US3775571A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic heads
Assignee: Fujitsu Services Ltd
•
Filing: 1972-04-28
•
Granted: 1973-11-27
•
Expires: 1992-04-28
Abstract
Abstract To offset damage to the pole face surfaces of ferrite head blocks of magnetic transducing heads which are easily susceptible to wear and impact damage. The head block is reinforced by providing a reinforcing member surrounding the pole face surface such that one surface of the reinforcing member provides a surface co-extensive with the pole face surface, the combined area of the co-extensive surfaces being greater than the cross sectional area of the head block providing the pole face surface.
Inventors
- 👤 D Case
- 👤 K Stammers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:30
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/187; G11B5/255; G11B5/1871; G11B5/48; G11B5/58; G11B5/60; G11B5/6005; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49021; Y10T29/49027; Y10T29/4903; Y10T29/49032; Y10T29/49036; Y10T29/49041
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
132 words
A method of reinforcing the pole face of a magnetic transducing head having ferrite pole pieces separated by a nonmagneTic gap arranged to form an operative pole face including the steps of preforming a reinforcing collar from non-magnetic material, the collar being formed with a pair of opposite faces and an aperture extending therethrough from one to the other of the faces, the dimensions of the aperture being arranged to permit the collar to be fitted about the operative pole face of the head; locating the head within the aperture of the collar to bring the operative pole face of the head into alignment with one of the faces of the collar; and bonding the head and the collar together so that the collar provides a reinforcement about said operative pole face.
Claim 2
Independent Claim
132 words
A method of reinforcing the pole face of a magnetic transducing head having ferrite pole pieces separated by a nonmagneTic gap arranged to form an operative pole face including the steps of preforming a reinforcing collar from non-magnetic material, the collar being formed with a pair of opposite faces and an aperture extending therethrough from one to the other of the faces, the dimensions of the aperture being arranged to permit the collar to be fitted about the operative pole face of the head; locating the head within the aperture of the collar to bring the operative pole face of the head into alignment with one of the faces of the collar; and bonding the head and the collar together so that the collar provides a reinforcement about said operative pole face.
Claim 3
Dependent Claim
14 words
A method as claimed in claim 1, in which the non-magnetic material is metallic.
Claim 4
Dependent Claim
14 words
A method as claimed in claim 2, in which the non-magnetic material is copper.
Claim 5
Dependent Claim
14 words
A method as claimed in claim 1, in which the non-magnetic material is non-metallic.
Claim 6
Dependent Claim
15 words
A method as claimed in claim 4, in which the non-magnetic material is a glass.
Claim 7
Dependent Claim
116 words
A magnetic transducing head including a head assembly having ferrite pole pieces separated by a non-magnetic gap arranged to form an operative pole face; and a preformed non-magnetic reinforcing collar having a wear resistance and mechanical strength comparable with that of the ferrite, the collar being formed with a pair of opposite faces and an aperture extending therethrough from one to the other of the faces, the dimensions of the aperture being arranged to permit the collar to be fitted about the operative pole face of the head; and in which the collar is bonded about the head assembly with one face of the collar being aligned with the operative face to form an extension thereto.
Claim 8
Dependent Claim
116 words
A magnetic transducing head including a head assembly having ferrite pole pieces separated by a non-magnetic gap arranged to form an operative pole face; and a preformed non-magnetic reinforcing collar having a wear resistance and mechanical strength comparable with that of the ferrite, the collar being formed with a pair of opposite faces and an aperture extending therethrough from one to the other of the faces, the dimensions of the aperture being arranged to permit the collar to be fitted about the operative pole face of the head; and in which the collar is bonded about the head assembly with one face of the collar being aligned with the operative face to form an extension thereto.
References Cited (Backward Citations)
US3177495A
Cited
US3335412A
Cited
US3308450A
Cited
US3670112A
Cited
US3584378A
Cited
US3665436A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-26 | 1977-05-28 | 1977-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-26 | 1981-05-28 | 1981-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-26 | 1985-05-28 | 1985-11-27 | $7700.00 | Window Closed / Lapsed |