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US4118747A Expired / Lapsed US ⏱️ 0.0 years remaining

Composite magnetic head

Assignee: Olympus Corp
•
Filing: 1977-03-04
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Granted: 1978-10-03
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Expires: 1997-03-04
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Abstract

Abstract A composite magnetic head including a record/playback gap and an erase gap comprises a straight central core, a pair of arcuate lateral cores having their ends disposed in opposing relationship with the opposite ends of the central core disposed therebetween, each of the lateral cores being formed with a bobbin carrying portion at its one end which extends in a direction perpendicular to the length of the central core, a bobbin having a central flange and a pair of flanges at the opposite ends, the central flange being formed with an opening for receiving the central core and the bobbin being formed with a slot extending through the entire length of the bobbin including the flanges at the opposite ends for receiving the lateral cores, the slot extending in a direction perpendicular to the opening which receives the central core, and a pair of coils disposed between the central flange and the respective end flanges, the central core and the lateral cores forming a record/playback gap and an erase head at their one end when the cores and the bobbin are assembled together by inserting the remote end of the central core into the opening and inserting one end of the lateral cores into the slot.

Inventors

  • 👤 Naohiro Hanaoka
  • 👤 Misao Shimoda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 16:14
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/265; G11B5/2651

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 200 words
A composite magnetic head including a record/playback gap and an erase gap, comprising: a straight, central core; a pair of lateral cores disposed in mutually opposite relationship with a front end and a rear end of the central core so as to hold the ends of the central core therebetween, each of the lateral cores having a rear portion which extends in a direction perpendicular to the length of the central core to provide a bobbin carrying portion; a bobbin having a central flange and a pair of end flanges, the central flange being formed with an opening for receiving the central core and the bobbin being formed with a slot extending through the length thereof including both end flanges in a direction perpendicular to the opening; a pair of coils respectively disposed between the central flange and each of the end flanges; the central core being disposed in the opening and the bobbin carrying portions of the lateral cores being disposed in the slot in such a manner that a record/playback gap and an erase gap are defined between the opposite sides of the front end of the central core and each front end of the both lateral cores.
Claim 2
Dependent Claim 200 words
A composite magnetic head including a record/playback gap and an erase gap, comprising: a straight, central core; a pair of lateral cores disposed in mutually opposite relationship with a front end and a rear end of the central core so as to hold the ends of the central core therebetween, each of the lateral cores having a rear portion which extends in a direction perpendicular to the length of the central core to provide a bobbin carrying portion; a bobbin having a central flange and a pair of end flanges, the central flange being formed with an opening for receiving the central core and the bobbin being formed with a slot extending through the length thereof including both end flanges in a direction perpendicular to the opening; a pair of coils respectively disposed between the central flange and each of the end flanges; the central core being disposed in the opening and the bobbin carrying portions of the lateral cores being disposed in the slot in such a manner that a record/playback gap and an erase gap are defined between the opposite sides of the front end of the central core and each front end of the both lateral cores.
Claim 3
Dependent Claim 32 words
A composite magnetic head according to claim 1 in which the end flanges of the bobbin each have conductive terminals fixedly mounted thereon for connection with the lead wires of the coils.
Claim 4
Dependent Claim 63 words
A composite magnetic head according to claim 1 in which the bottom surface of the slot is finished to a high precision to define the position of the respective cores so that the front ends of the central core and the both lateral cores are maintained in proper abutting relationship to define the record/playback gap and the erase gap of a given size.
Claim 5
Dependent Claim 313 words
A composite magnet head assembly incorporating a record/playback gap and an erase gap comprising: a coil supporting bobbin composed of a body having a straight, longitudinal opening extending along the length of the body and communicating with both ends thereof; a flange surrounding the body intermediate the ends of said body and first and second end flanges surrounding the body at respective ends thereof; said central flange having an opening extending therethrough and communicating with said longitudinal opening; first and second lateral cores each comprised of a first and second arm, the ends of one arm of each of said lateral cores being curved generally toward the remaining straight arm; the straight arms being inserted into respective opposite ends of the opening in said bobbin; the cross-sectional configuration of said straight arms conforming to the cross-section of the longitudinal opening in said bobbin; a central core being substantially straight and having a cross-section conforming to the cross-section of the opening in said intermediate flange; one end of said central core being inserted into the opening in said central flange and being positioned between the ends of the straight arms of said lateral cores, the opening in said intermediate flange and the longitudinal opening in the body of said bobbin being adapted to position the opposite ends of said lateral cores in said central core so as to provide a first gap between said central core and the free curved end of one of said lateral cores and between the opposite side of said central core and the free end of the curved arm of the remaining lateral core; a suitable insulating material of precision thickness being provided on the free end of the straight arm of each lateral core to provide precision spacing for the aforesaid gaps between the curved ends of said lateral cores and the adjacent surfaces of said central core.
Claim 6
Dependent Claim 313 words
A composite magnet head assembly incorporating a record/playback gap and an erase gap comprising: a coil supporting bobbin composed of a body having a straight, longitudinal opening extending along the length of the body and communicating with both ends thereof; a flange surrounding the body intermediate the ends of said body and first and second end flanges surrounding the body at respective ends thereof; said central flange having an opening extending therethrough and communicating with said longitudinal opening; first and second lateral cores each comprised of a first and second arm, the ends of one arm of each of said lateral cores being curved generally toward the remaining straight arm; the straight arms being inserted into respective opposite ends of the opening in said bobbin; the cross-sectional configuration of said straight arms conforming to the cross-section of the longitudinal opening in said bobbin; a central core being substantially straight and having a cross-section conforming to the cross-section of the opening in said intermediate flange; one end of said central core being inserted into the opening in said central flange and being positioned between the ends of the straight arms of said lateral cores, the opening in said intermediate flange and the longitudinal opening in the body of said bobbin being adapted to position the opposite ends of said lateral cores in said central core so as to provide a first gap between said central core and the free curved end of one of said lateral cores and between the opposite side of said central core and the free end of the curved arm of the remaining lateral core; a suitable insulating material of precision thickness being provided on the free end of the straight arm of each lateral core to provide precision spacing for the aforesaid gaps between the curved ends of said lateral cores and the adjacent surfaces of said central core.

References Cited (Backward Citations)

US2418542A Cited
US3969770A Cited
US4012783A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-10-02 1982-04-03 1982-10-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-10-02 1986-04-03 1986-10-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-10-02 1990-04-03 1990-10-03 $7700.00 Window Closed / Lapsed

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