Electroacoustic transducer with improved electromagnetic drive

Claim 1

IN COMBINATION IN AN ELECTROMAGNETIC TRANSDUCER, TWO PAIRS OF RIGID UNITARY STRUCTURES EACH COMPRISING A FIRST TIGHTLY-WOUND COIL ASSEMBLY OF THIN MAGNETICALLY CONDUCTING STRIP MATERIAL, A SECOND TIGHTLY-WOUND COIL ASSEMBLY OF THIN MAGNETICALLY CONDUCTING STRIP MATERIAL HAVING THE SAME GENERAL SHAPE AS SAID FIRST COIL ASSEMBLY AND HAVING AN INTERNAL SURFACE IN SUBSTANTIALLY UNIFORMLY SPACED FACING RELATION TO THE OUTSIDE SURFACE OF SAID FIRST COIL ASSEMBLY TO DEFINE A CLEARANCE SPACE, SPACING MEANS SUBSTANTIALLY FILLING SAID CLEARANCE SPACED, AND BONDING MEANS BETWEEN SAID INSIDE AND OUTSIDE SURFACES OF SAID COIL ASSEMBLIES AND SAID SPACING MEANS, OPPOSITE END SURFACES OF SAID COIL ASSEMBLIES OF EACH RIGID UNITARY STRUCTURE BEING MACHINED TO LIE IN PARALLEL PLANES, A RIGID CIRCULAR PLATE HAVING OPPOSITELY FACING PARALLEL SURFACE PORTIONS BONDED TO END SURFACES OF COIL ASSEMBLIES OF ONE PAIR OF SAID RIGID UNITARY STRUCTURES, A PAIR OF BASE MEMBERS HAVING PLANAR SURFACES BONDED TO END SURFACES OF COIL ASSEMBLIES OF THE OTHER PAIR OF SAID RIGID-UNITARY STRUCTURES, SPRING MEMBERS SUPPORTING SAID BASE MEMBERS FROM OPPOSITE SIDES OF SAID RIGID CIRCULAR PLATE WITH END SURFACES OF THE COIL ASSEMBLIES OF SAID ONE PAIR OF RIGID UNITARY STRUCTURES IN SPACED