US4609956A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic drum cassette with magnetic drum having voice information recorded thereon
Assignee: FDK Corp
•
Filing: 1983-08-29
•
Granted: 1986-09-02
•
Expires: 2003-08-29
Abstract
Abstract A magnetic drum and parts ancillary thereto are enclosed in a housing consisting of an upper casing and a lower casing to form a cassette-type magnetic drum unit for voice information system. The magnetic drum cassette is releasable from the system which includes a magnetic head for reproducing the voice information stored in the magnetic drum.
Inventors
- 👤 Michihiro Torii
- 👤 Takao Moritomo
- 👤 Kaoru Endo
- 👤 Norifumi Ito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 03:56
CPC Classifications
G; G11; G11B; G11B25/00; G11B25/02; G11B17/00; G11B17/02; G11B17/04; G11B19/00; G11B19/20; G11B23/00; G11B23/50; G11B5/00; G11B5/41; G11B5/48; G11B5/54; G11B5/55; G11B5/5591; G11B5/74; G11B5/76
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
169 words
A magnetic drum/head system for reproducing a recorded information, comprising a magnetic drum cassette having therein a magnetic drum driven by a capstan, a magnetic head contacting an information track on the magnetic drum for generating selected recorded information, wherein said magnetic drum cassette comprises: a lower casing having a bearing at its central portion; an upper casing fitted to said lower casing to form a housing for enclosing therein said magnetic drum; an oil coating device mounted on resilient means fixed to said housing to slidably contact with the circumference of said magnetic drum; an opening in said housing for permitting said magnetic head through said opening; and, a cover, slidably mounted on means formed on said housing, for opening and closing said opening in the housing, thereby protecting said magnetic drum when said cassette is released from said system; wherein said cover has a cleaner plate for cleaning said magnetic head when said cover is repeatedly slid manually in and out of contact with the magnetic head.
Claim 2
Dependent Claim
169 words
A magnetic drum/head system for reproducing a recorded information, comprising a magnetic drum cassette having therein a magnetic drum driven by a capstan, a magnetic head contacting an information track on the magnetic drum for generating selected recorded information, wherein said magnetic drum cassette comprises: a lower casing having a bearing at its central portion; an upper casing fitted to said lower casing to form a housing for enclosing therein said magnetic drum; an oil coating device mounted on resilient means fixed to said housing to slidably contact with the circumference of said magnetic drum; an opening in said housing for permitting said magnetic head through said opening; and, a cover, slidably mounted on means formed on said housing, for opening and closing said opening in the housing, thereby protecting said magnetic drum when said cassette is released from said system; wherein said cover has a cleaner plate for cleaning said magnetic head when said cover is repeatedly slid manually in and out of contact with the magnetic head.
Claim 3
Dependent Claim
32 words
The system according to claim 1, wherein said magnetic drum cassette has a friction ring on said magnetic drum, said friction ring being engaged by said capstan for driving said magnetic drum.
Claim 4
Dependent Claim
21 words
The system according to claim 2, wherein said housing has a through hole at said lower casing for receiving said capstan.
Claim 5
Dependent Claim
109 words
The system according to claim 1, wherein said system includes a carriage including means mounting said magnetic head in an abutting relationship to said magnetic drum, and a carriage driver for selectively moving said carriage relative to said magnetic drum, thereby shifting the position of said magnetic head to a selected information track of said magnetic drum, wherein said carriage driver comprises: a driving screw extended through said carriage; a needle resiliently engaged with said driving screw; and, a guide means, connected to said carriage, for limiting the movement of said needle and forcibly shifting the position of said carriage via said needle when said driving screw is rotated.
Claim 6
Dependent Claim
33 words
The system according to claim 4, wherein said magnetic head is supported by a leaf spring horizontally and pivotally mounted on said carriage, thereby resiliently pressing said magnetic head against said magnetic drum.
References Cited (Backward Citations)
US3482060A
Cited
US3618120A
Cited
US4225893A
Cited
US4333116A
Cited
US4376961A
Cited
US4422112A
Cited
US4445157A
Cited
US4439792A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-09-01 | 1990-03-03 | 1990-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-01 | 1994-03-03 | 1994-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-09-01 | 1998-03-03 | 1998-09-02 | $7700.00 | Window Closed / Lapsed |