Lucien Juy of Simplex, liked to patent everything - his own ideas and any ideas that he thought that any of his competitors might be interested in. This patent shows typical looking Simplex early 1930s derailleur designs - but with crucial differences. The differences involve the derailleur being operated by levers or cogs - both of which were mechanisms used by major competitors.

• Publisher: L’Institut national de la propriété industrielle
• Inventor: Lucien-Charles-Hippolyte Juy
• Country: France
• Date: Priority date September 1932
• Derailleur brands: Simplex
• Derailleurs: unknown