JPH11166423A - Camshaft for cross head type large 2-cycle internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a camshaft wherein unexpected wearing of a cam disk and a tappet roller is greatly reduced. SOLUTION: A camshaft 1 in an internal combustion engine includes several cam disks 10 and 11 having related tappet rollers for driving a driving wheel 9 and a piston or a valve driving body in a combustion pump in a reciprocating state. The camshaft 1 includes a vibration damper composed of one or more cam disks 10 and 11 having related spring load type tappet rollers arranged in positions separated from the driving wheel 9. These cam disks 10 and 11 have vibration damping areas displaced from a circular trajectory, and thus a force from the load type tappet roller is changed during operation, and influence is given to the camshaft 1 by torque for damping or compensating for harmony twisting vibration of one or more in the order of sixteen.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large two-stroke internal combustion engine of the crosshead type, comprising a drive wheel driven synchronously with a crankshaft of an engine via a gear or a chain drive, and The invention relates to a camshaft of an internal combustion engine comprising a number of cam disks with associated tappet rollers for driving a piston or valve driver in a pump in a reciprocating motion and a drive damper, the drive damper comprising:
At least one cam disk having an associated spring-loaded tappet roller disposed remote from the drive wheels, the at least one cam disk of the vibration damper having an outer periphery cooperating with the associated tappet roller; ,
A vibration damping region, which is deviated from the circular track so that the force from at least one spring-loaded tappet roller can be applied to the camshaft with varying torque. Affect.

[0002]

2. Description of the Related Art U.S. Pat.
A camshaft in an internal combustion engine is described, in which case the vibration damper is integrated with the drive wheel of the camshaft,
The dynamic load applied to the drive line between the crankshaft and the camshaft resulting from various torque influences on the camshaft can be reduced, whereby the gear or chain wheel in the driveline can be reduced. It is possible to reduce wear or the noise resulting therefrom. The vibration damper comprises a circular disk having a plurality of cylindrical holes arranged so that its longitudinal axis is parallel to the rotation axis of the driving wheel and is symmetrically distributed around the driving wheel. Also have a small diameter cylindrical pendulum weight. The weight is free to move within the bore, and in operation, the weight is affected by centrifugal forces tending to push the weight toward a position closest to the outer circumference of the drive wheels. As the rotational speed increases, the centrifugal force increases and the weight can move within the hole with a natural period that is directly proportional to the rotational speed. As a result of the drive wheel oscillating in this cycle, the weight oscillates in the hole and thus has a direction opposite to the drive wheel oscillating direction, thus producing a torque that reduces that oscillation.

[0003] US Patent No. 4,848,183 describes a camshaft damper for damping torsional vibration in a camshaft, again in which the damper is integrated with the drive wheels, and The damper consists of a mass in the form of a ring fastened to the drive wheels by elements made of an elastomeric material. The combination of the inertia of this ring and the elasticity of the elastomer forms a pendulum system, so that during operation, the elastomer element absorbs the vibrations of the drive wheels, and this absorbed energy is converted into heat within the elastomer. Is converted.

US Pat. No. 5,040,500 describes a camshaft for controlling valves in an internal combustion engine, which camshaft has an additional cam disk, A cam disc can be formed on the drive wheel of the shaft, and this cam disc cooperates with a spring-loaded tappet roller, so that the cam disc is synchronized and of equal amplitude Also, in synchronization with the torque pulse applied to the camshaft when the valve opens and closes, the amplitude is equal and is affected by the varying torque directed in the opposite direction to the torque pulse. In other words, a vibration damper that attempts to completely exceed the exact total vibration component of the torque pulse obtained from the cam disk controlling the valve. To this end, a camshaft with three cam disks controlling the valve is provided with an additional cam disk having three cams, each of the three cams being associated with one of the cam disks controlling the valve. When each valve is actuated, it exceeds the torque pulse affecting the shaft.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a camshaft of the type described in the introduction, wherein the unexpected wear of the cam discs and tappet rollers is significantly reduced. It is.

[0006]

SUMMARY OF THE INVENTION In view of this, the present invention provides that at least one of the vibration damping regions on at least one cam disk comprising a vibration damper is greater than 16 ranks with respect to the rotation speed of the camshaft. One of several fluctuating torques
Or the total torque thereof can be influenced by the camshaft.

Surprisingly, a large crosshead type 2
The tappet roller, which drives the piston or valve driver of the fuel pump in the stroke internal combustion engine, dares to come out of contact with the cam disk and is subject to the effects of higher harmonic harmonics from the cam disk. Below, it has been proven that there is a risk of knocking back on the cam disc, which can cause notches on the cam disc and tappet roller. To date, this phenomenon has not been considered in the design of the camshaft system. The reason is that it was considered that the tappet roller would not come into non-contact with the cam disk at all because the force when the tappet roller was pressed against the disk was large. During continuous operation, such notches will cause the cam disks and tappet rollers to wear out unexpectedly prematurely. In particular, one or more harmonic oscillations significantly higher than the 16th order will cause such operational irregularities. This is surprising because, conventionally, when calculating the vibration of the shaft system of the internal combustion engine, only the vibrations up to the 16th rank are considered.

In the number and excursion states associated with a circular trajectory in which the damping of a particular higher order harmonic vibration, which is undesirable for any given camshaft, is achieved, this vibration damping region is above the cam disc. Can be arranged.

In addition, a cam disk having a spring-loaded tappet roller is basically used.
It is one advantage of the vibration damper according to the invention that it is a simple, robust and fully proven mechanism, so that stable operation of the vibration damper is ensured.

This vibration damping cam disk is disposed on the cam shaft at a position away from the driving wheels. In large engines, the drive wheels have a very large mass with respect to the camshaft, so they form a node in the camshaft vibration, and Best damping is achieved by locating the vibration damping disk at a remote location, for example, at or near the antinode in the vibration of the camshaft.

[0011] In one embodiment of the present invention, 16
To generate each of the higher order torques, the cam disk of the vibration damper has at least one of its outer perimeters having peaks located at mutual rotational angular positions equal to 360 ° divided by the respective torque order. In part, it comprises at least one cam disk having a vibration damping area. In this way, the vibration damping region can be constituted by a continuous uniform trajectory in which one peak and one valley alternate along the outer periphery of the cam disk, so that it is simple and therefore relatively simple. It is possible to manufacture a vibration damping cam disk at low cost. In this embodiment, it is further possible for the disks, which attenuate harmonic vibrations of different orders, to be mutually phase adjustable for the purpose of optimizing the vibration damping. This is particularly advantageous when running in a new engine design.

In another embodiment of the present invention, in order to generate a total value of several torques of 16 or more ranks, the cam disk of the vibration damper is provided with a plurality of orbits in the orbit. At least one cam disk having peaks and valleys formed over a portion of its outer circumference, each of which has a mutual rotation equal to 360 ° divided by the respective torque rank. It is arranged at an angular position. When it is required to damp several orders of harmonics, it is an advantage that several orders can be attenuated on the same disk without the need for one disk for each order. It is.

In one preferred embodiment, the cam disc of the vibration damper is adapted to exclusively dampen at least one separate cam disc, ie one or more orders of harmonic vibration, and comprises a fuel pump or It has a cam disk that does not act simultaneously to drive the valve. It becomes much easier to design the vibration damping areas in separate cam discs so that conventional cam discs can be designed uniformly as standard equipment. Adjustment of the separate cam discs to one another does not affect the order of operation of the fuel pumps or valves. In addition, a separate location near the antinode of the camshaft, where the most efficient damping is obtained, which would be obtained if the vibration damping disc were integrated with the normal cam disc of the engine, was obtained. It is an advantage that the cam disks can be arranged in close proximity.

Furthermore, in this embodiment, typically the torque required to damp unwanted harmonics of higher order than, for example, the torque required to drive the fuel pump is significantly smaller. The vibration damping cam disc with the associated tappet roller can be of a significantly lighter structural design than a cam disc with a tappet roller driving a fuel pump or valve drive. For example, the torque required to attenuate undesirable higher order harmonic vibrations is, for example, 1,000 N
m, the maximum torque required to operate the fuel pump may be about 70,000 Nm. Therefore, a relatively small spring force is required to press the tappet roller against the vibration damping cam disk. This means that the wear rate of the components is slow, and a trouble-free and long-life operation is ensured. Finally, significant savings are realized by reducing the required mass of the disc, since cam discs with an associated tappet roller constitute an expensive machine component.

In certain large engines, the drive wheels are located between the ends of the camshaft for various structural reasons, where the cam disk of the vibration damper is located at one end of the camshaft or at one end of the camshaft. At least one separate cam disc may be provided at or near the ends. As described above, in a large engine, the driving wheels form one node on the camshaft, so that the driving wheels are disposed between both ends of the camshaft, so that antinodes are formed at both ends of the shaft. Formed so that the vibration-attenuating cam disk can be conveniently located at that location.

On the other hand, if the driving wheels are arranged at positions adjacent to both ends of the camshaft or one end thereof, the cam disks of the vibration damper are arranged at the other ends of the two ends of the camshaft or at positions near the other end. At least one separate cam disc can be provided, the end of which will have an antinode.

In still another embodiment of the present invention, the cam disk of the vibration damper comprises a cam disk for driving a fuel pump, wherein the vibration damping region is
It is arranged at a position substantially outside the outer peripheral portion of the cam disk that operates the fuel injection itself. In this way, the vibration damper can be integrated into the normal cam disk of the engine, eliminating the need for a separate cam disk, and the vibration damping area does not adversely affect the operating sequence of the fuel pump. The working parts in the cam disk that control the fuel pumps associated with the different cylinders in the engine are distributed approximately uniformly over the rotational trajectory of the camshaft, so that there are several vibration damping areas for the same undesirable vibration mode. It is arranged on such a cam disc, so that the whole rotation track can be covered with vibration damping peaks and valleys.

In one modification of the above-described embodiment of the present invention, the cam disk of the vibration damper includes a cam disk for driving an exhaust valve. It is disposed at a position substantially outside the outer peripheral portion of the cam disk to be operated.

[0019] The cam disk of the vibration damper may further comprise a cam disk having a vibration damping region adapted to overcompensate for one or more undesirable vibration modes. This means that, as described above, if it is not efficient to arrange the vibration damping area along the entire circumference of the cam disk in consideration of the operation order of the fuel pump and the valve, the vibration damping cam disk may be mounted on the engine. This is particularly advantageous when it is desired to integrate it into a conventional cam disc. For this reason, overcompensation for the undesired vibration modes takes place outside the working part of the cam disc, while the working part of the cam disc passes through the tappet roller, where no compensation is made. In addition, accumulation of undesirable vibration energy components can be avoided. Therefore, an appropriate average damping can be achieved during one revolution of the cam disk.
In this way, it is possible to integrate sufficient vibration damping of the undesired vibration modes into a single disk of the normal cam disk of the engine.

It is sufficient to partially compensate for the order of the undesired harmonic oscillations and to avoid the adverse effects caused by these oscillations, so that there is sufficient damping so that it is not necessary to completely eliminate the undesired oscillations. Oftentimes.

[0021]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings as an example of the present invention.

FIG. 1 shows a camshaft 1 of a 10-cylinder, 2-stroke diesel engine. The camshaft 1
Comprises a number of parts 2, 3, 4, 5, 6, 7 interconnected at their extensions by a rigid coupling 8. The drive wheel 9 of the camshaft is arranged on the part 5 and is driven in synchronization with the camshaft of the engine by a chain drive or a gear transmission, not shown. Each of the other parts 2, 3, 4, 6, 7 is associated with two adjacent cylinders in the engine, for each cylinder supporting a cam disk 10 for operating the fuel pump, and The cam disk 11 for operating the exhaust valve is supported. For simplicity, all cam disks 10, 11 in FIG. 1 are shown at their maximum diameter. The illustrated camshaft 1 is adapted for a 10-cylinder engine, whose camshaft has a weight of 2 due to its weight.
And the transmission between the crankshaft and the camshaft 1 is arranged in the divided part. Also,
The camshaft 1 can also be manufactured as a single piece, which has no effect on the possibility of application of the invention. Further alternatively, the transmission between the crankshaft and the camshaft 1 may be arranged at the end of the crankshaft.

The driving wheel 9 has a large diameter with respect to the other parts of the camshaft 1 and a large mass with respect to the other parts of the camshaft 1, so that the driving wheels 9 have a large diameter. Has a large moment of inertia with respect to the other parts of the camshaft 1 so as to form one node for the torsional vibration of the camshaft.

FIG. 2 shows a perspective view of one of the intermediate parts 3, 4, 6 of the camshaft shown in FIG. On the left half of the shaft,
A first set of cam discs 10, 11 consisting of two spaced discs is interference fitted. The left disk 10 serves to activate the fuel pump for the first cylinder, and the right disk 11 serves to activate the exhaust valve of the same cylinder. In the right half of the shaft part, a second set of cam disks 10, 11 corresponding to the first set is arranged for a second cylinder. The camshaft 1 is arranged on two cam disks,
Each set of cam discs 10,
11 is supported.

FIG. 3 shows a cam disk 10 arranged on the cam shaft 1 and in a roller guide housing 15, which is provided with an associated tappet roller 16. The tappet roller is spring-loaded so as to be able to contact the cam disk 10 and is connected to a fuel pump (not shown). The tappet roller rolls around the cam disk 10 during operation of the engine. The outer circumference of the cam disc has an operating part consisting of two different areas 17, 18 in which the distance to the axis of rotation 19 of the camshaft is increased on one side and shortened on the other. One of these regions 17 activates the fuel pump when the engine operates in its normal direction of rotation, indicated by arrow 20, and the other region 18 activates the pump after reversing its direction of rotation. Work. As the working part passes through the tappet roller 16, the tappet roller is pressed upwards, thereby activating the fuel pump. The cam discs 10 associated with the different cylinders are arranged on the camshaft 1 with their injection actuating parts rotating about the axis 1 with respect to each other, so that the injection is matched to the ignition process of the engine. Can be. The cam disk 11 for the operation of the exhaust valve functions according to corresponding and well-known principles.

FIGS. 4 and 5 show a separate cam disk 21 adapted to attenuate torsional vibrations in the camshaft 1. The cam disk 21 functions to exclusively attenuate vibration. Therefore, for example, it is not necessary to change the position of the camshaft 1 of the normal cam disks 10 and 11 as a matter of course. The cam disk 21
Can be arranged. The separate cam disc 21
It can be arranged on a separate camshaft portion not shown.
The camshaft part can be connected to the other part of the camshaft 1 or, together with the camshaft's cam discs 10, 11, can be fitted directly into one of the parts.

As in the case of the ordinary cam disks 10 and 11,
This separate cam disc 21 has an associated tappet roller 22. The tappet roller is loaded by a spring 23 so as to be able to abut against the cam disk 21 and rolls on the cam disk during operation of the engine. The axis of the tappet roller 22 is
The slider is rotatably suspended in a state parallel to the camshaft 1, and the slider is guided in the roller guide housing 25 at right angles to the camshaft 1. The outer circumference of the separate cam disk 21 is substantially circular, and has a peak 26 and a valley 27.
A large number of vibration damping regions in the form of are formed. When the cam disc 21 is rotating, the spring-loaded tappet roller tends to follow the peaks 26 and valleys 27. As a result, the cam disc is subject to time varying torque according to the distribution of peaks and valleys along the circumference of the cam disc. Peak 26 and valley 2
7, the torque of the vibration-attenuating cam disk 21 relative to the camshaft 1 is such that the undesired vibration-generating torque in the camshaft 1 cancels out, thereby damping or eliminating the undesired vibration-generating torque. The phase has been adjusted.

The separate cam disc 21 may be capable of damping one or more orders of undesirably large harmonics. FIG. 4 shows an example of the design of the outer circumference of the separate cam disk 21 for damping the 38th-order undesired harmonic vibrations. Along this circumference,
38 uniform vibration damping regions are formed, each of which consists of a peak 26 and a valley 27, in which case these peaks are arranged at the same mutual rotational angle position. . The radial difference between the peaks 26 and the valleys 27 can be relatively small with respect to the diameter of the cam disc 21. The difference can be, for example, 6 mm and the diameter can be 1 m. During operation of the engine, the tappet roller 22 affects the separate cam disc 21 with increasing and decreasing torque 38 times per revolution of the camshaft 1, and thus 38
Damping the harmonic torsional vibration of the rank.

If several different orders of harmonic vibration are not desired, a cam disc 21 which is separate from each other and which can be damped in that order can be used. Alternatively, a single separate cam disc 21 which can dampen some of these undesirable orders
May be used. Such a cam disc 21 which damps some orders of vibration may have an outer periphery with a waveform pattern, not shown, consisting of peaks and valleys,
In this case, this waveform pattern is formed by superimposing different waveform patterns, each of which is disposed on a respective cam disk 21;
Each order of harmonic vibration can be attenuated.

FIGS. 6 and 7 show that the cylinder diameter is 90c.
The effect of the present invention on an example of a 10 cylinder, 2 stroke diesel engine manufactured by MAN B & W is shown in the model of 10L90MC, '90', denoting m. In this engine, the drive wheels 9 are
Is disposed at a position above the camshaft 1 shown in FIG. In the illustrated diagram, the abscissa indicates the rotational speed of the engine in units of revolutions per minute, and the ordinate indicates the torsional vibration of the camshaft 1 in units of milliradians per minute. Furthermore, the vertical line MC
R indicates the highest continuous rated speed of the engine.
In general, large diesel engines must be able to operate slightly slower than this speed and continuously at this speed for an extended period of time, so during most of their operating time this particular operating range It is important that undesirably large torsional vibrations do not occur in the camshaft 1 within.

In the diagram of FIG. 6, the graph shows the accumulated torsional vibration in camshaft 1 when vibration damping according to the invention is not used. The graph clearly shows that there is a significant peak 28 between approximately 79 and 84 rpm, which is within the normal operating range, which is highly undesirable. Such accumulated torsional vibrations are decomposed into a number of harmonic vibrations of various orders by a known method by Fourier analysis, and the total value of these harmonic vibrations forms the vibration mode shown in graph a. A number of graphs c below graph a show the main vibrations of these harmonic vibrations, each of which shows a particular order of the harmonic vibrations as displayed in the graph. Undesirable peak 2 in graph a
It is clearly seen that the harmonics of Nos. 38 and 39 contribute to No. 8.

In the graph of FIG. 7, the graph b is
When the harmonic vibrations of the 38th and 39th ranks are attenuated by one or more cam disks according to the present invention, the torsional vibrations accumulated in the camshaft 1 are shown. In fact, the graphs of these two harmonics have been omitted in the diagram, and in fact the graph b, which constitutes the sum of the remaining harmonics, does not have the particular large peak 28 shown in FIG. . in this way,
Undesired vibration modes are significantly attenuated.

Undesired harmonic vibrations of the 38th and 39th ranks can be attenuated by one or more cam disks 21 having the outer circumference shown in FIG. Has 38 peaks 26 in combination with one or more corresponding cam disks with. In one simple embodiment of the present invention, with a camshaft 1 shown in FIG. 1 and adapted to be mounted on a model 10L90MC engine as described above, 38
A cam disk 21 having 39 peaks and a cam disk 21 having 39 peaks can be arranged at one end of the shaft 1. In another embodiment of the invention, the drive wheel 9 can be arranged at one end of the shaft 1 and a separate cam disk 21 can be arranged at the other end of the cam shaft.

During the running-in operation of the prototype of the camshaft 1, 2
The mutual phase displacement between the two different cam discs 21 can be optimized to obtain the best possible damping, and the 38 and 39 with a predetermined phase displacement.
A single cam disk adapted to dampen the highest order vibration can be formed for future use. In yet another embodiment of the present invention, a separate cam disk (not shown) is provided at one end of the camshaft 1 shown in FIG. 1 to dampen both 38th and 39th harmonics. Or it is arranged at the other end. Different numbers of cam disks and other positions of the disks can be employed depending on the conditions of the undesired vibration amplitude and space.

The embodiment described above, in which the undesirably large harmonic vibrations of the camshaft 1 are in particular of the 38th and 39th ranks, has a specific firing sequence and also the normal Is applied to the engine type 10L90MC having the angular positions of the cam disks 10 and 11 described above. In a different firing order, or cam disk 10,
11 are slightly different, the cam disc 1
Due to the high contact forces between 0, 11 and the tappet rollers, very different modes of vibration occur in the camshaft 1 of this engine, so that undesirably large harmonic vibrations are of other order. According to the present invention, such unwanted harmonic vibrations can be damped by a cam disc adapted to dampen these particular order vibrations in the manner described above. In addition, for other relatively large engine types, such as the MAN B & W 8L60MC having eight cylinders and a cylinder diameter of 60 cm, undesirable harmonic vibrations other than those listed above may occur.

In order to be able to dampen the amplitude of the undesired vibrations, the width of the vibration damping area of the separate cam disc 21, the dimensions and mass of the cam disc 21 and the tappet roller 22 and the tappet roller 22 It is possible to change parameters such as the spring constant and the preload of the spring 23 that presses against the spring. The phase shift between the vibration damping torque and the torque that causes the undesired vibrations can be achieved by rotating the vibration damping cam disc 21 relative to the camshaft 1 or by rotating the tappet roller 22 to optimize the damping effect. Can be adjusted by displacing in the circumferential direction.

The different embodiments of the vibration damping cam disk described above and their positions on the camshaft 1 can be combined. For example, a separate damping of one order of unwanted harmonic vibration in combination with a region of damping another order of unwanted harmonic vibration located on one or more cam disks 10 driving the fuel pump. Can be used. Also, for example, a separate cam disc 21 that attenuates one order of unwanted harmonic vibration may be located at one end of the camshaft, and at the same time, a cam may be provided to attenuate another order of unwanted harmonic vibration. It is also possible to place a separate cam disc near the antinode at a position remote from the shaft ends 13, 14 and between its normal cam discs 10, 11.

[Brief description of the drawings]

FIG. 1 is a side view of a cam shaft.

FIG. 2 is a sectional perspective view of the camshaft of FIG.

FIG. 3 is a view of a cam disc with an associated tappet roller for activating fuel injection, as viewed in the direction of the cam shaft.

FIG. 4 is a schematic view of a separate cam disk with an associated spring-loaded tappet roller for vibration damping according to the invention, as viewed in the direction of the camshaft.

FIG. 5 when viewed in a direction perpendicular to the camshaft;
FIG. 4 is a schematic view of a separate cam disk similar to FIG.

FIG. 6 is a diagram illustrating an example of torsional vibration of the camshaft when there is no damping, plotted against the rotation speed of the engine.

FIG. 7 is a view corresponding to FIG. 6, in which undesirable higher-order harmonic vibrations are attenuated according to the present invention;

[Explanation of symbols]

1 Camshaft 2, 3, 4, 5,
6, 7 part 8 Coupling 9 Drive shaft of camshaft 10, 11 Cam disc 13, 14 End of cam shaft 15 Roller guide housing 16 Tappet roller 17, 18, Area 19 Rotation axis of cam shaft 21 Cam disc 22 Tappet roller 23 Spring 24 Slider 25 Roller Guide Housing 26, 28 Peak 27 Valley

 ──────────────────────────────────────────────────の Continuation of front page (71) Applicant 594140904 Center Syd, 161 Stamholmen, DK-2650 HVIDOVR E, Denmark

Claims (9)

[Claims] 1. A large cross-head type two-stroke internal combustion engine, comprising: a drive wheel (9) driven synchronously with a crankshaft of the engine via a gear or a chain drive; and a piston of a fuel pump. Or several cam disks (10, 11) having associated tappet rollers (16, 22) for driving the valve drive in a reciprocating motion and an associated cam disk (10, 11) arranged at a location remote from the drive wheels (9). A vibration damper comprising at least one cam disk (10, 11, 21) having a spring-loaded tappet roller (16, 22), wherein at least one cam disk (10, 11, 21) of said vibration damper is provided. , Related tappet rollers (1
6, 22), and a vibration damping region displaced from a circular track, wherein the force from at least one spring-loaded tappet roller (16, 22) is applied to the camshaft with varying torque. At least one cam disc (1) comprising a vibration damper is provided on the camshaft (1) of the internal combustion engine, which affects (1).
Some of the vibration damping regions at 0,11,21) comprise several varying single torques or a sum of torques of order 16 or more relative to the rotational speed of the camshaft (1). A camshaft characterized in that it can influence the camshaft (1). 2. The camshaft (1) according to claim 1, wherein the cam disks (10, 11, 21) of the vibration damper include at least one cam disk to generate each of the torques of 16 or more ranks. The at least one cam disk has a vibration damping region over at least a portion of its outer circumference having peaks located at mutual rotation angles equal to 360 ° divided by the respective torque rank. A camshaft. 3. The camshaft (1) according to claim 1, wherein the cam disc (10, 1) of the vibration damper generates a total value of several torques of 16 or more ranks.
1, 21) includes at least one cam disk in which a peak and a valley are formed over at least a part of its outer periphery in one orbit constituting a superposed portion of several orbits. A camshaft characterized in that each of said tracks has peaks located at mutual rotation angles equal to 360 ° divided by the respective torque rank. 4. A cam shaft (1) according to claim 1, wherein the cam disk (10, 1) of the vibration damper is provided.
, 21) is provided with at least one separate cam disk (2
A camshaft characterized by comprising (1). 5. The camshaft (1) according to claim 1, wherein the drive wheel (9) is connected to an end (13,
14) and the cam disk (1) of the vibration damper.
0, 11, 21) is at one or both ends (13, 1) of the camshaft.
At least one position 4) or a position close to the end thereof.
A camshaft characterized in that it comprises two separate cam disks (21). 6. The camshaft (1) according to claim 1, wherein the drive wheel (9) is arranged at one of the ends of the camshaft or at a position close to the one end. The cam disk (10, 11, 21) of the vibration damper has at least one separate cam disk (21) located at or near the other end of the cam shaft end (13, 14). ). 7. A cam shaft (1) according to claim 1, wherein the cam disk (10, 1) of the vibration damper is provided.
1, 21) is a cam disk (1) for driving a fuel pump.
0), wherein the vibration damping region is arranged at a position substantially outside the outer peripheral portion (17, 18) of the cam disk for operating the fuel injection itself. 8. The camshaft (1) according to claim 1, wherein a cam disk (1) of the vibration damper is provided.
0, 11, 21) drive the exhaust valve by the cam disk (1).
1) The camshaft according to 1), wherein the vibration damping region is arranged at a position substantially outside the outer peripheral portion of the cam disk that operates the opening and closing sequence of the valve. 9. A cam shaft (1) according to claim 1, wherein the cam disk (10, 1) of the vibration damper is provided.
1, 21), wherein the camshaft comprises a cam disc, the cam disc having a vibration damping region adapted to overcompensate one or more vibration modes that are undesirably large.