CN107208503B

CN107208503B - Adjusting device for adjusting valve timing of internal combustion engine

Info

Publication number: CN107208503B
Application number: CN201680007099.5A
Authority: CN
Inventors: 斯文·多瑞; 克劳迪娅·杰林斯基; 安德里亚斯·格雷奇; 约阿希姆·塞茨
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2015-01-26
Filing date: 2016-01-14
Publication date: 2020-04-14
Anticipated expiration: 2036-01-14
Also published as: CN107208503A; WO2016119783A1; DE102015201254A1

Abstract

The invention relates to an adjusting device (1) for adjusting the valve timing of an internal combustion engine, comprising a drive wheel (2) and a driven section (3) that is fixed to a camshaft, wherein the drive wheel (2) is rotatably connected to the driven section (3) by means of a centrifugal force actuating device (4) in such a way that the driven section (3) can be rotated relative to the drive wheel (2) between an advanced position and a retarded position within a range of rotational angles depending on the rotational speed of the drive wheel (2).

Description

Adjusting device for adjusting valve timing of internal combustion engine

Technical Field

The invention relates to an adjusting device for adjusting the valve timing of an internal combustion engine (for example a gasoline or diesel engine) of a motor vehicle, preferably a motorcycle or a scooter, having a drive wheel which is connected or can be connected in a rotationally fixed manner directly or indirectly to an output shaft of the internal combustion engine, and having a driven section which is fixed or can be fixedly mounted on a camshaft.

Background

Such adjusting devices, which are fitted on the end of a camshaft of an internal combustion engine, for example in the form of hydraulic camshaft adjusting devices according to the construction of a vane unit, are known in principle from the prior art. Such a camshaft adjusting device is disclosed, for example, in DE 10253496 a 1.

The known hydraulic camshaft adjusting devices are particularly suitable for use in automotive applications due to the hydraulic control and their relatively complex design, but are not very suitable for low-cost internal combustion engines, in particular in the context of small-engine motor vehicles (e.g., two-wheeled vehicles such as motorcycles or scooters), since the hydraulic performance is significantly lower in these small vehicles or the engine electronics are significantly limited compared to private vehicles or heavy goods vehicles. In particular, the expensive shift actuators using such camshaft adjusting devices may render the internal combustion engine, as is well known in the automotive field, less suitable for use in a two-wheeled motorcycle.

Furthermore, mechanical camshaft adjusters are known, but these have relatively complex mechanical/mechanical components comprising a relatively large number of components.

Disclosure of Invention

The object of the present invention is therefore to provide an adjusting device for a camshaft, which adjusting device should on the one hand have as few components as possible and be produced inexpensively, and on the other hand should have as low as possible the power consumed by the internal combustion engine when the adjusting device is operated during operation.

The object is achieved by the feature that the drive wheel is connected to the output section in a rotatable manner by the centrifugal force actuating device in such a way that the output section can be rotated in operation relative to the drive wheel to an advanced position or a retarded position within a (first) rotational angle range as a function of the rotational speed of the drive wheel.

The centrifugal force actuating device has a plurality of centrifugal parts, preferably two, particularly preferably more than two, wherein the center of mass/center of mass of each centrifugal part is arranged eccentrically to the drive wheel and/or the driven section (i.e. eccentrically to the axis of rotation of the drive wheel and/or the driven section). This makes the construction of the centrifugal force actuating device particularly simple.

In addition, the centrifugal element is pivotably/rotatably mounted in the first receiving region in a first mounting position on the drive wheel. In this case, the at least one centrifugal element is preferably rotatable about the first bearing position within a certain (second) rotational angle range. In this way, a particularly stable mounting of the centrifugal element relative to the drive wheel is achieved.

Furthermore, the centrifugal part is connected to the driven section in the second receiving region by a form-fitting connection. In this case, the positive-locking connection is designed such that the respective eccentric is guided such that it can be displaced in the radial direction relative to the driven section. This makes the construction of the adjusting device particularly simple.

The centrifugal element is supported at a support point formed on the drive wheel by means of a movement pin or a connecting pin (also referred to as a support pin) which is fixedly connected to the drive wheel. Furthermore, each eccentric is guided displaceably in a form-fitting manner in a radially extending groove in the output section by a movement pin. In this way, it is only necessary to provide a groove in the output section, preferably on the end face of the output section, in order to establish an effective connection of the output section to the at least one centrifugal element. The centrifugal element is therefore connected in the second receiving region by a positive-locking connection to the driven section according to the invention and is each guided in the driven section in a positive-locking manner movably by a movement pin (which is guided in a positive-locking manner movably in a groove extending radially in the driven section and designed as an elongated groove). This results in a particularly inexpensive support.

According to the invention, a centrifugal force actuated, discontinuous two-vane adjusting device is realized, which is mainly used in single cylinder engines or single cylinder internal combustion engines of motorcycles. In particular, a cost-effective internal combustion engine can be produced in which a reliable phase adjustment between the output shaft of the internal combustion engine and the camshaft is achieved.

Further advantageous embodiments are set forth in detail below.

Advantageously, the drive wheel and the driven section are arranged coaxially to each other. The construction of the adjusting device is thereby further simplified.

Furthermore, the output section directly forms the end region of the camshaft, i.e. is integrally connected to the camshaft, which further simplifies the design of the adjusting device.

A particularly simple switching between the advanced position and the retarded position is achieved if the bearing position and the movement pin are eccentric, i.e. arranged outside the center of mass of the at least one centrifugal element, so that the at least one centrifugal element is automatically moved outward by the centrifugal force/centrifugal force exerted thereon if a defined rotational speed threshold is exceeded.

In this respect, it is advantageous if the centrifugal force operated device has two centrifugal parts, whereby the connection between the driving wheel and the driven section is more stable. If the centrifugal elements are preferably arranged uniformly distributed along the circumference of the drive wheel, a setting of the centrifugal force actuating device that is as balanced as possible is achieved.

It is also advantageous if the first centrifugal part is elastically prestressed with respect to the second centrifugal part, wherein the restoring spring preloads the centrifugal parts against one another with a certain preload force. In particular, the restoring spring is designed as a helical spring. In this way, a starting position of the centrifugal force actuating device is ensured in the rest position of the internal combustion engine.

A particularly compact design of the adjusting device is achieved if the driven section is inserted into the through-opening of the drive wheel via the axial end region. In this respect, it is particularly advantageous if the end sides/end faces of the driven section and the drive wheel are arranged flush with one another in the axial direction.

The adjusting device is reliably supported in the respective end position if the centrifugal force actuating device also has at least one brake unit which rotationally seals/fixes the drive wheel in the advance position and/or the retard position relative to the driven section.

According to a further embodiment of the invention, it is also advantageous if the connecting/bearing pin which forms the connecting/bearing pin for the eccentric is fixed in/connected with the driven section and the groove which receives the movement pin of the eccentric is instead arranged in the drive wheel. In this respect, it is also advantageous if at least one brake unit has an elastically prestressed detent body, wherein the detent body can engage in a recess in the drive wheel associated with an advance position or a retard position. A ball can be used in particular as the stop body. This makes the construction of the brake unit particularly simple.

Drawings

The invention is elucidated below on the basis of the accompanying drawings.

The attached drawings are as follows:

fig. 1 is an isometric view of an adjusting device according to an advantageous embodiment of the invention, wherein the driving wheel, the driven section and also the centrifugal force operating device can be clearly seen,

figure 2 is a side view of the adjustment device shown in figure 1,

fig. 3 is a front view of the adjusting device according to the invention of fig. 1 and 2, wherein the end sides of the drive wheel and of the driven section are clearly visible, and the rotatable support of the centrifugal element of the centrifugal force operating device is shown,

fig. 4 is a front view according to fig. 3, wherein in the illustration one of the two centrifugal parts of the centrifugal force operating device and the return spring pre-stressing the two centrifugal parts are omitted, so that the arrangement of the moving pin of the centrifugal part taken out in the groove of the driven section and the two grooves in the drive wheel belonging to the brake unit can be seen,

fig. 5 is a side view of a selected adjustment device similar to that of fig. 2, wherein, however, the adjustment device is arranged here to be rotated through a range of angles relative to fig. 2,

fig. 6 is a longitudinal section through the adjusting device according to the invention according to fig. 1, in which the section plane is parallel to and spaced from the axis of rotation of the adjusting device and extends through the bearing point of the centrifugal part and the brake unit, wherein the internal structure of the brake unit can also be observed,

fig. 7 is an isometric view of the adjusting device already shown in fig. 6 in the longitudinal direction, wherein the arrangement of the two centrepieces can be seen in a sectional plane,

fig. 8 is a perspective longitudinal section through an adjusting device according to the invention, wherein the adjusting device is here cut such that the section plane extends along the axis of rotation and simultaneously along the movement pins of two centrifugal parts (omitted here for clarity),

fig. 9 is a side view according to fig. 8, in longitudinal direction, cut through the adjustment device, wherein two centra-bles are used, and shown cut,

figure 10 is an isometric view of the adjustment device according to figure 9 cut in the longitudinal direction,

figure 11 is an isolated perspective view of a drive wheel as used in the adjustment device of the first embodiment,

figure 12 is a front view of the drive wheel shown in figure 11,

FIG. 13 is an isometric view of a driven section as used in the adjustment device of the first embodiment, an

Fig. 14 is a front view of the output section, wherein the end face of the output section, into which two grooves which receive the movement pins of the centrifugal force actuating device are inserted in a form-fitting manner during operation, can be seen in particular.

The drawings are only of a schematic nature and are only used for understanding the present invention. Like parts are marked with like reference numerals.

Detailed Description

The adjusting device according to the invention can be seen in its entirety in fig. 1. The adjusting device 1 is used for adjusting/setting the valve timing of a valve of an internal combustion engine. For the sake of clarity, the internal combustion engine is not shown here, but is preferably designed as a single-cylinder internal combustion engine. The internal combustion engine is an engine of a motorcycle.

The adjusting device 1 has a drive wheel 2. The drive wheel 2 is designed here as an externally toothed spur gear or cylindrical gear. The drive wheel 2 is used in a conventional manner for the rotationally fixed accommodation of endless traction means, i.e. a chain (alternatively also a belt), traction drive means (chain drive or belt drive), which are not further shown here for the sake of clarity. In the operating state of the internal combustion engine, the drive wheel 2 is therefore connected in a rotationally fixed manner to the output shaft/crankshaft of the adjusting device 1 via the traction means.

The adjusting device 1 has, in addition to the drive wheel 2, a driven section 3 which is fixed to the camshaft. The driven section 3 is in the present exemplary embodiment an integral component of the camshaft 18, i.e. a one-piece component of material. In a further embodiment, which is not shown here for the sake of clarity, it is also possible for the output section 3, which is fixed to the camshaft, to be separated from the camshaft 18 during the forming process and to be mounted together in a rotationally fixed manner with the camshaft 18 of the internal combustion engine only when the adjusting device 1 is assembled.

Due to the integrated design of the driven section 3 and the camshaft 18 selected in fig. 1, a plurality of cams 19 of the camshaft 18 for operating different intake or exhaust valves of the internal combustion engine are likewise integrated with the driven section 3.

The drive wheel 2 is rotationally connected to the output section 3 by the centrifugal force actuating device 4 in such a way that the output section 3 is rotated relative to the drive wheel 2 in a rotational angle range between an advanced position and a retarded position as a function of the rotational speed of the drive wheel 2. As can also be seen in fig. 1, the centrifugal force actuating device 4 has two

centrifugal parts

5a and 5b, which are identically shaped. The

centrifugal pieces

5a and 5b, which respectively form the centrifugal mass/centrifugal weight, are arranged distributed (offset by 180 ° and rotated by 180 °) along the circumference with respect to the rotational axis 17 (fig. 2) of the drive wheel 2/driven section 3. The first eccentric 5a is shaped like the second eccentric 5b and is received/fixed on the drive wheel 2 and the driven section 3 in the same way.

The first eccentric 5a is mounted on the drive wheel 2 at a first bearing location 6 a. The second eccentric 5b is mounted on the drive wheel 2 at a second bearing location 6b, which is arranged offset by 180 ° from the first bearing location 6a along a circular circumferential line. As can be seen particularly clearly in fig. 4, each

bearing point

6a, 6b is designed to be realized by a

bearing pin

20a, 20b, which bearing

20a, 20b accommodates/pivotably supports the

centrifugal piece

5a, 5b on the first accommodation region 21. Therefore, the first eccentric member 5a is rotatably/swingably supported on the drive wheel 2 about the first support pin 20 a. The second eccentric 5b is rotatably/pivotably mounted on the drive wheel 2 about a second bearing pin 20 b.

Each

bearing pin

20a, 20b extends in the axial direction of the rotational axis 17 away from the end side 11/end face of the drive wheel 11. The center of gravity of the first eccentric 5a, which is not shown in any more detail for the sake of clarity, is arranged offset in the circumferential direction and in the radial direction with respect to the axis of rotation of the first eccentric 5a formed by the bearing pin 20 a. The second eccentric 5b is likewise arranged offset in the circumferential direction and in the radial direction with respect to the axis of rotation of the second eccentric 5b, which axis of rotation is formed by the bearing pin 20 b.

The first housing area 21 of each centrifuge 5a is arranged in the rest position according to fig. 1 to 10. The rest position corresponds to an advanced position of camshaft 18. In another embodiment, the rest position corresponds to a hysteresis position. Viewed in the rest position, the radially inner movement pins 7a, 7b of the bearing

positions

6a, 6b are mounted/fixed on the second receiving areas 23 of the

centrifugal parts

5a, 5 b. Said first movement pin 7a extends parallel to the bearing pins 20a, 20b of the

respective centrepage

5a, 5 b. Since the first movement pin 7a extends parallel to the axis of rotation 17, the bearing pin 20 also extends parallel to said axis of rotation 17. The first movement pin 7a extends in the axial direction until it projects with a positive fit into the first groove 8a in the end face 12 of the output section 3. The second movement pin 7b likewise extends in the axial direction until it projects with a positive fit into the second groove 8b in the end face 12 of the output section 3.

As can be seen, for example, in fig. 4, 13 and 14, each

groove

8a, 8b is designed as an elongated groove extending in a radial direction along a radial line with respect to the axis of rotation 17. Thus, the first movement pin 7a is mounted so as to be movable in the radial direction relative to the driven section 3 within the first groove 8a, and the second movement pin 7a is mounted so as to be movable in the radial direction relative to the driven section 3 within the second groove 8 b. In fig. 4, the first movement pin 7a is arranged in a position inside the first groove 8a, which belongs to the advanced position/rest position of the output section 3.

If a predetermined rotational speed threshold (i.e. a first minimum rotational speed at which the drive wheel 2 and the driven section 3 are rotated) is exceeded, each of the

centrifugal pieces

5a or 5b is displaced outwards in the radial direction due to the centrifugal force/centrifugal force acting on its center of gravity (since the center of gravity of the

centrifugal piece

5a or 5b is set eccentrically to the rotational axis 17 of the drive wheel 2 of the driven section 3). In this case, the

centrifugal pieces

5a and 5b are rotated about the bearing

positions

6a and 6b on the drive wheel 2 over a predetermined second range of rotation angles to a pivoted position, which is distinguished from the rest position, in which the moving

7a or 7b is displaced/moved outwards in the radial direction simultaneously inside the two

grooves

8a and 8 b. In this case, the movement pins 7a and 7b are not only moved in a purely radial direction, but also moved by a certain amount in the circumferential direction of the axis of rotation 17 relative to the driven section 3, due to the rotation of the movement pins 7a and 7b about the

respective bearing locations

6a and 6 b. This causes a relative rotation between the drive wheel 2 and the driven section 3 in a first angular range of rotation, which is associated with a second angular range of rotation. In the hysteresis position achieved thereby, the output section 3 is arranged rotationally with respect to the drive wheel 2 over a rotational angle range. In the pivoted position, each eccentric 5a, 5b rests against a stop pin 24 which is fixedly connected to the drive wheel 2. In a further embodiment, in which the lagging position belongs to the rest position, the pivoted position belongs to the advanced position.

As can also be clearly seen in fig. 1, the two

movement pins

7a and 7b of the two

eccentric members

5a and 5b are elastically prestressed against one another by means of a return spring 16 designed as a helical spring. The restoring spring 16 is designed as a tension spring, and therefore presses the

centrifugal parts

5a and 5b against one another during operation with respect to their movement pins 7a and 7b by means of a certain elastic biasing force. Thus, in addition to the inertia of the

centrifugal pieces

5a and 5b, the spring force of the return spring 16 and the pre-pressure spring 22 of the brake unit 13 can determine the minimum rotational speed at which the

centrifugal piece

5a or 5b is automatically switched from the rest position/advanced position into the swing position/retarded position.

It can also be seen in fig. 9 that the driven section 3 and thus the camshaft 18 are moved into the central passage opening 10 in the form of a circular through-opening/through-bore by means of the axial end region 9 of the driven section 3. In addition, it can be seen here that the end side 11 of the drive wheel 2 is flush with the end side 12 of the driven section 3 on the side of the

centrifugal pieces

5a, 5 b.

As further shown in fig. 6 and 7, a brake unit 13 is also associated with each

centrifugal part

5a and 5b, wherein for the sake of clarity only the brake unit 13 of the second centrifugal part 5b is shown here, but the first brake unit 13 of the first centrifugal part 5a has the same structure and function. The brake unit 13 has a pretensioned spring 22 and a detent body 14 in the form of a ball. The pretensioning spring 22 bears with its end against the stop body 14 and with its second end opposite the first end is mounted in the second centrifugal part 5b in a receiving bore designed as a blind bore. In the advanced and retarded positions, the stop body 14 is jammed in the recess 15 of the drive wheel 2, so that in the advanced and retarded positions a certain minimum adjustment force must be applied in order to enable the

centrifugal piece

5a or 5b to move again out of the advanced or retarded position. In fig. 6, the stop body 14 snaps into a groove 15 having the shape of a ball section belonging to the advanced position.

For the sake of completeness, it should also be mentioned that, for reasons of clarity of illustration, further embodiments which are not illustrated here are considered, it also being possible for the grooves 8a/8b of the camshaft 18/driven section 3 and the pin connections (connecting the bearing pins 20a, 20b) illustrated in the construction to be replaced as well. Thus, in a further embodiment, the connecting/

bearing pins

20a, 20b, which constitute the bearing

locations

6a, 6b for one of the

centrifugal pieces

5a, 5b, are fixed in/connected with the driven section 3, and instead the

grooves

8a, 8b, which accommodate the movement pins 7a, 7b of the

centrifugal pieces

5a, 5b, are arranged in the drive wheel 2.

Moreover, in other embodiments, more than 2

centrifugal pieces

5a, 5b are provided even in the centrifugal force operated device 4.

In other words, the invention thus comprises a centrifugally controlled two-point camshaft adjusting device (drive wheel 2 with centrifugal force actuating device 4) which reduces the high valve clash mainly at engine start-up and at low engine speeds of the internal combustion engine. This concept is based on the following working principle: the centrifugal weights (

centrifugal parts

5a and 5b) during operation form a rotation between the camshaft 18 and the sprocket wheel or drive wheel 2. As the engine speed increases and after exceeding the gear change speed, the movement of the

centrifugal weights

5a and 5b rotates the position of the camshaft 18 relative to the driving wheel 2. The centrifugal weights then move in an outward radial direction to an end stop (stop pin 24). The end stop 24 is located in the drive wheel 2. In this case, the transmission of the chain rotation is always carried out by the sprocket or drive wheel 2 via the connecting pins (bearing

pins

20a, 20b) to the

centrifugal weights

5a and 5b and also via the moving

pins

7a, 7b and the

slots

8a, 8b to the camshaft 18. By changing the position of the

centrifugal weights

5a, 5b, a rotation between the drive wheel 2 and the camshaft 18 is produced by means of the movement pins 7a, 7b in the

grooves

8a, 8 b. This rotation is finally expressed as the adjustment angle between the drive wheel 2 and the camshaft 18. The adjusting device 1 is thereby switched from the basic position (rest position) to the maximum adjusting position (pivot position) as a function of the rotational speed. Braking in the final position can be realized by means of a further braking device (brake unit 13) (ball spring unit) is conceivable.

The camshaft 18 and the drive wheel 2 should be as flush as possible with each other in the axial direction, wherein the drive wheel 2 provides accommodation for two linking

pins

20a, 20 b. There should be two or more

centrifugal weights

5a, 5b arranged symmetrically to the axis of rotation 17 and fixedly connected to the drive wheel 2 by means of respective connecting

pins

20a, 20 b. The

centrifugal weights

5a, 5b are connected to the camshaft 18 by means of respective movement pins 7a, 7b, which are embedded in the

centrifugal weights

5a, 5b and are connected tangentially to the camshaft 18 by means of

grooves

8a, 8b in a form-fitting manner. In this case, the greatest centrifugal force effect is achieved by the pin position (connecting the drive wheel 2/

centrifugal weights

5a, 5b) being arranged as far outwards as possible. The maximum outward movement of the

centrifugal weights

5a, 5b is limited by an end stop 24 additionally fitted in the drive wheel 2. The restoring spring 16 suspended in the middle of the camshaft 18 predetermines the basic position of the double wing (camshaft adjusting device). Alternatively, the restoring spring 16 can also be designed as a torsion spring (made of leaf spring material) which is preferably connected directly to the

centrifugal weights

5a, 5 b.

Both of the described adjustment angles (i.e. adjustment positions) can be ensured by means of respective final position stops, which are realized by means of the brake unit 13, in order to counteract the acting camshaft shifting torque. The braking unit 13 is formed by a blind hole with a pretensioning spring 22 and a stop body 14 in the form of a ball, which is integrated in the

centrifugal weights

5a, 5b, and by two recesses 15 in the drive wheel 2. The stop bodies 14 engage in corresponding hemispherical recesses 15 (two adjustment positions: a preferred position at low engine speeds (rest position) and a maximum adjustment position at high engine speeds (pivot position)). The brake unit 13 serves to ensure the desired final position (of the drive wheel 2 relative to the camshaft 18), so that a better acquisition of the camshaft transformation torque is possible. Since the camshaft change moment is accompanied by a higher increase in the engine speed, the inertia of the

centrifugal weights

5a and 5b should be able to prevent an undesired disengagement of the brake unit 13.

List of reference numerals

1 adjusting device

2 driving wheel

3 driven section

4 centrifugal force operating device

5a first eccentric

5b second eccentric

6a first supporting position

6b second support position

7a first kinematic pin

7b second kinematic pin

8a first groove

8b second groove

9 axial end region of the driven section

10 through hole

11 end side of driving wheel

12 end side of driven section

13 brake unit

14 stop body

15 groove

16 return spring

17 axis of rotation

18 camshaft

19 cam

20a first support pin

20b second bearing pin

21 first accommodation area

22 pre-tightening spring

23 second accommodation area

24 stop pin

Claims

1. An adjusting device (1) for adjusting the valve timing of an internal combustion engine, having a drive wheel (2) and a driven section (3) which is fixed to a camshaft, wherein the drive wheel (2) is rotatably connected to the driven section (3) by means of a centrifugal force actuating device (4) in such a way that the driven section (3) can be rotated to an advanced position or a retarded position relative to the drive wheel (2) in the operating mode within a range of rotational angles as a function of the rotational speed of the drive wheel (2), wherein the centrifugal force actuating device (4) has a plurality of centrifugal parts (5a, 5b) whose center of mass is arranged eccentrically to a rotational axis (17) of the drive wheel (2) and/or of the driven section (3), wherein the centrifugal parts (5a, 5b) are mounted in a first receiving region (21) in a pivotable manner at a mounting position (6a, 6b) on the drive wheel (2), 6b) Characterized in that the centrifugal parts (5a, 5b) are connected in a second receiving region (23) to the driven section (3) by a form-fitting connection and are each guided in a form-fitting manner in the driven section (3) so as to be movable by means of a movement pin (7a, 7b) which is mounted in a form-fitting manner in a radially extending groove (8a, 8b) in the driven section (3) and which is designed as a long groove, the end sides of the driven section (3) and of the drive wheel (2) being arranged flush with one another, and one end of the movement pin (7a, 7b) being connected by means of a return spring (16).

2. The adjusting apparatus (1) as claimed in claim 1, characterized in that the driven section (3) is inserted into a through-opening (10) of the drive wheel (2) via an axial end region (9).

3. The adjusting apparatus (1) according to one of claims 1 or 2, characterized in that the centrifugal force operating apparatus (4) has at least one brake unit (13) which stops the drive wheel (2) relative to the driven section (3) in an advance position and/or a retard position.

4. Adjusting device (1) according to claim 3, characterized in that the at least one brake unit (13) has an elastically prestressed detent body (14) which can be latched in a recess (15) in the drive wheel (2) assigned to an advance position or a retard position.

5. The adjustment device (1) according to claim 4, characterized in that the stop body (14) is designed in the shape of a sphere.

6. Adjusting device (1) according to one of claims 1, 2, 4, 5, characterized in that the moving pins (7a, 7b) are elastically pre-stressed against one another by means of a return spring (16) designed as a tension spring.

7. The adjusting apparatus (1) according to claim 6, characterized in that the return spring (16) is a helical spring.

8. The adjusting apparatus (1) according to one of claims 1, 2, 4, 5, 7, characterized in that the maximum movement of the centrifugal pieces (5a, 5b) is limited by end stops (24) fitted on the drive wheel (2), respectively.