Electromagnetic apparatus for moving a rod structure within a tubular housing

Claim 1

ELECTROMAGNETIC APPARATUS FOR MOVING A ROD STRUCTURE WITHIN AN ENCLOSURE BY MAGNETIC FORCE APPLIED FROM THE OUTSIDE, COMPRISING A TUBULAR HOUSING AND A ROD STRUCTURE LONGITUDINALLY DISPLACEABLE THEREIN, A NUMBER OF ELECTROMAGNETS ALIGNED ALONG SAID HOUSING AT THE OUTSIDE THEREOF AND HAVING UNIFORMLY SPACED MAGNET POLES OF ALTERNATELY DIFFERENT POLARITY, SAID ROD STRUCTURE HAVING MAGNETIZABLE TEETH FORMING ARMATURES FOR SAID RESPECTIVE MAGNETS, THE NUMBER OF SAID TEETH ALONG A GIVEN LENGTH OF SAID ROD STRUCTURE BEING DIFFERENT FROM THE NUMBER OF POLES ALONG THE SAME LENGTH OTHER THAN BY AN INTEGRAL RATIO IN ACCORDANCE WITH A GIVEN VERNIER RATIO FOR DISPLACEMENT OF SAID STRUCTURE BY SEQUENTIAL ENERGIZATION OF SAID MAGNETS, SAID RESPECTIVE MAGNET POLES HAVING AN AXIAL WIDTH EQUAL TO THE SUM OF THE CORRESPONDING WIDTH OF ONE OF SAID RESPECTIVE TEETH PLUS TWICE THE WALL THICKNESS OF SAID HOUSING AT THE THINNEST LOCATION BETWEEN EACH TWO SUCCESSIVE ONES OF SAID MAGNET POLES.