{"schema_version":"1.0","canonical_url":"https://patentable.app/patents/US-9721603","patent":{"patent_number":"US-9721603","title":"Head-medium contact detection using an oscillating electromagnetic force","assignee":null,"inventors":[],"filing_date":"2016-08-16T00:00:00.000Z","publication_date":"2017-08-01T00:00:00.000Z","cpc_codes":["G11B","G11B","G11B","G11B"],"num_claims":17,"abstract":"An apparatus comprises circuitry configured to apply an AC signal having a frequency to one of a slider of a recording head and a magnetic recording medium. The applied AC signal causes an oscillation in an electrostatic force and clearance between the slider and the medium at the frequency of the AC signal. A thermal sensor is configured to generate a sensor signal at the AC signal frequency in response to sensing changes in temperature resulting from the oscillating clearance. A detector is coupled to the circuitry and the thermal sensor. The detector is configured to detect one or both of head-medium spacing changes and head-medium contact using a phase of a first harmonic or an amplitude of a second harmonic of the thermal sensor signal."},"analysis":{"summary":null,"layman_explanation":null,"technical_analysis":null,"business_analysis":null,"faqs":null,"topics":[],"tech_cluster":null},"seo":{"title":"Head-medium contact detection using an oscillating electromagnetic force","description":"An apparatus comprises circuitry configured to apply an AC signal having a frequency to one of a slider of a recording head and a magnetic recording medium. The applied AC signal causes an oscillation","keywords":[]},"attribution":{"source":"Patentable","source_url":"https://patentable.app","canonical_url":"https://patentable.app/patents/US-9721603","license":"CC-BY-4.0-like","license_terms":"AI-generated analysis on this page (summary, layman_explanation, technical_analysis, business_analysis, faqs) may be reused with attribution and a visible link back to the canonical URL above. Patent abstracts, claims, and bibliographic data are USPTO public domain.","required_link":"https://patentable.app/patents/US-9721603","citation_suggestion":"Patentable. \"Head-medium contact detection using an oscillating electromagnetic force\" (US-9721603). https://patentable.app/patents/US-9721603","copyright_holder":"Nomic Interactive Technology LLC"},"links":{"html":"https://patentable.app/patents/US-9721603","json":"https://patentable.app/api/llm-context/US-9721603","site":"https://patentable.app","llms_txt":"https://patentable.app/llms.txt"},"generated_at":"2026-06-06T06:25:14.427Z"}