Clutch assembly, in particular for a winding device for wires, tubes and the like

Abstract

A clutch assembly (10), in particular for a winding device for wires, tubes and the like, which is configured to be mounted between a power group (200) and a driven element (300) is described. The clutch assembly (10) comprises: a first shaft (11) and a second shaft (12) being coaxial and rotational about an axis (X); clutch means (20) interposed between the first and second shafts (11, 12), the clutch means (20) in turn comprising at least one clutch disk (21); an urging and adjusting group (30) for the clutch means (20) configured to press the at least one clutch disk (21) against the first and second shafts (11, 12) with an adjustable elastic force. The urging and adjusting group (30) comprises an endless screw (31) and a gear wheel (32) in mutual screwing engagement.

Description

[0001] Clutch assembly, in particular for a winding device for wires, tubes and the like

[0002] DESCRIPTION

[0003] The present invention relates to a clutch assembly, in particular for a winding device for wires, tubes and the like.

[0004] The patent also relates to a winding device comprising such a clutch assembly.

[0005] Clutch assemblies are known in the state of the art to transmit a torque from a power group, such as a drive element, to a driven element.

[0006] For example, such clutch assemblies are known to be used between an electric motor and a winding device for wires or tubes, either directly or with the interposition of a gearmotor or gearbox. Clutch assemblies can be used when the winding device is intended to wind relatively large masses of cables, as is often the case with winders for marine applications, for example, or in use in workshops or construction sites. The transmitted torque must be adjusted in such a way as to be able to bring high masses into rotation and also to prevent too fast a winding from causing sudden and unpredictable movements of the free end of the wire, or tube or the like, being wound up.

[0007] In addition, torque adjustment also serves to limit tension on the wire, tube, or the like.

[0008] As is known, some clutch assemblies comprise alternating sets of clutch disks that rotate with the drive element and the driven element, while elastic means exert a certain compression on the clutch disk system, depending on the torque to be transmitted.

[0009] Depending on requirements, the required torque is adjusted by screwing on an adjusting ring nut which, when rotated, changes the compression of the elastic means. Such elastic means may consist, for example, of disk springs.

[0010] The elements that make up the clutch assembly are enclosed within a casing, which protects them from external forces and aggressive agents due to the environment in which the winding devices are used, such as in a marine environment.

[0011] Such clutch assemblies have a number of drawbacks, such as the need to open the casing in order to access the adjustment ring nut whenever the need arises to adjust torque loads.

[0012] Another drawback is that such known clutch assemblies have generally high axial dimensions, due to the presence of springs and a multiplicity of components coupled in series along an axis of rotation of the drive element, such as clutch disks and other disks that are pressed together by the adjusting ring.

[0013] A further drawback is that any maintenance that requires changing the clutch elements requires the removal and separation of the elements of a large part of the clutch assembly.

[0014] The task of the present invention is to provide a clutch assembly capable of improving the prior art in one or more of the aspects indicated above.

[0015] As part of this task, an aim of the invention is to create a clutch assembly that allows easy adjustment of the torque to be transmitted to the driven element in order to rewind wires, or tubes or the like, at an appropriate speed.

[0016] Another aim of the invention is to offer a clutch assembly with a smaller axial footprint than known clutch assemblies.

[0017] A further aim of the invention is to offer a clutch assembly that is simpler and easier to maintain than known clutch assemblies.

[0018] A further aim of the invention is to overcome the drawbacks of the prior art in an alternative way to other existing solutions.

[0019] This task and these and other aims are achieved by the present invention by means of a clutch assembly according to the appended claims.

[0020] In a first aspect thereof, the present invention relates to a clutch assembly, in particular for a winding device for wires, tubes and the like and configured to be mounted between a power group and a driven element.

[0021] The clutch assembly comprises:

[0022] - a first shaft configured to be coupled in rotation to a rotating shaft of the power group,

[0023] - a second shaft configured to be coupled in rotation to the driven element,

[0024] - the first and second shaft being coaxial and rotational about an axis,

[0025] - clutch means which are interposed between the first and second shafts and which are configured to couple in rotation the first and second shaft,

[0026] - the clutch means comprising at least one clutch disk,

[0027] - an urging and adjusting group for the clutch means which is configured to press the at least one clutch disk against the first and second shafts with an adjustable elastic force so as to make the torque transmitted between the first and second shafts adjustable. Preferably, the urging and adjusting group comprises:

[0028] - an endless screw and a gear wheel which are in mutual screwing engagement, the gear wheel being configured to rotate about the axis and coaxially about a tubular member by means of a screw / nut connection,

[0029] - the tubular member being constrained to move in translation along the axis following the rotation of the gear wheel.

[0030] Preferably, the urging and adjusting group also comprises a bush which is coaxial to the tubular member, configured to move in translation along the axis with the tubular member towards and away from an elastic element.

[0031] Preferably, the elastic element is active between the bush and the clutch means so that the elastic force is adjustable via the translational movement of the bush. This configuration allows, by means of a rotation imparted to the endless screw, the tubular member and the bush to move in translation away from or towards the elastic element, thus modifying the elastic force so as to adjust the torque.

[0032] Preferably, the urging and adjusting group comprises a bearing arranged, radially with respect to the axis, between the tubular member and the bush, configured to transfer the elastic force to the clutch means and to allow the bush to rotate about the axis together with the second shaft.

[0033] Preferably, the bearing is of the oblique type.

[0034] Preferably the bearing is a rolling bearing, particularly of the ball type.

[0035] Preferably, the bearing is configured to move in translation along the axis with the tubular member and bush.

[0036] Due to one or more of these characteristics, the axial load is transferred directly from the bearing to the bush, which moves in translation towards the elastic element.

[0037] Preferably, the axis corresponds to the axis of rotation of the rotating shaft.

[0038] Therefore, while the tubular member is only constrained to translate along the axis, the bush not only translates with the tubular member, but is also rotationally joined to the second shaft.

[0039] The elastic element is preferably a compression spring.

[0040] Preferably, the elastic element comprises at least one wave spring.

[0041] This wave spring is preferably of the multi-turn type.

[0042] In some embodiments, the elastic element comprises at least one helical spring.

[0043] Due to the fact that the elastic element comprises a spring that works in compression, the elastic force can be adjusted by greater or lesser axial compression of the elastic element by the bush.

[0044] Preferably, the bush directly presses the elastic element.

[0045] Preferably, the clutch assembly is housed in a casing between the power group and the driven element.

[0046] Preferably, the clutch assembly comprises the casing.

[0047] The driven element can be a gearbox.

[0048] The casing protects the clutch assembly components.

[0049] Preferably, the endless screw has a manoeuvring head that can be engaged by a tool.

[0050] Preferably, this manoeuvring head is recessed inside the casing, the casing having an opening for access to the manoeuvring head preferably with a tool.

[0051] It will be appreciated that this conveniently allows access to the urging and adjusting group from the outside and without opening the casing.

[0052] Preferably, the casing has an opening through which a tool, manual or motorised, can be inserted to operate the endless screw.

[0053] Preferably, the opening develops around an axis of rotation of the endless screw. Preferably, the clutch assembly comprises a freewheel installed with an external ring thereof fixedly joined to the casing and with an internal ring thereof fixedly joined to the rotating shaft.

[0054] The expression "with an internal ring thereof fixedly joined to the rotating shaft", referring to the freewheel, means that the internal ring can be directly or indirectly joined to the rotating shaft. In the second case, the internal ring is fixedly joined to an element that is in turn fixedly joined to the rotating shaft. For example, the internal ring can be fixedly joined to an extension tang of the rotating shaft. Preferably, the clutch assembly comprises a rotating shaft extension tang.

[0055] More preferably, the tang is fixedly joined to the rotating shaft by means of a stud that passes through the tang axially and is screwed into the rotating shaft along the axis.

[0056] Preferably, the first shaft is hollow and mounted on an end portion of the tang, the tang and the first shaft are joined in rotation by means of a key interposed between the two.

[0057] The rotating shaft, the tang and the first shaft are thus fixedly joined in rotation.

[0058] The first shaft is free to translate axially with respect to the tang and with respect to the rotating shaft.

[0059] Preferably, the internal ring of the freewheel is fixedly joined to the tang by means of a first key and the external ring is fixedly joined to the casing by means of a second key.

[0060] Thanks to the freewheel, the rotating shaft of the power group is free to rotate in one direction, while rotation of the rotating shaft in the opposite direction is prevented.

[0061] Preferably, the tubular member has guide grooves with which it is constrained to move in translation along the axis on fixed pins.

[0062] Preferably, such pins are fixedly joined to the casing.

[0063] In this way, the rotation of the gear wheel does not cause the rotation of the tubular member, but rather its translation along the axis.

[0064] Preferably, these grooves are formed in the outer wall of the tubular member and run in a direction parallel to the axis.

[0065] Preferably, the tubular member comprises a first portion in the form of an externally threaded sleeve for the screw / nut connection with the gear wheel and in axial succession with respect to the first portion the tubular member also comprises a second portion, which has an annular shape which is diametrically widened with respect to the first portion.

[0066] Preferably, the second portion defines a housing seat for an outer ring of the bearing.

[0067] In some embodiments, the tubular member comprises a first portion, externally threaded for the screw / nut connection with the gear wheel.

[0068] Preferably, the tubular member comprises a second portion that defines a housing seat for an internal ring of the bearing.

[0069] Preferably the second portion is fixedly joined to the first portion.

[0070] Preferably, the bush has a tubular portion and a circular ring developing radially from the wall of the tubular portion which has a greater diameter.

[0071] Preferably, the clutch means comprise an assembly of clutch disks.

[0072] Preferably, the first shaft is provided with at least one flange element.

[0073] Preferably, this flange element is sandwiched between a pair of clutch disks.

[0074] Preferably, the second shaft comprises a bell-like element which defines a housing for the clutch means, the bell-like element having a base, the at least one clutch disk being pressed against the base. Preferably, the clutch means comprise a pressing disk which is coaxial with the first shaft, the pressing disk being configured to press the at least one clutch disk against the base.

[0075] At least two clutch disks are preferably present.

[0076] The base preferably has a discoid shape.

[0077] Preferably, the elastic element is interposed between the circular ring of the bush and the pressing disk.

[0078] Preferably, the bell-like element has arms which develop from the perimeter of the base in a direction parallel with the direction of the axis, the at least one clutch disk and the pressing disk having respective teeth in the region of the perimeter thereof, each of the teeth is retained between a respective pair of arms.

[0079] The clutch and pressing disks have a central opening and coaxial to the first shaft. Preferably, the central opening of the disks is at least partially circular in shape.

[0080] The term "perimeter", referring to the clutch and pressing disks, is intended to refer to the outer contour of these disks and not the inner contour that defines the central opening.

[0081] The disks are constrained in rotation with the bell-like element by means of the arms and teeth.

[0082] Preferably, each of the arms has a retaining portion facing the clutch means.

[0083] Preferably, the clutch means comprise an elastic ring between the retaining portions and the pressing disk.

[0084] Advantageously, the elastic ring retains the pressing disk and clutch disks axially in place.

[0085] In a possible embodiment, the clutch assembly comprises a pair of clutch disks, one disk of the pair of clutch disks being bonded to the base and the other disk of the pair of clutch disks being bonded to the pressing disk.

[0086] In this case, the clutch disks may be without teeth.

[0087] Preferably, there are means of preventing the bush from rotating with respect to the pressing disk.

[0088] The bush and the pressing disk are coaxial, and the bush is partially located, with its tubular portion, inside the central opening of the pressing disk.

[0089] Preferably, the outer wall of the bush has a first flattening and correspondingly the inner wall of the pressing disk has a counter-shaped second flattening.

[0090] The term "outer wall", referring to the bush, means the wall radially furthest from the axis.

[0091] The expression "inner wall", referring to the pressing disk, means the wall radially closest to the axis.

[0092] Preferably, the means preventing the bush from rotating with respect to the pressing disk comprise the first flattening and the second flattening countershaped to the first.

[0093] This feature makes the bush and the pressing disk fixedly joined in rotation.

[0094] It will be appreciated that this ensures that the spring, which is sandwiched between the bush and the pressing disk, is not twisted and thus not damaged by relative rotation between the two elements.

[0095] In some embodiments, the second shaft comprises a base for supporting the clutch means.

[0096] Preferably the clutch means comprise a pressing disk coaxial to the first shaft and configured to press the at least one clutch disk against the base.

[0097] In some embodiments, the pressing disk is mounted in a sliding manner on columns fixedly joined to the base and developing along axes parallel to the axis. Preferably, the clutch means comprise a plate connected to the pressing disk and provided with at least two fins radially projecting outside the at least one clutch disk and defining a support for a portion of the elastic element.

[0098] A winding device for wires, tubes and the like comprises a clutch assembly having at least some of the above characteristics.

[0099] Further features and advantages of the invention will result more from the following description of its preferred, but not exclusive, examples, illustrated, by way of non-limiting example, in the accompanying drawings in which:

[0100] - Figure 1 shows a longitudinal section of a clutch assembly according to the invention mounted between a power group and a driven element;

[0101] - Figure 2 is an enlargement of the clutch assembly as shown in Figure 1;

[0102] - Figures 3 and 4 show further longitudinal sections of the clutch assembly in Figure 1;

[0103] - Figure 5 shows a cross-section of the clutch assembly according to the invention;

[0104] - Figure 6 shows the urging and adjusting group in a perspective view and partially in section;

[0105] - Figure 7 shows a part of the clutch assembly in a perspective view and partially in section;

[0106] - Figure 8 shows a part of the clutch assembly in a perspective and sectional view;

[0107] - Figure 9 shows a winding device with a clutch assembly according to the invention;

[0108] - Figure 10 shows another embodiment of the clutch assembly according to the invention, in a perspective view and partially in section;

[0109] - Figure 11 shows a longitudinal section of the clutch assembly in Figure 10;

[0110] - Figure 12 shows a part of the clutch assembly in Figure 10, with elements for coupling to the power group, in a perspective view and partially in section;

[0111] - Figure 13 shows a part of the clutch assembly in Figure 10, in a perspective view.

[0112] With reference to the above-mentioned figures, the clutch assembly, which is designed especially for winding devices for wires, tubes and the like, is indicated overall with 10 and is mounted between a power group 200 and a driven element 300. In the examples shown, the driven element 300 is a gearbox.

[0113] Figure 9 shows a winding device 100 comprising a clutch assembly 10. Although not illustrated, a clutch assembly 410, which is another example of an embodiment of the invention, can be used as an alternative to the clutch assembly 10 in the winding device 100. The winding device 100 comprises a support frame 110 and a drum 120 onto which a cable 130 is wound.

[0114] The clutch assembly 10 comprises:

[0115] - a first shaft 11 configured to be coupled in rotation to a rotating shaft 211 of the power group 200,

[0116] - a second shaft 12 configured to be coupled in rotation to the driven element 300,

[0117] - the first and second shafts 11, 12 being coaxial and rotating about an axis X,

[0118] - clutch means 20 which are interposed between the first and second shafts 11, 12 and which are configured to couple in rotation the first and second shaft 11, 12.

[0119] The first and second shafts 11, 12 are coaxial to the rotating shaft 211, the axis X corresponds to the axis of rotation of the rotating shaft 211.

[0120] The clutch means 20 comprise at least one clutch disk 21. There may be an assembly of clutch disks, and in the case illustrated there are two clutch disks 21. The clutch assembly 10 conveniently also comprises an urging and adjusting group 30 for the clutch means 20 which is configured to press the clutch disks 21 against the first and second shafts 11, 12 with an adjustable elastic force, so as to make the torque transmitted between the first and second shafts 11, 12 adjustable. Figure 6 illustrates the urging and adjusting group 30.

[0121] The urging and adjusting group 30 comprises an endless screw 31 and a gear wheel 32 which are in mutual screwing engagement, the gear wheel 32 being configured to rotate about the axis X and coaxially about a tubular member 33 by means of a screw / nut connection.

[0122] The tubular member 33 is constrained to move in translation along the axis X following the rotation of the gear wheel 32.

[0123] Preferably, the urging and adjusting group 30 also comprises a bush 34 which is coaxial to the tubular member 33, configured to move in translation along the axis X with the tubular member 33 towards and away from an elastic element 35.

[0124] Preferably, the elastic element 35 is active between the bush 34 and the clutch means 20 so that the elastic force is adjustable via the translational movement of the bush 34.

[0125] The urging and adjusting group 30 comprises a bearing 36 arranged, radially with respect to the axis X, between the tubular member 33 and the bush 34, configured to transfer the elastic force to the clutch means 20 and to allow the bush 34 to rotate about the axis X together with the second shaft 12.

[0126] Preferably, the bearing 36 is of the oblique type. Even more preferably rolling and in particular of the ball type.

[0127] Preferably, the bearing 36 is configured to translate along the axis with tubular member 33 and bush 34.

[0128] The elastic element 35 illustrated is a wave spring of the multi-turn type.

[0129] The bush 34 directly presses the elastic element 35.

[0130] Furthermore, while the tubular member 33 is only constrained to translate, the bush 34, in addition to translating with the tubular member, rotates together with the second shaft 12.

[0131] The clutch assembly 10 is housed in a casing 40 between the power group 200 and the driven element 300.

[0132] The endless screw 31 has a manoeuvring head 31a which can be engaged by a tool. Said manoeuvring head 31a is recessed inside the casing 40, which suitably has an opening 41 for access to the manoeuvring head 31a preferably with a tool.

[0133] The opening 41 is shown in Figure 5. From the opening 41, a tool can be inserted, either manually or motorised, to operate the endless screw 31. This opening 41 develops around an axis of rotation Y of the endless screw 31.

[0134] The clutch assembly 10 comprises a freewheel 50 installed with an external ring thereof fixedly joined to the casing 40 and with an internal ring thereof fixedly joined to the rotating shaft 211. The freewheel 50 is illustrated in a simplified manner and the two rings are not visible.

[0135] The freewheel 50 is installed in a housing 51 fixedly joined to the casing 40 by means of screws 52.

[0136] An elastic ring 53 creates an axial constraint for the freewheel 50 inside the housing 51.

[0137] The clutch assembly comprises an extension tang 211 of the rotating shaft 212.

[0138] The tang 212 is fixedly joined to the rotating shaft 211 by means of a stud lib which passes through the tang 212 axially and is screwed into the rotating shaft 211 along the axis X.

[0139] The first shaft 11 is hollow and is mounted on an end portion of the tang 212; the tang 212 and first shaft 11 are joined in rotation by means of a key 11c interposed between the two. The key 11c is visible in the view in Figure 3. For proper functioning, the first shaft 11 must be free to translate axially with respect to the tang 212.

[0140] An additional key lid is present between the tang 212 and the rotating shaft 211. The key fixedly joins the two components together. This key is visible in the view in Figure 2.

[0141] The internal ring of the freewheel 50 is fixedly joined to the tang 212 by means of a first key 50a and the external ring is fixedly joined to the casing 40 by means of a second key 50b. More specifically, the external ring is fixedly joined to the housing 51 and the internal ring, being fixedly joined to the tang 212, is also fixedly joined to the rotating shaft 211, at least insofar as the tang is fixedly joined to the rotating shaft.

[0142] The freewheel 50 is configured to allow free rotation of the rotating shaft 211 of the power group in one direction and to prevent rotation of the same shaft in the opposite direction. Preferably, the rotation direction allowed corresponds to the winding direction of the wire or tube or the like, and therefore in this condition the rotational motion is transmitted to the driven shaft.

[0143] Figure 4 and Figure 6 show how the tubular member 33 has guide grooves 33a with which it is constrained to move in translation along the axis X on fixed pins 42. These pins 42 are fixedly joined to the casing 40 and the grooves 33a are formed in the outer wall of the tubular member 33 and run in a direction parallel to the axis X.

[0144] The pins 42 are thus engaged with the grooves 33a of the tubular member 33.

[0145] In detail, the tubular member 33 comprises a first portion 33' in the form of an externally threaded sleeve for the screw / nut connection with the gear wheel 32, and in axial succession with respect to the first portion 33' the tubular member 33 also comprises a second portion 33", which has an annular shape which is diametrically widened with respect to the first portion 33'.

[0146] The second portion 33" defines a housing seat for an outer ring of the bearing 36. The first portion 33' and the second portion 33" are two separate pieces joined together by screws 33b, which are visible in the section in Figure 4.

[0147] The grooves 33a are formed on the second portion 33".

[0148] The bush 34 has a tubular portion 34' and a circular ring 34", developing radially from the wall of the tubular portion 34' which has a greater diameter.

[0149] The internal ring of the bearing 36 rests on the circular ring 34" and can rotate fixedly joined to the circular ring 34".

[0150] The internal ring is housed in the space defined between the tubular portion 34' and the circular ring 34".

[0151] Reference is now made to the figures showing the longitudinal sections and also to the perspective view in Figure 7.

[0152] The first shaft 11 is provided with at least one flange element 11'.

[0153] This flange element 11' is sandwiched between a pair of clutch disks 21. The flange element 11' features an annular groove 11", which by increasing the heat exchange surface helps to expel heat due to friction with the clutch disks 21.

[0154] The second shaft 12 comprises a bell-like element 22 defining a housing for the clutch means 20. The bell-like element 22 has a base 23 against which the clutch disks 21 are pressed.

[0155] The clutch means 20 comprise a pressing disk 24 coaxial to the first shaft 11. The pressing disk 24 is configured to press the clutch disks 21 against the base 23. The base 23 has a discoid shape. The pressing disk 24 and clutch disks 21 have a respective opening central and coaxial to the first shaft 11. The opening of the clutch disks is circular, while the opening of the pressing disk is partially so, due to the presence of a flattening described below.

[0156] The elastic element 35 is interposed between the circular ring 34" and the pressing disk 24, as shown in the longitudinal section views and in Figure 8.

[0157] The bell-like element 22 has arms 25 which develop from the perimeter of the base 23 in a direction parallel to the direction of the axis X. The clutch disks 21 and the pressing disk 24 have respective teeth 21' and 24' in the region of the perimeter and each of the teeth is retained between a respective pair of arms. Each of the arms 25 has a retaining portion 26 facing the clutch means 20.

[0158] This configuration, with arms 25 and teeth, rotationally constrains the disks with the bell-like element 22.

[0159] The clutch means 20 comprise an elastic ring 27, between the retaining portions 26 and the pressing disk 24.

[0160] The elastic ring 27, e.g. a seeger, retains the pressing disk 24 and clutch disks 21 axially in place.

[0161] In a possible variant, the disks of the pair of clutch disks 21 are bonded to the base 23 and the pressing disk 24, respectively. In this case, the disks may be without teeth.

[0162] The bush 34 and the pressing disk 24 are coaxial and the bush 34 is partially located, with its tubular portion, inside the central opening of the pressing disk 24. Figure 8 shows the bush 34 and the pressing disk 24 in a perspective view from which it can be seen that the outer wall of bush 34 has a first flattening 34a and correspondingly the inner wall of the pressing disk 24 has a second flattening 24a. In this way, the bush 34 is constrained to rotate with the pressing disk 24 and the spring interposed between them is not twisted, because it rotates fixedly joined to the bush and the pressing disk.

[0163] The clutch assembly 10 is hermetically sealed due to the presence of gaskets in the upper and lower faces connecting the casing to the power group and the driven element, each member communicating with the outside is protected by O-rings.

[0164] The casing 40 is coupled to the power group 200 and the driven element 300 with screws 43.

[0165] A winding device for wires, tubes and the like, which is illustrated schematically in Figure 9, comprises a clutch assembly 10 of the type described above.

[0166] A further example of the clutch assembly according to the invention is shown in Figures 10 to 13 and indicated overall with 410.

[0167] Parts equivalent to those in the previous example are marked by the same numerical references and will not be described again below.

[0168] Some equivalent details not visible in Figures 10-13 (such as the opening 41 for access to the manoeuvring head, the elastic ring 53 and the second key 50b), have already been described and shown for the previous example. For better understanding, reference is to be made to what has been explained and described above.

[0169] In this example, the elastic element 435 is preferably a helical spring.

[0170] In addition, there is a bush 460, which is a fixed part of the clutch assembly 410, i.e. fixed with respect to the casing 40. The bush 460 has at least one groove 460a, on its inner surface, guiding the translation of the tubular member 433 in the direction of the axis X. The groove 460a runs in the direction of the axis X.

[0171] The tubular member 433 is provided with at least one key 433a with which it is constrained to translate in a respective groove 460a of the bush 460. Preferably, the tubular member 433 has a pair of keys 433a arranged in diametrically opposite positions, as visible in the sectional view shown in Figure 11.

[0172] The bush 460 has a raised end-stop 460b for each key 433a. In particular, this raised part 460b is preferably defined by a ring, more preferably an elastic ring, which is mounted in an annular groove formed in the outer surface of the bush 460 and which intercepts the grooves 460a. The raised part prevents the tubular member from descending beyond a certain height, preventing the spring from being overcompressed.

[0173] It should be noted that in this example the constraints on the translation of the tubular member are housed within the clutch assembly and independently of the casing, facilitating assembly and maintenance operations.

[0174] The tubular member 433 comprises first portion 433' externally threaded for the screw-nut connection with the gear wheel 32 and a second portion 433" defining a housing seat for an inner ring of the bearing 436.

[0175] The second portion is fixedly joined to the first portion, being preferably joined to it by screws, and is arranged substantially axially to the first portion.

[0176] Similar to the previous example, the bush, here indicated by reference number 434, has a tubular portion 434' and a circular ring 434", developing radially from the wall of the tubular portion 434' which has a greater diameter. In the example shown, the circular ring develops radially outwards at the top of the tubular portion. Essentially, the circular ring with the outer wall of the tubular portion creates a circular seat for supporting the end coil of the helical spring.

[0177] In addition, the bush 434 has a seat in its radially innermost part for the outer ring of the bearing 436. This seat has two circular raised parts between which the outer ring is placed, preferably defined by the conformation of the body of the bush 434 and an elastic ring, respectively.

[0178] As in the previous example, the first shaft 11 is provided with a flange element 11' which is sandwiched between a pair of clutch disks 21.

[0179] The second shaft 12 comprises a base 23 for supporting the clutch means 20. The clutch means 20 comprise a pressing disk 24 coaxial to the first shaft 11 and this pressing disk 24 is configured to press the clutch disks 21 against the base 23. The flange element 11' with the clutch disks 21 are sandwiched between the pressing disk 24 and the base 23.

[0180] The base 23 is discoid shaped, while the pressing disk 24 and clutch disks 21 have a respective central opening and are coaxial to the first shaft 11.

[0181] The pressing disk 24 is mounted in a sliding manner on columns 428 fixedly joined to the base 23 and running along axes parallel to the axis X. The columns 428 keep the pressing disk 24 (coaxial to the first shaft) centred and guide its sliding. The columns 428, by way of example six in the illustrations, are preferably arranged circumferentially around the axis X and are equidistant from each other. In some cases the disks of the pair of clutch disks can be bonded to the base 23 and the pressing disk 24 respectively.

[0182] The clutch means 20 comprise a plate 429 connected to the pressing disk 24 and provided with fins 429' which project radially outward from the clutch disks 21 and define a support for a portion of the elastic element, i.e. a coil of the helical spring. The plate has an annular-shaped main portion, coaxial to the pressing disk and the first shaft, and the fins project from the main portion and are preferably present in pairs in diametrically opposite positions. The plate is connected to the pressing disk at the face of the latter which is opposite the face facing the clutch disks. The plate 429 is preferably fixedly joined to the pressing disk 24 by means of screws 429". The support defined by the fins 429' is radially external to the clutch means 20 with respect to the axis X. The fins 429' are preferably bent in an "S" shape so as to provide a stable support for the elastic element 435. Since the plate 429 is fixedly joined to the pressing disk 24, essentially the elastic element 435 is axially interposed between the circular ring 434" of the bush 434 and the pressing disk 24, indirectly exerting a thrust on the pressing disk 24. The arrangement of the elastic element 435 radially outward from the clutch disks means that the heat generated by the friction of the disks only reaches the elastic element through the contact points on the fins. The elastic element is less affected by heat than other configurations and, therefore, its performance remains unchanged.

[0183] The pressing disk 24 with the plate 429 can translate in the direction X on the columns 428 depending on the force exerted by the elastic element. The columns 428 each have a circular groove that accommodates an elastic ring 427 on the radially outer side with respect to the axis X. The elastic ring, for example a seeger, axially retains the clutch means 20.

[0184] The operation of the clutch assembly, according to the invention, is as follows. Through the opening 41, it is possible to access the endless screw manoeuvring head 31 with a tool, in order to operate the urging and adjusting group 30.

[0185] By rotating the endless screw 31 along axis of rotation Y, the gear wheel 32 is rotated about the axis X causing the tubular member 33 to move with the grooves 33a on the pins 42.

[0186] The translation of the tubular member 33 causes the translation of the bearing 36, whose outer ring is housed in the seat defined by the second portion 33" of the tubular member. The internal ring rests on the circular ring 34" and since the bearing is interposed between the tubular member 33 and the bush 34, the latter is also moved in translation.

[0187] In the second example described, the rotating action on the endless screw causes the tubular member 433 to translate in the same way, in this case with the keys 433a in the grooves 460a. The translation of the tubular member 433 in turn causes the translation of the bearing 436, whose inner ring is positioned at the housing seat defined in the second portion of the tubular member 433. The outer ring of the bearing is positioned in the defined seat of the bush 434. In this case too, the translation is transmitted to the bush 434.

[0188] A rotation direction imparted to the endless screw 31 corresponds to a translation direction of the tubular member 33, 433 and thus of the bush 34, 434.

[0189] If the translation is directed towards the elastic element 35, 435, the adjustment increases the compression of the elastic element. In particular, the axial load is transferred from the bearing 36, 436 to the bush 34, 434 and the bush 34, 434 directly presses the elastic element 35, 435. Since it is a wave spring, which therefore works in compression, the elastic element is compressed more and therefore exerts greater pressure against the pressing disk 24. The same happens with the helical spring, which, working in compression, exerts a thrust force on the fins 429', and thus against the pressing disk 24. The clutch disks 21 are pushed harder against the base 23, increasing the torque that can be transmitted between the first and second shafts 11 and 12.

[0190] In this condition, the clutch means are active.

[0191] During the winding of a wire, or tube or the like, with the power group active, the first shaft 11 is brought into rotation by connection with the rotating shaft 211. The first shaft 11 rotates at the speed of the rotating shaft and fixedly joined to it. The flange element 11' is then also brought into rotation, and as a result, the clutch means 20 can creep at the interface surfaces between the clutch disks 21 and the flange element 11'. The rotation is then transferred to the second shaft 12.

[0192] The rotation of the second shaft 12 implies the rotation, fixedly joined to it, of the clutch disks 21, the pressing disk 24 (with possible plate 429 fixedly joined to the pressing disk) and with this also the elastic element 35, 435 and the bush 34, 434. If an external force is applied to the tube and thus to the winder, such as a force that holds the tube against the winding, creep occurs and the second shaft 12 rotates at a lower speed than the first shaft 11.

[0193] If no external force is applied, the two shafts rotate together at the same speed and creep does not occur.

[0194] The bearing 36, 436 allows rotation of the bush 34, 434 with respect to the tubular member 33, 433.

[0195] At the top, with respect to the drawings illustrating the clutch assembly according to the invention, is the aforementioned freewheel 50.

[0196] During winding, the freewheel 50 allows the rotating shaft 211 to rotate.

[0197] The freewheel 50 prevents the rotating shaft 211 from rotating in the opposite direction, which corresponds to the unwinding direction of the cable. Therefore, when the power group is not active, accidental unwinding of the cable (e.g. caused by oscillations or vibrations of the utility in which the winder is installed), which would cause rotation of the first shaft and thus the rotating shaft, is prevented. Basically, oscillations and vibrations would cause the drum on which the cable is wound to rotate in the unwinding direction, and thus the second shaft connected thereto. This rotation would be transmitted to the first shaft via the clutch means connecting it to the second shaft, until it reaches the rotating shaft. The freewheel prevents this rotation.

[0198] In order to unwind the tube, the user must overcome the friction force due to the clutch assembly. In this case, the second shaft 12, fixedly joined to the clutch disks, the pressing disk, elastic element and bush, rotates at a speed that depends on the speed at which the cable is pulled out.

[0199] It should also be noted that in the event of maintenance to the clutch means, it is sufficient to unscrew the screws 43 with which the casing 40 is coupled to the power group 200 and the driven element 300 and to remove the group of elements consisting of: shafts, first 11 and second 12, clutch disks 21, pressing disk 24 and elastic ring 27, 427. In the case of the clutch assembly 410, other components such as columns 428 and plate 429 are also included in the group of elements, which are to be removed for maintenance of the clutch means. The elastic element 35 can also be easily removed and replaced if necessary.

[0200] In practice, it was found that the invention achieves its task and purpose by producing a clutch assembly that allows easy adjustment of the torque to be transmitted to the driven element, simply by acting from outside the casing on the endless screw and without having to open the casing to access the internal components.

[0201] Furthermore, the clutch assembly's footprint is smaller than those known to date, due to the fact that some components of the urging and adjusting group are not mounted in succession, but rather at least partially inside each other and coaxially. In fact, thanks to the screw-nut connection, the translation of the tubular member takes place partially inside the gear wheel and the latter does not move axially due to the rotation imparted by the endless screw. In addition, the bush is mounted at least partially inside the tubular member, further containing the overall dimensions.

[0202] Therefore, an externally induced adjustment, acting on the endless screw, and a configuration with coaxial elements that can be moved, at least partially, one inside the other, makes it possible to significantly reduce the footprint of the clutch assembly.

[0203] It is also noteworthy that the grouping of the clutch means in the bell-like element allows for easy maintenance of the clutch assembly, as well as contributing to the clutch assembly's small footprint.

[0204] Again, it should be noted that the presence of the freewheel allows greater control over the winder. By preventing the rotating shaft from rotating in the opposite direction to the winding direction, accidental unwinding of the cable is prevented. The invention is susceptible to many modifications and variants, all falling within the same inventive concept.

Claims

CLAIMS1. A clutch assembly (10, 410), in particular for a winding device for wires, tubes and the like, which is configured to be mounted between a power group (200) and a driven element (300), the clutch assembly (10, 410) comprising:- a first shaft (11) configured to be coupled in rotation to a rotating shaft (211) of the power group (200),- a second shaft (12) configured to be coupled in rotation to the driven element (300),- the first and second shafts (11, 12) being coaxial and rotational about an axis (X),- clutch means (20) which are interposed between the first and second shafts (11, 12) and which are configured to couple in rotation the first and second shaft (11, 12),- the clutch means (20) comprising at least one clutch disk (21),- an urging and adjusting group (30) for the clutch means (20) which is configured to press the at least one clutch disk (21) against the first and second shafts (11, 12) with an adjustable elastic force so as to make the torque transmitted between the first and second shafts (11, 12) adjustable,- the urging and adjusting group (30) comprising:- an endless screw (31) and a gear wheel (32) which are in mutual screwing engagement, the gear wheel (32) being configured to rotate about the axis (X) and coaxially about a tubular member (33, 433) by means of a screw / nut connection,- the tubular member (33, 433) being constrained to move in translation along the axis (X) following the rotation of the gear wheel (32),- a bush (34, 434) which is coaxial with the tubular member (33, 433) and which is configured to move in translation along the axis (X) with the tubular member (33, 433) towards and away from an elastic element (35, 435),- the elastic element (35, 435) being active between the bush (34, 434) and the clutch means (20) so that the elastic force is adjustable via the translational movement of the bush (34, 434),- a bearing (36, 436) which is arranged, radially with respect to the axis (X), between the tubular member (33, 433) and the bush (34, 434) and whichis configured to transfer the elastic force to the clutch means (20) and to allow the rotation of the bush (34, 434) about the axis (X) together with the second shaft (12).

2. A clutch assembly (10, 410) according to claim 1, wherein the bearing (36, 436) is configured to move in translation along the axis (X) with the tubular member (33, 433) and with the bush (34, 434).

3. A clutch assembly (10, 410) according to one or more of the preceding claims, which is housed in a casing (40) between the power group (200) and the driven element (300).

4. A clutch assembly (10, 410) according to claim 3, which comprises a freewheel (50) which is installed with an external ring thereof fixedly joined to the casing (40) and with an internal ring thereof fixedly joined to the rotating shaft (211).

5. A clutch assembly (10, 410) according to one or more of the preceding claims, wherein the endless screw (31) has a manoeuvring head (31a) which can be engaged by a tool.

6. A clutch assembly (10) according to one or more of the preceding claims, wherein the elastic element (35) comprises at least one wave spring.

7. A clutch assembly (10) according to one or more of the preceding claims, wherein the tubular member (33) has guide grooves (33a) with which it is constrained to move in translation along the axis (X) on fixed pins (42).

8. A clutch assembly (10) according to one or more of the preceding claims, wherein the tubular member (33) comprises a first portion (33') in the form of an externally threaded sleeve for the screw / nut connection with the gear wheel (32) and in axial succession with respect to the first portion (33') the tubular member (33) also comprises a second portion (33") which has an annular shape which is diametrically widened with respect to the first portion (33').

9. A clutch assembly (10) according to one or more of the preceding claims, wherein the bush (34) has a tubular portion (34') and a circular ring (34") developing radially from the wall of the tubular portion (34') which has a greater diameter.

10. A clutch assembly (10) according to one or more of the preceding claims, wherein the first shaft (11) is provided with at least one flanged element (11') which is closed in a sandwich-like manner between a pair of clutch disks (21).

11. A clutch assembly (10) according to one or more of the preceding claims,wherein the second shaft (12) comprises a bell-like element (22) which defines a housing for the clutch means (20), the bell-like element (22) having a base (23), the at least one clutch disk (21) being pressed against the base (23).

12. A clutch assembly (10) according to claim 11, wherein the clutch means (20) comprise a pressing disk (24) which is coaxial with the first shaft (11), the pressing disk (24) being configured to press the at least one clutch disk (21) against the base (23).

13. A clutch assembly (10) according to claims 9 and 12, wherein the elastic element (35) is interposed between the circular ring (34") of the bush (34) and the pressing disk (24).

14. A clutch assembly (10) according to claim 12 or 13, wherein the bell-like element (22) has arms (25) which develop from the perimeter of the base (23) in a direction parallel with the direction of the axis (X), the at least one clutch disk (21) and the pressing disk (24) having respective teeth (21', 24') in the region of the perimeter thereof, each of the teeth is retained between a respective pair of arms (25).

15. A clutch assembly (10) according to one or more of claims 12 to 14, which comprises a pair of clutch disks (21), one disk of the pair of clutch disks (21) being bonded to the base (23) and the other disk of the pair of clutch disks (21) being bonded to the pressing disk (24).

16. A clutch assembly (410) according to claim 1, wherein the second shaft (12) comprises a base (23) for supporting the clutch means (20) and the clutch means (20) comprise a pressing disk (24) coaxial to the first shaft (11) and configured to press the at least one clutch disk (21) against the base (23).

17. A clutch assembly (410), according to the preceding claim, wherein the pressing disk (24) is mounted in a sliding manner on columns (428) fixedly joined to the base (23) and developing along axes parallel to the axis (X).

18. A clutch assembly (410), according to claim 16 or 17, wherein the clutch means (20) comprise a plate (429) connected to the pressing disk (24) and provided with at least two fins (429') radially projecting outside the at least one clutch disk (21) and defining a support for a portion of the elastic element (435).

19. A clutch assembly (410), according to claim 1, wherein the tubular member (433) comprises a first portion (433') externally threaded for the screw-nut connection with the gear wheel (32) and a second portion (433") defining ahousing seat for an internal ring of the bearing (36, 436).

20. A winding device for wires, tubes and the like, which comprises a clutch assembly (10, 410) according to one or more of the preceding claims.

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