Endless belt power transmission systems or components – Control for variable input to output speed-ratio – Including belt shiftable axially from one to another surface...
Reexamination Certificate
2001-07-25
2004-09-21
Charles, Marcus (Department: 3682)
Endless belt power transmission systems or components
Control for variable input to output speed-ratio
Including belt shiftable axially from one to another surface...
C474S080000, C474S081000
Reexamination Certificate
active
06793598
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to an optimised rear dérailleur device for a bicycle, in particular, however, not exclusively appropriate for bicycles also comprising a front dérailleur and a gearshift system, the unit being controlled by a synchronized control handle.
2. Description of Related Art
An arrangement of two dérailleurs, front and rear, controlled by a single handle is known from the European Patent Application No. 95450012.0.
This arrangement is particularly interesting for the user with regards to riding, however, the particular advantage set forth in the present application, does not represent a direct interest to the user, rather it is the limitation of the chain length.
The fact namely that the number of combinations of the disks and pinions is reduced into a subunit determined by the entirety of combinations corresponding to the product of the number of pinions by the number of disks, is due to the fact that the alignment of the chain is optimised and the length of the chain reduced.
SUMMARY OF THE INVENTION
Moreover, the market requires an improved ground clearance, in particular in the case of off-road bicycles, and it becomes clear that the rear dérailleur is particularly exposed to shocks and to getting caught, in particular when a great chain length has to be taken up.
The dérailleur according to the present invention moreover proposes a dérailleur, the ground clearance of which is considerably increased and the operation of which does not disturb the conception of the bicycle frame so that it can be mounted on the existing bicycle fleet without modification, on condition that a means for limiting the chain crossing is preferably present, so as to reduce the length of the chain, the fabrication of which necessitates pieces which can directly be industrially manufactured, the operation of which is the same for the user, the putting into service of which allows the conservation of the pinion and disk sets existing on the bicycle, and the cost of which remains within the range of prices of the dérailleurs on the market.
For that purpose, the inventive dérailleur device is characterized in that it is equipped with a front dérailleur, a chain connecting a set of pinions and at least one disk and, if the case may be, a synchronized control limiting the combinations for an adapted chain alignment and for reducing the chain length necessary in the case of several disks, characterized in that it comprises:
a rotatable base provided with a return spring forcing the so base in anti-clockwise direction
guiding/dérailleur means fixedly connected to the base, and
a movable tension plate fixedly connected to the guiding/dérailleur means.
According to a particular embodiment, the movable tension plate comprises a supporting arm, a tension arm mounted pivotable relative to the supporting arm, and a first and a second tension roller mounted freely rotatable on the ends of the tension arm, as well as a spring forcing the tension arm in anti-clockwise direction, whereby the chain passes over the first tension roller and under the second tension roller.
In particular, the tension arm is mounted onto an axis pivoting relative to the supporting arm, and the axis is essentially arranged in the centre of the tension arm or, according to a variant the axis coincides with the rotation axis of the second roller.
According to a further characteristic, the guiding/dérailleur means comprises a deformable parallelogram carrying at its end, immediately downstream of the movable tension plate and in the alignment thereof, a guiding/dérailleur roller mounted freely rotatable, whereby the chain passes over this guiding/dérailleur roller.
An improvement provides that the guiding/dérailleur roller is supported by means for adjusting the translation in the plane of the chain.
Moreover, the guiding/dérailleur roller comprises additional means for lateral guidance such as at least one flange.
In a variant which is particularly advantageous for the fabrication as well as for the user's convenience due to an improvement of the dérailleur quality, connection means interposed between the movable tension plate and the guiding/dérailleur means are provided so as to restrain the tensional stress of the chain and the return stress of the guiding means.
REFERENCES:
patent: 3111855 (1963-11-01), Juy
patent: 3364762 (1968-01-01), Maeda
patent: 3677103 (1972-07-01), Huret et al.
patent: 4610644 (1986-09-01), Nagano
patent: 4637808 (1987-01-01), Nakamura
patent: 5904629 (1999-05-01), Oka
patent: 5931753 (1999-08-01), Ichida
patent: 6135903 (2000-10-01), Savard
patent: 42 07 372 (1993-09-01), None
patent: 0 657345 (1995-06-01), None
patent: 0 727 348 (1996-08-01), None
patent: 994 334 (1951-11-01), None
patent: 2 037 543 (1970-12-01), None
patent: 2 703 020 (1994-09-01), None
patent: 2 750 668 (1998-01-01), None
patent: 2 759 968 (1998-08-01), None
patent: 64-12989 (1989-01-01), None
patent: WO 98/01333 (1998-01-01), None
Charles Marcus
Pearne & Gordon LLP
Shimano Inc.
LandOfFree
Rear derailleur device for a bicycle does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Rear derailleur device for a bicycle, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rear derailleur device for a bicycle will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3206828