公开(公告)号：DE1909724A1

公开(公告)日：1969-09-04

申请号：DE1909724

申请日：1969-02-26

Applicant: IBM

Inventor： MARIE HOOGENDOORN HELEN ,  EDWIN LIBERMAN HERBERT ,  NARKEN BERNT ,  SUNNERS BRIAN

IPC: G11B5/105 ,  G11B5/127 ,  G11B5/133 ,  G11B5/23 ,  G11B5/24

Abstract: 1,251,699. Making magnetic heads. INTERNATIONAL BUSINESS MACHINES CORP. 25 Feb., 1969 [29 Feb., 1968], No. 9888/69. Headings B3A and B3V. [Also in Divisions C1 and G5] In the mounting of a ferrite head 11 in a ceramic housing 14, the head 11 is positioned by clamping jaws 15 in a slot 13 in the housing and the slot filled with a first mass of molten glass, as by melting glass disc 16, to bonding the glass to head 11 and housing 14, creating a gap 18 between the head 11 and the glass 16 as by machining with diamond saw wheels 19, heating a second mass 20 of glass with infra-red radiation 17 to fill the gap 18 without disturbing the bond between the first glass 16 and the housing 14 and to bond the first glass 16 with the head 11. After cooling, the protruding glass 16, 20 and ferrite head 11 are ground and polished so as to be aligned with the ceramic housing 14. Multihead assemblies may be similarly fabricated. Preferably the first mass of glass 16 is also heated by infra-red radiation; the second mass of glass 20 being more infrared absorbent than the first mass. Both may be low temperature glasses with lead oxide in the range 50-80% by weight, Cupric oxide up to 7% by weight is added to improve infra-red absorption, the first glass preferably having 0À05 to 1% and the second 3%. The sealing glasses have coefficients of thermal expansion less than or equal to the coefficients of the head 11 and housing 14, which may be similar or with the ceramic having the greater coefficient. Two glasses suitable for the first mass of glass 16 and a third for both glasses with varying cupric oxide additions are given, in percentages by weight:-