CN112984002B

CN112984002B - Centrifugal clutch

Info

Publication number: CN112984002B
Application number: CN202011497415.6A
Authority: CN
Inventors: 里昂纳多·特洛西
Original assignee: Yingqingsi Engineering Co ltd
Current assignee: Yingqingsi Engineering Co ltd
Priority date: 2019-12-17
Filing date: 2020-12-17
Publication date: 2023-05-09
Anticipated expiration: 2040-12-17
Also published as: CN112984002A; IT201900024217A1

Abstract

Described is a centrifugal clutch (1) comprising: -a drive shaft (10) rotating about a rotation axis (X); a driven shaft (20) having a bell portion (21), the bell portion (21) being coaxial with the drive shaft (10) and configured to receive at least a portion of the drive shaft (10); and a clutch body (30) that rotates integrally with the drive shaft (10) and is capable of engaging with the driven shaft (20). The clutch body (30) comprises at least two centrifugal masses (31), the centrifugal masses (31) being movable between a radially inner position and a radially outer position and being configured to adopt a disengaged configuration in which the driven shaft (20) and the driving shaft (10) rotate independently of each other, and an engaged configuration in which the driven shaft (20) and the driving shaft (10) rotate integrally with each other after engagement of the centrifugal masses (31) with the inner surfaces of the bell-shaped portion (21). The centrifugal clutch (1) further comprises an actuating device (40), the actuating device (40) selectively acting on the centrifugal mass (31) and being configured to influence the radial position of the centrifugal mass (31) independently of the rotational speed value of the drive shaft (10).

Description

Centrifugal clutch

Technical Field

The present invention relates to a centrifugal clutch.

In particular, the invention relates to a centrifugal clutch suitable for use in the transportation industry, in particular for mounting on a vehicle, preferably a hybrid vehicle, and for use in manufacturing, in particular for industrial applications.

Background

Especially in the transportation industry, it is very important to ensure maximum efficiency and versatility of the vehicle to reduce energy consumption and pollution.

Furthermore, it is also important to ensure structural simplicity of the equipment making up the vehicle, in order to minimize manufacturing and maintenance costs.

The use of centrifugal clutches typically involves single gear vehicles and continuous automatic gear shifting vehicles.

Centrifugal clutches of this type generally have two functions.

In particular, the centrifugal clutch is configured to connect the driving shaft to the driven shaft to transmit driving torque during acceleration and during running, and vice versa, and to disconnect the driving shaft from the driven shaft to make the driving shaft and the driven shaft independent of each other when the vehicle is decelerating or stationary.

The term "drive shaft" refers to a transmission unit associated with an engine that provides mechanical power from the engine in the form of drive torque.

On the other hand, the term "driven shaft" refers to a transmission unit that is typically integral with the driving wheels of the vehicle.

The centrifugal clutch of the prior art basically has a clutch body firmly connected to a drive shaft, and the clutch body includes a plurality of movable masses configured to radially expand under the centrifugal force generated by rotation of the drive shaft. By extension, the movable mass gradually engages the inner surface of the usual bell, transmitting the driving torque, wherein the bell is integral with the driven shaft.

Vice versa, when the rotation speed of the driving shaft is low, the movable mass is withdrawn, cutting off the mechanical continuity between the driving shaft and the driven shaft.

The mechanism enables the centrifugal clutch to automatically operate, and has various advantages such as simple structure and low production cost.

Furthermore, this solution allows a gradual torque transmission due to the initial sliding between the movable mass and the bell.

Finally, the operation of the centrifugal clutch is not directly controlled, which is beneficial to the overall control of the vehicle.

However, this solution is not without drawbacks.

In particular, due to its structure, the centrifugal clutch is configured to transfer torque in a unidirectional manner.

In other words, torque is transmitted only from the drive shaft to the driven shaft.

Furthermore, if a device, vehicle or machine is equipped with such a clutch, the advantages of automation of the centrifugal clutch may become disadvantageous in order to more effectively or specifically manage the device, vehicle or machine, requiring direct control of the engagement and disengagement of the clutch.

In fact, in order to engage/disengage the clutch, the value of the centrifugal force generated by the rotation needs to be greater/less than the return force exerted by the adaptation spring, which is normally present in the clutch body and is configured to keep the centrifugal mass in a radially inner position, i.e. in a position close to the clutch body.

In other words, the operation of the automatic centrifugal clutch depends only on the rotational speed of the drive shaft, and it cannot be directly managed or controlled.

Disclosure of Invention

Against this background, it is the technical object underlying the present invention to provide a mechanical clutch which overcomes the above-mentioned disadvantages of the prior art.

In particular, it is an object of the present invention to provide a centrifugal clutch which is selectively controllable to improve management while ensuring the same advantages of prior art automatic operation of the centrifugal clutch.

Furthermore, it is an object of the invention to provide a centrifugal clutch which is substantially kept simple in construction and low in production costs.

The technical aim and the stated objects indicated are basically achieved by a centrifugal clutch comprising a drive shaft rotatable about a rotation axis (X), a transmission shaft and a clutch body, the driven shaft having a bell-shaped portion coaxial with the drive shaft and configured to at least partially house the drive shaft, the clutch body being integrally rotatable with the drive shaft and engageable with the driven shaft.

In particular, the clutch body comprises at least two centrifugal masses movable between a radially inner position, in which the centrifugal masses are close to the rotation axis of the drive shaft and spaced apart with respect to the inner surface of the bell, and a radially outer position, in which the centrifugal masses are moved away from the rotation axis of the drive shaft and in contact with the inner surface of the bell.

The passage from the radially inner position to the radially outer position and vice versa depends on whether a threshold value for the rotational speed of the drive shaft is exceeded.

The clutch body is configured to adopt a disengaged configuration corresponding to a radially inner position of the centrifugal mass, wherein the driven shaft and the drive shaft rotate independently, and an engaged configuration corresponding to a radially outer position of the centrifugal mass, wherein the driven shaft and the drive shaft rotate integrally with each other upon engagement of the centrifugal mass and the bell-shaped portion inner surface.

The centrifugal clutch further comprises an actuation device selectively acting on the centrifugal mass and configured to influence the radial position of the centrifugal mass independently of the rotational speed value of the drive shaft.

Advantageously, by using the actuation means, a change in the configuration of the clutch body can be selectively controlled directly.

Drawings

The technical features of the present invention have been explicitly described in the accompanying claims with reference to the above objects and their advantages are also more apparent by the following detailed description, with reference to the accompanying drawings, which show preferred, non-limiting embodiments of the invention, in which:

FIG. 1 is a side cross-sectional view of an embodiment of a centrifugal clutch according to the invention;

FIG. 2 is a front cross-sectional view of the embodiment of the centrifugal clutch of FIG. 1 according to the present invention;

FIG. 3 is a detailed side cross-sectional view of the centrifugal clutch of FIGS. 1 and 2 in one operative configuration;

FIG. 4 is a detailed side cross-sectional view of the centrifugal clutch of FIGS. 1 and 2 in another operating configuration;

fig. 5 is a detailed side sectional view of the centrifugal clutch of fig. 1 and 2 in another operating configuration.

Detailed Description

Preferred, non-limiting embodiments of the present invention will now be described with reference to fig. 1-5.

Referring to the drawings, reference numeral 1 denotes a centrifugal clutch according to the present invention as a whole, which will be referred to as "clutch 1" hereinafter.

As shown in fig. 1, the clutch 1 generally includes a drive shaft 10, a clutch body 30 integrally rotating with the drive shaft 10, and a driven shaft 20, and the driven shaft 20 may be engaged with the clutch body 30 and have a bell portion 21.

In particular, the bell portion 21 is coaxial with the drive shaft 10 and is configured to at least partially house the drive shaft 10.

The drive shaft 10 rotates in a constrained manner about a respective axis of rotation "X".

Furthermore, the drive shaft 10 is configured to transmit mechanical power, in particular drive torque, to the clutch 1.

The mechanical power is supplied to the drive shaft 10 by a motor (not shown in the drawings).

The drive shaft 10 rotates integrally with the clutch body 30.

Structurally, the clutch body 30 preferably has a drum shape or a plate shape, as shown in fig. 2.

The clutch body 30 comprises at least two centrifugal masses 31 positioned on the clutch body 30 at equal angular distances from each other.

The centrifugal mass 31 is movable between a radially inner position and a radially outer position.

In a preferred embodiment, the clutch body 30 comprises three centrifugal masses 31, which three centrifugal masses 31 are pivotally connected to the clutch body 30 by respective connecting means of respective outer edge portions of the clutch body 30.

In particular, according to a preferred embodiment, the centrifugal masses 31 are tilted about respective tilt axes between a radially inner position and a radially outer position, wherein the tilt axes are preferably parallel to the rotation axis "X" of the drive shaft 10.

As shown in fig. 3, in a radially inner position, the centrifugal mass 31 is close to the rotation axis "X" of the drive shaft 10 and spaced apart with respect to the inner surface of the bell portion 21 of the driven shaft 20.

In particular, in this position, the centrifugal mass 31 is at least partially attached to the clutch body 30.

Advantageously, according to a preferred embodiment, the clutch body 30 comprises a drive unit 34, preferably a drive spring, for each centrifugal mass 31.

In particular, in the preferred embodiment, there are three drive units 34.

The drive unit 34 is configured to generate a force designed to keep the respective centrifugal mass 31 towards the radially inner position, so as to make the radially inner position more stable.

On the other hand, as shown in fig. 4, in the radially outer position, the centrifugal mass 31 is moved away from the rotation axis "X" of the drive shaft 10 and is in contact with the inner surface of the bell portion 21.

During automatic use of the clutch 1, the radially inner and radially outer positions of the centrifugal mass 31 depend on the operating conditions, in particular on the number of revolutions of the drive shaft 10.

More specifically, the rotation of the drive shaft 10 (and of the clutch body 30 rotating integrally therewith) generates a centrifugal force, which acts to move the centrifugal mass 31 towards a radially external position, contrary to the action of the drive unit 34.

In other words, below a predetermined number of revolutions of the drive shaft 10, the centrifugal force generated on the centrifugal mass 31 is insufficient to overcome the force exerted by the drive unit 34. Thus, the centrifugal mass 31 remains in a radially inner position.

Vice versa, above a predetermined motor revolution, the centrifugal force generated on the centrifugal mass 31 is greater than the force exerted by the drive unit 34. Thus, the centrifugal mass 31 is in a radially outer position.

The clutch body 30 integrates the drive shaft 10 and the driven shaft 20 by this mechanism.

In particular, the clutch body 30 is configured to adopt a disengaged configuration and an engaged configuration.

In the disengaged configuration, as shown in fig. 3, the clutch body 30 is not engaged with the driven shaft 20, corresponding to the radially inner position of the centrifugal mass 31, so as to rotate the driven shaft 20 and the driving shaft 10 independently of each other.

In other words, since the centrifugal mass 31 is located at a radially inner position, there is no mechanical continuity between the driving shaft 10 and the driven shaft 20.

On the other hand, as shown in fig. 4, in the engaged configuration, the driven shaft and the driving shaft are rotated integrally corresponding to the radially outer position of the centrifugal mass 31.

In this configuration, the centrifugal mass 31 remains urged in the radial direction toward the inner surface of the bell portion 21 under the centrifugal force described above. Friction generated between the centrifugal mass 31 and the inner surface of the bell portion 21 integrates the clutch body 30 with the driven shaft 20, giving mechanical continuity between the driving shaft 10 and the driven shaft 20.

Advantageously, the inner surface of the bell portion 21 may be coated with a friction material to increase the coefficient of friction.

Likewise, the surface of the centrifugal mass 31 that is in contact with the inner surface of the bell portion 21 may also be coated with a suitable coating made of a material suitable for increasing the coefficient of friction.

The clutch 1 further comprises an actuating device 40.

The actuating means 40 selectively act on the centrifugal mass 31 and are configured to influence its position.

In particular, the actuation means 40 operate independently of the rotational speed value of the drive shaft 10.

In this specification, the term "influence" refers to the dual influence of switching and/or maintaining the configuration of the clutch body 30.

In particular, the actuating means 40 are configured to switch the clutch body 30 between a disengaged configuration and an engaged configuration, changing the position of the centrifugal mass 31 in a radially inner position and in a radially outer position, independently of the rotational speed value of the drive shaft 10.

For example, when the clutch body 30 is in the engaged configuration, the actuating device 40 can switch configurations by changing the position of the centrifugal mass 31.

In other words, even if the number of revolutions of the driving shaft 10 is greater than the predetermined number of revolutions, the centrifugal force overcomes the force of the driving unit 34, and the actuating device 40 can move the centrifugal mass 31 away from the bell portion 21, causing the driven shaft 20 to rotate independently.

Vice versa, when the clutch body 30 is in the disengaged configuration, the actuation means 40 can operate the clutch body 30, transforming the clutch body 30 from the disengaged configuration into the engaged configuration, even if the number of revolutions of the drive shaft 10 is lower than a predetermined number of revolutions, which allows the engaged configuration of the clutch body 30 at the time of automatic operation.

Furthermore, the actuating means 40 are configured to maintain the clutch body 30 in one of the disengaged and engaged configurations and to maintain the centrifugal mass 31 in the corresponding position, irrespective of variations in operating conditions.

In other words, the actuating means are able to maintain the position of the centrifugal mass 31, irrespective of the variation in the number of revolutions of the drive shaft 10.

For example, if the number of revolutions of the drive shaft 10 is initially greater than a predetermined number of revolutions and then suddenly becomes smaller than the predetermined number of revolutions, the centrifugal mass 31 may tend to be at a radially inner position and no longer in contact with the bell portion 21 at the time of automatic operation.

In this case, however, the actuating means 40 are able to keep the centrifugal mass 31 in a radially external position, thus preserving the mechanical continuity between the driving shaft 10 and the driven shaft 20.

The clutch 1 can advantageously be used for hybrid propulsion vehicles (internal combustion engines and electric drives).

Constructed in this way, for example, the clutch 1 can be used to integrate the driven shaft 20 with the drive shaft 10 associated with the motor.

In effect, the electric machine acts as a brake when braking, converting mechanical power from the driven shaft 20 into energy stored in the vehicle battery.

Structurally, the actuating means 40 comprise an actuating member 41, rotating integrally with the clutch body 30.

The actuating member 41 has a pair of

engagement portions

42a,42b for the centrifugal masses 31, a pair of

engagement portions

42a,42b for each centrifugal mass 31.

Furthermore, since the clutch body 30 and the actuating member 41 are integrally rotated, each pair of

engagement portions

42a,42b will be associated with a single centrifugal mass 31 and act on that centrifugal mass 31.

In particular, each pair of

engagement portions

42a,42b has a first engagement portion 42a and a second engagement portion 42b configured to selectively and reversibly engage the same centrifugal mass 31.

The actuating member 41 is axially slidable relative to the clutch body 30.

In particular, the actuating member 41 is axially slidable with respect to the clutch body 30 along a direction parallel to the rotation axis "X" of the drive shaft 10.

The actuating member 41 is movable at least between a first position, a second position and an intermediate position between the first and second positions.

As shown in fig. 3, in the first position, the first engagement portion 42a of the actuating member 41 maintains the respective centrifugal mass 31 in a radially inner position, corresponding to the disengaged configuration of the clutch body 30.

In other words, irrespective of the number of revolutions of the drive shaft 10, the actuating member 41 forces the centrifugal mass 31 into a radially inner position.

In the second position, corresponding to the engaged configuration of the clutch body 30, the second engagement portion 42b of the actuating member 41 retains the respective centrifugal mass in a radially external position, as shown in fig. 4.

In other words, irrespective of the number of revolutions of the drive shaft 10, the actuating member 41 forces the centrifugal mass 31 into a radially outer position.

Finally, as shown in fig. 1 and 5, in the intermediate position, the first engagement portion 42a and the second engagement portion 42b are not engaged with the respective centrifugal masses 31.

Thus, when the actuating member 41 is in the neutral position, the clutch 1 will operate automatically, and in particular the configuration adopted by the clutch body 30 will depend on the number of revolutions of the drive shaft 10.

In a preferred embodiment, the

engagement portions

42a,42b are located on axially opposite sides of the respective centrifugal mass 31, engaging the centrifugal mass 31 at

opposite faces

32a, 32 b.

In particular, the actuating member 41 includes a first plate 44a and a second plate 44b facing respective opposite faces of the clutch body 30.

In general, the first plate 44a and the second plate 44b include the first engaging portion 42a and the second engaging portion 42b, respectively, in an integrated manner.

The first plate 44a and the second plate 44b are rigidly connected to a connecting element 45, the connecting element 45 extending in a direction parallel to the axis of rotation "X".

Preferably, the connecting element 45 comprises 3 bars, positioned in a radially equidistant manner.

Each centrifugal mass 31 preferably has a first housing recess 33a and a second housing recess 33b.

A first housing recess 33a is formed on the first face 32a of the centrifugal mass 31 at a first radial position.

On the other hand, the second housing recess 33b is formed on the second face 32b of the centrifugal mass 31 at a second radial position, the second face 32b being axially opposite to the first face 32 a.

Alternatively, according to other possible embodiments not shown in the figures, the

engagement portions

42a,42b are positioned in engagement with the respective centrifugal mass 31 on the

same face

32a, 32 b.

In this embodiment, both housing recesses 33a and 33b are formed on the

same face

32a or 32b of the respective centrifugal mass 31.

In general, the first engagement portion 42a has a raised portion 43, the raised portion 43 being configured to be inserted into the housing recess 33a when the clutch body 30 is in the disengaged configuration.

Likewise, the second engagement portion 42b has a raised portion 43, the raised portion 43 being configured to be inserted into the second housing recess 33b when the clutch body 30 is in the engaged configuration.

The first and second housing recesses 33a and 33b and the convex portions 43 of the first and

second engagement portions

42a and 42b have shapes such that the respective centrifugal masses 31 are radially moved after one of the convex portions 43 is axially inserted into the respective first or second housing recess 33a or 33b.

In other embodiments not shown in the drawings, the housing recesses 33a and 33b are formed on the

respective engagement portions

42a and 42b, while the corresponding raised portions 43 are formed on the

respective faces

32a and 32b of the centrifugal mass 31.

Preferably, the first housing recess 33a and the second housing recess 33b have a truncated cone shape, and the protruding portion 43 of the first engaging portion 42a and the second engaging portion 42b has a substantially slope shape, and the protruding portion 43 is configured to gradually engage/disengage with the first housing recess 33a or the second housing recess 33b when moving toward/away from the first or second position of the actuating member 41.

According to other embodiments, the protruding portions 43 of the first and second

engaging portions

42a,42b have a sliding mechanism, preferably with a small friction force, such as a bearing.

The actuating means 40 further comprises a control unit 46 associated with the actuating member 41 for moving it between the first and second positions.

The control unit 46 is coaxial with the drive shaft 10.

Further, a control unit 46 is associated with the actuating member 41 to rotate integrally with the clutch body 1.

In other words, the control unit 46 is preferably integral with the device, vehicle or machine in which it is inserted, while the actuation member 41 is coaxial with the drive shaft 10 and therefore rotates with respect to the device, vehicle or machine.

The control unit 46 further comprises a manual control (not shown in the drawings) configured to trigger movement of the actuating member 41 between the first and second positions.

Furthermore, the control unit 46 may also comprise a controlled actuator and an opposing control unit (not shown in the figures).

The unit may be configured to operate automatically in accordance with at least one operating parameter of the device, vehicle or machine in which the clutch 1 is installed, which operating parameter is calculated by the control unit on the basis of the measured values of the sensors, wherein these measured values are continuously adjusted by the control unit.

In this way, the control unit enables the control unit 46 to translate the actuating member 41.

Advantageously, the present invention overcomes the drawbacks of the prior art by providing a centrifugal clutch 1 that achieves the preset aims, the centrifugal clutch 1 being able to selectively control the centrifugal clutch 1 to improve management and efficiency while guaranteeing the same advantages as those brought about by the automatic operation of the centrifugal clutch 1 of the prior art.

In fact, thanks to the presence of the actuating means 40, it is possible to selectively control the clutch 1 directly, adapting it to the particular application in which such control is required.

Furthermore, the centrifugal clutch according to the invention has a simple, optimized structure, so that lower production and installation costs can be achieved.

Claims

1. Centrifugal clutch (1), comprising:

-a drive shaft (10) rotatable about a rotation axis (X);

-a driven shaft (20) having a bell portion (21), the bell portion (21) being coaxial with the drive shaft (10) and configured to at least partially house the drive shaft (10);

-a clutch body (30) rotating integrally with the drive shaft (10) and being capable of engaging with the driven shaft (20); the clutch body (30) comprises at least two centrifugal masses (31), the centrifugal masses (31) being movable between a radially inner position, in which the centrifugal masses (31) are close to the rotation axis (X) of the drive shaft (10) and spaced apart with respect to the inner surface of the bell-shaped portion (21), and a radially outer position, in which the centrifugal masses (31) are moved away from the rotation axis (X) of the drive shaft (10) and in contact with the inner surface of the bell-shaped portion (21), wherein the passage of the centrifugal masses (31) from the radially inner position to the radially outer position depends on whether or not a rotational speed threshold of the drive shaft (10) is exceeded;

the clutch body (30) is configured to adopt a disengaged configuration and an engaged configuration, wherein the disengaged configuration corresponds to a radially inner position of the centrifugal mass (31), wherein the driven shaft (20) and the drive shaft (10) are rotated independently; the engagement formation corresponds to a radially outer position of the centrifugal mass (31), wherein the driven shaft (20) and the driving shaft (10) rotate integrally after the centrifugal mass (31) is engaged with an inner surface of the bell portion (21);

characterized in that it further comprises actuation means (40), which actuation means (40) selectively act on said at least two centrifugal masses (31) and are configured to influence the radial position of said centrifugal masses (31) independently of the value of the rotational speed of said drive shaft (10).

2. Centrifugal clutch (1) according to claim 1, wherein the actuation means (40) are configured to switch the clutch body (30) between the disengaged configuration and the engaged configuration, changing the position of the centrifugal mass (31) between the radially inner position and the radially outer position independently of the rotational speed value of the drive shaft (10).

3. Centrifugal clutch (1) according to claim 1, wherein the actuation means (40) are configured to hold the clutch body (30) in one of the disengaged or engaged configuration, the position of the centrifugal mass (31) being held in one of the radially inner or radially outer position independently of the rotational speed value of the drive shaft (10).

4. A centrifugal clutch (1) according to claim 3, wherein the actuating means (40) comprise an actuating member (41), which actuating member (41) rotates integrally with the clutch body (30) and has a pair of engagement portions (42 a,42 b) for each of the at least two centrifugal masses (31); each pair of engagement portions (42 a,42 b) is provided with a first engagement portion (42 a) and a second engagement portion (42 b) configured to selectively and reversibly engage with the same centrifugal mass (31).

5. Centrifugal clutch (1) according to claim 4, wherein the actuating member (41) slides axially with respect to the clutch body (30) between:

a first position, corresponding to said separated configuration, wherein said first engagement portion (42 a) keeps the respective centrifugal mass (31) in said radially inner position,

a second position, corresponding to said engagement configuration, wherein said second engagement portion (42 b) keeps the same centrifugal mass (31) in said radially external position;

an intermediate position between the first and second positions, wherein the first and second engagement portions (42 a,42 b) are not engaged with the respective centrifugal mass (31), and wherein

The actuation means (40) comprises a control unit (46) associated with the actuation member (41) for moving it between the first and the second position.

6. Centrifugal clutch (1) according to claim 5, wherein the first engagement portion (42 a) and the second engagement portion (42 b) are located on axially opposite sides of the respective centrifugal mass (31) for engaging the centrifugal mass (31) at opposite faces (32 a, 32 b).

7. Centrifugal clutch (1) according to claim 5 or 6, wherein each of the at least two centrifugal masses (31) has a first housing recess (33 a) and a second housing recess (33 b), the first housing recess (33 a) being formed in a first face (32 a) of the centrifugal mass (31) in a first radial position, the second housing recess (33 b) being formed in a second face (32 b) of the centrifugal mass (31) in a second radial position, the second face (32 b) being axially opposite to the first face (32 a),

wherein the first engagement portion (42 a) has a protruding portion (43), the protruding portion (43) being configured to be inserted into the first housing recess (33 a) when the clutch body (30) is in the disengaged configuration, and wherein the second engagement portion (42 b) has a protruding portion (43), the protruding portion (43) being configured to be inserted into the second housing recess (33 b) when the clutch body (30) is in the engaged configuration.

8. Centrifugal clutch (1) according to claim 7, wherein the first and second housing recesses (33 a, 33 b) and the protruding portions (43) of the first and second engagement portions (42 a,42 b) have a shape enabling radial movement of the centrifugal mass (31) after axial insertion of one of the protruding portions (43) into the respective first or second housing recess (33 a, 33 b).

9. Centrifugal clutch (1) according to claim 8, wherein the first and second housing recesses (33 a, 33 b) have a truncated cone shape, and wherein the protruding portion (43) of the first and second engagement portion (42 a,42 b) has a substantially ramp-like or sliding mechanism, such as a bearing, which protruding portion (43) is configured to gradually engage/disengage with the first housing recess (33 a) or the second housing recess (33 b) upon moving towards/away from the first and second positions of the actuation member (41).

10. Centrifugal clutch (1) according to claim 9, wherein the control unit (46) is coaxial with the drive shaft (10), and wherein the actuation member (41) is associated with the control unit (46) such that it rotates with the clutch body (30).

11. Centrifugal clutch (1) according to claim 10, wherein the control unit (46) comprises a manual control configured to trigger the movement of the actuation member (41) between the first and second positions.

12. Centrifugal clutch (1) according to claim 11, wherein the actuation member (41) comprises a first and a second plate (44 a, 44 b) facing respective opposite faces of the clutch body (30); said first and second plates (44 a, 44 b) respectively include said first and second engagement portions (42 a,42 b) in an integral form;

the first and second plates (44 a, 44 b) are rigidly connected to a connecting element (45), the connecting element (45) extending in a direction parallel to the rotation axis (X).