Writer core incorporating thermal sensor having a temperature coefficient of resistance

Patent metadata

Field	Value
Publication number	US-9159349-B2
Application number	US-201314012480-A
Country	US
Kind code	B2
Filing date	Aug 28, 2013
Priority date	Aug 28, 2013
Publication date	Oct 13, 2015
Grant date	Oct 13, 2015

Abstract

A writer core of a transducer is configured to interact with a magnetic recording medium and comprises an upper core and a lower core. At least one of the upper and lower cores comprises a return pole having a return shield. The apparatus also comprises a writer pole between the upper and lower cores, and a writer gap defined between the writer pole and the return shield. The apparatus further comprises a sensor element within one of the upper and lower cores that includes the writer gap. The sensor element has a temperature coefficient of resistance and is configured to sense for a change in temperature indicative of one or both of a change in spacing and contact between the transducer and the magnetic recording medium.

First claim

What is claimed is:

1. An apparatus, comprising:
a writer core of a transducer, the writer core configured to interact with a magnetic recording medium and comprising an upper core and a lower core;
at least one of the upper and lower cores comprising a return pole having a return shield;
a writer pole between the upper and lower cores;
a writer gap defined between the writer pole and the return shield; and
a sensor element within one of the upper and lower cores that includes the return shield and the writer gap, the sensor element situated at or near the return shield such that a change in temperature experienced by the sensor element is the same or substantially the same as that experienced by the return shield, the sensor element having a temperature coefficient of resistance and configured to sense for a change in temperature indicative of one or both of a change in spacing and contact between the transducer and the magnetic recording medium.

2. The apparatus of claim 1 , wherein the sensor element is spaced apart from the return shield.

3. The apparatus of claim 1 , wherein the sensor element is integral to the return shield.

4. The apparatus of claim 1 , wherein the sensor element is at or near a distal end of the return shield proximate the writer gap.

5. The apparatus of claim 1 , wherein:
a portion of the return shield is at or near an airbearing surface of the transducer; and
the sensor element is spaced apart from the return shield portion and away from the airbearing surface.

6. The apparatus of claim 1 , wherein:
the apparatus comprises a leading edge and a trailing edge; and
the upper core is situated more closely to the trailing edge than the lower core.

7. The apparatus of claim 1 , further comprising a reader of the transducer, wherein:
the reader is situated more closely to the lower core than the upper core; and
the upper core comprises the return shield.

8. The apparatus of claim 1 , wherein:
the sensor element is spaced apart from the return shield; and
the spacing between the sensor element and the return shield allows for a change in temperature at the return shield resulting from one or both of the spacing change and contact to be sensed by the sensor element.

9. The apparatus of claim 1 , wherein:
the sensor element is spaced apart from the return shield; and
the spacing between the sensor element and the return shield is such that a change in temperature experienced by the thermal sensor is the same or substantially the same as that experienced by the return shield.

10. The apparatus of claim 1 , wherein the apparatus comprises a writer heater proximate the writer core and configured to thermally activate at least the writer pole, the return shield, and the sensor element.

11. The apparatus of claim 1 , wherein the writer core further comprises a spacer between the thermal sensor and the return shield, the spacer comprising a material having a temperature coefficient of resistance.

12. The apparatus of claim 1 , wherein the sensor element is separated from the writer pole by less than about 300 nm.

13. The apparatus of claim 1 , wherein the sensor element is configured to sense one or both of a change in modulation of transducer-media spacing during flight and a change in thermal conductivities.

14. An apparatus, comprising:
a writer core of a transducer, the writer core configured to interact with a magnetic recording medium and comprising an upper core and a lower core;
at least one of the upper and lower cores comprising a return pole having a return shield;
a writer pole between the upper and lower cores;
a writer gap defined between the writer pole and the return shield; and
a sensor element within one of the upper and lower cores that includes the writer gap and the return shield, the sensor element situated at or near the return shield such that a change in temperature experienced by the sensor element is the same or substantially the same as that experienced by the return shield, the sensor element having a temperature coefficient of resistance and configured to:
sense for a change in temperature indicative of one or both of a change in spacing and contact between the transducer and the magnetic recording medium; and
enhance a gradient of a magnetic field generated by the write core.

15. The apparatus of claim 14 , wherein the temperature sensor is integral to the return shield.

16. The apparatus of claim 14 , wherein the sensor element is configured to:
sense, in a first mode, for the change in temperature indicative of one or both of the change in spacing and contact between the transducer and the magnetic recording medium;
enhance, in a second mode, the magnetic field generated by the write core; and
the first and second modes are separated in time.

17. The apparatus of claim 14 , comprising circuitry coupled to the writer core and configured to actively synchronize magnetic responses of the write pole and the return shield during write operations.

Assignees

• Seagate Technology Llc

Inventors

• Peng Peng
• Macken Declan
• Johnson Michael Thomas
• Guo Zheying

Classifications

• G11B5/6076 Primary

  Detecting head-disk contact · CPC title

• G11B5/607

  using thermal means · CPC title

• G11B5/3143

  including additional layers for improving the electromagnetic transducing properties of the basic structure, e.g. for flux coupling, guiding or shielding (G11B5/3116, G11B5/312 take precedence) · CPC title

• G11B5/3133

  including layers not usually being a part of the electromagnetic transducer structure and providing additional features, e.g. for improving heat radiation, reduction of power dissipation, adaptations for measurement or indication of gap depth or other properties of the structure (G11B5/3106 takes precedence) · CPC title

• G11B5/1278

  specially adapted for magnetisations perpendicular to the surface of the record carrier · CPC title