Fluid motor actuator having two pistons reversely movable in a common cylinder, the pistons each carrying at least three extensions on their proximal sides, one of which being provided with a rack camming with one common spur gear fastened on a transverse shaft projecting from the cylinder, the extensions...http://www.google.es/patents/US4203351?utm_source=gb-gplus-sharePatente US4203351 - Fluid motor actuator for rotating a shaft back and forth
Fluid motor actuator for rotating a shaft back and forth
