Multiple sprocket assembly for a bicycle

#The present invention relates to multiple sprocket assemblies for bicycles, and more particularly, to a multiple sprocket assembly including a smaller sprocket and a larger sprocket connected by pins.

#A multiple sprocket assembly mounted to a rear wheel is one of the main components of a drive train for mountain and racing bikes. Multiple sprocket assemblies may include as many as eleven sprockets. The sprockets are highly loaded components and thus are subject to wear. Conventional sprockets have an inner contour with a torque-transmitting profile that is mountable to a driver of a cassette hub or to an outer ring of a freewheel hub. The spacing between adjacent sprockets is critical for shifting the bicycle chain from one sprocket to the adjacent sprocket and is determined by how the torque-transmitting profile on the sprockets engage the driver or the outer ring of the freewheel hub. The sprockets are also subject to an undesirable bending load as a result of oblique chain tensile forces.

#One development trend in multiple sprocket assemblies is weight reduction. This objective may be achieved, while still satisfying the mentioned basic requirements, by support elements such as spiders disposed between the sprockets and the driver. However, the achieved weight reduction is then limited.

#In the drawings:

#FIG. 1 is a partial cross-sectional view taken along the axis of rotation of a multiple sprocket assembly according to one embodiment of the present invention;

#FIG. 2 is a partial perspective view of FIG. 1 viewed from the face of a largest sprocket without pins between the sprockets;

#FIGS. 1-9 illustrate a multiple sprocket assembly according to one embodiment of the present invention. The multiple sprocket assembly may include a plurality of individual sprockets as shown in FIGS. 1 and 2. FIGS. 3-6, 8 and 9 show a smaller sprocket and/or a larger sprocket to more easily illustrate their relationship. The smaller and larger sprockets have substantially the same design. Sprockets can be viewed as a larger or smaller sprocket depending on the next smaller or larger sprocket additionally being considered.

#FIGS. 1 and 2 show the multiple sprocket assembly 40 mounted on a driver 27 of a cassette hub in a longitudinal section along the axis of rotation. The multiple sprocket assembly 40 includes an end sprocket 16 having the largest number of teeth and having a different configuration than the other sprockets. The entire multiple sprocket assembly is supported on radial supports 9 extending radially from a rotational axis of driver 27 and sprockets 1, 2 on the driver 27. Preferably, the radial supports 9 are disposed on the end sprocket 16 and on the smallest sprocket 32. Alternatively, the radial supports 9 may be disposed on other sprockets which then the radial supports are formed as support sprockets. The sprocket assembly in the axial direction is disposed on a stop 28 of the driver 27. Pins 7 connect sprockets 1, 2. The entire sprocket assembly may also be mounted on an outer ring of a freewheel hub, which is mounted to rotate in the backward direction of rotation relative to an inner ring of the freewheel hub and has a freewheel mechanism between outer and inner rings.

#The multiple sprocket assembly also includes floating sprockets 36 which are not supported on the driver and not mounted to adjacent sprockets supported on the freewheel driver. The floating sprocket is supported by a first sprocket supported directly on the driver and a second sprocket mounted on the first sprocket.