← Back to Patent Explorer
US4602307A Expired / Lapsed US ⏱️ 0.0 years remaining

Compound type magnetic head

Assignee: Mitsubishi Electric Corp
•
Filing: 1983-03-11
•
Granted: 1986-07-22
•
Expires: 2003-03-11
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A compound type magnetic head comprising a main core (11) made of a magnetic material high in saturation flux density and low in inherent resistance, such as sendust or amorphous material and two auxiliary cores (12) sandwiching the main core (11) therebetween. The auxiliary cores (12) each consist of a first member made of a material high in inherent resistance such as ferrite and a second member made of a low melting point glass portion 42 formed on the front side of the first member, namely on the side abutting against the magnetic tape.

Inventors

  • 👤 Jirou Toriu
  • 👤 Hiroshi Yamamoto
  • 👤 Shoyu Watanabe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 14:39
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/187; G11B5/255

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 240 words
In a magnetic head for recording a signal on a magnetic tape of high coerciveness for reproducing the signal recorded thereon, a compound type magnetic head comprising: a main core and two auxiliary cores sandwiching both sides of said main core therebetween, said main core being made of a magnetic material high in saturation flux density and low in inherent resistance and having a winding opening and a gap formed on the side against which said magnetic tape abuts, said auxiliary cores each consisting of a first member and a second member, said first member having a winding opening in the position corresponding to said winding opening of said main core, a gap narrower than the maximum width of the winding opening thereof at a position opposing to the gap of said main core, and glass members disposed within the gap thereof, and being made of a material high in inherent resistance, said second member being made of glass bonded to said first member so as to be located on the side against which said magnetic tape abuts and being made of a material lower in hardness than said main core, said first member has two first member halves secured by glass depositing, and glass members disposed within said gap are used for glass depositing, said second member is made of a material having a lower melting point than the glass members disposed within the gap of said first member.
Claim 2
Dependent Claim 240 words
In a magnetic head for recording a signal on a magnetic tape of high coerciveness for reproducing the signal recorded thereon, a compound type magnetic head comprising: a main core and two auxiliary cores sandwiching both sides of said main core therebetween, said main core being made of a magnetic material high in saturation flux density and low in inherent resistance and having a winding opening and a gap formed on the side against which said magnetic tape abuts, said auxiliary cores each consisting of a first member and a second member, said first member having a winding opening in the position corresponding to said winding opening of said main core, a gap narrower than the maximum width of the winding opening thereof at a position opposing to the gap of said main core, and glass members disposed within the gap thereof, and being made of a material high in inherent resistance, said second member being made of glass bonded to said first member so as to be located on the side against which said magnetic tape abuts and being made of a material lower in hardness than said main core, said first member has two first member halves secured by glass depositing, and glass members disposed within said gap are used for glass depositing, said second member is made of a material having a lower melting point than the glass members disposed within the gap of said first member.

References Cited (Backward Citations)

US4115827A Cited
US4387410A Cited
US4404608A Cited
US4475137A Cited
JPS57191821A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-07-21 1990-01-20 1990-07-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-07-21 1994-01-20 1994-07-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-07-21 1998-01-20 1998-07-22 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag