TECHNICAL FIELD

The present invention regards a bicycle of the folding type, i.e. a bicycle that can be folded to switch from a use configuration to a minimum overall dimension configuration, and vice versa.

PRIOR ART

Known are folding bicycles having a frame provided with: a front fork to which a front wheel is associated, a rear triangle to which a rear wheel is associated and a beam connecting the front fork with the rear triangle.

Such bicycles also comprise a steering beam designed to drive the front fork in rotation with respect to a steering axis and a saddle post rigidly fixed to the rear triangle.

Integrally joined to steering column is a handlebar, while removably associated to the saddle post is a saddle.

This type of bicycles is characterised by the fact that the beam consists of two sections, approximately with equal axial extension, which are hinged to each other so as to be able to substantially fold the frame into two.

Though allowing to reduce the overall dimensions of the bicycle when not being used with respect to a conventional bicycle, these known bicycles are still excessively cumbersome. For example, even once folded they are still too large to be kept away in a small bag, for example a bag of the business suitcase type so as to allow comfortable transportation thereof.

An object of the present invention is to overcome said problems of the prior art through a solution that is simple, rational and inexpensive.

Such object is attained by the characteristics of the invention, which are outlined in the independent claim. The dependent claims outline preferred and/or particularly advan tageous aspects of the invention.

DESCRIPTION OF THE INVENTION

The invention particularly provides a bicycle of the folding type, comprising a frame provided with: a front fork to which a front wheel is rotatably associated, a rear triangle to which a rear wheel is rotatably associated, and a beam interposed between the front fork and the rear triangle, wherein said beam comprises: a first section to which the front fork is rotatably associated with respect to a steering axis, a second section as sociated to the rear triangle, and a third section, which at a first end is hinged by means of a first hinge to the first section and at a second end it is hinged to the second section by means of a second hinge.

Thanks to such solution, once folded the bicycle occupies a smaller volume with re spect to the prior art devices.

The characteristics below, which are subject of the dependent claims, allow - inde pendently or combined with each other - to reduce the volume occupied by the folded bicycle further, in that they allow to effectively occupy the available empty volumes. According to an aspect of the invention, the first hinge defines a first hinging axis and the second hinge defines a second hinging axis (different from the first hinging axis), the hinging axes being designed to lie on vertical planes.

According to another aspect of the invention, the first hinging axis may be tilted be tween 40° and 70° with respect to a central axis of the third section.

This characteristic allows to reduce the overall dimensions in that it allows to approach the front fork to the third section further.

According to a further aspect of the invention, the second hinging axis is tilted between 50° and 80° with respect to a central axis of the third section.

The reduction of the overall dimensions is due to the possibility of approaching the rear triangle and the third section further, thus centring the masses.

Another aspect of the invention provides for that the hinging axes can be eccentric with respect to the third section (i.e. they cannot intersect the third section).

This allows to mutually superimpose the sections of the beam in the most effective and approached manner possible, in that given that the axes are eccentric, the maximum rotation allowed between the sections is not limited by the transversal overall dimen sions of the sections.

Furthermore, the frame may comprise a steering column connected to the front fork and a handlebar to rotatably drive said steering column in rotation, the steering column comprising a lower section, associated to the front fork, and an upper section associ ated to the handlebar and connected to the lower section by means of a hinge.

For example, the hinge may define a hinging axis lying on a plane transversal to the steering axis and the second section of the steering column may have a slot whose width, in a direction parallel to a rotation axis of the front wheel with respect to the front fork, is greater than the width of the front wheel in such direction.

In this manner, the overall dimension represented by the steering column is consider ably small, in that said steering column can be folded on the front wheel, hence em bracing it at least partially.

According to a further aspect of the invention, the frame may comprise a saddle post, which is associated to the rear triangle by means of a hinge.

For example, the hinge defines a rotation axis parallel to a rotation axis of the rear wheel with respect to the rear triangle and the saddle post has a slot whose width, in a direction parallel to the rotation axis of the rear wheel with respect to the triangle, is greater than the width of the rear wheel in such direction.

In this manner, the overall dimension represented by the saddle post is considerably small, in that said saddle post can be folded on the rear wheel, hence embracing it at least partially.

Furthermore, it may be provided for that the bicycle may comprise an electric motor, mechanically connected to the rear wheel and a battery suitable to power-supply the electric motor, housed in a reception cavity provided on the third section.

The invention also provides a kit comprising a folding bicycle as described above and a bag suitable to contain the bicycle arranged in a folded configuration.

This solution allows to provide a kit that allows the transportation of the bicycle in a simple and comfortable manner.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the invention will be apparent from reading the following description - provided by way of non-limiting example - with reference to the figures illustrated in the attached drawings.

Figure 1 is a side lateral view of a folding bicycle according to the invention, when it is in a use configuration (suitable for riding).

Figure 2 is a view of the bicycle of figure 1 from a rear lateral view.

Figure 3 is a perspective view of the bicycle of figures 1 and 2.

Figure 4 is a perspective view of the bicycle of figure 3 in an intermediate configuration between when being used and a folded configuration.

Figure 5 is a perspective view of the bicycle of figure 4 in an intermediate configuration subsequent to the one illustrated in figure 4.

Figure 6 is a perspective view of the bicycle of figure 5 in an intermediate configuration subsequent to the one illustrated in figure 5.

Figure 7 is a perspective view of the bicycle of figure 5 in an intermediate configuration subsequent to the one illustrated in figure 5 and alternative to the one of figure 6. Figure 8 is a perspective view of the bicycle of the previous figures, illustrated in the folded configuration, i.e. fully folded and put into a bag.

Figure 9 is a side lateral view of an alternative embodiment of the folding bicycle ac cording to the invention, when it is in a use configuration (suitable for riding).

Figure 10 is a lateral view of the bicycle of figure 9 in a partially folded configuration. Figure 1 1 is a lateral view of the bicycle of figures 9 and 10 in a fully folded configura tion.

DETAILED DESCRIPTION

With particular reference to such figures, a bicycle 1 of the folding type, i.e. a bicycle 1 which - starting from a use configuration (suitable for riding) can be folded in a folded configuration in which it has small overall dimensions and vice versa, is indicated in its entirety with 10. For example, in a folded configuration, the bicycle 1 can be closed in a bag V. For example, a bag V with dimensions smaller than 50 x 40 x 15 cm.

The bicycle 1 comprises a frame 5, a front wheel 10 rotatably associated to the frame 5 and a rear wheel 15, also rotatably associated to the frame 5. Such wheels have the same diameter.

Each wheel 10,15 comprises a central hub departing from which is a plurality of spokes which fix the hub to a rim onto which a tyre is mounted.

The frame 5 comprises a front fork 20 rotatably associated to which is the front wheel 10 with respect to a front rotation axis A, i.e. rotatably associated to which is the hub of the front wheel 10 with respect to the front rotation axis A.

The front fork 20 comprises two arms 25, substantially parallel and arranged adjacent to the front wheel 10, and a steering plate 30 which rigidly connects the two arms 25. The front wheel 10 is rotatably fixed to the arms 25, with respect to the front rotation axis A, at the ends opposite to the steering plate 30.

The front fork 20 comprises a steering pivot (not illustrated) rigidly fixed to the steering plate 30 and which extends therefrom in the opposite direction with respect to the front wheel 10. Said pivot defines a steering axis S.

The frame 5 comprises a steering column 35 suitable to support a handlebar 40 of the bicycle 1 removably fixed thereto. The steering column 35 is connected to the front fork 20, i.e. it is integrally joined in rotation to the steering pivot of the front fork 20.

The steering column 35 comprises a slot 45, i.e. a through hole which fully passes through the steering column 35, which has a width (minimum), in direction parallel to the front rotation axis A, greater than the width in the same direction as the front wheel 10.

Furthermore, said slot 45 has a length, in the direction of the steering axis S, comprised between 0.4 and 0.9 times the total length, in the same direction, of the entire steering column 35.

The slot 45 has a through central axis which lies on a plane transversal, for example perpendicular, to the front rotation axis A of the front wheel 10.

The slot 45 is positioned in proximity of the end of the steering column 35 which sup ports the handlebar 40, with respect to the end proximal to the fork.

The steering column 35 is connected to the front fork 20, i.e. to the steering pivot, by interposing a front hinge 50. In particular, the front hinge 50 is directly interposed be tween an end of the steering column 35 distal from the handlebar 40 and the steering pivot.

The front hinge 50 defines a front hinging axis C parallel to the rotation axis A of the front wheel 10. Preferably, the front hinge 50 provides a single degree of freedom be tween the front fork 20 and the steering column 35, the degree of freedom being the rotation of the steering column 35 with respect to the fork around the front hinging axis 50 C.

The front hinge 50 is configured so as to allow the rotation of the steering column 35 with respect to the front fork 20 between a first position, in which the steering column 35 is coaxial to the steering pivot, and a second position, in which the steering column 35 projects cantilevered with respect to the front fork 20 towards the front wheel 10.

In particular, in the second position, the slot 45 of the steering column 35 partially em braces the front wheel 10.

Furthermore, the steering column 35 may have a longitudinal extension so that, in the rotation with respect to the front hinging axis and between the first position and the second position, does not intersect a plane which is tangent to the front wheel in a point of said front wheel at the maximum distance from the front hinge (defined by the intersection of the wheel with the longitudinal axis of an arm 25 of the front fork 20). The front hinge 50 is also provided with a locking system, configured for selectively locking the hinge in the first position.

Furthermore, the front hinge 50 is configured to prevent a rotation of the steering col umn 35 with respect to the front hinging axis C from the first position towards the rear wheel 15.

In the embodiment illustrated in the drawings, the front hinge 50 comprises a first flat plate fixed without degrees of freedom to the steering pivot and a second flat plate fixed without degrees of freedom to the steering column 35, the flat plates being hinged to each other at two respective edges, and for example they are superimposed at con tact along respective larger faces when the steering column 35 is in the first position. The front hinge 50 also comprises a deadbolt (not illustrated) suitable to be inserted into respective seats obtained in the first plate and in the second plate when the plates are at contact and said seats are aligned and arranged coaxially.

The frame 5 comprises a rear triangle 55 rotatably associated to which is the rear wheel 15 with respect to a rear rotation axis B, i.e. rotatably associated to which is the hub of the rear wheel 15 with respect to the rear rotation axis B.

The rear triangle 55, in the illustrated embodiment, is substantially shaped as a fork provided with two arms 60 which laterally wrap around the rear wheel 15 and to which said rear wheel 15 is rotatably associated with respect to the rear rotation axis B. In particular, the arms 60 are shaped as flat plates, for example generally triangular shaped, connected to each other by means of a connection bar 65.

Said flat plates lie on planes parallel and perpendicular to the rear rotation axis B.

For example, said flat plates have thickness comprised between 2 mm and 10 mm. The frame 5 comprises a saddle post 70 associated to the rear triangle 55, for example to the stiffening bar of the rear triangle 55, and a saddle 75 removably fixed to the saddle post 70.

The saddle post 70 comprises a slot 80, i.e. a through hole which fully passes through the steering column 70, which has a width (minimum), in direction parallel to the rear rotation axis B, greater than the width in the same direction as the rear wheel 15. Furthermore, said slot 80 has a length, in the direction of a longitudinal axis of the saddle post 70, comprised between 0.4 and 0.9 times the total length, in the same direction, of the entire saddle post 70.

The slot 80 is positioned in proximity of the end of the saddle post 70 which supports the saddle 75, with respect to the end proximal to the steering pivot.

The slot 80 has a through central axis which lies on a plane transversal, for example perpendicular, to the rear rotation axis B of the rear wheel 15.

The saddle post 70 is connected to the rear triangle 55 by interposing a rear hinge 75. In particular, the rear hinge 75 is directly interposed between an end of the saddle post 70 distal from the saddle 75 and the rear triangle 55. For example, the rear hinge 75 is associated to the arms 60 or to the connection bar 65.

The rear hinge 75 defines a rear hinging axis D, which is parallel to the rear rotation axis B of the rear wheel 15. Preferably, the rear hinge 75 provides a single degree of freedom between the rear triangle 55 and the saddle post 70, the degree of freedom being the rotation of the saddle post 70 with respect to the rear triangle 55 around the rear hinging axis D.

The rear hinge 75 is configured so as to allow the rotation of the saddle post 70 with respect to the rear triangle 55 between a first use position, wherein the distance be tween an upper end of the saddle post 70 distal from the rear hinge 15 is maximum, and a second position, wherein the saddle post 70 projects cantilevered from the rear triangle 55 towards the rear wheel 15 and the distance between said upper end and the rear wheel 15 is minimum.

In particular, in the second position, the slot 80 of the saddle post 70 partially embraces the rear wheel 15.

Furthermore, the saddle post 70 may have a longitudinal extension so that, in the ro tation with respect to the rear hinging axis D between the first position and the second position, does not intersect a plane which is tangent to the rear wheel in a point of said rear wheel at the maximum distance from the rear hinge.

The rear hinge 75 is also provided with a locking system, configured for selectively locking the hinge in the first position.

Furthermore, the rear hinge 75 is configured to prevent a rotation of the saddle post 70 with respect to the rear hinging axis D from the first position towards the front wheel In the embodiment illustrated, the rear hinge 75 comprises a first flat plate fixed without degrees of freedom to the rear triangle 55 and a second flat plate fixed without degrees of freedom to the saddle post 70, the flat plates being hinged to each other at two respective edges, and for example they are superimposed at contact along respective larger faces when the saddle post 70 is in the first position.

The rear hinge 75 also comprises a deadbolt (not illustrated) suitable to be inserted into respective seats obtained in the first plate and in the second plate when the plates are at contact and said seats are aligned and arranged coaxially.

The frame 5 comprises a beam 90, for example straight, which joins the front fork 20 to the rear triangle 55, i.e. the beam 90 is directly interposed between the front fork 20 and the rear triangle 55. The beam 90 is rigid, for example it is an extended tubular body. Furthermore, it has a longitudinal axis, for example lying on a plane perpendic ular to the rear rotation axis B.

In the illustrated embodiment, the beam 90 is for example a single extended body which has an axial end directly associated to which is the front fork 20 and an opposite axial end associated to which is the rear triangle 55.

The front fork 20 is rotatably associated to the beam 90 with respect to the steering axis S and the rear triangle 55 is rigidly fixed to the beam 90.

In particular, the axial end to which the front fork 20 is associated is provided with a tubular portion 95 suitable to fittingly receive the steering pivot and to allow the relative rotation with respect to the steering axis S.

The opposite axial end of the beam 90 associated to the rear triangle 55 is, for exam ple, welded or bolted to the arms 60 of the rear triangle 55.

The beam 90 has an extension in the direction of the longitudinal axis thereof substan tially comprised between 1 .8 and 2.6 times a diameter of the front wheel 10, preferably about 2.2 times the diameter of the front wheel 10.

The beam 90 comprises a first section 100, for example tubular, preferably with rec tangular cross-section, to which the front fork 20 is rotatably associated with respect to the steering axis. For example, the first section 100 of the beam 90 has the tubular portion 95 suitable to receive the steering pivot of the front fork 20.

The first section 100 is shaped as an extended body, for example having an extension in the direction of the axis thereof, i.e. of the longitudinal axis of the beam 90, com prised between 0.5 and 0.7 times a diameter of the front wheel 10, preferably about 0.6 times the diameter of the front wheel 10.

Furthermore, the first section 100 has an extension in the direction of the axis thereof, i.e. of the longitudinal axis of the beam 90, comprised between 120 mm and 175 mm, preferably about 150 mm.

The frame 5 comprises a second section 105, for example tubular, which is rigidly fixed, for example welded, to the rear triangle 55, for example it is welded to the con nection bar 65 of the rear triangle 55 or to the saddle post 70 of the rear triangle 55.

In the illustrated embodiment, the second section 105 is fixed to the rear triangle 55 in proximity of the rear hinge 75.

The second section 105 has an extension in the direction of the longitudinal axis of the beam 90, comprised between 0.05 and 0.3 times a diameter of the front wheel 10, preferably about 0.07 times the diameter of the front wheel 10.

The frame 5 further comprises a third section 1 10, for example tubular, interposed between the first section 100 and the second section 105, preferably shaped as a straight extended body.

The third section 1 10 is extended-shaped and it has a central axis T, for example inci dent and transversal to the steering axis S when the bicycle 1 is in use.

Furthermore, the central axis T lies on a plane perpendicular to the front rotation A and rear rotation B axes when the bicycle is in use.

In particular, the third section 1 10 has a first end associated to the first section 100 and a second opposite end associated to the second section 105.

In particular, the frame 5 comprises a first hinge 1 15 which connects, for example di rectly, the first section 100 to the third section 1 10.

The first hinge 1 15 defines a first hinging axis E which lies on a substantially vertical plane when the bicycle 1 is in use. I.e., when the bicycle 1 is in use, the first hinging axis E lies on a plane perpendicular to the rear rotation axis B.

The first hinging axis E is tilted with respect to the central axis T of the third section 1 10, for example between 40° and 70°, i.e. it is tilted with respect to the central axis T of the third section 1 10 to form an acute angle comprised between 40° and 70°, pref erably between 51 ° and 59°. In the illustrated embodiment, the acute angle measures 55°.

I.e., the projection of the first hinging axis E on a centreline plane (substantially vertical) of the third section 1 10 containing the central axis T, the third section 1 10 forms - with said central axis T - an acute angle comprised between 40° and 70°, preferably be tween 51 ° and 59°. In the illustrated embodiment, the angle measures 55°.

The first hinging axis E is eccentric with respect to the third section 1 10, for example the first hinging axis E is eccentric with respect to a centreline axis of the third section 1 10 parallel to the central axis T of the third section 1 10.

The first hinge 1 15 is configured so as to allow the relative rotation between the first section 100 and the third section 1 10 between a first position, wherein the first section 100 is aligned with the third section 1 10, i.e. they are both aligned with the longitudinal axis of the beam 90, or still the respective longitudinal axes are aligned, and a second position, wherein the first section 100 is arranged at least partially adjacent, for exam ple laterally superimposed, to the third section 1 10.

In particular, in the second position, the front wheel 10 is arranged laterally adjacent to the third section 1 10.

When switching from the first position to the second position, the first section 100 ro tates substantially by 180° with respect to the third section 1 10.

Furthermore, the first hinge 1 15 is configured to allow the rotation of the first section 100 with respect to the third section 1 10 approaching and moving apart from a single side of the third section 1 10, with respect to a centreline plane of the third section 1 10 parallel to the first hinging axis.

I.e., the third section 1 10 has a first side and a second side, opposite with respect to the centreline plane of the third section 1 10 parallel to the first hinging axis, and the first hinge 1 15 is configured to allow the rotation of the first section 100 with respect to the third section 1 10 only approaching and moving apart from a single side of the third section 1 10, for example the first side.

The first hinge 1 15 is also provided with a locking system, configured for selectively locking the hinge in the first position.

In the illustrated embodiment, the first hinge 1 15 comprises a first flat plate fixed with out degrees of freedom to the third section 1 10 and a second flat plate fixed without degrees of freedom to the third section 100, the flat plates being hinged to each other at two respective edges, and for example they are superimposed at contact along re spective larger faces when the first section 100 is in the first position. The edges to which the plates are hinged project externally cantilevered with respect to the corre sponding sections.

The first hinge 1 15 also comprises a locking deadbolt (not illustrated) suitable to be inserted into respective seats obtained in the first plate and in the second plate when the plates are at contact and said seats are aligned and arranged coaxially.

The frame 5 also comprises a second hinge 120 which connects, for example directly, the second section 105 to the third section 1 10.

In an alternative embodiment (not illustrated), the second hinge 120 is directly inter posed between the third section 1 10 and the rear triangle 55, i.e. the hinge is directly interposed between the third section 1 10 and the connection bar 65 or the saddle post 70.

Or still, in such embodiment, the beam 90 solely comprises a first section 100 and a second section 105, wherein the first section 100 - at one end - is directly associated to the fork, and wherein the second section 105 is hinged - at one end - to the rear triangle 55 and - at the opposite end - to the first section 100.

The second hinge 120 defines a second hinging axis F which lies on a substantially vertical plane when the bicycle 1 is in use. I.e., when the second hinging axis E lies on a plane perpendicular to the rear rotation axis B.

The first hinging axis E and the second hinging axis F lie on parallel and juxtaposed planes with respect to a centreline axis of the third section 1 10 containing the central axis T of the third section 1 10.

The second hinging axis F is tilted with respect to the central axis T of the third section 1 10, for example between 50° and 80°. The second hinging axis F is tilted with respect to the central axis T of the third section 1 10, to form an acute angle comprised between 50° and 80°, preferably between 61 ° and 69°. In the illustrated embodiment, the angle measures 65°.

I.e., the projection of the second hinging axis F on a centreline plane (substantially vertical) of the third section 1 10 containing the central axis T, the third section 1 10 forms - with said central axis T - an acute angle comprised between 50° and 80°, pref erably between 61 ° and 69°. In the illustrated embodiment, the angle measures 65°. The second hinging axis E is eccentric with respect to the third section 1 10, for example the second hinging axis E is eccentric with respect to a centreline axis of the third section 1 10 parallel to the central axis T of the third section 1 10.

The second hinge 120 is configured so as to allow the relative rotation between the second section 105 and the third section 1 10 between a first position, wherein the second section 105 is aligned with the third section 1 10, i.e. they are both aligned with the longitudinal axis of the beam 90, or still wherein the respective longitudinal axes are aligned, and a second position, wherein the second section 105 is arranged at least partially adjacent, for example laterally superimposed, to the third section 1 10.

In particular, in the second position, the rear wheel 15 is arranged laterally adjacent to the third section 1 10 at the side of the third section 1 10 opposite with respect to the one arranged adjacent to the first section 100 when the first hinge is in the second position.

When switching from the first position to the second position, the second section 105 rotates substantially by 180° with respect to the third section 1 10.

Furthermore, the second hinge 120 is configured to allow the rotation of the second section 105 with respect to the third section 1 10 approaching and moving apart from a single side of the third section 1 10, with respect to a centreline plane of the third section 1 10 parallel to the second hinging axis.

I.e., the second hinge 120 is configured to allow the rotation of the second section 105 with respect to the third section 1 10 solely approaching and moving away from a single side of the third section 1 10, for example the second side.

The second hinge 120 is also provided with a locking system, configured for selectively locking the hinge in the first position.

In the illustrated embodiment, the rear hinge 120 comprises a first flat plate fixed with out degrees of freedom to the third section 1 10 and a second flat plate fixed without degrees of freedom to the second section 105, the flat plates being hinged to each other at two respective edges, and for example they are superimposed at contact along respective larger faces when the second section 105 is in the first position. The edges to which the plates are hinged project externally cantilevered with respect to the corre sponding sections.

The second hinge 120 also comprises a locking deadbolt (not illustrated) suitable to be inserted into respective seats obtained in the first plate and in the second plate when the plates are at contact and said seats are aligned and arranged coaxially.

In the illustrated embodiment, the beam 90 solely consists of the first section 100, of the second section 105 and of the third section 1 10, which is hinged to the opposite ends respectively by means of the first hinge 1 15 and the second hinge 120 to the respective sections.

The frame 5 of the bicycle 1 is at least partially made of aluminium and/or composite materials.

The bicycle 1 further comprises a pair of pedals, for example of the folding or remova ble type, suitable to drive - under the effort of the user - a transmission unit connected to the rear wheel 15 and associated to the rear triangle 55. Such pair of pedals is hinged to the rear triangle with respect to a hinging axis P, substantially perpendicular to the front A and rear B rotation axes.

The bicycle 1 may also comprise an electric motor connected to the rear hub connected to the rear wheel 15, the motor being actuated by a battery housed in the third section 1 10.

Figures 9-1 1 illustrate an alternative embodiment of the bicycle according to the inven tion. Such bicycle T comprises a first hinge 1 15 which is configured to be movable between a first position, in which the first section 100 is aligned with third section 1 10, and a second position in which the front wheel 10 is arranged laterally adjacent to the third section 1 10, and the second hinge 120 which is configured to be movable be tween a first position, in which the second section 105 is aligned with the third section, and a second position, in which the rear wheel 15 is arranged laterally adjacent to the third section 1 10, on a side of the third section 1 10 opposite to the one with respect to which the front wheel is arranged adjacent when the first hinge is in the second position thereof.

In particular, the bicycle 1 and the bicycle 1’ have a ratio between the length of the third section 1 10 and the diameter of the front wheel 10, a ratio between the distance of the rear rotation axis B from the hinging axis F and the diameter of the front wheel 10, a ratio between the distance of the rear rotation axis B from the central axis T and the diameter of the front wheel 10, a ratio between the distance of the hinging axis P from the hinging axis F and the diameter of the front wheel 10, a ratio between the distance of the hinging axis P from the hinging axis F and the diameter of the front wheel 10, a ratio between the distance of the front rotation axis A from the hinging axis E and the diameter of the front wheel 10, a ratio between the distance of the front rotation axis A from the central axis T and the diameter of the front wheel 10, wherein such ratios are correlated to each other so that when the first hinge 1 15 and the second hinge 120 are in the respective second positions, the front wheel is arranged laterally adjacent to the third section and the rear wheel 15 is arranged laterally adjacent to the third section 1 10, at one side of the third section 1 10 opposite to the one with respect to which the front wheel is arranged adjacent when the first hinge is in the second position thereof, substantially so that the third section is interposed at least partly be tween said wheels.

Furthermore, the bicycle 1’, just like the bicycle 1 , is configured so that when it is in the folded configuration, i.e. when the first hinge and the second hinge are in the respective second positions, the maximum thickness of the bicycle in a direction parallel to the front rotation axis A is smaller than 16cm.

The bicycle T illustrated in figures 9-1 1 substantially has the technical characteristics described up to now regarding the bicycle 1 illustrated in figures 1 -8 contrary to the following dimensional ratios, the dimensional ratios replacing the dimensional ratios of the bicycle 1 of figures 1 -8.

The first section 100 has an extension in the direction of the axis thereof, i.e. The lon gitudinal axis of the beam 90, comprised between 0.1 and 0.3 times a diameter of the front wheel 10, preferably between 0.18 and 0.24 times the diameter of the front wheel 10.

The second section 105 has an extension in the direction of the longitudinal axis of the beam 90, smaller than 0.1 times a diameter of the front wheel 10, preferably smaller than 0.05 times the diameter of the front wheel 10.

The third section 1 10 has an extension in the direction of axis thereof, i.e. of the longi tudinal axis of the beam 90, comprised between 0.8 and 1 .2 times a diameter of the front wheel 10, preferably between 0.95 and 1 .15 times the diameter of the front wheel 10.

The first hinging axis E is tilted with respect to the central axis T of the third section 1 10, for example between 40° and 70°, i.e. it is tilted with respect to the central axis T of the third section 1 10 to form an acute angle comprised between 40° and 70°, pref erably between 49° and 62°.

The second hinging axis F is tilted with respect to the central axis T of the third section 1 10, to form an acute angle comprised between 60° and 85°, preferably between 65° and 75°. In the illustrated embodiment, the angle is comprised between 68° and 72°. The front rotation axis A has a distance L1 from the longitudinal axis of the beam 90, i.e. from the central axis T, comprised between 0.5 and 0.8 times the diameter of the front wheel 10, for example comprised between 0.6 and 0.7 times the diameter of the front wheel 10, preferably comprised between 0.63 and 0.67 times the diameter of the front wheel 10.

The front rotation axis A has a distance L2 from the hinging axis E, comprised between 0.55 and 0.85 times the diameter of the front wheel 10, for example comprised between 0.65 and 0.75 times the diameter of the front wheel 10, preferably comprised between 0.68 and 0.73 times the diameter of the front wheel 10.

The rear rotation axis B has a distance L3 from the longitudinal axis of the beam 90, i.e. from the central axis T, comprised between 0.2 and 0.4 times the diameter of the front wheel 10, for example comprised between 0.27 and 0.37 times the diameter of the front wheel 10, preferably comprised between 0.29 and 0.34 times the diameter of the front wheel 10.

The rear rotation axis B has a distance L4 from the hinging axis F, comprised between 0.7 and 0.9 times the diameter of the front wheel 10, for example comprised between 0.75 and 0.85 times the diameter of the front wheel 10, preferably comprised between 0.78 and 0.83 times the diameter of the front wheel 10.

The hinging axis P has a distance L5 from the longitudinal axis of the beam 90, i.e. from the central axis T, comprised between 0.25 and 0.45 times the diameter of the front wheel 10, for example comprised between 0.32 and 0.42 times the diameter of the front wheel 10, preferably comprised between 0.34 and 0.4 times the diameter of the front wheel 10.

The hinging axis P has a distance L6 from the hinging axis F, comprised between 0.05 and 0.25 times the diameter of the front wheel 10, for example comprised between 0.1 and 0.2 times the diameter of the front wheel 10, preferably comprised between 0.12 and 0.17 times the diameter of the front wheel 10. The hinging axis P has a distance L7 from the rear rotation axis B, comprised between 0.6 and 0.8 times the diameter of the front wheel 10, for example comprised between 0.65 and 0.75 times the diameter of the front wheel 10.

Furthermore, the difference between the bicycle 1’ illustrated in figures xx and the bi cycle 1 lies in not being provided with slots 45,80 respectively in the steering column 35 and in the saddle post 70. However, it cannot be ruled out that such slots can be present in an embodiment (not illustrated).

Another difference between the bicycle T and the bicycle 1 lies in the fact that the bicycle 1’ may comprise a handlebar 40’ obtained in two segments hinged to a plate according to the same hinging axis, the plate being hinged to the steering column ac cording to an axis perpendicular to the steering axis, i.e. lying on a plane perpendicular to the steering axis.

A last difference between the bicycle 1’ and the bicycle 1 lies in the fact that the saddle post 70 is slidably associated to the rear triangle 55 according to a sliding axis parallel to a longitudinal axis of the saddle post.

The invention described above operates as follows.

In order to switch from the use configuration to the folded configuration of the bicycle 1 , the first step is to remove the handlebar 40, the saddle, and fold the pedals.

Next follows unlocking the front hinge 50 and the rear hinge 75 and respectively the steering column 35 and the saddle post 70 so that the corresponding slots 45,80 do not come into contact with the respective wheels 10,15.

Then the first hinge 1 15 and the second hinge 120 are unlocked and the first section 100 and the second section 105 are rotated with respect to the third section 1 10, posi tioning the front fork 20 at one side of the third section 1 10 and the rear triangle 55 at the opposite side of the third section 1 10 with respect to the one with respect to which the front fork 20 is arranged adjacent.

In particular, during this operation, the third section is located between the support of a pedal and the hub of the rear wheel, as shown in figure 7.

At this point, the bicycle 1 can be positioned in a bag V, for example of the business suitcase type, and transported using it.

In order to shift from the folded configuration to the use configuration, the folding oper ations outlined above are executed in the reverse order. The invention thus conceived is susceptible to numerous modifications and variants all falling within the inventive concept.

In addition, all details can be replaced by other technically equivalent elements.

Basically, the materials used as well as the shapes and contingent dimensions, may vary according to the needs without departing from the scope of protection of the claims that follow.