摘要:
When a rotary-actuator voice coil type disk drive is powered down the actuator arm is moved to a parking position against an I.D. stop by a disk spindle motor back EMF, resulting from the spinning down of the spindle motor. Current is applied by the back EMF through a delay circuit to a latch arm voice coil on one end of a latch arm and forming part of a magnetic circuit including a drive permanent magnet on a ferrous base plate and a ferrous upper plate. Resultant movement of the latch arm overcomes a spring bias of a torsion spring extending between the base plate and pivoted latch arm normally keeping the latch arm in an unlatched position. A latch permanent magnet extends from the other end of the latch arm and is brought into spaced proximity, but not contact, with a ferrous member extending from the actuator arm so that the magnetic force therebetween holds the actuator arm against the I.D. stop in latched position to withstand high shock loadings. Powering the rotary actuator voice coil motor up overcomes the magnetic force and allows the biased torsion spring to move the latch arm to the unlatched position without resultant loss of data storage area.
摘要:
A hard disk drive for a computer system including a head disk assembly with a disk platter of approximately one-and-eight-tenths-inch in diameter capable of storing more than forty megabytes. In an embodiment, data tracks on each data surface of the platter are spaced at approximately 2,558 tracks per inch and each data track has approximately 36,000 flux changes per inch. An actuator positions a pair of read/write heads on each platter surface using a voice coil motor to position the heads over a cylinder. A magnetic actuator latch attaches to another magnet on the actuator and locks the heads in a parked position at the innermost diameter of the platter. A spindle motor rotates the platter at approximately 5,400 revolutions per minute. A base plate, with a gasketed surface and a raised lip, hermetically seals with a cover to the base plate such that the platter, the actuator, the actuator latch, and the spindle motor are all contained within. The cover carries a breather filter and recirculating air filter. The raised lip on the base plate prevents direct electrical interference from passing between the base plate and the cover.
摘要:
A magnetic head suspension assembly is fabricated with an integral piece which includes a load beam section, a flexure section, a rear mount section and a leaf spring section between the load beam and rear mount. A tongue extends from the load beam to the flexure and has a down-facing load dimple which contacts the non-air bearing surface of an attached air bearing slider. The flexure includes narrow thin legs adjacent to a cutout that delineates the load beam tongue. The head suspension is characterized by a high first bending mode frequency and low pitch and roll stiffness.
摘要:
The invention provides for improved devices and methods for forming openings in a biological membrane for delivering substances into an animal through the biological membrane for treatment applications, or extracting substances from the animal through the biological membrane for monitoring or other diagnosis applications and for increased transmembrane flux.
摘要:
A method of enhancing the permeability of the skin to an analyte for diagnostic purposes or to a drug for therapeutic purposes is described utilizing microporation and optionally sonic energy and a chemical enhancer. If selected, the sonic energy may be modulated by means of frequency modulation, amplitude modulation, phase modulation, and/or combinations thereof. Microporation is accomplished by (a) ablating the stratum corneum by localized rapid heating of water such that such water is vaporized, thus eroding the cells; (b) puncturing the stratum corneum with a micro-lancet calibrated to form a micropore of up to about 1000 .mu.m in diameter; (c) ablating the stratum corneum by focusing a tightly focused beam of sonic energy onto the stratum corneum; (d) hydraulically puncturing the stratum corneum with a high pressure jet of fluid to form a micropore of up to about 1000 .mu.m in diameter, or (e) puncturing the stratum corneum with short pulses of electricity to form a micropore of up to about 1000 .mu.m in diameter. A dye with an absorption maximum matched to the wavelength of a pulsed light source can be absorbed into the stratum corneum to concentrate the energy of the pulsed light source and aid in ablation of the stratum corneum. Alternatively, a hot wire can be caused to contact the stratum corneum.
摘要:
A system and method for detecting a measuring an analyte in a biological fluid of an animal. A harvesting device (10) is provided suitable for positioning on the surface of tissue of an animal to harvest biological fluid therefrom. The harvesting device (10) comprises an analyte sensor (50) positioned to be contacted by the harvested biological fluid and which generates a measurement signal representative of the analyte. At least one attribute sensor (40) is provided to measure an attribute associated with the biological fluid harvesting operation of the harvesting device (10) or the assay of the biological fluid, and which generates an attribute signal representative of the attribute. Adjustments are made to operational parameters of the harvesting device (10) based on the one or more attributes.
摘要:
A method of enhancing the permeability of the skin to an analyte for diagnostic purposes or to a drug for therapeutic purposes is described utilizing microporation and optionally sonic energy and a chemical enhancer. If selected, the sonic energy may be modulated by means of frequency modulation, amplitude modulation, phase modulation, and/or combinations thereof. Microporation is accomplished by (a) ablating the stratum corneum by localized rapid heating of water such that such water is vaporized, thus eroding the cells; (b) puncturing the stratum corneum with a micro-lancet calibrated to form a micropore of up to about 1000 .mu.m in diameter; (c) ablating the stratum corneum by focusing a tightly focused beam of sonic energy onto the stratum corneum; (d) hydraulically puncturing the stratum corneum with a high pressure jet of fluid to form a micropore of up to about 1000 .mu.m in diameter, or (e) puncturing the stratum corneum with short pulses of electricity to form a micropore of up to about 1000 .mu.m in diameter. A dye with an absorption maximum matched to the wavelength of a pulsed light source can be absorbed into the stratum corneum to concentrate the energy of the pulsed light source and aid in ablation of the stratum corneum. Alternatively, a hot wire can be caused to contact the stratum corneum.
摘要:
An optimized bump and offset along the spring section of a load beam of a head-gimbal assembly ("HGA") in the loaded state redistributes the mass and stiffness distributions of the load beam from a truly flat state, so that the mode shape of the first torsional resonance mode is changed such that the coupling between a drive actuator head arm and the head slider is essentially eliminated. A fabrication method to produce the desired bump and offset, and a characterization method to ascertain that optimized bump and offset parameters have been achieved are also disclosed. By optimizing bump and offset, the slider remains independent from any load beam first torsional vibration even at resonance and/or sway mode resonant frequency of the HGA may be increased.
摘要:
A self-contained hydrodynamic bearing unit includes a shaft and a shaft housing defining an opening for receiving the shaft for relative rotation. The shaft and bearing define at least one radial hydrodynamic bearing and an annular thrust bearing, formed as a disk portion extending radially outward of a main cylindrical surface of the shaft which cooperates with an adjacent annular face of the shaft housing. A gap between an outer cylindrical wall of the thrust bearing disk portion and an adjacently facing cylindrical surface of the shaft housing provides a primary annular capillary seal segment. An annular bushing ring extends from the housing radially inwardly to enclose the thrust bearing disk, and cooperates with an adjacent outer face of the thrust bearing disk to provide a secondary containment capillary seal segment. Normally, lubricating liquid is in the bearing unit at the radial hydrodynamic bearing, at the hydrodynamic thrust bearing and in the primary annular capillary seal segment. However, if liquid overflows from, or extends beyond the primary seal segment as by thermal expansion, it is contained in the secondary seal segment and urged to return by centrifugal force to the primary seal segment. A tertiary containment seal may also be provided to prevent escape of liquid to the external ambient.