Abstract: Disclosed is a sheet-shaped air absorbent for a speaker-box system using porous carbon fibers and a speaker-box system including the same, wherein an air absorbent for a speaker-box system includes at least one sheet member, and the sheet member was made by weaving fibers comprising a porous carbon-based substance or a sheet member with at least two layers, and the sheet member was made by weaving fibers comprising a porous carbon-based substance.

Abstract: Disclosed is a sheet-shaped air absorbent for a speaker-box system using porous carbon fibers and a speaker-box system including the same, wherein an air absorbent for a speaker-box system includes at least one sheet member, and the sheet member was made by weaving fibers comprising a porous carbon-based substance or a sheet member with at least two layers, and the sheet member was made by weaving fibers comprising a porous carbon-based substance.

Abstract: A motor including: a rotor case having a chucking device, on which a disk is mounted, press-fitted and coupled thereto; disk support members mounted on an upper surface of the rotor case to support a bottom surface of the disk, and having each of flow path portions therebetween allowing for airflow in a space between the disk and the rotor case; and a push portion disposed in at least one of the rotor case and the disk support members to accelerate the airflow through the flow path portions when the rotor case rotates.

Abstract: There is provided a vibrator, including: a case having an inner space; a coil fixedly mounted on a side wall of the case; an elastic member fixedly mounted on the case so as to be disposed within the coil; a weight body fixedly mounted on the elastic member; and a magnet fixedly mounted on the weight body so as to face the coil.

Abstract: There are provided a motor capable of preventing scratches from occurring on an outer surface of a rotor case thereof, a method for manufacturing the same, and an optical disk drive using the same. The motor includes a shaft rotatably inserted into a bearing assembly; and a rotor case fixedly fastened to the shaft and rotating together with the shaft, wherein the rotor case is provided with a chamfered part along the outer peripheral edge of the bottom surface thereof. The rotor case includes a rotor hub fastened to an end of the shaft; an extending part extending in an outer-diameter direction from the rotor hub; and a vertical extending part formed to be vertically extended downwardly in a shaft direction from an outer peripheral edge of the extending part and having the chamfered part formed on the bottom end surface thereof.

Abstract: A motor including: a rotor case having a chucking device, on which a disk is mounted, press-fitted and coupled thereto; disk support members mounted on an upper surface of the rotor case to support a bottom surface of the disk, and having each of flow path portions therebetween allowing for airflow in a space between the disk and the rotor case; and a push portion disposed in at least one of the rotor case and the disk support members to accelerate the airflow through the flow path portions when the rotor case rotates.

Abstract: There is provided a turntable for a motor, including: a rotor case equipped with a chucking mechanism mounting a disk; a disk holding base part formed on the rotor case to be protruded by denting and disposed to be spaced apart from each other in order to form an air passage communicating a space formed between the disk and the top surface of the rotor case with the outer side of the rotor case; and a disk holding friction part stacked on the disk holding base part and grounded to the bottom surface of the disk.

Abstract: There is provided a stator core including a core back having an opening such that the core back is fixed to a stationary member by being pressed and fitted thereto; and a plurality of teeth portions being protruded from the core back in a radial direction, each teeth portion including a winding recess around which a coil is wound, wherein the core back and the teeth portions are formed by a sintering process. Since the coil is wound around the winding recess, the height of the wound coil can be reduced.

Abstract: There is provided a vibrator, including: a case having an inner space; a coil fixedly mounted on a side wall of the case; an elastic member fixedly mounted on the case so as to be disposed within the coil; a weight body fixedly mounted on the elastic member; and a magnet fixedly mounted on the weight body so as to face the coil.

Abstract: There is provided a vibrator, including: a case having an inner space; a vibration generating part mounted in the case and generating vibrations by power supplied thereto; and a resonance part resonated by the vibrations generated in the vibration generating part.

Abstract: Disclosed herein is a sensorless-type brushless DC motor, including: a magnet provided in a rotor; and a stator formed by winding a coil on a core stacked with sheets while facing the magnet, wherein the position of the rotor is detected by detecting back electromotive force induced to the coil, the back electromotive force includes a harmonic component 5 times higher than a fundamental wave, and an amplitude ratio of the 5-times harmonic wave to the fundamental wave is set to be 1% or more. Further, the sensorless-type brushless DC motor can prevent a failure in detecting an initial position of the rotor by controlling a waveform of the back electromotive force and minimize an increase of a starting time.

Abstract: There is provided a motor including: a rotor case having a chucking device, on which a disk is mounted, press-fitted and coupled thereto; and disk support members mounted on an upper surface of the rotor case to support a bottom surface of the disk, and having each of flow path portions therebetween allowing for airflow in a space between the disk and the rotor case, wherein a push portion is disposed in at least one of the rotor case and the disk support members to accelerate the airflow through the flow path portions when the rotor case rotates.

Abstract: There is provided a motor. The motor may include a rotor case including a driving magnet formed on an inner circumferential surface thereof and providing a driving force by interacting with a coil of a stator, a low-speed control magnet formed on an outer circumferential surface of the rotor case and generating a frequency allowing for low-speed rotation enabling label printing as the rotor case rotates at a low speed; and a sensing part sensing an analog signal generated from the low-speed control magnet.

Abstract: There are provided a motor capable of preventing scratches from occurring on an outer surface of a rotor case thereof, a method for manufacturing the same, and an optical disk drive using the same. The motor includes a shaft rotatably inserted into a bearing assembly; and a rotor case fixedly fastened to the shaft and rotating together with the shaft, wherein the rotor case is provided with a chamfered part along the outer peripheral edge of the bottom surface thereof. The rotor case includes a rotor hub fastened to anone end of the shaft; an extending part extending in an outer-diameter direction from the rotor hub; and a vertical extending part formed to be vertically extended downwardly in a shaft direction from anthe outer peripheral edge of the extending part and having the chamfered part formed on the bottom end surface thereof.

Abstract: There is provided a motor including: a rotor case having a chucking device, on which a disk is mounted, press-fitted and coupled thereto; and disk support members mounted on an upper surface of the rotor case to support a bottom surface of the disk, and having each of flow path portions therebetween allowing for airflow in a space between the disk and the rotor case, wherein a push portion is disposed in at least one of the rotor case and the disk support members to accelerate the airflow through the flow path portions when the rotor case rotates.

Abstract: There is provided a turntable for a motor, including: a rotor case equipped with a chucking mechanism mounting a disk; a disk holding base part formed on the rotor case to be protruded by denting and disposed to be spaced apart from each other in order to form an air passage communicating a space formed between the disk and the top surface of the rotor case with the outer side of the rotor case; and a disk holding friction part stacked on the disk holding base part and grounded to the bottom surface of the disk.

Abstract: There is provided a stator core including a core back having an opening such that the core back is fixed to a stationary member by being pressed and fitted thereto; and a plurality of teeth portions being protruded from the core back in a radial direction, each teeth portion including a winding recess around which a coil is wound, wherein the core back and the teeth portions are formed by a sintering process. Since the coil is wound around the winding recess, the height of the wound coil can be reduced.

Abstract: Disclosed herein is a sensorless-type brushless DC motor, including: a magnet provided in a rotor; and a stator formed by winding a coil on a core stacked with sheets while facing the magnet, wherein the position of the rotor is detected by detecting back electromotive force induced to the coil, the back electromotive force includes a harmonic component 5 times higher than a fundamental wave, and an amplitude ratio of the 5-times harmonic wave to the fundamental wave is set to be 1% or more. Further, the sensorless-type brushless DC motor can prevent a failure in detecting an initial position of the rotor by controlling a waveform of the back electromotive force and minimize an increase of a starting time.

Abstract: There is provided a motor. The motor may include a rotor case including a driving magnet formed on an inner circumferential surface thereof and providing a driving force by interacting with a coil of a stator, a low-speed control magnet formed on an outer circumferential surface of the rotor case and generating a frequency allowing for low-speed rotation enabling label printing as the rotor case rotates at a low speed; and a sensing part sensing an analog signal generated from the low-speed control magnet.

Abstract: A vibration actuator excites a mass member by interaction between an electric field of a vibration coil provided in an inner space of a case and a magnetic field of a magnetic field unit disposed corresponding to the vibration coil. The vibration actuator has an elastic wire having a wire body fixed to the outer surface of the mass member and elastic ends fixed to the inner surface of the case. The elastic wire is connected between the case and the mass member for elastically supporting mass member.