Abstract: In an optical disk drive device, in order to reduce structural vibration noise and aerodynamic sound during high-speed revolution, a recess is formed at the deeper end. This recess is in a position axially symmetric to a hole for the movement of an optical head with respect to the axis of a spindle motor, and its size is substantially equal to that of the movement hole. This recess serves to suppress the vibration mode of a disk tray and the air flow between the disk and the disk tray. Noise is reduced even when the disk is turning at high speed.

Abstract: Increases in the data transfer rates of optical disc drives have resulted in problems such as increases in optical disc vibrations due to higher rotation speeds or increases in heat generation due to increases in the output of motors for rotating the optical discs and in the output of laser diodes. To solve such problems, an optical pickup is provided with an air duct therein, and a space that is formed between the optical disc and a top case of a casing and that has negative pressure during rotation of the optical disc is connected to the air duct in the optical pickup via a tube, at least part of the tube being deformable. The optical pickup is cooled by the air flow through the air duct induced by pressure difference.

Abstract: The present invention provides a thin optical disc drive whose impact resistance performance is improved. An under cover 19 is provided with a collision evasion hole 21 at a position corresponding to an end of an optical head housing 25. Moreover, a bottom cover 4 is provided with an impact force buffering member 22 at a position corresponding to the collision evasion hole. When an impact force acts on an optical disc drive 1, the impact force to the optical head housing 25 is buffered by the structure. Consequently, it is possible to prevent the optical head 8 from being damaged, and it is possible to improve the reliability of the optical disc drive 1.

Abstract: An optical disc apparatus includes a main guide shaft and a subsidiary guide shaft disposed so as to guide movement of a sliding base which holds an optical pickup. The optical pickup enables information recording and reproducing operations on an optical disc. The main guide shaft and the subsidiary guide shaft are configured so as to suppress vibrational resonance caused between the main guide shaft and the subsidiary guide shaft.

Abstract: An optical disc apparatus has the following arrangements. Specifically, the optical disc apparatus includes a lock pin and a lock arm. The lock pin is disposed on a side of an inner surface of a case of the apparatus, being tapered in a protruding direction thereof. The lock arm is disposed on a side of a tray of the apparatus. The lock arm, urged by a resilient member, includes a hook portion to be engaged with an inclined surface of the lock pin. When the tray has moved to a predetermined position within the case, the lock arm is engaged with the lock pin, so that the tray is held in position at the predetermined position. When an impact force equal to, or more than, a predetermined value is applied to the optical disc apparatus, the hook portion of the lock arm is displaced in the protruding direction of the lock pin along the inclined surface of the lock pin, thereby disengaged from the lock pin. Engagement of the tray is thereby released.

Abstract: In an optical disk apparatus for recording and/or reading information with respect to an optical disk, comprising, a chassis for containing the optical disk, and a tray being movable with respect to the chassis and adapted to support the optical disk thereon so that the optical disk is movable with respect to the chassis, the chassis has an opening for discharging an air from an inside of the chassis to an outside of the chassis through the opening.

Abstract: A cathode electroactive material for use in lithium ion secondary cells, process for producing the material, and lithium ion secondary cells using the cathode electroactive material, wherein the electroactive material predominantly comprises an Li—Mn composite oxide particles with the spinel structure and particles of the electroactive material have an average porosity of 15% or less, the porosity being calculated by employing the following equation: Porosity (%)=(A/B)×100 (wherein A represents a total cross-section area of pores included in a cross-section of one secondary particle, and B represents the cross-section area of one secondary particle), a tapping density of 1.9 g/ml or more, a size of crystallites of 400 ?–960 ?, a lattice constant of 8.240 ? or less.

Abstract: A disk drive device has a configuration in which one of stepped parts defined by a circular recess for guiding a disc, formed in a disc tray is substantially flush with the bottom surface of the circular recess even in an area beyond the outer peripheral part of a disc so that no air cavity part facing the outer peripheral side surface of the disc is induced around the disc. Thereby, it is possible to aim at lowering cavity noise caused by the air cavity during high speed rotation and fluid noise caused by turbulence.

Abstract: In an optical disk drive device, in order to reduce structural vibration noise and aerodynamic sound during high-speed revolution, a recess is formed at the deeper end. This recess is in a position axially symmetric to a hole for the movement of an optical head with respect to the axis of a spindle motor, and its size is substantially equal to that of the movement hole. This recess serves to suppress the vibration mode of a disk tray and the air flow between the disk and the disk tray. Noise is reduced even when the disk is turning at high speed.

Abstract: An optical fiber measuring module is provided with an optical fiber cable (2) including an optical fiber core (2a), a cladding (2b) and a covering layer (2c), a base member (3) for holding the optical fiber cable (2), and an attachment member (4) for attaching the base member (3) to a structure (1).

Abstract: In a recording disk drive apparatus including, a chassis including a chassis body, a spindle motor fixed to the chassis body to support and rotationally drive a recording disk, and a head supported on the chassis body to be movable on the chassis body in a radial direction of the recording disk so that an information is recorded into the recording disk and/or read from the recording disk through the head, a base member on which the chassis is supported, and an elastic member through which the chassis is supported on the base member so that a vibration transmitted from the chassis is absorbed at least partially by an elasticity of the elastic member, the chassis includes a counter member elastically supported on the chassis body with a spring constant for the counter member in which spring constant the counter member is elastically movable with respect to the chassis body.

Abstract: A disc drive unit capable of preventing occurrence of errors in a recording system such as a CD or a DVD, using an optical head for recording data on a disc or reproducing data recorded on the disc. A disc tray is adapted to accommodate the disc, and load and unload the disc. A top cover is arranged above the disc. The top cover is formed therein with a concave and convex part for avoiding positioning a node of each of vibration modes (0, n) (where n=2, 3, 4) caused by a critical rotating speed of the disc, at a position right above the optical head.

Abstract: A cathode electroactive material for use in lithium ion secondary cells, process for producing the material, and lithium ion secondary cells using the cathode electroactive material, wherein the electroactive material predominantly comprises an Li—Mn composite oxide particles with the spinel structure and particles of the electroactive material have an average porosity of 15% or less, the porosity being calculated by employing the following equation: Porosity (%)=(A/B)×100 (wherein A represents a total cross-section area of pores included in a cross-section of one secondary particle, and B represents the cross-section area of one secondary particle), a tapping density of 1.9 g/ml or more, a size of crystallites of 400 ?-960 ?, a lattice constant of 8.240 ? or less.

Abstract: In a recording disk apparatus, a pickup element and an electric element for at lease one of supplying an electric power to at least one of a recording disk driving motor and the pickup and processing a signal to be recorded into the recording disk and/or the signal read from the recording disk are prevented from overlapping each other as seen in a thickness direction of the recording disk to restrain a thermal conduction between the pickup element and the electric element so that a thermal conduction restraining area extending along an imaginary directional line crossing an imaginary straight line passing the pickup element and the electric element as seen in the thickness direction is formed between the pickup element and the electric element as seen in the thickness direction.

Abstract: A cathode electroactive material for use in lithium ion secondary cells, process for producing the material, and lithium ion secondary cells using the cathode electroactive material, wherein the electroactive material predominantly comprises an Li—Mn composite oxide particles with the spinel structure and particles of the electroactive material have an average porosity of 15% or less, the porosity being calculated by employing the following equation: Porosity (%)=(A/B)×100 (wherein A represents a total cross-section area of pores included in a cross-section of one secondary particle, and B represents the cross-section area of one secondary particle), a tapping density of 1.9 g/ml or more, a size of crystallites of 400 ?-960 ?, a lattice constant of 8.240 ? or less.

Abstract: A paper feeder is capable of minimizing abnormal noise produced at a separation pad during paper feed, without reducing the paper feed capability, for use in an image forming apparatus using the same. Buffers are mounted on the separation pad. This arrangement ensures that, when a stick-slip condition occurs between the paper and separation pad during paper feed, and the separation pad is vibrated by the paper, the buffer vibrates so as to dissipate the vibration energy of the separation pad, with the result that the vibration of the separation pad is minimized, thereby to reduce any abnormal noise.

Abstract: In a disc driving apparatus, wherein a laser diode and a laser driver circuit board are mounted on a pickup housing in thermal contact therewith and are disposed adjacent to each other, a heat separation member is provided between the laser diode and the laser driver circuit board for effecting thermal separation therebetween, thereby reducing the thermal interference between the heat-generating elements that are adjacent to each other in the optical pickup. This makes it possible to protect the heat-generating elements from being deteriorated, leading to a reduction in the lifetime thereof, as well as, to improve the reliability thereof.

Abstract: A cathode electroactive material for use in lithium ion secondary cells, process for producing the material, and lithium ion secondary cells using the cathode electroactive material, wherein the electroactive material predominantly comprises an Li—Mn composite oxide particles with the spinel structure and particles of the electroactive material have an average porosity of 15% or less, the porosity being calculated by employing the following equation:

Abstract: A cathode electroactive material for use in lithium ion secondary cells, process for producing the material, and lithium ion secondary cells using the cathode electroactive material, wherein the electroactive material predominantly comprises an Li—Mn composite oxide particles with the spinel structure and particles of the electroactive material have an average porosity of 15% or less, the porosity being calculated by employing the following equation: Porosity (%)=(A/B)×100  (1) (wherein A represents a total cross-section area of pores included in a cross-section of one secondary particle, and B represents the cross-section area of one secondary particle), a tapping density of 1.9 g/ml or more, a size of crystallites of 400 Å-960 Å, a lattice constant of 8.240 Å or less.

Abstract: In the case when a disk is transported into or out of an apparatus, local contact noise is generated in a drive transmission gear and a clutch portion of a disk loading mechanism. Also, this phenomenon gives rise to problems relating to damage of parts, life of a loading motor and the like. Thus, a disk loading mechanism is provided to perform two operations of driving a disk tray in a disk transportation direction by means of a loading motor provided with a worm gear, via a first wheel gear and a second wheel gear, and also vertically raising and lowering a unit mechanism via a slide plate. In addition, a unit for controlling whirling of the above worm gear is provided to reduce contact noise of the gear and clutch portion and improve the reliability of a disk drive apparatus.