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Hiroshi Iwai

Hiroshi Iwai, Shizuoka JP

Patent application numberDescriptionPublished
20100202084DISK DRIVE DEVICE - In a brushless motor, the rotational frequency N (Hz) of the hub satisfies N08-12-2010
20100220412MANUFACTURING METHOD OF DISK DRIVE DEVICE CAPABLE OF REDUCING AMOUNT OF UNBALANCE, DISK DRIVE DEVICE AND SUBASSEMBLY THEREOF - A disk drive device is provided with a recording disk, a base member, a bearing unit, and a hub member. In a marking step, unbalance information indicating the displacement of the center of gravity of the hub member with respect to the rotation center of the hub member is acquired, and an information mark containing the unbalance information is applied to at least the hub member or the base member. In an installing and adjustment step, the unbalance information is read form the information mark, and the position for installing the recording disk in an outer cylinder part is determined in accordance with the unbalance information so as to install the recording disk on the hub member.09-02-2010
20100238590DISK DRIVE DEVICE ROTATIONALLY DRIVING RECORDING DISK - A disk drive device is provided with a base, a hub on which a recording disk is to be mounted, a bearing unit arranged on the base and configured to rotatably support the hub, and a spindle drive unit configured to rotatably drive the hub. A circumferential ring wall portion is arranged on the outer circumference of the base and formed of a plastic.09-23-2010
20110043948DISK DRIVE DEVICE WITH HUB - The disk drive device includes a base member, a hub, a bearing unit which is arranged on the base member and which rotatably supports the hub, and a spindle drive unit which drives the hub to rotate. The spindle drive unit includes a stator core having a salient pole, a coil wound around the salient pole and a magnet opposed to the salient pole. The hub formed of magnetic material includes an outer cylinder portion engaged with an inner circumference of a recording disk and an inner cylinder portion to which an outer circumference of the magnet is fixed. The diameter of the inner cylinder portion is larger than the diameter of the outer cylinder portion.02-24-2011
20110064341DISK DRIVE DEVICE CAPABLE OF BEING IMPROVED IN ANTI-VIBRATION CHARACTERISTIC - A disk drive device includes: a hub on which a recording disk is to be mounted; a shaft; a sleeve configured to house the shaft and to be rotatable relatively with respect to the shaft; a radial space portion formed between the inner circumferential surface of the sleeve and the outer circumferential surface of the shaft; a radial dynamic pressure generating portion configured to generate radial dynamic pressure between at least part of the inner circumferential surface of the sleeve and the outer circumferential surface of the shaft in the radial space portion; and lubricant. The axial length of the radial dynamic pressure generating portion is formed to be longer than the diameter of the radial dynamic pressure generating portion such that radial dynamic pressure, which is defined with the axial length of the radial dynamic pressure generating portion and the diameter thereof being parameters, is greater than or equal to a predetermined minimum reference value.03-17-2011
20110080673METHOD MANUFACTURING OF FLUID DYNAMIC BEARING USING CUTTING TOOL THAT PERFORMS MICRO ALTERNATING DRIVE, FLUID DYNAMIC BEARING MANUFACTURED BY USING THE METHOD, AND DISK DRIVE DEVICE USING THE BEARING - A method manufacturing of a fluid dynamic bearing includes: forming a substantially linear groove having a length corresponding to a circumferential direction width of the dynamic pressure groove formed on the inner circumferential surface of a shaft housing hole portion, along the circumferential direction of a surface orthogonal to a first processing direction along the central axis direction of a work, by a byte that performs a micro alternating drive in a second processing direction orthogonal to the first processing direction; and extending the dynamic pressure groove that extends in the first processing direction by continuously forming the substantially linear grooves in the first processing direction by displacing the relative positions of the work and the byte in the first processing direction.04-07-2011
20110096437DISK DRIVE DEVICE HAVING A LAMINATED CORE - In A disk drive device, a magnetic recording disk is to be mounted on a hub. A base plate rotatably supports the hub through a bearing unit. A projecting portion is formed on the upper surface of the base plate. The projecting portion has a cylindrical side surface, the center of which being along the rotational axis of the motor. A laminated core is formed by laminating eight magnetic steel sheets and has a ring portion and a plurality of teeth that extend radially from the ring portion. The disk drive device has a tubular vibration-deadening ring. The outer surface of the vibration-deadening ring is press-fitted into the ring portion, and the inner surface is fixed to the side surface of the projecting portion. The outer surface of the vibration-deadening ring is pressed against the ring portion at least at a position closer, in the direction along the rotational axis of the motor, to the upper surface of the laminated core than to the lower surface of the laminated core.04-28-2011
20110154875PRODUCTION METHOD OF ROTATING DEVICE HAVING THRUST DYNAMIC PRESSURE GENERATING SITE ON WHICH A THRUST PRESSURE PATTERN IS FORMED AND ROTATING DEVICE PRODUCED BY SAID PRODUCTION METHOD - A thrust dynamic pressure pattern is marked on a rotating member or fixed member set on a rest table. A pressure for marking is applied to a member to be marked in a cycle of applying and releasing the pressure, and a supplemental force for keeping the member to be marked, still is separately applied. According to the present embodiment, a rotating device can be provided that narrows down a bearing gap and improves the efficiency of raking up a lubricant so as to increase the dynamic pressure by reducing the deformation of the shape of the protrusions of a thrust dynamic pressure pattern and the variation in the height of the protrusions when forming the thrust dynamic pressure pattern in a method of producing a rotating device.06-30-2011

Hiroshi Iwai, Yokohama-Shi JP

Patent application numberDescriptionPublished
20090057739Ge channel device and method for fabricating ge channel device - The Ge channel device comprises: a Ge channel layer (03-05-2009