WO2020260973A1

WO2020260973A1 - Device for bicycle training

Info

Publication number: WO2020260973A1
Application number: PCT/IB2020/054818
Authority: WO
Inventors: Daniele BARTOLI
Original assignee: Stepgear. S.R.L.
Priority date: 2019-06-27
Filing date: 2020-05-21
Publication date: 2020-12-30
Also published as: EP3990132A1; IT201900010323A1

Abstract

A device for bicycle training, comprising: a support frame (10), predisposed to enable attachment of a bicycle frame; a fan flywheel (20), connected to the frame (10) and rotatable about a first axis (X) in an active rotation direction (A), which is provided with a plurality of radial blades (21); a transmission group (30), associated to the fan flywheel (20) and structured to connect to a bicycle transmission; each blade (21) has a front surface (22), facing in the rotation direction (A) of the fan flywheel (20), which is parallel to the first axis (X).

Description

DEVICE FOR BICYCLE TRAINING

DESCRIPTION

The present invention relates to a device for bicycle training.

The invention relates in particular to a device enabling bicycle training to take place while keeping the bicycle stationary. In substance, the device is predisposed to be connected to the frame of the bicycle, maintaining the bicycle stable in an erect position, and to be kinematically connected to the transmission, i.e. to the pedals activated by the user, thus producing a load that simulates the effort demanded during road riding.

A training device of the above-summarised type is described in publication US8147388. This device comprises a fan flywheel activated in rotation by the bicycle transmission. In substance, the fan flywheel is activated in rotation by the pedalling produced by the user.

The device known from the above-indicated publication has numerous drawbacks.

The fan flywheel is in fact provided with blades structured specifically to produce an aerodynamic thrust directed parallel to the axis of rotation of the fan flywheel. This is with the purpose of obtaining a consistent load that the user must overcome with her or his pedalling. Further, the aerodynamic thrust produced by the blades is opposed to a sliding of the fan flywheel exiting the axis of rotation thereof.

Owing to the conformation of the blades, the fan flywheel produces a very intense noise, extremely unpleasant for the user. Further, the air flow produced propagates to the surrounding environment, raising dust and other contaminants which might be present. A further drawback is given by the fact that the conformation of the blades does not in any case produce a dynamically uniform load. For this reason it is necessary to increase the moment of inertia of the fan flywheel, making it rather heavy and therefore making transport of the device more difficult. The aim of the present invention is to provide a device for bicycle training that enables obviating the drawbacks of the currently available devices.

An advantage of the device according to the present invention is to significantly reduce the noise produced, while providing a significant load that is very similar to the load produced by the road.

Another advantage of the device according to the present invention is that it contains the air flow produced.

A further advantage of the device according to the present invention is that of being very much lighter and more compact than the currently available devices, and of being usable both in connection with a traditional cycling vehicle and with a cycling vehicle for the disabled.

Further characteristics and advantages of the present invention will become more apparent in the following detailed description of an embodiment of the present invention, illustrated by way of non-limiting example in the attached figures, wherein:

- figure 1 shows an isometric view of the device according to the present invention, with a part of the casing removed;

- figure 2 shows a second isometric view of the device of figure 1 ;

- figure 3 shows the device of figure 2 with the casing intact;

- figure 4 shows the device of figure 3 in a compact configuration of non use;

- figure 5 shows the device according to the present invention in lateral view, associated to a bicycle.

The device for bicycle training according to the present invention comprises a support frame (10), predisposed to enable the resting of a bicycle to the ground surface and to support the frame (F) of a bicycle in an erect position. The attachment of the frame (F) takes place at a pin (more fully described in the following) which reproduces the features of the pin of the rear wheel of the bicycle. Figure 5 schematically illustrates the frame (F) of a traditional bicycle. The device according to the present invention is however suitable to enable connection to the frame of a special cycling vehicle, for example for the disabled or of another type.

The frame (10) comprises a pair of arms (11 ) which, overall, define a stable rest base on the ground surface. The arms (1 1 ) are foldable about a vertical rotation axis, between a compact position, in which they are flanked to the frame (10), and a rest position, visible in figures 1 and 2, in which they are moved away from the frame (10) forming therewith a rest base that is substantially triangular.

The device comprises a fan flywheel (20), connected to the frame (10) and rotatable about a first axis (X) in an active rotation direction (A). The fan flywheel (20) is provided with a plurality of radial blades (21 ). The fan flywheel (20) is associated to the bicycle transmission by means of a transmission group (30). In substance, the pedalling of the user sets the fan flywheel (20) in rotation via the transmission group (30).

Each blade (21 ) advantageously has a front surface (22), facing in the rotation direction (A) of the fan flywheel (20), which is parallel to the first axis (X). In other terms, the front surface (22) is conformed and arranged so as to push the air on a plane that is perpendicular to the first axis (X). The conformation of the front surfaces (22) is such as to produce an air flow directed on a perpendicular plane to the first axis (X), i.e. an air flow that is substantially free of components directed parallel to the first axis (X). Differently to what occurs in the known devices, the air flow produced by the rotation of the fan flywheel (20) is therefore not directed axially, i.e. is not directed parallel to the first axis (X), but is directed radially and/or tangentially to the fan flywheel (20), i.e. is directed on a perpendicular plane to the first axis (X). The flow produced by the fan flywheel according to the present invention is much more silent than that produced with the current devices. Notwithstanding this, the aerodynamic resistance produced by the fan flywheel, which is transmitted as a load to the user’s pedalling, is particularly effective, and the load produced is very similar to the load produced by road riding. In the illustrated embodiment, the front surface (22) has a curved conformation, with a concavity facing in the rotation direction (A). This configuration enables increasing the aerodynamic resistance produced by the fan flywheel (20) during rotation.

The device according to the present invention further comprises a casing (25) housing inside it the fan flywheel (20) and having a containing wall (26), arranged about the fan flywheel (20), which defines a ventilation space (S) that surrounds the blades (21 ).

As shown in figure 1 , the containing wall (26) is substantially parallel to the first axis (X). The containing wall (26) preferably has a curved extension about the first axis (X).

The containing wall (26) is preferably not concentric to the first axis (X). In substance, the ventilation space (S) has a width, measured along a radial direction with respect to the first axis (X), which is not constant, but varies in the rotation direction (A). In other terms, the containing wall (26) is conformed in such a way that the distance separating the end (23) of the blades (21 ) from the containing wall (26) is not constant, but varies in the rotation direction (A). In particular, this distance varies continuously from a minimum to a maximum and again to a minimum. In a possible embodiment, the ventilation space (S) is substantially spiral-shaped.

The conformation of the containing wall (26) described in the foregoing enables increasing the effect of the aerodynamic resistance produced by the fan flywheel (20).

The casing (25) further comprises two lateral walls (27), associated to the containing wall (26), which, together with the containing wall (26), completely enclose the fan flywheel (20), making the ventilation space (S) hermetically closed. The air flow produced by the fan flywheel (20) is thus contained inside the casing (25), resulting further silenced. The lateral walls (27) also enclose the transmission group (30), leaving outside only two portions of a pin predisposed to be associated to the rear fork of the frame (F) of the bicycle. One or more fixed fins (27) are preferably located in the ventilation space (S). Each fixed fin (27) contributes to increasing the aerodynamic load produced by the fan flywheel (20), so as to increase the resistance transmitted by the fan flywheel (20) to the user.

In the illustrated embodiment, preferred though not exclusive, two fixed fins (27) are present and located in a zone in which the width of the ventilation space (S) is greater. The fixed fins (27) have a flat conformation and are tangential to a concentric circumference to the first axis (X).

The transmission group (30) comprises a pulley (40), associated to the frame (10) rotatably about a second axis (Y) and connected in rotation to the fan flywheel (20). The second axis (Y) is parallel to the first axis (X). In the illustrated embodiment, the connection between the pulley (40) and the fan flywheel (20) is obtained by means of a belt (B), which can be flat or cogged. In a known way, an adjustable belt tensioning roller (R) can be located in contact with the unloading branch of the belt (B).

One or more cogged wheels are associated to the pulley (40) solidly with respect to the rotation about the second axis (Y). The cogged wheels are concentric to the second axis (Y). In substance, the cogged wheels take the place of the pinions normally associated to the rear wheel of the bicycle. The cogged wheels can thus be assembled in a box, using a cylindrical support (31 ), entirely alike the box normally mounted on the rear wheel of the bicycle.

The support (31 ) and the pulley (40) comprise a seat (32), concentric to the second axis (Y), structured to enable housing of a pin for the connection to the rear fork of the bicycle frame. For example, the pin is of a rapid-attachment type, or can be of the threaded through-type, as in the most recent solutions.

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Claims

1) A device for bicycle training, comprising:

a support frame (10), predisposed to enable attachment of a bicycle frame; a fan flywheel (20), connected to the frame (10) and rotatable about a first axis (X) in an active rotation direction (A), which is provided with a plurality of radial blades (21 );

a transmission group (30), associated to the fan flywheel (20) and structured to connect to a bicycle transmission;

characterised in that:

each blade (21 ) has a front surface (22), facing in the rotation direction (A) of the fan flywheel (20), which is parallel to the first axis (X).

2) The device according to claim 1 , wherein the front surface (22) has a curved conformation, with a concavity facing in the rotation direction (A).

3) The device according to claims 1 or 2, comprising a casing (25) housing inside it the fan flywheel (20) and having a containing wall (26), arranged about the fan flywheel (20), which defines a ventilation space (S) that surrounds the blades (21 ).

4) The device according to claim 3, comprising a casing (25) housing inside it the fan flywheel (20) and having a containing wall (26) that surrounds the fan flywheel (20) defining a space, a width of which, measured along a radial direction with respect to the first axis (X), increases in the rotation direction (A).

5) The device according to claim 3, comprising one or more fixed fins (27) located in the ventilation space (S).

6) The device according to claim 1 , wherein the transmission group (30) comprises a pulley (40), associated to the frame (10) rotatably about a second axis (Y) and connected in rotation to the fan flywheel (20).

7) The device according to claim 1 , wherein the transmission group (30) comprises one or more cogged wheels, structured to engage with a transmission chain of the bicycle.

8) The device according to claims 3 or 4, wherein each cogged wheel is concentric to the second axis (Y) and is solid in rotation with the pulley (40).

9) The device according to claim 5, wherein said one or more cogged wheels are associated to a support (31 ), concentric to the second axis (Y) and solid in rotation with the pulley (40).