| 摘要 |
A system (13) for determining the position of a piston (3) along its path of travel (9) in a cylinder (2) of a fluid-dynamic actuator (1), wherein the surface of the rod (5) of the piston (3) is provided with first grooves (14) machined on respective sections (15) of the rod (5), so that projections of the first grooves (14) onto a first plane parallel to the rod axis (6) define segments (14a) arranged obliquely with respect to the axis (6), and second grooves (17) extending parallel to the axis (6) for respective lengths such that a respective number of second grooves (17) run across each section (15), optical sensors (19, 21) detect the presence of second grooves (17) through a second plane (20) transversal to the axis (6) and a displacement (32) of segments (14a) along a line (31) coplanar with the second plane (20) due to a movement of the piston (3), and a processing unit (22) counts the detected second grooves (17) and determines the position of the piston (3) as a function of the count of second grooves (17) and the displacement (32) of segments (14a).
|
