WO2022167983A1

WO2022167983A1 - Device for attaching a handlebar to a fork of a bicycle

Info

Publication number: WO2022167983A1
Application number: PCT/IB2022/050972
Authority: WO
Inventors: Giancarlo BIONDI
Original assignee: Bemax Italia S.R.L
Priority date: 2021-02-04
Filing date: 2022-02-04
Publication date: 2022-08-11

Abstract

Described is a device for attaching a handlebar of a bicycle to a fork (3) of the bicycle, the device comprising: an expansion member (10), elongate along an axis (A), including a contact surface (101) and movable between an expanded configuration, wherein the contact surface (101) is spaced from the axis by a first distance, and a contracted configuration, wherein the contact surface (101) is spaced from the axis by a second distance less than the first distance. The expansion member (10) is configured to be inserted inside the fork (3), with the contact surface (101 ) facing an inner surface of the fork (3). The device comprises a head (11), rigidly connected to the expansion member (10) at the first end (10A) and including a first connection zone (111), configured to constrain the rotation of the head (11) to the handlebar, and a second connection zone (112); a switching element, associated with the expansion member (10) for switching it between the expanded configuration and the contracted configuration and a locking element (13), connected to the head (11) at the second connection zone (112), to apply a locking force along the axis (A) and towards the expansion member (10).

Description

DESCRIPTION

DEVICE FOR ATTACHING A HANDLEBAR TO A FORK OF A BICYCLE

Technical field

The invention relates to a device for attaching a handlebar of a bicycle to a fork of the bicycle. Moreover, the invention also provides a bicycle and a method for attaching a handlebar of a bicycle to a fork of the bicycle.

Background art

In the sector of bicycles there are various prior art systems for connecting the handlebar to the fork. The fork of bicycles usually includes a hollow tubular element, which protrudes from the frame to be attached to the handlebar.

Aim of the invention

The handlebar comprises a hub for connecting it to the fork. The hollow tubular element of the fork is inserted inside the hub of the handlebar and the two parts are rotationally and axially constrained to each other.

The prior art involves the use of attachment devices which comprise external locking jaws and adjustment spacers. According to these solutions, the hub is inserted in the hollow tubular element and adjusted axially by interposing one or more spacers. Subsequently, the locking jaws (which in some cases can also be attached to the handlebars) are tightened in such a way as to apply a radial force on the hub and on the hollow tubular element from the outside towards the inside, applying a compressive force on the hollow tubular element.

Examples of devices for attaching a handlebar of a bicycle to a fork of the bicycle are provided in patent documents US2006/169009A1 , TW201704079A and US5647684A.

These solutions, as well as having considerable adjustment times, are also subject to breakages of the hollow tubular element which is not particularly resistant to compression, even more so in the last generation of bicycles, which are made almost always of carbon fibre.

The aim of the invention is to provide an attachment device and a method for attaching a handlebar of a bicycle to a fork of the bicycle, which overcome the above-mentioned drawbacks of the prior art.

Said aim is fully achieved by the attachment device and the method according to the invention as characterised in the appended claims.

According to an aspect of the invention, the invention provides a device for attaching a handlebar of a bicycle to a fork of the bicycle.

The device comprises a member, that is, an expansion member.

The expansion member is elongate along an axis between a first end and a second end. The expansion member includes a contact surface. The expansion member is movable between an expanded configuration, wherein the contact surface is spaced from the axis by a first distance, and a contracted configuration, wherein the contact surface is spaced from the axis by a second distance. Preferably, the second distance is less than the first distance. The expansion member is configured to be inserted inside the fork. Preferably, the expansion member is configured to be inserted in the fork with the contact surface facing an inner surface of the fork.

This makes it possible to apply a force from the inside of the fork towards the outside, thus applying a traction force, and not a compression force, on the fork and thus reducing the probability of breakage.

The device comprises a head. The head is rigidly connected to the expansion member, preferably at the first end. According to an embodiment, the head includes a first connection zone. The first connection zone is configured to constrain the rotation of the head to the handlebar. According to an embodiment, the head comprises a second connection zone.

The device comprises a switching element. The switching element is associated with the expansion member for switching it between the expanded configuration and the contracted configuration. According to an aspect of the invention, the device comprises a locking element. According to an embodiment, the locking element is an axial locking element.

The locking element is connected to the head. The locking element is connected to the head, at the second connection zone, to apply a locking force along the axis and towards the body.

The presence of the locking element allows the entire attachment device to be compacted axially, allowing discharge of the stresses on axial bearings positioned on the fork.

According to an embodiment, the head comprises a first surface, facing the body. The head comprises a second surface, opposite the first surface.

Preferably, the second connection zone is a threaded circular surface. Preferably, the second connection zone rises from the second surface of the head.

According to an embodiment, the locking element includes a ring nut. The ring nut comprises an outer cylindrical surface and an inner cylindrical surface. Preferably, the inner cylindrical surface is threaded. The inner cylindrical surface is configured to be coupled with the second connection zone of the head.

According to an embodiment, the first connection zone comprises a splined profile. The splined profile extends along an outer circumference of the head. The splined profile allows a shape coupling to be performed with a corresponding attachment profile of the handlebar.

According to an embodiment, the switching element is a threaded element. The threaded element rotates about the axis for switching the expansion element between the expanded configuration and the contracted configuration.

According to an embodiment, the expansion element, in its expanded configuration, is configured to apply a radial locking force, having at least one component oriented along a radial direction, perpendicular to the axis, and in a locking direction, coming out from the axis. The radial locking force is preferably oriented in the radial direction.

According to an aspect of the invention, the invention provides a bicycle. The bicycle comprises a fork. The fork comprises a hollow tubular element. The bicycle comprises a frame, rotating relative to the fork.

The bicycle comprises a handlebar. The handlebar comprises a connecting hub. The connecting hub is (at least partly) surrounding the hollow tubular element of the fork. The connecting hub comprises a coupling profile.

The bicycle comprises a device according to one or more of the features described in this document. In particular, the body of the device is inserted inside the hollow tubular element of the fork. Moreover, the first connection zone of the head is connected to the coupling profile of the handlebar.

According to an aspect of the invention, the invention provides a method for connecting a handlebar of a bicycle to a fork of the bicycle.

The method comprises a step of preparing an attachment device, comprising an expansion member, elongate along an axis, and a head. The method comprises a step of inserting a tubular element of the fork into a connecting hub of the handlebar.

The method comprises a step of inserting the expansion member, in a relative contracted configuration, inside the tubular element of the fork.

The method comprises a step of actuating a switching element.

The method comprises a step of switching the expansion member, in response to the actuation of the switching element, from the contracted configuration to an expanded configuration, in which a contact surface of the expansion member comes into contact with an inner surface of the tubular element of the fork.

The method comprises a locking step in which a locking element of the attachment device applies a locking force along the axis and towards the expansion member.

According to an embodiment, the switching step comprises a step of rotating the switching element, in response to which the expansion member moves between the expanded configuration and the contracted configuration.

According to an embodiment, during the step of inserting the expansion member, a first connection zone of the head couples with a coupling profile of the handlebar.

According to an embodiment, the locking step comprises a step of screwing a ring nut to a second connection zone of the head, preferably threaded and preferably rising from a surface of the head opposite the surface on which the expansion member is connected.

Brief description of the drawings

These and other features of the invention will become more apparent from the following detailed description of a preferred, non-limiting embodiment of it, with reference to the accompanying drawings, in which:

- Figure 1 illustrates a bicycle including an attachment device between a handlebar and a fork of the bicycle;

- Figure 2 is an exploded view of an attachment device between a handlebar and a fork of the bicycle of Figure 1 ;

- Figure 2A is a further exploded view of a detail of the exploded view of Figure 2;

- Figure 3 is a schematic cross-section of the device of Figure 2;

- Figures 4A and 4B are two cross-sections, according to different perspective views, of a part of the device of Figure 1 ;

- Figures 5A and 5B show two embodiments, corresponding to Figures 4A and 4B.

Detailed description of preferred embodiments of the invention

With reference to the accompanying drawings, the numeral 1 denotes a device for attaching a handlebar 2 to a fork 3 of a bicycle 100.

The device 1 comprises an expansion member 10. The expansion member 10 is configured to expand and contract between an expanded configuration and a contracted configuration. The expansion member 10 is elongate along an axis A between a first end 10A and a second end 10B.

The expansion member 10 preferably has a cylindrical shape. The expansion member 10 varies its external diameter as a result of its expansion, between a first value, in the expanded configuration, and a second value, in the contracted configuration, which is less than the first value.

The expansion member 10 includes a contact surface 101 , defined by the outer cylindrical surface of the member 10.

Said contact surface 101 is configured to come into contact with an inner cylindrical surface of the fork 3 and/or of the handlebar 2.

According to an embodiment, the device 1 comprises a head 11 . The head 11 is positioned at the first end 10A of the expansion member 10. The head 11 may be a separate element from the expansion member 10 and stably connected to it to be integral with it. Alternatively, the head 11 and the expansion member 10 are made as a single component (one piece); in this case, the expansion member 10 constitutes the part which can expand, varying its radial cross section (that is, its own overall size).

The head 11 is configured to be associated with the handlebar 2. The head 11 comprises a first connection zone 111. The head 11 comprises a second connection zone 112. The first connection zone 111 comprises a coupling profile (splined) 1111 , comprising one or more teeth, spaced along an outer circumference of the head 11 . Preferably, said one or more teeth are uniformly spaced along the outer circumference of the head 11 . According to an embodiment, the maximum diameter of said one or more teeth is greater than the radial distance between the contact surface 101 and the axis A.

The head 11 comprises a first surface 113, facing the expansion member 10 and perpendicular to the axis A. The head 11 comprises a second surface 114, opposite the first surface 113. According to an embodiment, the second connection zone 112 is positioned, located at the second surface 114. In particular, according to a preferred embodiment, the second connection zone 112 rises from the second surface 114 in a direction coming out of said second surface 114. According to an embodiment, the second connection zone 112 comprises a hollow cylindrical wall 1121 , which rises from the second surface 114. The hollow cylindrical wall 1121 comprises a threaded outer surface 1121 A.

The device 1 comprises a switching element 12. The switching element 12 is associated with the expansion member. The switching element 12 is configured for switching the expansion member 10 between the expanded configuration and the contracted configuration. According to an embodiment, the switching element is a threaded element 12, elongate along the axis A between a first end 12A and a second end 12B.

The first end 12A of the switching element 12 faces an inner cavity defined by the hollow cylindrical wall 1121 of the second connection zone 112. The first end 12A is the actuating end of the switching element 12 and is therefore accessible from the outside to be engaged to rotate the switching element 12 and define a switching from the expanded configuration to the contracted configuration.

The second end 12B of the switching element 12 is inserted inside the expansion member 10, to exert, in response to a rotation of the switching element 12, a radial force directed in a direction coming out of the axis A. In particular, the rotation of the switching element 12 in a first direction is configured to generate a radial force directed in a direction coming out of the axis A. According to an embodiment, the rotation of the switching element 12 in a second direction, opposite the first direction, is configured to generate a radial force directed in a direction entering the axis A. According to other embodiments, the expansion member is configured to return to the contracted position by the effect of one or more elastic elements, which, in the absence of the radial force determined by the switching element 12, return the expansion member 10 to the contracted configuration. The radial force coming out of the axis A is transmitted, by means of the contact surface 101 , to the inner cylindrical surface of the fork 3 and/or of the handlebar 2.

In response to the rotation of the switching element 12, the contact surface 101 comes into contact with the inner cylindrical surface of the fork 3, applying on the latter a radial force which determines a radial deformation of the fork. The fork 3 is radially deformed by the inner cylindrical surface of a connecting hub 21 of the handlebar. For this reason, in response to the rotation of the switching element 12 and with the expansion member 10 in the expanded configuration, the fork 3, the handlebar 2 and the expansion member 10 are constrained to each other to the rotation and to the axial translation (along the axis A) due to the friction effect between the contact surface 101 and the inner cylindrical surface 31 of the fork 3 and due to the friction effect between an outer cylindrical surface 32 of the fork 3 and an inner cylindrical surface of the handlebar 22. Said friction is obviously determined by a force normal to said surfaces, that is to say, by the radial force generated by the actuation of the switching element 12.

According to an embodiment, the device 1 comprises a locking element 13, preferably an axial locking element 13. The axial locking element 13 is preferably a ring nut 13, having the shape of a circular crown, with a predetermined thickness along the axis A.

The ring nut 13 comprises an inner cylindrical surface 131 , preferably threaded. The threaded cylindrical surface 131 is configured to be screwed with the thread of the threaded outer surface 1121 A of the second connection zone 112. According to an embodiment, the ring nut 13 is screwed until coming into contact with the second surface 114. This screwing makes it possible to apply an axial force on the unit comprising the device 1 , handlebar and fork, in such a way that the unit rests on axial bearings provided for the rotation of the fork 3, that is, for the rotation of the handlebar 2 during riding of the bicycle 100. According to an embodiment, the thickness along the axis A of the ring nut 13 is equal to the height of the cylindrical wall 1121. The ring nut 13 comprises one or more actuation holes 132, positioned on a screwing surface 133, perpendicular to the axis A and opposite the surface of the ring nut 13 which abuts on the second surface 114. Said one or more holes allow a screwing key to be fitted to it, which makes it possible to transmit a greater screwing torque than is possible by rotating the body of the ring nut 13.

The invention also provides a bicycle 100 including the attachment device 1 according to one or more of the features described in the invention.

Lastly, according to an aspect of the invention, the invention provides a method for attaching a handlebar 2 of a bicycle 100 to a fork 3 of the bicycle 100.

The method comprises a step of inserting a hub 21 for connecting the handlebar 2 in a tubular element of the fork 3, which protrudes along an axis A from the frame of the bicycle 100.

The method comprises a step of inserting an attachment device 1 , comprising a head 11 , an expansion member 10 and a switching element 12, inside the tubular element of the fork 3.

The method comprises a step of attaching a head 11 of the device 1 with a coupling profile 23 of the handlebar 2 in such a way as to constrain the rotation of the handlebar to the rotation of the head and, consequently, to the rotation of the device 1 .

The method comprises a step of applying a locking element 13, on the head 11 of the device 1 , for exerting an axial force along the axis A towards the frame of the bicycle 100.

The step of applying the locking element 13 is preferably a step of screwing a ring nut 13 to a second connection zone 112 (to an outer threaded surface 1121 A) of the head 11 .

The method comprises a step of actuating the switching element 12, for switching the expansion member 10 between a contracted configuration and an expanded configuration. The step of actuating the switching element 12 comprises a step of rotating the switching element 12.

The method comprises a step of applying a radial force coming from the axis A on an inner surface 31 of the fork 3 by the expansion member, in response to the rotation of the switching element.

The method also comprises a step of adjusting the height of the handlebar 2 relative to the fork 3. During the adjustment step, the switching element is actuated to bring the expansion member from the expanded configuration to the contracted configuration. The ring nut 13 is unscrewed from the second connection zone 112. The handlebar is raised or lowered manually relative to the fork 3 along the axis A. Subsequently, the switching element 12 is screwed again to switch the expansion member from the contracted configuration to the expanded configuration, in such a way as to again render the device 1 , the handlebar 2 and the fork 3 integral with each other. Lastly, the ring nut 13 is again screwed to the second connection zone 112.

Claims

1. A device (1 ) for attaching a handlebar (2) of a bicycle to a fork (3) of the bicycle (100), the device comprising:

- an expansion member (10), elongate along an axis (A) between a first end (10A) and a second end (10B) and including a contact surface (101 ), the expansion member (10) being movable between an expanded configuration, wherein the contact surface (101 ) is spaced from the axis by a first distance, and a contracted configuration, wherein the contact surface (101 ) is spaced from the axis by a second distance which is smaller than the first distance, the expansion member (10) being configured to be inserted inside the fork (3), with the contact surface (101 ) facing an inner surface (31 ) of the fork (3);

- a head (11 ), rigidly connected to the expansion member (10) at the first end (10A) and including a first connection zone (111 ), configured to constraining the rotation of the head (11 ) to the handlebar, and a second connection zone (112);

- a switching element (12), associated with the expansion member (10) for switching it between the expanded configuration and the contracted configuration, characterised in that it comprises a locking element (13), connected to the head (11 ) at the second connection zone (112), to apply a locking force along the axis (A) and towards the expansion member (10).

2. The device (1 ) according to claim 1 , wherein the head (11 ) comprises a first surface (113), facing the member (10), and a second surface (114), opposite the first surface (113), and wherein the second connection zone (112) is a threaded circular surface, rising from the second surface (114) of the head (11 ).

3. The device (1 ) according to claim 2, wherein the locking element (13) includes a ring nut, comprising an outer cylindrical surface and an inner cylindrical surface (131 ), threaded and configured to be coupled with the second connection zone (112) of the head (11 ).

4. The device (1 ) according to any one of the preceding claims, wherein the first connection zone (111 ) of the head (11 ) comprises a splined profile (1111 ), which extends along an outer circumference of the head (11 ), to perform a shape coupling with a corresponding coupling profile (23) of the handlebar (2).

5. The device (1 ) according to any one of the preceding claims, wherein the switching element (12) is a threaded element, and wherein the threaded element rotates about the axis for switching the expansion member (10) between the expanded configuration and the contracted configuration.

6. The device (1 ) according to any one of the preceding claims, wherein the expansion member (10), in its expanded configuration, is designed to apply a radial locking force, oriented along a radial direction (R), perpendicular to the axis (A), and in a locking direction, coming out from the axis (A).

7. The device (1 ) according to any one of the preceding claims, wherein the first connection zone (111 ) of the head (11 ) is configured for coupling to a coupling profile (21 ) of the handlebar (2) by means of a shape coupling.

8. A bicycle (100) comprising:

- a fork (3), comprising a hollow tubular element;

- a handlebar (2), including a connecting hub (21 ), at least partly surrounding the hollow tubular element of the fork (3) and comprising a coupling profile (23); - a device (1 ) according to any one of the preceding claims, wherein the expansion member (10) is inserted inside the hollow tubular element of the fork (3) and wherein the first connection zone (111 ) of the head (11 ) is connected to the coupling profile (23) of the handlebar (2).

9. A method for connecting a handlebar (2) of a bicycle (100) to a fork (3) of the bicycle (100), the method comprising the following steps:

- preparing an attachment device (1 ), comprising an expansion member (10), elongate along an axis (A), and a head (11 );

- inserting a tubular element of the fork (3) into a connecting hub (21 ) of the handlebar (2);

- inserting the expansion member (10), in a relative contracted configuration, inside the tubular element of the fork (3);

- actuating a switching element (12) of the device (1 );

- switching the expansion member (10), in response to the actuation of the switching element (12), from the contracted configuration to an expanded configuration, in which a contact surface (101 ) of the expansion member (10) comes into contact with an inner surface (31 ) of the tubular element of the fork (3), characterised in that it comprises a locking step, in which a locking element (13) of the attachment device (1 ) applies a locking force along the axis (A) and towards the expansion member (10).

10. The method according to claim 9, wherein the switching step comprises a step of rotating the switching element (12), in response to which the expansion member (10) moves between the expanded configuration and the contracted configuration.

11. The method according to claim 9 or 10, wherein, during the step of inserting the expansion member (10), a first connection zone (111 ) of the head (11 ) couples with a coupling profile (21 ) of the handlebar (2).

12. The method according to any one of claims 9 to 11 , wherein the locking step comprises a step of screwing a ring nut (13) to a second connection zone (112) of the head (11 ), threaded and rising from a surface (114) of the head (11 ) opposite the surface (113) on which the expansion member (10) is connected.

13. The method according to any one of claims 9 to 12, wherein the head (11 ) includes a first connection zone (111 ), configured to constrain the rotation of the head (11 ) to the handlebar, and a second connection zone (112), and wherein, during the locking step, an inner threaded cylindrical surface (131 ) of the locking element (13) is coupled to the second connection zone (112) of the head (11 ).

14. The method according to claim 13, wherein the head (11 ) comprises a first surface (113), facing the member (10), and a second surface (114), opposite the first surface (113), and wherein the second connection zone (112) rises from the second surface (114) of the head (11 ).

15. The method according to any one of claims 9 to 14, wherein the head (11 ) comprises a splined profile (1111 ), which extends along an outer circumference of the head (11 ), wherein the method comprises a shape coupling between the splined profile (1111 ) of the head and a corresponding coupling profile (23) of the handlebar (2).