good also as forming the fitting part 101 and the shim 210 with a magnet, and making it adsorb | suck with magnetic force.
[0054]
By adopting such a configuration, it is possible to adjust the valve opening characteristics by displacing the shim 210. Since the adjustment can be performed without replacing the shim, the convenience can be improved. Also, when replacement is necessary during maintenance, such as when the shim 210 is worn, replacement of the assembly unit is not required, and maintenance can be easily performed by replacing the shim 210.
[0055]
B3. Modification 3:
Further, the swing cam contact roller 41 that is a contact point with the drive cam may be exchangeable, or an adjustment member may be inserted between the rocker arm 60 and the swing cam 30. Regardless of the mode, such as providing an adjustment member at the contact portion between the components in the variable valve mechanism, or adjusting the component at the contact portion, the swing angle of the swing cam, the swing start It is preferable to adjust at a part having a high influence on timing.
[Brief description of the drawings]
FIG. 1 is a perspective view illustrating a schematic configuration of a variable valve mechanism in an embodiment.
FIG. 2 is an exploded perspective view of the variable valve mechanism 10 in the embodiment.
FIG. 3 is a top view of the variable valve mechanism 10 as viewed from above.
4 is a cross-sectional view illustrating a configuration of a variable valve mechanism 10. FIG.
FIG. 5 is an explanatory diagram for explaining an operation in an operation situation that requires a large working angle and a maximum lift amount of the variable mechanism in the embodiment.
FIG. 6 is an explanatory diagram illustrating an operation that can be performed in an operation situation that requires a small working angle and a small lift amount of the variable mechanism in the embodiment.
FIG. 7 is a cross-sectional view illustrating adjustment of the valve by the shim 200 in the embodiment.
FIG. 8 is a graph 400 showing the relationship between the thickness t and the working angle of the shim 200 in the example.
FIG. 9 is a process diagram showing a method for adjusting a valve lift in the embodiment.
FIG. 10 is a perspective view illustrating a schematic configuration of a variable valve mechanism 1000 according to a modification.
FIG. 11 is a cross-sectional view illustrating the configuration of a variable valve mechanism in a modified example.
[Explanation of symbols]
10 ... Variable valve mechanism
20 ... Driving cam
21 ... Drive camshaft
22 ... Nose club
23 ... Base Circle Club
30 ... Oscillating cam
31 ... Pressing surface
31a ... Arc portion
31b ... tip
32. Swing arm
33 ... Pushing part
40 ... Sliding arm
41 ... rolling cam contact roller
41a, 42a, 43a ... connecting pins
41b ... Ring
42. Driving cam contact roller
43. Connection part
44 ... Frame
44a, 52 ... pinhole
50 ... Connection arm
51 ... Connection part
54 ... Shaft insertion part
55. Fastening tool
60 ... Rocker arm
61 ... Valve pressing part
62 ... Oscillating cam contact roller
70 ... Valve
80 ... Control shaft
90 ... Tappet clearance adjustment mechanism
100, 101 ... fitting part
200, 210, 210a ... shim
220 ... Support member
300 ... rolling cam contact roller
300a ... pinhole
400 ... Graph
500, 510 ... Target value
500a, 510a ... measured value
1000 ... Variable valve mechanism
2000 ... Enlarged view

Claims (4)

In a variable valve mechanism that transmits the rotational torque of the drive shaft to a valve provided in each cylinder of the engine and controls the valve opening characteristics of the valve,
A transmission mechanism having at least one contact and transmitting a rotational torque of the drive shaft to the valve;
A valve control mechanism for controlling a valve opening characteristic of the valve by controlling the transmission mechanism to change the position of the contact;
Apart from the valve control mechanism, an adjustment member for adjusting the position of the contact in the transmission mechanism is provided at the site of the contact ,
The transmission mechanism is
A rotating cam driven by rotation of the drive shaft;
A swing cam that swings to open the valve;
An intermediate member provided between the rotating cam and the swing cam, and comprising a first contact roller in contact with the rotating cam, and a second contact roller in contact with the swing cam;
A control shaft for adjusting the swing range of the swing cam;
Said intermediate member, said rotary cam, at least one contact in contact with the swing cam, the variable valve mechanism Ru provided with the adjusting member. The variable valve mechanism according to claim 1,
A variable valve mechanism that detachably installs the adjusting member on at least one of the contacts. The adjustment member has no rotary shaft is non-shaft support according to claim 1 or claim 2, wherein the variable valve mechanism. A method for adjusting a valve opening characteristic in a variable valve mechanism that transmits a rotational torque of a drive shaft to a valve provided in each cylinder of an engine and controls a valve opening characteristic of the valve, wherein the variable valve mechanism is the drive A rotating cam driven by rotation of a shaft, a swinging cam swinging to open the valve, a first contact roller interposed between the rotating cam and the swinging cam and in contact with the rotating cam; And a transmission mechanism that includes an intermediate member that includes a second contact roller that contacts the swing cam, and a control shaft that adjusts a swing range of the swing cam, and that transmits rotational torque of the drive shaft to the valve. The intermediate member controls the transmission mechanism so as to change the position of at least one of the contact points in contact with the rotating cam and the swing cam. A valve control mechanism for controlling, separately from the valve control mechanism, the adjusting member for adjusting the position of the contacts in the transmission mechanism comprises a portion of said at least one contact, and,
Adjusting the valve control mechanism so that the valve operating angle and the lift amount become target values;
Adjusting the valve operating angle and the lift amount to a predetermined target value by adjusting the adjusting member in the adjusted state.

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