Patent ID: 8475306

Claim:
A chain transmission comprising: a driving shaft provided with one or more sprockets; a driven shaft provided with complementary sprockets, which is coupled to the driving shaft via a chain; and at least one chain-moving element mounted on a gear shifting shaft and provided between the driving shaft and the driven shaft, near one or the other of the sprockets of the driving shaft or driven shaft, by means of which a desired transmission ratio can be set via axial movement of the chain, wherein the at least one chain-moving element comprises a set of axially movable chain retaining side plates mounted to a sliding block which is movable over the gear shifting shaft, wherein the chain transmission comprises at least one guide shaft provided between the driving shaft and the driven shaft, on which guide shaft there is mounted an element having a conical shape, wherein the side plates comprise a ridge that moves over the element having a conical shape, and wherein the movement of the ridge over the element having a conical shape moves at least one end of the side plates to a position close to a contact point between the chain and the respective sprocket with every transmission ratio that is set, and wherein said ridge forms part of a fork within which said element is positioned, thus preventing excessive rotation of the side plates connected to the ridge over the sliding block.