The present invention relates to pivotal connections of a bicycle derailleur between a parallelogram and either a base member connected to a bicycle frame or a chain cage for guiding a bicycle chain.
DE 101 57 213 A1 discloses a bicycle rear derailleur with a pin-mounted parallelogram. Links of the parallelogram are connected to a base member and to a chain cage by inserting pivot pins into aligned bores of one of the links and one of the base member and the chain cage. To prevent the pivot pins from axially displacing, a securing ring is snapped into a groove on the pivot pin. In one embodiment, the securing ring is axially supported on the parallelogram link and on the base member or the chain cage. In another embodiment, the securing ring is arranged in a recess in the parallelogram link that is laterally supported in a recess in the base member or the chain cage.
One drawback of the above pivot connection between the parallelogram link and the base member or the chain cage is that it does not have any defined bearing surfaces, resulting in the pivot pin rotating in the base member or the chain cage as well as in the parallelogram link. Further, there is no covering over either end of the pivot pin, such that dirt is not prevented from entering between the pin and the mounting bore.
The present invention provides a bicycle derailleur having a pivotal connection including a defined bearing surface and a maximum distance between the bearings. In addition, the bearing is protected from dirt and the pivot pin is attached so as to protect it from loss. The bicycle derailleur may be a front or rear derailleur.
The bicycle derailleur generally includes a base member, a chain cage and a parallelogram pivotally connected at one end to the base member and at other end to the chain cage by pivot pins. Generally, the pivotal connection is between an inner pivot part and an outer pivot part. The inner pivot part may be the parallelogram or one of the base member and the chain cage and the outer pivot part may be the parallelogram or one of the base member and the chain cage. In the present invention, the pivotal connection includes first and second bushings that are precisely defined and disposed as far outwards as possible. For this purpose, one of the two pivot parts is guided in the area of the bushing by the other pivot part. For this invention, it is irrelevant whether the base member or the parallelogram is disposed on the outside on the pivot and surrounds the other part on two sides. The pivot pin further includes a anti-rotation contour to prevent it from rotating in the inner pivot part. The anti-rotation contour may include toothing, a knurl or the like.
In one embodiment of the present invention, the pivot connection may also include a securing element to prevent axial displacement of the pivot pin. The securing element may also define the distance between the inner and outer pivot parts and prevent against loss of the pivot pin. The securing element engages a holding contour, in this embodiment a groove or bore in the pivot pin. The securing element may be a securing ring, snap ring, splint, securing disc or the like. In order to fix the position of the pivot parts, on the one side, the pin head contacts the outer pivot part and, on the other side, the securing element engages the holding contour, preferably a circumferential groove on the pivot pin, and is supported on the inner pivot part. The securing element is disposed between the mounting points, in the vicinity of the inner pivot part. The axial displacement of the pivot pin is prevented by the pin head and the securing element. The distance between the pin head and the securing element defines the position of the pivot parts. After the pivot parts and pivot pin have been joined, the securing element is mounted in a recess in the inner pivot part. In order to mount the securing element, the inner and outer pivot parts must assume a defined position or angle relative to one another. The recess is accessible during the installation process, but later is almost completely covered after installation by the inner pivot part.
In another embodiment, the securing element may be omitted. The axial securing of the pivot pin is accomplished by deforming the inner pivot part into the holding contour of the pivot pin or by a clip element disposed on or integrated with the inner pivot part and engaging the holding contour. The clip element may be elastic. After installation, the pivot pin is axially secured by exerting a force against a deformation section of the inner pivot part to deform that section of the inner pivot part into the holding contour of the pivot pin. This additional installation step may be omitted if the clip element is arranged on an end of a through bore on the inner pivot part that, after mounting, engages in the holding contour in the form of a circumferential groove on the pivot pin. Instead of one or more clip elements, the pivot pin may also be prevented from axially displacing by a local narrowing of the through bore on the end of the inner pivot part or by a corresponding enlargement of the pivot pin diameter. In the interaction between the local narrowing or enlargement with the contour of the corresponding adjacent component, it becomes possible to secure the pivot pin from loss without any additional components.
In another embodiment, the pivotal connection further includes first and second bushings. An end of the pivot pin opposite the pin head is mounted in a blind hole of the outer pivot part. With this configuration, the pivotal connection, in particular the bushings, are shielded from outside environmental influences, on one side by the pin head and on the other side by the blind hole. The first and second bushings are separated by a certain distance, resulting in a stable, play-free and maintenance free pivot mounting. Further, the bushings provide a clean appearance of the derailleur and no further components are needed to seal it off from dirt or for optionally covering the mounting and securing elements.
These and other features and advantages of the invention will be more fully understood from the following description of certain embodiments of the invention, taken together with the accompanying drawings.
In the drawings:
a is a perspective view of the rear derailleur showing a partial cross section of a pivotal connection between the parallelogram mechanism and the base member in accordance with one embodiment of the present invention;
b is a blow-up of detail A of
a is a perspective view of the rear derailleur showing a partial cross section of a pivotal connection between the parallelogram mechanism and the chain cage in accordance with one embodiment of the present invention; and
b is a blow-up of detail B of
Looking to
Looking to
Looking to
While this invention has been described by reference to several embodiments, it will be understood that numerous changes could be made within the spirit and scope of the inventive concepts described. Accordingly, it is intended that the invention not be limited to the disclosed embodiments, but that it include the full scope permitted by the language of the following claims.
Number | Date | Country | Kind |
---|---|---|---|
10 2005 034 330 | Jul 2005 | DE | national |
Number | Name | Date | Kind |
---|---|---|---|
2566872 | Bernhardt | Sep 1951 | A |
2716033 | Dodge | Aug 1955 | A |
2838331 | Coleman | Jun 1958 | A |
4675940 | Brockhaus | Jun 1987 | A |
5720082 | Rossmo | Feb 1998 | A |
5884365 | Kluting | Mar 1999 | A |
6203459 | Calendrille, Jr. | Mar 2001 | B1 |
6290621 | Ichida | Sep 2001 | B1 |
6682252 | Battey et al. | Jan 2004 | B2 |
6837815 | Meggiolan | Jan 2005 | B2 |
20040014541 | Dal Pra | Jan 2004 | A1 |
20060035737 | Nankou | Feb 2006 | A1 |
Number | Date | Country |
---|---|---|
76 03 439 | Sep 1976 | DE |
35 18 798 | Nov 1985 | DE |
40 10 466 | Oct 1991 | DE |
44 11 084 | Oct 1994 | DE |
44 11 085 | Oct 1994 | DE |
197 28 641 | Jan 1998 | DE |
101 57 213 | Jun 2002 | DE |
1 010 613 | Jun 2000 | EP |
1 099 620 | May 2001 | EP |
1 357 023 | Oct 2003 | EP |
1 447 317 | Aug 2004 | EP |
988 439 | Apr 1965 | GB |
21 46 698 | Apr 1985 | GB |
WO 9427008 | Nov 1994 | WO |
Number | Date | Country | |
---|---|---|---|
20070021247 A1 | Jan 2007 | US |