DESCRIPTION

Technical field of the invention The present invention relates to a bicycle with improved frame.

Background

The bicycle is one of the most popular two-wheeled vehicles, usable both as a means of daily transport and as a means of practicing sports. The versatility of the two-wheeled vehicle means that bicycles can be used on different types of road surfaces, such as paved, asphalted, dirt roads, and with different slopes, from flat road sections to hilly and mountainous climbs and descents.

During a journey from one place to another, variations in slope and/or types of road surfaces can negatively affect the driver who has to exert physical effort in variable conditions. The changes in slope or the presence of obstacles, in particular, lead to sudden postural changes for the driver that can make the bicycle trip uncomfortable, up to physically stress the driver with consequent pain, joint inflammation, muscle overload, postural imbalances and others physical illness. Known bicycles have substantially rigid frames, provided with a front portion equipped with a handlebar and a rear portion provided with a seat for the driver, on which respective wheels are mounted. The front and rear portions are connected by a central portion integral therewith. The position of the driver’s body, during the journey, remains substantially integral with the connecting body. As the road surface changes, the vehicle frame adapts rigidly, inclining consistently with the slope of the road surface. As a result, the connecting body tilts and the driver’s body therewith. Thereby, the driver assumes negative positions, in which it is difficult both to maintain balance and to transmit the force necessary to move the vehicle. Suffice it to say that the typical seat lift which cyclists perform uphill. This change of position serves to compensate for the unfavourable slope of the climb, although involves a great consumption of energy and less control on the vehicle.

Furthermore, in traditional bicycles, the cyclist’s position is such that not all of the body weight is perpendicular to the thrust point, which reduces the power transmitted during pedalling.

Summary of the invention The technical problem posed and solved by the present invention is therefore to provide a bicycle with improved frame which allows to overcome the drawbacks above mentioned with reference to the prior art.

This problem is solved by a bicycle with improved frame according to claim 1 and flat thereby obtained according to the claim The invention further provides an improved frame for two-wheeled vehicles according to claim 11.

Preferred characteristics of the present invention are subject of the dependent claims.

The present invention provides several relevant advantages. The main advantage is that the improved frame can vary its set-up according to the slope of the road surface. In this way, the driver is facilitated to adopt a position favourable to maintaining balance and exerting greater thrust over the pedals. The improved frame, indeed, allows the driver to move his body mass perpendicular to the pedals, increasing the power and effectiveness of the thrust on the pedals.

The innovative frame of the bicycle allows the driver to maintain a favourable position during the level changes of the route. The driver, in fact, as the level of the road surface changes, remains with his body perpendicular to the thrust point. In this way, the whole weight is discharged on the thrust point, improving pedalling effectiveness by less effort. On average, it is possible to have 50% less than normal stresses on disconnected ground. This is due to the front-wheel going up and down without affecting the rear-wheel nor seat.

Another advantage is related to the assembly and transport of the bicycle. The improved frame, in fact, allows the disassembly of the bicycle into three pieces (front portion, rear portion and connecting body) that are easy to resemble. The ends of the connecting body, in particular, allow for quick, almost instant, assembly. Subsequently, the transport of the bicycle is further facilitated.

Other advantages, characteristics and methods of use of the present invention will become apparent from the following detailed description of several embodiments, presented by way of non-limiting examples.

Brief description of the drawings

Reference will be made to the figures of the attached drawings, in which:

^■ Figure 1 shows an axonometric view of a preferred embodiment of the bicycle devised according to the present invention;

^■ Figures 2, 3, 4 show a schematic view of the operation on different road surfaces of a preferred embodiment of the bicycle devised according to the present invention;

^■ Figure 5 shows a sectional side view of a detail of a first embodiment of the bicycle devised according to the present invention;

^■ Figure 6 shows an axonometric view of a detail of a first embodiment of the bicycle devised according to the present invention;

^■ Figure 7 shows a side sectional view of a detail of a second embodiment of the bicycle devised according to the present invention;

^■ Figures 8 and 9 show, respectively, an isometric view of a third and a fourth embodiment of the bicycle devised according to the present invention;

^■ Figure 10 shows an isometric view, partially exploded, of the bicycle of Figure 1.

The above Figures represent embodiments of the bicycle and/or frame, in schematic and/or simplified form, according to the present invention.

The thicknesses and curvatures shown in the figures introduced above are intended as purely illustrative, they are generally magnified and not necessarily shown in proportion.

Detailed description of preferred embodiments

Various embodiments and variants of the invention will be described below, and this with reference to the figures introduced above. Similar components are denoted in the various figures by the same numerical reference.

In the following detailed description, further embodiments and variants with respect to embodiments and variants already treated in the same description will be illustrated limitedly to the differences with what has already been stated. Furthermore, the different embodiments and variants described below are liable to be used in combination, whether compatible.

With reference initially to Figure 1, according to an embodiment of the invention a bicycle 1 is generally denoted by the reference number 1.

The bicycle 1 comprises a frame 2, a front-wheel 3 and a rear-wheel 4 mounted on the frame and configured to slide along a road surface 8. The bicycle is further provided with a motion transmission system, indicated by the number of reference 20, with toothed wheels connected by a chain and operated by pedals. The transmission system 20 illustrated is an example of a possible applicable transmission system, although the bicycle 1 can be provided with different transmission systems, for example having reels with several gear wheels, or other examples selected from those available in the state of art.

The frame 2 is advantageously provided with a front portion 6 mounting the front- wheel 3 and having a steering device 7, or otherwise named handlebar. The steering device 7 is connected to the front-wheel 3, so that the front-wheel 3 can be steered using the same steering device 7.

Conveniently, the front portion 6 can comprise a tubular body 15a, preferably shaped as a hollow tube.

The handlebar 7 is mounted onto the tubular body 15a and, in use, does not vary in height with respect to the tubular body itself. The handlebar 7 can rotate with respect to the tubular body 15a, with the axis of rotation substantially coinciding with the main development axis of the tubular body 15a, and is mounted in such a way as to maintain a constant height with respect to the tubular body itself, without lifting or lowering. Relative raising or lowering between the handlebar 7 and the tubular body 15a are prevented. The front portion 6 can be further provided with a fork 32 on which the front-wheel 3 is mounted.

The handlebar 7 can be connected to the fork 32 through connection means 31, for example by means of a rigid body 31 integral with the handlebar 7 and the fork 32. By rotating the handlebar 7, the rigid body 31 drags the fork 32 into rotation, steering the front -wheel 3.

The frame 2 is further advantageously provided with a rear portion 9 mounting the rear-wheel 4 and having a seat 10, otherwise named “saddle” or “riding”, suitable for a user or driver.

In particular, the rear portion 9, in use, has a rigid behaviour, i.e. it behaves like a rigid structure whose parts are integral with each other.

Conveniently, the rear portion 9 can comprise a tubular body 15b, preferably further shaped like a hollow tube.

The rear portion 9 can be usefully provided with seatstays 33 configured to mount the rear-wheel 4. The seatstays 33 are fixed integral with the tubular body 15b. In use, relative movements between the seat stays 33, the tubular body 15b and the seat 10 are thus prevented.

The frame 2, then, comprises a connecting body 11 is placed between the front portion 6 and the rear portion 9.

The connecting body 11 has a predefined inclination with respect to a substantially horizontal main direction D. The connecting body 11 illustrated in Figure 1 may have the conformation of a rigid rod that develops parallel to direction D, rather solutions other than the one illustrated are not excluded.

In any case, the connecting body 11 comprises a front end 12 inserted slidably in the front portion 6 and a rear end 13 inserted slidably in the rear portion 9. Thereby, relative sliding is allowed between the front portion 6, the connecting body 11 and the rear portion 9.

The configuration is such that as the slope of the road surface 8 varies, at least one of the front portion 6 and the rear portion 9 changes integrally in height by sliding with respect to the connecting body 11 , the latter maintaining the inclination unchanged with respect to the main direction D.

The term “integrally” means that the variation in height of the front portion 6 (or of the rear portion 9) affects every component part of the front portion 6 (or the rear portion 9), sliding between parts composing the same portion being prevented, as already described above. The overall configuration is such that the rear portion 9 does not rotate with respect to the rotation axis of the rear-wheel 4.

Preferably, the front end 12 can be inserted slidably into the front portion 6 between an upper front limit point, indicated in Figure 1 by the reference letter A’, and a lower front limit point indicated in Figure 1 with the reference letter A”.

The terms “upper” and “lower” refer to the position of frame 2 in use. A’ and A” are configured to prevent the front end 12 from scrolling beyond and, therefore, are end-of-stroke points beyond which the front portion itself cannot go. The tubular body 15a can be provided with at least one slot guide 18 along which the connecting body 11 can slide relatively with respect to the same tubular body 15a.

The front end 12 can be slidably inserted in the tubular body 15a, through the slot guide 18. By way of example, points A’ and A” can be of the type of closures of the section of the tubular body 15a, or they can be obstacles of another type, for example bars, caps, or welded flanges.

Advantageously, the tubular body 15a can be provided with sliding elements with constrained direction, for simplicity not shown in the figures. The sliding elements are configured to constrain the front end 12 from sliding along the main development direction of the tubular body itself, preventing relative rotations of the front end 12 with respect to the tubular body 15a. In a preferred but not exclusive embodiment, the constrained direction sliding elements can be linear ball bearings, or high sliding guides.

Usefully, the rear end 13 can be slidably inserted in the rear portion 9 between an upper rear limit point indicated in Figure 1 by the reference letter P’, and a lower rear limit point indicated in Figure 1 by the reference letter P”.

The tubular body 15b can be further provided with at least one slot guide 18 along which the connecting body 11 can slide relatively with respect to the tubular body 15b itself.

The front end 12 can be slidably inserted in the tubular body 15a, through the slot guide 18. By analogy to points A’ and A”, points P’ and P” can be of the type of closures of the section of the tubular body 15a, or they can be obstacles of another type, for example bars, or caps, or welded flanges.

As above, also the tubular body 15b can be provided with sliding elements with constrained direction, for simplicity not shown in the figures. The sliding elements are configured to constrain the rear end 13 from sliding along the main development direction of the tubular body itself, preventing relative rotations of the rear end 12 with respect to the tubular body 15b. In a preferred but not exclusive embodiment, the constrained direction sliding elements can be linear ball bearings, or high sliding guides.

The bicycle schematically illustrated in Figures 1, 2, 3 and 4, has a front portion 6 and a rear portion 9 each of which has a tubular body 15a, 15b in which the respective front end 12 and rear end 13 are inserted, with each tubular body 15a, 15b which is provided with a guide slot 18 along which the connecting body 11 can slide.

Preferably, the difference in height between the point P’ and the point P” can be greater than the difference in height between the point A’ and the point A”.

In particular, the point P” can have a height, evaluated with respect to a horizontal road surface (see Figures 1 and 2), lower than the point A”.

Thanks to the positioning of the points P’, P”, A’ and A” described above, the relative sliding between the rear portion 9 and the connecting body 11 is greater than the sliding between the connecting body 11 and the front portion 6. This facilitates the driver in finding the best thrusting position on the pedals, having a greater range right at the rear portion 9.

Advantageously, the frame 2 can comprise balancing means configured to prevent rotation of the rear portion 9 with respect to the axis of rotation of the rear-wheel 4. The balancing means, for simplicity not illustrated in the figures, can be of the type of force transmission systems, for example a spring system, able to balance the driver’s weight resting on the seat. Other systems known in the state of art are not excluded. Figures 2, 3 and 4 show in a simplified way the operation of the bicycle 1, in particular they show the variation of set-up in the frame 2 in relation to different slopes of the road surface 8.

In Figure 2, the road surface 8 is substantially horizontal and the frame 2 is in an “initial”, or “starting”, set-up, in which the connecting body 11 is at the front resting on the limit point A”, while at the rear the same is spaced from the limit point P”. The connecting body 11 remains rigidly floating.

Preferably, the difference in height between the point P” and the connecting body 11 can be comprised between 10 cm and 20 cm, preferably 15 cm. The difference in height between point P’ and the connecting body 11, however, can be comprised between 30 cm and 40 cm, preferably 30 cm.

Potentially, the connecting body 11 can achieve, with respect to the rear portion 9, a total range comprised between 40 cm and 60 cm, preferably about 45 cm. The difference in height between point A’ and point A”, on the other hand, is comprised between 10 cm and 20 cm, preferably 15 cm.

Potentially, the connecting body 11 can achieve, with respect to the front portion 6, a total range comprised between 10 cm and 20 cm, preferably about 15 cm. The dimensions provided above are purely illustrative, not binding and chosen to cover differences in the slope of the road surface of about 20%. When the slope of the road surface 8 changes, the frame 2 changes its set-up accordingly.

Figure 3 shows the bicycle 1 while traveling uphill on a road surface 8. Compared to the initial set-up described above, the frame 2 adopts another set-up, hereinafter referred to as “uphill set-up”.

In the transition from the initial set-up to the uphill set-up, the front portion 6 rises due to the variation of the road surface 8 level which tends to raise the front-wheel 3. As the slope increases, the front portion 6 rises progressively, dragging the connecting body 11. The connecting body 11 , consequently, rises progressively with respect to the rear portion 9, maintaining the inclination unchanged with respect to the main direction D. The connecting body 11 can slide until it reaches the limit point P’, as shown in Figure 3. This new uphill set-up allows the driver to exert a more effective thrust onto the pedals, with less effort and adapting his posture to climbing conditions. The driver’s posture thus adapted is comparable to the posture assumed in flat conditions, resulting in less muscular effort and greater thrust efficiency. For higher slopes, not illustrated, the connecting body 11 will begin to tilt, having a behaviour similar to that of the frames known in the state of art.

Figure 4 shows the bicycle 1 while travelling downhill a road surface 8. Compared to the initial set-up described above, the frame 2 adopts another set-up, hereinafter referred to as “downhill set-up”.

In the transition from the initial set-up to the downhill set-up, the front portion 6 descend due to the variation of the road surface 8 level, with the front-wheel 3 which tends to drop a level down following the variation of the road surface itself. As the slope increases, the front portion 6 progressively descends and the connecting body 11 therewith which rests on the limit point A”.

The connecting body 11 , consequently, progressively descends with respect to the rear portion 9, maintaining the inclination unchanged with respect to the main direction D. The connecting body 11 can slide until it reaches the limit point P”. At this point, the slope of the road surface 8 being further increased, the front portion 6 can continue to drop a level down, sliding with respect to the connecting body 11. The connecting body 11 , in fact, rests on the limit point P”, maintaining the inclination unchanged with respect to the main direction D which is substantially horizontal.

The front portion 6 can slide until the limit point A’ comes into contact with the connecting body 11 , as shown in Figure 4.

Also this new downhill set-up allows the driver to exert a more effective thrust on the pedals, with less effort and by adapting his posture to downhill conditions. The driver’s posture thus adapted is comparable to the posture assumed in flat conditions, resulting in better control of the vehicle. Even in such case, for higher slopes, not illustrated, the connecting body 11 will begin to tilt, with a behaviour similar to that of the frames known in the state of art. Usefully, the connecting body 11 can comprise a central portion 14 removably interposed between the front end 12 and the rear end 13. This innovative feature allows a fast disassembly of the frame 2, with the ends 12, 13 which can be left inserted in the respective front portion 6 and rear portion 9. The bicycle 1, therefore, can be disassembled into three pieces, which can be quickly assembled, without requiring to provide hinged elements in order to allow the frame to be closed.

The central portion 14 can preferably be provided with distal ends 19 configured to be coupled respectively to the front end 12 and to the rear end 13. According to a preferred embodiment, the connecting body 11 can comprise clamping elements 26 configured to lock the central portion 14 at the ends 12, 13. The clamping elements 26 can be sleeves wrapping the distal end 19 and the front end 12 (or area 13) around by locking them.

Technically equivalent solutions to those illustrated are not excluded, for example those in which the clamping elements are screwable ring nuts, or in which the profile of the ends 12 (or 13) and 19 is inclined and the clamping element 26 is counter-shaped to slide on such profile holding the ends 12 (or 13) and 19 coupled together by pressure.

With reference to Figure 5, at least one between the front end 12 and the rear end 13 can comprise a seatstay element 16 inserted in the respective tubular body 15a, 15b. In the present embodiment, the same considerations apply for both ends 12 and 13. By way of example, Figure 5 refers to the front end 12 slidably in the tubular body 15a, although the same considerations can be made for the rear end 13 slidable into the tubular body 15b. The slidably element 16 can have a substantially cylindrical shape and is inserted to size in the cylindrical body 15a such that it can slide. The cylindrical shape prevents the slidably element 16 from rotating with respect to the tubular body 15a, 15b. thereby, the angle between the connecting body 11 and the tubular bodies 15a, 15b remains substantially unchanged. Different solutions to the one illustrated are not excluded, in which the seatstay element 16 has a different conformation, for example in which the seatstay 16 has a crescent-shaped section, or having a cut substantially circular profile, i.e. having a linear section and a circular section. Further solutions in which the seatstay element 16 can slide externally to the cylindrical bodies 15a, 15b are not excluded.

In any case, the slidably element 16 allows the connecting body to slide with respect to the cylindrical bodies 15a, 15b, so that, at a variation in the slope of the ground, the two portions 6, 9 slide along a substantially vertical direction, and rotations of the connecting body 11 are prevented.

Advantageously, at least one between the front end 12 and the rear end 13 comprise at least one support element 17 fixed integrally to the seatstay element 16. The central portion 14 can be placed on the support element 17 and coupled thereto, for example by means of clamping elements 26.

Usefully, the support element 17 can protrude out of the slot guide 18. In this way the positioning of the central portion during assembly is simplified.

Preferably, the configuration is such that the central portion 14 can be rested on the support element 17 so as to form a prismatic coupling. This feature allows to further block the coupling between the central portion 14 and the front end 12 (or rear end 13), preventing the central portion 14 itself to slide with respect to the support element 17.

Usefully, the profile of the support element 17 can be grooved, with the distal end 19 having a counter-shaped profile correspondingly coupled to the support element 17.

With reference to Figures 5 and 6, the profile of the support element 17 can comprise a tooth 28, while the distal end 19 can comprise a corresponding recess 19 in which the tooth 28 can be inserted to size, forming a prismatic coupling. Solutions in which there is a plurality of teeth 28 and corresponding grooves 27 are not excluded, likewise geometrically different solutions are not excluded, although always configured to realize a prismatic coupling between the distal end 19 and the support element 17.

Advantageously, the connecting body 11 can be provided with at least one duct 24 configured for the passage of:

- transmission cables 22a, 22b, such as transmission cables for braking systems or transmission cables for shift systems; and/or - electric cables, for example connection cables between electricity supply systems (battery, dynamo, electric motors and other electrical devices) and user devices (lights, acoustic devices and other electronic devices optionally available on the bicycle).

With reference to figures 5 and 6, the duct 24 is obtained both on the central portion 14 and on the front end 12 (or rear end 13), defining two sections 24a and 24b which, in use, communicates with each other.

In this way, the frame 2 can be assembled/disassembled while maintaining the transmission cables 22a, 22b internal to the connecting body 11 . In this case, the transmission cables will be formed by separate segments, a first segment 22a at least partially inserted into the section 24a, and a second segment 22b at least partially inserted into the second section 24b.

By way of example, the two segments 22a and 22b are connected by means of a hook-and-slot system, illustrated in a simplified way in Figure 5 and indicated by the reference number 23. Different connection systems are not excluded, for example attachment systems rapid, or male/female systems.

Advantageously, the connecting body 11 can comprise electrical connection means 21 configured to electrically connect the central portion 14 and the front portion 12 (or the rear portion 13).

The electrical connection means 11 can comprise at least one pair of electrical contacts 29a, 29b or 30a, 30b. The electrical contacts can have a positive pole 29a or 30a placed on the support element 17, while the respective negative pole 29b or 30b is placed on the distal end 19. In use, the electrical contacts 29a, 29b or 30a, 30b are placed in contact such as to transfer electric current.

The electrical connection means 11 can be connected to the above electric cables or to an electric battery.

This feature is particularly useful whether the bicycle is configured to operate electrically.

In fact, bicycle 1 can be compatible for electrical operation, configured in such a way that can accommodate:

- a battery operatively connected to the electrical connection means 11 and/or to the above electrical cables; - an electric motor powered by the above battery by means of the electric connection means 11 and/or the above electric cables and configured to transfer motion to the rear-wheel 4.

The same considerations further apply whether the bicycle 1 is configured for traditional operation, without the use of an electric motor. In this case, the electrical connection means 11 can be used to establish a connection between electrical parts, allowing in any case a disassembly of the frame 2.

Figure 7 shows a detail of a second embodiment of bicycle 1. This second embodiment is simplified with respect to the one previously described and differs therefrom due to that fact that the connecting body 11 of frame 2 does not have a duct for the passage of transmission cables 22a, 22b and/or electric cables. In this case, in fact, the transmission cables 22a, 22b pass externally to the connecting body 11 , in particular externally to the distal end 19 and to the support element 17.

Figure 8 illustrates a third possible embodiment of the bicycle 1. This third embodiment illustrates a different shape of the frame 2, in particular of the fork 32 and of the connecting means 31. According to this variant embodiment, the connecting means 31 has transverse rods connected to the fork 32 at the front- wheel 3.

While maintaining the previously described advantages, the connecting body 11 of the bicycle of Figure 8 can remain on plain for a slope higher than the previously described embodiment. This is due to the fact that the different conformation of frame 2 allows a greater range for the connecting body 11.

Figure 9 shows a fourth possible embodiment of the bicycle 1. This fourth embodiment illustrates a different conformation of the frame 2. In particular, the connecting body 11 has a flared shape, compliant with the aesthetic prerogatives of a version intended for a gender market.

The central portion 14 has sections with different inclinations, although the main extension is always along a direction D, evaluated with respect to a flat, substantially horizontal bottom. The embodiments hitherto described show a bicycle 1 having an improved frame 2, in particular a frame 2 comprising a front portion 6, a rear portion 9 and a connecting body 11 as previously described. According to the present invention, the frame 2 above described can be adapted to all types of two-wheeled vehicles, for example motorcycles, motorcycles, scooters and other similar compatible vehicles.

Eventually, the present invention has been hitherto described with reference to preferred embodiments. It should be understood that other embodiments belonging to the same inventive core, as defined by the scope of protection of the claims below, may exist.