I knew this derailleur as a Triplex Tximista. Tximista is the Basque word for lightning. Interestingly the public use of Basque words was suppressed under the regime of Francisco Franco. Franco died on the 20th of November 1975, and Triplex applied for this patent on... the 18th of November 1975. Spooookyy!
The design itself is an unashamed copy of a Shimano Crane - which was pretty professional, competent and advanced for 1975. The artist has entertainingly drawn the cable adjuster facing backwards which slightly destroys the illusion.