Abstract: A carbon nanotube synthesis process apparatus comprises a reaction tube in which a reaction field is formed, and a discharge pipe (32) arranged downstream of the reaction tube and discharging carbon nanotubes to the outside. A plurality of nozzles (34) are provided on the sidewall of the discharge pipe (32) in directions which are deflected with respect to the center (O) of the discharge pipe (32). When gases are discharged from the plurality of nozzles (34), a swirl flowing from the inner side surface along the inner side surface is produced in the discharge pipe (32). Adhesion of carbon nanotubes to the inner side surface of the discharge pipe (32) is prevented by the swirl flow and thus the apparatus can be operated continuously.

Abstract: A production amount and a yield in a carbon nanotube producing device are improved. Inside a reaction pipe (20) heated so as to become a circumference heating body, a plurality of nozzles (26) for injecting a material and carrier gas into the reactor pipe and at least one internal heating source (24) are arranged. By arranging a plurality of the nozzles, the production amount is increased. The nozzles are arranged so as to be sandwiched by two heating sources (circumference heating element, internal heating source) and a distance to the closest two heating source peripheral walls is “a”. Also, a distance between the adjacent nozzles is “b” (?2a). Flows of the material and the carrier gas injected by the nozzles do not interfere with each other or the heating source wall, and the yield is increased.

Abstract: A method for writing data to a disk drive. The method includes: receiving a write command; and, determining whether a beginning and an end of a rewrite area specified by the write command agree with boundaries of large-sized data sectors on a disk. The method also includes: reading head and tail data sectors and making a backup of the head and tail data sectors in first and second non-volatile memory areas, respectively, if the beginning of the rewrite area does not agree with the boundaries. The method includes starting a rewrite of the rewrite area after completing backups into first and second non-volatile memory areas. Moreover, the method includes: determining a state stage by using data in first, second, third and fourth non-volatile memory areas if a power shut-down occurs during execution of the write command; and, executing a recovery process in accordance with the determined state stage.

Abstract: A method for writing data to a disk drive. The method includes: receiving a write command; and, determining whether a beginning and an end of a rewrite area specified by the write command agree with boundaries of large-sized data sectors on a disk. The method also includes: reading head and tail data sectors and making a backup of the head and tail data sectors in first and second non-volatile memory areas, respectively, if the beginning of the rewrite area does not agree with the boundaries. The method includes starting a rewrite of the rewrite area after completing backups into first and second non-volatile memory areas. Moreover, the method includes: determining a state stage by using data in first, second, third and fourth non-volatile memory areas if a power shut-down occurs during execution of the write command; and, executing a recovery process in accordance with the determined state stage.

Abstract: A carbon nanotube synthesis process apparatus comprises a reaction tube in which a reaction field is formed, and a discharge pipe (32) arranged downstream of the reaction tube and discharging carbon nanotubes to the outside. A plurality of nozzles (34) are provided on the sidewall of the discharge pipe (32) in directions which are deflected with respect to the center (O) of the discharge pipe (32). When gases are discharged from the plurality of nozzles (34), a swirl flowing from the inner side surface along the inner side surface is produced in the discharge pipe (32).

Abstract: A production amount and a yield in a carbon nanotube producing device are improved. Inside a reaction pipe (20) heated so as to become a circumference heating body, a plurality of nozzles (26) for injecting a material and carrier gas into the reactor pipe and at least one internal heating source (24) are arranged. By arranging a plurality of the nozzles, the production amount is increased. The nozzles are arranged so as to be sandwiched by two heating sources circumference heating element, internal heating source) and a distance to the the closest two heating source peripheral walls is “a”. Also, a distance between the adjacent nozzles is “b” (?2a). Flows of the material and the carrier gas injected by the nozzles do not interfere with each other or the heating source wall, and the yield is increased.

Abstract: A method (and structure) senses a rotational vibration of a disk drive. The disk drive includes a rotating disk. The disk includes a plurality of reference bits across a surface thereof. The method (and structure) includes detecting the reference bits across a pattern on the rotating disk, and analyzing a time interval between adjacent ones of the reference bits.

Abstract: To improve the probability of error correction, thereby generating correct read data. Data is read from the same sector by a number of times and a majority decision is done in the same address, thereby the most frequently read value is regarded as the true data value in the address. For example, for an address 00, “00” is handled as a true data value.

Abstract: A method (and structure) senses a rotational vibration of a disk drive. The disk drive includes a rotating disk. The disk includes a plurality of reference bits across a surface thereof. The method (and structure) includes detecting the reference bits across a pattern on the rotating disk, and analyzing a time interval between adjacent ones of the reference bits.

Abstract: A method (and structure) senses a rotational vibration of a disk drive. The disk drive includes a rotating disk. The disk includes a plurality of reference bits across a surface thereof. The method (and structure) includes detecting the reference bits across a pattern on the rotating disk, and analyzing a time interval between adjacent ones of the reference bits.

Abstract: The hard disk drive comprises: a magnetic disk 2 having servo information stored; magnetic heads 4 seeking on the magnetic disk 2 and staying at a predetermined position to read or write data; a voice coil motor 6 moving the magnetic heads 4 to the predetermined position of the magnetic disk 2; a position controller supplying a driving current to the voice coil motor 6 based on the servo information read by the magnetic heads 4. The position controller includes: a CPU 12 outputting a speed control value based on the servo information; a DAC 7 and a VCM driver 8 converting the speed control value into the driving current; and a controller 10 limiting a driving speed of the voice coil motor 6 in a case that an output timing of the speed control value is shifted.

Abstract: A disk drive, a servo controller, and a controller which have realized high-degree control by lightening processing load to a microprocessor unit (MPU) without increasing cost is disclosed. An analog/digital (AD) converter (ADC) performs the AD conversions of the regenerated levels A, B, C, and D of burst patterns supplied from a channel and retains the converted levels in an ADC register. A servo assist (SA) computes parameters, such as the position error of a head, independently of an MPU, based on the regenerated levels of the burst patterns retained in the ADC register and an instruction from the MPU retained in a SRAM. Based on the computed parameters, the SA computes servo data (DACOUT) for driving a voice coil motor and supplies the servo data to the DAC section of a VCM driver section through a SIO.

Abstract: A method (and structure) senses a rotational vibration of a disk drive. The disk drive includes a rotating disk. The disk includes a plurality of reference bits across a surface thereof. The method (and structure) includes detecting the reference bits across a pattern on the rotating disk, and analyzing a time interval between adjacent ones of the reference bits.

Abstract: A method and apparatus to provide a retract circuit that can correspond to the tendency toward miniaturization and low supply voltage. When drive supply voltage Vcc is applied, a retract circuit charges a retract condenser Cr with boosted voltage Vup, equal to three times Vcc, generated by a booster circuit. Then, if the drive supply voltage Vcc is cut off and a VCM driver stops, the retract circuit detects power-off with a power OFF sense circuit, and provides retract delay time by a retract delay circuit. Furthermore, when the retract delay time elapses after the drive power supply is turned off, the retract driver switches the switching circuits on, discharges the retract condenser, charged at the boosted voltage, supplies discharge current to a voice coil, and retracts the head assembly.

Abstract: To improve the probability of error correction, thereby generating correct read data. Data is read from the same sector by a number of times and a majority decision is done in the same address, thereby the most frequently read value is regarded as the true data value in the address. For example, for an address 00, “00” is handled as a true data value.

Abstract: Methods and systems for detecting and correcting for undesirable vibrations impacting the servo systems in data storage devices. A detection technique is provided wherein a detection filter is configured to scan a position signal of the servo system across a range of frequencies, and, at each respective scanned frequency, record an amplitude associated therewith. The recorded amplitudes are examined to determine whether any exceed a threshold, thereby locating a peak frequency of the vibration. Using the detected peak frequency of the vibration, a corrective filter is configured to operate about the peak frequency of vibration, thereby reducing its impact on the position signal in the servo system.

Abstract: The hard disk drive comprises: a magnetic disk 2 having servo information stored; magnetic heads 4 seeking on the magnetic disk 2 and staying at a predetermined position to read or write data; a voice coil motor 6 moving the magnetic heads 4 to the predetermined position of the magnetic disk 2; a position controller supplying a driving current to the voice coil motor 6 based on the servo information read by the magnetic heads 4. The position controller includes: a CPU 12 outputting a speed control value based on the servo information; a DAC 7 and a VCM driver 8 converting the speed control value into the driving current; and a controller 10 limiting a driving speed of the voice coil motor 6 in a case that an output timing of the speed control value is shifted.

Abstract: A disk drive, a servo controller, and a controller which have realized high-degree control by lightening processing load to a microprocessor unit (MPU) without increasing cost is disclosed. An analog/digital (AD) converter (ADC) performs the AD conversions of the regenerated levels A, B, C, and D of burst patterns supplied from a channel and retains the converted levels in an ADC register. A servo assist (SA) computes parameters, such as the position error of a head, independently of an MPU, based on the regenerated levels of the burst patterns retained in the ADC register and an instruction from the MPU retained in a SRAM. Based on the computed parameters, the SA computes servo data (DACOUT) for driving a voice coil motor and supplies the servo data to the DAC section of a VCM driver section through a SIO.

Abstract: A hard disk drive (HDD) having a control unit that reduces the number of control signals required to control the operation of the channel and amplifier. The HDD includes a control unit for controlling reading or writing data from or to a magnetic head, a preamplifier for amplifying the data from the magnetic head, and a channel module which is controlled by the control unit. The channel module converts digital data signals to data write signals and also converts analog signals from the preamplifier to digital signals. Control information is transmitted to the channel module over the data bus which is used to transmit or receive data read/write signals. The channel module performs control in response to transmitted control information.

Abstract: Methods and systems for detecting and correcting for undesirable vibrations impacting the servo systems in data storage devices. A detection technique is provided wherein a detection filter is configured to scan a position signal of the servo system across a range of frequencies, and, at each respective scanned frequency, record an amplitude associated therewith. The recorded amplitudes are examined to determine whether any exceed a threshold, thereby locating a peak frequency of the vibration. Using the detected peak frequency of the vibration, a corrective filter is configured to operate about the peak frequency of vibration, thereby reducing its impact on the position signal in the servo system.