Method of making a multi-channel magnetic head assembly

Claim 1

The method of making a multi-channel magnetic head assembly comprising the steps of: forming a pole tip assembly having a pair of magnetic elements joined together at a non-magnetic gap and including plural spaced apart grooves extending into the assembly in a direction generally normal to the non-magnetic gap to form extensions from a common base of a generally comb-like structure; bonding the extensions of the pole tip assembly within slots in a slotted air bearing member; removing the common base of the pole tip assembly; forming a core base structure having a base and spaced pairs of upstanding legs extending from the base; and joining the upstanding legs of the core base structure to the extensions of the pole tip assembly.

Claim 2

The method of making a multi-channel magnetic head assembly comprising the steps of: forming a pole tip assembly having a pair of magnetic elements joined together at a non-magnetic gap and including plural spaced apart grooves extending into the assembly in a direction generally normal to the non-magnetic gap to form extensions from a common base of a generally comb-like structure; bonding the extensions of the pole tip assembly within slots in a slotted air bearing member; removing the common base of the pole tip assembly; forming a core base structure having a base and spaced pairs of upstanding legs extending from the base; and joining the upstanding legs of the core base structure to the extensions of the pole tip assembly.

Claim 5

The method of making a multi-channel magnetic head assembly comprising the steps of: preparing a pole tip assembly having comb-like elements extending from a common base from two elements of magnetic material including lapping flat opposed surfaces, grooving the lapped surfaces of one element along a longitudinal line, joining the grooved surface of the one element to the lapped surface of the other element with an intermediate spacer, and cutting grooves through the joined structure in a direction normal to the lapped surfaces to form the comb-like elements; preparing a slotted air bearing member; inserting the comb-like elements of the pole tip assembly through the slotted air bearing member to a selected depth; bonding the pole tip assembly to the air bearing member; preparing a unitary core structure having a flat side, including cutting into the flat side to define transverse inter-channel grooves and a longitudinal intermediate groove, the inter-channel and intermediate grooves defining legs on the core structure; adding coil windings to the legs of the unitary core structure; joining legs of the unitary core structure to the comb-like elements of the pole tip assembly; and removing the common base of the pole tip assembly.

Claim 6

The method of making a multi-channel magnetic head assembly comprising the steps of: preparing a pole tip assembly having comb-like elements extending from a common base from two elements of magnetic material including lapping flat opposed surfaces, grooving the lapped surfaces of one element along a longitudinal line, joining the grooved surface of the one element to the lapped surface of the other element with an intermediate spacer, and cutting grooves through the joined structure in a direction normal to the lapped surfaces to form the comb-like elements; preparing a slotted air bearing member; inserting the comb-like elements of the pole tip assembly through the slotted air bearing member to a selected depth; bonding the pole tip assembly to the air bearing member; preparing a unitary core structure having a flat side, including cutting into the flat side to define transverse inter-channel grooves and a longitudinal intermediate groove, the inter-channel and intermediate grooves defining legs on the core structure; adding coil windings to the legs of the unitary core structure; joining legs of the unitary core structure to the comb-like elements of the pole tip assembly; and removing the common base of the pole tip assembly.

Claim 7

The method of making a multi-channel magnetic head assembly for magnetic disk recording comprising: lapping flat a face of a block of magnetic ferrite material; cutting a longitudinal groove through the lapped face in the ferrite block; cutting transverse, longitudinally spaced grooves through the lapped face in the ferrite block to define pairs of core legs; placing pre-wound coils about at least one of each pair of core legs; forming a ceramic air bearing with multi-channel slots and an air bearing surface; lapping a ''''Sendust'''' block having a single gap longitudinally disposed to form a flat base; cutting legs in the ''''Sendust'''' block from the flat base; mounting the legs of the ''''Sendust'''' block in the slots of the ceramic air bearing, joining the ''''Sendust'''' block to the ceramic air bearing; machining the air bearing surface and included portions of the legs of the ''''Sendust'''' block while cutting off the base of the ''''Sendust'''' block to form gap elements in thE multi-channel slots; and mounting gap elements on the ends of the core legs.

Claim 8

The method of making a multi-channel magnetic head assembly for magnetic disk recording comprising: lapping flat a face of a block of magnetic ferrite material; cutting a longitudinal groove through the lapped face in the ferrite block; cutting transverse, longitudinally spaced grooves through the lapped face in the ferrite block to define pairs of core legs; placing pre-wound coils about at least one of each pair of core legs; forming a ceramic air bearing with multi-channel slots and an air bearing surface; lapping a ''''Sendust'''' block having a single gap longitudinally disposed to form a flat base; cutting legs in the ''''Sendust'''' block from the flat base; mounting the legs of the ''''Sendust'''' block in the slots of the ceramic air bearing, joining the ''''Sendust'''' block to the ceramic air bearing; machining the air bearing surface and included portions of the legs of the ''''Sendust'''' block while cutting off the base of the ''''Sendust'''' block to form gap elements in thE multi-channel slots; and mounting gap elements on the ends of the core legs.

Claim 9

The method of making a multi-channel air bearing magnetic head assembly comprising the steps of: preparing a pair of rectangular bars of magnetic material, each having a lapped reference surface on one side thereof and a pole tip surface adjacent thereto, with a transverse groove along the reference surface of one of the bars; substantially filling the transverse groove of said one of the bars with a high temperature adhesive; placing the reference surfaces of the bars in facing relation with an interposed non-magnetic spacer; pressing the pair of bars together at an elevated temperature in a reducing atmosphere to unify the structure; cutting interchannel grooves to a selected depth in the unified structure from the pole tip surface and past the transverse groove therein, the interchannel grooves being regularly spaced in the transverse direction to define separate legs; lapping the ends of the legs to define a selected gap depth; inserting the legs of the unified structure in receiving slots in an air bearing member with the free ends being on an air bearing side of the member; bonding the unified structure to the air bearing member with an epoxy resin; lapping the side of the assembly thus formed opposite the air bearing side to remove a base of the unified structure and to provide a flat surface; cleaning epoxy from the air bearing side; lapping a rectangular magnetic ferrite bar to provide a smooth reference surface on a first side thereof; fixing the ferrite bar to a non-magnetic ferrite back; cutting a transverse groove in the ferrite bar from the reference surface to provide a U-shaped cross-section; cutting interchannel grooves in the ferrite bar to define individual core leg pairs; and adding coils to the core leg pairs and attaching the flat ends of the core leg pairs to the legs of the unified structure.

Claim 10

The method of making a multi-channel air bearing magnetic head assembly comprising the steps of: preparing a pair of rectangular bars of magnetic material, each having a lapped reference surface on one side thereof and a pole tip surface adjacent thereto, with a transverse groove along the reference surface of one of the bars; substantially filling the transverse groove of said one of the bars with a high temperature adhesive; placing the reference surfaces of the bars in facing relation with an interposed non-magnetic spacer; pressing the pair of bars together at an elevated temperature in a reducing atmosphere to unify the structure; cutting interchannel grooves to a selected depth in the unified structure from the pole tip surface and past the transverse groove therein, the interchannel grooves being regularly spaced in the transverse direction to define separate legs; lapping the ends of the legs to define a selected gap depth; inserting the legs of the unified structure in receiving slots in an air bearing member with the free ends being on an air bearing side of the member; bonding the unified structure to the air bearing member with an epoxy resin; lapping the side of the assembly thus formed opposite the air bearing side to remove a base of the unified structure and to provide a flat surface; cleaning epoxy from the air bearing side; lapping a rectangular magnetic ferrite bar to provide a smooth reference surface on a first side thereof; fixing the ferrite bar to a non-magnetic ferrite back; cutting a transverse groove in the ferrite bar from the reference surface to provide a U-shaped cross-section; cutting interchannel grooves in the ferrite bar to define individual core leg pairs; and adding coils to the core leg pairs and attaching the flat ends of the core leg pairs to the legs of the unified structure.