JP5196176B2 - Variable valve assembly adjustment method - Google Patents

Description

  The present invention relates to an assembly adjustment method for adjusting variation between cylinders of a variable valve assembly that is variably assembled from a low valve lift to a high valve lift.

Recently, in a reciprocating engine (internal combustion engine) installed in an automobile, the valve drive output of an intake valve is continuously controlled by a cylinder head in order to prevent engine exhaust gas and improve pumping loss. A variable valve system is being installed.
In many variable valve systems, at least the valve lift amount of the intake valve is continuously changed in order to adjust the intake air amount. For example, as disclosed in Patent Document 1, the cam displacement of the intake cam formed on the camshaft is received by a variable valve mechanism, and the valve drive output from the intake cam is generated by the displacement of the control shaft (control member). A mechanism is used in which the intake valve is driven by continuously changing the valve lift from a low valve lift to a high valve lift and transmitting it to the valve drive member.

By the way, normally, the valve system of an engine has assembled each member of a valve system for every cylinder using the head assembly line which assembles a cylinder head. Therefore, the assembly of the variable valve system is also assembled to the cylinder head that flows through the head assembly line.
However, since the variable valve system has a large number of assembly man-hours, it places a considerable burden on the head assembly line.

Therefore, using the technique for assembling the rocker arm assembly disclosed in Patent Document 2, the parts of the variable valve system excluding the valve and the camshaft are assembled at a place different from the head assembly line, and this variable valve It is conceivable to assemble the system assembly to the cylinder head after the camshaft has been assembled.
However, in the case of a variable valve system, unlike the rocker arm assembly as in Patent Document 2, since the valve lift characteristics between cylinders are not uniform, it is necessary to adjust the variation among cylinders to suppress the variation in combustion among the cylinders. This adjustment can be performed only when the camshaft is assembled.

  Therefore, it is conceivable to adjust the variation among the cylinders using a variable valve assembly assembled together with a control shaft, a valve driving member, and the like. However, the variation adjustment between cylinders usually measures the valve lift height at each lift position from the low valve lift position to the high valve lift position, and confirms whether there is variation between cylinders from the measured valve lift height position. Is used. When there is a variation that deviates from the specified tolerance, the valve lift amount is adjusted so as to be within the tolerance.

JP 2005-299536 A JP-A-10-249656

However, such variation adjustment between cylinders is considerably troublesome because it is required to measure at each lift position or to determine variation in the measured valve lift heights.
SUMMARY OF THE INVENTION An object of the present invention is to provide a variable valve assembly adjusting method capable of easily adjusting the variation between cylinders of a variable valve assembly assembled with a camshaft with high adjustment accuracy.

According to the first aspect of the present invention, in order to achieve the above object, the adjustment of the variation between cylinders of the variable valve assembly is performed by displacing the control member in the high valve lift direction and setting it to an arbitrary lift position. After adjusting the difference in valve lift height output from each valve drive member within a predetermined tolerance, the control member is displaced in the low valve lift direction opposite to the high valve lift direction, so that the predetermined low valve Positioning at the lift position that is the lift amount, check whether the difference in valve lift height output from each valve drive member at that lift position is within the specified tolerance at the lift position , and exceeds the specified tolerance In this case, the adjustment is performed again at an arbitrary position on the high valve lift side or by performing a fine adjustment on the low lift side .

  In other words, in the variable valve system, the difference in the amount of air drawn into the engine appears as a large difference in engine characteristics (for example, the engine speed changes when the valve lift differs during idle rotation), so the valve lift is lower than the high valve lift position. There is a characteristic that the position requires higher accuracy. Therefore, considering this characteristic, after adjusting the valve lift height at a point on the high valve lift side where the required accuracy is low, instead of the position of a certain low valve lift amount where accuracy is required, If it is confirmed that the valve lift height is within the specified tolerance at the predetermined lift position, the variation of the valve lift height at a point where accuracy is not required, such as high valve lift, requires adjustment accuracy. Even if it is replaced with a fixed low valve lift amount, it can be kept within a small tolerance, so there is no need for the troublesome task of determining whether it is within the tolerance at multiple points, and there is variation between cylinders. Adjusted. That is, the variation among cylinders of the variable valve assembly can be adjusted easily and with high adjustment accuracy. In particular, work on the high valve lift side is simple because precision is not required.

According to the second aspect of the present invention, since the displacement detection sensor for detecting the displacement of the control member is also adjusted, the displacement detection sensor is output from each valve driving member at a lift position where the valve lift amount is low. When it is confirmed whether the difference in the valve lift height is within the specified tolerance, the adjustment is made so that the desired sensor output is obtained.
According to the third aspect of the present invention, since the stopper portion that defines the variable range of the valve lift of the control member is also adjusted, the position of the stopper portion is a lift position where the valve lift amount is low, and each valve drive When it was confirmed that the difference in the valve lift height output from the member was within the specified tolerance, the control member was adjusted so as to restrict the movement of the control member at the end of the variable range of the valve lift.
According to a fourth aspect of the present invention, the control member includes a control shaft disposed in parallel with the camshaft, and the variable valve mechanism is configured to reduce the cam displacement of the cam by rotating the control shaft. It is variable between the high valve lift and the inter-cylinder variation adjustment is performed by advancing and retracting the inter-cylinder variation adjusting screw screwed into a through hole formed in a direction perpendicular to the axis of the control shaft. To do.

According to the first and fourth aspects of the invention, by utilizing the characteristics of the variable valve system in which a higher accuracy is required at the low valve lift position than at the high valve lift position, As long as the variation in the valve lift height at a point is within a small tolerance even if it is replaced by a point with a certain amount of low valve lift that requires accuracy, it is determined whether or not it is within tolerance at multiple points. It is possible to adjust the variation among the cylinders in the variable valve system assembly without requiring the troublesome work of doing.

Therefore, even if it is not a skilled worker, the dispersion | variation adjustment between the cylinders of the variable valve assembly which assembled the camshaft can be performed by easy work and also with high adjustment accuracy. In particular, work on the high valve lift side does not require precision, so the workload is light.
According to the second aspect of the present invention, the displacement detection sensor for detecting the displacement of the control member can be easily adjusted with high adjustment accuracy.

  According to the invention of claim 3, the adjustment of the stopper portion that defines the variable range of the valve lift of the control member can be easily performed with high adjustment accuracy.

The perspective view which shows the variable valve assembly used as the object of the variable valve assembly adjustment method which concerns on one Embodiment of this invention with the adjustment jig | tool which performs the dispersion | variation adjustment between cylinders. The perspective view which shows the state which assembled | attached the variable valve assembly to the adjustment jig. Sectional drawing in alignment with the AA in FIG. 2 for demonstrating the operation | work which sets the control shaft to the arbitrary positions on the high valve lift side, and the operation | work which adjusts the difference of valve lift height in the same position. Sectional drawing explaining the check operation | work of the valve lift height in the position used as fixed low valve lift amount. The figure for demonstrating how to adjust the displacement detection sensor assembled | attached to a control shaft. Sectional drawing of the reduction gear part in alignment with the B line in FIG. Sectional drawing of the stopper part which follows the CC line in FIG. The diagram which shows the valve lift height at the time of valve lift large. The diagram which shows the valve lift height when it replaces at the time of valve lift small.

Hereinafter, the present invention will be described based on an embodiment shown in FIGS.
FIG. 1 shows a variable valve assembly 1 used in a multi-cylinder engine that is subject to adjustment of variation among cylinders, together with an adjustment jig 40 used for adjustment of variation among cylinders of the assembly 1, and FIG. The state when the valve assembly 1 is assembled to the adjustment jig 40 is shown, and FIG. 3 shows a cross-sectional view (A-A line in FIG. 2) at that time.

Here, before explaining the method for assembling and adjusting the variable valve assembly 1, the variable valve assembly 1 to be adjusted will be described.
As shown in FIGS. 1 to 3, the variable valve assembly 1 includes a plurality of holder members 2 arranged along a cylinder row at an inter-cylinder pitch, and a support shaft 10 that extends over the upper part. An exhaust rocker shaft 12 is assembled on one side to form a frame, and a control shaft 13 that also serves as an intake rocker shaft is rotatably assembled across the holder member 2 on the intake side (opposite side of the exhaust rocker shaft 12) of the frame. Further, the camshaft 17 is rotatably assembled to the lower part of the holder member 2 with a cam cap 15. For each cylinder, a double-head intake rocker arm 22 (corresponding to the valve drive member of the present application) that drives an intake valve (not shown) is rotatably mounted on the control shaft 13. Further, as shown in FIG. 3, the valve characteristics of the intake cam 17a can be varied between the intake rocker arm 22 and the intake cam 17a of the camshaft 17 for each cylinder. Here, the valve lift amount, the opening / closing timing, and the opening / closing period are controlled. A variable valve mechanism 19 that is variable according to the rotational displacement of the shaft 13 is assembled. The variable valve mechanism 19 has an inter-cylinder variation adjusting screw 35 that adjusts the variation between cylinders. That is, the camshaft 17, the intake rocker arm 22, and the variable valve mechanism 19 with a variation adjusting function are integrated. The exhaust rocker shaft 12 is assembled with an exhaust rocker arm 20 (not shown) for uniquely opening and closing an exhaust valve (not shown), and an input for inputting a valve lift is provided at one end of the control shaft 13. Part, for example, a worm-type speed reducer part 4 (consisting of a worm wheel 4a and a worm shaft 4b) is assembled. Reference numeral 4c denotes a fixing bolt for fixing the worm wheel 4a to the end of the control shaft 13. Further, for example, the worm wheel 4 a is assembled with a stopper portion 7 that defines the minimum valve lift position of the control shaft 13. Further, a control shaft displacement detection sensor 6 (illustrated in FIG. 2: corresponding to the displacement detection sensor of the present application) for detecting the rotational displacement of the control shaft 13 is assembled to the other end portion of the control shaft 13.

  Further, the variable valve assembly 1 will be described. The variable valve mechanism 19 includes a swing cam 25 having one end swingably supported by the support shaft 10 as shown in FIG. A structure in which an L-shaped center rocker arm 27 interposed between a lower portion of 25 and an intake cam 17a is combined is used. The control shaft 13 and the center rocker arm 27 correspond to the control member of the present application.

That is, as shown in FIG. 3, the rocking cam 25 has a cam surface 25a extending in the rocking direction at the other end and a roller 25b at the bottom. Of these, the cam surface 25 a is in rolling contact with the roller 22 a assembled to the proximal end portion of the intake rocker arm 22.
As shown in FIG. 3, the center rocker arm 27 has a slope 28 on the tip surface of the arm portion 27 a going upward, and a bendable pin member 29 on the tip portion of the arm portion 27 b going to the control shaft 13, A rotatable roller 30 is provided at a portion where the arm portions 27a and 27b intersect. Of these, the slope 28 is in rolling contact with the roller 25b of the swing cam 25, and the roller 30 is in rolling contact with the cam surface of the intake cam 17a. The pin member 29 is inserted into a through hole formed in the control shaft 28 so as to freely advance and retract. By this insertion, the center rocker arm 27 is swingably supported with the bent portion of the pin member 29 as a fulcrum, and when the control shaft 13 is rotationally displaced, the center rocker arm 27 as a whole changes the rolling contact position with the intake cam 17a. However, the cam surface of the intake cam 17a is displaced in the advance direction or the retard direction. This displacement changes the posture of the swing cam 25 to change the region of the cam surface 25a on which the roller 22a rolls, and the valve drive output (cam displacement) output from the intake cam 17a, for example, the valve of the intake valve 17a. The lift amount, opening / closing timing, and opening / closing period are continuously varied (from the low valve lift phase to the high valve lift phase). This variable valve drive output is transmitted to the intake rocker arm 22 and is applied to an intake valve (not shown) from an adjustment screw portion 22b (a portion in contact with the valve) at each tip of the intake rocker arm 22. In addition, the cylinder-to-cylinder variation adjusting screw 35 (adjusting portion) described above is screwed into the through hole into which the pin member 29 is inserted from the upper side opposite thereto so that the cylinder member can be advanced and retracted. The amount of protrusion 29 changes and the valve lift can be adjusted (for each cylinder).

  Such a variable valve assembly 1 (including the camshaft 17) is assembled and assembled at a location different from the line for assembling the cylinder head. However, since it is only assembled, the valve lift characteristics between the cylinders are not uniform. , It is scattered. If it varies, the engine combustion varies between cylinders. Therefore, the assembled variable valve assembly 1 is required to adjust the variation between the cylinders before assembling to the cylinder head so as to correct the variation among the cylinders (assembly adjustment).

The adjusting jig 40 is used for adjusting the variation between cylinders. As the adjusting jig 40, for example, a box-shaped jig with a lift sensor having an outer shape corresponding to the cylinder head of the engine as shown in FIGS. 1 to 3 is used.
Here, the box-shaped jig will be described. The jig has an elongated main body 40a corresponding to the cylinder head corresponding to the number of cylinders of the engine as shown in FIG. 1, and the upper center of the main body 40a. The assembly arrangement | positioning part 41 for arrange | positioning the variable valve assembly 1 is formed. On both sides of the assembly arrangement portion 41, a plurality of seats 42 for mounting the leg portions 2a on both sides of the holder member 2 of the variable valve assembly 1 are formed. These receiving seats 42 are formed with knock pins 43 that can be inserted into the bolt holes 2b formed at the ends of the leg portions 2a. The receiving seat 42 and the knock pin 43 are portions for positioning the holder members 2 and the intake rocker arm 22 at fixed positions, thereby adjusting the variable valve assembly 1 in the same posture as when it is mounted on the cylinder head. It can be assembled to the upper part of the jig 40. A lift sensor 45 for detecting the valve lift amount of the intake valve is embedded at each position where the intake valve is arranged in the assembly arrangement portion 41. As shown in FIG. 3, each of these lift sensors 45 has a structure in which a bottomed cylindrical advance / retreat member 46 that is displaced like an intake valve is incorporated so as to be able to advance and retract. That is, the advancing / retreating member 46 is assembled with a spring member 47 that urges in a direction protruding upward, and is set to generate a preload with zero valve lift. Further, the advance / retreat member 46 is assembled with a detection element 48 for detecting the displacement amount of the advance / retreat member 46 so that the valve lift amount output from the end of the intake rocker arm 20 is detected from the displacement of the advance / retreat member 46. ing. The lift sensor 45 may have another structure.

In addition, at the point where the exhaust valve of the assembly disposing portion 41 is disposed (exhaust side), an extendable holder 49 for receiving the end of the exhaust rocker arm 20 is embedded.
Next, a method of adjusting the variation between cylinders of the variable valve assembly 1 using the adjusting jig 40 will be described.
Since the variable valve assembly 1 assembled in the previous process (here, the control shaft displacement detection sensor 6 is not assembled) is only assembled, the valve lift characteristics between the cylinders are not uniform.

  Therefore, first, when adjusting the variation between cylinders, the specifications are set to be constant for each cylinder. For this purpose, the protruding amount of the inter-cylinder variation adjusting screw 35 of each variable valve mechanism 19 and the protruding amount of the adjusting screw portion 22b of each intake rocker arm 22 are uniformly matched. And these dispersion | variation adjustment screws 35 and adjustment screw part 22b are temporarily fixed.

  When the operation is completed, the variable valve assembly 1 is assembled to the adjustment jig 40. For example, as shown in FIG. 1 to FIG. 3, first, the end of the leg portion 2 a having the bolt hole 2 b is placed on the seat 42 while fitting the bolt hole 2 b of each holder member 2 to the knock pin 43. As a result, the adjustment screw portion 22b of each intake rocker arm 22 is positioned at the tip end portion (the end of the advancing / retreating member 46) protruding from the lift sensor 45 for each cylinder as shown in FIG. Thus, each lift sensor 45 comes into contact with the tip of each adjustment screw 22b, and a system for receiving the output from the intake rocker arm 22 is prepared. Subsequently, the variable valve assembly 1 is fixed. For this, for example, a bolt member 37 (shown in FIG. 1) used for fixing the support shaft 10 or a bolt member 38 (only a part of which is shown in FIG. 3) used for fixing the exhaust rocker shaft 12 is used. . Specifically, as shown in FIG. 1, bolt members 37 and 38 are inserted from the rocker shaft fixing hole 2c (only the bolt member 37 is shown) formed in the holder member 2, and the assembly is arranged. This is performed by screwing into a screw hole 41a (shown in FIG. 1) formed in the portion 41 and tightening with a specified torque.

  When the assembly of the variable valve assembly 1 is completed, the valve lift height is adjusted at an arbitrary lift position on the high valve lift side. For this, first, the worm shaft 4b of the speed reducer section 4 is operated to rotationally displace the control shaft 13, and for example, as shown in FIG. 3, the attitude of the control shaft 13 is changed to an arbitrary angle on the high valve lift side. Set to an arbitrary lift position on the high valve lift side. The camshaft 17 is rotated at the lift position at an arbitrary angle, and the valve lift height output from the intake rocker arm 22 is measured by the lift sensor 40. That is, when the camshaft 17 rotates, the cam displacement of the intake cam 17a is transmitted to the swing cam 25 via the center rocker arm 27 and swings the intake rocker arm 22. The lift sensor 40 follows the oscillating displacement of the intake rocker arm 22 and moves in the vertical direction (reciprocating direction), and measures the valve lift height shown in FIG. 8 output from each intake rocker arm 22 based on the cam rotation angle. And record. Here, the maximum valve lift height that is easy to grasp is measured (broken line). When the measurement is finished, the inter-cylinder variation adjusting screw 35 of each cylinder is operated so that the average of the maximum valve lift height between the cylinders is within a predetermined tolerance. This completes the adjustment of the valve lift height on the high valve lift side (solid line).

  When the adjustment of the valve lift height is completed, the control shaft 13 is then rotated and displaced in the opposite low valve lift direction as shown by the arrow α in FIG. 3, and the control shaft 13 is moved as shown in FIG. , Positioned and held at an angle that provides a predetermined low valve lift. Specifically, the control shaft 13 is positioned at an angle at which the average of the maximum valve lift height is a constant low valve lift amount.

Thereafter, the camshaft 17 is rotated, and the maximum valve lift height output from each intake rocker arm 22 is measured from the lift sensor 40 at the same lift position (low valve lift amount). It is confirmed whether or not the difference between the measured maximum valve lift heights falls within the predetermined tolerance of the low valve lift position.
At this time, as shown by the solid line in FIG. 9, the variable valve assembly 1 is determined that the variation among the cylinders has been adjusted if it falls within the specified tolerance.

  That is, the variable valve system assembly 1 requires a higher accuracy at the low valve lift position than at the high valve lift position because the difference in the amount of air drawn into the engine appears as a difference in engine characteristics. In the variable valve mechanism 19 using the swing cam 25, the swing cam 25 is used as a valve lift when the swing cam 25 slightly enters the lift section from the base circle section at the low valve lift position. Is small. That is, even if the position of the swing cam 25 is adjusted by the adjusting screw 35 and a lift change is applied, the lift displacement amount is small, and the adjustment sensitivity is low. However, at the high valve lift position, the swing cam is used as a valve lift when it enters the lift section largely from the base circle section. Therefore, the lift section has a large lift displacement, and the position of the swing cam 25 is adjusted by the adjusting screw 35. When a lift change is applied after adjustment, the amount of lift displacement increases and adjustment sensitivity is high. Therefore, in consideration of this characteristic, after adjusting the valve lift height at a point on the high valve lift side where the adjustment sensitivity is high, the lift position in FIG. As shown by the solid line, if it is confirmed that each valve lift height at the lift position is within the specified tolerance at the predetermined lift position, the valve lift height at a point where high valve lift accuracy is not required. Even if it is replaced with a fixed low valve lift point where adjustment accuracy is required, the variation in the range is within a minute tolerance. Thereby, it is possible to adjust the variation between cylinders without requiring a troublesome operation of determining whether or not a plurality of lift positions are within tolerance. If the adjustment is finalized, the cylinder-to-cylinder variation adjusting screw 35 that has been adjusted is fixed by a fixing nut 35 a that is screwed into the adjusting screw 35. If the specified tolerance is exceeded as shown by the broken line in FIG. 9, the process returns to the operation for setting at an arbitrary position on the high valve lift side again, and adjustment of the variation between cylinders is performed again. Alternatively, fine adjustment may be made on the low lift side.

  Therefore, the variable valve assembly 1 can easily adjust the variation between the cylinders only by the process of adjusting the high valve lift at an arbitrary position and then checking the tolerance at the constant low valve lift position. In addition, since high accuracy is required at the low valve lift position rather than the high valve lift position, high adjustment accuracy can be expected while performing easy work. In particular, since the work on the high valve lift side does not require precision, it is simple, and even if it is not a skilled worker, the variation between cylinders can be adjusted.

In addition, after the adjustment of the variation between the cylinders is completed, the control shaft displacement detection sensor is arranged so that the sensor output becomes an angle at which the sensor output becomes a set value at the end of the control shaft 13 as shown in FIGS. If the body 6b of the sensor 6 is fixed to the holder member 2 with screws after the input portion 6a of 6 is set, the control shaft displacement sensor 6 can be easily adjusted.
In addition, when the position of the stopper portion 7 is adjusted as shown in FIGS. 6 and 7 after the adjustment of the variation between the cylinders, the control of the variable range end of the control shaft 13 can be easily performed. That is, here, the stopper portion 7 extends from the point near the minimum valve lift position (variable range end) to an arc shape formed on the worm wheel 4a, as shown in FIGS. 6 and 7, for example. A structure is used in which the screw member is screwed so as to be able to advance and retract through the long hole 7a, and a short cylindrical worm stopper 7c is loosely inserted around the bolt member 7b. When the bolt member 7b is screwed into the holder member 2, the worm When the stopper 7c is fixed while being inserted into the long hole 7, and the bolt member 7b is loosened, the worm stopper 7c can be freely displaced. Initially, the bolt member 7b is loosened. For this reason, in the stopper portion 7, after adjusting the variation, as shown in FIG. 7, the worm stopper 7 c is pressed against the end of the long hole 7 a in the low valve lift direction, and the bolt member 7 b remains in the same state. Is screwed into the holder member 2 and the worm stopper 7c is fastened between the head of the bolt member 7b and the holder member 2, the variable range end of the control shaft 13, here, the minimum valve lift position is positioned. Movement is regulated. That is, the stopper portion 7 can be easily adjusted.

  If necessary, after that, the control shaft 13 is rotated in the high valve lift direction, and the maximum valve lift height corresponding to the lift position is measured by the lift sensor 45 at the highest valve lift position. If the control shaft displacement sensor 6 is rotated within the range of low valve lift to high valve lift and the control shaft displacement sensor 6 confirms that the specified sensor output is output, Certainly. Then, if the set various data is marked on the holder member 2 or the like with a marking portion such as a QR code, valve clearance adjustment performed by mounting on the cylinder head after that becomes easy.

In addition, by measuring the lift of the cam rotation angle, it is possible not only to set the measurement standard as the maximum lift amount but also to make adjustments by comparing the valve lift at the specified cam rotation angle and the integrated value of the valve lift as a whole. Then, the cylinder variation adjustment accuracy can be further increased.
Further, when the variable mechanism 19 is provided for each valve, if there is a difference in the valve lift in the same cylinder, the same adjustment as the inter-cylinder variation adjustment is performed.

In addition, if the adjustable width is greatly exceeded, it is possible to easily determine the defect of the component part, and it is also possible to identify the defective part according to the deviation of the measured value during adjustment, and manage the measured value By doing so, product defects can be easily identified, and productivity is increased. Furthermore, productivity is further improved by feeding back the information to correction at the time of manufacturing the child parts.
Note that the present invention is not limited to one embodiment, and various modifications may be made without departing from the spirit of the present invention. For example, in one embodiment, the adjustment jig is used to adjust the variation among cylinders of the variable valve assembly, but this is not limiting, and the variable valve assembly is directly mounted on the cylinder head. In this state, the variation between cylinders may be adjusted. In one embodiment, a variable valve mechanism that varies the valve lift using a swing cam is used. However, a variable valve mechanism that varies the valve lift using another structure may be used.

1 Variable valve assembly 6 Control shaft displacement detection sensor (displacement detection sensor)
7 Stopper 13 Control shaft (control member)
17 Camshaft 19 Variable valve mechanism 22 Intake rocker arm (valve drive member)
27 Center rocker arm (control member)

Claims (4)

A camshaft including a cam; a valve driving member for each cylinder that drives the valve; and a control member that inputs a valve lift. The cam displacement of the cam depends on the displacement of the control member. A variable valve assembly comprising a variable valve mechanism that is variable between a valve lift and transmitted to the valve drive member, and a variable valve assembly adjustment method that adjusts variation among cylinders in the assembly,
To adjust the variation among cylinders of the variable valve assembly, the control member is displaced in the high valve lift direction and set at an arbitrary lift position, and the difference in valve lift height output from each valve drive member at the lift position is set. After adjusting within a predetermined tolerance, the control member is displaced in a low valve lift direction opposite to the high valve lift direction and positioned at a lift position where a predetermined low valve lift amount is obtained. Check if the difference in the valve lift height output from the drive member is within the specified tolerance at the lift position.If the difference exceeds the specified tolerance, adjust again at an arbitrary position on the high valve lift side. A variable valve assembly adjustment method, characterized in that it is performed by performing fine adjustment on the low lift side . The variable valve assembly includes a displacement detection sensor for detecting a displacement of the control member,
When it is confirmed that the difference in valve lift height output from each valve drive member is within the specified tolerance at the lift position where the low valve lift amount is obtained, the displacement detection is performed so that the desired sensor output is obtained. The variable valve assembly adjusting method according to claim 1, wherein the sensor is adjusted. The variable valve assembly includes a stopper portion that defines a variable range of a valve lift of the control member,
When it is confirmed that the difference in valve lift height output from each valve drive member is within a specified tolerance at the lift position at which the low valve lift amount is achieved, the control member moves at the end of the variable range. The variable valve assembly adjustment method according to claim 1, wherein the position of the stopper portion is adjusted so as to be regulated. The control member includes a control shaft disposed in parallel with the camshaft,
The variable valve mechanism is configured to vary the cam displacement of the cam between a low valve lift and a high valve lift by rotationally displacing the control shaft,
The cylinder-to-cylinder variation adjustment is performed by advancing and retracting a cylinder-to-cylinder variation adjusting screw screwed into a through hole formed in a direction perpendicular to the axis of the control shaft.
The variable valve assembly adjusting method according to claim 1, wherein:

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