EP0980327A1

EP0980327A1 - Driving device for a crank gear machine

Info

Publication number: EP0980327A1
Application number: EP97945930A
Authority: EP
Inventors: Hubert Mourer
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-11-15
Filing date: 1997-11-14
Publication date: 2000-02-23
Also published as: WO1998022333A1

Abstract

The invention concerns a driving device for a machine comprising a crank gear (3) actuated by a user's force, operating on the pedals (4) arranged at the free ends of two pedal cranks (5) integral with said crank gear (3), the latter being connected to a driving pinion (6) of a main wheel by means of a free intermediate gear wheel (8) comprising at least two toothed stages (8a, 8b) one of which (8b) is connected to the crank gear (3) and the other (8a) to a driving pinion (6) by any connecting means. The invention is characterised in that the intermediate gear wheel (8) includes at least one first toothed stage (8b) connected to the standard crank gear (3) and the diameter of which is not greater than that of said crank gear (3) and a second toothed stage (8a) connected to the driving pinion (6) of the wheel (7) and the diameter of which is greater than that of said crank gear (3), so as to obtain a velocity gain of the machine for a given torque supplied by the user.

Description

DEVICE FOR DRIVING A PEDAL MACHINE

The present invention relates to a device for driving a machine of the type comprising a crankset actuated in rotation by the force of a user, acting on pedals disposed at the free ends of two cranks integral with said crankset.

The invention will find a particularly advantageous application in the field of cycles, bicycles, mopeds and mopeds in particular, and more generally in the field of machines actuated by human effort and in particular by the legs. Usually, a cycle crankset cannot make it possible to exceed the speed resulting from the ratio of the diameters existing between that of the crankset and that of the rear wheel sprocket which drives it via a transmission chain. On a conventional bicycle, the largest difference in diameter is that existing between the largest of the pedals stages and the smallest pinion of the rear wheel to be driven, in general about 20 cm in diameter for the first and 5 cm for the second, which for a pedal turn of the pedal gives a maximum of four turns of the rear wheel.

It has often been imagined devices allowing a less effort on the pedals of a bicycle with equal development, compared to a conventional bicycle in order therefore to obtain an increase in torque.

To do this, it is proposed and described in French patent application no. 2,670,174, as in French patents n ° 898,069, 926,528 and 968,750, to connect the crankset to the drive pinion of the driving wheel of the bicycle, by means of a free plate arranged between the two aforementioned elements and comprising at least two toothed stages, one of which is connected to the crankset and the other to the drive sprocket, by chains.

We realize from the study of these documents that if the stage of the intermediate plate connected to the crankset can be of a diameter smaller than this, we note on the other hand that the stage of the same intermediate plate connected to the pinion d drive is never larger than said crankset, in order to obtain an increase in speed for a given torque, if necessary by considerably reducing the diameter of the crankset as for example, in the French patent of invention n ° 898.069 or even German patent n ° DE-39.08.385, but which are therefore no longer conventional pedal boards on the market and which require special manufacturing.

The object of the present invention consists mainly in offering the possibility of increasing the speed of the machine up to doubling it and even more, while respecting the dimensions of the frame of the bicycle, as well as by using a conventional crankset.

It will be generally accepted that according to the current bicycle market, a conventional crankset is a crankset whose upper diameter stage has a number of teeth between 42 and 52 for a diameter generally from 170 mm to 200 mm .

In order to achieve the above object, the invention relates to a device for driving a machine comprising a conventional crankset actuated in rotation by the force of a user, acting on pedals disposed at the free ends of two cranks integral with said crankset, the latter being connected to a drive pinion of a driving wheel via a free intermediate plate comprising at least two toothed stages, one of which is connected to the crankset and the other to the drive pinion by any connecting means, characterized in that the intermediate plate comprises at least one first toothed stage in connection with a conventional crankset and whose diameter is equal to or smaller than this and a second toothed stage in connection with the wheel drive pinion and whose diameter is greater than that of said crankset, so as to obtain a gain in machine speed for a given torque supplied by the user.

According to another characteristic of the invention, the intermediate plate comprises at least three toothed stages of different diameters staggering concentrically from the inside towards the outside from an axis of free rotation, at least two internal stages being reserved to the connection with the conventional crankset which is effected optionally by means of a derailleur (not shown) and having diameters respectively smaller or equal to said chainring, while at least one external stage is in permanent connection with the drive pinion and is of a larger diameter than that of said bottom bracket. According to another characteristic of the invention, the intermediate plate comprises at least three toothed stages of different diameters ranging concentrically from the inside to the outside at from a free axis of rotation, at least one internal stage being in connection with the conventional crankset and having a diameter smaller or equal to that of the latter, while at least two external stages are reserved for the connection with the drive pinion being carried out as desired by means of a derailleur (not shown) and having diameters larger than that of the conventional crankset. The present invention also relates to the characteristics which will emerge during the description which follows and which should be considered in isolation or according to all their possible technical combinations. This description given by way of nonlimiting example will make it easier to understand how the invention can be implemented with reference to the attached drawings in which:

- Figures 1, 1A are side views of a bicycle comprising the drive device according to the invention according to a first and a second embodiment;

- Figures 2, 2A and 3, 3A are side views showing alternative embodiments of a crankset and an intermediate drive plate;

- Figures 4, 4A are side views of a bicycle comprising a drive device whose intermediate plate constitutes an alternative embodiment; - Figures 5, 5A are side views of a pedal and an intermediate plate according to Figures 4, 4A; - Figures 6, 6A are side views of a bicycle comprising a drive device whose intermediate plate constitutes an alternative embodiment of the invention; - Figures 7, 7A are side views of a bicycle comprising a drive device whose intermediate plate constitutes an alternative embodiment of the invention;

- Figures 8, 8A are schematic side views of a bicycle comprising a drive device according to an alternative embodiment of the invention;

- Figures 9, 9A are side views of a crankset and an intermediate plate according to an alternative embodiment of Figure 8, 8A;

- Figure 10 is a side view of a bicycle comprising a drive device according to another alternative embodiment of the invention; - Figure 11 is a side view of a bicycle comprising a drive device according to an alternative embodiment of the invention;

- Figure 12 is a side view of a crankset and an intermediate plate according to Figure 11; - Figure 13 is a side view of a bicycle comprising a drive device whose intermediate plate constitutes an alternative embodiment of the invention;

FIG. 14 is a side view of a crankset and an intermediate plate according to FIG. 13.

The bicycle 1 designated as a whole in FIG. 1 is cited by way of example of application of the invention. It will not be described in detail since it is known per se.

The generally designated drive device 2 comprises a conventional crankset 3 actuated in rotation by the force of a user, acting on pedals 4 arranged at the free ends of two cranks 5 integral with said crankset 3. The latter is connected to a pinion driving a driving wheel 7 of the bicycle 1, by means of a free intermediate plate 8 comprising at least two toothed stages 8a, 8b, one of which 8b is connected to the conventional crankset 3 and the other 8a to the drive pinion 6, thanks to connection means.

The means of connection of one of the stages 8b of the intermediate plate 8 with the conventional crankset 3 on the one hand, and the means of connection of another stage 8a of the same intermediate plate 8 with the drive pinion 6 of the wheel 7 on the other hand, are constituted by two chains 9 and 10 independent of each other.

The chains 9 and 10 constituting the connecting means between the intermediate plate 8 and the crankset 3 on the one hand, and the drive pinion 6 on the other hand, form strands facing each other. According to a variant shown in FIG. 1A, the chains 9 and 10 constituting the connection means between the intermediate plate 8 and the crankset 3 on the one hand, and the drive pinion 6 on the other hand, form crossing strands , so as to obtain an action of said chains 9 and 10 on a greater number of teeth of the three elements 3, 8, 6 in presence.

According to the basic principle of the invention, the intermediate plate 8 comprises a first toothed stage 8b, in connection with the conventional crankset 3, and whose diameter Dl is equal to or smaller than that D2 of said crankset 3, and a second toothed stage 8a, in connection with the drive pinion 6 of the wheel 7, and of which the diameter D3 is greater than that D2 of said bottom bracket 3, so as to obtain a gain in speed of the machine for a given torque supplied by the user.

Still according to the present exemplary embodiment, it is indicated by way of nonlimiting illustration that the diameter of the stage 8a of the intermediate plate 8 is of a diameter D3 or D3 'equal to 30 cm, and that the second stage 8b is with a diameter Dl equal to 20 cm in connection, via the chain 9, with the bottom bracket 3 which is of a diameter D2 equal to 20 cm also, in the present example. The drive pinion 6 in connection with the stage 8a of the intermediate plate 8, via the chain 10, is in turn of a diameter of 5 cm. The profile views of FIGS. 3 or 3A represent drive devices 2A essentially differ from the previous one in that the drive of the stage 8b of the chainring 8 is in direct engagement with the crankset 3. The embodiments shown in the figures 4, 5 or 4A, 5A differ essentially from the previous ones in that the intermediate plate 8 comprises three toothed stages 8b, 8a, 8c of different diameters staggering concentrically from the inside to the outside from an axis of rotation free 11, the internal stage 8b being in permanent connection with the conventional plate 3 and having a diameter Dl equal to that D2 of the latter, while the central 8a and external 8c stages are reserved for the connection with the drive pinion 6 being carried out as desired by means of a derailleur (not shown) and having diameters D3 and D4 larger than that of D2 of the conventional plate 3 (Figures 5 or 5A).

By way of example also, the diameters D1 and D2, respectively of the stage 8b of the intermediate plate 8 and D2 of the bottom bracket 3 have a diameter of approximately 20 cm, while the stage 8a and 8c of the same intermediate plate 8 have diameters D3 and D4, approximately 30 and 40 cm respectively.

According to the example of FIGS. 6, 6A, the drive device differs in that the intermediate plate 8 comprises three stages 8b, 8e, 8f whose diameter of the first 8b is always equal to that of the bottom bracket 3, but whose diameters 8e and 8f have smaller diameters. The stage 8a of the same plate 8 remains of a diameter D3 = 30 cm unchanged. The passage from one to the other of the stages 8b, 8e, 8f is effected by means of a derailleur (not shown). The exemplary embodiment according to FIG. 7, 7A differs from that of FIG. 6, 6A in that it further comprises an additional stage 8c, with a diameter D4 = 40 cm identical to that of FIG. 4, 4A , in order to offer with stage 8a a possibility of additional relationship with the rear pinion 6 via the chain 10 and a derailleur (not shown). In fact, in the embodiments shown in Figures 6, 6A and 7, 7A above, the intermediate plate 8 respectively comprises four or five toothed stages 8a, 8b, 8c, 8e, 8f of diameters different staggered concentrically from the inside to the outside from a free axis of rotation 11, the interior stages 8b, 8e, 8f being reserved for the connection with the conventional crankset 3 being carried out as desired by the intermediate of a derailleur (not shown) and having diameters respectively smaller or equal to said crankset 3, while the outer stages 8c and 8a which are in connection with the drive pinion 6, are of a diameter greater than that of said pedal unit 3.

According to the example of FIGS. 8, 8A, the connection of one of the stages 8b of the intermediate plate 8 with the crankset 3 is effected by direct engagement of the teeth of one 8b with the teeth of the other 3, then that the connection of another stage 8a of the same intermediate plate 8 with the drive pinion 6 of the shaft 7 takes place via a chain 10. Of course, although not shown, the connections of one of the stages 8b of the intermediate plate 8 with the crankset 3 and of another stage 8a of the same crankset 3 with the drive pinion 6 of the wheel 7 can be carried out in both cases by direct engagement of the teeth of the stages 8b, 8a of the intermediate plate 8, respectively with those of the crankset 3 and those of the pinion 6.

According to another exemplary embodiment illustrated by FIG. 9, 9A, this drive device essentially differs from that of FIG. 8, 8A in that the chain 10 in connection with the rear drive pinion 6 can, by the via a derailleur (not shown), and according to the wishes of the user, be driven, either by a stage 8c of the plate 8 or another lower stage 8a of the same plate 8, the internal stage 8b being itself, as in the example of FIG. 8, 8A, in direct engagement with the crankset conventional 3. In the latter case, the bottom bracket 3 has a diameter of at least 20 cm and meshes with the stage 8b of the plate 8 with a diameter of 20 cm, while the stage 8a of the same plate and 8c are respectively 30 and 40 cm in diameter. According to all the cases of FIGS. 1 to 9 above, the intermediate plate 8 is fixed on a part 13 of the frame of the bicycle 1, substantially in the vertical axis of the conventional crankset 3.

On the other hand, according to all the cases of FIGS. 1A to 9A, the intermediate plate 8 is fixed on a rear part 13 of the frame of the bicycle 1, on an axis XX 'starting from the center of the conventional crankset 3 and forming an angle α with respect to at its vertical axis YY ', said axis XX' extending towards the rear of said bicycle 1.

According to the example of Figures 10 ex 14, the intermediate plate 8 is also arranged on an axis XX 'starting from the center of the conventional pedal unit 3 and forming an angle α relative to its vertical axis YY', said axis XX 'extending towards the rear of said bicycle 1.

According to these latter embodiments, the connection of one of the stages 8b of the intermediate plate 8 with the crankset 3 takes place via a chain 9, while the connection of another stage 8a of the same plate intermediate 8 with the drive pinion 6 of the wheel 7 is effected by grip direct teeth of one 8a with teeth of the other

6.

It can be provided according to a variant not shown that the connections of one of the stages 8b of the intermediate plate 8 with the crankset 3 and another stage 8a of the same plate 3 with the drive pinion 6 of the wheel 7, are made in both cases by direct engagement of the teeth of stages 8a, 8b of the intermediate plate 8, respectively with those of the crankset 3 and with those of the pinion 6.

One could also imagine that the connection by direct engagement of the teeth of one of the stages 8a, 8b of the intermediate plate 8 with those of the drive pinion 6 of the wheel 7 is effected by teeth provided on their respective outer periphery.

In fact, according to the exemplary embodiments represented in FIGS. 10, 11 and 12, the connection by direct engagement of the teeth of one of the stages 8a of the intermediate plate 8 with those of the drive pinion 6 of the wheel 7 s' made by an internal peripheral toothing of a hollow crown 12 constituting said plate 8, capable of cooperating with the external peripheral toothing of the drive pinion 6 which is housed like a satellite inside said crown 12 constituting the tray 8.

According to these same examples of FIGS. 10, 11 and 12, the stages 8a, 8b of the intermediate plate 8 are concentric. In all cases, the intermediate plate 8 is centered relative to the axis of rotation of the latter and is fixed freely on a fixed rear part 13 of the frame of the bicycle 1. As the figure shows particularly well

11, the intermediate plate 8 comprises at least three toothed stages of different diameters staggering concentrically from the inside to the outside from a free axis of rotation 11, at least two internal stages 8b, 8e being reserved for the connection with the conventional crankset 3 being carried out as desired by means of a derailleur (not shown) and having diameters respectively smaller or equal to said chainring 3, while at least one external stage 8a is in permanent connection with the drive pinion 6 and is of a larger diameter than that of said bottom bracket 3.

According to an embodiment shown in Figures 13 and 14, it differs essentially from the previous ones in that one of the stages 8b of the intermediate plate 8 is eccentric with respect to the axis of rotation of the latter and is freely mounted on a part of the frame, said stage 8b further comprising an external toothing in connection, by chain or direct drive, with the conventional crankset 3, and an internal toothing in direct engagement with a stage 8c, concentric with stage 8a of said intermediate plate 8, which stage 8a has an internal toothing in direct engagement with the external toothing of a drive pinion 6 of the wheel 7.

The operation of the various drive devices which have just been described is as follows. When a cyclist makes a pedal turn with a conventional diameter of approximately 20 cm, he drives the intermediate plate situated above it by means of the connecting chain 9. If it is assumed that the stage of the plate 8 in connection with the pedal 3 is of the same diameter, they will rotate at the same speed. On the other hand, the second stage of the intermediate plate, with a larger diameter than that of the crankset, will cause the drive pinion with which it is connected and therefore the wheel, to make a number of turns corresponding to the number for which its diameter is greater, multiplied by the number of turns to which it is itself driven by the pedal, acting through the small stage.

Thus, for example, if the second stage of the intermediate plate is 30 cm, and the first stage is 20 cm, that is to say identical to the diameter of the crankset, with a rear sprocket of 5 cm, a pedal turn according to the invention will be obtained, 30: 5 = 6 wheel turns instead of 20: 5 = 4 wheel turns, traditionally.

The desired effect can be increased as illustrated for example by FIG. 7, 7A in which the crankset, conventionally having a diameter of 20 cm, drives by chain 9 the smallest stage 8f with a diameter of 5 cm from the intermediate plate 8 , the ratio will be 20: 5 = 4. If, on the other hand, the largest stage 8c of the same plate 8 has a diameter of 60 cm and drives a rear pinion 6 conventionally with a diameter of 5 cm, the ratio will be of 60: 5 = 12 multiplied by the number of revolutions to which it is itself driven by the crankset acting through the small 5 cm stage, which gives 4 x 12 = 48 rotations of the rear wheel for one revolution pedal. The reduction ratio is therefore twelve times greater (48: 4 = 12) than the reduction ratio of the bicycle. traditional which is four rotations of the rear wheel for one pedal turn (20: 5 = 4).

Of course, from this reasoning, any other ratio can be obtained by carrying out combinations of ratios with intermediate or greater diameters.

The advantage will thus be to obtain a speed of the bicycle considerably higher compared to the conventional bicycle for an effort of the cyclist identical or hardly higher.

According to the embodiments described above, the stages of the intermediate plate 8 are always concentric.

The invention makes it possible to change the speed of the traditional bicycle to a speed which is not only doubled, but almost tenfold, at the cost of a muscular effort within the reach of everyone.

Claims

1. Device for driving a machine of the type comprising a crankset (3) actuated in rotation by the force of a user, acting on pedals (4) disposed at the free ends of two cranks (5) integral with said crankset ( 3), the latter being connected to a drive pinion (6) of a driving wheel by means of a free intermediate plate (8) comprising at least two toothed stages (8a, 8b), one of which (8b) is connected to the pedal (3) and the other (8a) to the drive pinion (6) by any connecting means, characterized in that the intermediate plate (8) has at least one first toothed stage (8b ) in connection with a conventional crankset (3) and whose diameter (Dl) is equal to or smaller than that (D2) of said crankset (3) and a second toothed stage (8a) in connection with the drive pinion (6 ) of the wheel (7) and whose diameter (D3, D3 ') is greater than that (D2) of said bottom bracket (3), so as to obtain a gain in speed of the machine for a given torque supplied by the user.

2. Device according to claim 1, characterized in that, being a bicycle, said intermediate plate (8) is disposed substantially in the vertical axis of the conventional pedal (3).

3. Device according to claim 1, characterized in that, being a bicycle, said intermediate plate (8) is arranged on an axis (XX ') starting from the center of the conventional crankset (3) and forming an angle ( α) relative to its vertical axis (YY '), said axis (XX') extending towards the rear of said bicycle (1).

4. Device according to one of claims 1, 2 or 3, characterized in that the intermediate plate (8) comprises at least three toothed stages of different diameters staggered concentrically from the inside to the outside from a free axis of rotation (11), at least two internal stages (8b, 8e, 8f) being reserved for the connection with the conventional crankset (3) being carried out optionally via a derailleur (not shown) and having diameters respectively smaller or equal to said plate (3), while at least one outer stage (8a) is in permanent connection with the drive pinion (6) and is of a larger diameter than that of said crankset (3).

5. Device according to one of claims 1, 2 or 3, characterized in that the intermediate plate (8) comprises at least three toothed stages of different diameters staggered concentrically from the inside to the outside from a free axis of rotation (11), at least one internal stage (8b) being in connection with the conventional crankset (3) and having a diameter smaller or equal to that of the latter, while at least two external stages ( 8c, 8a) are reserved for connection with the drive pinion (6) being carried out as desired via a derailleur (not shown) and having diameters larger than that of the conventional crankset (3).

6. Device according to one of claims 1 to 5, characterized in that the connecting means of one of the stages (8b) of the intermediate plate (8) with the conventional crankset (3) on the one hand, and the connecting means of another stage (8a, 8c) of the same plate intermediate (8) with the drive pinion (6) of the wheel (7) on the other hand, are constituted by two chains (9) and (10) independent of each other.

7. Device according to claim 6, characterized in that the chains (9) and (10) constituting the connecting means between the intermediate plate (8) and the crankset (3) on the one hand, and the drive pinion (6) on the other hand, form strands facing each other. 8. Device according to claim 6, characterized in that the chains (9) and (10) constituting the connecting means between the intermediate plate (8) and the crankset (3) on the one hand, and the drive pinion (6) on the other hand, form crossing strands, so as to obtain an action of said chains (9) and (10) on a greater number of teeth of the three elements (3,

8, 6) in the presence.

9. Device according to one of claims 1 to 5, characterized in that the connection of one of the stages (8b) of the intermediate plate (8) with the crankset (3) is effected by direct engagement of the teeth of the 'one (8b) with the teeth of the other (3), while the connection of another stage (8a, 8c) of the same intermediate plate (8) with the drive pinion (6) of the shaft (7) takes place via a chain (10).

10. Device according to one of claims 1 to 5, characterized in that the connections of one of the stages (8b) of the intermediate plate (8) with the crankset (3) and of another stage (8a) of the same plate (3) with the drive pinion (6) of the wheel (7) are carried out in both cases by direct engagement of the teeth of the stages (8a, 8b) of the intermediate plate (8), respectively with those of the crankset (3) and those of the pinion (6).

11. Device according to one of claims 1 to 5, characterized in that the connection of one of the stages (8b) of the intermediate plate (8) with the crankset (3) is effected by means of a chain (9), while the connection of another stage (8a) of the same intermediate plate (8) with the drive pinion (6) of the wheel (7) is effected by direct engagement of the teeth of the one (8a) with the teeth of the other (6).

12. Device according to one of claims 1 to 5, characterized in that the connection of the teeth of one of the stages (8a, 8b) of the intermediate plate (8) with those of the drive pinion (6) of the wheel (7) is effected by direct engagement of the teeth formed on their respective outer periphery.

13. Device according to one of claims 10 or 11, characterized in that the connection by direct engagement of the teeth of one of the stages (8a) of the intermediate plate (8) with those of the drive pinion (6) of the wheel (7) is effected by internal peripheral toothing of a hollow crown (12) constituting said plate (8), capable of cooperating with the external peripheral toothing of the drive pinion (6) which is housed in the manner d 'A satellite inside said ring (12) constituting the plate (8).

14. Device according to claim 13, characterized in that the stages (8a, 8b) of the intermediate plate (8) are concentric.

15. Device according to one of claims 10 to 13, characterized in that one of the stages (8b) of the intermediate plate (8) is eccentric relative to the axis of rotation thereof and is freely mounted on a part of the frame, said stage (8b) further comprising an external toothing in connection, by chain or direct drive, with the conventional crankset (3) and an internal toothing directly connected to a floor

(8c), concentric with the stage (8a) of said intermediate plate (8), which stage (8a) has an internal toothing in direct contact with the external toothing of a drive pinion (6) of the wheel (7 ).

16. Device according to one of the preceding claims, characterized in that the intermediate plate (8) is fixed freely on a part

(13) fixed to the frame of the bicycle (1).