EP2859167A1

EP2859167A1 - Motorized system for controlling the movement of a leaf for opening and closing an opening in a wall

Info

Publication number: EP2859167A1
Application number: EP13737392.4A
Authority: EP
Inventors: Gianni Michielan
Original assignee: CAME GROUP SpA
Current assignee: CAME GROUP SpA
Priority date: 2012-06-07
Filing date: 2013-05-27
Publication date: 2015-04-15
Anticipated expiration: 2033-05-27
Also published as: ITTO20120497A1; EP2859167B1; RU2014149008A; RU2623964C2; ES2604583T3; WO2013182947A1

Abstract

The system (10) comprises: an actuator or motor (14) adapted to be secured to a wall (P); and a rotatable element (16) adapted to be constrained to a leaf (A) and to be rotated about an actuation axis (X-X) by means of the actuator or motor (14), in such a way as to move the leaf (A) in order to open and/or close an opening (F). The system further comprises disengageable transmission means (18), which comprise a drive portion (20) and a driven portion (22) rotatably cooperating with the actuator or motor (14) and with the rotatable element (16), respectively, and which can be placed in: a disengaged condition, wherein they are rotatably independent of each other and movable among a plurality or predetermined mutual arrangements, each one of the mutual arrangements corresponding to an associated angular position that can be taken by the leaf (A) with respect to the opening (F); and an engaged condition, wherein they rotatably cooperate together and are locked into a mutual arrangement which can be selected among the plurality of predetermined mutual arrangements.

Description

MOTORIZED SYSTEM FOR CONTROLLING THE MOVEMENT OF A LEAF FOR OPENING AND CLOSING AN OPENING IN A WALL

5 DESCRIPTION

Technical field

The present invention relates to a motorized control system for controlling the movement of at least one leaf intended for opening or closing, at least partially, an0 opening, such as a window, in a wall.

Such systems are generally much appreciated, particularly when applied to windows, in that they allow a user to automatically open or close the shutters without having to manually push said shutters or lean out of the5 window.

Background art

More specifically, the present invention relates to a system according to the preamble of the appended claim 1, i.e. a system of the above-mentioned type comprising:

0 - an actuator or motor device adapted to be secured to said wall; and

a rotatable element adapted to be constrained to said leaf and to be rotated about an actuation axis by means of said actuator or motor device, in such a way as to move5 said leaf in order to open and/or close said opening.

However, systems of this type suffer from a few drawbacks .

One drawback is that the actuator or motor device and the rotatable element are rigidly connected and constrained0 to each other in rotation to allow the exertion of an appropriate thrust or pull on the leaf in order to cause it to open or close, and they cannot be decoupled for manually moving the leaf.

This situation proves to be uncomfortable especially in the event of a malfunction of the actuator device or an interruption of the power supply to the system. In both of these cases, the leaf will stay locked in the position it was in prior to the malfunction or the power blackout, and it cannot be brought manually into the desired position until the actuator device is repaired or power is restored.

This operation becomes even more complex when the actuator or motor device is protected by enclosures, implying the necessity of disassembling the rotatable element from the output shaft of the actuator or motor device and then removing enclosure components to be able to properly work on the system.

Summary of the invention

It is one object of the present invention to provide a system which can overcome this and other drawbacks of the prior art, while at the same time being simple and economical to manufacture.

According to the present invention, this and other objects are achieved through a system made in accordance with the appended claim 1.

It is understood that the appended claims are an integral part of the technical teachings provided in the following detailed description of the invention.

Brief description of the drawings

Further features and advantages of the present invention will become apparent from the following detailed description, which is supplied by way of non-limiting example with reference to the annexed drawings, wherein:

Figure 1 is a front elevation view of a window fitted with an exemplificative embodiment of a system according to the present invention;

Figure 2 is an exploded perspective view of the system shown in Fig . 1 ;

Figure 3 is an enlarged partial perspective view of the system shown in the preceding figures;

Figure 4 is an enlarged perspective view of some implementation details of the system, indicated by line IV in Figure 3 ;

Figures 5 and 6 are partial perspective views of the system shown in the preceding figures, which includes transmission means shown in an engaged condition and in a disengaged condition, respectively; and

Figures 7 and 8 are longitudinal sectional views of a part of the system shown in Figure 5 and Figure 6, respectively.

Detailed description of the invention

With reference to Figure 1, numeral 10 designates as a whole an exemplificative embodiment of a system according to the present invention.

System 10 is designed for motorized control of the movement of at least one leaf A adapted for opening or closing, at least partially, an opening F in a wall P.

In the embodiment shown in Figure 1, the above- mentioned opening is a window F that can be closed or opened by a pair of leaves A which are movably mounted to wall P in the vicinity of opposite sides of window F. However, as will become apparent to a man skilled in the art from the following description, the system of the present invention is also applicable to different configurations; for example, it may control the movement of a single leaf adapted to close the entire opening defined through the wall. Furthermore, the system of the invention is not only applicable for opening or closing leaves of windows, since it can also be used for opening or closing leaves associated with doors or other openings in a generic wall.

In addition, in the illustrated embodiment each leaf A is mounted to wall P in such a manner that it can swivel. Preferably, the structure of leaf A mounted to wall P is of the one-piece type; however, the system of the present invention is also suitable for use on leaves of a different type, e.g. of the so-called "Paduan" type (where leaf portions can be folded outwards from opening F) . By using a suitable transmission mechanism, it is also conceivable to use the system in combination with sliding leaves, e.g. of 'the type "hiding" into wall P) .

Furthermore, in the illustrated embodiments leaves A are shutters, i.e. they are "solid", their wall having no apertures or interruptions; as an alternative, the leaves may also be in the form of louvers, i.e. with apertures or interruptions through which light from the outside can enter the room. As is known in the industry, the apertures or interruptions in such louver-type leaves can be obtained through a plurality of transverse boards stacked parallel to one another, slightly inclined relative to the plane defined by the leaf itself.

In Figure 1, leaves A adapted to close window F are shown in the wide open position.

With particular reference to Figures 2 and 3, system 10 comprises:

an actuator o motor device 14 adapted to be mounted to wall P in the proximity of opening F, preferably by means of a support structure 12 whereon it is prearranged for being supported or hung; and a rotatable element 16, e.g. an arm, adapted to be constrained to leaf A and to be rotated about an actuation axis X-X by means of actuator or motor device 14, in such a way as to move leaf A in order to open and/or close opening F.

As already described, in the illustrated embodiment leaf A can swivel because it is hingedly mounted to wall P.

System 10 further comprises disengageable transmission means, designated as a whole 18, which comprise a drive portion 20 and a driven portion 22 rotatably cooperating with actuator or motor device 14 and with rotatable element 16, respectively. Drive portion 20 and driven portion 22 can be placed in:

a disengaged condition (Figures 6 and 8) , wherein they are rotatably independent of each other and movable relative to each other among a plurality of predetermined mutual arrangements, each one of said mutual arrangements corresponding to an associated angular position that can be taken by leaf A; and

- an engaged condition (Figures 5 and 7) , wherein they rotatably cooperate together in a mutual arrangement which can be selected among said plurality of predetermined mutual arrangements and which corresponds to a desired angular position of leaf A.

Thanks to the presence of transmission means 18, even an unskilled user can make a manual adjustment of the angular position of leaves A in the event of a malfunction of motor device 14 or an interruption of the power supply to said motor 14. In fact, the user can switch drive portion 20 and driven portion 22 from the engaged condition (of normal use) to the disengaged condition (of adjustment) and move them in such a way as to cause them to take the mutual arrangement corresponding to the desired angular position of leaf A. Then the user can bring drive portion 20 and driven portion 22 again into the engaged condition, wherein they rotatably cooperate together and are locked into the selected mutual arrangement .

The illustrated embodiment shows a merely exemplificative way of mounting support structure 12 and actuator or motor device 14 to wall P. In this embodiment, the actuator or motor device 14 is mounted to the top edge or "lintel" of opening F. For example, said actuator or motor device 14 is secured to wall P through a support structure 12 made out of a metal section preferably comprising mounting holes (not numbered) that allow it to be fastened to wall P by means of screws; in particular, when mounting support structure 12 to wall P it is possible to use a j ig M with guide holes (not numbered) located in positions corresponding to said mounting holes. This makes it possible to drill beforehand a plurality of holes into wall P (e.g. at the top edge of opening A) exactly where indicated by the guide holes in jig M, which is useful to ensure better precision when mounting support structure 12 to wall P.

In the illustrated embodiment, actuator or motor device 14 is substantially hung on support structure 12, e.g. mounted thereto by means of screws. Preferably, device 14 is a continuously operating motor, but in less preferred variants it may be an actuator operating in a discontinuous or discrete mode. In particular, device 14 is an electric motor, e.g. a motoreducer, fitted with an output shaft 15 adapted to transfer to rotatable element 16 a rotary motion about actuation axis X-X via transmission means 18. In a per se known manner, actuator or motor device 14 is adapted to be controllably operated by a control unit adapted to be governed by the user through suitable control devices, possibly remote ones, such as push-buttons, remote controls or domotic equipment.

In the illustrated embodiment, rotatable element 16 is an arm rotatable about actuation axis X-X and connected on one side to actuator or motor device 14, in particular to output shaft 15, via the transmission means, and on the other side to associated leaf A via a suitable guide mechanism. Preferably, said guide mechanism comprises, in a way per se known in the industry, a slider 17 rotatably pivoted to the end of arm 16, and a guide or rail G mounted to leaf A, to which rail slider 17 is slidably coupled, in particular in straight motion.

Preferably, system 10 includes a protective enclosure made out of one or more boxed elements or cases 19 adapted to protect actuator or motor device 14 and possibly also said control unit. In the illustrated example, protective enclosure 19 can be at least partly secured to support structure 12, so as to be at least partly superimposed on actuator or motor device 14. Boxed elements 19 may be arranged side by side and include intermediate sections, e.g. "C" sections, so as to enclose actuator or motor device 14 and protect it like a "shell" against the action of external agents, such as dust, moisture, heat, etc. In such a case, a hole 19a may be present to allow the or motor device 14 to protrude from enclosure 19, e.g. with its output shaft 15 only.

Preferably, drive portion 20 and driven portion 22 are rotatable about the same rotation axis X-X. In the illustrated embodiment, rotation axis X-X and actuation axis X-X coincide. As will be appreciated by a man skilled in the art, in further variant embodiments the rotation axes of the drive portion and of the driven portion may not coincide with each other or with the actuation axis of the rotatable element; for example, such axes may be parallel to one another, or possibly oriented perpendicularly to the actuation axis, through the interposition of more or less complex kinematic mechanisms (e.g. bevel gears or the like) .

In the illustrated embodiment, drive portion 20 and driven portion 22 are elements which are distinct from associated actuator or motor device 14 and from associated rotatable element 16. In further variant embodiments, instead, the drive portion and the driven portion can be manufactured as one piece with the output shaft of the actuator or motor device and with the rotatable element, respectively. Such a design is however less preferred for maintenance reasons, since the entire output shaft or the entire rotatable element will have to be replaced should the drive portion or the driven portion break or malfunction.

Preferably, drive portion 20 and driven portion 22 are mutually movable in a guided manner parallel to rotation axis X-X between the engaged condition, wherein they are abutted and rotatably cooperating, and the disengaged condition, wherein they are set apart and rotatably independent .

In the embodiment shown by way of example in Figures 2 and 3, when drive portion 20 and driven portion 22 are in the engaged condition or in the disengaged condition, they are, respectively, in mutual contact, preferably in the direction of rotation axis X-X, or detached from each other, preferably in the direction of rotation axis X-X. Preferably, drive portion 20 and driven portion 22 have an interface consisting of respective contact surfaces 24 and 26 facing each other, e.g. axially, and having a substantially matching shape, which are adapted to engage one into the other in a plurality of coupling configurations corresponding to said mutual arrangements.

Preferably, each contact surface 24, 26 has a plurality of seats and/or protrusions arranged peripherally with respect to rotation axis X-X and adapted to be coupled, in each one of said mutual arrangements of drive portion 20 and driven portion 22, to respective matching protrusions and/or seats on the other contact surface 26, 24.

In the illustrated embodiment, each contact surface 24, 26 has an alternated succession of said seats and protrusions, which are adapted to be coupled, in each one of said mutual arrangements, to matching protrusions and seats, respectively, on the other contact surface 26, 24.

In the illustrated embodiment, the seats are radial grooves, whereas the protrusions are radial reliefs. In particular, said grooves and reliefs are arranged in a sunburst pattern on the respective drive portion 20 and/or on the respective driven portion 22.

Said alternated succession of grooves and reliefs is preferably obtainable, for example, through a spline machining process carried out on axially opposed faces of drive portion 20 and of driven portion 22. Particularly but not necessarily, the grooves and reliefs of transmission means 18 have a substantially triangular cross-section.

In the illustrated embodiment, contact surface 24 or

26 occupies a peripheral region of associated drive portion 20 or of associated driven portion 22, in particular defining an annular or circumferential area with said alternated succession of grooves and reliefs. In this manner, said peripheral alternated succession defines a peripheral profile substantially having a "saw-tooth" shape (also called "crown toothing") .

In the illustrated embodiment, drive portion 20 and driven portion 22 have a disk-like shape. In particular, such disks, preferably annular in shape, have a substantially circular profile, with the same diameter for both portions 20, 22 of transmission means 18. For example, contact surfaces 24 and 26 are circular crowns, slightly protruding axially from the remaining parts of the disks defined the portions 20, 22.

Preferably, drive portion 20 and driven portion 22 are supported by output shaft 15 and relatively slidable thereon between the engaged condition and the disengaged condition. In the illustrated embodiment, drive portion 20 is rotatably constrained to output shaft 15, while driven portion 22 can be rotatably constrained to drive portion 20 but is rotatably unconstrained from the motor shaft; drive portion 20 is fixedly mounted on output shaft 15, while driven portion 22 is slidably mounted on output shaft 15, parallel to rotation axis X-X.

In the illustrated embodiment, drive portion 20 has an axial through aperture 28 of polygonal shape, e.g. square, which is adapted to be coupled to a tapered intermediate portion 30 of output shaft 15, having a polygonal shape matching axial aperture 28. In particular, the peripheral crown defined by contact surface 24 extends around axial aperture 28. This coupling contributes to firmly constraining together in rotation output shaft 15 and drive portion 20. In the illustrated embodiment, drive portion 20 has at least one pair of socket -head screws or dowels 31 housed in corresponding transversal holes 32 angularly equidistant from each other along the periphery of drive portion 20, e.g. in intermediate section 30. During assembly, socket - head screws 31 are tightened against the periphery of output shaft 15, preferably into cavities (not numbered) transversally obtained therein. This coupling contributes to preventing drive portion 20 from undesirably translating relative to output shaft 15.

In the illustrated embodiment, driven portion 22 has an axial through aperture 36 crossed by output shaft 15, so as to allow relative rotation between driven portion 22 and output shaft 15; in other words, driven portion 22 and output shaft 15 are rotoidally coupled via axial through aperture 36. This ensures a guided coupling between driven portion 22 and output shaft 15, while at the same time allowing relative rotation between them.

In particular, axial through aperture 36 may have a circular cross-section crossed by a distal portion 38 of output shaft 15, which in turn has a cross-section which is substantially complementary to that of axial through aperture 36. Preferably, the transversal extension of distal portion 40 is shorter than that of intermediate portion 30.

In the illustrated embodiment, driven portion 22 is secured to rotatable element or arm 16, particularly at one end 40 thereof. In particular, driven portion 22 has a plurality of axial holes 42 located on the side axially opposite to contact surface 26. Preferably, the coupling between driven portion 22 and rotatable element 16 is effected by means of screws mounted therethrough; in particular, said coupling is effected by tightening the screws through axial holes 42 and orifices 44 present on rotatable element 16, e.g. at end 40, in positions corresponding to those of axial holes 42. In this example, axial holes 42 are angularly equidistant from rotation axis X-X.

In the illustrated embodiment, rotatable element 16 has in its turn an axial through aperture 46, e.g. having a circular cross-section, located in a position corresponding to axial through aperture 36 of driven portion 22. The arrangement and alignment of axial through apertures 36 and 46 is such as to allow output shaft 16 to pass through them, while at the same time ensuring freedom of rotation of the assembly formed by rotatable element 16 and driven portion 22 with respect to said output shaft 16.

In the illustrated embodiment, axial through aperture 46 of rotatable element 16 has a circular cross-section of substantially the same diameter as distal portion 38 of output shaft 15, thus allowing them to slide in a guided manner relative to each other.

With particular reference to Figures 5 to 8 , system 10 may further comprise a control member 48 which can be operated by a user and which is adapted to cause drive portion 20 and driven portion 22 to slide relative to each other between an engaged condition (working position of control member 48) and the disengaged condition (disengaged position of control member 48) . In particular, control member 48 is adapted to cause driven portion 22 to slide over motor shaft 15, away or towards drive portion 20.

Preferably, control member 48 is movably, preferably rotatably, mounted to output shaft 15. In particular, control member 48 is a lever rotatably mounted about an oscillation axis Y-Y in the proximity of the free end of output shaft 15, particularly of distal portion 38 thereof. For example, oscillation axis Y-Y is substantially perpendicular to rotation or actuation axis X-X.

With particular reference to Figures 7 and 8, control member 48 has a cam profile 50 designed for moving, by pushing them, drive portion 20 and driven portion 22 relative to each other between the engaged condition and the disengaged condition. Preferably, cam profile 50 cooperates with driven portion 22; in particular, cam profile 50 has a lobed portion (not numbered) eccentrically protruding relative to oscillation axis Y-Y and cooperating with driven portion 22 to push it against drive portion 20 into the engaged condition (working position, shown in Figures 5 and 7) , and a non-lobed portion (not numbered) capable of receiving, in abutment thereon, driven portion 22 to move it away from drive portion 20 into the disengaged condition (idle position, shown in Figures 6 and 8) .

In the illustrated embodiment, cam profile 50 has a substantially arched shape, with the longest radius of curvature at the lobed portion and the shortest radius of curvature at the non-lobed portion.

In the illustrated embodiment, control member 48 comprises a handle 52 adapted to be gripped by a user wanting to rotate the control member between the working position and the idle position, and a thrust portion 54, with cam profile 50, coupled to handle 52. Handle 52 and thrust portion 54 are shown as two distinct parts coupled together, but these two elements may also be designed as one monolithic piece.

In the illustrated embodiment, the rotary connection between control member 48 and output shaft 15 is effected via thrust portion 54, which preferably has a substantially fork-like shape. In particular, thrust portion 54 has a central or base region 56 with which handle 52 is associated, and a pair of side branches 58 (one of which is only visible in Figures 7 and 8) protruding on opposite sides of central or base region 56, both of which having cam profile 50. Advantageously, side branches 58 extend on diametrically opposed sides of shaft 28, particularly at distal portion 38 thereof. For example, the rotary coupling about oscillation axis Y-Y may be obtained by diametrically inserting a transversal element 60 through shaft 15, advantageously through distal portion 38 thereof. In particular, transversal element 60 is inserted with freedom of rotation through shaft 15 and secured at its ends to at least one of side branches 58. More particularly, transversal element 60 is a screw inserted through a diametric through hole 62 obtained through shaft 15, e.g. through distal portion 38, and screwed to one of the two side branches 58. In this case, oscillation axis Y-Y will correspond to the axis of transversal element 60.

With particular reference to Figures 5 and 7, when transmission means 18 are in the engaged condition, control member 48 is in the working position. In the illustrated embodiment, when control member 48 is in the working position, it is substantially aligned with output shaft 15, i.e. its prevalent extension is substantially parallel to the rotation or actuation axis

X-X. In this manner, cam profile 50 will have its lobed portion facing towards driven portion 2, thus subjecting it to an axial thrust towards drive portion 20.

With reference to Figures 6 and 8, when on the contrary transmission means 18 are in the disengaged condition, control member 48 is in the idle position. In the illustrated embodiment, when control member 48 is in the idle position, it is substantially perpendicular to output shaft 15, i.e. its prevalent extension is substantially transversal, preferably orthogonal, to rotation axis X-X. In this manner, cam profile 50 will have its non-lobed portion facing towards driven portion 2, thus allowing the latter to move away by gravity from drive portion 20.

In the illustrated embodiment, system 10 further includes an elastic element 62 which tends to retain control member 48 when the latter is in its working position (that is, when transmission means 18 are in the engaged condition) . This avoids that, while moving leaf A under the action of motor 14, the cooperation between drive portion 20 and driven portion 22 might generate an axial thrust undesirably causing control member 48 to rotate towards its idle position (Figures 6 and 8) , thus getting into the disengaged condition.

In the illustrated embodiment, elastic member 62 encircles output shaft 15 and is mounted axially between cam profile 52 of control member 48 and driven portion 22 (in particular in abutment on rotatable element or arm 16) . Particularly, elastic element 62 is a Belleville washer, e.g. with a central aperture crossed with transverse play by output shaft 15, in particular by distal portion 38 thereof .

In the illustrated embodiment, elastic element 62 is axially arranged between thrust portion 54, e.g. at side branches 58, and driven portion 22, e.g. through the additional interposition of rotatable element or arm 16 (particularly end 40 thereof) .

When normally in use, system 10 has transmission means 18 in their engaged condition, so that drive portion 20 and driven portion 22 can cooperate to transfer the rotary motion from motor 14 to leaf A via rotatable element or arm 16 and respective guide or slider G. More in detail, contact surfaces 24 and 26 are kept axially coupled together through the effect of the thrust exerted by the lobed portion of cam profile 50 under the action of control member 48. In the engaged condition, therefore, output shaft 15 is made rotatably integral with rotatable element or arm 16. Of course, depending on the direction of rotation imparted by motor 14, leaves A will move towards a partially or wide open condition (Figure 1) or towards a partially or fully closed condition (not shown) .

Let us now consider the case wherein a user wants to re-adjust the angular position of leaf A by means of system 10 after the first installation. In this situation, the user can operate control member or lever 48 by moving it from the working position, shown in Figures 5 and 7, to the idle position, shown in Figures 6 and 8, against the countering action exerted by elastic element 62. Thus, drive portion 20 and driven portion 22 will no longer be kept with their respective contact surfaces 24 and 26 coupled together, since driven portion 22 will move away from drive portion 20, abutting against the non-lobed portion of cam profile 50, with rotatable element or arm 16 in between. Therefore, rotatable element or arm 16 can be freely turned until leaf A will get into the desired angular position.

Subsequently, in order to put system 10 in operation again it will only be necessary to turn control member or lever 48 to the working position, thereby loading elastic element 62, which will tend to prevent the control member from undesirably returning into the idle position (particularly while electric motor 14 is operating) . Then control member 48 will again cause surfaces 24 and 26 of drive portion 20 and of driven portion 22 to abut against each other, thanks to the thrust exerted by the lobed portion of the profile 52. Note that the alternated succession of transversal grooves and reliefs arranged in a sunburst pattern on contact surfaces 24 and 26 is particularly advantageous, in that it allows for fine angular adjustments of the mutual position of drive portion 20 and driven portion 22, thus allowing them to be accurately adjusted with minimal, almost continuous, angular increments between successive mutual angular arrangements of drive portion 20 and driven portion 22.

Of course, without prejudice to the principle of the invention, the forms of embodiment and the implementation details may be extensively varied from those described and illustrated herein by way of non-limiting example, without however departing from the scope of the invention as set out in the appended claims.

Claims

1. Motorized control system (10) for controlling the movement of at least one leaf (A) for opening or closing, at least partially, an opening, such as a window (F) , in a wall (P) ; said system (10) comprising:

an actuator or motor device (14) adapted to be secured to said wall (P) ; and

a rotatable element (16) adapted to be constrained to said leaf (A) and to be rotated about an actuation axis (X- X) by means of said actuator or motor device (14) , in such a way as to move said leaf (A) in order to open and/or close said opening (F) ;

said system being characterized in that it further comprises disengageable transmission means (18) , which comprise a drive portion (20) and a driven portion (22) rotatably cooperating with said actuator or motor device (14) and with said rotatable element (16) , respectively, and which can be placed in:

a disengaged condition, wherein they are rotatably independent of each other and movable relative to each other among a plurality of predetermined mutual arrangements, each one of said mutual arrangements corresponding to an associated angular position that can be taken by said leaf (A) with respect to said opening (F) ; and

an engaged condition, wherein they rotatably cooperate together and are locked into a mutual arrangement which can be selected among said plurality of predetermined mutual arrangements and which corresponds to the desired angular position of said leaf (A) .

2. System according to claim 1, wherein, when said drive portion (20) and said driven portion (22) are in said engaged condition or in said disengaged condition, they are mutually in contact or at a distance from each other, respectively.

3. System according to claim 1 or 2 , wherein said drive portion (20) and said driven portion (22) have an interface with respective contact surfaces (24, 26) facing each other and having a substantially matching shape, which are adapted to engage with each other in different coupling configurations corresponding to said mutual arrangements.

4. System according to any one of the preceding claims, wherein said drive portion (20) and said driven portion (22) are rotatable relative to one same rotation axis (X- X) .

5. System according to claim 4, wherein said actuation axis (X-X) coincides with said rotation axis (X-X) .

6. System according to claim 4 or 5, wherein each contact surface (24, 26) has a plurality of seats and/or protrusions arranged peripherally with respect to the rotation axis (X-X) and adapted to be coupled, in each one of said mutual arrangements of said drive portion (20) and said driven portion (22) , to respective matching protrusions and/or seats on the other contact surface (26, 24) .

7. System according to claim 6, wherein each contact surface (24, 26) has an alternated succession of said seats and protrusions adapted to be coupled, in each one of said mutual arrangements of said drive portion (20) and said driven portion (22), to respective matching protrusions and seats, respectively, on the other contact surface (26, 24) .

8. System according to claim 6 or 7 , wherein said seats are radial grooves and said protrusions are radial reliefs.

9. System according to any one of claims 4 to 8 , wherein said actuator or motor device (14) has an output shaft (15) for transferring to said rotatable element (16) a rotary- motion about said actuation axis (X-X) through said transmission means (18) ; said drive portion (20) and said driven portion (22) being supported by said output shaft (15) and being allowed to slide relative to each other between said engaged condition and said disengaged condition .

10. System according to any one of the preceding claims, wherein said transmission means (18) further comprise a control member (48) which can be operated by a user and which is adapted to take a working position and an idle position, wherein it brings said drive portion (20) and said driven portion (22) into said engaged condition or into said disengaged condition, respectively.

11. System according to claim 10, wherein said control member (48) has a cam profile (50) designed for mutually pushing said drive portion (20) and said driven portion (22) into said engaged condition, when said control member (48) is in said working position, or into said disengaged condition, when said control member (48) is in said idle position .

12. System according to claims 10 and 11, further comprising an elastic element (62) which tends to retain said control member (48) when the latter is in said working position .