This patent is for a wacky cog-based design, that I fear never saw production. It is, however, interestingly similar to some of SunTour’s proposals for their iconic Superbe Tech derailleurs - see US Patent # 4,469,479.

• Publisher: UK Intellectual Property Office
• Inventor: Leslie Richard Bane and The Constrictor Tyre Company Ltd.
• Country: UK
• Date: UK application filed October 1945
• Derailleur brands: Constrictor, Osgear
• Derailleurs: Constrictor prototype