Multi-track magnetic heads and their method of manufacture

Claim 1

A METHOD OF FORMING A MULTI-TRACK MAGNETIC HEAD WITH A PLURALITY OF FINISHED MAGNETIC HEADS HAVING GAP AND BODY PORTIONS, EACH OF SAID HEADS BEING SPACED FROM ONE ANOTHER WITHIN RELATIVELY SMALL STACKING TOLERANCES AND BONDED TO A HOLDER COMPOSED OF A SINGLE RIGID NONMAGNETIC FERRITE UNIT HAVING AN OPEN END, A CLOSED END DEFINED BY INNER AND OUTER SURFACES FORMING A CENTER PORTION AND ENGAGED BY SUBSTANTIALLY PARALLEL SIDE PORTIONS EACH DEFINED BY PLANAR INNER AND OUTER SURFACES WHICH FORM A SUBSTANTIALLY RECTANGULAR U-SHAPED CROSSSECTION, COMPRISING THE STEPS OF: GRINDING THE OUTER SURFACE OF THE CENTER PORTION OF SAID RIGID HOLDER SUBSTANTIALLY FLAT; MILLING FROM SAID OUTER SURFACE OF THE CENTER PORTION TO CUT AT RIGHT ANGLES TO SAID SIDE PORTIONS A FIRST PLURALITY OF PARALLEL, EQUALLY SPACED, EQUAL WIDTH, EQUAL LENGTH, HEAD RECEIVING SLOTS IN THE CENTER PORTION OF SAID HOLDER, EACH SLOT OF SAID FIRST PLURALITY OF SLOTS BEING RESPECTIVELY MILLED THROUGH TO THE INNER SURFACE OF THE CENTER PORTION TO ORTHOGONALLY INTERSECT AND EXPOSE SAID INNER SIDE PORTION SURFACES, EACH SAID SLOT HAVING A MINIMUM LENGTH EQUAL TO THE DISTANCE BETWEEN SAID INNER SIDE PORTION SURFACES AND A WIDTH EQUAL TO THE GAP WIDTH AND BODY THICKNESS OF A FINISHED FERRITE MAGNETIC HEAD; MILLING A SECOND PLURALITY OF EQUALLY SPACED, PARALLEL SCREENING PLATE RECEIVING SLOTS INTO THE MATERIAL OF THE CENTER PORTION DEFINING SAID FIRST PLURALITY OF SLOTS, EACH OF SAID PLATE RECEIVING SLOTS BEING FORMED PARALLEL TO SAID FIRST PLURALITY OF SLOTS AND BETWEEN ADJACENT ONES THEREOF; INSERTING AN INDIVIDUAL FINISHED FERRITE MAGNETIC HEAD HAVING A GAP CONTAINING PLANAR FRONT SURRFACE DEFINED BY ASSEMBLED MAGNETIC CIRCUIT BODY PORTIONS, BETWEEN SAID INNER SURFACES OF SAID SIDE PORTIONS FROM THE OPEN END OF SAID U-SHAPED CROSS-SECTION INTO EACH SLOT OF SAID FIRST PLURALITY OF SLOTS UNTIL EACH SAID FRONT SURFACE OF EACH INDIVIDUAL MAGNETIC HEAD IS SUBSTANTIALLY COPLANAR WITH SAID OUTER SURFACE OF SAID CENTER PORTION OF THE HOLDER TO RENDER SAID RELATIVELY SMALL STACKING TOLERANCE AND RESULT IN EACH HEAD BODY PORTION BEING DISPOSED BETWEEN SAID INNER SURFACE; INSERTING A SCREEN PLATE INTO EACH OF SAID PLATE RECEIVING SLOTS; CEMENTING SAID HOLDER, THE ASSEMBLED GAP CONTAINING HEADS, AND THE ASSEMBLED SCREEN PLATES TOGETHER; AND ROUNDING OFF SAID COPLANAR FRONT AND OUTER SURFACES OF THE CEMENTED ASSEMBLY.

Claim 2

A METHOD OF FORMING A MULTI-TRACK MAGNETIC HEAD WITH A PLURALITY OF FINISHED MAGNETIC HEADS HAVING GAP AND BODY PORTIONS, EACH OF SAID HEADS BEING SPACED FROM ONE ANOTHER WITHIN RELATIVELY SMALL STACKING TOLERANCES AND BONDED TO A HOLDER COMPOSED OF A SINGLE RIGID NONMAGNETIC FERRITE UNIT HAVING AN OPEN END, A CLOSED END DEFINED BY INNER AND OUTER SURFACES FORMING A CENTER PORTION AND ENGAGED BY SUBSTANTIALLY PARALLEL SIDE PORTIONS EACH DEFINED BY PLANAR INNER AND OUTER SURFACES WHICH FORM A SUBSTANTIALLY RECTANGULAR U-SHAPED CROSSSECTION, COMPRISING THE STEPS OF: GRINDING THE OUTER SURFACE OF THE CENTER PORTION OF SAID RIGID HOLDER SUBSTANTIALLY FLAT; MILLING FROM SAID OUTER SURFACE OF THE CENTER PORTION TO CUT AT RIGHT ANGLES TO SAID SIDE PORTIONS A FIRST PLURALITY OF PARALLEL, EQUALLY SPACED, EQUAL WIDTH, EQUAL LENGTH, HEAD RECEIVING SLOTS IN THE CENTER PORTION OF SAID HOLDER, EACH SLOT OF SAID FIRST PLURALITY OF SLOTS BEING RESPECTIVELY MILLED THROUGH TO THE INNER SURFACE OF THE CENTER PORTION TO ORTHOGONALLY INTERSECT AND EXPOSE SAID INNER SIDE PORTION SURFACES, EACH SAID SLOT HAVING A MINIMUM LENGTH EQUAL TO THE DISTANCE BETWEEN SAID INNER SIDE PORTION SURFACES AND A WIDTH EQUAL TO THE GAP WIDTH AND BODY THICKNESS OF A FINISHED FERRITE MAGNETIC HEAD; MILLING A SECOND PLURALITY OF EQUALLY SPACED, PARALLEL SCREENING PLATE RECEIVING SLOTS INTO THE MATERIAL OF THE CENTER PORTION DEFINING SAID FIRST PLURALITY OF SLOTS, EACH OF SAID PLATE RECEIVING SLOTS BEING FORMED PARALLEL TO SAID FIRST PLURALITY OF SLOTS AND BETWEEN ADJACENT ONES THEREOF; INSERTING AN INDIVIDUAL FINISHED FERRITE MAGNETIC HEAD HAVING A GAP CONTAINING PLANAR FRONT SURRFACE DEFINED BY ASSEMBLED MAGNETIC CIRCUIT BODY PORTIONS, BETWEEN SAID INNER SURFACES OF SAID SIDE PORTIONS FROM THE OPEN END OF SAID U-SHAPED CROSS-SECTION INTO EACH SLOT OF SAID FIRST PLURALITY OF SLOTS UNTIL EACH SAID FRONT SURFACE OF EACH INDIVIDUAL MAGNETIC HEAD IS SUBSTANTIALLY COPLANAR WITH SAID OUTER SURFACE OF SAID CENTER PORTION OF THE HOLDER TO RENDER SAID RELATIVELY SMALL STACKING TOLERANCE AND RESULT IN EACH HEAD BODY PORTION BEING DISPOSED BETWEEN SAID INNER SURFACE; INSERTING A SCREEN PLATE INTO EACH OF SAID PLATE RECEIVING SLOTS; CEMENTING SAID HOLDER, THE ASSEMBLED GAP CONTAINING HEADS, AND THE ASSEMBLED SCREEN PLATES TOGETHER; AND ROUNDING OFF SAID COPLANAR FRONT AND OUTER SURFACES OF THE CEMENTED ASSEMBLY.