WO2023166162A1

WO2023166162A1 - Floor cleaning machine

Info

Publication number: WO2023166162A1
Application number: PCT/EP2023/055404
Authority: WO
Inventors: Carmine MIRTUONO
Original assignee: Comac S.P.A.
Priority date: 2022-03-04
Filing date: 2023-03-03
Publication date: 2023-09-07
Also published as: IT202200004082A1

Abstract

A floor cleaning machine, which comprises a chassis (2) which can move on the floor and supports in a lower region at least one cylindrical brush (3) with a substantially horizontal axis, which is functionally connected to drive means (4). The cylindrical brush (3) has at least one coupling element (5) which can be detachably engaged by an attachment element (6) connected to the drive means (4). The coupling element (5) comprises an annular body (7) which is fixed coaxially to the axis of the cylindrical brush (3) and defines axially a fastening seat (8) for the attachment element (6). The attachment element (6) comprises a movement head (9) which can be actuated by the drive means (4) with a rotary motion about a rotation axis (9a) and can be coupled detachably with the fastening seat (8), for the rotary entrainment of the cylindrical brush (3) by the movement head (9) about the rotation axis (9a), the movement head comprises expandable engagement means (10) which are adapted to pass between a retracted position, in which they are brought closer to the rotation axis, in order to allow the insertion of the movement head (9) into the fastening seat (8), and an expanded position, in which they are spaced apart from the rotation axis (9a), in order to allow the expandable engagement means (10) to engage at least one abutment region (11) defined in the annular body (7), for the rotary entrainment of the cylindrical brush (3) by the movement head (9).

Description

FLOOR CLEANING MACHINE

The present invention relates to a floor cleaning machine.

Various different types of floor cleaning machines are known, which are used in particular in the industrial field.

A first type of cleaning machines is constituted by machines that are commonly known as sweepers, which usually have, generally, a chassis that can move on the floor, which supports exclusively a cleaning base of the brushing type, which enables the collection of refuse into a refuse bin or waste bin of large dimensions accommodated inside the chassis of the machine.

In particular, the cleaning base of this type of machine is, typically, provided with cylindrical brushes with a horizontal axis, which are operatively connected to drive means that make it possible to rotate the cylindrical brushes about their corresponding axes, so that the cylindrical brushes can perform a mechanical cleaning action on the floor.

Floor cleaning machines are also known, called floor washing and drying machines, which have, typically, a basic chassis that can move on the floor, which supports in a lower region a nozzle for dispensing a washing liquid and at least one brush that acts on the floor, while, in a region at the rear of the brush, according to the advancement direction of the machine, there is a floor wiper, which extends transversely to the advancement direction of the machine, and there is an aspiration port to enable the collection from the floor of the washing liquid and of the dirt removed by the action of the brush.

Machines for washing and drying floors can also have cylindrical brushes with a horizontal axis, in place of the more traditional disc brushes.

By virtue of their structure, floor washing and drying machines make it possible to clean the floor by means of a washing liquid and, secondarily, to collect small debris in a collection bin of reduced dimensions.

A third type of floor cleaning machines is also known, called combined machines, which combine the construction structure typical of a classic washing and drying machine with a footing with cylindrical brushes that is purely for brushing, for collecting debris into a collection bin, which in this case too is located in the chassis of the machine.

Typically, the cylindrical brushes are constituted by a basic shaft, constituted by a hollow cylindrical body, which supports externally a plurality of substantially radially-extending bristles and inside which a coupling element is arranged for the detachable connection of the brush to an attachment element connected to the drive means of the footing.

In particular, such coupling element is constituted by an annular body, commonly called flange, which is fixed coaxially inside the basic shaft of the cylindrical brush and in which a fastening seat is axially defined, which is capable of detachably receiving the attachment element.

In the solutions currently known, the attachment element is constituted, in practice, by a movement head of prismatic or similar shape, and the fastening seat defined in the coupling element is shaped complementarily with respect to the movement head, so as to allow the axial insertion and withdrawal of the movement head into and out of the fastening seat of the coupling element and the possibility to transmit rotary motion from the movement head to the cylindrical brush, when the movement head is inserted in the fastening seat of the coupling element.

The use of attachment elements constituted by prismatic-shaped movement heads has the drawback of requiring, during the application of the cylindrical brushes onto the footing, the operator to first perform the centering, often laborious, between the movement head and the fastening seat defined by the coupling element, so that the movement head and the engagement seat are in the mutual position that allows the insertion of the movement head into the fastening seat.

The aim of the present invention is to provide a floor cleaning machine that is capable of improving the known art in one or more of the above mentioned aspects.

Within this aim, an object of the invention is to provide a floor cleaning machine that enables the operator to very rapidly and simply couple the cylindrical brushes to the drive means of the footing without the need to first perform the centering between the attachment element which is connected to the drive means and the coupling element which is integral with the brush.

Another object of the invention is to provide a floor cleaning machine that is convenient and practical for the user to use.

A further object of the invention is to provide a floor cleaning machine that is capable of offering the widest guarantees of reliability and safety in operation.

Furthermore, the present invention sets out to overcome the drawbacks of the background art in a manner that is alternative to any existing solutions.

Another object of the invention is to provide a floor cleaning machine that is highly reliable, easy to implement and of low cost.

This aim and these and other objects which will become more apparent hereinafter are achieved by a floor cleaning machine according to claim 1, optionally provided with one or more of the characteristics of the dependent claims.

Further characteristics and advantages of the invention will become better apparent from the description of a preferred, but not exclusive, embodiment of the machine according to the invention, which is illustrated by way of non-limiting example in the accompanying drawings wherein:

Figure 1 is a partially cutaway and transparent perspective view of the machine according to the invention, with some parts omitted for the sake of simplicity;

Figure 2 is a partially transparent perspective view of a cylindrical brush of the machine according to the invention, coupled to drive means; Figure 3 is a partially transparent side view of the brush coupled to drive means;

Figure 4 is a cross-sectional view taken along the line IV-IV of Figure 3;

Figure 5 is a cross-sectional view of an attachment element of the machine according to the invention in the step of being coupled with a coupling element that is integral with the brush;

Figure 6 is a partially transparent perspective view of the step of coupling between the attachment element and the coupling element;

Figure 7 is a perspective view of the attachment element of the machine according to the invention;

Figure 8 is a side view of the attachment element;

Figure 9 is another side view of the attachment element;

Figure 10 is an exploded perspective view of the attachment element;

Figure 11 is a perspective view of the coupling element;

Figure 12 is a front elevation view of the coupling element;

Figure 13 is a longitudinal cross-sectional view of the cylindrical brush coupled to the drive means.

With reference to the figures, the floor cleaning machine according to the invention, generally designated by the reference numeral 1 , comprises a chassis 2 that can be moved over the floor.

For example, as in the example shown, the chassis 2 defines a driving seat 2a for the user and is provided with automatic traction means for its movement over the floor. However, the chassis 2 can be of the type that can be entrained by hand by the user.

The chassis 2 supports, in a lower region, at least one cylindrical brush 3 with a substantially horizontal axis, which is operatively connected to drive means 4, supported by the chassis 2, which enable the rotary actuation of the cylindrical brush 3 about its own axis and are preferably constituted by an electric motor. Each cylindrical brush 3 has at least one coupling element 5 which can be detachably engaged by an attachment element 6 connected to the drive means 4.

In particular, such coupling element 5 comprises an annular body 7 which is fixed coaxially to the axis of the cylindrical brush 3 and which axially defines a fastening seat 8 for the attachment element 6.

More specifically, the cylindrical brush 3 can, for example, be provided by a hollow cylindrical body 3a, from the external lateral surface of which bristles 3b protrude substantially radially.

Advantageously, the annular body 7 is axially fixed inside the hollow cylindrical body 3a of the cylindrical brush 3, as shown in the figures, or it can also be fixed to one end of said cylindrical brush.

Conveniently, the fastening seat 8 defined by the annular body 7 is open at at least one axial face 7a of the annular body 7.

The attachment element 6 comprises, in turn, a movement head 9 which can be actuated by the drive means 4 with a rotary motion about a rotation axis 9a.

More specifically, the movement head 9 can be detachably coupled to the fastening seat 8 defined in the annular body 7, via its axial insertion in the fastening seat 8, through the axial face 7a of the annular body 7, in order to allow the rotary entrainment of the cylindrical brush 3 by the movement head 9 about the rotation axis 9a.

According to the invention, the movement head 9 comprises expandable engagement means 10 which are adapted to pass between a retracted position, in which they are brought closer to the rotation axis 9a, in order to allow the insertion of the movement head into the fastening seat 8, and an expanded position, in which they are spaced apart from the rotation axis 9a, in order to allow the expandable engagement means 10 to engage at least one abutment region 11 defined in the annular body 7, for the rotary entrainment of the cylindrical brush 3 by the movement head 9. Advantageously, the expandable engagement means 10 can move between the expanded position and the retracted position in contrast with or by virtue of the action of elastic means 12.

Conveniently, in the annular body 7 there are at least two separate abutment regions 11 which can be engaged selectively by the expandable engagement means 10 according to the direction of rotation of the movement head 9 about the rotation axis 9a, in order to allow the rotary entrainment of the cylindrical brush 3 in one direction or in the other.

In particular, the above two abutment regions 11 are structured so that, with the movement head 9 inserted in the fastening seat 8, one or the other of them can be engaged automatically by the expandable engagement means 10 arranged in the expanded position, once the rotation of the movement head 9 about its own rotation axis 9a has been started by the drive means 4, as will be better explained below.

In more detail, the movement head 9 comprises a central body 13, which can rotate about the rotation axis 9a, and the expandable engagement means 10 comprise, conveniently, at least one engagement tooth 14, which is supported by the central body 13.

In particular, such engagement tooth 14 is integral with the central body 13 in rotation about the rotation axis 9a and can move with respect to the central body 13, in contrast with or by virtue of the action of the elastic means 12, for a variation of its protrusion from the lateral surface of the central body 13.

More specifically, the central body 13 can be inserted into the fastening seat 8 with an insertion end 13a thereof, arranged along the rotation axis 9a, and is, conveniently, connected with the end thereof that lies opposite the insertion end 13a, to the drive means 4.

The engagement tooth 14 extends, advantageously, along a substantially longitudinal extension with respect to the rotation axis 9a of the movement head and, with an end thereof which faces toward the insertion end 13a of the central body 13, is connected to the central body 13 so that it can oscillate about a respective oscillation axis 14a which is substantially perpendicular to a plane that passes through the rotation axis 9a and through the longitudinal axis of the engagement tooth 14.

More specifically, the engagement tooth 14 can oscillate about the respective oscillation axis 14a, so as to be able to pass, in contrast with the elastic means 12, from a coupling position, assumed when the expandable engagement means 10 are in the expanded position, in which the end thereof that is opposite to the end that is oscillatably connected to the central body 13 is spaced apart from the rotation axis 9a, in order to allow its engagement in the abutment regions 11, to an insertion position, assumed when the expandable engagement means 10 are in the retracted position, in which the end thereof that is opposite to the end that is oscillatably connected to the central body 13 is, instead, brought closer to the rotation axis 9a.

It should be noted that, in the coupling position, the face of the engagement tooth 14 that faces away from the rotation axis 9a of the movement head 9 is arranged on a plane that is inclined with respect to the rotation axis 9a and converges toward the rotation axis 9a, proceeding in the direction of the insertion end 13a of the central body 13, in order to facilitate the insertion of the movement head 9 into the fastening seat 8 and enable the automatic transition of the engagement tooth 14 from the coupling position to the insertion position, as a consequence of the engagement tooth 14 sliding against portions of the annular body 7 that are situated around the fastening seat 8, during the insertion of the movement head 9 into the fastening seat 8.

Conveniently, the central body 13 has a substantially axially symmetrical shape with respect to the rotation axis 9a with a lateral surface that extends substantially circumferentially around the rotation axis 9a. In particular, the central body 13 can be, for example, substantially cylindrical or substantially conical or frustum-shaped, with side walls that converge in the direction of its insertion end 13a.

Advantageously, the engagement tooth 14 is accommodated in a respective longitudinally extended groove 15 which is defined in the lateral surface of the central body 13.

Preferably, in the annular body 7 there are, for the engagement tooth 14, at least two distinct abutment regions 11, which can be engaged selectively by the engagement tooth 14 according to the direction of rotation of the movement head 9 about its rotation axis 9a.

Conveniently, each abutment region 11 for the engagement tooth 14 defines, in turn, at least one respective abutment wall 16 arranged on a radial plane with respect to the axis of the annular body 7.

Such abutment wall 16 is designed to be engaged in abutment by at least one portion of the engagement tooth 14 in the coupling position, in order to actuate the rotary entrainment of the annular body 7 by the movement head 9.

Preferably, as in the embodiment shown, the expandable engagement means 10 comprise at least one pair of engagement teeth 14 which are arranged in mutually diametrically opposite positions with respect to the rotation axis 9a of the movement head 9 and, in this case, at least one respective engagement region 11 is conveniently defined in the annular body 7 for each one of the engagement teeth 14.

As illustrated, the elastic means 12 can be constituted, for each engagement tooth 14, by a respective spring 12a, acting between the central body 13 and the relevant engagement tooth 14 in the direction that results in maintaining the relevant engagement tooth 14 in the coupling position.

More preferably, in the annular body 7 there are, for each one of the engagement teeth 14, at least two respective abutment regions 11, each one of which can be engaged selectively by one of the engagements teeth 14 according to the direction of rotation of the movement head 9.

In practice, for each one of the engagement teeth 14, in the annular body 7 there is a first abutment region 11, which is designed to be engaged by the relevant engagement tooth 14, when the movement head 9 is rotated about the rotation axis 9a, in a first direction, for example clockwise, and which is structured so as to allow the rotary entrainment of the annular body 7 and, therefore, of the cylindrical brush 3 in the first direction of rotation, by virtue of its engagement by the relevant engagement tooth 14, and there is a second abutment region 11 , which is engaged, in turn, by the relevant engagement tooth 14, when the movement head 9 is rotated about the rotation axis 9a, in a second direction, opposite to the first direction, for example anticlockwise, and which is structured so as to allow the rotary entrainment of the annular body 7 and, therefore, of the cylindrical brush 3 in the second direction of rotation, by virtue of its engagement by the relevant engagement tooth 14.

Advantageously, the two abutment regions 11 for each engagement tooth 14 have a shape structure that is substantially mutually symmetrical with respect to a radial plane that passes through the axis of the annular body 7.

In more detail, each abutment region 11 comprises, advantageously, a respective accommodation seat 17 for the relevant engagement tooth 14, which is open toward the axis of the annular body 7, in order to allow the entry into it of the relevant engagement tooth 14.

It should be noted that, conveniently, the accommodation seat 17 of each abutment region 11 is open also on the axial face 7a of the annular body 7 at which the movement head 9 is inserted into the fastening seat 8, so as to enable the extraction of the movement head 9 from the fastening seat 8 via the relative movement of the annular body 7 relative to the movement head 9, along the axis of the annular body 7, even with the engagement teeth 14 in the coupling position and in engagement with a respective abutment region 11.

Advantageously, the accommodation seat 17 of each abutment region 11 is delimited radially by a resting surface 18 for the relevant engagement tooth 14 which extends, for at least a part thereof, progressively away from the axis of the annular body 7 proceeding in the direction of rotation about the axis of the annular body 7 that corresponds to the direction of rotation of the movement head 9 that produces the engagement of the corresponding abutment region 11 by the relevant engagement tooth 14.

In particular, the resting surface 18 of each abutment region 11 is slideably engageable by the face of the relevant engagement tooth 14 that faces away from the rotation axis 9a of the movement head 9, in order to allow the progressive transition of the relevant engagement tooth 14 from the insertion position to the coupling position, by virtue of the action of the elastic means 12, upon the rotation of the movement head 9, which is inserted in the fastening seat 8, in the direction of rotation that produces the engagement of the corresponding abutment region 11 by the relevant engagement tooth 14.

Conveniently, the resting surface 18 of each abutment region 11 has, along a direction that is substantially parallel to the axis of the annular body 7, an extension that progressively approaches the axis of the annular body 7, proceeding from the axial face 7a of the annular body 7, at which the movement head 9 is inserted into the fastening seat 8, toward the other axial face 7b of the annular body 7.

Advantageously, the resting surface 18 of the accommodation seat 17 of each abutment region 11 is connected, at the end thereof that faces toward the direction of rotation that produces the engagement of the relevant abutment region 11 by the relevant engagement tooth 14, to the abutment wall 16 of the relevant abutment region 11.

In particular, the abutment wall 16 of each abutment region 11 faces away from the direction of rotation of the movement head 9 that produces the engagement of the corresponding abutment region 11 by the relevant engagement tooth 14. In this way, the abutment wall 16 of each abutment region 11 is engaged by contact by the side flank of the relevant engagement tooth 14 that faces toward the direction of rotation of the movement head 9 that produces the engagement of the corresponding abutment region 11 by the relevant engagement tooth 14, so as to be able to produce the rotary entrainment of the annular body 7 and, consequently, of the cylindrical brush 3 by the movement head 9, following the rotary actuation of the movement head 9 about the rotation axis 9a.

Advantageously, the accommodation seats 17 of the two abutment regions 11 for each engagement tooth 14 are mutually connected by at least one connecting segment 19, which can be slideably engaged by the relevant engagement tooth 14 and which has a shape that is adapted to allow the automatic transition of the relevant engagement tooth 14 from one of the two corresponding abutment regions 11 to the other, as a consequence of the starting of the rotation in one direction or in the other of the movement head 9 about the rotation axis, with the movement head 9 inserted in the fastening seat 8, by virtue of the automatic transition of the relevant engagement tooth 14 from the coupling position to the insertion position, produced by the sliding of the relevant engagement tooth 14 along the connecting segment 19.

In particular, the connecting segment 19 between the abutment regions 11 has, advantageously, a course that extends, proceeding from one to the other of the two abutment regions 11 connected by the connecting segment 19, with a first part progressively closer to the axis of the annular body 7 and a second part, following the first part, progressively away from the axis of the annular body 7.

To ensure the locking in place of the cylindrical brush 3 in an axial direction, once the movement head 9 has been inserted into the fastening seat 8 of the annular body 7, retention means are provided, supported by the chassis 2 of the machine, which are designed to engage the opposite ends of the cylindrical brush 3.

As shown in Figure 13, such retention means comprise, for example, a pair of engaging and centering spigots 20a, 20b, each one rotatably engaging a respective end of the cylindrical brush 3.

Preferably, at least one of the engaging and centering spigots, in particular the one, designated by 20b, that is designed to engage the end of the cylindrical brush 3 toward which the axial face 7b of the annular body 7 faces, is associated with a cover 21, removably connected with the chassis 2, in order to allow, by way of the removal of the cover 21 from the chassis 2, the cylindrical brush 3 to be disengaged from the deploying and centering spigot 20b, so as to enable the operator to extract the cylindrical brush 3 from the chassis 2.

The operation of the machine, according to the invention, is the following.

In order to execute the connection of the cylindrical brush 3 to the drive means 4, the user proceeds to fit the annular body 7 over the movement head 9 with an axial movement, so as to achieve the insertion of the movement head 9 into the fastening seat 8.

If the movement head 9 is in a position at an angle to the annular body 7, in which the engagement teeth 14 have not arrived at the accommodation seats 17 of the abutment regions 11, then the engagement teeth 14, by sliding on portions of the annular body 7 that are located around the fastening seat 8, will be brought from the coupling position to the insertion position in contrast with the elastic means 12, so as to still allow the introduction of the movement head 9 into the fastening seat 8.

At this point, following the activation of the drive means 4 and the consequent starting of the rotation in a direction of the movement head 9 about the rotation axis 9a, the engagement teeth 14, again by sliding on portions of the annular body 7 that are located around the fastening seat 8, by virtue of their rotary entrainment by the movement head 9, can arrive at the abutment regions 11.

If the engagement teeth 14 should meet the abutment regions 11 that are designed to allow the rotation of the annular body 7 in the opposite direction to the direction in which the movement head 9 is rotated, then the engagement teeth 14, still entrained by the rotation of the movement head 9, would slideably engage the resting surface 18 of those abutment regions 11, and would be brought, in contrast with the action of relevant springs 12a, from the coupling position to the insertion position, so as to be able to subsequently clear the connecting segment 19 and so reach the abutment regions 11 that are designed to allow the rotation of the annular body 7 in the same direction as the direction in which the movement head 9 is rotated.

After reaching the abutment regions 11 that allow the rotation of the annular body 7 in the same direction as the direction in which the movement head 9 is rotated, the engagement teeth 14, by sliding on the resting surface 18 of such abutment regions 11, are progressively brought, by the action of the respective springs 12a, from the insertion position to the coupling position, until they engage, with their flank facing in the same direction of rotation as the movement head 16, the abutment wall 16 of those abutment regions 11, so producing the entrainment, by the movement head 9, of the annular body 7 and consequently also of the cylindrical brush 3 in the same direction of rotation as the movement head 9.

In this way, even if the operator were to fit the annular body 7 onto the movement head 9, mistakenly inserting the engagement teeth 7 into a position not corresponding to the positions of the abutment regions 11 designed to allow the rotation of the annular body 7 in the direction corresponding to the direction of rotation of the movement head 9, then the engagement teeth 14 will still be able to automatically arrive, with the start of the rotation of the movement head 9 about the rotation axis 9a, at the correct abutment regions, thus enabling the rotary entrainment of the cylindrical brush 3 in any situation. Let us consider, for example, the case where the operator mistakenly inserts the engagement teeth 14 into the second abutment regions, even though the movement head 9 is designed to be rotated about the rotation axis 9a in the first direction of rotation. In this situation, upon activation of the drive means 4 and the consequent start of the rotation of the movement head 9 in the first direction of rotation, the engagement teeth 14 would be slideably entrained on the resting surface 18 of the second abutment regions and subsequently along the connecting segment 19 until they reach the first abutment regions and their abutment wall 16, so as to produce the rotation of the annular body 7 and, therefore, of the cylindrical brush 3 in the first direction of rotation.

The same is true obviously in the reverse case, i.e. if the operator inserts, by mistake, the engagement teeth 14 into the first abutment regions, instead of the second abutment regions, even though the movement head 9 is designed to be rotated about the rotation axis 9a in the second direction of rotation. In that situation in fact, upon activation of the drive means 4 and the consequent start of the rotation of the movement head 9 in the second direction of rotation, the engagement teeth 14 would be brought into engagement with the second abutment regions, following their sliding on the resting surface 18 of the first abutment regions and along the corresponding connecting segment 19, so as to allow the rotation of the cylindrical brush 3 in the second direction of rotation.

To uncouple the annular body 7 from the movement head 9 it will be sufficient for the operator to slide the annular body out from the movement head 9 with an axial movement of the annular body 7 with respect to the movement head 9 directed in the opposite direction from the direction that allows the insertion of the movement head 9 into the fastening seat 8.

In practice it has been found that the invention fully achieves the intended aim and objects and, in particular, attention is drawn to the fact that, by virtue of its peculiar structuring, the machine according to the invention enables the operator to easily fit the cylindrical brush onto the movement head, independently of the angular position of the cylindrical brush relative to the movement head and to the direction of rotation in which the movement head is rotated.

From the foregoing it can furthermore be seen that another advantage of the invention is that it allows a speed of fastening/unfastening of the cylindrical brushes to/from the drive means that is faster than the solutions currently employed, with a consequent reduction of maintenance times but especially a considerable simplicity of use, even for less expert operators.

The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. Moreover, all the details may be substituted by other, technically equivalent elements.

Thus, for example, the same inventive concept can be used to provide different types of floor cleaning machines, such as for example brushing machines, washing and drying machines, or combined machines.

In practice, the materials used, as well as the contingent shapes and dimensions, may be any according to the requirements and to the state of the art.

The disclosures in Italian Patent Application No. 102022000004082 from which this application claims priority are incorporated herein by reference.

Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. A floor cleaning machine, comprising a chassis (2) which can move on the floor and supports in a lower region at least one cylindrical brush (3) with a substantially horizontal axis which is functionally connected to drive means (4) for the rotary actuation of said cylindrical brush (3) about its own axis, said cylindrical brush (3) having at least one coupling element (5) which can be detachably engaged by an attachment element (6) connected to said drive means (4), said coupling element (5) comprising an annular body (7) which is fixed coaxially to the axis of said cylindrical brush (3) and defines axially a fastening seat (8) for said attachment element (6), said attachment element (6) comprising a movement head (9) which can be actuated by said drive means (4) with a rotary motion about a rotation axis (9a) and can be coupled detachably with said fastening seat (8), for the rotary entrainment of said cylindrical brush (3) by said movement head (9) about said rotation axis (9a), characterized in that said movement head comprises expandable engagement means (10) which are adapted to pass between a retracted position, in which they are brought closer to said rotation axis, in order to allow the insertion of said movement head (9) into said fastening seat (8), and an expanded position, in which they are spaced apart from said rotation axis (9a), in order to allow said expandable engagement means (10) to engage at least one abutment region (11) defined in said annular body (7), for the rotary entrainment of said cylindrical brush (3) by said movement head (9).

2. The machine according to claim 1, characterized in that said expandable engagement means (10) can move between said expanded position and said retracted position, in contrast with or by virtue of the action of elastic means (12).

3. The machine according to claim 1, characterized in that in said annular body (7) there are at least two distinct abutment regions (11) which can be engaged selectively by said expandable engagement means (10) according to the direction of rotation of said movement head (9) about said rotation axis (9a).

4. The machine according to one or more of the preceding claims, characterized in that, with said movement head (9) inserted in said fastening seat (8), one or the other of said at least two abutment regions (11) can be engaged automatically by said expandable engagement means (10) in said expanded position, as a consequence of the starting of the rotation of said movement head (9) about said rotation axis (9a).

5. The machine according to one or more of the preceding claims, characterized in that said movement head (9) comprises a central body (13) which can rotate about said rotation axis (9a), said expandable engagement means (10) comprising at least one engagement tooth (14) which is supported by said central body (13), said at least one engagement tooth (14) being integral with said central body (13) in rotation about said rotation axis (9a) and being movable with respect to said central body (13), in contrast with or by virtue of the action of said elastic means (12), for a variation of its protrusion from the lateral surface of said central body (13).

6. The machine according to one or more of the preceding claims, characterized in that said central body (13) can be inserted in said fastening seat (8) with an insertion end (13 a) thereof arranged along said rotation axis (9a), said at least one engagement tooth (14) having a substantially longitudinal extension with respect to said rotation axis (9a) and being connected, with an end thereof which faces toward said insertion end (13a) of said central body (13), to said central body (13) so that it can oscillate about a respective oscillation axis (14a) which is substantially perpendicular to a plane that passes through said rotation axis (9a) and through the longitudinal axis of said engagement tooth (14).

7. The machine according to one or more of the preceding claims, characterized in that said at least one engagement tooth (14) can oscillate about the respective oscillation axis (14a) in order to pass, in contrast with said elastic means (12), from a coupling position, assumed with said expandable engagement means (10) to said expanded position, in which the end thereof that is opposite to the end that is connected so that it can oscillate to said central body (13) is spaced apart from said rotation axis (9a), in order to allow its engagement in said at least one abutment region (11), to an insertion position, assumed with said expandable engagement means (10) in said retracted position, in which the end thereof that is opposite to the end that is connected so that it can oscillate to said central body (13) is brought closer to said rotation axis (9a).

8. The machine according to one or more of the preceding claims, characterized in that said central body (13) has a substantially axially symmetrical shape with respect to said rotation axis (9a) with a lateral surface that extends substantially circumferentially around said rotation axis (9a).

9. The machine according to one or more of the preceding claims, characterized in that said engagement tooth (14) is accommodated in a respective longitudinal groove (15) defined in the lateral surface of said central body (13).

10. The machine according to one or more of the preceding claims, characterized in that said at least one abutment region (11) defines at least one abutment wall (16) which is arranged on a radial plane with respect to the axis of said annular body (7) and is designed to be engaged in abutment by at least one portion of said at least one engagement tooth (14) in said coupling position, for the rotary entrainment of said annular body (7) by said movement head (9).

11. The machine according to one or more of the preceding claims, characterized in that in said annular body (7) there are, for said at least one engagement tooth (14), at least two distinct abutment regions (11), which can be engaged selectively by said at least one engagement tooth (14) according to the direction of rotation of said movement head (9) about said rotation axis (9a).

12. The machine according to one or more of the preceding claims, characterized in that said expandable engagement means (10) comprise at least one pair of engagement teeth (14) which are arranged in mutually diametrically opposite positions with respect to said rotation axis (9a), at least one respective abutment region (11) being defined in said annular body (7) for each one of said engagement teeth (14).

13. The machine according to one or more of the preceding claims, characterized in that in said annular body (7) there are, for each one of said engagement teeth (14), at least two respective abutment regions (11), each one of which can be engaged selectively by one of said engagements teeth (14) according to the direction of rotation of said movement head (9).

14. The machine according to one or more of the preceding claims, characterized in that the two abutment regions (11) for each engagement tooth (14) have a shape structure that is substantially mutually symmetrical with respect to a radial plane that passes through the axis of said annular body (7).

15. The machine according to one or more of the preceding claims, characterized in that each abutment region (11) comprises a respective accommodation seat (17) for the relevant engagement tooth (14) which is open toward the axis of said annular body (7), the accommodation seat (17) of each abutment region (11) being delimited radially by a resting surface (18) for the relevant engagement tooth (14) which extends, for at least a part thereof, progressively away from the axis of said annular body (7) proceeding in the direction of rotation about the axis of said annular body (7) that corresponds to the direction of rotation of the movement head (9) that produces the engagement of the corresponding abutment region (11) by the relevant engagement tooth (14), said resting surface (18) being slideably engageable by the face of the relevant engagement tooth (14) that faces away from said rotation axis (9a), in order to allow the progressive transition of the relevant engagement tooth (14) from the insertion position to the coupling position, by virtue of the action of said elastic means (12), upon the rotation of said movement head (9), in the direction of rotation that produces the engagement of the corresponding abutment region (11) by the relevant engagement tooth (14), with said movement head (9) inserted in said fastening seat (8).

16. The machine according to one or more of the preceding claims, characterized in that the resting surface (18) of the accommodation seat (17) of each abutment region (11) is connected, at the end thereof that faces toward the direction of rotation that produces the engagement of the corresponding abutment region (11) by the relevant engagement tooth (14), to the abutment wall (16) of the corresponding abutment region (11), the abutment wall (16) of each abutment region (11) facing away from the direction of rotation of said movement head (9) that produces the engagement of the corresponding abutment region (11) by the relevant engagement tooth (14) and being engageable by contact by the side flank of the relevant engagement tooth (14) that faces toward the direction of rotation of said movement head (9) that produces the engagement of the corresponding abutment region (11) by the relevant engagement tooth (14).

17. The machine according to one or more of the preceding claims, characterized in that the accommodation seats (17) of the two abutment regions (11) for each engagement tooth (14) are mutually connected by at least one connecting segment (19) which has a shape that is adapted to allow the automatic transition of the relevant engagement tooth (14) from one of said two abutment regions (11) to the other as a consequence of the starting of the rotation in one direction or in the other of said movement head (9) about said rotation axis (9a), with said movement head (9) inserted in said fastening seat (8).