JPH11210427A - Three dimensional cam, three dimensional cam profile acceptance or rejection judgment method, three dimensional cam profile measurement element, three dimensional cam profile measurement method, and three dimensional cam profile measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent only an edge part from being in contact with a cam surface so as to prevent stripe traces from being formed on the cam surface by protrudedly forming the height distribution of an area in contact with the sliding surface of a cam follower of a three dimensional cam, even if there exist a manufacturing error, in place of forming it linearly. SOLUTION: The cam surface 11a of an intake side cam is designed so that its tangential line 46 is formed protrudedly. By this, the edge part of a cam follower is not brought in contact strongly with the cam surface 11a, and the cam surface 11a is not damaged by the edge part. As a result, the edge part of the cam follower is not caught by the strap traces when the intake side cam is moved in its axial direction, and the switchover of the opening and closing timing and lift amount of the intake valve can be maintained smoothly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional cam having a cam surface with which an oscillating cam follower abuts and whose cam profile continuously changes in the direction of the rotation axis. The present invention relates to a three-dimensional cam which is used as a cam for driving an intake valve and an exhaust valve of an internal combustion engine, and changes the cam profile according to the operating conditions of the internal combustion engine to control the opening and closing characteristics of those valves. Further, the present invention relates to a three-dimensional cam cam profile pass / fail determination method for the three-dimensional cam, a three-dimensional cam profile gauge, a three-dimensional cam profile measuring method, and a three-dimensional cam profile measuring device.

[0002]

2. Description of the Related Art Hitherto, as a mechanism for continuously changing a valve opening angle and a lift amount of an intake valve and an exhaust valve of an internal combustion engine, a configuration as shown in FIG. -45803, JP-A-9-32519
No.). That is, as a cam corresponding to the two valves 543 on the intake side or the exhaust side, a three-dimensional cam 540 whose cam nose height continuously and continuously changes in the rotation axis Y direction of the cam shaft 542 is used. The three-dimensional cam 540 together with the camshaft 542
Is displaced in the direction of the rotation axis Y, whereby the valve 543 is displaced.
There has been proposed a valve characteristic control device in which the cam nose height of the cam surface 540a for driving each of the above-mentioned is continuously and continuously changed.

In such a valve characteristic control device, the valve 543 is determined by the difference between the maximum and minimum cam nose heights.
(Hereinafter referred to as a lift control amount) is determined. Then, for example, the camshaft 5 is set so that the maximum lift amount of the valve 543 is small in the low engine speed region and large in the high engine speed region.
By controlling the movement of the 42 in the direction of the rotation axis Y, it is possible to always obtain favorable engine characteristics in terms of torque and stability, whether in a low speed range or a high speed range.

Here, in the configuration shown in FIG. 20, a valve lifter 549 is provided between the valve 543 and the three-dimensional cam 540, and a cam follower holder 544 is integrally formed at the center of the upper surface. Have been. Then, the cam follower 545 mounted on the cam follower holder 544 is connected to the cam surface 54 of the three-dimensional cam 540.
It swings along 0a.

The surface of the cam follower 545 is a cam surface 540.
a sliding surface 545a that slides in contact with a. The shape of the cam follower 545 is shown in FIG. FIG. 21A shows a vertical cross section of the cam follower 545, and the cross section has a semicircular shape. FIG. 21 (b)
Indicates a side surface of the cam follower 545.

[0006]

In the configuration in which the three-dimensional cam 540 does not move in the direction of the rotation axis Y, there are the following problems.

As shown in FIG. 22, the cam follower 545 is linear with respect to the cam surface 540a of the three-dimensional cam 540 from an edge portion 545b arranged on the low lift side to an edge portion 545c arranged on the high lift side. Contact. Hereinafter, this linear contact portion is referred to as a tangent line.
FIG. 23 shows this tangent line 546 by a solid line.

FIG. 23 shows a cam surface 54 of a three-dimensional cam 540.
FIG. 11 is a perspective view showing a cam profile of Oa, which continuously changes from a low-lift cam profile 547 shown by a broken line to a high-lift cam profile 548 shown by a dashed line as shown in the figure. The above-mentioned tangent line 546 shown by a solid line is linear, and connects the low lift side cam profile 547 and the high lift side cam profile 548. The tangent line 5 shown in FIG.
The reference numeral 46 denotes the shape and direction of the cam surface 54, while the rotation phase is spaced apart to show the shape and direction.
0a is present on the entire surface.

Also, as shown in FIG.
Since 5a is in contact with a portion from the low lift side cam profile 547 to the high lift side cam profile 548, the tangent line between the sliding surface 545a and the cam surface 540a is represented by a solid line in FIG. This corresponds to a part of the length of each tangent.

Therefore, when the three-dimensional cam 540 moves in the direction of its rotation axis Y, as shown in FIG. 22, the cam follower 545 is in contact with the tangent line 546 from one edge 545b to the other edge 545c. Thus, the sliding surface 545a slides on the cam surface 540a.

Here, as shown in FIG. 23, the cam surface 540a is formed precisely so that the above-mentioned tangent line 546 is linear, but due to an error in the manufacturing process, the tangent line 546a is formed.
Is considered to be concave in the height direction. Then, as shown in FIG. 24, the edge portions 545b and 545c
Only the cam surface 540a is in contact with the cam surface 540a, and the edge portions 545b and 545c may bite into the rotating cam surface 540a to form a streak, and the cam follower 545 itself may wear only the edge portions 545b and 545c.

Further, when the streaks are formed on the cam surface 540a as described above, when the three-dimensional cam 540 moves in the rotation axis Y direction, the edge portion 545 of the cam follower 545
There is also a possibility that b and 545c may be caught by the streaks, making it impossible to smoothly switch the opening / closing timing of the intake valve and the exhaust valve and the lift amount.

SUMMARY OF THE INVENTION The present invention has been made for the purpose of preventing damage to a three-dimensional cam due to an edge of a cam follower, and a three-dimensional cam capable of preventing the above-described damage, and a pass / fail of the three-dimensional cam capable of preventing the damage. Three-dimensional cam profile pass / fail judgment method for judging, a three-dimensional cam profile gauge that can measure a cam profile of a three-dimensional cam that can prevent damage, a three-dimensional cam profile measuring method using the three-dimensional cam profile gauge, And a three-dimensional cam profile measuring device.

[0014]

According to a first aspect of the present invention, there is provided a three-dimensional cam having a cam surface with which a swinging cam follower abuts, and a cam profile continuously changing in the direction of the rotation axis. A three-dimensional cam, wherein a height distribution in a rotation axis direction of a contact position between the cam follower and the cam surface in the same rotation phase of the three-dimensional cam is convex.

That is, the portion where the sliding surface of the cam follower comes into contact is not a linear shape as in the related art, but has a convex height distribution. For this reason, even if there is a manufacturing error of the three-dimensional cam, the cam surface of the three-dimensional cam does not become concave as in the related art, so that only the edge portion can be prevented from contacting the cam surface, and the cam surface can be prevented. No streak is formed. Further, the same applies to the case where the height distribution is accurately measured to be convex as described later and judgment and selection are performed.

Therefore, when the three-dimensional cam moves in the direction of its rotation axis, the edge of the cam follower does not catch on the streak, and the opening / closing timing of the intake valve and the exhaust valve and the smooth switching of the lift amount are maintained. be able to.

Here, as described in claim 2, by being attached to the camshaft, the intake valve or the exhaust valve of the internal combustion engine is opened / closed, and the camshaft is moved based on the movement in the rotation axis direction. By configuring the cam as a three-dimensional cam characterized by changing the opening / closing characteristics of the intake valve or the exhaust valve, the present invention is applied to an internal combustion engine, so that the continuous opening / closing timing and lift of the intake valve or the exhaust valve can be smoothly performed. Can switch.

According to a third aspect of the present invention, there is provided a three-dimensional cam profile pass / fail determination method according to the first or second aspect, wherein the cam surface is aligned with the rotation axis of the three-dimensional cam. A measurement step of obtaining a height or a physical quantity corresponding to the height as a measurement value, and of the measurement values obtained in the measurement step, at the same rotational phase of the three-dimensional cam and at different positions in the rotational axis direction. A step of determining a pass when a change in a plurality of measured values indicates a convex pattern and the convex pattern is within an allowable range.

In such a measuring step, for example, a contact similar to a cam follower is brought into contact with the cam surface,
The height of the cam surface, that is, the distance from the rotation axis of the three-dimensional cam can be obtained by the position fluctuation of the probe similar to the cam follower. In the measurement step, the physical state corresponding to the height of the cam surface may be obtained as a measured value because the state of the height of the cam surface may be determined without directly obtaining the height of the cam surface. For example, by setting a reference point outside the three-dimensional cam,
It may be measured as angle and distance data from there,
Alternatively, instead of the data of the angle and the distance, it may be obtained as a voltage or other physical quantity output by a sensor to be measured.

In the determination step, three of the measured values are
Changes in a plurality of measured values at the same rotational phase of the three-dimensional cam and at different positions in the rotational axis direction indicate a convex pattern,
In addition, when the convex pattern is within the allowable range, the result is judged to be acceptable, so that a three-dimensional cam that can completely prevent the cam surface from being damaged can be selected. Thus, as described above, it is possible to provide a three-dimensional cam capable of smoothly switching the opening / closing timing and the lift amount of the continuous intake valve or exhaust valve.

As set forth in claim 4, the allowable range may be a range set based on a linear pattern. The linear pattern is a pattern that is a reference for the tangent line of the conventional three-dimensional cam. If the linear pattern falls within the standard value based on the linear pattern, the internal combustion using the passed camshaft is determined. The engine or the like only needs to control the shaft moving mechanism as before, and there is no need to change the configuration on the control side. Therefore, the cost for changing the control system does not increase.

According to a fifth aspect of the present invention, as the above-described probe, a contact member having a planar measurement surface for contacting a cam surface of a three-dimensional cam, and the contact member is provided within the measurement surface. And a support member for swingably supporting the swing axis around the swing axis.

According to a sixth aspect of the present invention, in the three-dimensional cam profile measuring method using the three-dimensional cam profile measuring element, the three-dimensional cam profile measuring means can be translated in a direction perpendicular to the swing axis. While supporting the entire three-dimensional cam profile probe, and contacting the cam surface of the three-dimensional cam such that the swing axis is orthogonal to the rotation axis of the three-dimensional cam, the rotational phase of the three-dimensional cam is A movement process for changing the position in the rotation axis direction is performed, and the position of the support member or the contact member during the movement process is measured in association with the rotation phase of the three-dimensional cam and the position in the rotation axis direction. Thus, the three-dimensional cam can be configured as a three-dimensional cam profile measuring method characterized by measuring the cam profile.

Here, the whole three-dimensional cam profile probe according to claim 5 is supported so as to be able to move in parallel in a direction perpendicular to the pivot axis, and the pivot axis is perpendicular to the rotation axis of the three-dimensional cam. By contacting the cam surface of the three-dimensional cam with the cam follower, the three-dimensional cam profile gauge can be brought into contact with the cam surface of the three-dimensional cam in the same state as the cam follower. Then, in this contact state, a movement process for changing the rotation phase and the position in the rotation axis direction of the three-dimensional cam is performed. During this movement processing, the position of the support member or contact member of the three-dimensional cam profile gauge is measured in association with the rotation phase of the three-dimensional cam and the position in the direction of the rotation axis. Thus, the cam profile of the three-dimensional cam can be accurately measured.

According to a seventh aspect of the present invention, in the measuring step of the three-dimensional cam profile pass / fail determination method according to the third or fourth aspect, the measured value may be obtained by the measuring method according to the sixth aspect. , Accurate pass / fail judgment can be made.

According to a third aspect of the present invention, there is provided a three-dimensional cam profile measuring apparatus which supports the entire three-dimensional cam profile measuring element according to the fifth aspect so as to be able to translate in a direction orthogonal to a pivot axis and the pivot axis. Supporting means for urging the three-dimensional cam profile probe toward the cam surface of the three-dimensional cam so as to be orthogonal to the rotation axis of the three-dimensional cam to be measured;
Moving means for changing the rotation phase of the three-dimensional cam and the position in the direction of the rotation axis; and the position of the support member or the contact member during the processing of the movement means by changing the rotation phase of the three-dimensional cam and the direction of the rotation axis. And a measuring means for performing measurement in association with the position.

In this way, the three-dimensional cam profile gauge according to claim 5 is translated by the supporting means in a direction orthogonal to the swing axis, and the swing axis is the object of the three-dimensional cam to be measured. Since the three-dimensional cam profile gauge is urged toward the cam surface of the three-dimensional cam so as to be orthogonal to the rotation axis, the three-dimensional cam profile gauge is moved in the same state as the cam follower. It can be in contact with the cam surface.

The moving means changes the rotation phase and the position of the three-dimensional cam in the direction of the rotation axis, and during this processing, the measuring means changes the position of the support member or the contact member of the three-dimensional cam profile gauge. Since the measurement is performed in association with the rotation phase of the three-dimensional cam and the position in the direction of the rotation axis, the cam profile of the three-dimensional cam can be accurately measured.

Furthermore, as shown in claim 9, claim 8
Of the measured values obtained by the measuring means,
There is provided a determination unit that passes when a change in a plurality of measurement values at the same rotational phase of the three-dimensional cam and at different positions in the rotational axis direction indicates a convex pattern and the convex pattern is within an allowable range. For example, the apparatus can be configured as a device for selecting a three-dimensional cam that can completely prevent the cam surface from being damaged.

[0030] As described in claim 10, the allowable range may be a range set based on a linear pattern. The linear pattern is a pattern that is a reference for the tangent line of the conventional three-dimensional cam. If the linear pattern falls within the standard value based on the linear pattern, the internal combustion using the passed camshaft is determined. The engine or the like only needs to control the shaft moving mechanism as before, and there is no need to change the configuration on the control side. Therefore, the cost for changing the control system does not increase.

[0031]

[First Embodiment] FIG. 2 shows a valve characteristic control device applied to a vehicle engine (hereinafter, engine) 1 as an internal combustion engine. Here, a DOHC (double overhead cam) 4-valve type is assumed as the valve drive system.

First, an outline of the engine 1 will be described with reference to FIG. A plurality of cylinders 3 are provided in a cylinder block 2 constituting the engine 1, and a piston 4 is disposed in each cylinder 3. Each piston 4 is connected to a crankshaft 6 supported by a crankcase 5 by a connecting rod 7. The crankshaft 6 is provided with a crankshaft timing pulley 8.

An intake camshaft 10 is supported by a plurality of bearings (not shown) on a cylinder head 9 provided above the cylinder block 2 so as to be rotatable and movable in the axial direction. This intake side camshaft 10
, Two intake cams 11 are integrally provided for each cylinder 3. An exhaust camshaft 12 is rotatably supported on the cylinder head 9 by a plurality of bearings (not shown). The exhaust-side camshaft 12 is provided integrally with two exhaust-side cams 13 for each cylinder 3.

A camshaft timing pulley 14 and a shaft moving mechanism 15 are integrally provided on the intake side camshaft 10. The exhaust side camshaft 12 is provided with a camshaft timing pulley 16. Each of the camshaft timing pulleys 14 and 16 is connected to the crankshaft timing pulley 8 by the timing belt 1.
7 are connected. When the crankshaft 6 rotates, the intake camshaft 10 and the exhaust camshaft 12 are driven to rotate.

Each cylinder 3 is provided with two intake valves 18. And this intake valve 18
It is drivingly connected to the intake side cam 11 via valve lifters 19A and 19B, respectively. Each valve lifter 19
A and 19B are slidably supported in a lifter bore (not shown) provided in the cylinder head 9.

Each cylinder 3 has an exhaust valve 2
0s are provided two by two. Each exhaust side valve 20 is
The exhaust cam 13 is drivingly connected via a valve lifter 21. Each valve lifter 21 is also slidably supported in a lifter bore (not shown).

The intake cam 11 provided on the intake camshaft 10 is a three-dimensional cam having a cam surface 11a as shown in the perspective view of FIG. The solid line shown on the cam surface 11a indicates the tangent line 46. Intake side cam 1
The cam profile of the first cam surface 11a changes continuously and continuously from a low-lift cam profile 47 indicated by a broken line to a high-lift cam profile 48 indicated by a chain line. The above-mentioned tangent line 46 shown by a solid line connects the low lift side cam profile 47 and the high lift side cam profile 48. Note that the tangent line 46 shown in FIG. 1 is shown discretely with a rotation phase interval in order to indicate the direction, but actually exists on the entire surface of the cam surface 11a.

The tangent line 46 is different from the tangent line 546 of the conventional cam surface 540a shown in FIG.
The height of the intake-side cam 11 from the rotation axis A has a convex shape as shown in FIG. FIG. 3 exaggerates the protrusion amount. The height difference between the vertex of the convex central portion and the straight line connecting both ends is on the order of several μm.

The valve lifters 19A and 19B are formed in a cylindrical shape as shown in FIG. 4 (both valve lifters 19A and 19B have the same shape and only the valve lifter 19A is shown in FIG. 4). A guide member 23 is provided at 19a. The guide member 23 has a side surface 19.
a is press-fitted or welded into a fitting hole 19b formed on the side surface 19a. This guide member 23
Locks the valve lifter 19A non-rotatably in the lifter bore and slidably in the center axis direction.

A cam follower holder 24 is integrally formed on the upper surface 19C of the valve lifter 19A, and a cam follower 25 is supported on the cam follower holder 24 so as to be swingable in the width direction. FIG. 5 shows this cam follower 25.
Is shown in an enlarged manner.

The cam follower 25 has a flat sliding surface 25a which slides in contact with the cam surface 11a (FIG. 1) of the intake cam 11. FIG. 5A shows a vertical cross-sectional shape of such a cam follower 25, and FIG. 5B shows a side surface shape thereof.

On the other hand, the shaft moving mechanism 15 is a well-known mechanism for continuously and continuously displacing the intake camshaft 10 in the direction of the rotation axis A thereof through a hydraulic circuit (not shown).
That is, in FIG. 6 showing the periphery of the intake side cam 11 in an enlarged manner, the shaft moving mechanism 15 is such that the sliding surface 25a of the cam follower 25 shown by the two-dot chain line contacts the portion of the cam surface 11a with the smallest lift amount. The intake camshaft 10 is continuously and continuously displaced between a position and a position where the sliding surface 25a indicated by a solid line in FIG. 6 abuts on the portion of the cam surface 11a having the largest lift. The movable displacement amount is indicated by D in FIG.

Since the cam surface 11a of the intake side cam 11 is convex in the tangential direction as shown in FIG. 3, the contact state of the cam follower 25 with the sliding surface 25a is as shown in FIG. The edge portions 25b, 25c of 25 are not in contact with each other, but are in contact with an intermediate portion between both edge portions 25b, 25c.

Next, the operation of the valve characteristic control device configured as described above will be described. In the present embodiment, as described above, the upper surface 19C of the valve lifters 19A, 19B
Sliding surface 25 of cam follower 25 swingably supported
a is formed in a planar shape. On the other hand, the cam surface 11a of the intake side cam 11 on which the sliding surface 25a of the cam follower 25 slides is formed such that each tangent line 46 shown in FIG. 1 is convex.

The cam follower 25 slides along the shape between the low lift side cam profile 47 and the high lift side cam profile 48 of the cam surface 11a. During this sliding, the cam surface 11a of the intake side cam 11
Is designed such that its tangent line 46 is convex, so that even if there is a manufacturing error in the intake cam 11, the cam surface 11a of the intake cam 11 is not likely to be concave as in the prior art. . For this reason, as shown in FIG.
Edge portions 25b and 25c will not come into contact with cam surface 11a. That is, the contact with the cam surface 11a is limited only to the portion of the flat sliding surface 25a between the two edge portions 25b and 25c as shown in FIG.
The cam surface 11a is not damaged by the edge portions 25b and 25c of the cam follower 25.

In addition, a part of the sliding surface 25a that comes into contact is
The contact area with the cam surface 11a is smaller than the edge portions 25b and 25c.
Larger than when contacting with As a result, the contact surface pressure is reduced, and wear of the cam surface 11a due to contact with the sliding surface 25a of the cam follower 25 is also suppressed.

According to the embodiment described above, the following effects can be obtained. In other words, the cam follower 25 abuts on the cam surface 11a, not on the edge portions 25b and 25c, but on the intermediate planar sliding surface 25a.
No streaks are formed on 1a.

. Moreover, the sliding surface 25 of the cam follower 25
The contact area between a and the cam surface 11a of the intake side cam 11 is larger than in the conventional case where the edge portions 25b and 25c contact the cam surface 11a. This also suppresses abrasion of the cam surface 11a due to contact with the sliding surface 25a of the cam follower 25.

Therefore, when the intake side cam 11 moves in the direction of its rotation axis, the edge portion 2 of the cam follower 25
Smooth switching of the opening / closing timing of the intake valve 18 and the lift amount can be maintained without causing the striations 5b and 25c to be caught by the striations.

[Second Embodiment] Next, the first embodiment will be described.
The following describes a three-dimensional cam profile measuring device that can measure the cam profile of the cam surface 11a of the intake cam 11 and select the cam surface 11a with a tangential shape that is reliably convex. The three-dimensional cam profile gauge used in the three-dimensional cam profile measuring device, the three-dimensional cam profile measuring method using the three-dimensional cam profile measuring device, and the three-dimensional cam profile pass / fail determination method will also be described below.

FIG. 8 is a block diagram showing the configuration of the three-dimensional cam profile measuring device 100. As shown in FIG. The three-dimensional cam profile measuring device 100 includes a measurement control circuit 102, a rotary driving device 104, a linear driving device 106, a moving position / rotational phase measuring device 108, and a cam profile contact measuring unit 11.
0, an external storage device 112, a display device 114, and a printer 116. In addition, although not shown, a communication circuit with a host computer is provided.

The measurement control circuit 102 includes a CPU,
It is configured as a computer system having a ROM, a RAM, an input / output interface, a bus line, an internal storage device, and the like.
Based on the program stored in the second or the like, the CPU inputs detection data from the movement position / rotational phase measurement device 108 or the cam profile contact measurement unit 110 via the input / output interface and performs necessary arithmetic processing, The calculation result, here, the result of obtaining the cam profile of the cam surface 11a of the intake cam 11 is stored in the external storage device 112 via the input / output interface, displayed on the display device 114, or displayed on the printer 116. Or print.

The rotation driving device 104 is composed of a stepping motor, a servomotor, and the like, and adjusts the rotation phase of the intake valve camshaft 10 based on an instruction signal from the measurement control circuit 102 when measuring the cam profile. ing.

The linear driving device 106 is constituted by a linear moving mechanism by a motor using a linear solenoid or a ball screw, and based on an instruction signal from the measurement control circuit 102, the linear driving device 106 in the rotation axis direction of the camshaft 10 for the intake valve. The position is being adjusted.

The moving position / rotational phase measuring device 108 includes a rotational position sensor using a synchro, a resolver, a rotary encoder or the like, and a linear position sensor using a potentiometer, a differential transformer or a scale. And linear drive 106
By measuring an accurate rotation phase and an accurate position in the rotation axis direction on the camshaft 10 being rotated and moved by
It is transmitted to the measurement control circuit 102 as a measurement signal.

The cam profile contact measuring section 110 includes a three-dimensional cam profile probe 120 described later and a linear position sensor using a potentiometer, a differential transformer or a scale. The cam profile contact measuring section 110 supports the three-dimensional cam profile gauge 120 so as to be able to move in parallel along a moving axis G described later and to urge it toward the intake side cam 11 by its parallel movement supporting section 110a. doing.

As a result, the cam profile contact measuring section 110 converts the three-dimensional cam profile
The three-dimensional cam profile gauge 120 is brought into contact with the cam surface 11a of the intake cam 11 present on the camshaft 10 being rotated and moved by the rotary drive device 104 and the linear drive device 106, and the height of the cam surface 11a is raised. 3D cam profile gauge 120
Is measured by a linear position sensor and transmitted to the measurement control circuit 102 as a measurement signal.

Next, the three-dimensional cam profile gauge 120
Will be described. FIG. 9 shows a perspective view of the three-dimensional cam profile gauge 120. The three-dimensional cam profile probe 120 includes a contact member 122 and the contact member 122.
At both ends.
As shown in the perspective view of FIG. 10 (however, the contact member 122 is arranged upside down with respect to FIG. 9), the contact member 122 has a cylindrical rod shape and has shaft portions 126 and 128 at both ends.
The contact member 122 is supported by the two arm portions 130 and 132 of the support member 124 so as to be swingable about the swing axis F at the shaft portions 126 and 128.

The central portion 122a of the contact member 122 has a shape of only one half cut in a plane including the pivot axis F, and is formed flat except for a central area including the pivot axis F. I have. As a result, the measurement surface 122b including the pivot axis F is entirely formed in the central portion 122a of the contact member 122. The central portion 122a is made of cemented carbide, and the measurement surface 122b is finished with extremely high surface accuracy.

The support member 124 has a base 134 for supporting the two arms 130 and 132 described above.
At the base 134, the three-dimensional cam profile gauge 120
The whole is prevented from rotating around a movement axis G orthogonal to the swing axis F, so as to be able to move in parallel in the direction of the movement axis G, and urged in the direction of the intake side cam 11, The cam profile contact measurement unit 110 is supported by the translation support unit 110a.

At the time of measurement, as shown in FIG.
2 so that the swing axis F is orthogonal to the rotation axis A of the intake cam 11, and the three-dimensional cam profile gauge 120 is urged toward the intake cam 11 along the movement axis G, so that the cam surface 11a The measurement surface 122b of the contact member 122 abuts on the support member 1
24 displacement is measured.

This measurement process is performed by the measurement control circuit 102 as shown in the flowcharts of FIGS. It is assumed that the camshaft 10 is manually or automatically set in the three-dimensional cam profile measuring device 100 as shown in FIG.

First, when the measurement process is started, an initial state is set (S100). That is, the rotation driving device 104 is driven to dispose the camshaft 10 at the rotation phase at the start of measurement, and the linear driving device 106 is driven to move the camshaft 10 to the measurement start position in the rotation axis direction of the camshaft 10. Deploy.

Next, an interrupt activation of the detection routine is set (S110). This detection routine is interrupted every time the camshaft 10 rotates for the measurement interval (for example, 0.5 °).
By setting the interrupt activation at
Each time the camshaft 10 rotates for the measurement interval based on the detection signal of the rotation phase measuring device 108, the measurement control circuit 102 executes the interrupt processing shown in FIG.

In this detection routine, the following processing is performed. That is, as shown in FIG. 14, first, the rotation phase of the camshaft 10 is calculated based on the number of interruptions from the rotation start position and stored in the RAM inside the measurement control circuit 102 or the external storage device 112 (S112).

Next, the position of the camshaft 10 in the rotation axis direction is read from the detection signal of the moving position / rotational phase measuring device 108 at this time, and is correlated with the rotation phase data obtained in the immediately preceding step S112. External storage device 11
2 (S114).

Then, the cam profile contact measuring section 11
The position of the cam surface 11a of the intake cam 11 is read from the detection signal of 0 and stored in the RAM or the external storage device 112 in association with the rotational phase data and the rotational axis direction position data obtained in the immediately preceding steps S112 and S114. (S11
6).

When the processing of the detection routine is completed as described above, the detection routine waits until the next interruption is performed. In FIG. 12, after the start of the detection routine is set in step S110, the rotation driving device 10
4 outputs an instruction signal from the measurement control circuit 102, thereby starting rotation of the camshaft 10 (S12).
0). Therefore, when the camshaft 10 is rotated, the movement position / rotational phase measuring device 108 informs the measurement control circuit 102 of the state in which the rotational phase of the camshaft 10 changes every moment, and also performs a detection routine interrupt. Every time the rotation is performed by the angle, the measurement control circuit 102 executes the detection routine shown in FIG. 14 to obtain the above-described measurement data.

In the process following step S120, it is determined whether the camshaft 10 has completed one revolution (S13).
0), the current state continues until the camshaft 10 makes one rotation ("NO" in S130), and the cam surface 11a of the intake-side cam 11 for each interruption rotation phase at one rotation axis direction position. Height continues to be measured.

If the camshaft 10 makes one rotation (S13)
0 and “YES”), the measurement control circuit 102 stops the rotation of the camshaft 10 (S140). Next, it is determined whether the measurement has been completed (S150). This determination is for determining whether or not the above-described measurement processing for one rotation has been completed at all measurement positions in the rotation axis direction of the camshaft 10.

If the measurement has not been completed for all the measurement positions in the rotation axis direction ("NO" in S150), then the camshaft 10 is set to a new measurement position in the rotation axis direction and set to the reference rotation phase. (S160), the step S120 is executed again, and the rotation of the camshaft 10 is started. Therefore, the process of executing the detection routine every time the interruption angle is rotated is continued.

However, this time, since the position in the rotation axis direction has changed, the measurement for one rotation of the camshaft 10 at the new position in the rotation axis direction is performed. Thereafter, as long as there is an unmeasured rotation axis direction position, a new rotation axis direction position is set, and the above-described processing of steps S120 to S160 is repeated.

When the measurement for one rotation is completed at all positions of the intake cam 11 to be measured in the direction of the rotation axis ("YES" in S150), the interruption of the detection routine is set (step 150). S170) The execution of the interrupt processing of the detection routine shown in FIG. 14 is prohibited.

At this time, the measurement data is obtained as representing the cam profile of the entire cam surface 11a of one intake-side cam 11. For example, it is obtained as shown in FIG. FIG. 15 shows three representative cam profiles. That is, the cam profile S1 at the one limit position in the direction of the rotation axis where the cam nose is the highest is represented by a dashed line, the cam profile S3 at the other limit position in the direction of the rotation shaft where the cam nose is the lowest is represented by the broken line, and the intermediate position is shown. Is represented by a solid line. In practice, this intermediate cam profile has also been measured.

Next, a process for evaluating the data measured in this way to determine whether or not the intake-side cam 11 is acceptable is performed (S180). In this pass / fail determination, the cam profile contact measurement unit 11 in the same rotational phase of the camshaft 10 is used.
It is determined whether the measured value of 0 indicates a convex pattern in the direction of the rotation axis, and whether the convex pattern is within an allowable range. This determination is made for all measured rotational phases.

For example, as shown in FIGS. 1 and 15,
It is assumed that the height of the cam surface 11a is measured at four different rotational axis positions a, b, c, and d in the same rotational phase θa. The measured values at the respective positions a, b, c and d are shown in the graph of FIG.

The horizontal straight line shown in FIG. 16 indicates the theoretical line T when the tangent line 46 is a straight line. The measured value is represented by a difference from the theoretical line T. Further, the range of the standard value with respect to the theoretical line T is set on the plus side and the minus side, respectively.

As can be seen from FIG. 16, the cam surfaces 11a at the positions a, b, c, d in the direction of the rotational axis are located at positions b, c in the direction of the rotational axis intermediate from the positions a, d at the ends. Is higher, and the height distribution pattern of the cam surface 11a at the rotation phase θa has a convex shape.

Further, the positions a, b, c and d in the rotation axis direction are all within the standard values. That is, the distribution pattern of the rotational axis positions a, b, c, and d is within the allowable range. As described above, if the measured value of the height of the cam surface 11a at the rotational axis direction position has a convex shape at the same rotational phase θa, and all the rotational phases of the intake cam 11 are convex, the process proceeds to step S180. In the determination process, it is determined to be passed.

Therefore, in the next pass / fail judgment (S190), it is judged as pass and the camshaft 1
It is determined whether or not the intake cam 11 to be measured next is above 0 (S200). Intake side cam 1 not yet measured
If there is 1 ("NO" in S200), the rotation driving device 10
4 and the driving of the linear drive device 106, the contact member 122 of the three-dimensional cam profile gauge 120 is moved relatively to the initial measurement reference position of the cam surface 11a of the next intake side cam 11, and the measurement surface 122b is newly set. Cam surface 11a
(S210). Then, starting from the processing in step S110, the above-described series of processing (step S1
In step 00 to step S160), the cam profile of the next intake cam 11 is measured.

As long as it is determined to be acceptable in the processing in steps S180 and S190 and it is determined in step S200 that an unmeasured intake-side cam 11 exists, the above-described series of processing (steps S100 to S100) is performed. S16
Repeat 0).

As a result, the cam profiles of all the intake-side cams 11 on the camshaft 10 are measured, and if it is determined that all the intake-side cams 11 are acceptable in steps S180 and S190, the next step is In S200, there is no unmeasured intake cam 11 ("YES" in S200), and then a pass process is executed (S220). In this pass process, for example, the display of “pass” is displayed on the display device 11 together with the inspection number.
4 or prints the data on the printer 116 or stores the pass result together with the test number in the external storage device 112. Further, the data indicating the success may be transferred to a host computer which is connected to the measurement control circuit 102 in a signal manner.

Further, even once, steps S180, S1
If it is determined to be unacceptable at 90, that is, the determination is made for all rotation phases of the intake cam 11, and for example, the distribution pattern of the rotational axis positions a, b, c, d is theoretically as shown in FIG. When the position a on the rotational axis direction side with respect to the line T is higher, when the distribution pattern is concave as shown in FIG. 18, or when the distribution pattern is convex as shown in FIG. If the measured values (here, the positions a and c in the rotation axis direction) are out of the standard values, 1
If it is found even once, rejection is determined in step S190, and rejection processing is executed (S230).
In this rejection processing, for example, the display of “failed” is displayed on the display device 114 together with the inspection number, printed on the printer 116, or the external storage device 11.
A process of storing the rejection result together with the inspection number in 2 is performed. Further, the data indicating the rejection may be transferred to a host computer which is connected to the measurement control circuit 102 in a signal manner.

Step S220 or Step S230
When this process is completed, this measurement processing routine is completed.
Then, after the next camshaft 10 is set in the three-dimensional cam profile measuring device 100 by the measurer, if a measurement start instruction is given through a switch or the like provided in the measurement control circuit 102, the measurement is performed again as shown in FIG. 14 are executed, and the measurement of the cam profiles of all the cams on the next camshaft 10 and the determination of pass / fail are performed.

Of the above-described processing, steps S100 to S160, step S210 and step S1
The processing from step 12 to step S116 corresponds to a measuring step and a processing as a measuring means. Steps S180 to S200, S220, and S230 correspond to a determination step and a process as a determination unit.

The cam profile contact measuring section 110
The parallel movement support portion 110a corresponds to a support means, the rotation drive device 104 and the linear drive device 106 correspond to a movement device, and the movement position / rotational phase measurement device 108, the cam profile contact measurement unit 110, and the measurement control circuit 102 It corresponds to a measuring means.

According to the embodiment described above, the following effects can be obtained. The three-dimensional cam profile gauge 120 is the intake cam 1
A flat measuring surface 12 for contacting the first cam surface 11a
2b, and the contact member 122
And a support member 124 that supports the measurement surface 122b in a swingable manner about a pivot axis F existing in the measurement surface 122b. Therefore, the inclination of the cam surface 11a of the intake side cam 11, which is a three-dimensional cam, is measured. The swing axis F of the contact member 122 can always contact the measurement position on the cam surface 11a. Therefore, the intake side cam 1
1. The entire cam profile can be precisely measured.

In particular, when the cam surface 11a of the intake side cam 11 is convex as described above, the convex state can be detected accurately, and it can be accurately determined whether or not the tangent line is convex. . For this reason, it is possible to accurately determine whether or not the intake side cam 11 is acceptable if the tangent is convex and conforms to the standard, and the intake side cam 1 used in the first embodiment is determined.
1, that is, it is possible to provide a three-dimensional cam capable of smoothly switching the opening / closing timing and lift amount of a continuous intake valve or exhaust valve.

The three-dimensional cam profile measuring device 100 supports the entire three-dimensional cam profile gauge 120 so as to be able to translate in the direction of the movement axis G orthogonal to the swing axis F, and the swing axis F is measured. The cam surface 11a of the intake-side cam 11 is orthogonal to the rotation axis A of the target intake-side cam 11.
And a rotation driving device 104 for changing the rotational phase of the intake cam 11 and the position of the intake cam 11 in the direction of the rotation axis A.
And the linear drive 106 and the rotary drive 10
4 and support member 124 of three-dimensional cam profile gauge 120 during processing by linear drive 106
Of the intake side cam 1 using the moving position / rotational phase measuring device 108 and the cam profile contact measuring unit 110.
And a measurement control circuit 102 for performing measurement in association with one rotation phase and a position in the direction of the rotation axis A.

For this reason, the three-dimensional cam profile gauge 120 can be translated in the direction of the movement axis G orthogonal to the swing axis F.
The whole is supported, and the swing axis F is the rotation axis A of the intake side cam 11.
In a state in which the cam surface 11a of the intake cam 11 is in contact with the cam surface 11a so as to be orthogonal to the above, a moving process for changing the rotation phase of the intake cam 11 and the position in the direction of the rotation axis A is performed. A three-dimensional cam profile for measuring the cam profile of the intake-side cam 11 by measuring the position of the support member 124 of the cam profile gauge 120 in association with the rotational phase of the intake-side cam 11 and the position in the direction of the rotation axis A. A measuring method can be performed.

As described above, in the parallel movement supporting portion 110a,
The three-dimensional cam profile gauge 120 is moved in parallel in the direction of the movement axis G orthogonal to the swing axis F, and the swinging axis F is orthogonal to the rotation axis A of the intake cam 11 to be measured. Since the three-dimensional cam profile gauge 120 is biased toward the cam surface 11a of the side cam 11, the three-dimensional cam profile gauge 120 is maintained in the same state as the cam follower.
Can contact the cam surface 11a of the intake-side cam 11.

The rotary drive unit 104 and the linear drive unit 106 change the rotation phase of the intake cam 11 and the position in the direction of the rotation axis A, and during this processing, the movement position / rotational phase measurement unit 108 and the cam profile Using the contact measurement unit 110, the measurement control circuit 102 determines the position of the support member 124 of the three-dimensional cam profile gauge 120,
Since the measurement is performed in association with the rotation phase of the intake cam 11 and the position in the direction of the rotation axis A, the cam profile of the intake cam 11 can be accurately measured.

Further, the moving position / rotational phase measuring device 10
8. Among the measured values obtained by the cam profile contact measuring section 110 and the measurement control circuit 102, the intake side cam 11
A change of a plurality of measured values at different positions in the direction of the rotation axis A in the same rotational phase indicates a convex pattern, and when the convex pattern is within a standard value, the judgment process is judged to be a pass. Since the operation is performed by the 102, the apparatus can be configured as a device for selecting the intake side cam 11 having a shape capable of completely preventing the cam surface 11a from being damaged. As a result, as described above, it is possible to provide a three-dimensional cam capable of smoothly switching the opening / closing timing and lift amount of the continuous intake valve.

Further, in the present embodiment, when the pass / fail of the cam profile having the convex tangent line 46 is determined, the one that falls within the standard value based on the theoretical line T corresponding to the straight tangent line is determined to be acceptable. . Therefore, the engine 1 using the camshaft 10 that has been accepted in the present embodiment only needs to control the shaft moving mechanism 15 as before, and does not need to change the configuration on the control side. Therefore, even if the three-dimensional cam selected by the above-described three-dimensional cam profile measuring device 100 is adopted as the intake-side cam 11, the cost for changing the control system does not increase.

[Other Embodiments] The present invention is not limited to the above-described embodiments, but may be configured as follows.

In each of the above embodiments, since the shaft moving mechanism 15 is provided on the camshaft 10 for the intake valve, an example in which the tangent line 46 is formed in the cam surface 11a of the intake cam 11 in a convex shape. As described above, the exhaust-side camshaft 12 is provided with a shaft moving mechanism,
If the exhaust side cam 13 is configured as a three-dimensional cam,
Embodiments 1 and 2 are also applied to the exhaust cam 13. Further, a shaft moving mechanism is provided for both the intake side camshaft 10 and the exhaust side camshaft 12, and both the intake side cam 11 and the exhaust side cam 13 are three-dimensional cams.
It may be configured as a device that controls both valve characteristics.

Since the three-dimensional cam profile measuring device 100 can measure the cam profile even if it is not a three-dimensional cam, the measurement of the cam surface of a normal cam (the cam surface of the exhaust side cam 13 in the first embodiment) is performed. Since there is no need to provide a cam profile measuring device for each type of cam, it is advantageous in terms of equipment.

In the first embodiment, the intake cam 11 is provided integrally with the intake camshaft 10, and the shaft moving mechanism 15 displaces the intake cam 11 together with the intake camshaft 10 in the axial direction. And On the other hand, the intake camshaft 10 may not be moved, and only the intake cam 11 may be displaced in the same direction. In this case, the same operation and effect as in the first embodiment can be obtained.

In the first embodiment, an example in which the present invention is applied to an engine having four valves per cylinder has been described. However, the present invention is not limited to this. For example, two valves per cylinder or six valves per cylinder are used.
The present invention may be applied to an engine having a number of valves such as a valve and eight valves.

In the first embodiment, two intake cams 1
1 shows an example in which the present invention is applied to a valve characteristic control device configured to drive the valve lifters 19A and 19B. However, the present invention is not limited to this. For example, a valve having a configuration in which one intake cam 11 drives two valve lifters is used. It can also be applied to a characteristic control device.

In the second embodiment, the movement position / rotational phase measuring device 108 detects the movement position and the rotation phase in the direction of the rotation axis A, and the cam surface 11a of the intake side cam 11 is detected.
However, if the rotary driving device 104 and the linear driving device 106 can drive with high accuracy, the moving position / rotational phase measuring device 108 is unnecessary, and the rotational driving It is possible to obtain an accurate cam profile by associating the movement position command value and the rotation phase command value in the direction of the rotation axis A to the device 104 and the linear drive device 106 with the height of the cam surface 11a of the intake cam 11. it can. In this case, the cam profile contact measurement unit 110 and the measurement control circuit 102 correspond to a measurement unit.

In the second embodiment, the contact member 122 supported by the support member 124 is used as the three-dimensional cam profile gauge 120, but the valve lifter 19A shown in FIG. Configuration may be the same as That is, instead of supporting the contact member 122 pivotally, the contact member 122 may be supported in a manner similar to the cam follower holder 24 so as to be swingable in the width direction.

In the second embodiment, in the measuring step, the height of the cam surface 11a is directly obtained. However, the height state of the cam surface 11a may be determined without obtaining the height. A physical quantity corresponding to the height of the cam surface 11a may be obtained as a measured value. For example, a reference point may be provided outside the intake side cam 11 and measured as angle and distance data from the reference point.
It may be obtained as a voltage output from a sensor to be measured or another physical quantity.

[0104]

According to the three-dimensional cam of the first aspect,
The portion where the sliding surface of the cam follower contacts does not have a linear shape as in the related art, but has a convex height distribution.
For this reason, even if there is a manufacturing error of the three-dimensional cam, the cam surface of the three-dimensional cam does not become concave as in the related art, so that only the edge portion can be prevented from contacting the cam surface, and the cam surface can be prevented. No streak is formed. Further, the same applies to the case where the height distribution is accurately measured to be convex as described later and judgment and selection are performed.

Therefore, when the three-dimensional cam moves in the direction of its rotation axis, the edge of the cam follower does not catch on the streak, and the opening / closing timing of the intake valve and the exhaust valve and the smooth switching of the lift amount are maintained. be able to.

Further, as described in claim 2, by being attached to the camshaft, the intake valve or the exhaust valve of the internal combustion engine is driven to open and close, and the intake valve is moved based on the movement of the camshaft in the rotation axis direction. The present invention is applied to an internal combustion engine by being configured as a three-dimensional cam characterized by changing the opening / closing characteristics of a valve or the exhaust valve, and smoothly switches the opening / closing timing and lift amount of a continuous intake valve or exhaust valve. be able to.

According to a third aspect of the present invention, the measuring step includes, for example, contacting a probe similar to a cam follower with a cam surface to thereby change the position of the probe similar to the cam follower. At
The height of the cam surface, that is, the distance from the rotation axis of the three-dimensional cam can be obtained.

As a judgment step, three of the measured values
Changes in a plurality of measured values at the same rotational phase of the three-dimensional cam and at different positions in the rotational axis direction indicate a convex pattern,
In addition, if the convex pattern is within the allowable range, and the test is passed, a three-dimensional cam that can completely prevent the cam surface from being damaged can be selected. Thus, as described above, it is possible to provide a three-dimensional cam capable of smoothly switching the opening / closing timing and the lift amount of the continuous intake valve or exhaust valve.

As described in claim 4, when a range set with a linear pattern as a reference is used as the allowable range, such a linear pattern is a conventional three-dimensional pattern.
This is the reference pattern of the dimensional cam, which means that the conventional allowable range is used. Therefore, an internal combustion engine or the like using a three-dimensional cam that has been accepted can perform the conventional control of the shaft moving mechanism by accepting the one that falls within the standard value based on the linear pattern as a reference. It is not necessary to change the configuration on the control side. Therefore, the cost for changing the control system does not increase.

According to a fifth aspect of the present invention, as the above-described probe, a contact member having a planar measurement surface for contacting the cam surface of a three-dimensional cam, and the contact member is present in the measurement surface. A three-dimensional cam profile gauge having a support member that swingably supports around a swing axis. The above-described measurement can be performed, and the above-described effects can be obtained. be able to.

Further, as described in claim 6, the three-dimensional cam profile measuring method using the three-dimensional cam profile measuring element is capable of parallel movement in a direction orthogonal to the swing axis. The three-dimensional cam profile is supported in the same state as the cam follower by supporting the whole of the three-dimensional cam profile and contacting the cam surface of the three-dimensional cam such that the swing axis is orthogonal to the rotation axis of the three-dimensional cam. The probe can be brought into contact with the cam surface of the three-dimensional cam. Therefore, in this contact state, it is possible to perform a moving process for changing the rotational phase and the position of the three-dimensional cam in the rotation axis direction, and to support or contact the three-dimensional cam profile gauge during the moving process. The position of
The measurement can be performed in association with the rotation phase of the three-dimensional cam and the position in the rotation axis direction. Thus, the cam profile of the three-dimensional cam can be accurately measured.

As described in claim 7, in the measurement step of the three-dimensional cam profile pass / fail determination method according to claim 3 or 4, when the measured value is obtained by the measurement method according to claim 6, An accurate pass / fail judgment can be made.

In the three-dimensional cam profile measuring device according to the eighth aspect, the three-dimensional cam profile measuring element according to the fifth aspect is translated by a supporting means in a direction perpendicular to the swing axis, and Since the three-dimensional cam profile probe is urged toward the cam surface of the three-dimensional cam so that the swing axis is orthogonal to the rotation axis of the three-dimensional cam to be measured, it is in the same state as the cam follower. The three-dimensional cam profile probe can be brought into contact with the cam surface of the three-dimensional cam.

The moving means changes the rotation phase and the position of the three-dimensional cam in the direction of the rotation axis, and during this processing, the measuring means changes the position of the support member or contact member of the three-dimensional cam profile gauge. Since the measurement is performed in association with the rotation phase of the three-dimensional cam and the position in the direction of the rotation axis, the cam profile of the three-dimensional cam can be accurately measured.

According to a ninth aspect of the present invention, in the configuration of the eighth aspect, a plurality of measured values obtained by the measuring means at the same rotational phase of the three-dimensional cam and at different positions in the rotational axis direction are different from each other. If a change in the measured value indicates a convex pattern, and if the convex pattern is within an allowable range, and a determination unit is provided for passing, a three-dimensional cam that can completely prevent scratches on the cam surface is provided. It can be configured as a sorting device.

In the case where the range set with reference to the linear pattern is used as the allowable range used by the judging means of the three-dimensional cam profile measuring device, such a linear pattern may be used. Is a pattern which is a reference of the conventional three-dimensional cam, and the conventional allowable range is used. Therefore, an internal combustion engine or the like using a three-dimensional cam that has been accepted can perform the conventional control of the shaft moving mechanism by accepting the one that falls within the standard value based on the linear pattern. It is not necessary to change the configuration on the control side. Therefore, the cost for changing the control system does not increase.

[Brief description of the drawings]

FIG. 1 is a perspective view for explaining a shape of a cam surface of an intake-side cam according to a first embodiment.

FIG. 2 is a perspective view of a main part of a valve characteristic control device applied to the vehicle engine according to the first embodiment.

FIG. 3 is a graph for explaining a shape of a tangent line on a cam surface of an intake cam in the first embodiment.

FIG. 4 is a perspective view of a valve lifter according to the first embodiment.

FIG. 5 is an explanatory diagram of a shape of a cam follower according to the first embodiment.

FIG. 6 is an explanatory diagram of a configuration around an intake-side cam according to the first embodiment.

FIG. 7 is a diagram illustrating a contact state between a cam surface of an intake-side cam and a cam follower according to the first embodiment.

FIG. 8 is a configuration block diagram of a three-dimensional cam profile measurement device according to a second embodiment.

FIG. 9 is a perspective view of a three-dimensional cam profile gauge according to the second embodiment.

FIG. 10 is a perspective view of a contact member of a three-dimensional cam profile gauge according to the second embodiment.

FIG. 11 is a perspective view showing a contact state between a contact member of a three-dimensional cam profile gauge and an intake cam in the second embodiment.

FIG. 12 is a flowchart of a measurement processing routine executed by the three-dimensional cam profile measurement device according to the second embodiment.

FIG. 13 is a flowchart of a measurement processing routine executed by the three-dimensional cam profile measurement device according to the second embodiment.

FIG. 14 is a flowchart of a detection routine executed by the three-dimensional cam profile measurement device according to the second embodiment.

FIG. 15 is a graph illustrating an example of a measurement result performed by the three-dimensional cam profile measurement device according to the second embodiment.

FIG. 16 is a graph illustrating an example of data used by the three-dimensional cam profile measurement device according to the second embodiment to determine the acceptability of an intake cam.

FIG. 17 is a graph illustrating an example of data used by the three-dimensional cam profile measurement device according to the second embodiment to determine the acceptability of an intake cam.

FIG. 18 is a graph showing an example of data used by the three-dimensional cam profile measurement device according to the second embodiment to determine the acceptability of an intake cam.

FIG. 19 is a graph showing an example of data used by the three-dimensional cam profile measurement device according to the second embodiment to determine the acceptability of an intake cam.

FIG. 20 is a main part configuration diagram of a valve characteristic control device applied to a vehicle engine in a conventional form.

FIG. 21 is an explanatory diagram of a shape of a cam follower in a conventional embodiment.

FIG. 22 is an explanatory diagram of a contact state between a cam follower and a three-dimensional cam in a conventional embodiment.

FIG. 23 is a perspective view for explaining the shape of a cam surface of a three-dimensional cam in a conventional embodiment.

FIG. 24 is an explanatory diagram of a contact state between a cam follower and a three-dimensional cam in a conventional embodiment.

[Explanation of symbols]

A: rotating shaft, F: swinging shaft, G: moving shaft, 1: vehicle engine, 2 ... cylinder block, 3 ... cylinder, 4 ... piston, 5 ... crankcase, 6 ... crankshaft,
7 ... connecting rod, 8 ... crankshaft timing pulley, 9 ... cylinder head, 10 ... intake side camshaft,
11 intake cam, 11a cam surface, 12 exhaust camshaft, 13 exhaust cam, 14 camshaft timing pulley, 15 shaft movement mechanism, 16 camshaft timing pulley, 17 timing belt, 1
8 ... intake valve, 19A, 19B ... valve lifter, 19
C: Top surface of valve lifter, 19a: Side surface, 19b: Fitting hole, 20: Exhaust valve, 21: Valve lifter, 23 ...
Guide member, 24: cam follower holder, 25: cam follower, 25a: sliding surface, 25b, 25c: edge portion, 4
6 ... tangent line, 47 ... low lift side cam profile, 48 ...
High lift side cam profile, 100: three-dimensional cam profile measuring device, 102: measurement control circuit, 104:
Rotary drive device 106 Linear drive device 108 Moving position / rotational phase measurement device 110 Cam profile contact measurement unit 110a Parallel movement support unit 112 External storage device 114 Display device 116 Printer Reference numeral 120: three-dimensional cam profile probe, 122: contact member, 122a: central portion, 122b: measurement surface, 12
4. Supporting member, 126, 128 Shaft, 130, 132
... arm part, 134 ... base part.

Claims (10)

[Claims] 1. A three-dimensional cam having a cam surface with which an oscillating cam follower abuts, and a cam profile continuously changing in a rotation axis direction, wherein the three-dimensional cam has the same rotational phase. A three-dimensional cam, wherein a height distribution in a rotation axis direction of a contact position between the cam follower and the cam surface is convex. 2. By being attached to a camshaft,
2. An opening / closing drive of an intake valve or an exhaust valve of an internal combustion engine, and changing an opening / closing characteristic of the intake valve or the exhaust valve based on a movement of the camshaft in a rotation axis direction. 3D cam. 3. The method according to claim 1, wherein a height of the cam surface with respect to a rotation axis of the three-dimensional cam or a physical quantity corresponding to the height is measured. And a change in a plurality of measured values at the same rotational phase of the three-dimensional cam and at different positions in the rotation axis direction indicates a convex pattern among the measured values determined in the measuring step, And a step of determining whether the convex pattern is acceptable if the convex pattern is within an allowable range. 4. The method according to claim 3, wherein the allowable range is a range set based on a linear pattern. 5. A contact member having a planar measurement surface for contacting a cam surface of a three-dimensional cam, and the contact member is swingably supported around a swing axis existing in the measurement surface. A three-dimensional cam profile gauge, comprising: a support member; 6. The three-dimensional cam profile probe according to claim 5, which is capable of being translated in a direction perpendicular to the swing axis, so that the swing axis is orthogonal to the rotation axis of the three-dimensional cam. Performing a moving process of changing a rotation phase and a position of the three-dimensional cam in a rotation axis direction in a state of being brought into contact with a cam surface of the three-dimensional cam; A three-dimensional cam profile measuring method, wherein a position is measured in association with a rotational phase of the three-dimensional cam and a position in a rotation axis direction to measure a cam profile of the three-dimensional cam. 7. The three-dimensional cam profile pass / fail determination method according to claim 3, wherein a measurement value is obtained by the measurement method according to claim 6 in the measuring step. 8. The rotation axis of a three-dimensional cam that supports the entire three-dimensional cam profile probe according to claim 5, and is capable of moving in parallel in a direction orthogonal to the oscillation axis. Supporting means for urging the three-dimensional cam profile probe toward the cam surface of the three-dimensional cam so as to be perpendicular to the moving direction; and moving means for changing the rotational phase and the position of the three-dimensional cam in the rotational axis direction. Measuring means for measuring the position of the support member or the contact member during the processing of the moving means in association with the rotational phase of the three-dimensional cam and the position in the direction of the rotational axis. 3D cam profile measuring device. 9. The apparatus according to claim 8, wherein, of the measured values obtained by said measuring means, a plurality of measured values at the same rotational phase of said three-dimensional cam and at different positions in the rotational axis direction. A three-dimensional cam profile measuring device, comprising: a determination unit that passes when the change indicates a convex pattern and the convex pattern is within an allowable range. 10. The three-dimensional cam profile measuring device according to claim 9, wherein the allowable range is a range set based on a linear pattern.