US Patent 10106224 Front derailleur device for a bicycle chain shift

A front derailleur device for a bicycle chain shift includes a frame fixing part for attachment to a bicycle frame, a hinge arrangement which is pivotable relative to the frame fixing part, and a chain cage which is pivotable relative to the frame fixing part via the pivotable hinge arrangement for guiding and pivoting of the bicycle chain. The hinge arrangement includes at least two hinged struts which can be mounted rotatably relative to the frame fixing part and relative to the chain cage about pivot axes. The pivot axes run substantially parallel to each other and, in a mounted state of the derailleur device on a bicycle, may be oriented substantially vertically.