US3717846A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for the detection of faults in a magnetic recording medium
Assignee: Fujitsu Ltd
•
Filing: 1971-12-22
•
Granted: 1973-02-20
•
Expires: 1991-12-22
Abstract
Abstract A system for the detection of faults in a magnetic recording medium such as a magnetic tape used in an information processing unit. The system is adapted to directly record information, provide an indication of erroneously recorded information, and erase that portion of the recording medium upon which information is erroneously recorded. The erase procedure is accompanied by a simultaneous reading by the read head of the portion of the magnetic recording medium being erased to determined the presence or absence of faults thereon which is indicated by the generation of corresponding noise signals. The system issues a tape reject signal when the noise signals generated by the faults comprise at least a predetermined number.
Inventors
- 👤 K Kanda
- 👤 T Nagahori
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:25
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B20/18; G11B20/1816
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
144 words
In a system for the detection of faults in a magnetic recording medium for an external auxiliary memory device of an information processing unit, in which a write head and a read head are adjacently disposed, data information being recorded by the write head onto the magnetic recording medium and being sequentially read by the read head, with means to detect errors in information recorded onto the magnetic recording medium by the write head, the improvement comprising: means to erase the portion of the magnetic recording medium upon which data information is erroneously recorded, with the read head being connected to read said portion during the erasing operation. detection means connected to the read head to detect faults in the magnetic recording medium from noise signals generated when the read head is connected to read the portion of the magnetic recording medium being erased.
Claim 2
Dependent Claim
144 words
In a system for the detection of faults in a magnetic recording medium for an external auxiliary memory device of an information processing unit, in which a write head and a read head are adjacently disposed, data information being recorded by the write head onto the magnetic recording medium and being sequentially read by the read head, with means to detect errors in information recorded onto the magnetic recording medium by the write head, the improvement comprising: means to erase the portion of the magnetic recording medium upon which data information is erroneously recorded, with the read head being connected to read said portion during the erasing operation. detection means connected to the read head to detect faults in the magnetic recording medium from noise signals generated when the read head is connected to read the portion of the magnetic recording medium being erased.
Claim 3
Dependent Claim
144 words
In a system for the detection of faults in a magnetic recording medium for an external auxiliary memory device of an information processing unit, in which a write head and a read head are adjacently disposed, data information being recorded by the write head onto the magnetic recording medium and being sequentially read by the read head, with means to detect errors in information recorded onto the magnetic recording medium by the write head, the improvement comprising: means to erase the portion of the magnetic recording medium upon which data information is erroneously recorded, with the read head being connected to read said portion during the erasing operation. detection means connected to the read head to detect faults in the magnetic recording medium from noise signals generated when the read head is connected to read the portion of the magnetic recording medium being erased.
Claim 4
Dependent Claim
144 words
In a system for the detection of faults in a magnetic recording medium for an external auxiliary memory device of an information processing unit, in which a write head and a read head are adjacently disposed, data information being recorded by the write head onto the magnetic recording medium and being sequentially read by the read head, with means to detect errors in information recorded onto the magnetic recording medium by the write head, the improvement comprising: means to erase the portion of the magnetic recording medium upon which data information is erroneously recorded, with the read head being connected to read said portion during the erasing operation. detection means connected to the read head to detect faults in the magnetic recording medium from noise signals generated when the read head is connected to read the portion of the magnetic recording medium being erased.
Claim 5
Dependent Claim
32 words
In the system recited in claim 1, further comprising: means connected to the erase means to predetermine the length of the magnetic recording medium to be erased when an error is detected.
Claim 6
Dependent Claim
62 words
In the system recited in claim 1, further comprising: means to temporarily store an indication of the length of a block of information recorded onto the magnetic recording medium by the write head, and responsive upon detection of an error in the recorded information to control the erase means to erase the magnetic recording medium a length corresponding to said stored indication.
Claim 7
Dependent Claim
59 words
In the system recited in claim 1 further comprising: means connected to the detection means to determine the number of noise signals generated when the read head is connected to read the portion of the magnetic recording medium being erased, and responsive to the generation of a predetermined number of said noise signals to issue a tape reject signal.
Claim 8
Dependent Claim
37 words
In the system recited in claim 1 further comprising: means connected to the detection means and responsive to the generation of a predetermined number of noise signals during a given time to generate a tape reject signal.
Claim 9
Dependent Claim
44 words
In the system recited in claim 1 further comprising: counter means responsive to count the noise signals occurring during a predetermined time period and responsive to cause a tape reject signal to be issued when a predetermined count is reached during said predetermined time.
Claim 10
Dependent Claim
18 words
In the system recited in claim 6 wherein the counter means is reset after said predetermined time expires.
References Cited (Backward Citations)
US2975407A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-20 | 1976-08-21 | 1977-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-20 | 1980-08-21 | 1981-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-20 | 1984-08-21 | 1985-02-20 | $7700.00 | Window Closed / Lapsed |