Transducer head with laminated pole tips for wideband transducer system

Claim 2

A magnetic transducer head according to claim 1 with the laminations having been machined from hot-pressed sintered magnetic material exhibiting an initial permeability of about 15, 000, and a porosity of less than 1 percent.

Claim 3

A composite magnetic transducer head comprising a ferrite magnetic core having magnetic pole tips defining a coupling gap for coupling of the core with a record medium, characterized in that at least one of the pole tips comprises laminations machined from an ingot of hot-pressed sintered iron-silicon-aluminum alloy, said laminations having a mechanical hardness of about Vickers 650 (measured at a 300 gram load) and a thickness of about five to six mils, said laminations having substantially smooth side surfaces, and a bonding layer between the successive laminations and mechanically bonding the laminations as a unitary structure, said laminations having a porosity of less than about 0.1 percent and an initial permeability of about 15,000.

Claim 4

A magnetic head comprising a magnetic core having magnetic pole tips defining a coupling gap for coupling of the core with a record medium, characterized in that the pole tips comprise laminations machined from a hot-pressed sintered iron-silicon-aluminum alloy, said laminations having a mechanical hardness of about Vickers 650 (measured at a 300-gram load) and a thickness of less than eight mils, said laminations having lapped side surfaces which are substantially flat and smooth, and a bonding layer between successive laminations mechanically bonding the laminations as a unitary structure and having a thickness of less than 300 microinches, said laminations having an initial permeability of about 15,000.

Claim 5

A magnetic head according to claim 5 with said laminations of said alloy having been annealed in a vacuum furnace by raising the temperature of the heating chamber thereof from about room temperature to a temperature of about 800* C. in from about 1/2 hour to about 1 hour and then allowing the heating chamber to cool back to room temperature at an unforced rate.

Claim 6

A magnetic head in accordance with claim 6 wherein the laminations of said hot-pressed sinterEd iron-silicon-aluminum alloy have been given a rapid dip acid treatment subsequent to the annealing thereof.

Claim 7

A composite multitrack magnetic transducer head assembly comprising a support bracket having a series of ferrite magnetic cores therein, the cores having respective pairs of edge faces all lying substantially in a common plane, a pole tip assembly comprising a plate secured to said bracket and having secured thereto a series of pairs of pole tips with undersurfaces lying in closely spaced confronting relation to the respective edge faces to define respective head units for cooperation with respective channels of a magnetizable layer of a magnetic record medium, said pole tips each comprising a series of laminations machined from an ingot of iron-silicon-aluminum alloy having a hardness of at least about Rockwell C- 40, and means providing an electrically insulating layer between said undersurfaces of said pole tips and the edge faces of said ferrite magnetic cores.

Claim 8

A multitrack magnetic transducer head assembly according to claim 8 with said laminations having been machined from hot-pressed sintered magnetic material and having been annealed and then etched with a viscous acid solution subsequent to annealing, the laminations of each pole tip assembly having successive bonding layers therebetween mechanically bonding the laminations as a unitary structure and providing a substantially uniform spacing between the successive laminations of less than 300 microinches.