Single track vertical and horizontal recording read/write head design
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United States of America Patent
Stats
-
Mar 28, 1989
Grant Date -
N/A
app pub date -
Nov 12, 1987
filing date -
Nov 12, 1987
priority date (Note) -
Expired
status (Latency Note)
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Abstract
A single track read/write head design is disclosed in which a pair of solid state magnetically permeable sensors such as coupled film magneto resistive sensors are joined together with a central flux conducting probe in the general form of a T or Y connection with the probe extending downward toward a magnetic record medium to conduct flux to or from the medium for writing or reading therefrom. Alternatively, a single coupled film magneto resistive sensor may be bifurcated at its central area at the intersection with the flux coupling probe. The resultant flux coupled from the magnetic medium is divided between the two sensors, or two halves of a sensor, where it alters the magneto resistive or other magnetic property of the sensor in a differential sense, i.e., the left half or left sensor will experience an increase or decrease in resistance while the right half or right sensor experiences an opposite decrease or increase in resistivity, respectively. The design permits the magnetically permeable sensors to be located at a remote elevation or distance from the record medium to reduce wear and critical lapping problems in manufacture. Allowing the sensors to lie in a generally horizontal plane relative to the magnetic record medium permits magnetic biasing of the magneto resistive sensors in a flux path which does not enter the medium itself and thus avoids unwanted flux coupling sensor and/or bias flux to the medium which interferes with reading and writing of the data record. The differential nature of the flux energization path of the two sensors or sensor halves results in common mode noise rejection from flying height variations between the coupling probe and the medium and of other electrical disturbances common to the circuits of the sensors.
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- 15 United States
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- 2 Other
Patent Owner(s)
| Patent Owner | Address | |
|---|---|---|
| INTERNATIONAL BUSINESS MACHINES CORPORATION A CORP OF NY | ARMONK NY 10504 |
International Classification(s)
Inventor(s)
| Inventor Name | Address | # of filed Patents | Total Citations |
|---|---|---|---|
| Thompson, David A | San Jose, CA | 70 | 3891 |
| Vinal, Albert W | Cary, NC | 42 | 979 |
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| Fee | Large entity fee | small entity fee | micro entity fee | due date |
|---|
| Fee | Large entity fee | small entity fee | micro entity fee |
|---|---|---|---|
| Surcharge after expiration - Late payment is unavoidable | $700.00 | $350.00 | $175.00 |
| Surcharge after expiration - Late payment is unintentional | $1,640.00 | $820.00 | $410.00 |
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