REEL-BASED TIGHTENING DEVICE

Abstract

 The present invention relates to a reel-based tightening device (1, 1') adapted to be applied to an article provided with a pair of flaps to be moved towards/away from one another. The device (1, 1') comprises a spool (3) capable of rotating around a rotation axis (X-X) and a actuating member (4, 4'), which can operatively be connected to said spool (3) and can be operated by a user to cause said spool (3) to rotate around said rotation axis (X-X) so as to wind at least a portion of a traction element (100) thereon. Furthermore, the device (1, 1') comprises a first transmission unit (6) comprising a first set of component elements, adapted to cooperate with said actuating control member (4, 4') in a first operating condition to drive said spool (3) in rotation with a first gear ratio (R1), a second transmission unit (7) comprising a second set of component elements, adapted to cooperate with said actuating member (4, 4') in a second operating condition to drive said spool 3 in rotation with a second gear ratio (R2), which is different from the first gear ratio (R1), and a switching unit (200) configured to switch the transmission between said actuating member (4, 4') and said spool (3) during the winding of said at least one traction element (100) from said first gear ratio (R1) to said second gear ratio (R2) upon exceeding a predetermined threshold value of the tension of said traction element (100).

Description

TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to a reel-based tightening device adapted to be applied to articles of various kinds, in particular - but not exclusively - sports articles, such as sports footwear, for example ski boots or hiking boots or cycling shoes, backpacks, clothing, protective helmets or medical articles such as orthopaedic braces. In general, a reel-based tightening device according to the present invention finds application where there is a need to move a pair of flaps towards/away from each other by winding and releasing at least one traction element, such as for example a cable or a rope.

BACKGROUND OF THE INVENTION

[0002] Reel-based tightening devices that enable the releasable tensioning of a traction cable have long been known and used to obtain the controlled tightening of a pair of flaps, whether they belong to sports footwear or to other articles.

[0003] These devices substantially comprise a spool and at least one traction element, such as a cable. The spool is generally associated with one of the two flaps to be moved towards one another, or optionally with an element interposed between them, said traction element being able to be constrained - with at least one first end - to said spool and being able to the associated - with a second end and/or with at least one intermediate portion - with a second flap of said pair of flaps, developing between them along a tightening path.

[0004] The spool is capable of rotating around a rotation axis, which generally is essentially perpendicular to the surface of the flap with which it is associated, and is operatively connected to an actuating member, such as, for example, a knob, by means of which the user can cause it to rotate in order to wind/unwind the traction element around it.

[0005] Specifically, by rotating the knob of the reel-based tightening device in a first rotation direction to wind the cable on the spool, the flaps progressively move closer to one another, until the desired tightening of the flaps is achieved, conversely, by rotating the knob of the reel-based tightening device in a second rotation direction, the release of the cable and, therefore, a progressive reduction of the tightening force acting on the flaps are obtained.

[0006] These devices are particularly appreciated by users, in particular in the sports footwear industry, as they allow the tightness of the footwear around the foot to be precisely adjusted, hence increasing the comfort perceived by the user.

[0007] Sometimes, these tightening devices are equipped with appropriate reduction gears, interposed between the knob and the spool, adapted to reduce the effort that the user must apply in order to obtain the desired tightening force.

[0008] A drawback that is observed in the use of a reel-based tightening device equipped with an effort reduction gear lies in the fact that, in case it is used for tightening a rather rigid sports footwear, such as for example a ski boot, in order to allow the user's foot to be inserted and extracted, the amount of cable that must be unwound from the spool to obtain a suitable parting of the flaps is quite high; this entails an aggravation of the amount of time subsequently required of the user to take up the cable and obtain the tightening of the footwear again.

[0009] In fact, the greater the reduction in the effort allowed by the reduction gear incorporated in the reel device, the greater the number of revolutions that the user must perform on the knob to take up the cable and achieve the desired tightening force.

[0010] Document US11730238 shows a reel device for tensioning a cable, which comprises a shift assembly configured to automatically change the drive ratio as a function of a detected torque force. In this document, the switching between a first configuration (high speed) and a second configuration (with mechanical advantage) takes place when a given threshold rotational force is exceeded, which requires the axial lifting of a shift member through the engagement between ramp profiles. As a consequence, the reel device requires an additional inner volume to permit the vertical travel of the component in order to allow for the switching of the transmission configuration.

[0011] Furthermore, in the solution shown in US11730238, the full release of the cable requires an axial movement of the knob, thus further increasing the vertical dimensions of the device.

SUMMARY OF THE INVENTION

[0012] The main task of the subject-matter of the present invention is to overcome the drawbacks of the prior art mentioned above by providing a reel-based tightening device adapted to be applied to an article provided with a pair of flaps to be mutually moved towards, said reel-based tightening device allowing for a reduction in the amount of time needed to take up the traction element, however requiring a limited effort to achieve the precise tightening desired.

[0013] Within the scope of the present task, an object of the invention is to provide a reel-based tightening device that is practical and easy to operate.

[0014] A further object of the present invention is to provide a reel-based tightening device that also allows for a quick release of the traction element.

[0015] Another object of the present invention is to provide a reel-based tightening device that also permits the controlled release of the traction element, so as to enable the fine adjustment of the tightening of the flaps.

[0016] Finally, another object of the present invention is to obtain a compact reel-based tightening device provided with a lowered profile, so that it can be applied for the tightening of sports footwear.

[0017] Last but not least, an object of the present invention is to devise a reel-based tightening device that can be obtained through the use of easily available means and components, so that it can be manufactured with usual and known plants, machinery and equipment.

[0018] The task, objects and advantages indicated above, as well as others that will better appear in the description that follows, are achieved by a reel-based tightening device as defined in claim 1. Further advantageous features of a reel-based tightening device according to the present invention are contained in the following dependent claims.

BRIEF DESCRIPTION OF THE FIGURES

[0019] Advantages and characteristics of a reel-based tightening device according to the present invention will be better explained in the description of particular, but not exclusive embodiments shown by way of non-limiting example in the accompanying drawings, wherein:

• FIGGS. 1A, 1B show, with exploded views according to different angles, a reel-based tightening device according to a first embodiment of the present invention;
• FIG. 2A shows, with an exploded view, the components defining the first transmission unit, engaged to transmit the rotation in a first operating condition;
• FIG. 2B shows, with an exploded view, the components defining the second transmission unit, engaged to transmit the rotation in a second operating condition;
• FIG. 3 shows, with an isometric view, the inner face of the actuating member of the reel-based tightening device according to the first embodiment of the invention;
• FIG. 4 shows, with an isometric view, a component element of the first transmission unit of the reel-based tightening device according to the first embodiment of the invention;
• FIG. 5 shows, with an isometric view, the components forming the clutch means of a reel-based tightening device according to the invention;
• FIG. 6 shows, with an exploded view, some component elements of the second transmission unit of the reel-based tightening device according to the first embodiment of the invention;
• FIG. 7 shows, with a partially assembled view, some component elements of the second transmission unit of the reel-based tightening device according to the first embodiment of the invention;
• FIGGS. 8A and 8B show, with an upward inner isometric view, the reel-based tightening device - respectively - in the condition with the transmission pawls disengaged from the toothing and in the condition with the transmission pawls engaged with the toothing in a reel-based tightening device according to the first embodiment of the invention;
• FIG. 9 is an exploded view of the components forming the locking means of a reel-based tightening device according to the first embodiment of the invention;
• FIG. 10 shows, with a sectional view, a reel-based tightening device according to the first embodiment of the invention, when it is in an assembled state;
• FIGGS. 11A and 11B show, with exploded views according to different angles, a reel-based tightening device according to a second embodiment of the present invention;
• FIGGS. 12A and 12B show, with exploded views according to different angles, some component elements of the reel-based tightening device according to a second embodiment of the present invention, adapted to enable the controlled release of the traction element.

DETAILED DESCRIPTION OF THE INVENTION

[0020] The present invention relates to a reel-based tightening device 1, 1' adapted to be applied to an article provided with a pair of flaps to be mutually moved towards/away, whether they can overlap one another or simply move towards one another, optionally with the interposition of other elements, to achieve releasable tightening.

[0021] In particular, but not exclusively, a reel-based tightening device 1, 1' according to the present invention can advantageously be used to move the flaps of a sports footwear, such as for example a ski boot, closer to one another or to overlap them, optionally by means of the interposition of a tongue, in order to obtain an adjustable and releasable tightening on the user's foot.

[0022] Terms such as "above", "below", "upper", "lower", "high", "low", "inner", "outer" or the like may be used in the following description; the person skilled in the art will have no difficulty in understanding that these terms refer to a tightening device and to the components thereof in their normal operating position, that is in use, as represented in the attached figures.

[0023] Figures 1A and 1B shows a reel-based tightening device 1 according to a first embodiment of the invention.

[0024] Said device 1 comprises a spool 3 rotatable around a rotation axis X-X and adapted to tension, in a releasable manner, at least one traction element 100, which can advantageously be constrained thereto with at least one first end 100A.

[0025] Said at least one traction element 100 is a flexible and essentially inextensible element, preferably made of metal or of textile or synthetic fibre, consisting for example of a cable, a lace or a stranded cord.

[0026] Said spool 3 is preferably housed in a containing casing 2 defining an inner cavity 21, and it is essentially formed of a pulley provided with at least one annular groove 31 to allow at least a portion of said at least one traction element 100 to be wound and stored therein, and is arranged so as to be axially unmovable and so as to be pivotable around said rotation axis X-X inside the cavity 21 of the containing casing 2, which advantageously has at least one lateral through opening 22 adapted to allow, in use, the sliding passage of said traction element 100.

[0027] Preferably, said casing 2 is associable with a first flap of said pair of flaps of said article, said traction element 100 being associable with a second end 100B and/or with at least one intermediate portion of a second flap of said pair of flaps. Alternatively, said casing 2 can be associated with an element interposed between said pair of flaps, such as for example a tongue, said at least one traction element 100 developing between said pair of flaps along a path configured so as to be able to obtain tightening thereof.

[0028] Said containing casing 2 can preferably be constrained to the surface of the article by means of a mounting base 23, conveniently formed of a plate preferably made of metal, adapted to be arranged, in use, on the outer surface of the article and fixed thereto by means of suitable and known fixing means (not shown in the figures) such as, for example, rivets and to support, on its upper surface, the winding mechanism of the device 1. In particular, said mounting base 23 can preferably be coupled to the containing casing 2 by means of one or more sleeves 23A, inside which the rivets are then inserted for fixing to the surface of the article.

[0029] Said device 1 further comprises an actuating member 4 adapted to be operatively connected to said spool 3 and operable by the user to drive the spool 3 in rotation around said rotation axis X-X at least in a first rotation direction, or winding direction, to wind at least a portion of said at least one traction element 100 thereon, gradually tensioning it in order to obtain a progressive movement of the flaps of the article towards one another and, therefore, the desired tightening action thereof.

[0030] On the other hand, rotating the spool 3 in the opposite rotation direction, or unwinding direction, has the effect of unwinding said at least one traction element 100 from the spool 3, progressively releasing the tensioning it in order to allow the two flaps of the article to move away from one another.

[0031] Said actuating member 4 is preferably formed of a knob, advantageously mounted at the top of said containing casing 2 so as to be axially unmovable but capable of rotating around a rotation axis, preferably coaxial to the rotation axis X-X of the spool 3.

[0032] Advantageously, said rotation axis X-X is defined by a rotation pin 51, preferably formed of a double-diameter rivet, which is deformed at its lower end during assembly to ensure a stable connection between the knob 4 and the mounting base 23 of the device 1. Preferably, said rotation pin 51 is inserted into a rigid sleeve 52, which acts as a spacer between said knob 4 and said base 23 and keeps the components firmly secured without play, as shown in FIG. 10.

[0033] According to an advantageous feature of the invention, said device 1 comprises a first transmission unit 6 comprising a first set of component elements, adapted to cooperate with said actuating member 4 to transmit the rotation of the latter to said spool 3 with a first gear ratio R1 in a first operating condition, a second transmission unit 7 comprising a second set of component elements, adapted to cooperate with said actuating member 4 to transmit the rotation of the latter to said spool 3 with a second gear ratio R2, different from the first gear ratio R1, in a second operating condition, and a switching unit 200 configured to automatically switch the transmission of the rotation between said actuating member 4 and said spool 3 during the winding of said at least one traction element 100 from said first gear ratio R1 to said second gear ratio R2 upon exceeding a upon exceeding a predetermined threshold value of the tension of said traction element 100, which substantially corresponds to exceeding a predetermined threshold value of the torque to be applied by said actuating member 4 during the winding of said at least one traction element 100. In other words, the transmission units 6, 7 are selectively, i.e. alternatively, engaged to transmit the motion of the actuating member 4 to the spool 3 based on the tensioning state of the traction element 100.

[0034] Preferably, said first gear ratio R1 is smaller than said second gear ratio R2. In particular, preferably, said first gear ratio R1 is essentially impartial, i.e. equal to 1, so that the rotation speed of the spool 3 is substantially identical to the rotation speed of the knob 4 imparted by the user. Under this condition, the winding mechanism operates substantially in direct drive, and the force applied by the user to the knob 4 is directly proportional to the tensioning of the traction element 100; therefore, this is very advantageous for the take-up of the traction element 100, during which the tensioning thereof is substantially zero or rather low ("non-tensioned cable" or " slack cable" situation), thus reducing the time needed to be able to start the actual tensioning and, hence, the tightening action.

[0035] On the other hand, said second gear ratio R2 is reducing, i.e. greater than 1 (for example 2:1 or 3:1 or 4:1 ...), so that the rotation speed of the spool 3 is lower than the rotation speed set by the user on the knob 4, but with a higher torque. In this condition, the winding mechanism works with a reduction ratio and the effort perceived by the user is reduced relative to the actual tensioning of the traction element 100; this is very advantageous when the tension on the traction element 100 begins to increase to carry out the desired action of tightening the flaps. This facilitates the user in the tightening operation, also allowing them to be able to set the desired tighten with high precision. Preferably, said second transmission unit 7 comprises a planetary reduction gear, as described below, but it could alternatively comprise, for example, a cycloidal reduction gear.

[0036] Advantageously, said switching unit 200 allows users to automatically switch the transmission path between the actuating member 4 and the spool 3, alternatively engaging the component elements of said first transmission unit 6 or of said second transmission unit 7 based on the tensioning state of the traction element 100, namely, in particular, if it is lower than or exceeds a predetermined threshold value, respectively.

[0037] For example, the threshold value can be defined as ranging from 2 to 5 kg, advantageously 3 kg, which substantially corresponds to a torque to be applied on the actuating member 4 acceptable for an average user. Consequently, the switching unit 200 of the device 1 is configured so that, for a tensioning state of the traction element 100 lower than said threshold value, the tightening device engages the component elements of the first transmission unit 6, operating along a first transmission path with a first gear ratio R1, whereas, for a tensioning state of the traction element 100 higher than or equal to this threshold value, the tightening device engages the component elements of the second transmission unit 7, operating along a second transmission path with a second gear ratio R2.

[0038] According to an advantageous feature of the invention and as explained more in detail below, said switching unit 200 comprises first elastically deformable means 201 and at least one transmission pawl 202. In particular, said first elastically deformable means 201 are operable by said actuating member 4 to move from a first deformation state, in which said actuating member 4 actuates said first transmission unit 6, to a second deformation state, in which said actuating member 4 causes the rotation of said at least one transmission pawl 202 on a plane essentially orthogonal to said rotation axis X-X, in order to actuate said second transmission unit 7.

[0039] Said device 1 further comprises a support or transmission element 60, preferably formed of a substantially plate-shaped body, such as for example a disc, preferably having an essentially annular shape, advantageously made of a polymer or metal material, provided with a first face 60A, or upper face, facing said actuating member 4, and with a second face 60B, or lower face, substantially facing said spool 3 and advantageously provided with a central through hole 60C.

[0040] Said support element 60 is preferably housed in the cavity defined by the knob 4 in an unmovable manner along said rotation axis X-X and is arranged on a plane substantially orthogonal to said rotation axis X-X. Said support element 60 is adapted to support said switching unit 200. Said first face 60A advantageously defines the plane essentially orthogonal to said rotation axis X-X, on which said at least one transmission pawl 202 rotates, the latter not being able to move along said rotation axis X-X.

[0041] Specifically, said actuating member 4 is operatively connected to said support element 60 by means of at least one first transmission pin 41 projecting from an inner surface 4A of the actuating member, conveniently along an axis parallel to the rotation axis X-X, and adapted to engage a first support seat 61 obtained on the upper face 60A of said support element 60, in order to transmit the rotation exerted by the user upon the actuating member 4 to said support element 60.

[0042] Said device 1 further comprises clutch means 8 configured to selectively connect said support element 60 and said spool 3 and preferably comprising a pair of clutch elements 81, 82, which are axially unmovable with respect to one another, one of them being integral to said spool 3, the other being connected to said support element 60.

[0043] In particular, said first clutch element 81 preferably comprises a substantially plate-shaped body, such as a disc, preferably having an essentially annular shape, arranged so as to be integral to said support element 60, in particular constrained in an integral manner to the lower face 60B of the latter, or optionally manufactured as one single piece together with it.

[0044] Said second clutch element 82 also comprises a substantially plate-shaped body, such as a disc, preferably having an essentially annular shape, arranged so as to be integral to said spool 3, in particular preferably keyed thereto by means of one or more mounting pins 34, which project from an upper surface 30A of the spool 3 along axes essentially parallel to said rotation axis X-X and are adapted to be received in corresponding engagement seats 86 obtained on said second clutch element 82.

[0045] Preferably, said clutch elements 81, 82 are provided with respective opposite and facing faces 81A, 82A, arranged orthogonally to said rotation axis X-X and essentially in contact with each other, configured to maintain a kinematic coupling between said clutch elements 81, 82 so that they rotate around said rotation axis X-X in an integral manner, as one single body, in the first operating condition, and to kinematically uncouple said clutch elements 81, 82 along the contact plane thereof in the second operating condition, allowing for a relative rotation between said clutch elements 81, 82.

[0046] Advantageously, the selective kinematic coupling of said clutch elements 81, 82 is developed thanks to second elastically deformable means 83 configured, namely selected so as to have appropriate physical and structural characteristics (shape, size, elastic constant,...) to keep said clutch elements 81, 82 elastically coupled when the acting tangential forces are rather low and to enable the kinematic uncoupling between said clutch elements 81, 82, substantially yielding elastically when the acting tangential forces exceed a given value.

[0047] Preferably, said second elastically deformable means 83 comprise at least one elastic element arranged at one of said two opposite faces 81A, 82A and configured to elastically transition from a first deformation state, or initial deformation state, when the acting tangential forces are rather low, to a second elastic deformation state, as the acting tangential forces increase between said faces 81A, 82A.

[0048] Preferably, said first clutch element 81 has, at the relative face 81A, at least one blind or through engagement seat 85 and, advantageously, a plurality of engagement seats 85 arranged in a circumferential pattern around said rotation axis X-X, preferably evenly spaced.

[0049] Preferably, said second clutch element 82 has, at the relative face 82A, at least one retaining element 84 and said second elastically deformable means 83, the latter being advantageously configured to assume at least a first deformation state, in which they elastically cause said at least one retaining element 84, to which they are operatively connected, to engage said engagement seat 85, thus determining the first operating condition, and a second deformation state, in which they enable the disengagement of said at least one retaining element 84 from said engagement seat 85 so as to permit the kinematic uncoupling of said pair of clutch elements 81, 82.

[0050] Preferably, said first deformation state is an essentially non-deformed or slightly pre-loaded state, said second deformation state corresponding to a greater elastic deformation than said first deformation state.

[0051] Conveniently, said second elastically deformable means 83 have an elastic force that is greater than that of said first elastically deformable means 201.

[0052] In particular, advantageously, said second elastically deformable means 83 comprise at least one leaf spring, substantially formed of a leaf having a first end constrained to the body of said second clutch element 82 at said second face 82A, said retaining element 84 formed of a shaped body, for example a hemispherical body or a body with another geometry (visible in FIG. 2A), operatively connected to said leaf spring, for example arranged at or near the free end of said leaf, adapted to be received and elastically held in a suitably counter-shaped engagement seat 85 of said plurality of engagement seats 85. This embodiment is particularly advantageous as it limits the thickness of the device 1.

[0053] Alternatively, said second elastically deformable means 83 can comprise at least one helical compression spring, for example housed in a seat obtained in the body of said second clutch element 82, adapted to axially urge said at least one retaining element 84 towards said engagement seat 85.

[0054] According to a further alternative, said second elastically deformable means 83 may comprise at least one conical spring, for example located below the body of said second clutch element 82, adapted to urge said at least one retaining element 84 formed of a shaped body obtained on the upper surface of the body of said second clutch element 82 towards a corresponding and counter-shaped engagement seat 85.

[0055] Optionally, the inverted mounting of said clutch elements 81, 82 is also possible, so that the second clutch element 82, comprising said at least one retaining element 84 and said second elastically deformable means 83, is arranged so as to be integral to said support element 60 and said first clutch element 81, provided with at least one engagement seat 85, is arranged so as to be integral to the spool 3. Said clutch elements 81, 82 are in any case axially unmovable, that is they cannot move with respect to one another along the rotation axis X-X of the spool 3, which substantially corresponds to the axial development axis of the device 1.

[0056] Preferably, in order to allow for a better distribution of stresses, said second elastically deformable means 83 comprise a plurality of elastic elements, in particular, as shown in the accompanying figures, a plurality of leaf springs, each adapted to urge a corresponding retaining element 84 in an engagement seat of said plurality of engagement seats 85 obtained on said first clutch element 81.

[0057] Advantageously, the presence of a plurality of engagement seats 85 arranged circumferentially on said first clutch element 81 allows the kinematic coupling between said clutch elements 81, 82 to be resumed at any time, if tangential stresses return below a given limit.

[0058] Alternatively, the selective kinematic coupling of said clutch elements 81, 82 can be generated by the friction between respective faces 81A, 82A in contact with one another, which are then configured, that is selected during the design phase, so as to - for example - have a surface roughness suitable for developing a friction force sufficient to keep said clutch elements 81, 82 kinematically coupled in the first operating condition, but which can be overcome upon reaching and exceeding a given tangential force, calibrated so as to occur while shifting to the second operating condition.

[0059] In this case, advantageously, the static sliding friction force that develops between the two faces 81A, 82A is greater than the elastic force of said first elastically deformable means 201.

[0060] In other words, advantageously, the two clutch elements 81, 82 are configured to remain kinematically coupled, that is to rotate around said rotation axis X-X in an integral manner, namely as one single body, in the first operating condition and to be kinematically uncoupled due to elastic failure or to overcoming of the friction force in the second operating condition, thus enabling a relative rotational movement of the respective faces 81A, 82A along the contact plane thereof, that is, in other words, a relative tangential slip.

[0061] Preferably, said device 1 further comprises a pinion 70, a plurality of gear wheels 74 and a ring gear 75, which are arranged and configured so as to substantially create a planetary reduction gear aimed at reducing the effort perceived by the user during the tensioning of the traction element 100.

[0062] Preferably, said plurality of gear wheels 74 comprises at least three gear wheels 74 rotatably mounted on the upper face of said spool 3 by means of respective mounting pins 34 essentially parallel to the rotation axis X-X of the spool 3 (FIG. 7).

[0063] Said pinion 70 is arranged and extends coaxially to the rotation axis X-X and comprises a stem 71 and a pinion body 72 arranged at the upper end of the stem 71. Said stem 71 is preferably rotatably received in an axial seat 32 obtained in the spool 3.

[0064] As shown in FIGS. 6 and 7, said pinion body 72 comprises a first circumferential toothing 72A and a second circumferential toothing 72B, which are axially spaced apart from one another. In use, said pinion body 72 is positioned at the central through hole 60C obtained on said support element 60, so that said first circumferential toothing 72A is positioned just above or at the upper face 60A of said support element 60, while said second circumferential toothing 72B is arranged substantially near or at the upper face of the spool 3.

[0065] Said gear wheels 74 are provided with corresponding circumferential toothing 74A and are arranged and configured so as to engage both said second circumferential toothing 72B of said pinion body 72 and said ring gear 75 arranged on the inner surface of the containing casing 2.

[0066] According to an advantageous feature of the invention, the switching unit 200, which comprises first elastically deformable means 201 and at least one transmission pawl 202, is conveniently supported on said support element 60 and said support element 60 is operatively connected to said actuating member 4 by means of said first elastically deformable means 201.

[0067] Advantageously, said first elastically deformable means 201 comprise at least one elastic element, preferably formed of a helical spring, conveniently adapted to be loaded by compression. Said first elastically deformable means 201 are operable by said knob 4, and are configured to elastically deform upon exceeding said predetermined threshold value of tensioning of said traction element 100, so as to transition from a first deformation state, in said first operating condition, in which said support element 60 is rotated in an essentially integral manner together with said actuating member 4, to a second deformation state, in said second operating condition, in which it permits and generates a relative rotation between said actuating member 4 and said support element 60.

[0068] Preferably, said at least one elastic switching element 201 is housed in said first support seat 61 obtained on a first face 60A of said support element 60, for the purpose conveniently configured so as to have a longitudinal development along a circumferential path, so that said elastic element 201 substantially lies on the same plane defined by said support element 60.

[0069] Conveniently, said at least one elastic switching element 201 is arranged in the corresponding first support seat 61 so as to substantially abut with the respective ends on the longitudinally opposite edges of the seat, or head edges, said first transmission pin 41 being received in the first support seat 61 in abutment against one of said head edges thereof and being elastically held in said position by the pushing action of said elastic switching element 201.

[0070] In particular, preferably, said at least one first elastic switching element 201 is configured, that is selected during the design phase, so as to have appropriate physical and structural characteristics (shape, size, elastic constant,...) to deform while moving from a first deformation state, which is substantially non-deformed or slightly pre-loaded, in which it counters the sliding of said first transmission pin 41 inside the first support seat 61 so that said support element 60 rotates with said knob 4 in an integral manner, to a second elastic deformation state, greater than said first elastic deformation state, in which it elastically yields, thus allowing said at least one first transmission pin 41 to slide inside the corresponding first support seat 61, hence causing a relative rotation between said support element 60 and the knob 4.

[0071] Advantageously, said at least one first elastic switching element 201 is configured to reach the second deformation state essentially when the predetermined threshold value is exceeded, which advantageously corresponds to the moment when the portion of the traction element 100 that is ineffective or otherwise not useful for tightening the flaps ("slack cable") has been taken up and stored in the annular groove 31 of the spool 3, thus determining the start of the "tensioned" tightening of the flaps.

[0072] Preferably, in order to allow for a better distribution of stresses and to be able to more accurately set the predefined threshold value of tensioning of the traction element 100 beyond which to switch the transmission path through which the rotation of the knob 4 propagates to the spool 3,said first elastically deformable means 201 comprise a plurality of elastic elements, in particular, as shown in the accompanying figures, a plurality of helical springs, each received in a corresponding support seat 61 obtained in said support element 60, each adapted to elastically urge a first transmission pin 41 of a corresponding plurality of first transmission pins 41 projecting from the inner surface 4A of said knob 4 along axes essentially parallel to the rotation axis X-X and movable together with it in an integral manner.

[0073] Said at least one transmission pawl 202 is preferably supported in a freely rotating manner on the plane defined by said upper face 60A of said support element 60 around a respective articulation axis preferably extending parallel to said rotation axis X-X, conveniently defined by a corresponding articulation pin 62 projecting from said support element 60 (visible in FIG. 4) and adapted to be received in a hole 202C made in the body of said transmission pawl 202.

[0074] Advantageously, said at least one transmission pawl 202 is adapted to be caused to rotate by said actuating member 4 on the plane defined by the upper face 60A of said support element 60, when said first elastically deformable means 201 reach or are in the second deformation state.

[0075] In particular, conveniently, said at least one transmission pawl 202 is provided with an engagement tooth 202A and is arranged and configured so as to be caused to rotate by said actuating member 4, preferably by means of a second transmission pin 42 projecting from the inner surface 4A of said knob 4 (visible in FIG. 3) and positioned so as to interact with a control portion 202B of said transmission pawl 202, preferably arranged on the side opposite the engagement tooth 202A with respect to its articulation axis going through said hole 202C and adapted to receive said articulation pin 62.

[0076] Said at least one transmission pawl 202 is therefore rotatably movable around its own articulation axis defined by the articulation pin 62 between a first position, or rest position (shown in FIG. 8A), in which said engagement tooth 202A is far from said first toothing 72A of the pinion 70, and a second position, or transmission position (shown in FIG. 8B), in which said engagement tooth 202A engages said first toothing 72A of the pinion 70, thus being able to cause the rotation of said pinion 70.

[0077] Preferably, for a better distribution of stresses, said switching unit 200 comprises a plurality of transmission pawls 202 as described above, each caused to rotate around its articulation axis by a second transmission pin 42 of a corresponding plurality of second transmission pins 42 projecting from the inner surface 4A of said knob 4 along axes essentially parallel to the rotation axis X-X and movable together with it in an integral manner. As shown in the attached figures, the transmission pawls 202 are preferably arranged so as to be interposed between the elastic elements of said first elastically deformable means 201.

[0078] Said second transmission pins 42 are conveniently arranged radially more on the outside that said first transmission pins 41 and preferably in an offset position with respect to the latter.

[0079] FIG. 2A shows the component elements that conveniently define the first transmission unit 6, namely they are used to transmit the rotation in the first operating condition, in which the intermittent rotation of the knob 4 in the winding direction applied by the user is transmitted to said spool 3 with a first gear ratio R1, in particular preferably essentially impartial, that is equal to 1, along a first transmission path. In this way, advantageously, the time required to recover the traction element 100 is rather reduced. In particular, said first transmission unit 6 substantially comprises said support element 60 and said clutch means 8.

[0080] Specifically, due to the low tensioning of the traction element 100, said switching unit 200 substantially makes the rotation of the knob 4, of the support element 60, connected thereto by means of said at least one first transmission pin 41, and of the spool 3 integral by means of said clutch means 8.

[0081] In fact, in this first operating condition said at least one first transmission pin 41 projecting from said knob 4 is received in a corresponding first support seat 61 obtained on said support element 60 and said at least one elastic switching element 201, which in this phase assumes the first deformation state, holds it in abutment against a head edge of the first support seat 61, elastically counteracting the sliding inside it.

[0082] Furthermore, in said first operating condition, the clutch means 8 are configured so that the clutch elements 81, 82 maintain the kinematic coupling between the respective faces 81A, 82A. In this way, the rotation of the spool 3 is integral to the rotation of the support element 60 and, therefore, of the knob 4.

[0083] While the user continues the intermittent rotation of the actuating member 4 in the winding direction, the "slack cable" is taken up, and the flaps begin to tighten. In this condition, the tension of the traction element 100 progressively increases; when said tension exceeds the predefined threshold value, which depends on and is substantially defined by the structural and physical characteristics of said first elastically deformable means 201, the latter causes the transition, advantageously automatically, that is without the intervention of the user, from the first operating condition to a second operating condition, in which the components conveniently defining the second transmission unit 7, shown in FIG. 2B, are used. Specifically, said second transmission unit 7 comprises at least said pinion 70, extending along said rotation axis X-X and provided with a first circumferential toothing 72A, arranged and configured to be selectively engaged by said at least one transmission pawl 202. Preferably, said second transmission unit 7 further comprises a plurality of gear wheels 74 rotatably mounted on said spool 3 and a ring gear 75 mounted on the containing casing 2 and adapted to cooperate with said gear wheels 74 so as to substantially form a planetary reduction gear.

[0084] In this second operating condition, the transmission pawl 202 thus engages the first circumferential toothing 72A of the pinion 70. The tangential forces generated by this interaction cause the kinematic uncoupling of the clutch means 8, thus kinematically disconnecting the support element 60 and the spool 3.

[0085] Consequently, the rotation of the knob 4 is transmitted to said spool 3 with a second gear ratio R2, in particular preferably a reducing gear ratio, namely greater than 1, along a second transmission path which involves the set of component elements of said second transmission unit 7, thereby reducing the effort required by the user, who will be able to tighten the flaps more easily, hence also being able to achieve the desired tightening with greater precision.

[0086] The operation of the reel-based tightening device 1 according to the present invention for the progressive tensioning of a traction element 100 is described below, starting from the condition in which the traction element 100 is in a release condition, namely it is substantially unwound from the spool 3, and the two flaps to be tightened are far from each other.

[0087] In this condition, the user who wishes to obtain the tightening of the flaps rotates, with intermittent movement, the actuating member 4 around the rotation axis X-X in the winding direction in order to first take up the slack of the traction element 100 and then progressively tensioning the traction element 100.

[0088] In the first step of the winding operation, in which the slack of the traction element 100 is initially taken up, the tension of the latter is substantially zero or in any case rather low. Advantageously, the switching means 200 of the device 1 are configured so that the rotation of the knob 4 is integral to the rotation of the support element 60. In fact, in this condition, said at least one elastic switching element 201 advantageously assumes a first deformation state, in which it elastically counteracts the sliding of said at least one first transmission pin 41 inside the corresponding support seat 61, holding it in abutment against a head edge thereof.

[0089] During this step, said clutch means 8 couple the support element 60 to the spool 3 in an integral manner. As a matter of fact, the clutch elements 81, 82 are configured to remain kinematically coupled. For example, said second elastically deformable means 83 in this step assume a first deformation state, with which they hold said at least one retaining element 84 in engagement in a corresponding engagement seat 85.

[0090] Consequently, the rotation of the knob 4 is transmitted with a first gear ratio R1 equal to 1 to the spool 3, following a first transmission path involving the set of component elements of the first transmission unit 6.

[0091] While the user continues the intermittent rotation of the actuating member 4 in the winding direction, the " slack cable" is taken up and the actual tightening of the flaps begins. In this condition, the tension of the traction element 100 progressively increases; when said tension exceeds the predefined threshold value, said switching unit 200 allows users to switch the transmission path between the actuating member 4 and the spool 3 so as to affect the set of components of said second transmission unit 7.

[0092] Specifically, in the second operating condition, due to the increased tensioning of the traction element 100, the tangential forces acting between the actuating member 4 and the support element 60, in turn integral to the spool 3, deform said first elastically deformable means 201, causing them to move to the second deformation state.

[0093] In other words, the torque applied by the user on the knob 4 also overcomes the elastic force of said first elastically deformable means 201, which deform, shifting from said first deformation state to said second deformation state, thus enabling the sliding of said at least one first transmission pin 41, which is integral to the knob 4, inside the corresponding first support seat 61 obtained in the support element 60, thus causing a relative rotation between the latter and the knob 4.

[0094] The movement of the knob 4 with respect to the support element 60 further causes the movement of said at least one second transmission pin 42 with respect to the articulation pin 62, causing - through interference by contact with the control portion 202B - the rotation of said at least one transmission pawl 202 around its articulation axis, from the rest position (FIG. 8A) to the transmission position (FIG. 8B), in which the corresponding engagement tooth 202A meshes with the first circumferential toothing 72A of the pinion body 72, thus driving the pinion 70 in rotation around the rotation axis X-X.

[0095] The rotation of the pinion 70 also causes the rotation of the second circumferential toothing 72B thereof, which meshes with the circumferential toothing 74A of the gear wheels 74, which, in turn, mesh with the ring gear 75 integral to the containing casing 2, thus causing the rotation of the spool 3 around the rotation axis X-X.

[0096] During this step, the tangential forces acting upon said clutch elements 81, 82 are such as to cause their kinematic uncoupling, allowing them to rotate relative to one another, hence causing the uncoupling of the spool 3 from the support element 60. In particular, said second elastically deformable means 83, which advantageously have an elastic force greater than that of said first elastically deformable means 201, undergo a deformation, assuming the second deformation state, thus allowing said at least one retaining element 84 to be disengaged from the corresponding engagement seat 85 and therefore enabling the kinematic uncoupling of the clutch elements 81, 82.

[0097] Since the rotation movement performed by the user on the knob 4 in the winding step is intermittent, when the user releases the knob 4, said first elastically deformable means 201 elastically return to the first deformation state, thus causing said at least one first transmission pin 41 to go back into abutment against the head edge of the corresponding first support seat 61 and causing the simultaneous backward movement of said at least one second transmission pin 42; this causes the oscillation in the opposite direction of said at least one transmission pawl 202, which then returns to the rest condition, causing the resetting thereof, so as to be able to proceed in a manner similar to what has just been described for the subsequent rotational activation of the knob 4 by the user in the winding direction.

[0098] Advantageously, as better shown in FIG. 9, said device 1 further comprises locking means 9 configured to lock the rotational position progressively reached by the spool 3 during the winding of the traction element 100, for this purpose advantageously provided with a circumferential toothing 33.

[0099] In particular, advantageously, said locking means 9 comprise a first locking pawl 91 received in a lateral cavity 24 of the casing 2 with respect to the housing seat 21 of the spool 3, so that it can rotate around a first oscillation axis R-R, essentially parallel to said rotation axis X-X and preferably defined by a corresponding pin 93, with a movement elastically controlled by first elastic locking means 92, such as, for example, a torsion spring.

[0100] Said first locking pawl 91 is conveniently provided with an engagement tooth 91A configured to engage said circumferential toothing 33 obtained on said spool 3 in order to fix the rotational position progressively reached by it and is articulated to the casing 2 so as to be able to oscillate around the first oscillation axis R-R in order to allow the engagement tooth 91A to pass in succession the teeth of the toothing 33 of the spool 3, in contrast to the elastic action of said first elastic locking means 92.

[0101] According to an advantageous feature, said first elastic locking means 92 comprise a double torsion spring, thanks to which said first locking pawl 91 exhibits a bistable behaviour, as it is able to elastically maintain a first position, or locking position, in which said engagement tooth 91A engages the circumferential toothing 33 of the spool 3 to hold the rotational position progressively reached by the latter during the winding of the traction element 100, and a second position, or release position, in which said engagement tooth 91A is disengaged from the circumferential toothing 33 of the spool 3 to allow said spool 3 to freely rotate in the unwinding direction, so as to enable the quick release of the traction element 100.

[0102] The passage from said locking position to said release position is advantageously determined by the user acting upon a control means P, such as for example a button, operatively connected to the body of said first locking pawl 91 and configured to be accessible through an opening 24A obtained on said casing 2, so as to allow said first locking pawl 91 to move in order to obtain the release of the traction element 100.

[0103] According to an advantageous feature, said locking means 9 further comprise a second locking pawl 94, which is articulated to said first locking pawl 91 around a second oscillation axis V-V, essentially parallel to said rotation axis X-X and preferably defined by a corresponding pin 96, and is operated by second elastic locking means 95, such as for example a torsion spring.

[0104] Said second locking pawl 94 is provided with an engagement tooth 94A adapted to selectively engage the circumferential toothing 33 of the spool 3. In particular, said second locking pawl 94 is arranged and configured so as to be moved by said first locking pawl 91 between a first position, or disengagement position, in which said engagement tooth 94A is far from the toothing 33 of the spool 3, said disengagement position being assumed when said first locking pawl 91 is in the locking position, and an engagement position, in which said engagement tooth 94A engages the toothing 33 of the spool 3, said engagement position being assumed when said first locking pawl 91 is in the release position and, therefore, with the spool 3 rotating around the rotation axis X-X in the unwinding direction to obtain the release of said traction element 100.

[0105] Advantageously, when said first locking pawl 91 is in the release position and, therefore, said second locking pawl 94 is in the engagement position, the latter oscillates around the second oscillation axis V-V in order to allow the engagement tooth 94A to pass in succession over the teeth of the toothing 33 of the spool 3, in contrast to the action of said second elastic locking means 95.

[0106] As soon as the user activates the knob 4 again to obtain the tensioning of the traction element 100, the spool 3 is caused to rotate around the rotation axis X-X in the winding direction; due to the shape of the teeth of the circumferential toothing 33 of the spool 3 and to the arrangement of the engagement tooth 94A, the latter remains engaged in the toothing 33, thus forcing the rotation of said first retaining pawl 91 around the first oscillation axis R-R from the release position to the locking position, allowing it to reset automatically.

[0107] Figures 11A and 11B show a reel-based tightening device 1' according to a second embodiment of the present invention, essentially identical to the device 1 according to the first embodiment but incorporating controlled release means 10 of said at least one traction element 100. In the description below and in the relative figures, structurally or functionally identical elements are referred to with the same reference number used in the description of the first embodiment. The elements that have undergone a structural or functional change are instead indicated with an apex.

[0108] The operation of the tightening device 1' according to the second embodiment also is substantially identical to that already described in relation to the tightening device 1 according to the first embodiment. Therefore, the following description only discloses the operation of said controlled release means 10 to obtain the controlled "step-by-step" release of the traction element 100.

[0109] Said controlled release means 10 advantageously comprise a ring nut 11, which is formed of a body preferably made of a polymer material, mounted at an inner edge of said knob 4' and is arranged so as to be - in use - interposed between the latter and the top of said containing casing 2.

[0110] Said ring nut 11 has an inner toothing 11A adapted to interact with a corresponding circumferential toothing 43 obtained on a peripheral edge of said knob 4' and an outer toothing 11B adapted to interact with a stop appendage 12 projecting upwards from said first locking pawl 91' of said locking means 9'.

[0111] As best seen in Figures 12A and 12B, said inner toothing 11A is advantageously formed of a plurality of inclined blades, which are oriented so as to be elastically deformable when operated by the circumferential toothing 43, when said knob 4' is rotated in the winding direction; however, they are rigid when they are operated by the circumferential toothing 43, when said knob 4' is rotated in the unwinding direction.

[0112] On the other hand, said outer toothing 11B is preferably formed of a plurality of substantially rigid teeth radially projecting outwards from the body of said ring nut 11.

[0113] Said controlled release means 10 further comprise third elastically deformable means 13 arranged and configured so as to elastically counteract the rotation of the knob 4' in the unwinding direction. Specifically, said third elastically deformable means 13 are preferably formed of at least one compression spring housed in a corresponding second support seat 14 obtained on said support element 60' and configured so as to interact with said at least one first transmission pin 41 projecting from the inner surface 4A of said knob 4' to elastically counteract the rotation of the knob 4' in the unwinding direction.

[0114] Preferably, said second support seat 14 adjoins a first support seat 61 adapted to house said at least one elastic element of said first elastically deformable means 201, said at least one first transmission pin 41 being substantially received in the joining point of said first and second support seats 61, 14.

[0115] The operation of the device 1' in the tightening phase is substantially identical to that of the tightening device 1 according to the first embodiment. As a matter of fact, when the knob 4' is rotated intermittently by the user in the winding direction, the first locking pawl 91' allows the rotational position progressively reached by the spool 3 to be maintained with repeated oscillations controlled by the first elastic locking means 92.

[0116] In this condition, the ring nut 11 is essentially inactive, as it is not involved in the operation of the device 1': when the first locking pawl 91' rotates around the first oscillation axis R-R in order to allow the engagement tooth 91A to pass in succession over the teeth of the toothing 33 of the spool 3, this movement moves the stop appendage 12 away from the outer toothing 11B of the ring nut 11, allowing the latter to rotate with the knob 4' in an integral manner, while, when the stop appendage 12 engages the outer toothing 11B of the ring nut 11, the latter remains integral to the casing 2 and the circumferential toothing 43 obtained on the knob 4' slides on its inner toothing 11A thanks to the elastic deformation of the blades that constitute it.

[0117] When the user rotates the knob 4' in the unwinding direction to obtain the controlled release of the traction element 100, the blades that constitute the inner toothing 11A engage with the circumferential toothing 43 of the knob 4', causing the ring nut 11 to rotate in an integral manner together with the knob 4'.

[0118] In this situation, the teeth of the outer toothing 11B of the ring nut 11 impact in succession against the stop appendage 12, inducing the intermittent oscillation of the first locking pawl 91' around the first oscillation axis R-R with a movement elastically controlled by said first elastic locking means 92, so as to allow the engagement tooth 91A to pass in succession over the teeth of the toothing 33 of the spool 3, thereby obtaining the gradual and controlled release of the traction element 100.

[0119] During this gradual release, the winding mechanism works with a gear ratio substantially equal to the first gear ratio R1 since the forces on said spool 3 and on said knob 4' are not sufficient to determine the elastic deformation of said first elastically deformable means 201, thus holding it in the first operating condition.

[0120] The rotational movement of the knob 4' in the unwinding direction is elastically counteracted by the action of said third elastically deformable means 13, which elastically cause said at least one first transmission pin 41 integral to the knob 4' to return to the initial position with each intermittent release thereof operated by the user.

[0121] The controlled release of the traction element 100 obtainable with the device 1' according to the second embodiment of the invention also allows for a micrometric control of the tightening force acting on the flaps, thus increasing the comfort of use for the user.

[0122] Optionally, a reel-based tightening device 1, 1' according to the present invention can be used to tension a plurality of traction elements 100, thereby being able to simultaneously tighten pairs of flaps arranged on different portions of the article with which the device is associated, for example, in case of a sports footwear such as a ski boot, shell and cuff.

[0123] Finally, it should be noted that, with reference to Figures 2A and 2B, the component elements not shown in these figures do not actively participate in the transmission of motion, but they may optionally be moved, for example caused to rotate, as a result of the transmission movement of the active components. For example, in the first operating condition, in which the transmission of motion from the knob 4 to the spool 3 is obtained through said first transmission unit 6, the rotation of the spool 3 with respect to the casing 2 on which the ring gear 75 is obtained, causes the gear wheels 74 and the pinion 70 to passively rotate, however without these elements being involved in the transmission action.

[0124] In conclusion, it is evident from the foregoing that the present invention allows the objects and advantages initially set forth to be achieved. As a matter of fact, the present invention provides a reel-based tightening device that operates with a gear ratio automatically variable as a function of the tension of the traction element 100 and, therefore, of the torque required of the user to operate the actuating member 4, 4' in order to obtain the tightening of a pair of flaps.

[0125] In fact, in a tightening device 1, 1' according to the present invention, when the tension of the traction element 100 is low, the winding mechanism engages a first transmission unit 6, in which the transmission ratio advantageously is equal to 1, thus reducing the time needed to take up the traction element 100 and store it around the spool 3. As soon as the tension of the traction element 100 exceeds a predetermined threshold value, for example equal to about 3 kg, the switching unit 200 incorporated in the tightening device allows for the automatic activation, without the intervention of the user, of a second transmission unit 7, in which the gear ratio is greater than 1, thus leading to a reduction in the effort perceived by the user, who can therefore tighten the flaps easily and effectively.

[0126] It is therefore evident how a reel-based tightening device according to the invention is practical and easy to use.

[0127] In addition, thanks to the presence of the locking means described above, a reel-based tightening device according to the present invention permits the quick release of the traction element and, thanks to the presence of the controlled release means described above, a reel-based tightening device according to the present invention also permits the controlled release of the traction element, so as to enable a fine adjustment of the tightening of the flaps.

[0128] Finally, the invention offers a highly compact reel-based tightening device provided with a lower profile, so that it can advantageous be used for the tightening of sports footwear. As a matter of fact, the switching unit 200, which is responsible for automatically switching the transmission between the first transmission unit 6 and the second transmission unit 7, is configured so that the transition from a first operating configuration to a second operating configuration takes place through the elastic yielding of said first elastically deformable means 201, which therefore permit a relative rotation between the actuating member 4, 4' and the support element 60, 60', thus triggering the rotation of said at least one transmission pawl 202, which meshes with the pinion 70, and causing the kinematic uncoupling of the clutch elements 81, 82.

[0129] The component elements of said device 1, 1', including those that form said switching unit 200, are axially unmovable and the passage between the two operating conditions takes place without any displacement along the rotation axis X-X, thereby minimizing the axial development of the device 1, 1'.

[0130] Furthermore, since in a device 1, 1' according to the present invention the total release of the traction element 100 takes place thanks to the presence of locking means that can be operated by the user through a dedicated control means P, which is accessible through an opening obtained on the casing, the knob 4, 4' maintains a fixed axial position with respect to the casing in any condition, thereby allowing the vertical dimension of the device 1, 1' to be further limited.

[0131] Of course, the present invention is susceptible to numerous applications, modifications or variants, without thereby going beyond the scope of protection as defined by the appended claims.

[0132] Moreover, the materials and equipment used in the present invention, as well as the shape and size of the individual components, may be the most suitable ones depending on the specific needs.

Claims

1. Reel-based tightening device (1, 1') adapted to be applied to an article provided with a pair of flaps to be mutually moved towards/away, said device (1, 1') comprising:

- a spool (3), rotatable around a rotation axis (X-X),

- an actuating member (4, 4'), operatively connectable to said spool (3) and operable by a user to cause said spool (3) to rotate around said rotation axis (X-X) to wind at least a portion of a traction element (100) thereon,

characterized in that it further comprises:

- a first transmission unit (6) comprising a first set of component elements, adapted to cooperate with said actuating member (4, 4') in a first operating condition to transmit the rotation of said actuating member (4, 4') to said spool (3) with a first gear ratio (R1),

- a second transmission unit (7) comprising a second set of component elements, adapted to cooperate with said actuating member (4, 4') in a second operating condition to transmit the rotation of said actuating member (4, 4') to said spool (3) with a second gear ratio (R2), which is different from the first gear ratio (R1), and

- a switching unit (200) configured to switch the transmission between said actuating member (4, 4') and said spool (3) during winding of said at least one traction element (100) from said first gear ratio (R1) to said second gear ratio (R2) upon exceeding a predetermined threshold value of the tension of said traction element (100).

2. The reel-based tightening device (1, 1') according to claim 1, wherein said switching unit (200) comprises first elastically deformable means (201) and at least one transmission pawl (202) rotatably movable on a plane orthogonal to said rotation axis (X-X), said first elastically deformable means (201) being operable by said actuating member (4, 4') to move from a first deformation state, in which said actuating member (4, 4') actuates said first transmission unit (6), to a second deformation state, in which said actuating member (4, 4') causes rotation of said at least one transmission pawl (202), thereby actuating said second transmission unit (7).

3. The reel-based tightening device (1, 1') according to claim 2, wherein said first transmission unit (6) comprises a support element (60, 60') operatively connected to said actuating member (4, 4') by means of said first elastically deformable means (201), and clutch means (8) configured to selectively connect said support element (60, 60') and said spool (3).

4. The reel-based tightening device (1, 1') according to claim 3, wherein said first elastically deformable means (201) comprise at least one elastic element and are configured to elastically deform upon exceeding said predetermined threshold value of the tension of said traction element (100), so as to transition from said first deformation state, in said first operating condition, in which said support element (60, 60') is rotated in an integral manner together with said actuating member (4, 4'), to said second deformation state, in said second operating condition, wherein it generates a relative rotation between said actuating member (4, 4') and said support element (60, 60').

5. The reel-based tightening device (1, 1') according to claim 3 or 4, wherein said clutch means (8) comprise a pair of clutch elements (81, 82), which are axially unmovable with respect to each other, one of them being integral to said spool (3), the other being operatively connected to said support element (60, 60'), said pair of clutch elements (81, 82) being provided with respective opposite and facing faces (81A, 82A), arranged orthogonally to said rotation axis (X-X) and essentially in contact with each other and configured to maintain a kinematic coupling when said first elastically deformable means (201) are in the first deformation state and to be kinematically uncoupled from each other when said first elastically deformable means (201) are in the second deformation state, so as to cause a relative rotation movement of said clutch elements (81, 82).

6. The reel-based tightening device (1, 1') according to claim 5, wherein a first clutch element (81) of said pair of clutch elements (81, 82) comprises a face (81A) provided with at least one engagement seat (85), a second clutch element (82) of said pair of clutch elements (81, 82) being provided with a face (82A) provided with second elastically deformable means (83) and at least one retaining element (84), said second elastically deformable means (83) being configured to assume a first deformation state, in which they elastically urge said at least one retaining element (84) to engage said at least one engagement seat (85), and a second deformation state, in which they allow said at least one retaining element (84) to be disengaged from said engagement seat (85) so as to kinematically uncouple said pair of clutch elements (81, 82).

7. The reel-based tightening device (1, 1') according to one or more of the claims from 2 to 6, wherein said second transmission unit (7) comprises a pinion (70) extending along said rotation axis (X-X) and having a first circumferential toothing (72A) adapted to be selectively engaged by said at least one transmission pawl (202).

8. The reel-based tightening device (1, 1') according to claim 7, wherein said at least one transmission pawl (202) comprises an engagement tooth (202A) and is adapted to be rotated by said actuating member (4, 4') when said first elastically deformable means (201) are in a second deformation state, from a first position, wherein it is spaced from said first toothing (72A), to a second position, wherein it engages said first toothing (72A) to drive said pinion (70) in rotation around said rotation axis (X-X).

9. The reel-based tightening device (1, 1') according to claim 7 or 8, wherein said second transmission unit (7) further comprises a plurality of gear wheels (74) rotatably mounted on said spool (3) and capable of being rotate by said pinion (70), and a ring gear (75) mounted on a containing casing (2) of said spool (3) and adapted to cooperate with said gear wheels (74).

10. The reel-based tightening device (1, 1') according to claim 9, wherein said pinion (70) comprises a stem (71) adapted to be received in a seat (32) formed in said spool (3) and a pinion body (72) comprising said first circumferential toothing (72A) and a second circumferential toothing (72B) axially spaced apart, said second circumferential toothing (72B) meshing with said plurality of gear wheels (74).

11. The reel-based tightening device (1, 1') according to any one of the preceding claims, wherein said spool (3) comprises a circumferential toothing (33), said device (1, 1') further comprising locking means (9, 9') configured to lock the spool (3) in any rotational position progressively reached when it is rotated in the winding direction, said locking means (9, 9') comprising a first locking pawl (91, 91') rotatably mounted to said containment casing (2) around a first oscillation axis (R-R) and first elastic locking means (92), said first locking pawl (91, 91') being provided with an engagement tooth (91A) configured to engage in succession the teeth of said circumferential toothing (33) of said spool (3) with a movement counteracted by said first elastic locking means (92).

12. The reel-based tightening device (1, 1') according to claim 11, wherein said first elastic locking means (92) comprise a double torsion spring configured to hold said first locking pawl (91, 91') in a first position, where said engagement tooth (91A) elastically engages the circumferential toothing (33) of said spool (3), and in a second position, where said engagement tooth (91A) is disengaged from the circumferential toothing (33) of said spool (3), allowing free rotation of said spool (3) in the unwinding direction.

13. The reel-based tightening device (1, 1') according to claim 12, wherein said locking means (9, 9') further comprise a second locking pawl (94) articulated to said first locking pawl (91) around a second oscillation axis (V-V) and operated by second elastic locking means (95), said second locking pawl (94) being provided with an engagement tooth (94A) configured to engage said circumferential toothing (33) when said first locking pawl (91, 91') is in said second position.

14. The reel-based tightening device (1') according to any one of the claims from 11 to 13, comprising controlled release means (10) of said at least one traction element (100) comprising at least one ring nut (11) provided with an inner toothing (11A) adapted to interact with a circumferential toothing (43) obtained on said actuating member (4') and with an outer toothing (11B) adapted to interact with a stop appendage (12) projecting from a first locking pawl (91') of said locking means (9'), said controlled release means (10) further comprising third elastically deformable means (13) arranged and configured so as to elastically counteract the rotation of said actuating member (4') in the unwinding direction.

15. Sports footwear provided with at least one pair of flaps to be tightened, comprising at least one reel-based tightening device (1, 1') according to any one of the preceding claims.

Drawing