Classifications

• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/127—Structure or manufacture of heads, e.g. inductive
  • G11B5/187—Structure or manufacture of the surface of the head in physical contact with, or immediately adjacent to the recording medium; Pole pieces; Gap features
  • G11B5/1871—Shaping or contouring of the transducing or guiding surface
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/127—Structure or manufacture of heads, e.g. inductive
  • G11B5/29—Structure or manufacture of unitary devices formed of plural heads for more than one track
  • G11B5/295—Manufacture

Definitions

• This invention relates generally to magnetic transducers and more particularly to a magnetic transducer assembly with multiple magnetic cores and a non-magnetic integral slider.
• the above-referenced applications are assigned to ehe same assignee as this application and disclose and claim subject matter related to the present application.
• Magnetic disc recording systems commonly utilize a plurality of magnetic transducers that are positioned near the surface of a rotating disc. These magnetic transducers are separated from the surface of the rotating disc by a relatively thin fluid bearing, to form what is commonly called a "flying" head. While some magnetic disc recording systems position one magnetic core adjacent to each magnetic track contained on the surface of the disc, other systems employ fewer magnetic cores and means for alternatively positioning these cores adjacent to the desired tracks.
• the magnetic transducers used in either of the above systems include a plurality of magnetic cores that are carried in some manner upon a slider riding upon a thin fluid bearing proximate to the surface of the rotating disc.
• a exemplary julti-channel magnetic head is disclosed in Solyst U.S. Patent No. 3,579,214.
• the slider disclosed therein is formed from a ferromagnetic block which is relatively expensive and magnetically couples together the multiple magnetic cores, thereby creating interference between adjacent cores.
• a second exemplary magnetic transducer is commonly termed a Winchester slider as referenced in Wiseley U.S. Patent No. 4,141,050, column 2, lines 50-56.
• the Winchester slider employe three fluid bearing surfaces each having a magnetic core embedded therein.
• a third example of a multi-channel magnetic transducer assembly is disclosed in Neace U.S. Pat. No. 3,792,492 which describes an assembly of a plurality of magnetic cores mounted on a non-magnetic spacer which is bonded into a slotted air bearing member. This transducer assembly requires that the magnetic core and spacer combination be fitted into the air bearing member, increasing the manufacturing complexity and cost, and additionally increasing the total mass of the magnetic core, spacer and air bearing member combination.
• the magnetic transducer assembly of the present invention provides relatively narrow magnetic cores that are fixed to a non-magnetic slider in a generally low mass combination, thus overcoming the limitations descrid above.
• the magnetic transducer assembly comprises a plurality of magnetic cores bonded to the trailing edge of a non-magnetic ceramic slider to form a flying head for magnetic disc.
• the surface of the slider nearest the disc includes a plurality of fluid bearing surfaces for supporting the magnetic transducer assembly on a fluid bearing near a rotating disc, and also includes leading edge surfaces. Trailing edge surfaces are provided by the magnetic cores, and a magnetizing coil is wound around each magnetic core.
• a notched surface of a ferrite block is joined to a first surface of a ferrite plate.
• the obverse surface of the ferrite plate is next joined to a block of non-magnetic ceramic material such as barium titanate.
• a channel is machined into a first surface of the ceramic block parallel to the ferrite block and plate to form a suitable mounting surface.
• a plurality of notches are formed into the assembly of the ferrite block and plate as well as the ceramic block, to define the fluid bearing surfaces.
• Portions of the ferrite block and plate are then removed to define individual magnetic cores that are Isolated by the non-magnetic ceramic block.
• Individual magnetic transducers including four magnetic cores are machined from the assembly of the ferrite block, ferrite plate and ceramic block.
• a hydrodynamic leading edge is then formed on the leading edge of the fluid bearing surfaces of the magnetic transducers, and a trailing edge is formed on the magnetic cores of the transducers. It is thus an object of this invention to provide an improved magnetic transducer assembly with multiple magnetic cores.
• Figure 1 is a perspective view of the magnetic transducer assembly depicting the fluid bearing surfaces and the magnetic cores.
• Figure 2 is a perspective view of the magnetic transducer assembly depicting the fluid bearing surfaces and the magnetic cores.
• FIGS 3-7 illustrate the magnetic transducer assembly manufacturing steps.
• the bonding technique utilizes a glass 28, as is well known to those skilled in the art, to achieve a gap 29 between the ferrite block 13 and the ferrite plate 27 in the range of twenty-five micro-inches to seventy-five micro-inches.
• An exemplary manufacturer of magnetic transducer assemblies utilizing such techniques is Magnetic Arts, 1310 Industrial Avenue, Escondido, California 92025.
• Each bar assembly 51 and 52 has a forward surface 53 and 54, which originally comprised the surface 45 of the ceramic base 40, and a trailing surface 55 and 56 which originally comprised the surface 20 of the ferrite block 13. Additionally, two new fluid bearing surfaces 60 and 61 are formed. The surface 60 is opposite from and parallel to the surface 44 of bar assembly 51; the surface 61 is similarly opposite from and parallel to the surface 43 of the bar assembly 52.
• the fluid bearing surfaces of the magnetic cores 7a-d are then ground to define a trailing edge angle into trailing edges lOa-d which may, for example, be on the order of eight degrees.
• the trailing edge angle may begin approximately within five-thousandths an inch from the gap originally formed at 29 (Fig. 4) and generally designated 29a-d in Fig. 2.
• the magnetic transducer assembly 1 is further ground to define a leading edge angle on the order of one-half degree into leading edges 9a-f which extend approximately forty-thousands of an inch from the leading edge surface 131. It will be remembered that the surface 131 was originally part of the forward surface 54 of the bar assembly 52.
• a length of wire 94 is wound through each magnetic core 2a-d in a manner that is well known in the art to form magnetizing coils lla-d.

Landscapes

• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Adjustment Of The Magnetic Head Position Track Following On Tapes (AREA)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

Country Status (3)

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Citations (3)

Family Cites Families (9)

• 1980
  • 1980-05-30 JP JP50145380A patent/JPS56500630A/ja active Pending
  • 1980-05-30 WO PCT/US1980/000648 patent/WO1980002769A1/en not_active Ceased
  • 1980-12-15 EP EP19800901254 patent/EP0029458A4/en not_active Withdrawn

Patent Citations (3)

Non-Patent Citations (1)

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