Articulated aquatic flipper

Claim 1

AN ARTICULATED AQUATIC FLIPPER ADAPTED FOR USE AS AN AID IN PROPELLING A PERSON IN A BODY OF WATER COMPRISING AN ELONGATED, LONGITUDINALLY RIGID SUPPORT PLATE PROVIDING A SUBSTANTIALLY PLANE LOWER SURFACE ADAPTED TO CONTACT THE HAND OF A WEARER AND A TRANSVERSELY ARCUATELY CURVED SURFACE PARTIALLY TO EMBRACE THE WRIST AND FOREARM OF THE WEARER; A PLURALITY OF JOINTED RIB MEMBERS, EACH HAVING AT LEAST TWO ELONGATED SECTIONS PIVOTALLY INTERCONNECTED FOR RELATIVE MOVEMENT ABOUT A RESPECTIVE TRANSVERSE AXIS, EACH OF THE MEMBERS PROVIDING A FORWARDLY PROJECTING DISTAL END AND A REARWARD PROXIMAL END; REINFORCING MEANS IN THE FORM OF AN UPSTANDING ELONGATED CHANNEL ELEMENT HAVING A CROSS-SECTIONAL CONFIGURATION OF AN INVERTED U AND BEING INTEGRALLY CARRIED BY EACH OF THE MEMBERS TO AFFORD LONGITUDINAL RIGIDITY THERETO; MEANS CONNECTING EACH OF SAID RIB MEMBERS TO THE SUPPORT PLATE FOR PIVOTAL MOVEMENT ABOUT RESPECTIVE TRANSVERSE AXES TO AND FROM AN EXTENDED SWIMMING POSITION AND A RETRACTED RETURN-STROKE POSITION; A PLURALITY OF STOP PINS CARRIED BY THE PLATE TO LIMIT THE RANGE OF MOVEMENT OF SAID RIB MEMBERS TO SAID EXTENDED SWIMMING POSITION; A STOP PIN CARRIED BY EACH OF THE RIB MEMBERS ADJACENT TO SAID PIVOTAL INTERCONNECTION OF THE SECTIONS TO LIMIT THE RANGE OF PIVOTAL MOVEMENT TO AN EXTENDED POSITION; A WEB OF FLEXIBLE, SUBSTANTIALLY IMPERVIOUS, STRETCH-RESISTANT, WATERPROOF MATERIAL EXTENDED BETWEEN SAID RIB MEMBERS TO PROVIDE A REACTION SURFACE WHEN IN AN EXTENDED SWIMMING POSITION; AND MEANS SECURED TO THE SUPPORT PLATE AND ADAPTED FOR RELEASABLY ATTACHING THE PLATE TO THE ARM OF A WEARER.