# US 5,704,715 A · Altitude insensitive air bearing slider > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,704,715 A - Document ID: US5704715A - Status: Granted - Kind: A - Application number: 08/700,759 - Filed: 1996-12-09 - Granted: 1998-01-06 - Earliest claimed: 1996-12-09 - Assignees: Read-Rite Corporation - Inventors: Ciuter Chang; Yiao-Tee Hsia; Pablo G. Levi; Christopher A. Lee - Web page: https://patentgrep.com/patent/US5704715A ## CPC - G11B 5/6005: {Specially adapted for spacing from a rotating disc using a fluid cushion} - F16C 32/0662: {Details of hydrostatic bearings independent of fluid supply or direction of load} - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) - F16C: SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS ## Abstract The air bearing surface of an air bearing slider is configured with a taper formed at the slider leading end and a rail that is formed with a base and two legs. One leg extends from the base partially toward the trailing end. The other leg extends from the base to the trailing end and is integrally formed of a rectangularly shaped section and one or more polygon-shaped sections. Inner and outer recesses are defined and separated by the rail, such that the slider is effectively insensitive to changes in ambient pressure, particularly from variations in altitude, so that a substantially constant flying height can be maintained. ## Claims ### Claim 1 An air bearing slider having an air bearing surface, a leading end and a trailing end and first and second parallel sides between said leading and trailing ends comprising: a taper formed at the leading end; a rail extending from said taper towards the trailing end, said rail being formed in the general shape of the numeral "7", with a base and first and second legs; said first leg being shorter than said second leg, said first leg extending partially from said base toward the trailing end; said second leg extending from said base to the trailing end, said second leg configured with at least one polygon-shaped section; and inner and outer recesses defined and separated by said rail; whereby said slider is effectively insensitive to changes in ambient pressure and to variations in altitude, so that a substantially constant flying height of said slider can be maintained. ### Claim 2 (depends on 1) An air bearing slider as is in claim 1, wherein said second leg includes a trailing end that coincides with the slider trailing end; said slider including a magnetic transducer disposed at the trailing end of said second leg for interaction with a magnetic medium. ### Claim 3 (depends on 1) An air bearing slider as is in claim 1, wherein said polygon-shaped section is formed of a first angled side that defines an angle "a" relative to the first side of said slider and a second angled side that defines a different angle "b" relative to said slider first side. ### Claim 4 (depends on 3) An air bearing slider as is in claim 3, wherein said angle "a" ranges between 5 and 75 degrees. ### Claim 5 (depends on 3) An air bearing slider as is in claim 3, wherein said angle "b" ranges between 5 and 75 degrees. ### Claim 6 (depends on 1) An air bearing slider as is in claim 1, wherein said polygon-shaped section is formed with an angled side that defines an angle "c" relative to the first side of said slider and an angled side that defines an angle "d" relative to the first side of said slider wherein said angles "c" and "d" are in the range of -45 to +45 degrees. ### Claim 7 (depends on 1) An air bearing slider as in claim 1, wherein said second leg includes a trailing end that is not coplanar with said trailing end of said slider; and wherein said slider includes a magnetic transducer disposed at the trailing end of said second leg. ### Claim 8 (depends on 1) An air bearing slider as is in claim 1, including rail defined steps extending from the slider leading end to the slider trailing end. ### Claim 9 (depends on 8) An air bearing slider as in claim 8, wherein said rail defined steps are of the same depth as said recesses. ### Claim 10 (depends on 1) An air bearing slider as in claim 1, wherein each of said recesses is formed to a depth of about 1 to 5 microns. ### Claim 11 (depends on 10) An air bearing slider as in claim 10, wherein said recesses are formed to a similar depth by etching. ### Claim 12 (depends on 11) An air bearing slider as in claim 11, wherein said etching comprises reactive ion etching, ion milling, or laser etching. ### Claim 13 (depends on 1) An air bearing slider as in claim 1, wherein each of said recesses are etched to different depths. ### Claim 14 (depends on 1) An air bearing slider as in claim 1, wherein said inner recess is defined by said rail and one side of said slider, and said outer recess is defined by said rail and the side opposite to said one side of said slider. ### Claim 15 (depends on 1) An air bearing slider as in claim 1, wherein said taper is formed as a single shallow etched step. ### Claim 16 (depends on 15) An air bearing slider as in claim 15, wherein said taper is etched to a depth between 5 to 40 microinches. ### Claim 17 (depends on 1) An air bearing slider as in claim 1, wherein said taper is formed with a notch. ### Claim 18 (depends on 1) An air bearing slider as in claim 1, wherein said taper is formed with at least two steps. ### Claim 19 (depends on 18) An air bearing slider as in claim 18, wherein said taper includes a hybrid taper comprised of a beveled chamfer and at least one step. ### Claim 20 (depends on 18) An air bearing slider as in claim 18, wherein said taper includes a notch. ### Claim 21 (depends on 1) An air bearing slider as in claim 1, including a channel formed across said taper and said base, said channel extending between the leading end of said slider and said inner recess for controlling sub-ambient pressure generated at the air bearing surface. ### Claim 22 (depends on 21) An air bearing slider as in claim 21, wherein said channel and said recesses are formed in a single etch step. ### Claim 23 (depends on 1) An air bearing slider as in claim 1, including a channel near the trailing end for connecting said recesses.