Abstract: A quarter-turn pin valve actuator has a housing and a rotatable core configured to rotate about a central axis inside the housing. The rotatable core has a two bearings mounted to roll in a circular path about the central axis. The actuator comprises a two-position ramped roller plate that is displaced axially when the bearings are rolled a quarter turn. The actuator includes a push plate and a spring disposed between the push plate and the ramped roller plate. The push plate has a central socket for receiving a pin of a pin valve to which the actuator is connected. When the rotatable core is rotated, the bearings exert a force via the ramped roller plate on the push plate which in turn displaces a pin of a pin valve to which the actuator is connected.